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PMC11697680 | Section title: Background Educational score: 4.088038921356201 Domain: biomedical Document type: Study Language: en COVID-19 has had a severe impact on global public health systems and remains one of the most severe epidemics now over the world. As of January 2023, WHO reported about 750 million confirmed cases of COVID-19 globally, covering about 6.8 million deaths . The virus is constantly mutating, and the number of infected people continues to grow rapidly. According to statistics from outpatient and emergency clinics in various hospitals, about 40–50% of the patients are prone to serious illnesses and thus require hospital admission. Of these, 10–20% of patients are prone to critical illnesses and need to be admitted to intensive care units (ICUs) for supportive treatment. Consequently, the number of COVID-19 patients admitted to ICUs has markedly increased, and in some places, temporary ICUs have even been built in large numbers. Previous studies have shown that bloodstream infection (BSI) may occur in approximately 7% of COVID-19 inpatients . The incidence of BSI in COVID-19 patients in ICUs is 10–50%, which is a significant increase and a new record and is four times higher than that in non-COVID-19 patients . BSI can lead to bacterial or viral infections in various organs. In poorly treated or severe cases, it may lead to sepsis, resulting in fever and generalized pain, which gravely impacts the health. In severe cases, it can lead to the risk of death. ICU-BSI increases the risk of 30-day mortality by 40% . In addition, resuscitation therapy such as mechanical ventilation and endotracheal intubation in ICU increases the risk of BSI and poses a great challenge to anti-infective treatment [ 5 – 7 ]. COVID-19 infection may become a small-scale recurrent epidemic pattern in the future. Thereby, it is necessary to stratify patients at risk of BSI and take timely measures to reduce the occurrence of BSI. Section title: Background Educational score: 4.073768615722656 Domain: biomedical Document type: Study Language: en Recent studies found that gender, SAPS II score, underlying medical complications [e.g., diabetes mellitus (DM), hypertension], treatment-related factors (e.g., mechanical ventilation, intubation, ECMO), and drug-related factors (e.g., Tocilizumab, Methylprednisolone) might be associated with an increased risk of BSI in critically ill patients with COVID-19 in ICUs. However, the conclusions of various studies about the risk factors for BSI are inconsistent. Regarding gender, most studies found that men had a higher risk of developing BSI, which reached 60–70%, and men accounted for most COVID-19 admissions to ICUs [ 8 – 13 ]. Some studies concluded that gender was not associated with the risk of infection [ 14 – 18 ]. Interestingly, 2 studies found the risk of BSI was equal for males and females . DM, as the most common underlying disease in human beings, is statistically associated with a higher risk of BSI in most studies [ 8 , 10 , 13 , 15 – 18 , 20 , 21 ]. However, other studies concluded that DM did not lead to a higher risk of BSI . Additionally, the conclusions regarding hypertension were not clear and consistent. In most studies, statistical analyses suggested that hypertension caused a higher risk of BSI [ 10 – 13 , 16 , 18 , 19 ]; whereas some studies indicated no direct correlation between hypertension and the risk of BSI . Therefore, in this study, we aimed to determine the risk factors for BSI in COVID-19 patients in ICUs through a systematic review and meta-analysis. Section title: Methods Educational score: 1.479781985282898 Domain: biomedical Document type: Other Language: en This paper was designed and revised following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and was registered in the PROSPERO . Section title: Search strategy Educational score: 3.9305717945098877 Domain: biomedical Document type: Study Language: en PubMed, Embase, Web of Science, and Cochrane Library were comprehensively searched for English papers up to July 2024, while references in related literature were manually checked. The following keywords were utilized to screen published clinical information on risk factors for BSI in COVID-19 patients in ICUs: “intensive care unit”, “covid-19”, “sepsis”, and “bloodstream infection”. All literature retrieved was imported into EndnoteX9 for paper screening. The search process was undertaken by two reviewers and any disagreements were addressed through discussion. (Table S1) Section title: Eligibility criteria Educational score: 3.340113401412964 Domain: biomedical Document type: Study Language: en Inclusion criteria covered: (1) study type: observational study; (2) patients: with COVID-19 in ICUs; (3) study content: risk factors for BSI in COVID-19 patients in ICUs. Exclusion criteria encompassed: (1) letters, reviews, conference proceedings, commentaries, and papers with unavailable full text and unsuitable types of publication; (2) with no available primary data; (3) published not in English. Section title: Data extraction Educational score: 4.075390815734863 Domain: biomedical Document type: Study Language: en Based on the eligibility criteria, articles imported into EndnoteX9 were initially screened by reviewing the titles and abstracts. Ineligible articles were excluded, and the remaining articles were read through the full text to screen the eligible ones for meta-analysis. Relevant research data were extracted. All procedures were performed by two researchers (Ting Jiang and Jun Wang). The following data were extracted: (1) general information: authors, publication date, study area, study design, and period; (2) study characteristics: sample size, mean age, and gender distribution; (3) risk factors: SAPS II, hypertension, DM, chronic pulmonary disease, liver disease, immunosuppression, chronic kidney disease, heart disease, and tumors; and (4) treatment records: medication administration, treatment modalities, and duration of treatment. In studies where some information was lacking, we attempted to contact the authors by phone or email. In case of disagreement in literature screening and data extraction, a third researcher (Wei Wang) was consulted. Section title: Quality assessment Educational score: 4.058492660522461 Domain: biomedical Document type: Study Language: en Two researchers independently assessed the study quality based on the Newcastle-Ottawa Scale (NOS) for cohort studies and case-control studies. The NOS scale covered three dimensions and eight items, with a maximum score of 9 points. A score < 4 was defined as low quality, 4–6 as moderate quality, and ≥ 7 as high quality. The higher score implied a lower risk of bias. The quality of cross-sectional studies was evaluated using a scale recommended by the Agency for Healthcare Research and Quality. The scale consisted of 11 items. Answers included yes, no, and unclear. For the answer of “yes”, the item was assigned a score of 1. The higher the score, the higher the quality: low quality = 0–3; medium quality = 4–7; high quality = 8–11. If two researchers disagreed with quality assessment, a third researcher arbitrated. Section title: Statistical analyses Educational score: 4.063343524932861 Domain: biomedical Document type: Study Language: en Statistical analyses were implemented using Stata 15.0 software. Categorical variables were analyzed using odds ratio (OR) while continuous variables using weighted mean difference (WMD). Data from the original studies were transformed before meta-analysis if they were not described as mean and standard deviation. All effect sizes were represented as 95% confidence intervals (CI). Heterogeneity was analyzed using I 2 . If there was no significant statistical heterogeneity between outcomes ( P ≥ 0.1, I 2 ≤ 50%), a meta-analysis was performed using a fixed-effects model, otherwise, using a random-effects model. For highly heterogeneous results, sensitivity analyses were performed on the results to validate the stability and reliability of the results. Sensitivity analyses were conducted on all outcomes. By eliminating the articles one by one, the stability of the remaining results was observed. For risk factors that included ≥ 10 articles, the Egger test was adopted to determine whether there was publication bias. Section title: Screening results Educational score: 3.8788394927978516 Domain: biomedical Document type: Study Language: en The database searches retrieved 9099 relevant English articles. 6914 articles were obtained after duplicates were removed. Subsequently, the titles and abstracts were read to exclude the ineligible studies, leaving 301 studies. Finally, after reading the full text, 55 studies were enrolled in the meta-analysis [ 3 , 5 – 58 ]. The screening process is represented in a PRISMA flowchart. . Section title: Screening results Educational score: 2.1903493404388428 Domain: biomedical Document type: Study Language: en Fig. 1 Flowchart of the search strategy Section title: Characteristics Educational score: 4.043088436126709 Domain: biomedical Document type: Study Language: en The 55 included studies comprised 48 cross-sectional studies [ 5 – 9 , 11 , 12 , 14 , 15 , 17 , 18 , 20 – 23 , 26 – 58 ] (Table 1 ), 6 cohort studies , and 1 case-control study (Table 2 ), including 25,939 patients ranging in age from 18 to 94 years across Italy, CHN, UK, US, Spain, France, Greece, Austria, Singapore, India, Germany, Turkey, Switzerland, Sweden, and Portugal. The meta-analysis results of the research indicators are shown in Table 3 . Among them, 48 cross-sectional studies had average AHRQ scale scores > 7, and 6 cohort studies and 1 case-control study had average NOS scores > 7, implying that these articles were all of high quality. Section title: Characteristics Educational score: 4.147133827209473 Domain: biomedical Document type: Study Language: en Table 1 Studies characteristics and quality. (cross-sectional study) Study Published time Country Study design Patients Age Gender(male) AHRQ grade Amit, M. et al. 2020 Israel Cross-sectional study 156 72(60–82) 108/48 9 Bonazzetti, C et al. 2020 Italy Cross-sectional study 89 61.5(53.1–68.7) 69/20 8 Fu, Guoping et al. 2020 CHN Cross-sectional study 51 60.94 ± 14.87(25–87) 27/14 8 Giacobbe, D. R et al. 2020 Italy Cross-sectional study 78 66 IQR 57–70 60/18 9 Anwar, Asad et al. 2021 UK Cross-sectional study 44 17–77 M59.5(IQR 50.5–64.5)/21–80 M59(IQR 49–67.5) 34/10 8 Bardi, Tommaso et al. 2021 Spain Cross-sectional study 140 61(57–67) 108/32 8 d’Humières, C et al. 2021 FRANCE Cross-sectional study 197 59(50–68) 148/49 8 Dupuis, Claire et al. 2021 FRANCE Cross-sectional study 303 61(53–70) 239/64 9 Grasselli, G. et al. 2021 Italy Cross-sectional study 774 62 (54–68) 597/177 9 Karruli, A. et al. 2021 Italy Cross-sectional study 32 68 [55.25–75] 23/9 9 Kokkoris, S. et al. 2021 Greece Cross-sectional study 50 Median age 64 36/14 8 Llitjos, Jean-Francois et al. 2021 FRANCE Cross-sectional study 176 63 (55–73) 134/42 8 Ong, C. C. H. et al. 2021 Singapore Cross-sectional study 71 52(39–66) 59/12 9 Ramos, Rafael et al. 2021 Spain Cross-sectional study 213 61(52–71) 110/103 8 Roedl, Kevin et al. 2021 Germany Cross-sectional study 223 69 (58–77.5) 163/60 8 Rollas, Kazim et al. 2021 Turkey Cross-sectional study 38 NR NR 9 Søgaard, K. K et al. 2021 Switzerland Cross-sectional study 41 64.8(54.7–72.1) 31/10 9 Suarez-de-la-Rica, A. et al. 2021 Spain Cross-sectional study 107 62.2 ± 10.6 76/31 8 Yakar, Mehmet Nuri et al. 2021 Turkey Cross-sectional study 249 71(61–80) 172/77 9 Yao, Ren-qi et al. 2021 CHN Cross-sectional study 35 64(59–67) 25/10 8 Zamora-Cintas, M. I. et al. 2021 Spain Cross-sectional study 54 NR NR 8 Zhang, J. et al. 2021 CHN Cross-sectional study 32 63.34 ± 12.48 20/12 9 Ahlstrom, Bjorn et al. 2022 Swedish Cross-sectional study 7382 63 (53–72) 5191/2191 9 Brücker, W. et al. 2022 Germany Cross-sectional study 61 66.4 ± 13.3 34/27 9 Caiazzo, L.et al. 2022 Italy Cross-sectional study 89 68.1 ± 9.3 66/23 8 Cidade, Jose Pedro et al. 2022 Portugal Cross-sectional study 118 63.3 ± 13.1 87/31 8 Ćurčić, M. et al. 2022 Croatia Cross-sectional study 692 NR NR 8 da Costa, R. L. et al. 2022 Brazil Cross-sectional study 191 69.66 ± 16.13 116/75 8 De Bruyn, A. et al. 2022 Belgium. Cross-sectional study 94 69.65 ± 11.29 55/39 9 DeVoe, C. et al. 2022 US Cross-sectional study 126 58.1 ± 17.9 85/41 8 Erbay, Kubra et al. 2022 Turkey Cross-sectional study 85 67.23 ± 13.05 54/31 8 Kozlowski, Bartosz et al. 2022 Poland Cross-sectional study 172 67.76 ± 11.16 112/60 8 Kurt, Ahmet Furkan et al. 2022 Turkey Cross-sectional study 470 66 ± 14.87 301/169 9 Lepape, Alain et al. 2022 FRANCE Cross-sectional study 4465 63.30 ± 11.68 3132/1333 8 Mantzarlis, K. et al. 2022 Greece Cross-sectional study 84 68.85 ± 12.17 56/28 9 Mustafa, Z. U. et al. 2022 Pakistan Cross-sectional study 636 NR 398/238 7 Pandey, M. et al. 2022 UK Cross-sectional study 299 NR 101/198 9 Roda, Silvia et al. 2022 Italy Cross-sectional study 22 61.36 ± 10.30 20/2 8 Routsi, C. et al. 2022 Greece Cross-sectional study 600 NR NR 8 Russo, A. et al. 2022 Italy Cross-sectional study 32 62.50 ± 10.99 21/11 8 Seitz, T. et al. 2022 Austria Cross-sectional study 117 57.2 ± 11.9 72/45 8 Torrecillas, Miriam et al. 2022 Spain Cross-sectional study 220 63.65 ± 12.69 169/51 8 Alenazi, T. A. et al. 2023 Saudi Arabia Cross-sectional study 118 60.97 ± 16.32 74/43 8 Alessandri, F. et al. 2023 Italy Cross-sectional study 138 62.20 ± 15.36 97/41 9 Bedenić, B. et al. 2023 Croatia Cross-sectional study 118 71 years (range 25–94) 78/40 8 Bonazzetti, C. t al. 2023 Italy Cross-sectional study 537 64.65 ± 11.15 402/135 9 Guanche Garcell, H. et al. 2023 Cuban Cross-sectional study 130 NR NR 8 Taysi, M. R. et al. 2023 Turkey Cross-sectional study 205 68.4 ± 13.1 119/86 8 AHRQ Agency for Healthcare Research and Quality, NR Not reported Section title: Characteristics Educational score: 3.9819676876068115 Domain: biomedical Document type: Study Language: en Table 2 Studies characteristics and quality. (Cohort study and case-control study) Study Published time Country Study design Patients Age Gender (male) NOS grade Cataldo, M. A et al. 2020 Italy Cohort study 57 62 ± 13 41/16 7 Garcia, Pedro David Wendel et al. 2020 European Cohort study 639 63 (53–71) 480/159 8 Zhang, H. et al. 2020 CHN Cohort study 38 64.76 ± 13.76 32/6 7 Massart, N. et al. 2021 France, Switzerland, Belgium Cohort study 4010 NR NR 8 Palanisamy, N. et al. 2021 India Cohort study 750 60 ± 17.71 562/188 8 Bartoszewicz, M. et al. 2023 Poland Cohort study 201 66.1 ± 12.1 114/87 8 Dupper, A. C. et al. 2022 US Case-control study 96 64.91 ± 9.51 57/39 8 NOS Newcastle-Ottawa Scale, NR Not reported Section title: Characteristics Educational score: 4.287830829620361 Domain: biomedical Document type: Study Language: en Table 3 Outcomes of meta-analysis Risk factors No. of studies Heterogeneity Analysis Statistical model statistical method Effect estimate P I² P (95%CI) Hypertension 10 70.4% 0.000 Random-effects OR 1.30(0.92,1.83) 0.131 Chronic pulmonary disease 11 23.4% 0.221 Fixed-effects OR 1.07(0.90,1.29) 0.443 Diabetes 12 50.2% 0.024 Random-effects OR 1.34(1.04,1.73) 0.022* Gender 14 0.0% 0.059 Fixed-effects OR 1.28(1.10,1.50) 0.006* Liver disease 6 2.3% 0.402 Fixed-effects OR 0.86(0.47,1.58) 0.635 Immunosuppressive diseases 5 29.9% 0.222 Fixed-effects OR 1.11(0.88,1.40) 0.375 Chronic kidney disease 6 0.0% 0.751 Fixed-effects OR 1.20(0.78,1.84) 0.411 Heart disease 10 0.0% 0.550 Fixed-effects OR 1.00(0.85,1.17) 0.957 Tocilizumab 9 34.3% 0.144 Fixed-effects OR 1.04(0.74,1.46) 0.815 Tumors 9 10.2% 0.350 Fixed-effects OR 1.04(0.78,1.37) 0.807 ECMO 4 74.1% 0.009 Random-effects OR 2.70(1.17,6.26) 0.020* Tracheal intubation 4 67.8% 0.025 Random-effects OR 8.68(4.68,16.08) < 0.001* Mechanical ventilation 2 0.0% 0.385 Fixed-effects OR 22.00(3.77,128.328) 0.001* Methylprednisolone 2 13.5% 0.282 Fixed-effects OR 2.24(1.24,4.04) 0.008* Methylprednisolone + Tocilizumab 2 71.0% 0.063 Random-effects OR 4.54(1.09,18.88) 0.037* Steroids 3 87.6% 0.000 Random-effects OR 1.17(0.15,9.23) 0.882 Remdesivir 2 54.4% 0.139 Random-effects OR 0.80(0.14,4.41) 0.794 Dexamethasone 2 10.2% 0.291 Fixed-effects OR 1.64(0.85,3.15) 0.139 Renal replacement therapy 2 97.9% 0.000 Random-effects OR 0.86(0.11,6.57) 0.882 Central venous catheterization 2 0.0% 0.559 Fixed-effects OR 9.33(3.06,28.43) < 0.001* Length of stay in ICUs 8 0.0% 0.712 Fixed-effects WMD 10.37(9.29,11.44) < 0.001* SAPS II score 2 58.3% 0.122 Random-effects WMD 6.43(0.23,12.63) 0.042* WMD Weight mean difference, OR Odds ratio, CI Confidence interval * P < 0.05 Section title: Gender Educational score: 4.0535383224487305 Domain: biomedical Document type: Study Language: en Fourteen studies [ 8 – 21 ] explored the correlation between gender and BSI in COVID-19 patients in ICUs. A pooled analysis showed that male COVID-19 patients in ICUs were 28% more likely to develop BSI (OR = 1.28, 95% CI: 1.10–1.50, P = 0.006, I 2 = 0.0%). Fig. 2 Forest plot of univariate data associating BSI risk with ( A ) gender; ( B ) SAPS II score; ( C ) diabetes; ( D ) hypertension and ( E ) chronic pulmonary disease for patients with COVID-19 in ICU Section title: SAPS II score Educational score: 4.094883441925049 Domain: biomedical Document type: Study Language: en Two studies analyzed the correlation between SAPS II scores and ICU-BSI in COVID-19 patients. Meta-analysis showed that higher SAPS II scores were positively correlated with an increased incidence of BSI in COVID-19 patients in ICUs (WMD = 6.43, 95% CI: 0.23–12.63, P = 0.042, I 2 = 58.3%). Section title: DM Educational score: 4.086632251739502 Domain: biomedical Document type: Study Language: en Twelve studies [ 8 – 13 , 15 – 18 , 20 , 21 ] investigated the correlation between DM and BSI in COVID-19 patients in ICUs. Most of these articles did not indicate whether DM was a risk factor for BSI. Our pooled analysis unraveled that DM increased the occurrence of BSI in COVID-19 patients in ICUs by 34% (OR = 1.34, 95% CI: 1.04–1.73, P = 0.022, I 2 = 50.2%). Section title: Hypertension Educational score: 3.989807367324829 Domain: biomedical Document type: Study Language: en There were conflicting results about the association between hypertension and BSI in COVID-19 patients in ICUs. Ten studies [ 8 , 10 – 13 , 16 – 20 ] were involved with mixed results. Meta-analysis demonstrated no correlation between hypertension and BSI in COVID-19 patients in ICUs (OR = 1.30, 95% CI:0.92–1.83, P = 0.131, I 2 = 70.4%). Section title: Chronic pulmonary disease Educational score: 4.073063850402832 Domain: biomedical Document type: Study Language: en Because COVID-19 mainly attacked the respiratory system, we extensively investigated the correlation between chronic pulmonary disease and BSI in COVID-19 patients in ICUs through 11 studies [ 8 – 12 , 15 – 17 , 19 – 21 ]. Meta-analysis showed no correlation between chronic pulmonary disease and BSI in COVID-19 patients in ICUs (OR = 1.07, 95% CI: 0.90–1.29, P = 0.443, I 2 = 23.4%). Section title: Liver disease Educational score: 4.071333885192871 Domain: biomedical Document type: Study Language: en Six studies investigated the correlation between liver disease and ICU-BSI in COVID-19 patients. Meta-analysis showed no correlation between liver disease and BSI in COVID-19 patients in ICUs (OR = 0.86, 95% CI: 0.47–1.58, P = 0.635, I 2 = 2.25%). Section title: Liver disease Educational score: 3.016348123550415 Domain: biomedical Document type: Study Language: en Fig. 3 Forest plot of univariate data associating BSI risk with ( A ) liver disease; ( B ) chronic kidney disease; ( C ) heart disease; ( D ) immunosuppressive disease and ( E ) tumors for patients with COVID-19 in ICU Section title: Chronic kidney disease Educational score: 4.058238983154297 Domain: biomedical Document type: Study Language: en Seven studies [ 9 – 11 , 15 , 19 – 21 ] investigating the association between chronic kidney disease and BSI in COVID-19 patients in ICUs were included. One article was excluded by sensitivity analysis and therefore six articles were included in the meta-analysis. It showed no correlation between chronic kidney disease and BSI in COVID-19 patients in ICUs (OR = 1.20, 95% CI: 0.78–1.84, P = 0.411, I 2 = 0.0%). Section title: Heart disease Educational score: 4.060513496398926 Domain: biomedical Document type: Study Language: en Ten studies [ 9 – 11 , 13 , 15 , 16 , 19 – 21 ] investigating the correlation between heart disease and BSI among COVID-19 patients in ICUs were included. Meta-analysis showed no correlation between heart disease and BSI in COVID-19 patients in ICUs (OR = 1.00, 95% CI: 0.85–1.17P = 0.957, I 2 = 0.0%). Section title: Immunosuppressive diseases Educational score: 4.0721755027771 Domain: biomedical Document type: Study Language: en All five studies showed no correlation between immunosuppression and ICU-BSI in COVID-19 patients. Meta-analysis also showed no correlation between immunosuppression and BSI in COVID-19 patients in ICUs (OR = 1.11, 95% CI: 0.88–1.40, P = 0.375, I 2 = 29.9%). Section title: Tumors Educational score: 4.059969425201416 Domain: biomedical Document type: Study Language: en Nine studies [ 8 – 11 , 17 , 19 – 21 ] investigating the correlation between tumors and BSI in COVID-19 patients in ICUs were included. Meta-analysis showed no correlation between tumors and BSI in COVID-19 patients in ICUs (OR = 1.04, 95% CI: 0.78–1.37, P = 0.807, I 2 = 10.2%). Section title: Tracheal intubation Educational score: 4.1045002937316895 Domain: biomedical Document type: Study Language: en Four studies were included to investigate the association between tracheal intubation and ICU-BSI in COVID-19 patients. Meta-analysis revealed that tracheal intubation increased the risk of BSI in COVID-19 patients in ICUs by nearly 9-fold (OR = 8.68, 95% CI: 4.68–16.08, P < 0.001, I 2 = 67.8%). Fig. 4 Forest plot of univariate data associating BSI risk with ( A ) tracheal intubation; ( B ) mechanical ventilation; ( C ) ECMO; ( D ) CVC; ( E ) RRT and ( F ) Length of stay in ICU for patients with COVID-19 in ICU Section title: Mechanical ventilation Educational score: 4.127668380737305 Domain: biomedical Document type: Study Language: en The correlation between mechanical ventilation and BSI in COVID-19 patients in ICUs was investigated by three studies . Since no heterogeneity was found ( P = 0.147, I 2 = 47.9%), a fixed-effects model was adopted and unraveled marked differences (OR = 4.98, 95% CI: 2.73–9.08, P < 0.001). After sensitivity analysis, the heterogeneity was greatly reduced ( P = 0.385, I 2 = 0.0%) when the study of Palanisamy, N et al. was excluded. The main source of heterogeneity might be the large sample size of their study, which tended to lead to unstable results compared to other studies with small sample sizes. Thus, this study was excluded because it led to a significant bias. The pooled analysis after exclusion using a fixed-effect model (OR = 22.00, 95% CI: 3.77–128.328, p < 0.001) showed statistically significant differences. The meta-analysis showcased that mechanical ventilation increased the risk of BSI by 22 times in COVID-19 patients in ICUs. The excluded study by Palanisamy, N et al. also showed that mechanical ventilation could increase the risk of BSI by 4-fold, in agreement with our results. Section title: ECMO Educational score: 4.09059476852417 Domain: biomedical Document type: Study Language: en Many critically ill patients have used ECMO for supportive care. Including four studies , we explored the correlation between ECMO and BSI among COVID-19 patients in ICUs. Meta-analysis manifested that ECMO increased the risk of BSI in COVID-19 patients in ICUs by nearly three times (OR = 2.70, 95% CI: 1.17–6.26, P = 0.020, I 2 = 74.1%). Section title: Central venous catheterization (CVC) Educational score: 4.069119453430176 Domain: biomedical Document type: Study Language: en Two studies investigated the correlation between CVC and ICU-BSI in COVID-19 patients. Meta-analysis showed that CVC increased the Catheter-related BSI (OR = 9.33, 95% CI: 3.06–28.43, P < 0.001, I 2 = 0.0%). Section title: Renal replacement therapy (RRT) Educational score: 4.068480491638184 Domain: biomedical Document type: Study Language: en Two studies investigating the correlation between RRT and BSI in COVID-19 patients in the ICU were included. Meta-analysis showed no correlation between BSI and RRT in COVID-19 patients in ICUs (OR = 0.86, 95% CI: 0.11–6.57, P = 0.882, I 2 = 97.9%). Section title: Length of stay in ICUs Educational score: 4.103285789489746 Domain: biomedical Document type: Study Language: en Eight studies were included [ 12 – 14 , 17 , 18 , 20 , 21 , 53 ], all of which showed a strong correlation between the length of stay in ICUs and the occurrence of BSI in COVID-19 patients in ICUs. A meta-analysis showed that the longer the ICU stay, the higher the risk of BSI in COVID-19 patients in the ICU (WMD = 10.37, 95% CI:9.29–11.44, P < 0.001, I 2 = 0.0%). Section title: Tocilizumab Educational score: 4.103457927703857 Domain: biomedical Document type: Study Language: en The correlation between Tocilizumab and BSI in COVID-19 patients was investigated in 10 studies [ 8 – 12 , 16 , 17 , 20 , 21 , 55 ]. One article was excluded by sensitivity analysis and therefore nine articles were enrolled in the meta-analysis. There was no correlation between Tocilizumab and BSI in COVID-19 patients in ICUs (OR = 1.04, 95% CI: 0.74–1.46, P = 0.815, I 2 = 34.3%). However, this may explain why Tocilizumab is widely used for severe and critically ill COVID-19 patients in ICUs under the guidance of guidelines. Fig. 5 Forest plot of univariate data associating BSI risk with ( A ) Tocilizumab; ( B ) Methylprednisolone; ( C ) Methylprednisolone and Tocilizumab combination; ( D ) Steroids; ( E ) Remdesivir and ( F ) Dexamethasone for patients with COVID-19 in ICU Section title: Methylprednisolone Educational score: 4.080850601196289 Domain: biomedical Document type: Study Language: en Two studies investigated the association between Methylprednisolone and ICU-BSI in COVID-19 patients. Meta-analysis signified that Methylprednisolone was linked with BSI in COVID-19 patients in ICUs (OR = 2.24, 95% CI: 1.24–4.04, P = 0.008, I 2 = 13.5%). Meanwhile, we found that the combination of Methylprednisolone and Tocilizumab significantly increased the risk for BSI in COVID-19 patients in ICUs (OR = 4.54, 95% CI: 1.09–18.88, P = 0.037, I 2 = 71%). Section title: Steroids Educational score: 4.068803310394287 Domain: biomedical Document type: Study Language: en All the studies on the risk of steroid use on ICU-BSI in COVID-19 patients were included, and the results were found only in 3 studies . Meta-analysis showed no correlation between steroid use and BSI in COVID-19 patients in ICUs (OR = 1.17, 95% CI: 0.15–9.23, P = 0.882, I 2 = 87.6%). This may be related to the fact that steroids are widely used as they are believed to improve the recovery of patients. Section title: Dexamethasone Educational score: 4.055051803588867 Domain: biomedical Document type: Study Language: en Two studies investigated the association between Dexamethasone and ICU-BSI in COVID-19 patients. Meta-analysis showed no correlation between Dexamethasone use and BSI in COVID-19 patients in ICUs (OR = 1.64, 95% CI: 0.85–3.15, P = 0.139, I 2 = 10.2%) . Section title: Remdesivir Educational score: 4.083388328552246 Domain: biomedical Document type: Study Language: en The correlation between Remdesivir and ICU-BSI in COVID-19 patients was investigated in 2 studies . Meta-analysis showed no correlation between Remdesivir and BSI in COVID-19 patients in ICUs (OR = 0.80, 95% CI: 0.14–4.41, P = 0.794, I 2 = 54.4%). This may be related to the fact that Remdesivir is considered a potent drug for the treatment of COVID-19, with significant efficacy, and therefore is more widely used for severe and critically ill patients in ICUs. Section title: Sensitivity analysis Educational score: 4.047084331512451 Domain: biomedical Document type: Study Language: en The stability of the results of the remaining articles was estimated by excluding each article in turn. Sensitivity analyses for gender, SAPS II score, DM, hypertension, chronic pulmonary disease, liver disease, heart disease, immunosuppressive disease, tumor, tracheal intubation, ECMO, CVC, RRT, length of stay in ICUs, and the use of Methylprednisolone, Steroids, and Remdesivir revealed that the results were relatively stable. In the sensitivity analysis of mechanical ventilation, the study by Palanisamy, N et al. greatly impacted the results, so the results were pooled after the exclusion of that article, and the results were more stable. Similarly, in the sensitivity study of chronic kidney disease, it was found that Massart, N et al. greatly influenced the results. After excluding the article and re-combining the results, the results were more stable. In the sensitivity study on the use of Tocilizumab, the study by Bonazzetti, C et al. greatly influenced the results. The results were more stable when the article was excluded, and the results were re-combined. The sensitivity analyses of other factors implied stable and insignificant changes, so these studies were retained. Section title: Publication bias Educational score: 3.783186674118042 Domain: biomedical Document type: Study Language: en Publication bias was examined using the Egger test for the risk factor containing ≥ 10 articles. There was no publication bias for men ( P = 0.187), DM ( P = 0.142), hypertension ( P = 0.396), heart disease ( P = 0.592), and chronic pulmonary disease ( P = 0.671). Section title: Publication bias Educational score: 2.8554940223693848 Domain: biomedical Document type: Study Language: en Fig. 6 Publication bias of univariate data associating BSI risk with ( A ) gender; ( B ) diabetes; ( C ) chronic pulmonary disease; ( D ) hypertension and ( E ) heart disease for patients with COVID-19 in ICU Section title: Discussion Educational score: 4.106521129608154 Domain: biomedical Document type: Study Language: en In this meta-analysis, we aimed to identify risk factors for BSI in COVID-19 patients in ICUs. Among the studies with available data, 55 published English studies [ 3 , 5 – 58 ] investigating risk factors associated with BSI in COVID-19 patients in ICUs were included. Our findings showed that male, DM, tracheal intubation, mechanical ventilation, CVC, ECMO, Methylprednisolone use, higher SAPS II score, and longer ICU stay were risk factors for ICU-BSI in COVID-19 patients. In addition, hypertension, chronic pulmonary disease, liver disease, chronic kidney disease, heart disease, immunosuppression, tumor, RRT, and the use of Tocilizumab, Steroids, and Remdesivir neither increased nor decreased the risk of ICU-BSI in COVID-19 patients. Section title: Patient-related factors Educational score: 4.107047080993652 Domain: biomedical Document type: Study Language: en Our analyses showed that male COVID-19 patients were at a higher risk of BSI in ICUs and that males also made up most of the ICU admission population. A previous study by Zamora-Cintas, M. et al. highlighted that male patients had a higher risk of BSI, in line with our results. COVID-19 virus infection mainly affects pulmonary function, resulting in more patients with pulmonary dysfunction being admitted to the hospital, and more severe patients need to be admitted to ICUs, which makes them more susceptible to BSI. However, we did not study whether smoking was a risk factor for BSI in COVID-19 patients in ICUs and the proportion of men who smoke., which might require more data support. Our findings also showed that the SAPS II score directly reflected the risk of BSI in COVID-19 patients in ICUs, in agreement with the findings of Massart, N et al. . SAPS II score, as an important evaluation component in ICUs, to some extent, also reflects infection indicators, which is directly related to our study. In short, a higher SAPS II score indicates a more severe condition and a worse prognosis . DM is a common chronic underlying disease in clinical practice. Our results showed that DM was also an associated risk factor for ICU-BSI in COVID-19 patients. This may be related to diverse complications associated with DM and the poor resistance of diabetic patients, which makes them susceptible to a variety of related infections and directly increases the risk of BSI . Section title: Treatment-related factors Educational score: 4.324629783630371 Domain: biomedical Document type: Study Language: en Our findings suggested that tracheal intubation substantially increased the risk of ICU-BSI in COVID-19 patients, in support of the findings of Bonazzetti, C et al. and Rollas, Kazim et al. . Tracheal intubation is a common resuscitation technique in ICUs and is essential to save patients in respiratory distress. It ensures that the patient receives an adequate supply of oxygen and provides mechanical ventilation support to maintain normal respiratory function . This makes mechanical ventilation support also a possible risk factor for BSI in COVID-19 patients in ICUs. Invasive treatment is highly likely to cause airway damage, and tracheal intubation may introduce bacteria or other pathogens, increasing the risk of infection in patients. It is also easy for micro-aspiration to occur after tracheal intubation, leading to lung infections . All these directly increase the risk of BSI. COVID-19 has become a specific infection that involves the pathophysiology of the lungs, including endothelial and epithelial changes, pulmonary embolism, and microvascular thrombosis. In addition, secondary infectious injury can cause acute lung injury and prolong mechanical ventilation . Zhang, J et al. showed that multiple invasive treatments were important risk factors for BSI. Early extubation and regular assessment of infection should be done, therefore early anti-infective therapy is important . CVC is widely used in the resuscitation of severe and critically ill patients, which is conducive to the measurement of central venous pressure, long-term medication, and large and rapid rehydration, thus preventing venous damage and repeated puncture. However, a common complication of CVC is deep vein thrombosis, which also leads to the invasion of external bacteria and infection. Patients present with persistent low-grade fever, and the simultaneous presence of bacteria and thrombus can exacerbate the infection . Our study revealed that prolonged CVC substantially increased the risk of ICU-BSI in COVID-19 patients. Therefore, there is a need for timely monitoring of the situation and increased measures for infection control and nursing care for CVC. ECMO serves as an important therapeutic tool to provide continuous extracorporeal respiratory and circulatory function for critically ill patients presenting with cardiopulmonary failure. Some studies showed that infections were highly susceptible to occurring after the use of ECMO, which was related to the fact that patients with low immunity were susceptible to systemic hematogenous infections, thus dramatically increasing the risk of fungal infections . This was in general agreement with the results of our study. Meanwhile, ECMO may result in renal failure in about 50% of patients, which may require RRT . However, our study found that RRT was not a risk factor for ICU-BSI in COVID-19 patients, which may need to be supported by more data. In particular, intuitive data in our study pointed out that the longer the treatment duration in ICUs, the higher the risk of BSI in COVID-19 patients. The possible reasons are as follows: first, the treatment time reflects the severity of the patient’s condition, and a longer ICU stay may mean that the patient’s condition is more critical; second, the longer the treatment time, the higher the chance of nosocomial infections , which is closely related to the prolonged use of antibiotics and ward management; third, severe and critically ill patients in ICUs have low resistance and need to be left with various passages during treatment, and most COVID-19 patients have coughing symptoms, which is prone to aerosol dissemination and transmission of infectious disease between the patients, thus greatly increasing the risk of BSI . Section title: Medication-related factors Educational score: 4.177585124969482 Domain: biomedical Document type: Study Language: en In our study, the use of Tocilizumab, Remdesivir, Steroids, and Dexamethasone did not correlate with the risk of BSI in COVID-19 patients in ICUs, but the use of Methylprednisolone and the combination of Methylprednisolone and Tocilizumab directly increased the risk of ICU-BSI in COVID-19 patients. This is associated with the fact that patients receiving glucocorticoid therapy are more likely to require ventilatory support, vasopressors, and RRT . Glucocorticoids are widely used and effective drugs during hospitalization, especially in ICU, due to their anti-inflammatory and immunosuppressive effects. Glucocorticoids inhibit the inflammatory chemotaxis of cells and the rate of phagocytosis to reach inflammation sites. In addition, glucocorticoids increase the stability of cells so that cell membranes are less likely to rupture, and cells are less likely to release lysosomal enzymes to phagocytose bacteria to destroy inflammatory foci, thus decreasing the body’s immunity and making it susceptible to viral or bacterial infections . Glucocorticoids will also directly inhibit the body’s immune function, thus inhibiting the body’s fever, so that the fever symptoms are not obvious, which in turn masks the severity of the disease and delays the diagnosis and treatment, leading to further deterioration of the condition . Moreover, glucocorticoids also inhibit mucosal exudation and inflammatory exudation. For patients with respiratory tract infections, glucocorticoids inhibit the exudation of inflammatory secretions, so that patients reduce coughing, which is not conducive to discharging bacterial sputum out of the body through coughing. Additionally, it delays the detection and treatment, thus aggravating the infection and increasing the risk of BSI greatly . Therefore, it is crucial to monitor the use of glucocorticoids rationally according to the condition . Section title: Incidence of ICU-BSI in COVID-19 patients Educational score: 4.109106063842773 Domain: biomedical Document type: Study Language: en Meta-analysis unraveled that the incidence of BSI in COVID-19 patients in ICUs was 19.9%, similar to the currently reported 10–50% incidence rate. Compared with previous studies, in which 7% of COVID-19 hospitalized patients may experience BSI , the incidence of BSI in COVID-19 patients in ICUs increased nearly threefold. The incidence of ICU-BSI in COVID-19 patients varied in different studies, mainly because the occurrence of BSI lies in the detection of blood cultures. Also, it is somewhat difficult to exclude sampling contamination and detection contamination, and most patients in ICUs receive various types of medications, which may affect the detection of BSI . Section title: Strengths and limitations Educational score: 3.9908196926116943 Domain: biomedical Document type: Review Language: en This is the first systematic review analyzing risk factors for ICU-BSI in COVID-19 patients, and the data were reviewed by two investigators to ensure accuracy. By incorporating an extensive array of papers with high quality, our findings provide an accurate and reliable framework for promptly identifying the risk of BSI occurrence in COVID-19 patients in ICUs. In addition, our findings provide more comprehensive references of risk factors for ICU-BSI in COVID-19 patients for clinical treatment, which is a guide for early prevention of BSI. Section title: Strengths and limitations Educational score: 3.9978926181793213 Domain: biomedical Document type: Study Language: en However, some limitations need discussion. First, the studies covered diverse ethnicities, populations, methods, and periods of investigation, which is reflected in heterogeneity. However, this may be due to differences in study design rather than actual differences in outcome measures. Therefore, we used sensitivity analyses and random-effects models to verify the result stability in the presence of high heterogeneity. Second, the diagnosis of BSI in COVID-19 patients treated with Tocilizumab may be difficult because patients often do not have fever and have low serum levels of typical inflammatory markers, requiring further study. Third, Data on diseases such as diabetes and oncology did not have specific types of data, so specific rich data are needed to study their association with BSI. Fourth, few of the included studies analyzed the impact of post-invasive treatment care measures on the occurrence of BSI in COVID-19 patients in ICUs. Therefore, in the future, more assessments of the impact of treatment details on ICU-BSI in COVID-19 patients and randomized controlled trials are needed to enhance the reliability. Section title: Conclusion Educational score: 4.062220573425293 Domain: biomedical Document type: Study Language: en Our findings showed that males, higher SAPS II scores, DM, tracheal intubation, mechanical ventilation, ECMO, CVC, longer ICU stays, and Methylprednisolone use increased the risk of ICU-BSI in COVID-19 patients. It is imperative for future research to integrate these factors into a comprehensive predictive assessment framework to identify and intervene promptly in COVID-19 patients at high risk for ICU-BSI to improve treatment outcomes and promote patient health recovery. Section title: Supplementary Information Educational score: 1.4485911130905151 Domain: biomedical Document type: Other Language: en Supplementary Material 1. | Study | biomedical | en | 0.999998 |
PMC11697695 | Section title: 1. Introduction Educational score: 4.5079145431518555 Domain: biomedical Document type: Review Language: en Self-contained electrochemical nanotechnologies empowering direct single-cell studies have long been pursued to deepen our knowledge of cellular heterogeneity and behaviors as well as to promote precise pathological diagnosis and therapeutic strategies [ 1 – 3 ]. Accessing the native cytosol by a transmembrane nanoelectrode is the prerequisite for subsequent electrochemical decipher of the hidden biomolecular information and intracellular dynamics . After penetration, application of potential-resolved electrochemistry at the conducting nanotips could trigger redox reactions that correlate with specific endogenous species, which is at the heart of current single-cell electroanalysis [ 6 – 8 ]. Nevertheless, to yield electrical signals, occurrence of Faradic reactions at specific potentials and wired circuits are the necessity, which severely restricts this methodology to redox-involved events. To take it a step further, scientists have endeavored to exploit new nanoelectrochemistry and mechanism [ 9 – 12 ]. For example, using a single nanopipette, confined electrochemiluminescence has recently been exploited for wireless intracellular analysis . Photoelectrochemistry of engineered organic molecules and semiconductor hybrid has been used for studying intracellular oxidative stress . Utilization of the ionic current rectification could even realize the detection of intracellular H 2 O 2 and microRNA . Section title: 1. Introduction Educational score: 4.399272918701172 Domain: biomedical Document type: Review Language: en Cell interior functions as a viscoelastic material, and cellular viscosity is crucial for the ubiquitous diffusion-dependent biological reactions and cascades . While changes in cellular viscosity has been correlated with many pathologies and malfunctions , the homeostatic nature of cellular viscosity and the intrinsic viscosity regulation mechanism as well as its potential biochemical/biophysical implications are still not well understood. Caragine et al. recently reported observation of the movement and fusion of cellular components for investigation of the viscous properties of the cell . Persson et al. then revealed that the cell tunes cytosolic viscosity to counter alternation of temperature and energy . To perform these, studies demand the ability to measure viscosity directly in a living cell, which could provide a benchmark for monitoring the viscosity and identifying the impacts of specific diseases on the cellular material properties. Despite their respective advantages, existing methods, e.g., fluorescent and rotational magnetic ones , are in concerns of low spatiotemporal resolution, biocompatibility, or bioorthogonality issues, such as possible cytotoxicity or destructiveness of the probe, disturbance of the intrinsic cellular chemistry, and their photobleaching or degradation inside cells. To date, scientists still lack an ideal single-cell viscometer that is highly simple, durable, and spatiotemporal-resolved. Section title: 1. Introduction Educational score: 4.299144268035889 Domain: biomedical Document type: Study Language: en Originally found in nature, iontronics has rapidly evolved as an advanced technology based on sophisticated control of ions as signal carriers, underpinning the operating rationale of aqueous circuits made of rationally designed nanostructures and thereon the controllable ionic transport [ 21 – 23 ]. Working in aqueous environments, iontronic devices have shown to be promising for sensing, logic circuiting, and brain-machine interfacing. Herein, using the θ -type nanopores , we report an accessible iontronic single-cell viscometer with a high spatiotemporal resolution (see Supporting Information for experimental details). The nanotool was operated upon the potential-directed reversible ionic motion within the nanoscale cytosolic fluid bridging two adjacent nanopores, which would create recordable ionic currents of nanoampere level. Using a theory that describes how viscosity affects the current, the altered cellular viscosity and differentiable signals could be linked, and the accurate viscosity at specific time and position could also be inferred. Glucose deprivation and heat shock experiments further revealed the practicability of this nanotool of high spatiotemporal resolution. This work achieves an accessible single-cell viscometer and sheds light on futuristic study of single-cell material property and assessment of associated chemotherapeutic effects. Section title: 2.1. Operation Rationale and Measurement Educational score: 4.232089996337891 Domain: biomedical Document type: Study Language: en As illustrated in Figure 1 (a), the nanotool was used to position at the specific intracellular site of a single living cell, and the local viscosity was transduced by the directional ionic motion driven by a step pulse voltage (SPV) from a patch-clamp system. Alternative application of the SPV (−1.0 V/+1.0 V) could induce reversible ionic motion passing through the two adjacent apertures, while the very short application time of ~400 ms was set to minimize the influence upon both the intracellular microenvironment and the interfacial charge property of the two lumens. According to the Nernst-Planck equation and Stokes-Einstein relation , the ionic diffusion coefficient relies closely upon the solution viscosity (Eqs. S1–S10), indicating that the ionic current is controlled by the medium viscosity. In the present case, as illustrated in Figure 1 (b), the essential resistance (RE), consisting of those of nanopipettes, electrodes, and electrolyte, was kept unchanged throughout the study, whereas the resistance of the cytosol around the nanotips (RC) was the only variate during the measurement, suggesting the variation of the acquired ionic signal solely originated from the varied RC associated with the local viscosity. Figure 1 (c) depicts the side-view (upper) and top-view (bottom) scanning electron microscopy (SEM) micrographs of the as-used laser-pulled double-barrel quartz capillaries with θ -type nanopores. The two compartmentalized semielliptical orifices possessed similar dimensions of 104 ± 6 nm , which were separated by a quartz septum of 32 ± 3 nm in width. Incidentally, to ensure better performance, similar devices were preferred, which could be easily screened via the SPV-induced ionic responses, as reflected in and discussed with Figures S1–S2 , respectively. Section title: 2.1. Operation Rationale and Measurement Educational score: 4.267630577087402 Domain: biomedical Document type: Study Language: en The practical applicability of the nanotool was then in vitro studied. Previous reports had revealed the potential-directed delivery or sampling functions of nanopipettes , the function of which was initially investigated using HEPES milieu containing saturated fluorescein. As shown in Figure 2 (a), such an effect was verified by 20 min electroosmosis under -1.0 V, which led to obvious green fluorescence of fluorescein within the nanotool. By contrast, as shown in Figure 2 (b), the SPV test under the same conditions could not induce the appearance of the fluorescence, indicating the absence of fluorescein within the nanotool. This was due to the very short SPV time, i.e., 400 ms, and the rapid application of inverse voltage. Next, the responses of the nanotool were acquired in specific glycerin-HEPES milieus of different viscosities ranging from 1.0 to 320 cP (Table S1 ), which were set in advance with the assistance of a commercial viscometer. As shown by the differentiable i - t curves in Figure 2 (c), the generated ionic signals were gradually inhibited from ca. 6.7 to ca. 1.0 nA, which could be attributed to the reduced ionic diffusion coefficient with the increase in viscosity. Figure 2 (d) shows the derived linear relationship between the ionic signals and the corresponding viscosities. Incidentally, the effects of possible ionic variation (Figure 2 (e)), pH change (Figure 2 (f)), and adsorption (Figure 2 (g)) were also excluded. As shown in Figure 2 (e), the HEPES milieu of 60 cP containing 130 mM K + and different Na + concentrations of (i) 2.5 mM, (ii) 10 mM, and (iii) 15 mM were tested, and hardly any signal variation could be observed. Besides, to study the possible pH variation effect, as shown in Figure 2 (f), HEPES milieu of 60 cP with pH of 6.6, 7.4, and 7.8 had almost no effect on the response of the nanotool . To study the possible adsorption effect, the nanotool was sequentially immersed into the cell lysate for 10 min and then tested for three repeated times. As shown in Figure 2 (g), the nearly identical signals indicated that there was little adsorption on the nanotool. Besides, the small droplet experiments further confirmed not only its capability to distinguish different viscosities but also its stability during the repeated measurements . Section title: 2.2. Cell Spatial-Resolved Measurement Educational score: 4.115510940551758 Domain: biomedical Document type: Study Language: en Its capability for in vivo spatial-resolved studies was then studied through targeting specific subcellular regions. Exemplified by three individual A549, MCF-7, and HeLa cells, three specific subcellular regions, i.e., the lysosome-dense, mitochondrion-dense, and the near-nuclear ones, were chosen. As shown in Figures S4–S6 , it was observed that the penetration into the cytoplasm by the nanotool could not induce the change of the cellular morphologies. Our earlier staining studies had indicated the minimal destructiveness of such nanotools without affecting the cytomembrane integrity and cellular viability , which was also confirmed in the present case of double-barreled nanopores . Three different dyes, i.e., Lyso-Tracker Green, MitoGreen, and Hoechst 33342, were used to locate lysosomes, mitochondria, and nucleus, respectively. The abovementioned three subcellular locations of three different cells were then targeted as represented in Figures 3 (a)– 3 (c) and Figures S12–S14 , with 25 cells per group. The corresponding current during the nanotip penetrated throughout the cell membrane Section title: 2.2. Cell Spatial-Resolved Measurement Educational score: 4.200462341308594 Domain: biomedical Document type: Study Language: en As shown in Figure S15 and Figure 3 (d), the ionic responses of these three positions could be, respectively, measured with the derived average viscosities of ca. 58 cP, 55 cP, and 93 cP for A549 cells, of ca. 55 cP, 68 cP, and 99 cP for MCF-7 cells, and of ca. 55 cP, 57 cP, and 99 cP for HeLa cells. Although significantly biased lysosomal viscosities of ca. 65-130 cP and mitochondrial viscosities of ca. 62-120 cP [ 15 , 30 – 32 ] had been reported by respective optical methods, the medium viscosities in the mitochondrion-dense and lysosome-dense regions are largely unknown. Our statistical results revealed the less deviated viscosities around these organelles. In particular, as compared to those of the two subcellular regions, our results further disclosed the highest viscosities ranging from ca. 80 to 130 cP in the near-nuclear region. This phenomenon may be due to the dense distribution of the cytoskeleton next to the nucleus. Tubulin, the main component of the cytoskeleton, has been reported to have great influence on the local cytoplasmic viscosity . Section title: 2.3. Cell Temporal-Resolved Measurement Educational score: 4.113471984863281 Domain: biomedical Document type: Study Language: en The nanotool was then implemented for in vitro temporal-resolved studies via subjecting the representative HeLa cells to glucose deprivation and heat shock experiments, respectively. Intracellular deprivation of glucose was initially performed to induce the enhanced cytoplasmic viscosity . Experimentally, after 12 h culture in glucose-containing Dulbecco’s modified Eagle medium (DMEM), the HeLa cells were treated with glucose-free DMEM for 30 min for glucose deprivation, followed by collection of the ionic responses every 15 minutes within the cytoplasm. As shown in Figure 4 (a), the targeted cell well maintained its morphology during the 30 min detection. As compared to the case of normal HeLa cells with the viscosity fluctuation around ca. 60 cP , Figure 4 (b) records the obvious varied viscosity responses with increase from ca. 7 to 106 cP with 10 treated HeLa cells per group . Section title: 2.3. Cell Temporal-Resolved Measurement Educational score: 4.193419456481934 Domain: biomedical Document type: Study Language: en Stress granules (SGs) are a membraneless organelle composed of protein-wrapped RNA, which undergo a nucleated assembly mechanism under stress conditions (like oxidative stress, heat shock, and ultraviolet irradiation) . Formation of SGs is closely related to many diseases, e.g., tumor apoptosis and Alzheimer’s disease; hence, exploration of SG-associated physiological indexes is of great significance [ 37 – 39 ]. Heat shock experiment was then conducted with treatment at 42°C for 70 minutes and then 37°C for 30 minutes to induce the formation of SGs , which was proven via an indirect immunofluorescence assay, with the assistance of Hoechst 33342 to stain the nucleus . As compared in Figure 4 (c), no green fluorescence in the normal HeLa cell indicated the absence of SGs in the cytoplasm, whereas the appearance of green fluorescence around the blue nucleus indicated the assembly of intracellular SGs (white arrow). After 60 min recovery, the disappearance of the green granules indicated the disassembly of SGs [ 18 , 37 – 40 ]. As shown in Figure 4 (d) and Figure S18 , decreased viscosity of ca. 40 cP was measured after the formation of SGs from heat shock. With the increase in time, the increase in the viscosity was gradually observed and recovered to normal level of ca. 60 cP within 60 minutes. This phenomenon could be attributed to the removal of stress conditions and thus the depolymerization of SGs, which was also confirmed with dark field observation. As recorded in Figure S19 , there were many bright particles in the heat-shocked cells, which then gradually disappeared within the same 60 minutes. Section title: 3. Discussion Educational score: 4.252358436584473 Domain: biomedical Document type: Study Language: en To conclude, we have devised a high spatiotemporal iontronic single-cell viscometer based on the potential-controlled electroosmotic manipulation of ionic flow confined within the θ -type nanopores. The miniaturized θ -type nanotip permits cytomembrane penetration under physiological conditions with cell-context preservation and allows the reversible ionic motion within the two adjacent nanopores; the generation of the varied ionic currents could be intimately correlated with the altered intracellular viscosities. Significantly, practical spatial studies disclosed not only the less deviated medium viscosities of the subcellular lysosome- and mitochondria-dense regions than those of the organelles themselves but also the highest viscosities in the near-nuclear region among the studied three subregions. Exemplified by the glucose deprivation and heat shock experiments, changes of cellular viscosity were further temporally revealed. As compared to current implementations of θ -type nanopores (Table S2 ), this work presented a new application scenario, which should potentially contribute to the futuristic investigation of single-cell viscosity, single-cell diagnostics, and assessment of specific drugs and chemotherapies. Section title: 4.1. Reagents and Materials Educational score: 1.5995992422103882 Domain: biomedical Document type: Other Language: en Sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl 2 ), glycerin, calcium chloride anhydrous (CaCl 2 ), 2-[4-(2-hydroxyethyl) piperazin-1-yl] ethanesulfonic acid (HEPES), fluorescein, paraformaldehyde (POM), Tween-20, silver wire ( Φ 0.2 mm), and other reagents were purchased from Sinopharm Co., Ltd. (Shanghai, China). Bovine serum albumin (BSA) was purchased from Sigma-Aldrich (St. Louis, MO, USA) (Sigma). All aqueous solutions were prepared in deionized water (Millipore) with a resistivity of 18.2 M Ω ∗ cm . 1x PBS (phosphate-buffered solution, 10 mM, pH 7.2-7.4), Triton X-100, 2.2 mM EDTA solution containing 0.25% trypsin, Hoechst 33342, propidium iodide (PI), MitoGreen, HeLa cells, A549, and MCF-7 cells were purchased from Keygenbio Co., Ltd. (Nanjing, China). Lyso-Tracker Green was from Beyotime Biotechnology (China). Fetal Bovine Serum (FBS), DMEM, and normal RPMI 1640 medium were purchased from Gibco (USA). Rabbit monoclonal anti-TIA-1 antibody [EPR9304] AB 140595 and goat anti-rabbit secondary antiserum lgG H&L (Alexa Fluor® 488) ab 150077 were both obtained from Abcam (USA). Section title: 4.2. Experimental Setup and Data Acquisition Educational score: 4.099228858947754 Domain: biomedical Document type: Study Language: en All ionic current measurements were recorded using a Multiclamp 700B amplifier (Axon Instruments, USA) in voltage-clamp mode with the Digidata 1550 digitizer (Molecular Devices) and a PC equipped with pCLAMP10.5 software (Molecular Devices). The current-voltage ( I - V ) curves were recorded by sweeping the voltage from -1.0 V to +1.0 V and recorded with a sampling frequency of 5 kHz. A three-dimensional MP-225 micromanipulator (Sutter Instrument, Novato, CA) equipped with an inverted microscope (Ti2-E, Nikon, Japan) was applied for the precise control of the nanopipette to insert into cells under observation. The I - V and I - t recordings were plotted with Clampfit 10.5 software and OriginLab. Scanning electron microscopic (SEM) characterization was performed on a JSM-7800F instrument (JEOL, Japan), equipped with Stage Top Incubator (STX-EN-01, Tokai Hit Co., Ltd). Section title: 4.3. Fabrication of the Nanodevice Educational score: 4.15672492980957 Domain: biomedical Document type: Study Language: en Quartz theta (O.D.: 1.2 mm, I.D.: 0.90 mm; 7.5 cm length) was purchased from Sutter Instrument and were laser-pulled by using a P-2000 pipette puller (Sutter Instrument, Novato, CA, USA) with a two-line program containing the following parameters: line 1: heat = 900 , Fil = 4 , Vel = 30 , Del = 180 , and pull = 40 , and line 2: heat = 950 , Fil = 3 , Vel = 20 , Del = 180 , and pull = 120 . To ensure the reproducibility of nanotip geometry, the variation of pulling time was controlled within 0.2 second. Prior to electrochemical viscosity measurement, silver wires were immersed into the commercially 84 disinfectant for 25 min at room temperature to fabricate home-made Ag/AgCl wire electrodes. Then, two Ag/AgCl electrodes were, respectively, served as the working electrode and counter electrode as well as reference electrode inserted into two pores of the θ -nanopipette, which were then backfilled with NaCl 5 mM, KCl 120 mM, MgCl 2 4.5 mM, and HEPES 10 mM ( pH = 7.4 ). Section title: 4.4. Cell Culture Educational score: 3.960195302963257 Domain: biomedical Document type: Study Language: en HeLa cells and A549 cells were cultured with DMEM in the presence of 10% FBS and antibiotics (penicillin and streptomycin) and maintained at 37°C in 5% CO 2 /95% air, while MCF-7 cells were cultured with normal RPMI 1640 medium in the presence of 10% FBS and antibiotics (penicillin and streptomycin) and maintained at 37°C in 5% CO 2 /95% air. Section title: 4.5. Cell Lysate Educational score: 4.151191711425781 Domain: biomedical Document type: Study Language: en HeLa cells were digested using the trypsin enzyme and then centrifuged with 1000 rpm for 5 min. Next, the sediment was diluted with 1 ml 1X PBS, and the cell density was then calculated via countess II (Life, the USA). Finally, the cell lysate was obtained by treatment with the diluted cell solution at 0°C using an ultrasonic cell crusher noise isolating chamber (Anxiu, China), with the program as follows: 35% power, 2 min and rod 6, and ultrasound performed for 5 s and paused for 5 s. Section title: 4.6. Cell Vitality Measurement Educational score: 3.294278144836426 Domain: biomedical Document type: Study Language: en The cellular vitality tests were performed via the dye staining experiments with the usage of propidium iodide (PI) and Hoechst 33342 , respectively. Section title: 4.7. Fluorescence Observation Educational score: 4.0394158363342285 Domain: biomedical Document type: Study Language: en To locate lysosomes, Lyso-Tracker Green was diluted to 1/9250 ( V / V ) with DMEM, and A549, MCF-7, and HeLa cells were washed three times with 1x PBS. Next, the cells were incubated in the diluted Lyso-Tracker Green solution at room temperature for 30 minutes. To locate mitochondria, MitoGreen was diluted to 1/1000 ( V / V ) with PBS, and A549, MCF-7, and HeLa cells were washed three times with 1x PBS. Next, the cells were incubated in the diluted MitoGreen solution at room temperature for 15 minutes. To locate the nucleus, the cells were washed three times with 1x PBS and then stained with Hoechst 33342 at room temperature for 10 min . Section title: 4.8. Characterization of the Formation of Intracellular Stress Granules Educational score: 4.173600673675537 Domain: biomedical Document type: Study Language: en TIA-1 is an RNA-binding protein, which is regarded as playing a key role in SG assembly . Thus, SG degradation is able to be observed via tracking the statement of TIA-1 when the stress conditions alleviated. Experimentally, HeLa cells growing on the cell culture dish were fixed with 4% paraformaldehyde in PBS for 10 min at room temperature and then permeabilized with 0.3% TritonX-100 for 10 min, followed by incubation in blocking buffer (5% BSA and 0.1% Tween-20 in PBS) for 1 h before the addition of primary antibodies. A primary antibody of rabbit monoclonal anti-TIA-1 and goat anti-rabbit secondary antiserum lgG H&L were, respectively, diluted to 1 : 300 ( V / V ) and 1 : 1000 ( V / V ) using the blocking buffer. To characterize the stress granules, the heat-shocked HeLa cells were incubated in the diluted primary antibody solution at 4°C overnight. Then, after washing several times in PBS, the cells were incubated in diluted solution of the secondary antibody for 1 h in the dark. Then, the cells were rinsed three times with PBS and stained with Hoechst 33342 for 5 min to locate the nucleus . Section title: 4.9. Observation of Heat-Shocked Cells under Dark Field Educational score: 3.851527452468872 Domain: biomedical Document type: Study Language: en Heat-shocked HeLa cells (42°C for 70 minutes and 37°C for 30 minutes) were observed and photographed by inverted microscopy (IX71, Olympus) coupled with a true-color digital camera (Olympus DP80, Japan) in 10% FBS 1x PBS solution . | Review | biomedical | en | 0.999996 |
PMC11697698 | Section title: Introduction Educational score: 4.120882987976074 Domain: biomedical Document type: Review Language: en Pharmaceuticals are essential in healthcare for treating various conditions, but they must be administered carefully to avoid adverse effects. Concerns about environmental contamination have risen as pharmaceuticals and their metabolites, classified as “emerging contaminants” for over 15 years, are frequently detected in wastewater, eventually entering natural water sources through industrial discharge and human excretion . Developed nations often face issues with lifestyle drug misuse, while developing countries struggle with counterfeit life-saving drugs . Pharmaceuticals in wastewater, with concentrations from micrograms to nanograms per liter, pose risks as current treatment systems fail to remove them entirely, allowing these compounds and their by-products to reach drinking water sources . Moreover, organic solvents in pharmaceutical analysis contribute significantly to environmental and health issues, especially low-boiling-point solvents like n-hexane, toluene, methylene chloride, benzene, chloroform, methanol, ethanol, and acetonitrile, which have known toxic effects . For instance, benzene can cause anemia, hexane is a neurotoxin, and prolonged exposure to chloroform can damage the liver and kidneys. Recognizing the severe impact of these solvents, some are classified as “red solvents” by Pfizer due to their high toxicity . Section title: Introduction Educational score: 3.706712245941162 Domain: biomedical Document type: Other Language: en Fluorimetric techniques offer an efficient solution to reduce medication toxicity and solvent use. They require minimal sample preparation and solvent consumption. Simple instruments can detect fluorescent compounds at concentrations up to a thousand times lower than absorption spectrophotometry. By dissolving samples in a suitable solvent, chemical changes can make non-fluorescent compounds detectable, and applicable to both organic and inorganic substances. Section title: Introduction Educational score: 3.935917615890503 Domain: biomedical Document type: Other Language: en Medicines are essential for treating and preventing diseases, and for maintaining public trust in healthcare systems. However, all medications carry a risk of side effects, making it crucial to monitor both intended and unintended outcomes to balance risk and efficacy. Detecting impurities in both active ingredients and formulations is therefore vital . Early identification of unexpected substances, especially in new drugs, is important to reduce health risks. Pharmaceuticals, even at low doses, can be highly active, with contraceptives at nanograms/Liter (ng/L) levels potentially disrupting endocrine systems in municipal water. Excretion and improper disposal release pharmaceuticals into the environment, highlighting the need for effective detection to minimize their environmental and animal toxicity [ , , ]. Section title: Introduction Educational score: 3.954124689102173 Domain: biomedical Document type: Review Language: en As pharmaceutical research advances, the development of novel and highly selective analytical techniques is crucial for faster, more efficient methods that offer cost savings and reduce solvent consumption. This work evaluates recent quantitative analytical methods and their applications in pharmaceutical analysis, which are essential for quality control and require quick, reliable, and clear results. Key techniques used for the quantitative analysis of pharmaceutical compounds include capillary electrophoresis (CE), high-performance liquid chromatography (HPLC), Ultraviolet–Visible (UV/Vis) spectrophotometry, fluorimetry, titrimetry, voltammetry (in electroanalytical methods), thin-layer chromatography (TLC), gas chromatography (GC), and vibrational spectroscopies . Fig. 1 Traditional analytical techniques. Fig. 1 Section title: Introduction Educational score: 4.522337913513184 Domain: biomedical Document type: Review Language: en UV/Vis spectrophotometry is a widely used method in pharmaceutical analysis, measuring how much ultraviolet (UV) (190–380 nm) or visible (380–800 nm) radiation a chemical absorbs. It works by assessing the relationship between two beams of UV light, where absorption occurs when the energy matches the electronic transitions in the molecule. Combining UV and Vis spectrophotometry offers convenience due to its rapid analysis and ease of use . Fluorimeters and spectrofluorometers, which measure fluorescence (FL), offer higher sensitivity compared to other absorption methods. The limitations of FL spectroscopy arise from the sensitivity of detectors to different wavelengths and variations in energy intensity. Infrared (IR) spectroscopy, covering near IR (0.8–2 μm), mid IR (2–15 μm), and far IR ranges, provides detailed structural information of organic and inorganic compounds, with the fundamental 2–15 μm range being most informative for chemical structure analysis . Nuclear Magnetic Resonance (NMR) spectroscopy examines molecular structure at the atomic level, particularly using the 1 H and 13 C isotopes, providing detailed structural data through molecular vibrations . High-Performance Liquid Chromatography (HPLC) is an advanced technique that improves upon traditional column chromatography by enhancing separation speed, resolution, accuracy, and sensitivity. HPLC offers benefits like small sample size, customizable tests, and precise data generation, making it a valuable tool in pharmaceutical analysis. Spectrofluorimetry, the most sensitive method, can detect substances at the femtogram level, unlike other methods that require microgram-level sample preparation . Section title: Introduction Educational score: 4.147913455963135 Domain: biomedical Document type: Review Language: en This review differs from existing ones by providing a detailed exploration of the synthesis, surface functionalization, and photoluminescent properties of carbon dots (CDs), with a particular emphasis on their emerging applications in photocatalysis, energy, and sensing. Unlike other reviews, we focus on the potential of CDs as safer alternatives to conventional fluorescent compounds, particularly in in-vivo analysis. The specific aims of this review are to offer a comprehensive overview of recent advancements in CDs, highlighting their diverse applications and exploring their potential as substitutes for toxic compounds, as well as their role in electron storage and transport when exposed to light. Furthermore, this review addresses key gaps in the current literature, including the need for alternative materials that can efficiently remove unfiltered contaminants in wastewater treatment and the underutilized potential of CDs in nanomaterial-based solutions. By examining these aspects, we aim to uncover new avenues for the application of CDs in both biotechnological and environmental fields. Section title: Introduction Educational score: 4.027393817901611 Domain: biomedical Document type: Review Language: en Based on the recent advancements in the field of CDs, this review hypothesizes that CDs, due to their unique photoluminescent properties, surface functionalization, and environmental compatibility, can serve as safer and more efficient alternatives to traditional fluorescent compounds in various applications, including sensing, photocatalysis, and environmental monitoring. Furthermore, it is hypothesized that CDs have the potential to overcome the limitations of conventional wastewater treatment systems by offering innovative solutions for contaminant removal, thus providing significant benefits in both biotechnological and environmental fields. Section title: Nanomaterials in sensing of pharmaceuticals Educational score: 4.051898002624512 Domain: biomedical Document type: Review Language: en Nanomaterials are materials that have at least one dimension in the nanometer (nm) range and range in size from approximately 1 to 100 nm . According to the literature, most drug identification methods are based on chromatographic techniques. These techniques are well-established and accepted by regulatory authorities. However, it has several drawbacks related to relatively high cost, analysis time, and pretreatment steps . The incorporation of nanomaterials has enabled the development of novel and effective sensor platforms . The use of nanomaterials for biosensor development has attracted a lot of interest, and carbon nanomaterials (CNMs) are at the forefront. CNMs are composed of sp 2 -bonded graphitic carbon and are mainly classified into fullerenes (0-dimensional), carbon nanotubes (CNTs) (1-dimensional), and graphene (2-dimensional) . CNMs offer superior electrical conductivity, chemical stability, biocompatibility, and strong mechanical strength because of special characteristics including surface-to-volume ratio . Section title: Nanomaterials in sensing of pharmaceuticals Educational score: 4.3796892166137695 Domain: biomedical Document type: Review Language: en As anticipated, these characteristics can affect the stability and selectivity of nanomaterials, as can the capacity to form hydrogen bonds, stacking, dispersion forces, dative bonds, and hydrophobic interactions . A quick search of the Web of Science database over the past five years for the terms “fullerenes,” “CNTs,” and “graphene” yields over 12,000, 32,000, and 98,000 papers, respectively . The facile functionalization and modification of such nanomaterial-based biosensors facilitated improved efficiency in the detection of antibiotic residues and narrow therapeutic index (NTI) drugs . Additionally, nanoparticles (NPs) can be used for targeted drug delivery and high drug-loading capacities . They also show great potential in cancer therapy by improving drug performance, reducing systemic side effects, and increasing therapeutic efficacy . However, there are complexities, difficult and lengthy synthetic processes, and the toxicity of heavy metal quantum dots (QDs) may hinder their application in biosensing . Therefore, nanomaterials can be used to determine drugs . However, some of them are toxic to humans. A common mechanism by which metal oxide NPs cause toxicity is a combination of the NPs properties and their propensity to generate reactive oxygen species [ROS] and cause toxicity in cells, genes, and neurons. Section title: Carbon dots (CDs) Educational score: 4.512267112731934 Domain: biomedical Document type: Review Language: en Quasi-spherical particles having a diameter of less than 10 nm, known as fluorescent CDs were first identified in 2004 . CDs are a new class of nanostructures made of carbon (C) that have intriguing characteristics and small sizes. Surface-functionalized carbonaceous NPs known as CDs have extraordinary properties, including adjustable FL . CDs were reported to have good biocompatibility, less toxicity , high photoluminescence (PL) intensity , high chemical stability , and possess excellent biological, physical, and chemical properties, thus having great potential in various applications . Only a few of the benefits associated with their luminescence are their outstanding water solubility, biocompatibility, non-toxicity, high sensitivity to the environment, and apparent electron-donating and receiving capacities . CDs exhibit appealing optical characteristics such as size-dependent PL , photo-induced electron transfer (PET), up-conversion luminescence, chemiluminescence, and electrochemiluminescence (ECL) . These dots possess an inner sp 2 and outer sp 3 hybridized structure that frequently contains oxygen-containing functional groups. The surface of CDs imparts several traits to them, including effortless electron transfer, which can confer anti- or pro-oxidant behavior . Section title: Carbon dots (CDs) Educational score: 4.275086879730225 Domain: biomedical Document type: Study Language: en In addition, CDs can be easily functionalized with hydroxyl, carboxyl, carbonyl, amino, and epoxy groups on their surfaces. This additional advantage enables them to bind readily with both inorganic and organic moieties. The functional groups present on the surfaces of CDs allow them to adopt either hydrophilic or hydrophobic properties, providing the necessary thermodynamic stability in different solvents, particularly in water . Moreover, CDs have exceptional sensing properties like multiplex, selective, and specific detectability. Abundant functional groups (such as amine, carboxyl, hydroxyl, etc.) or polymer chains on the surface of CDs make them highly soluble in aqueous solutions and easily functionalized with other nanomaterials . Because of their extremely sensitive responses to target molecules and tunable surface functional groups, these characteristics make CDs particularly appealing in sensing applications. Another fascinating property of CDs is their tunable emission, characterised by multiple FL colors under various excitation wavelengths . Section title: Properties of CDs Educational score: 4.743282318115234 Domain: biomedical Document type: Study Language: en Without a crystal structure, CDs are always spherical and split into carbon NPs. All CDs have linked or altered chemical groups, like chains made of oxygen, amino acids, polymer etc., on their surfaces. X-ray diffraction (XRD), Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM) are the direct characterization techniques for the carbon core XRD. NMR, X-ray photoelectron spectroscopy (XPS), Fourier transforms infrared (FTIR), and matrix-assisted laser desorption ionisation time-of-flight (MALDI-TOF) are used to assess the grafting of chemical groups. These luminous CDs are therefore not made of “pure” C compounds. Various properties of CDs are depicted in Fig. 2 . The PL behavior of these CDs is mostly determined by the hybridization and coupling between the C core and surrounding chemical groups . In the UV spectral region, CDs typically exhibit considerable absorption with an extension into the visible spectrum. Sometimes, at a wavelength that is significantly longer than the UV absorption peak, a shoulder or a weak peak is also seen. Longer wavelength UV absorption, which typically takes the form of a shoulder or a weaker peak between 300 nm and 400 nm, is attributed to n → π∗ transitions of C=O. Shorter wavelength UV absorption, which is roughly between 200 nm and 350 nm, is attributed to π → π∗ electronic transitions of C=C and C=N . The UV–Vis spectra of Yellow-Green CDs (YG-CDs) give several absorption bands at 270 nm and 382 nm, just like Blue-CDs (B-CDs) do. However, YG-CDs have a higher absorption intensity than B-CDs, which may be due to the latter's higher degree of carbonization in a more acidic hydrothermal environment . The PL emission, comprising excitation-dependent and excitation-independent PL, which is caused by core-related and surface state-related emissions, is one of the CDs most fascinating characteristics . Further remarkable FL characteristics of CDs include tunable PL emission, excitation wavelength-dependent PL emission, strong FL stability, and effective photobleaching resistance. Some CDs can have up-conversion PL (UCPL) emission characteristics, which means that the emission wavelengths of carbon quantum dots (CQDs) are shorter than their excitation wavelengths, in contrast to standard PL emission. The most common explanations for the up-conversion FL phenomenon are often two-photon excitation and anti-Stokes PL emissions . CDs exhibit ECL capabilities and are useful for metal ions detection, optical devices, and biosensors . CDs have a protracted, intense FL emission (up to a year). As CDs can withstand a wide pH range (from 3 to 12), they exhibit excellent photobleaching impedance. Excitation following direct oxidation, amplification, or inhibition of luminescence are all ways that CDs might produce chemiluminescence . Fig. 2 Properties of CDs. Fig. 2 Section title: Synthesis of CDs Educational score: 4.09539794921875 Domain: biomedical Document type: Study Language: en There are currently many different synthetic approaches that can be used to make CDs. The majority of studies focus on easy, affordable, size-controllable, or large-scale synthetic ways to produce CDs of superior quality. Chemical and physical processes are used to create synthetic materials, respectively, depending on the characteristics of the transformations of C sources to final products. Moreover, two classes of top-down and bottom-up may characterise existing synthetic techniques when taking into account the link between the sources and products . The synthesis process may also require additional purification of the end products using techniques like centrifugation, electrophoresis, dialysis, etc. One study by Zhu et al., for instance, used three cycles of concentration/dilution to separate CDs from other reactants . For this class, CDs are produced through oxidation, laser ablation, arc discharge, and electrochemical release on somewhat macroscopic C structures including CNTs, graphite columns, graphene, suspended C powders, etc . In bottom-up processes, CDs are made from a variety of small molecule precursors; most of them enable the manufacture of functionalized CDs in a single step. It consists of pyrolysis, microwave synthesis, ultrasound-assisted synthesis, and hydrothermal synthesis . Several C sources are utilized, including amino acids, citric acid, sugar, and even food waste. Fig. 3 Schematic diagram showing various sources and methods for synthesis of CDs. Fig. 3 Section title: Top-down methods Educational score: 4.421211242675781 Domain: biomedical Document type: Study Language: en Chemical oxidation frequently involves oxidising the substrate with an oxidative reagent. Chemical oxidation is also a quick and efficient approach to large-scale production. Coal, wood, and coconut activated carbons-all readily available in the marketplace-were the C sources. Nitric acid made it simple to etch CDs out of the amorphous structure of activated carbons. Chemicals with amine ends were then used to carry out the passivation process. The three C sources' end products had a constrained size distribution and spectacular luminosity [ , , ]. Because a huge volume of fluorescent CDs can be created in a short period, the laser ablation including solid targets in liquid (LASL) approach for producing fluorescent CDs can be very rapid and efficient. For the synthesis of high-quality or smaller-sized nanostructures, other synthesis procedures, that include the ablation of suspended micro particles or powders, need a longer ablation period. In this technology, greater control of the size distribution can be achieved by carefully controlling heat dissipation via wavelength and intensity change. In comparison to microscale-ablated particles, the size of the emitting NPs generated in the study is in the nanoscale range . Top-down electric arc or arc-discharge synthesis was used to create the first luminous CDs. In order to extract fluorescent C from raw small wall nanotubes (SWNTs), soot, and other materials using a preparative electrophoretic method, it was shown that the fluorescent materials PL quantum yield (PLQY) could reach 1.6 percent at 366 nm excitation wavelength. The benefit of this approach is that the CDs may emit multiple fluorescent colors under UV light without undergoing any surface alteration, and it just needs a simple purification procedure. It is also portable and environmentally friendly. The formation of mixes, low yield, difficulties in surface and compositional modification, and difficulty in these alterations are also drawbacks . A C material, such as graphite, CNTs, or C fibre electrodes, is chemically cut using the electrochemical method, which is influenced by an electric field. The method's low cost and simplicity make it useful. Interestingly, by altering process variables like the temperature, electric field, CNT diameter, and concentration of the supporting electrolyte, CDs made electrochemically can have their sizes adjusted . Section title: Bottom-up methods Educational score: 4.199028968811035 Domain: biomedical Document type: Study Language: en A simple bottom-up hydrothermal approach has been reported to make CDs. The colorless solution first needs to close in a Teflon-coated stainless-steel autoclave and then be kept at a definite temperature for a particular time. The autoclave was left to naturally cool to room temperature following the reaction. The solution is either centrifuged or passed through dialysis tubing of a certain molecular weight to remove the precipitation and to eliminate leftover small molecules, the CDs were dialyzed against ultrapure water at room temperature using a membrane . Depending on the frequency and strength of the applied field, ultrasound is a typical laboratory instrument that can be used to emulsify mixtures, drive chemical processes, and nebulize liquids into fine mists . Microwaves are electromagnetic wave types with a broad wavelength range of 1 mm (mm) to 1 m (m) that are frequently employed in daily life and science. The microwave can also deliver high energy to break the chemical bonds in the substrate, just like a laser can. The synthesis of CDs is thought to be more energy-efficient when done in a microwave, and the reaction time can also be significantly reduced. The substrate is typically pyrolyzed and surface functionalized during microwave-assisted synthesis . Section title: CDs as a sensor Educational score: 3.6689891815185547 Domain: biomedical Document type: Study Language: en The sensing mechanism of the CDs depends upon the chemical bonding of the fluorescent probe. Various mechanisms of CDs have been available for sensing the analyte, these include Förster resonance energy transfer (FRET) , inner filter effect (IFE) , photoinduced electron transfer (PET) , intramolecular charge transfer (ICT) , static quenching (SQ), dynamic quenching (DQ) , aggregation caused quenching (ACQ), aggregation-induced emission (AIE) . Fig. 4 The sensing mechanism of CDs. Fig. 4 Section title: Different mechanisms of CD Educational score: 2.6909339427948 Domain: biomedical Document type: Other Language: en The FL behavior of CDs is governed by various mechanisms that influence their emission properties and sensing capabilities. These mechanisms include FRET, IFE, SQ and DQ, PET, ICT, as well as phenomena like ACQ and AIE. Section title: Förster resonance energy transfer (FRET) Educational score: 4.288532733917236 Domain: biomedical Document type: Study Language: en In FRET, energy is transferred non-radiatively from an excited donor molecule (D), typically a fluorophore, to a close-by ground-state acceptor molecule (A) via long-range dipole-dipole interactions. For efficient FRET, the acceptor must absorb energy at the donor's emission wavelength (s), though it does not need to emit this energy fluorescently. The efficiency of FRET is significantly influenced by three main factors: the degree of spectral overlap between the donor's emission and the acceptor's absorption, the relative orientation of the transition dipoles, and most importantly, the distance between D and A, usually in the range of 10–100 Å (Å), which is comparable to the size of many biological macromolecules . Section title: Inner filter effect (IFE) Educational score: 4.081966400146484 Domain: biomedical Document type: Study Language: en The IFE involves an absorber in a sensor system that modulates the excitation or emission of light from a fluorescent molecule. In an IFE-based sensing system, both an absorber and a fluorescent molecule must coexist. The absorber's absorption spectrum overlaps with the excitation and/or emission spectra of the fluorophore. This overlap enables the absorber to control and influence the FL emission. The system requires the absorber to exhibit a selective response to the analyte concentration, while the FL intensity of the fluorophore remains unaffected by the analyte, ensuring its role as an indicator in the sensor system . Section title: Photoinduced electron transfer (PET) Educational score: 4.226491928100586 Domain: biomedical Document type: Study Language: en PET is a mechanism in which a fluorophore is linked to a recognition receptor via a spacer. FL quenching in PET occurs due to intramolecular electron transfer between the receptor and the fluorophore. Two types of PET processes are recognized: (1) Acceptor-PET (A-PET): Electron transfer from the receptor to the fluorophore occurs when the receptor's Highest Occupied Molecular Orbital (HOMO) energy level is higher than that of the fluorophore. (2) Donor-PET (D-PET): Electron transfer from the excited fluorophore to the receptor's Lowest Unoccupied Molecular Orbital (LUMO) level occurs during D-PET. The PET process is inhibited when the receptor binds to a target analyte, leading to restored FL emission . Section title: Intramolecular charge transfer (ICT) Educational score: 4.211217403411865 Domain: biomedical Document type: Study Language: en ICT involves electron transfer from a donor (D) to an acceptor (A) within a fluorescent probe upon light stimulation. When the donor interacts with an analyte, its electron-donating ability decreases, increasing the HOMO-LUMO energy gap and causing a blue shift in FL emission. Conversely, the interaction of the acceptor with the analyte decreases the energy gap, resulting in a red shift. Thus, both FL intensity and emission wavelength can be used for analyte detection. The varying dipole moments between the ground and excited states of ICT probes make them sensitive to different solvent environments, making them ideal for detecting changes in solvent conditions . Section title: Static quenching (SQ) Educational score: 3.5368432998657227 Domain: biomedical Document type: Other Language: en SQ occurs when a non-fluorescent ground-state complex forms between the quencher and the CDs. This complex reduces the FL intensity of the CDs and alters their absorption spectrum. Temperature increases can destabilize this ground-state complex, reducing the quenching effect. Section title: Dynamic quenching (DQ) Educational score: 4.090999126434326 Domain: biomedical Document type: Study Language: en DQ involves the interaction between an excited-state fluorophore and a quencher, resulting in energy or charge exchange that returns the fluorophore to its ground state. Unlike SQ, DQ affects only the excited state and does not alter the absorption spectrum of the fluorophore. The FL lifetime of the fluorophore is reduced in the presence of a quencher. Higher temperatures typically enhance the DQ effect, increasing the rate of quenching interactions . Section title: Dynamic quenching (DQ) Educational score: 4.155179023742676 Domain: biomedical Document type: Study Language: en The reduction in FL intensity due to quenching can be quantified using the Stern-Volmer equation: F 0 /F = 1 + K[Q] = 1 + k q τ 0 [Q] Where K is the Stern-Volmer quenching constant, [Q] is the quencher concentration, τ 0 is unquenched lifespan, and k q is the bimolecular quenching constant, and F and F 0 are FL intensities in the presence and absence of the quencher, respectively. Section title: Aggregation-caused quenching (ACQ) and aggregation-induced emission (AIE) Educational score: 4.206335067749023 Domain: biomedical Document type: Study Language: en In ACQ high concentrations or solid-state fluorophores often exhibit diminished FL due to self-quenching. This effect arises from interactions such as hydrophobic effects, stacking, and hydrogen bonding, leading to non-radiative decay pathways. In contrast to ACQ, AIE materials show enhanced FL in high concentrations or solid forms. In dilute solutions, non-radiative energy dissipation occurs via intramolecular rotation. However, in the aggregated state, this rotation is restricted, leading to suppressed non-radiative decay, and enhanced FL emission organization groups similar principles together, improving the clarity and logical flow of the discussion on various FL mechanisms associated with CDs . Section title: Modification of CDs Educational score: 4.431922435760498 Domain: biomedical Document type: Study Language: en Doped-CDs are carbogenic NPs with an average size of less than 10 nm that have atomic impurities added like nitrogen (N), sulfur (S), phosphorus (P), boron (B), etc. during the production process to enhance their optical, electrical, and chemical capabilities. One can distinguish between single- and multiple-doped CDs based on how many atomic impurities have been added to the structure of the CDs. One of the most well-known options is N since it has five valence electrons, a similar atomic size to C, and can form bonds with C atoms. When the N content in the CDs rises, the FL peak has shown that it will move to a longer wavelength under the same stimulation. The observation's justification is based on the N-doped material forming new FL origins. In other research, N is also seen to improve the efficacy of emissions as opposed to displacing them. The mechanism is thought to involve electrons in the conduction band and the occurrence of an upward shift in the Fermi level. Hence, various polymers used as a precursor material for C and N sources are dodecyl-grafted-poly(isobutylene-alt-maleic-anhydride) , hydrosoluble chitosan , dried shrimp shells , citric acid, and urea , dried prawn shell , oolong tea , monkey grass , folic acid (FA) and phosphoric acid (H 3 PO 4 ) , lysine and ortho-phosphoric acid , p-phenylenediamines and ammonia water , gum ghatti and ethylenediamine , Borassus flabellifer (B. flabellifer) and aq. Ammonia , m-phenylenediamine , Ru(bpy)2(phen-NH 2 ) , 4-aminophenol , ethylenediamine, and Kentucky bluegrass , β-resorcylic acid and ethylenediamine , black soya beans , glucosamine and ethylenediamine , citric acid and diethylenetriamine , highland barley as C source and ethanediamine as N resource , biomass bacterial cellulose , tartaric acid and urea , adenosine , dried chrysanthemum buds, and ethylenediamine . The band-gap energy of photoexcited electrons may be modified by the S atom's density of states or emissive trap states, giving functionalized CDs additional favorable properties [ , , , , , , , , , ], sodium citrate solution, and sodium thiosulfate , blackstrap molasses, H 2 O 2 , and garlic powder , mercaptosuccinic acid , sulphuric acid (H 2 SO 4 ) . Fig. 5 Doped CDs sources. Fig. 5 Fig. 6 Single, multi, and co-doped CDs. Fig. 6 Section title: Modification of CDs Educational score: 4.039722442626953 Domain: biomedical Document type: Study Language: en Thus various polymers used as precursor material for C and S sources are sodium thiosulfate and sodium citrate . With only three valence electrons, B (one less than C). As a result, adding a B atom to a C cluster causes the generation of p-type carriers inside CDs, altering their electrical structures and optical characteristics [ , , , , ]. Thus various polymers used as precursor material for C and B sources are phenylboronic acid , boric acid, urea and citric acid , glucose and boric acid , L-ascorbic acid and boric acid , citric acid, H 2 SO 4 , ammonia water, boric acid, and isopropyl alcohol , boric acid and ethylenediamine , citric acid monohydrate, thiourea, and boric acid . Moreover, citric acid, rhodamine B, methylene blue,1, 2-diboranyethane, N, N-dimethylformamide (DMF, anhydrous, 99.8 %) , etc. The P atom can have a significant impact on the chemical and electrical structures of semiconductors since it is a major electron donor in semiconductors, which are endowed with promising uses in photovoltaic devices and catalysts. The bigger size of the P atom compared to the C atom directly contributes to an increase in disorders inside the P-doped graphite carbon backbone [ , , , ]. Section title: Modification of CDs Educational score: 3.7164995670318604 Domain: biomedical Document type: Review Language: en The various polymers used as precursor materials for C and P sources are L-threonine and phosphorous pentoxide , sucrose and H 3 PO 4 , dextrose and disodium phosphate (Na 2 HPO 4 ) , beta-cyclodextrin and sodium pyrophosphate , lactose, and concentrated H 3 PO 4 , orthophosphoric acid and glucose . Nitrogen, Sulfur co-doped carbon dots (N, S-CDs), one of the heteroatom-containing CDs, display their remarkable FL behaviors . Example: thiourea and glutathione , p -aminobenzenesulfonic acid , DL-malic acid, ethanolamine and ethane-sulfonic acid , citric acid and L-cysteine , ammonium persulfate, glucose, and ethylenediamine , citric acid and thiourea , sodium citrate and thiourea , methionine and citric acid , basic fuchsin and sulfosalicylic acid , 4-aminophenylboronic acid hydrochloride and 2, 5-diaminobenzenesulfonic acid , ethylenediamine, L-cysteine and malic acid , citric acid and dithiooxamide , garlic , citric acid monohydrate and cysteamine , urea and H 2 SO 4 , citric acid and thiosemicarbazide , trisodium citrate dehydrate and L-cysteine , H 2 SO 4 , methionine and acrylic acid , polyvinylpyrrolidone and poly(4-styrenesulphonic acid) sodium salt , citric acid and arginine (A), histidine (H), lysine (L), cysteine (C), and methionine (M) . In addition, other combination includes heating egg white, egg yolk, pigeon feathers or pigeon manure , garlic and alfalfa , thiomalic acid and diethylenetriamine , rose petals, ethylenediamine, L-cysteine , para-benzoquinone and L-cysteine , cigarette and H 2 SO 4 , thioctic acid and triethylene tetramine . Section title: Modification of CDs Educational score: 4.221870422363281 Domain: biomedical Document type: Review Language: en Heteroatoms like N and B have been created to enhance the optical performance of CDs. The luminous characteristics of these CDs are fascinating, including temperature- and pH-dependent FL responses and excellent quantum yield . Solanum betaceum ( S. betaceum ) fruit extract , trisodium citrate, urea, and boric acid , adenine and aminobenzene boronic acid monohydrate , citric acid, boric acid and ethylenediamine , 2,5-diaminobenzenesulfonic acid and 4-aminophenyl boronic acid , petroleum coke , 3-aminophenylboronic acid , citric acid, boric acid, and tris base , citric acid, urea, and boric acid, etc. are the various precursors used for the synthesis of N, B -doped CDs . On the periodic table, N and P sit next to C and serve as important tracking elements in the field of biomedical imaging. These two components change the optical and electronic characteristics of CDs and advance our fundamental knowledge of their PLQY. Moreover, this may result in multifunctional applications in photothermal therapy (PTT) and photoimaging. Some precursors used for the synthesis of N, P-doped CDs are ethylenediamine and N-phosphonomethylaminodiacetic acid , 1,4-naphthalenedicarboxylic acid and urea , glucose, ammonia, and H 3 PO 4 , adenosine 5′-mono phosphoric acid disodium salt dehydrate , diethylenetriaminepenta and m-phenylenediamine , glucose, polyethyleneimine and H 3 PO 4 , phytic acid and L-arginine , 1,2-ethylenediamine, phthalic acid and H 3 PO 4 , lily bulb , citric acid, tris (2-aminoethyl) amine and orthophosphoric acid , sodium citrate and diammonium phosphate , maize and urea , alendronate sodium , polyethylene glycol (PEG) (C source), and H 3 PO 4 . Various sources used for the synthesis of N, Cl-doped CDs are o-phenylenediamine, hydrochloric acid (HCl) and selenourea , cetylpyridinium chloride , 4-chloro-1,2-diaminobenzene and dopamine , p-phenylenediamine, melem hydrazine, and aluminum chloride hexahydrate , glycerine, choline chloride and urea , chloranil and triethylenetetramine , glucose, concentrated HCl and 1,2-ethylenediamine . B, N, and S-doped were synthesized by 2, 5- diaminobenzene sulfonic acid, and 4- aminophenyl boronic acid hydrochloride . The N, S, P, and Cl-doped were synthesized by glucose and ethylenediamine, and then H 2 SO 4, concentrated H 3 PO 4 , and concentrated HCl were added orderly into the beaker to get the CDs . Section title: Applications of fluorescent CDs based sensors for pharmaceuticals Educational score: 4.3606767654418945 Domain: biomedical Document type: Study Language: en As CDs are reported best for sensing pharmaceuticals. Fig. 13 illustrates a variety of CDs applications along with drug identification in pharmaceuticals. So far, some of the drugs listed in Table 1 are detected by carbon nanodots (CNDs) through a different mechanism of CDs. The study investigated the impact of deoxygenation and radical scavengers on the FL intensity of the C-dots-Ni(IV) system. It was proposed that when Ni(IV) reacts with dissolved oxygen in an alkaline solution, it produces the superoxide radical (•O 2 − ). Both Ni(IV) and •O 2 − can interact with C-dots, generating C-dot• + and C-dot• − , which then undergo electron transfer annihilation, forming an excited-state C-dot∗ as the final emitter. The target analyte was found to inhibit chemiluminescence by competitively reacting with Ni(IV). This led to the development of a flow-injection chemiluminescence method, which proved to be a fast, simple, sensitive, and robust technique for detecting trace levels of reducing compounds . In a separate experiment, CDs were synthesized using sodium citrate and ammonium bicarbonate through a hydrothermal process. The FL intensity of the CDs was found to be pH-dependent, increasing with pH up to 6.0, before stabilizing between pH 7.3 and 7.7. The study also tested the effects of various interfering substances, revealing that D-penicillamine (D-PA) caused significant quenching of the FL, while increasing concentrations of Hg 2+ also reduced the FL intensity, with near-total quenching occurring at 4 × 10⁻⁵ mol L⁻ 1 of Hg 2+ . Table 1 Pharmaceutical applications of fluorescent CDs-based sensors. Table 1 Sr. No. Drug name Wavelength excitation(λ ex ) Wavelength emission(λ em ) Linearity range Mechanism Ref 1. Paracetamol 360 nm 445 nm 4.48x10 −7 -8.96 x10 −5 μM Ni(IV) reacted with CDs produced could form an excited state C-dot∗ which interacts with the target analyte due to its competitive reaction with Ni(IV). 2. D-penicillamine 358 nm 442 nm 2–24 μmol/L Fluorescent switch sensor 3. Kaempferol 370 nm 490 nm 3.5–4.9 μM Non-radiative energy transfer (FRET) 4. Amantadine 335 nm 446 nm – FRET 5. Chloramphenicol 400 nm 525 nm – FRET 6. Hyperin 300 nm 540 nm 0.22–55 μM Non-radiative energy transfer 7. Sumatriptan 380 nm 446 nm 1–20 μM The fluorescent quenching observed is caused by the formation of hydrogen bonds between the nitro groups of DNB-CDs and the aliphatic -NH group on the phenyl aromatic ring of SUM. 8. 6-Mercaptopurine 370 nm 445 nm and 565 nm 1.0–100.0 μmol L −1 FRET 9. Gentamicin 340 nm 385 nm 0 to 2.9 × 10 −4 mol/L FRET 10. Gentamicin and kanamycin 390 nm 482 nm 200–2000 nM FRET 11. α-glucosidase 410 nm 510 nm 100 μL IFE 12. Iron 370 nm 432 nm 0–1.5 mM IFE 13. Hematin 314 nm 362 nm 0–75 μM IFE 14. Cefixime 350 nm 455 nm 0.2 × 10 −6 M to 8 × 10 −6 M IFE 15. Tetracycline 345 nm 435 nm 0.5–25 μM IFE 16. Chlortetracycline 370 nm 447 nm 0.4–20 μg/mL IFE 17. Tetracycline 350 nm 420 nm 0–50 μM IFE 18. Tetracycline 370 nm 440 nm 0.5–60 μM Internal filtering effect 19. Tetracycline 360 nm 440 nm 0.1–4.0 μg mL −1 IFE 20. Tetracycline and oxytetracycline and chlortetracycline 381 nm 456 nm TC (1–60 μM), OTC (1–40 μM) and CTC (1–80 μM) IFE 21. Nimesulide 330 nm 408 nm 0–100 μM IFE 22. Curcumin 380 nm 467 nm 0.1–35 μM IFE 23. Clioquinol 360 nm 440 nm 40.0–400.0 μmol L −1 IFE 24. Berberine hydrochloride 370 nm 452 nm 0.5–30.0 μmol/L IFE 25. Diacerein 325 nm 412 nm 2.5–17.5 μg/mL IFE 26. Captopril 520–550 nm – 1–50 μM IFE 27. Daunorubicin and doxorubicin – 450 nm DAN DOX IFE 28. Mitoxantrone 560 nm 655 nm 0.096–30 μM IFE 29. Gefitinib 320 nm 410 nm 0.1–20 μg/mL IFE 30. Doxorubicin 491 nm 591 nm 1–30 μM IFE 31. Nitazoxanide 340 nm 418 nm 0.25–50.0 μM IFE 32. Myricetin 360 nm 436 nm 0.2–112 μM IFE 33. Levocetirizine and niflumic acid 319 nm 392 nm (levocetirizine − 1.0–100 μM and niflumic acid − 0.5–100 μM) IFE 34. Vitamin B 12 545 nm 595 nm 1–65 μM/70–140 μM Internal filtration effect 35. Metronidazole 350 nm 425 nm 0.5–22 μM PET 36. Thiamine 367 nm 430 nm 10–50 μM Quenching due to Cu 2+ ion and regain after addition of thiamine. (Turn on) 37. Cephalosporin 300 nm 689 nm 0.2–80 μmol/L IFE 38. Prilocaine 400 nm 485 nm 2.3–400 nmol L −1 Quenching assay/Turn off the sensor 39. Enrofloxacin 368 nm 452 nm 1–15 μg/mL The FL was suppressed by Cu 2+ ions and then restored by the addition of ENR, resulting in an off-on switch of the FL. 40. Chlortetracycline 360 nm 438 nm 1–70 μM The FL of CDs is quenched by the addition of QDs, while increases linearly with the concentration of CTC resulting in an turn off–on switch of the FL 41. Glutathione 360 nm 430 nm 20–400 μM The FL of CDs was quenched with the addition of Cu 2+ , by the formation of CDs-Cu 2+ and recovered rapidly with the addition of GSH, due to the stronger interaction between GSH and CDs-Cu 2+ , resulting in an turn off–on switch of the FL. 42. Pentachlorophenol (PCP) 360 nm 440 nm 10–300 μM The FL of NS-CDs was significantly quenched by the addition of H 2 O 2 and HRP and induced FL quenching. While after the addition of PCP provided a reducing environment that can protect the active group of NS-CDs from oxidation. Thus, resulting in an turn off–on switch of the FL. 43. Ampicillin 340 nm 427 nm 6.6–200 ppm Fluorescent quenching 44. Nitrofurantoin 340 nm 470 nm 0–500 μM IFE and SQ 45. Phenobarbital 340 nm 410 nm 0.4–34.5 nmol L −1 Fluorescent quenching 46. Clonazepam 340 nm 430 nm 5x10 −8 x10 −6 M Fluorescent quenching 47. Acetaminophen 350 nm – 1–80 μM Fluorescent quenching 48. Atorvastatin 290 nm 423 nm 0.025–50 μM SQ 49. Doxorubicin 360 nm 441 nm 0.5–6.5 μM SQ 50. Imatinib 345 nm 415 nm 1.0–15.0 mg/mL SQ 51. Curcumin 360 nm 440 nm 0.339–136.0 μM SQ 52. Tetracycline 330 nm 520 nm 0–27.27 μM SQ 53. Folic acid 360 nm 450 nm 10–100 μg/mL DQ 54. Isoniazid 270 nm 447 nm 4–140 μM IFE and SQ 55. Quercetin 350 nm 450 nm 0.003–80 μmol/L IFE and SQ 56. Tigecycline 365 nm 500 nm 0.005–20 μg/mL IFE and SQ 57. Tetracycline 360 nm 520 nm 0.5–40 μM IFE and DQ 58. Nitrotyrosine 420 nm 679 nm 20–105 μM SQ and DQ 59. p-benzoquinone 350 nm – 0–25 mmol/L DQ 60. Methotrexate 355 nm 450 nm 0–50 μg/mL Fluorescent quenching 61. Doxorubicin 350 nm – 0.5–25 μg/mL Fluorescent quenching 62. Chondroitin sulfate 488 nm 520 nm 0.05–2 μg/mL Electrostatic interaction 63. Flutamide – – 0.05–590 μM – 64. Cytochrome C 475 nm 530 nm 0.5–25 μM IFE 65. Zoledronic acid 340 nm 430 nm 0.1–10 μM ZA could not quench the FL intensity of the N-CDs without Fe 3+ , once ZA was added to the N-CDs-Fe 3+ system, the formation of a complex between ZA and Fe 3+ ions occurred and the FL of N-CDs becomes on. (Turn on) 66. Glucose 520 nm 582 nm 0.5–1500 μM SQ Section title: FRET-based detection mechanism Educational score: 4.517726898193359 Domain: biomedical Document type: Study Language: en The CDs were synthesized by adding distilled deionized water to diphosphorus pentoxide (P 2 O 5 ) in glacial acetic acid, conducted in a fume hood. After cooling, a dark brown solid was obtained. The FL intensity of the CDs was pH-dependent, peaking at pH 6.0 before decreasing with higher pH levels. The CDs showed high selectivity for kaempferol (KAE), which significantly quenched their FL in the presence of other substances, indicating strong sensitivity towards KAE . A method was developed to produce polyethyleneimine (PEI)-functionalized blue emissive CDs (b-CDs) using citric acid and PEI via a one-step hydrothermal process. These b-CDs were used to create a fluorescent immunoassay for simultaneously detecting chloramphenicol (CAP) and amantadine (AMD) in skinless chicken breasts. The b-CDs, along with green emissive CDs (g-CDs), featured numerous amino groups and distinct FL emission peaks. The study employed haptens of CAP and AMD as energy donors in a FRET system. Two-dimensional WS2 nanosheets (NSs) were used as energy acceptors, modified with antibodies specific to CAP and AMD. This selective antigen-antibody interaction facilitated the attachment of hapten-functionalized CDs to the WS2 NSs, resulting in FL quenching due to FRET. The immunoassay demonstrated potential for rapid detection of drug residues in food . The CDs were synthesized using a self-catalysis method, with FL intensity decreasing rapidly in the first minute and stabilizing after 10 min, which was chosen for further experiments. The study assessed the impact of interfering substances like metal ions, biomolecules, and co-existing compounds, testing the method's effectiveness for real sample analysis. The results showed that the CDs were highly selective for hyperin (Hyp), with only slight changes in FL intensity at low concentrations and a significant decrease as Hyp concentration increased. The method was successfully applied to quantify Hyp in real samples, including fufangmuji granules and human serum . The researchers developed a selective and sensitive fluorescent probe using zein biopolymer, functionalized with 3,5-dinitrobenzoyl chloride (DNB) to create DNB-CDs for detecting sumatriptan (SUM). The DNB-CDs were synthesized via direct pyrolysis of zein without additional reagents. Using the standard addition method for analysis, the DNB-CDs showed a strong selective response to SUM, unaffected by potential interfering substances. The study suggests that these CDs can be effectively used for determining SUM levels in human samples . A one-step aqueous synthesis method was used to create Zn-doped CdTe quantum dots (ZnCdTe QDs), which were combined with B-CDs to develop a ratiometric fluorescent probe for detecting 6-mercaptopurine (6-MP). The probe exhibited different FL responses from the yellow emission of ZnCdTe QDs and the blue emission of CDs when exposed to 6-MP. After adding 6-MP, the FL intensity ratio remained stable for up to 20 min, with the probe showing the strongest response at pH 8.7. Using FRET, the FL of ZnCdTe QDs was selectively quenched, while the FL of CDs remained unaffected. The probe successfully detected 6-MP in human serum, offering a rapid method for 6-MP analysis in biological samples. Fig. 7 presents a schematic illustration of ratiometric FL sensing for 6-MP . Fig. 7 Schematic illustration of ratiometric fluorescence sensing for 6-MP. Fig. 7 Section title: FRET-based detection mechanism Educational score: 4.236636161804199 Domain: biomedical Document type: Study Language: en The researchers developed a sensor using N-C quantum dots (QDs) by combining a CQDs solution with sodium hydroxide, dried wheat straw powder, 2,2,6,6-tetramethylpiperidine amine, and 4,5-imidazole dicarboxylic acid. The FL intensity of the N-CQDs increased gradually at pH 7 as the gentamicin (GEN) concentration increased. The sensor's selectivity for GEN was evaluated using GEN analogs and metal ions, with metal ions causing only a slight decrease in FL intensity (around 5 %). This detection method was proven effective for accurately detecting GEN in water samples, offering a fast and simple approach with significant potential for detecting GEN residues in aqueous solutions . A unique two-in-one sensor based on Au@CQDs nanocomposites (NCs) was developed for detecting gentamicin (GENTA) and kanamycin (KMC). In the synthesis, CQDs acted as reducing agents to create Au@CQDs NCs. Initially, the FL intensity of CQDs decreased due to energy transfer after the formation of Au@CQDs NCs. However, the FL intensity recovered in the presence of the antibiotics, indicating that the sensor could effectively detect both GENTA and KMC through qualitative/colorimetric and quantitative/fluorimetric methods. When tested with spiked milk and eggs, the sensor showed excellent recovery, demonstrating its potential for food safety applications . Section title: IFE-based detection mechanism Educational score: 4.327422618865967 Domain: biomedical Document type: Study Language: en In this study, CDs were synthesized using 4-hydroxybenzoic acid and ethylenediamine, with 4-nitrophenyl-α-D-glucopyranoside (NGP) serving as the substrate for the enzyme α-glucosidase. The enzyme catalyzed the release of 4-nitrophenol from NGP. Acarbose, a common anti-diabetes drug, was used as an inhibitor in the assays. The addition of acarbose inhibited α-glucosidase activity, leading to a recovery of FL intensity, as shown by an increase in FL when inhibitors were added. The sensor exhibited minimal interference from other substances, demonstrating its high selectivity and applicability for detecting α-glucosidase activity . CDs were synthesized using diammonium hydrogen citrate and PEG-400 via a microwave-assisted method. The resulting CDs were evaluated for cytotoxicity and cell imaging, with their FL intensity showing a pH-dependent behavior. The study also investigated the FL-quenching effects of various metal ions, finding that Fe 3+ had the most significant impact. This quenching was attributed to energy transfer processes within the excited CDs. Additionally, the CDs were successfully used for cellular imaging in BGC-823 and CT26.WT cells, showcasing their potential as optical nanoprobes for cell imaging applications due to their high FL brightness . Mg-doped carbon dots (Mg-CDs) were synthesized using a simple, one-pot microwave-assisted method by dissolving citric acid in a magnesium chloride (MgCl 2 ) solution and mixing it with ethylenediamine. The resulting Mg-CDs nanoprobes (Mg-CDs-0.1) demonstrated high selectivity and sensitivity for detecting hematin due to the strong IFE between Mg-CDs and hematin. Specificity tests revealed that Mg-CDs-0.1 showed a significant FL intensity reduction only in the presence of hematin, with no impact from other molecules or metal ions. Similar results were observed with Mg-CDs-0.5, confirming their high reproducibility and selectivity for detecting hematin in human red cell hemolysate . Section title: IFE-based detection mechanism Educational score: 4.457662105560303 Domain: biomedical Document type: Study Language: en Carbon dots (CDs) were synthesized from environmentally friendly pomegranate juice using a simple hydrothermal method and tested as sensitive indicators for detecting cefixime (CEF). The detection method relies on the interaction between palladium ions (Pd (II)) and CEF in an acidic buffer (pH 4). The excitation spectra of the synthesized CDs and the Pd (II)-CEF complex were found to overlap, leading to a decrease in FL intensity when both CEF and Pd (II) were present, enabling quantitative detection of CEF. The technique showed minimal interference from other ions and biomolecules. The method was successfully applied to analyze urine samples from a healthy individual and pharmaceutical formulations, demonstrating its potential for rapid CEF detection in real samples . A rapid and efficient microwave-assisted method was used to synthesize glycerol-urea CDs (GUCDs). The ability of GUCDs to detect antibiotics in urine samples was tested by adding various compounds, including antibiotics, to GUCDs solutions. The FL signal of GUCDs remained mostly unaffected by the presence of other molecules, except for tetracycline (TC) antibiotics (TC, doxycycline, and oxytetracycline (OTC)), which significantly altered the responses. The FL intensity of GUCDs was pH-dependent, with the highest emission observed at pH below 4.0. This pH was chosen to maximize the FL signal and prevent TC degradation. As a result, a simple, low-cost method based on the reduction of GUCDs FL was developed to detect TC in urine samples, indicating the high selectivity of GUCDs for TC antibiotics . In a study focused on the development of a fast FL sensor, CDs were synthesized using hawthorn, and the sensor was designed to detect chlortetracycline (CTC) in pork samples. The results showed that substances like CAP, sulfanilamide, and florfenicol did not interfere with the sensor's reaction system. However, TC antibiotics (such as TC, doxycycline, and OTC) did affect the FL response, with TC having the strongest impact. This highlighted that the N-CDs were particularly selective for detecting TC antibiotics, making them useful for detecting harmful substances in food . The europium doped carbon dot (Eu-CDs) were synthesized using citric acid, melamine, and Europium (III) Nitrate Hexahydrate (Eu(NO₃)₃·6H₂O) in a one-pot hydrothermal method, with Eu serving as a TC-binding site and providing FL. Formaldehyde was added as a passivating agent to modify the nitrogen's chemical state in the Eu-CDs. The study found that the maximum FL intensity ratio for both TC and Al³⁺ occurred at pH 8.0, which was identified as the optimal pH. The Eu-CDs exhibited stable FL and color, unaffected by biological ions or other antibiotics. Notably, only TC caused a significant FL enhancement at 620 nm and a color shift from blue to red, demonstrating the Eu-CDs' high selectivity for TC detection . In a separate study, B-CDs were synthesized with the help of salicylic acid, melamine, and distilled water, incorporating zinc nitrate hexahydrate and 2-methylimidazole. The CDs were then modified into a hierarchical mesoporous zeolitic imidazolate framework-8 (HZIF-8) using hydrogel as a template. The specificity of the CDs@HZIF-8 system for TC was evaluated by introducing various potential interfering substances, such as metal ions, amino acids, vitamins, and antibiotics. The results showed that the sensor maintained excellent selectivity and anti-interference capacity for TC, confirming its robustness for real-world applications . A novel FL sensor was developed using nitrogen-doped carbon dots (N-CDs) embedded in zinc-based metal-organic frameworks and molecularly imprinted polymer (ZIF-8&N-CDs@MIP). This sensor, optimized at pH 7, demonstrated high sensitivity and selectivity for TC, with minimal interference from its structural analogs, such as CAP, OTC, and CTC. The sensor showed excellent selectivity, improved sensitivity, and fast response times for detecting TC . N-CDs were synthesized using pitaya peel and 1,2-ethylenediamine via a hydrothermal method. The N-CDs exhibited a “turn-off” FL response when interacting with TC and OTC, while showing a “turn-on” FL response with CTC, making them highly sensitive for CTC detection. Selectivity tests demonstrated that the FL intensity of N-CDs was minimally affected by other potential interfering substances, including metal ions, antibiotics, amino acids, and anions. The sensor proved to be a versatile, dual-mode platform for detecting TC with high sensitivity and adaptability. For example, the schematic illustration of the synthetic process of N-CDs and their application as a multifunctional nano-sensor for sensing TC, OTC, and CTC is shown in Fig. 8 . Fig. 8 Schematic illustration of synthetic process of N-CDs and application as a multifunctional nano-sensor for sensing of TC, OTC, and CTC. Fig. 8 Section title: IFE-based detection mechanism Educational score: 4.17685079574585 Domain: biomedical Document type: Study Language: en In this study, CDs were synthesized using trimesic acid and 4-amino acetanilide hydrochloride through a one-step hydrothermal process. This method involved combining glucose solutions of varying concentrations with glucose oxidase (GOx) in a Britton-Robinson buffer at 37 °C for 40 min to produce hydrogen peroxide (H 2 O 2 ). When CDs were added to the mixture, their FL was quenched by H 2 O 2 , with the quenching intensity being directly proportional to the H 2 O 2 concentration, enabling glucose detection. The method showed good sensitivity and selectivity when tested with biological samples, including human serum and urine from diabetic and healthy individuals. Additionally, B, N-doped CDs were synthesized using ammonium citrate and bis(pinacolato)diboron via a hydrothermal method. Interference studies revealed that nimesulide significantly quenched the FL, while other substances had little to no effect. This demonstrated the high sensitivity and selectivity of the sensor. Furthermore, the B, N-CDs proved useful for fluorescent staining and anti-counterfeit applications. The method was successfully applied to pharmaceutical samples for detecting Nimesulide . Section title: IFE-based detection mechanism Educational score: 4.219357013702393 Domain: biomedical Document type: Study Language: en N and Cl-functionalized CDs (N, Cl-CDs) were synthesized quickly and environmentally using glucose, ethylenediamine, and HCl. The FL intensity of the N, Cl-CDs was rapidly quenched by curcumin (Cur), indicating its effective interaction with the CDs. Selectivity tests showed that Cur was the only substance among the investigated compounds that significantly reduced the FL intensity, while other potential interfering substances had little to no impact. This demonstrates that N, Cl-CDs exhibit high selectivity for Cur and are unaffected by interference from other drugs, making them a promising tool for Cur detection . A study developed a label-free probe for detecting cytochrome c (Cyt C) using nitrogen and fluorine co-doped carbon dots (N, F-CDs), which were easily synthesized through a solvothermal method using 3,4-difluorophenylhydrazine as a precursor. The results demonstrated that the N, F-CDs probe exhibited excellent anti-interference properties, making it a promising candidate for detecting Cyt C. Additionally, the probe showed potential as a temperature sensor with higher sensitivity, suggesting its broad application in biosensing . Section title: IFE-based detection mechanism Educational score: 4.1718268394470215 Domain: biomedical Document type: Study Language: en In this study, CDs were synthesized using ammonium citrate and ammonium thiocyanate through a hydrothermal process. The addition of Cu 2 ⁺ initially increased the FL intensity of the CDs. However, when clioquinol (CQ) was introduced, its high affinity for Cu 2 ⁺ displaced Cu 2 ⁺ from the CDs surface, leading to FL quenching due to IFE. The study examined the effects of pH, ionic strength, and UV exposure time on the FL intensity. The difference in FL intensity between the CDs + Cu 2 ⁺ system and the CDs + Cu 2 ⁺ + CQ system was greatest at pH 8.0. Cu 2 ⁺ adsorbed on the CDs surface, stabilizing them and preventing non-radiative recombination, which increased FL intensity. A new UV absorption peak confirmed the formation of the Cu 2 ⁺-CQ complex. Interference studies showed that CQ could significantly quench the FL of CDs, while other metal ions had negligible effects. This system was proposed as a fluorescent sensor for detecting CQ . Section title: IFE-based detection mechanism Educational score: 4.088705062866211 Domain: biomedical Document type: Study Language: en Silicon-doped carbon quantum dots (Si-CQDs) were synthesized through a straightforward one-pot hydrothermal method using 3-aminopropyltrimethoxysilane and H 2 SO 4 . The pH had no significant effect on the FL behavior of the Si-CQDs. The study also examined how the FL intensity of Si-CQDs was influenced by the addition of various metal ions, amino acids, saccharides, and other substances that could be found in urine samples. Among these, only berberine hydrochloride (BH) caused a significant reduction in FL intensity, while other drugs had minimal effects. These results demonstrate that the developed sensor has high sensitivity and selectivity for BH detection . Section title: IFE-based detection mechanism Educational score: 4.187173843383789 Domain: biomedical Document type: Study Language: en Chitosan was utilized as a C and N source in the carbonization process to develop a fluorescent sensor. The FL of the resulting probe was effectively quenched by diacerein (DIA), producing rapid and stable FL responses. The sensing system demonstrated high precision and accuracy, allowing for the selective detection of DIA in its tablet dosage form, even in the presence of co-formulated medications . Rhodamine B was dissolved in ultrapure water and used in a solvothermal process to synthesize CDs. Various chemicals, including sugars (glucose, sucrose), inorganic ions (K + , Na + , Ca 2+ , Cl − , NO 3 − ), amino acids (histidine, alanine, threonine, phenylalanine, arginine), and medications (paracetamol, artemisinin), were tested for their impact on the sensor. When these substances were added individually without captopril (CP), there was no significant change in the FL and absorbance signals. However, the addition of CP led to a substantial enhancement in both FL and absorbance signals. These results demonstrated the high selectivity and robustness of the CP sensor, which was able to tolerate interference from coexisting chemicals . Section title: IFE-based detection mechanism Educational score: 4.137907028198242 Domain: biomedical Document type: Study Language: en Using a one-pot green synthesis method, a green bell was chosen to produce CDs due to its high-quality contents, including carotenoids, ascorbic acid, carbohydrates, and other carbonaceous organic compounds. To create MSA-CdTe quantum dots (QDs), cadmium chloride (CdCl 2 ), mercaptosuccinic acid (MSA), sodium tellurite (Na 2 TeO 3 ), and a borate-acetic acid buffer solution were combined. Then, Si@CdTe QDs were synthesized using MSA-CdTe QDs, 3-Aminopropyl triethoxysilane (APTES), and ethanol. The ideal pH for detecting doxorubicin (DOX) and daunorubicin (DAN) was found to be pH 7. Sodium chloride (NaCl) did not cause significant changes in the signal intensity, which was used to assess the impact of potential interferents like glutamine, fructose, and glucose in biological samples. These results demonstrated that the ratiometric fluorescence (RF) sensors were highly effective in detecting both DAN and DOX . Section title: IFE-based detection mechanism Educational score: 4.397334575653076 Domain: biomedical Document type: Study Language: en Red-emission carbon dots (R-CDs) were synthesized using a solvothermal process involving formamide, N, N-dimethylformamide, and citric acid. The optimal pH for the reaction system was found to be 6.0. When used as a fluorescent probe for detecting mitoxantrone (MITX), R-CDs exhibited excellent selectivity and resistance to interference, as the presence of interference compounds had little to no effect on either the R-CDs or the R-CDs-MITX system's FL. The developed label-free fluorescent nanoprobe proved to be highly effective for the rapid and accurate detection of MITX in human serum samples . The green tea leaf residue was used as the carbon source for synthesizing carbon dots (named as T-CDs) employing a combination of high-temperature pyrolysis and oxidation with concentrated H 2 SO 4 . The FL intensity of the T-CDs was found to decrease as the concentration of gefitinib increased, with the FL quenching effect being proportional to the drug concentration. Selectivity tests revealed that no other substances at a concentration of 20 μg/mL significantly affected the FL of T-CDs, except for gefitinib, indicating the high specificity of T-CDs for gefitinib detection. The method utilized the IFE of gefitinib to quench the FL of T-CDs, and it was successfully applied to detect gefitinib in urine samples . A study developed a FL probe for detecting DOX using plum-based carbon quantum dots (PCQDs) synthesized via a simple bottom-up method. This ratiometric FL probe was tested on urine and serum samples, which may contain interfering substances. The results showed that, apart from DOX, the absorption peaks of interfering chemicals did not overlap with the emission peak of the PCQDs. Only DOX significantly increased the I591/I491 ratio of the PCQDs, indicating a strong response. The probe exhibited high selectivity for DOX over other drugs, such as cytarabine, cytoxan, 5-fluorouracil, and methotrexate, which had no effect on the I591/I491 readings. This demonstrated that the presence of other substances did not interfere with the detection of DOX, making the probe a reliable and selective tool for DOX detection in complex samples . Section title: IFE-based detection mechanism Educational score: 4.060974597930908 Domain: biomedical Document type: Study Language: en Plant-based sulfur and nitrogen self-co-doped carbon quantum dots (S, N-CQDs) were synthesized in an environmentally friendly, cost-effective, and rapid one-pot process using onion and cabbage juices and distilled water. The optimal pH for the procedure was determined to be 8.0. The applicability of the synthesized S, N-CQDs for FL sensing of nitazoxanide and hemoglobin (Hb) was evaluated by testing their response to various potential interfering substances, including glycine, glucose, sucrose, citric acid, sodium benzoate, sodium citrate, urea, lysine, nicotinamide, glutathione, and various ions (Ca 2 ⁺, K⁺, Na⁺, Mg 2 ⁺, Cl⁻, SO₄ 2 ⁻). The results demonstrated that these green, safe, affordable, and sustainable S, N-CQDs have significant potential for use in pharmaceutical and biological applications . Section title: IFE-based detection mechanism Educational score: 4.068040370941162 Domain: biomedical Document type: Study Language: en N-CDs were synthesized using diethylenetriamine and citric acid through a hydrothermal process. The FL intensity of the sensor decreased linearly with an increase in myricetin concentration. The sensor showed high selectivity for myricetin, as its signal intensity was unaffected by various structural analogs such as warfarin, KAE, and luteolin, among others. Additionally, the sensor exhibited strong anti-interference properties, with minimal impact from potential interfering ions or compounds, ensuring reliable detection of myricetin. The schematic diagram of the preparation process of N-CDs and the detection principle for myricetin is shown in Fig. 9 . Fig. 9 Schematic diagram about the preparation process of N-CDs and detection principle for myricetin. Fig. 9 Section title: IFE-based detection mechanism Educational score: 4.1621880531311035 Domain: biomedical Document type: Study Language: en Water-soluble carbon dots (SD-CDs) were synthesized using a microwave-assisted approach with 5-sulpha anthranilic acid (SAA) and 1,5-diphenylycarbazide (DPC) as precursors. The selectivity of SD-CDs towards levocetirizine and niflumic acid was investigated in the presence of various metal ions (Na + , Ni 2+ , Mn 2+ , Cd 2+ , K + , Ca 2+ ), anions (Br − , SO 4 2− , Cl − , NO 3 − ), and drugs. The results showed that the FL intensity of SD-CDs was enhanced exclusively by levocetirizine, even in the presence of other interfering substances. On the other hand, niflumic acid caused a significant FL quenching when mixed with other chemicals, demonstrating a high selectivity of SD-CDs for these two compounds. The addition of metal ions, anions, and other drugs did not result in FL enhancement or quenching, confirming the robustness and specificity of SD-CDs. These findings indicate that SD-CDs could serve as a reliable analytical platform for detecting levocetirizine and niflumic acid in real-world samples . Section title: IFE-based detection mechanism Educational score: 4.189867973327637 Domain: biomedical Document type: Study Language: en Orange-emission fluorescent multifunctional carbon dots (O-CDs) were synthesized using safranine T and ethanol through a one-step hydrothermal process. These O-CDs exhibit excitation-independent FL properties, making them suitable for applications in biosensing, cellular labeling, and photovoltaic materials. When tested for selectivity, O-CDs showed significant FL quenching only in the presence of vitamin B 12 (VB 12 ), indicating their high selectivity for VB 12 analysis. The O-CDs also demonstrated a longer FL emission duration compared to other fluorescent techniques for VB 12 analysis, making them highly effective for detecting VB 12 in biological samples. The mechanism of FL quenching was attributed to IFE, confirmed through UV–Vis absorption spectra and lifetime measurements, showing that VB 12 absorbed the excitation spectrum of O-CDs, leading to FL quenching. This specificity was further validated as the FL did not change in the presence of amino acids or other vitamins . Section title: PET-based detection mechanism Educational score: 4.098095893859863 Domain: biomedical Document type: Study Language: en In a study using a high-pressure microwave method, biomass CDs were synthesized from longan peels. To enhance the selectivity and sensitivity of the fluorescent probes, CDs were integrated with molecularly imprinted polymers (MIPs) and restricted access materials (RAM-MIPs), resulting in the creation of CDs@RAM-MIPs. The results showed that CDs@RAM-MIPs exhibited excellent selectivity for metronidazole (MNZ), with no significant interference from other drugs. The unique recognition cavities of the CDs@RAM-MIPs selectively bind MNZ, allowing for precise detection of the target molecule. The method's applicability was also evaluated by measuring MNZ levels in serum samples, demonstrating its potential for accurate detection in complex biological samples . Section title: On, off, and off-on based detection mechanism Educational score: 4.205321788787842 Domain: biomedical Document type: Study Language: en Fluorescent CDs were synthesized by a microwave-assisted method using a mixture of coconut water and ethanol (1:1 v/v). The resulting CDs displayed luminescent properties, which were influenced by the reaction temperature and microwave exposure time during the synthesis. The study showed that pure coconut water itself did not exhibit any FL, but the CDs produced during the microwave reaction displayed strong FL. These CDs were then used as a sensing platform for thiamine detection. The FL of the CDs was quenched by the addition of Cu 2+ ions. However, when thiamine was added to the mixture of CDs and Cu 2+ , the FL intensity was restored to its original value. This restoration of FL intensity was directly proportional to the concentration of thiamine, allowing for the quantification of thiamine in real samples such as blood and urine. The method proved highly selective for thiamine, with minimal interference from other potentially coexisting molecules and ions. This makes the CDs a useful tool for thiamine analysis in biological samples, demonstrating a practical and sensitive approach to thiamine detection . Section title: On, off, and off-on based detection mechanism Educational score: 4.145735740661621 Domain: biomedical Document type: Study Language: en In a separate study, N-CDs were synthesized using a hydrothermal method to detect zoledronic acid (ZA) in blood serum. The N-CDs exhibited a FL intensity change when ZA was added. Specifically, the FL was quenched when Fe 3+ ions were present, but it was restored upon the introduction of ZA, forming a complex with Fe 3+ . The optimal pH for this FL sensing system was found to be 4.0, using an acetate buffer. This method showed high selectivity for ZA, as there were no significant FL changes when other molecules or ions, even in excess, were added. The study also compared the FL response of ZA to other substances like fludarabine (FLD), a chemotherapy drug, and found that FLD did not interfere with the sensing process. This demonstrates that the N-CDs-Fe 3+ complex can be effectively used for selective and sensitive detection of ZA in blood serum, highlighting the potential of N-CDs for chemical sensing and medical applications . Section title: On, off, and off-on based detection mechanism Educational score: 4.0425519943237305 Domain: biomedical Document type: Study Language: en Saffron was used as a precursor to synthesize CDs through a hydrothermal method, offering a novel and cost-effective approach. The fluorescent properties of these CDs enabled the sensitive detection of prilocaine in human plasma. Additionally, the synthesized CDs were applied for bioimaging, specifically for imaging olfactory mucosa cells and bone marrow cells. The results demonstrated excellent imaging capabilities, suggesting that these saffron-derived CDs are promising candidates for bioimaging applications, particularly in cancer cell imaging. This highlights their potential for medical and diagnostic use . Section title: On, off, and off-on based detection mechanism Educational score: 4.104832649230957 Domain: biomedical Document type: Study Language: en The researchers synthesized N-CDs using DL-malic acid and glycine. Initially, adding enrofloxacin (ENR) to the N-CDs caused no change in the FL intensity or shape, indicating no interaction between the two. However, the introduction of Cu 2+ restored the FL of the N-CDs, suggesting that Cu 2+ interacts with both ENR and the N-CDs. Additionally, the concentration of N-CDs in the solution increased with the addition of Cu 2+ , likely due to the aggregation of some N-CDs or the formation of larger complexes between Cu 2+ and ENR. This approach was shown to selectively detect ENR in tap and river water samples, demonstrating its potential for environmental monitoring . Section title: On, off, and off-on based detection mechanism Educational score: 3.9464495182037354 Domain: biomedical Document type: Study Language: en In a study, the FL intensity of CDs increased with rising concentrations of CTC, with a blue shift in the emission peak. This sensor showed excellent selectivity for CTC over other TC antibiotics, structurally similar drugs, various ions, and naturally occurring amino acids. The sensor was also effective in detecting CTC in milk and tap water, indicating its application in food safety and environmental testing . Section title: On, off, and off-on based detection mechanism Educational score: 4.075961112976074 Domain: biomedical Document type: Study Language: en Moreover, N, S-CDs were synthesized using a one-pot ionothermal method with deep eutectic solvent and microcrystalline cellulose (MCC) as solvents and dopants. These N, S-CDs were used to detect glutathione (GSH), where the FL quenching caused by the formation of a CD-Cu 2+ complex was reversed by adding GSH. The interaction between GSH and Cu 2+ restored the FL, and as GSH concentration increased, the FL became more intense. This work demonstrated that GSH is selective for the recovery of CD FL, and the study also evaluated the impact of interfering substances like amino acids and small reducing molecules. The findings suggest broad applications for biomass-derived carbon dots in selective FL sensing. The schematic illustration of the preparation of N, S-CDs and their detection capabilities for Cu 2 ⁺, and GSH is shown in Fig. 10 . Fig. 10 Schematic preparation of N, S-CDs and its detection for Cu 2+ and GSH. Fig. 10 Section title: On, off, and off-on based detection mechanism Educational score: 4.182375431060791 Domain: biomedical Document type: Study Language: en Food-derived crawfish shells were utilized as green precursors to synthesize N, S-CDs via a hydrothermal method. The FL of the N, S-CDs was significantly quenched upon the addition of H 2 O 2 and horseradish peroxidase (HRP). This quenching occurred because the hydroxyl radicals generated by the reaction between H 2 O 2 and HRP oxidized the surface groups (N, sulfur, and oxygen) of the N, S-CDs, altering their surface states and causing FL suppression. However, when pentachlorophenol (PCP) was introduced to the NSCDs@HRP/H 2 O 2 system, the FL was restored. PCP provided a reducing environment that prevented the oxidation of the active groups on the N, S-CDs, thus reactivating the FL. This fluorescent sensing method proved highly effective for detecting PCP in real samples, highlighting the potential of this approach for environmental and analytical applications . Section title: Quenching-based detection mechanism Educational score: 4.182999610900879 Domain: biomedical Document type: Study Language: en In one study, CDs were synthesized through hydrothermal treatment using glucose, ampicillin, 2-phenyl glycine, and (+)-6-amino penicillanic acid. The β-lactam subunit within ampicillin, with its N and S atoms, was identified as the key factor contributing to the unique absorption and emission properties of the resulting CDs. Unlike a glucose solution without hydrothermal treatment, the product solutions containing varying amounts of ampicillin exhibited distinct FL, showcasing the significant role of ampicillin in the FL properties of the CDs . In a study involving co-doped CNDs containing N and phosphorus (P), the synthesis was achieved using FA through a single-step solvothermal method. The interference study showed that the FL intensity of the CNDs remained almost unchanged when exposed to common excipients like lactose, L-ascorbic acid, talc, magnesium tartrate, and starch, suggesting that these substances did not interfere with the analytical method. This indicates the reliability of the CND-based sensor. Furthermore, in vivo studies revealed that the CNDs had no significant cytotoxic, hematological, or biochemical effects on animals, supporting their biocompatibility . Section title: Quenching-based detection mechanism Educational score: 4.067259788513184 Domain: biomedical Document type: Study Language: en In another study, Cedrus was used as a green source for producing CDs through a hydrothermal method. These CDs were then modified with MIPs using reverse micro-emulsion technology, resulting in MIPs-Green Source CDs (MIPs-GSCDs). The sensor was optimized in terms of pH, temperature, and response time. The MIPs-GSCDs exhibited high sensitivity and selectivity for phenobarbital in human blood plasma, demonstrating the practical application of this sensor for real sample analysis . Section title: Quenching-based detection mechanism Educational score: 4.097076416015625 Domain: biomedical Document type: Study Language: en A separate study used citric acid and ammonia to synthesize CDs through pyrolysis at high temperatures. These CDs were tested for their selectivity in plasma and pharmaceutical formulations, particularly in the presence of potential interfering substances. While most compounds had little effect on the FL of CDs, clonazepam caused a significant quenching of FL, likely due to interactions between its nitro group and the surface functional groups of the CDs. This high selectivity allows for the precise detection of clonazepam in low concentrations, making the sensor valuable for monitoring trace amounts in pharmaceutical and plasma samples . Section title: Quenching-based detection mechanism Educational score: 4.137552261352539 Domain: biomedical Document type: Study Language: en Additionally, red-emitting copper nanoclusters (CuNCs) were synthesized using DNA as a template and combined with blue-emitting CDs to form a self-assembled complex, DNA-CuNC/CDs. This complex was tested as a ratiometric FL nanoplatform for detecting arginine (Arg) and acetaminophen (AP) in human serum samples. Upon the addition of AP, the FL of the complex shifted from purplish-red to blue, and the FL of the CDs was restored, demonstrating the ability to detect AP. The system showed excellent selectivity and sensitivity, with minimal interference from other substances. This ratiometric FL nanoplatform also highlighted the potential for building “INHIBIT” logic gates at the molecular level, offering exciting prospects for early disease diagnosis and real-time clinical monitoring . Section title: Quenching-based detection mechanism Educational score: 4.232675552368164 Domain: biomedical Document type: Study Language: en A microwave-assisted method was used to synthesize CDs from glucose and deep eutectic solvents (DESs), composed of choline chloride and urea mixed with deionized water. The CDs were tested for FL properties by mixing them with various ions and molecules at a concentration of 3 μM. The FL intensity remained mostly unaffected by most species, except for atorvastatin, which caused significant quenching, indicating the sensor's high selectivity for atorvastatin. FL quenching occurred quickly at room temperature after adding atorvastatin. The FL intensity was pH-dependent, increasing between pH 3–8, with a peak at pH 7.4, which was chosen as the optimum pH for the sensor. The FL intensity decreased significantly with increasing atorvastatin concentration, demonstrating the CDs sensitivity for atorvastatin detection. Nitrogen and chloride-doped carbon dots (N/Cl-CDs) were synthesized using the same method to enhance the sensor's selectivity and sensitivity. These N/Cl-CDs were successfully used as a fluorescent nanosensor to detect atorvastatin in blood, showcasing their potential for monitoring atorvastatin in biological samples . Section title: Quenching-based detection mechanism Educational score: 4.196703910827637 Domain: biomedical Document type: Study Language: en Hydrothermal synthesis was used to create nitrogen and phosphorus co-doped carbon dots (N, P-CDs) with intense blue FL using alanine and diammonium phosphate. The FL intensity remained stable with an increase in pH until DOX was introduced, which caused a significant decrease in the FL intensity, indicating that the N, P-CDs were sensitive to DOX. The FL intensity reached its peak at pH 7.0, and with increasing concentrations of DOX, the FL intensity gradually reduced. When tested against various common metal cations and biomolecules, only DOX caused a marked “turn-off” effect, demonstrating the high selectivity of the N, P-CDs for DOX detection . Thiosemicarbazide and citric acid were utilized in a one-step hydrothermal method to synthesize nitrogen and sulfur-doped carbon quantum dots (N, S-CQDs). These N, S-CQDs demonstrated strong FL and were used for the detection of imatinib (IMA) in pharmaceutical and biological samples. As the concentration of IMA increased, the FL intensity of the N, S-CQDs decreased, providing a simple and sensitive approach for IMA detection, with the added benefits of low cost and ease of use. The systematic detection process of imatinib is depicted in Fig. 11 . Fig. 11 Outline of the synthesis process and applications of N,S-CQDs. Fig. 11 Section title: Quenching-based detection mechanism Educational score: 4.293525695800781 Domain: biomedical Document type: Study Language: en Similarly, a fluorescent sensor for Cur detection was developed based on N, S-CQDs and MIPs. The CQDs with blue FL were synthesized using citric acid and o-phenylenediamine. The sensor, composed of N, S-CQD@MIP, showed higher quenching efficiency for Cur compared to the N, S-CQD@NIP composite, highlighting its superior sensitivity. Even when the concentration of interfering drugs was ten times higher than Cur, the FL quenching efficiency remained largely unaffected, demonstrating excellent selectivity for Cur. Further tests with various ions and proteins confirmed that the sensor was highly selective and specific for Cur detection . Highly luminous CDs were synthesized from wild lemon leaves using one-step microwave pyrolysis. The selectivity of the CDs was tested by introducing a variety of foreign substances, including biomolecules, metal ions, and antibiotics. The CDs demonstrated exceptional selectivity for TC detection, as they remained highly fluorescent even in the presence of various interferents. This biocompatible, label-free nanoprobe was successfully used to detect TC in environmental water samples, showing good recovery rates and promising potential for environmental monitoring . Section title: Quenching-based detection mechanism Educational score: 4.064757823944092 Domain: biomedical Document type: Study Language: en Researchers synthesized Aconitic acid-based carbon dots (AA-CDs) using aconitic acid (AA) and 1,2-ethylenediamine via a hydrothermal method. They found that the addition of FA could effectively quench the intrinsic FL of AA-CDs without requiring additional surface modifications or passivation. The AA-CDs were successfully used for detecting FA in food and pharmaceutical samples. Additionally, the researchers demonstrated the potential of FA-AA-CDs for targeted imaging, as they were able to distinguish cancer cells based on varying levels of folate receptor's (FRs) expression. This showed the feasibility of using turn-on FL for imaging cancer cells with overexpressed FRs indicating a promising application for cancer diagnostics and imaging. Fig. 12 presents a schematic illustration of ratiometric FL sensing for FA . Fig. 12 Schematic illustration for the detection of folic acid. Fig. 12 Fig. 13 Various applications of CDs. Fig. 13 Section title: Quenching-based detection mechanism Educational score: 4.093809127807617 Domain: biomedical Document type: Study Language: en A new type of fluorescent CDs was synthesized by pyrolyzing folic acid. These fluorescent CDs exhibit excitation-independent FL, allowing for rapid and sensitive detection of isoniazid through a combination of IFE and SQ effects. This makes them promising for drug testing applications, potentially offering new methods and technologies for detecting pharmaceutical compounds . Another study focused on the synthesis of fluorescent nitrogen-doped carbon quantum dots (N-CQDs) using a hydrothermal process involving natural osmanthus fragrans, without the use of harmful substances or surface chemical modifications. In tests for potential interference, the FL intensity of N-CQDs remained stable when mixed with various metal cations, indicating that they are highly selective for quercetin (QT) sensing. These N-CQDs can serve as a reversible, sensitive platform for detecting QT, making them suitable for clinical diagnostics and other biomedical applications . Section title: Quenching-based detection mechanism Educational score: 4.112274646759033 Domain: biomedical Document type: Study Language: en Additionally, Fluorine, Nitrogen-doped carbon dots (F, N-CDs) were synthesized using tetrafluoroterephthalic acid and tetraethylenepentamine. These F, N-CDs exhibited a rapid decrease in FL intensity as the concentration of tigecycline (TIGE) increased. The FL quenching effect was highly specific, as other potential interferences showed minimal impact. The method demonstrated strong anti-interference properties, making it suitable for real-time drug monitoring. The approach was successfully applied for detecting labeled TIGE and TIGE injections in human plasma, highlighting its potential for precise and reliable drug monitoring in clinical settings . Section title: Quenching-based detection mechanism Educational score: 4.3450026512146 Domain: biomedical Document type: Study Language: en A sensor was developed by coupling ovalbumin (OVA) and 3-aminophenyl boronic acid (3-APBA) with CDs through the specific interaction of cis-diol bonds in glycoproteins and borate groups on the CDs surface. This CDs-functionalized OVA acted as both a stabilizing and reducing agent during the synthesis of gold nanoclusters (AuNCs), forming a CDs-AuNCs nanocomposite. The sensor demonstrated the highest ratiometric FL efficiency at pH 8.5, producing a bright yellow color. The sensor was tested for TC detection, showing high selectivity and minimal interference from other antibiotics, amino acids, and potential contaminants. This triple-emission sensor is highly selective for tetracyclines (TC's) and has potential for practical applications in antibiotic detection . In a single step, CDs were synthesized using GSH and formamide via a microwave-mediated process. Interference studies demonstrated that the CDs were highly selective for detecting nitrotyrosine (nTyr), even in the presence of other biologically significant compounds like tyrosine (Tyr) and phosphotyrosine (pTyr). Without nTyr, the FL emission of the CDs was only slightly reduced (by 10 %) in the presence of these interferents, indicating that the CDs were specifically designed for nTyr detection with minimal interference . Section title: Quenching-based detection mechanism Educational score: 4.148980617523193 Domain: biomedical Document type: Study Language: en The CDs were synthesized using a hydrothermal method with citric acid as the carbon source and ethylenediamine as the co-reactant. These CDs were employed as probes to detect dopamine (DA) and DOX in human serum solutions. In the serum, DA effectively quenched the FL of the CDs, establishing a strong linear correlation. Similarly, DOX was also detected with a good linear relationship in the serum solution. The results indicate that CDs are highly suitable for detecting DA and quinone-based drugs, such as DOX, in human serum due to their excellent stability, eco-friendliness, and anti-interference properties. The method was also successfully applied to quantitatively identify DOX and MITX, both of which share a typical quinone structure. This approach provides a solid foundation for further biological applications, offering reliable and efficient detection capabilities in clinical and pharmaceutical settings . Section title: Quenching-based detection mechanism Educational score: 4.298068046569824 Domain: biomedical Document type: Study Language: en Fluorescent CDs were synthesized using citric acid and L-glutathione to create a platform for detecting chondroitin sulfate (CS). The positively charged N-doped CDs (P-NCDs) were combined with FAM-labeled random-sequence single-stranded DNA (F-ssDNA), creating a sensitive and simple ratiometric homogeneous assay through competitive electrostatic interactions. The process of CS detection was confirmed by measuring the zeta potential, which decreased due to the electrostatic interaction between negatively charged CS and P-NCDs/F-ssDNA. The zeta potential decreased significantly when CS was added, showing a stronger interaction between P-NCDs and CS (−12.5 mV) compared to P-NCDs and F-ssDNA. Further validation was achieved by comparing the zeta potential of P-NCDs with CS (−4.5 mV) to that of their mixture (−19.75 mV). The system was successfully applied to detect CS in actual joint fluid, demonstrating its potential for clinical use. This study highlights new insights into the development of fluorescent nanomaterials and DNA for biosensing applications . Section title: Quenching-based detection mechanism Educational score: 4.095549583435059 Domain: biomedical Document type: Study Language: en CDs were synthesized using CO(NO 3 ) 2 .6H 2 O and cetrimonium bromide (CTAB), followed by dispersion with multi-walled carbon nanotubes (MWCNTs) via ultrasonication. The FL intensity of the CDs was found to be pH-dependent, with the highest redox peak current observed at pH 7.0 for the drug molecules flutamide (FLU) and nitrofurantoin (NF). The sensor was evaluated for practical use in human urine samples, showing its capability for the simultaneous detection of these drug molecules. This study demonstrates a straightforward method for synthesizing a hybrid nanocomposite and highlights its potential for drug detection applications . Section title: Current challenges and future prospects Educational score: 4.473092555999756 Domain: biomedical Document type: Review Language: en Many pharmaceutical drugs have been detected using HPLC, HPTLC, UV–Vis, and Fourier transform infrared spectroscopy (FT-IR) to date. Analytical experiments (sampling, sample preparation, instrumental analysis, data processing, and data interpretation) present distinct problems in achieving the goal of enhancing the existing state of pharmaceutical analysis and, more broadly, functionalization. To overcome these challenges CDs can be used for detection just by converting the non-fluorescent substances into fluorescent substances and sensing through a different mechanism. Pharmaceutical residues of antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), lipid-regulators, hormones, β-blocker, anticonvulsants, steroids, opiate drugs, antidepressants, and anti-diabetics in the environment have recently been discovered as a hazard, with their presence in the aquatic environment being particularly critical . Experiments conducted in both laboratory and natural settings have revealed that oral contraceptives are leaving traces in water bodies and causing the feminization of fish and amphibians, while psychiatric drugs are leaving residues that alter fish behavior. Furthermore, the excessive use of antibiotics has led to a rapid rise in antimicrobial resistance, which has become a major global health crisis . Previous studies have found that common antidepressant medications are accumulated in the brain tissue of fish that inhabit water downstream from wastewater treatment plants (WWTPs) . Numerous techniques have been proposed for eliminating antibiotics, including advanced oxidation, reverse osmosis, membrane filtration, electrochemical methods, and biological treatments. However, most of these methods are expensive, produce by-products, or are not as efficient. Removal of antibiotics by using various adsorbents (sawdust, activated carbon, NPs, sludge biochar) has been reported. Antibiotics such as gatifloxacin have been removed by more than 90 % using NPs and 68.5 % and 64 % of ciprofloxacin by using kandira stone and sawdust as an adsorbent . The Fenton oxidation process combined with ultrafiltration (UF), sand filtration, reverse osmosis (RO), and nanofiltration (NF) resulted in recovery above 90 %. In another study, the electro-Fenton process was used to remove diclofenac sodium where about 80 % drug removal was observed . Recently, various techniques have been developed to remove antibiotics and antibiotic resistance genes. These techniques include the use of Fe 3 O 4 /red mud NPs, 3D hierarchical porous-structured biochar aerogels, calcined layered double hydroxides, co-doped UiO-66 NPs, Cu@TiO 2 hybrids, bioelectrochemical systems, and aerobic granulation process. The results of studies have shown that most of these methods are effective in removing antibiotic residues and antibiotic resistance genes, with removal rates ranging from 85 % to 95 % . A recent study found that a mix of domestic and livestock sewage in rural wastewater contained five steroid hormones [androsta-1,4-diene-3,17-dione (ADD), 4-androstene-3,17-dione, 19-norethindrone (19-NTD), testosterone (T), and progesterone ] and four biocides [N, N-diethyl-3-methylbenzamide (DEET), triclosan (TCS), carbendazim (CBD), and methylparaben (MP)]. However, the results showed that an integrated constructed wetland (ICW) was able to significantly reduce the levels of the detected hormones and biocides, with a reduction rate of 97.4 ± 0.09 % and 92.4 ± 0.54 %, respectively . Section title: Current challenges and future prospects Educational score: 4.088283538818359 Domain: biomedical Document type: Study Language: en Due to the physical and chemical complexity of the NSAIDs compounds, there is no single method that is sufficiently effective against all types of contaminants . Evidence reveals that pharmaceutical chemicals, physicochemical properties, and structural complexity make them difficult to remove completely in traditional WWTPs, highlighting their unintentional persistence in the environment. There is a toxic effect of pharmaceutical compounds on the human body at low concentrations. Hence, a more sensitive method is required to detect the pharmaceutical compounds at low concentrations, and for this; CDs are the best alternative method to detect the pharmaceutical compounds at the femtogram level. Nowadays, nanomaterials can be used for the treatment of wastewater and purification. Materials such as graphene oxide-based NPs (GONPs), mesoporous Mn x Co 3-x O 4 NPs, etc., have been used for the removal of ibuprofen, ciprofloxacin, and levofloxacin from water and aqueous solution by the mechanism of adsorption mainly due to electrostatic interactions, accelerated electron transfer and by photocatalytic degradation. The percentage removal of ibuprofen, ciprofloxacin, and levofloxacin was found to be 98.2 %, 100 %, and 95 %, respectively [ , , ]. CDs with an optimum size of 5 nm–10 nm and modifying the surface functionalization of CDs can be used for various applications apart from bio-sensing. It includes tumor theranostics (cancer-targeted drug delivery, gene delivery, PTT, photodynamic therapy (PDT)), bio-imaging biomarkers (cell membrane, cytoplasm, for self-targeted bioimaging and diagnosis of tumor cells), catalysis, detection of small molecules, photoacoustic imaging , light-emitting diode (LED) device , FL ink , in agriculture , etc. Section title: Concluding remark Educational score: 4.133532524108887 Domain: biomedical Document type: Review Language: en This review highlights the recent advancements in CDs, focusing on their synthesis, surface functionalization, photoluminescent properties, and diverse applications across fields such as photocatalysis, energy, and sensing. CDs have emerged as promising alternatives to traditional fluorescent compounds, particularly in in-vivo analysis, due to their safer nature and exceptional FL properties. The unique physical and optical characteristics of CDs, including their efficient electron storage and transport capabilities when exposed to light, present vast untapped potential. Looking forward, the development of more reliable and efficient synthesis methods will likely drive further exploration of innovative applications. The versatility of CDs positions them as impactful materials in biotechnology and environmental remediation, offering safer substitutes for conventional analytical techniques. Given the complexity of contaminants that conventional wastewater treatment plants cannot fully eliminate, there is an increasing need for advanced materials like CDs to address these challenges. With their exceptional electron transfer abilities and light-harvesting efficiency, CDs hold significant promise in photovoltaic and photocatalytic applications. Additionally, their potential extends to areas such as bio-sensing, tumor theranostics, bio-imaging, LED technology, small molecule detection, and agriculture. The continued research and development of CDs are expected to unlock new applications, broadening their utility in various scientific and industrial fields. Section title: CRediT authorship contribution statement Educational score: 0.9321514964103699 Domain: other Document type: Other Language: en Sandesh R. Lodha: Writing – original draft, Visualization, Conceptualization. Jesika G. Merchant: Writing – original draft. Arya J. Pillai: Writing – original draft, Visualization. Anil H. Gore: Writing – review & editing. Pravin O. Patil: Writing – review & editing, Writing – original draft. Sopan N. Nangare: Writing – review & editing. Gajanan G. Kalyankar: Writing – review & editing. Shailesh A. Shah: Supervision, Resources. Dinesh R. Shah: Supervision, Resources. Shashikant P. Patole: Writing – review & editing, Supervision, Funding acquisition. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Review | biomedical | en | 0.999998 |
PMC11697699 | Section title: Introduction Educational score: 1.0811604261398315 Domain: other Document type: Other Language: en Math anxiety can be defined as an intensive negative emotional experience associated with math-related tasks (for example, manipulation of numbers) . Academic literature dedicated to math anxiety has increased rapidly in recent years . According to bibliometric research , the majority of studies are dedicated to cognitive correlates of math anxiety, psychological effects, and educational contexts. Section title: Introduction Educational score: 1.0264232158660889 Domain: other Document type: Other Language: en Math anxiety may have a negative impact on math achievements and, as a phenomenon, exists across different cultural contexts . Section title: Introduction Educational score: 1.0844461917877197 Domain: other Document type: Study Language: en There are several cross-cultural comparative studies on math anxiety, such as a comparison between Russia and the UK , Confucian and European countries , the US and Colombia , Finland, the US, and Korea , and Germany and Brazil . The studies provide evidence for a strong cultural influence on math anxiety. For example, students in Confucian countries report higher math anxiety in comparison with European countries . In the present study, we expect to see differences in math anxiety scores between Chinese and Russian schoolchildren due to cultural and educational system differences. Section title: Introduction Educational score: 1.116080403327942 Domain: other Document type: Other Language: en One of the salient results from studies of math anxiety is that girls are more prone to exhibit high math anxiety in comparison to boys . Several studies highlight an increase in math anxiety with age. We also expect to trace those patterns in the current study. Section title: Introduction Educational score: 1.2564622163772583 Domain: other Document type: Other Language: en Abbreviated Math Anxiety Scale (AMAS), developed from Mathematics Anxiety Rating Scale (MARS) by Hopko et al. , was validated for different cultural contexts, including Arabic , Serbian , Turkish , Polish , Spanish , Russian , Italian , German , and Chinese . There is some evidence for age and gender invariance of AMAS , as well as evidence for culture invariance in Italian and English contexts . Among well-established findings from AMAS studies is a higher level of math anxiety for girls , especially in older children . Results regarding age differences are less consistent: while some studies report an increase in math anxiety with age , others highlight an opposite tendency . Section title: Introduction Educational score: 1.5348111391067505 Domain: other Document type: Study Language: en The purpose of the current study is to compare AMAS math anxiety scores for Chinese and Russian schoolchildren. Additionally, factor structure and invariance for Russian and Chinese cultural contexts of AMAS are measured to justify the applicability of AMAS for cross-cultural comparison. Section title: Sample Educational score: 2.171520948410034 Domain: biomedical Document type: Study Language: en The total sample consisted of 7,702 participants (52% girls, M = 13.2, SD = 1.36, Me = 13.0). The Russian sample comprised 4,292 participants (54% girls, M = 13.7, SD = 1.21, Me = 14.0). The Chinese sample comprised 3,410 participants (48% girls, M = 12.7, SD = 1.21, Me = 13.0). The socio-demographic data and age distribution of samples are shown in Supplementary Table 1 and Supplementary Figure 1 . Section title: Instruments Educational score: 1.950072169303894 Domain: other Document type: Other Language: en The Abbreviated Math Anxiety Scale (AMAS) is a 9-item questionnaire developed by Hopko et al. based on the Mathematics Anxiety Rating Scale (MARS). It comprises two subscales: one addressing learning math anxiety (LMA, consisting of five items, e.g., “I feel anxious listening to a lecture in math class”) and the other focusing on math evaluation anxiety (MEA, consisting of four items, e.g., “I feel anxious taking an examination in a math course”). Respondents are required to assess their anxiety levels for each situation described in the statements on a Likert scale ranging from 1 (low anxiety) to 5 (high anxiety). The Russian version of the AMAS has demonstrated strong psychometric properties for middle and high schoolchildren and for high schoolchildren . Similarly, the Chinese version of the AMAS has been validated for primary and middle schoolchildren . Section title: Statistical analysis Educational score: 3.6076548099517822 Domain: biomedical Document type: Study Language: en Statistical analysis was performed in Python (v 3.9) and JASP software . Basic descriptive statistics were used to assess differences in math anxiety in Russian and Chinese samples. Confirmatory Factor Analysis (CFA) was performed to assess the factor structure of AMAS for the two samples. The DWLS (Diagonal Weighted Least Squares) estimator was used. One-factor, two-factor, second-order (two factors), and bi-factor (two factors) CFA models were compared. TLI, CFI, RMSEA, and SRMR metrics were used to assess model fit. Structural Equation Modeling (SEM) analysis was performed to measure invariance, and the Cronbach Alpha coefficient was used to assess the internal consistency of AMAS and subscales for two samples. Section title: Factor structure Educational score: 2.104632616043091 Domain: biomedical Document type: Study Language: en For all samples (the joint, Russian, and Chinese), the bi-factor model with two factors fit the data best (see Table 1 ). Two-factor and second-order models demonstrate acceptable fit statistics in all samples. Factor loadings of the bi-factor model for two samples are presented in Supplementary Tables 3, 4 and Supplementary Figure 2 depict the bi-factor model. Section title: Invariance across countries Educational score: 2.7665140628814697 Domain: other Document type: Study Language: en Structural equation modeling was used to assess whether AMAS works equally for two samples (e.g., whether it is reasonable to compare their scores). During the first stage, configural invariance was tested (i.e., model parameters were estimated for both countries). Secondly, metric invariance was tested (whether factor loadings are the same in Russian and Chinese schoolchildren). Results are presented in Table 2 . Model 1 shows configural invariance with an acceptable fit to the data (CFI = 0.970, RMSEA = 0.069). Model 2 demonstrates metric invariance and fits the data (CFI = 0.965, RMSEA = 0.069). Thus, the data demonstrate an invariance across countries. This means that AMAS is an instrument that can be used to measure cross-cultural differences between Chinese and Russian schoolchildren. Section title: Internal consistency Educational score: 1.7975256443023682 Domain: other Document type: Study Language: en The total AMAS scale and both subscales demonstrate acceptable Cronbach Alpha in both samples (see Table 3 ). There are no differences between Russian and Chinese samples for the total AMAS scale, but subscales, especially the LMA subscale, demonstrate slightly higher internal consistency in the Russian sample. Section title: Descriptive statistics Educational score: 3.876325845718384 Domain: biomedical Document type: Study Language: en Descriptive statistics for total AMAS and two subscales with frequency histograms across the sample are presented in Supplementary Table 4 and Supplementary Figure 3 . It can be seen that regardless of country, the LMA score distribution is skewed to the low values, while the MEA score distribution is closer to normal distribution. MEA and LMA show moderate Pearson correlations for all samples: r = 0.54, p < 0.001 for the joint sample, r = 0.52 for the Russian sample, and r = 0.66 for the Chinese sample. Section title: Descriptive statistics Educational score: 1.5471158027648926 Domain: other Document type: Study Language: en Table 4 represents the difference in scores between Russian and Chinese schoolchildren. Overall, Russian schoolchildren show significantly higher scores for AMAS and both subscales than Chinese schoolchildren . Section title: Descriptive statistics Educational score: 2.0731847286224365 Domain: other Document type: Study Language: en Supplementary Table 5 represents the difference in AMAS, LMA, and MEA scores between two samples for different age groups: 10–11-year-olds, 12–13-year-olds, and 14–15-year-olds. The same pattern is observed: Chinese schoolchildren demonstrate lower math anxiety in all three age groups than Russian schoolchildren. There is an exception for the LMA subscale for the oldest age group, where Chinese schoolchildren show a higher mean score . However, the effect size is relatively small, and statistical significance is subthreshold ( p = 0.014). Section title: Age differences Educational score: 2.8989267349243164 Domain: biomedical Document type: Study Language: en Supplementary Tables 6, 7 present age differences in AMAS scores for the two samples. Notably, no significant differences in total AMAS scores are observed across age groups in the Russian sample. However, when LMA and MEA scores are analyzed separately, opposite trends emerge: LMA scores decrease between the ages of 12–13 and 14–15, while MEA scores increase with age, particularly between the ages of 10–11 and 12–13. In contrast, in the Chinese sample, both MEA and LMA scores, as well as total AMAS scores, increase significantly with age. Section title: Age differences Educational score: 1.9114562273025513 Domain: biomedical Document type: Study Language: en Due to these opposing trends in LMA scores between the Russian and Chinese samples, Chinese schoolchildren in the 14–15-year-old cohort surpass their Russian peers in mean LMA scores. Supplementary Figure 6 illustrates the age differences in AMAS, LMA, and MEA scores between Russian and Chinese schoolchildren. Section title: Gender differences Educational score: 1.8262803554534912 Domain: biomedical Document type: Study Language: en Gender differences in the two samples are presented in Supplementary Table 8 and Supplementary Figure 7 . In both countries, girls demonstrate higher scores for AMAS and subscales. For LMA scales, the difference between boys and girls is not significant in the samples of both countries. However, the difference becomes significant in a joint sample. Section title: Differences in age-gender interaction Educational score: 2.0189929008483887 Domain: other Document type: Study Language: en Supplementary Tables 9, 10 and Supplementary Figure 8 provide information on the interaction between gender and age in the two samples. It can be seen that the youngest Russian schoolchildren (ages 10–11 years) demonstrate no significant differences in mean total and subscale scores. At age 10, Russian girls have slightly lower scores than boys on the AMAS, particularly on the MEA subscale (as indicated by intersecting confidence intervals). However, this gender advantage reverses at age 11. Section title: Differences in age-gender interaction Educational score: 1.5323172807693481 Domain: other Document type: Study Language: en For AMAS and MEA, a significant gender difference in Russian schoolchildren can be seen at age 12, and then on, its magnitude remains approximately the same. For LMA, no significant gender differences were observed across all ages. On the contrary, in Chinese schoolchildren, gender differences are significant from the beginning (10–11-year-olds). Interestingly, for LMA scores in 10–11-year-olds, there is a significant gender difference (girls score higher), but it disappears in schoolchildren of older ages. Overall, gender differences in AMAS and MEA scores are more significant in the Russian sample. Section title: Discussion Educational score: 1.713638424873352 Domain: other Document type: Study Language: en The study aimed to investigate differences in math anxiety scores between Russian and Chinese schoolchildren aged 10–15 years. Gender and age differences were estimated, as well as differences in gender-age interaction. The abbreviated Math Anxiety Scale was used as a measuring tool. Section title: Discussion Educational score: 2.213695526123047 Domain: other Document type: Study Language: en The bi-factor model fits the data best for both Russian and Chinese samples, and it has the lowest RMSEA, lowest SRMR, and highest TLI among all the models tested. A number of studies report the best fit of the bi-factor model as well. Some studies, however, report two-factor and second-factor models that fit the data best. One of the advantages of a bifactor model is that it simultaneously captures the general factor and separate factors for subscales . In the case of AMAS, the bifactor model shows that it makes sense to calculate total math anxiety scores and scores for LMA and MEA separately. Section title: Discussion Educational score: 1.2999584674835205 Domain: other Document type: Study Language: en It was also shown that there is an invariance across countries (i.e., AMAS measures the same construct in Russian and Chinese schoolchildren), which is consistent with previous studies on culture invariance . In both countries, AMAS demonstrates high internal consistency. However, LMA shows a slightly lower internal consistency for Chinese schoolchildren than the Russian subsample. It may be because the LMA subscale does not capture the specificity of math learning situations in China well. Section title: Discussion Educational score: 1.2354943752288818 Domain: other Document type: Study Language: en Schoolchildren from both countries demonstrate a similar pattern: low level of learning math anxiety and moderate level of math evaluation anxiety. This pattern is consistent with other studies . Overall, Russian schoolchildren show higher math anxiety in comparison with their Chinese peers. This tendency persists if comparison is made within age groups with one exception: 14–15-year-old Chinese children show higher levels of learning math anxiety in comparison with 14–15-year-old Russian children. The analysis of changes in math anxiety levels as a function of age reveals that in Russia, learning math anxiety decreases with age, while math evaluation anxiety increases, whereas in China, both learning and evaluation anxiety increase as children grow older. Section title: Discussion Educational score: 1.1026396751403809 Domain: other Document type: Other Language: en The differing trajectories of learning math anxiety dynamics in Russia and China explain the atypical pattern observed at ages 14–15. Section title: Discussion Educational score: 1.09046471118927 Domain: other Document type: Study Language: en Lanfaloni et al. demonstrate that learning math anxiety and math evaluation anxiety, despite being correlated, can exist independently and play different roles in math achievement. The difference in the dynamic of math evaluation anxiety and learning math anxiety observed in the Russian sample is partly consistent with a finding that secondary schoolchildren show higher math evaluation anxiety and similar learning math anxiety to primary schoolchildren . However, some studies show that overall math anxiety increases with age, which is more consistent with our findings for the Chinese sample . Further studies are necessary to understand the origins of different dynamics of learning math anxiety in China and Russia. Section title: Discussion Educational score: 1.2119925022125244 Domain: other Document type: Study Language: en In both countries, girls show significantly higher levels of math anxiety in comparison with boys on the entire scale and MEA subscale, while for LMA, no significant gender differences are observed. Notably, country differences are more pronounced than gender differences. In previous studies on Chinese , Russian , and other populations, gender differences in math anxiety were also highlighted. Section title: Discussion Educational score: 1.3981692790985107 Domain: other Document type: Study Language: en While investigating the changes in math anxiety with age for boys and girls separately (gender-age interaction), some differences between Russian and Chinese schoolchildren were observed. In Russia, there are no significant gender differences in the youngest age group, which is consistent with studies that demonstrate the absence of gender differences in primary schoolchildren . It is worth noting that at age 10 years, Russian girls demonstrate even lower levels of overall math anxiety and evaluation math anxiety, although the difference was not statistically significant. At age 12 years, boys demonstrate a low level of math anxiety, and this pattern is maintained in older ages. In China, that pattern was established earlier: girls score higher than boys in all ages observed in the current study. Section title: Discussion Educational score: 1.096970558166504 Domain: other Document type: Other Language: en The gender advantage reversal between 10 and 11-year-olds in Russian schoolchildren may be associated with a transition from primary to secondary school. However, further investigations are needed to understand the mechanism of such a rapid change. In general, differences between Russian and Chinese schoolchildren may be attributed to extremely high academic pressure on Chinese schoolchildren . Gender stereotypes also may play a role . Section title: Discussion Educational score: 1.816275715827942 Domain: other Document type: Study Language: en Some limitations have to be acknowledged. First, a study was cross-sectional in design, whereas a longitudinal sample is more applicable for tracing trajectories of math anxiety development with age. Second, despite similar oldest and youngest ages of schoolchildren, Russian and Chinese samples differ in terms of age structure. In particular, 10–11-year-old children are underrepresented in the Russian sample, whereas 14–15-year-old children are underrepresented in the Chinese sample. Section title: Discussion Educational score: 1.6985646486282349 Domain: biomedical Document type: Other Language: en In future studies, it is important to replicate the analysis in age-balanced samples and enhance the age range to cover all years of schooling. | Other | other | en | 0.999997 |
PMC11697701 | Section title: Introduction Educational score: 4.279776573181152 Domain: biomedical Document type: Review Language: en As the life expectancy of the global population gradually increases with the advancement of medical treatment and the improvement of living standards, the problem of population aging is becoming increasingly serious, and how to face population aging positively has become the most important medical and social issue in the world ( 1 ). One of the major challenges facing an aging population is the increasing prevalence of age-related frailty, which is a state of reduced ability to cope with stimuli due to age-related declines in the physiological reserve capacity and function of multiple systems and organs ( 2 ). Several prospective cohort studies have shown that frailty is strongly associated with poor health and that frail older people are more likely to experience death ( 3 ), disability ( 4–6 ), falls ( 7 ), and hospitalization ( 2 ) than non-frail older adults. Although frailty poses a significant risk of adverse health outcomes in older adults, it is a dynamic and reversible disease, which means that it is preventable and controllable and that early recognition and interventions of frailty can halt its progression ( 2 , 8 ). Early identification and diagnosis of frailty will help to maximize the reversal of its further progression, alleviate or delay underlying symptoms, control adverse clinical health outcomes such as recurrent hospitalization and death, maintain their functional status, and enhance their quality of life. Several studies have shown that timely recognition and intervention of frailty in the clinical setting or daily life can contribute to benefits for older adults ( 9 , 10 ), and may even delay the onset of death in 3 to 5% of older adults ( 11 ). Clinical practice guidelines developed by the International Conference of Frailty and Sarcopenia Research (ICFSR) also recommend that adults 65 years old and older should be screened for frailty using a simple, validated, and rapid screening tool appropriate for the specific scenario and that all older adults considered to be frail or pre-frail should be further assessed for frailty ( 12 ). However, there are no standardized criteria regarding the selection of screening and assessment tools for frailty. Therefore, the development of efficient and practical screening and assessment tools for frailty should be a top priority in the field of frailty research. This paper provides an overview of the current state of research on screening and assessment tools for age-related frailty and the characteristics of commonly used frailty scales, with the aim of helping clinical researchers and practitioners to accurately judge and fine-tune the management of frail older adults. Section title: Methodology Educational score: 4.118910789489746 Domain: biomedical Document type: Study Language: en The search database was PubMed. The retrieval time node ranged from January 2000 to December 2023. The retrieval strategy was optimized with the use of Boolean logical operators. The retrieval formula is ((“Frailty/diagnosis”[Mesh] OR “Frailty/epidemiology”[Mesh]) OR ((Frailties[Title/Abstract]) OR (Frailness[Title/Abstract])OR (Frailty Syndrome[Title/Abstract]) OR (Debility[Title/Abstract]) OR (Debilities[Title/Abstract]))) AND (). Then, we imported the transcript of all retrieved literature into Endnote Application. After briefly reading the title and abstract, articles not related to the screening or assessment of frailty were excluded. The specific inclusion criteria were defined as follows: (1) papers covered a population of older adults aged ≥60 years; (2) the paper’s main topic was screening and assessment of frailty; (3) the full text was accessible; (4) paper was presented in English. The exclusion criterion was that the paper was on the pathogenesis or interventions for frailty or its association with other diseases. The process of screening the literature was done independently by two researchers, followed by cross-checking. In case of disagreement between the two researchers, a third person was consulted to assist in the judgment. Next, we read the remaining literature and used an Excel sheet to record the screening or assessment scales addressed in each paper, selecting those that appeared ≥150 times. Finally, we read the literature pertaining to the above scales carefully and used another Excel sheet to document the content, focus, measurement patterns, and application scenarios of each scale for subsequent categorization and summarization. Section title: Current status of research on screening and assessment tools for frailty Educational score: 4.329472541809082 Domain: biomedical Document type: Review Language: en At present, studies on screening and assessment tools for frailty have mostly focused on two areas: frailty-related biological markers and frailty-related scales. The development of frailty involves multiple complex pathophysiological processes such as chronic inflammatory responses, imbalances in energy metabolism, nutritional deficiencies, immune disorders, oxidative stress, and so on ( 13 ). In older frail patients, the levels of biological factors involved in these pathophysiologic processes are altered accordingly and can be biomarkers of frailty. To date, biomarkers of age-related frailty can be categorized as inflammatory response-related biomarkers (C-reactive protein, interleukin-6, tumor necrosis factor) ( 14–17 ), metabolism-related biomarkers (muscle growth inhibitor, 25-hydroxyvitamin D, insulin-like growth factor 1) ( 18–21 ), immune-related biomarkers (neutrophils/lymphocytes ratio, platelet/lymphocyte ratio and systemic immune-inflammatory index) ( 22 ), Oxidative stress-related biomarkers (8-dihydro-2′-eoxyguanosine, reactive oxygen species, and superoxide dismutase) ( 23 , 24 ), and nutrient-related biomarkers (docosahexaenoic acid and vitamin B12) ( 25 , 26 ). However, biomarkers are susceptible to a variety of factors, making these indicators potentially less stable. For example, the circulating level of insulin-like growth factor 1 can be affected by nutritional levels and genetic factors, and the ratio of neutrophil/lymphocyte is susceptible to factors such as acute illnesses and infections. In addition, some frailty biomarkers have gender specificity, such as C-reactive protein, interleukin-6, and muscle growth inhibitors, which makes it necessary to take gender into account when selecting biomarkers. Therefore, although the changes in biomarkers precede the appearance of the organism’s phenotype, and the objectivity and sensitivity of biomarkers are superior, their specificity, precision, stability, and reliability are weaker than those of frailty-related scales ( 27 ). In fact, due to the lack of definitive laboratory tests and appropriate clinical testing techniques and equipment ( 28 ), the frailty-related scales have become the most commonly used clinical tool for the identification and assessment of frailty ( 29 ). Section title: Current status of research on screening and assessment tools for frailty Educational score: 4.549144744873047 Domain: biomedical Document type: Review Language: en The frailty scales are mostly based on the three conceptual models of frailty and are established by incorporating the clinical symptoms, signs and subjective feelings of the patient, which have the advantages of simplicity, time-saving, validity, economy and feasibility, such as: Fried Frailty Phenotype (FFP), Frailty Index (FI), Groningen Frailty Indicator (GFI), and so on. Three of the conceptual models described above are the Biological Phenotype, the Cumulative Health Deficit Model, and the Frailty Integral Model. In 2001, Fried et al. ( 30 ) proposed the concept of the Fried Frailty Phenotype (FFP) based on the theory of the Biological Phenotype, stating that frailty is a syndrome that meets three or more of the five phenotypic criteria, which is mostly centered on physical deterioration, together with a decrease in physical performance and muscular strength. The Cumulative Health Deficit Model suggests that the more health deficits are accumulated, the more severe the degree of frailty. Based on the Cumulative Health Deficit Model, Rockwood et al. ( 31 ) proposed the concept of the Frailty Index (FI) in 2005, which considered frailty as a complex unity of physiological, psychological, and social functioning, and a risk condition that develops as a result of the accumulation of multiple disorders due to multiple factors. The above two models are commonly used in existing studies and have been generally confirmed. Based on these two models, Gobbens et al. ( 32 ) proposed the Integral Model of Frailty (IMF), which further defines the operational definition of frailty as a dynamic and continuous process that includes somatic, psychological, and social aspects. Recently, WHO has proposed a new concept of “intrinsic capacity” based on healthy aging, which emphasizes the physiological and psychological dimensions of the individual, and is a longitudinal assessment that follows a trajectory rather than the traditional assessment of frailty at a cross-section or cut-off point. In a sense, intrinsic capacity evolves from frailty, and frailty is one of the components of the decline trajectory of intrinsic capacity ( 33 ). Another hybrid concept analysis of frailty described frailty as a dynamic and fluctuating inability to manage biopsychosocial and environmental stimuli that involves a decline in functioning and life changes, leading to a loss of autonomy and motivation, or poor health outcomes ( 34 ). Based on the above concepts, the frailty scales should address multiple dimensions such as somatic, psychological as well as social conditions. Frailty scales can be categorized as screening scales and assessment scales, and the two are often conflated in clinical practice. In fact, screening tools are not identical to assessment tools, and the emphasis of the two is not the same. The frailty screening scales focus on their operationalization, efficiency, and high sensitivity in order to screen older patients at risk of frailty or in a stage of frailty in a very short period of time, while the frailty assessment scales is more complex, focusing on high precision and support by reasonable biological indicators in order to determine more precisely the stage of frailty in which they are placed, and then to develop different treatment plannings according to their stages and risks ( 35 ). Section title: Current status of research on screening and assessment tools for frailty Educational score: 4.0439276695251465 Domain: biomedical Document type: Review Language: en Besides, the different screening and assessment tools count the different prevalence rates of frailty ( 36 ). A Meta-analysis showed that the prevalence of frailty within the same group was 12% using the FFP versus 24% using the FI ( 37 ). Another cross-sectional study among older Brazilians showed that the prevalence of frailty was 0.3% when assessed only in the physical domain of the Tilburg Frailty Indicator (TFI), 2.9% when assessed in both the physical and social domains, and 52% when assessed in a combination of all three domains: physical, social and psychological ( 38 ). Although a variety of geriatric frailty scales have been developed, there is still no recognized gold scale for assessing geriatric frailty, and translation from research to clinical practice remains a challenge in the future ( 39 ).Next, this article summarizes and analyzes the existing commonly used frailty scales in terms of their screening and assessment roles, and classifies each scale according to its content, focus, measurement mode, and application scenarios, so that clinicians or researchers can use the most appropriate frailty scales according to their characteristics, thus achieving the goal of early screening, early assessment, and early intervention of frailty, and reducing a series of adverse outcomes. Section title: Screening scales for age-related frailty Educational score: 3.396794557571411 Domain: biomedical Document type: Review Language: en The purpose of frailty screening is primarily to make a quick diagnosis, which is performed in all groups of older people, to identify those who are at high risk of frailty or already in a state of frailty through the use of simple tests. Here, we summarize and generalize the advantages and disadvantages of some commonly used screening scales for age-related frailty. Section title: Frail scale (FS) Educational score: 4.224903106689453 Domain: biomedical Document type: Review Language: en The FS is a clinically applicable self-screening scale for frail older adults proposed by the experts of the International Academy on Nutrition and Aging (IANA) ( 40 ). FS is a simple patient self-reported questionnaire containing only 5 items as follows: fatigue, increased sense of resistance, decreased activity, multimorbidity co-morbidity, and weight loss. It quickly categorizes the state of an older person into 3 types, among which those who meet 3 or more items are frail, those who meet 1 to 2 items are pre-frail, and those who do not have any of the 1 items are in a healthy state ( 41 ). FS can be easily mastered by healthcare professionals and has a high degree of maneuverability and screening efficacy, which has been translated into many languages and widely used worldwide ( 42–44 ). In addition, FS has high specificity and sensitivity. A survey of the Chinese version of the adaptation of FS among 1,235 Chinese community-dwelling older adults showed that the sensitivity of FS was as high as 86.96% while the specificity was as high as 85.64% ( 42 ). Another study, which conducted on 308 Chinese older patients aged 60 years and above, showed that FS had a sensitivity of 85.9% and a specificity of 72.5%, and noted that FS was convenient and time-saving, which could be used for the initial screening of frail patients to improve work efficiency ( 45 ). A cross-sectional study conducted by Aprahamian et al. ( 46 ) in a geriatric outpatient clinic showed that the sensitivity of FS was 54% and the specificity was 73% and suggested that FS could be selected as a screening tool for frailty because of its significant time and cost benefits. FS can be used not only to screen for frailty but also to predict adverse outcomes in older adults. FS is a valid predictor of mortality in older adults over 10 years, according to a cohort study among older adults aged 65 years and older ( 47 ). In a longitudinal study of women’s health in middle age in Australia, FS predicted the incidence of disability in women from middle age to old age over the next 15 years ( 48 ). Section title: Frail scale (FS) Educational score: 3.640976905822754 Domain: biomedical Document type: Review Language: en FS is entirely self-reported, without any objective measures, and can even be completed by telephone without face-to-face inspection, which makes it simple and easy to administer ( 49 ). The simplicity and ease of FS increases the convenience and completion rate of frailty screening, reduces the cost of screening, helps to carry out the development of frailty review, and is worthy of clinical application. However, FS suffers from a certain amount of information bias due to its complete reliance on patient self-reported outcomes, and special attention should be paid to this point in clinical applications. Section title: Clinical Frailty scale (CFS) Educational score: 4.230344772338867 Domain: biomedical Document type: Study Language: en The CFS is a frailty screening tool developed in 2005 by Rockwood et al. ( 31 ) for use in the Canadian Health and Aging Study. The original CFS contained 4 dimensions: physical activity, mobility, physical function, and energy status, which categorized older adults’ health status into 7 levels. With further research on geriatric frailty, the scope of CFS was expanded to co-morbidities, functional status, and cognitive ability domains, increasing the classification to 9 ( 50 ). The specific levels of CFS are as follows: Very Fit, Fit, Managing Well, Living with Very Mild Frailty, Living with Mild Frailty, Living with Moderate Frailty, Living with Severe Frailty, Living with Very Severe Frailty, and Terminally Ill, wherein levels 5 and above are defined exactly as a frailty state. A follow-up study of 210 acutely hospitalized older patients with adverse health outcomes found that both CFS and FS could identify older adults at risk for hospitalized adverse health outcomes and could be used as an easy screening tool for frailty; however, CFS demonstrated higher sensitivity than FS (89.6% vs. 54.6%) ( 51 ). Another cross-sectional study conducted in China also confirmed that the sensitivity of CFS was superior to FS as a screening tool for age-related frailty, both in all patients (94.1% vs. 63.0%) and in patients from different wards (91.8–98.5% vs. 58.0–65.7%) ( 52 ). In their study of the association between CFS and in-hospital mortality in patients with Corona Virus Disease 2019 (COVID-19), Sablerolles et al. ( 53 ) found that the in-hospital mortality was significantly higher in frailty patients (CFS 6–9) than in healthy patients (CFS 1–3) and that the grade of CFS was negatively correlated with the health status of the patient. A meta-analysis indicated that CFS could predict in-hospital mortality in acutely ill older patients and is a reliable predictor of short-term mortality in older patients presenting to the emergency department ( 54 ). Section title: Clinical Frailty scale (CFS) Educational score: 4.0341291427612305 Domain: biomedical Document type: Review Language: en CFS combines clinical judgment with objective measures and can be used not only to predict the need for institutional care or the incidence of death, but also to assess specific domains including co-morbidities, functioning, and cognition, making it a widely used screening tool for frailty ( 55 ). Because of its simplicity, rapidity, and accurate ability to predict adverse outcomes, CFS is often considered the most desirable tool for geriatric frailty screening in emergency medicine ( 56 ). In addition, CFS is highly sensitive to symptoms associated with frailty syndrome, which makes it also useful for assessing and stratifying the management of frailty ( 57 ). However, the completion of CFS needs to be based on clinical diagnosis combined with the interpretation of clinical parameters, which requires that the user should be a medical staff with a certain medical knowledge base, which limits the popularization and application of CFS to a certain extent. Section title: Edmonton Frailty scale (EFS) Educational score: 4.329390048980713 Domain: biomedical Document type: Study Language: en The EFS is a multidimensional screening scale for frailty developed by ROLFSON et al. ( 58 ) for non-specialists without specialized training in geriatrics based on the traditional frailty phenotype. The EFS consists of 9 dimensions and 11 entries as follows: (1) Cognitive function (unable to complete the clock drawing test successfully); (2) Functional performance (needing help from others in daily activities); (3) General health (self-assessment of health and the number of hospitalizations in the last year); (4) Independence (unable to complete manual labor alone, unable to walk 2 flights of stairs or walk 1,000 m); (5) Social support (unable to seek outside support successfully when encountering problems); (6) Medication status (being on 5 or more prescription medications at the same time, forgetting to take medication); (7) Mental status (depression); (8) Nutritional aspects (unintentional and significant weight loss recently); (9) Self-control (urinary and fecal incontinence). The EFS has a maximum score of 17, with a score of 0 to 4 indicating no frailty, 5 to 6 indicating sensitive individuals prone to frailty, 7 to 8 indicating mild frailty, 9 to 10 indicating moderate frailty, and 11 or more indicating severe frailty. EFS covers all domains of frailty and is highly correlated with other frailty scales ( 59 ). A study of the differences in the prevalence of frailty calculated by five frailty screening tools showed that the prevalence of frailty screened by the EFS was 25.2%, which was most similar to the prevalence of frailty of 27.6% after integrating the five frailty screening tools mentioned above, suggesting that the accuracy of EFS screening was high ( 52 ). In addition, the above study found that the EFS had the highest specificity for the assessment of frailty in surgical wards at 98.1%. EFS is commonly used in the identification of geriatric frailty prior to surgery and helps to stratify the risks and identify potentially modifying factors, which makes it have a higher feasibility rating in the surgical setting ( 60 ). A prospective study in people aged 70 years and older undergoing major abdominal surgery showed that the EFS has good reliability and validity and can be used as a preoperative assessment tool to predict the risk of surgical complications in older adults ( 61 ). In a study conducted by McIsaac et al. ( 62 ), it was found that although the accuracy of assessments of postoperative risks using the modified Fried Index (mFI) and the EFS was similar, the EFS had the advantage of a shorter time-consuming and greater patient acceptance, and should be recommended for clinical use. Section title: Edmonton Frailty scale (EFS) Educational score: 3.4313645362854004 Domain: biomedical Document type: Other Language: en EFS can be completed within 5 min, with high acceptance by both investigators and respondents. It is easy to operate and can be used by professionals or even non-professionals in multiple departments. It has a wide range of applications venues, which can be used in medical settings such as emergency, outpatient, and hospital wards, as well as in non-medical settings such as the community and the home, making it a reliable screening tool for geriatric frailty ( 63 ). However, EFS uses only one question to assess the specifics of the social support domain, disputing the comprehensiveness of the social frailty screen. Section title: Fried Frailty phenotype (FFP) Educational score: 4.2656731605529785 Domain: biomedical Document type: Study Language: en FFP is a phenotype derived by Fried et al. ( 30 ) from observing and tracking the follow-up to validate adverse outcomes in 5317 older adults aged 65 years or older who participated in the U.S. Longitudinal Cardiovascular Health Study, which explains why FFP was also called the Cardiovascular Health Study Index (CHS). The entries of FFP consist of 5 self-reported symptoms combined with biologically measured signs. The details of its entries are as follows: significant loss of body mass (unintentional weight loss of more than 4.5 kg or more in the past 1 year), weakness (low grip strength in both hands), fatigue (self-reported to be more easily fatigued in the last 6 months), slowness of the body (significant slowing of the walking speed), and physical inactivity (sedentary and physically inactive). Among them, those who fulfill 3 or more are defined as frail, those who have 1 or 2 are defined as pre-frail, and those who do not have any of the above 5 are defined as non-frail. FFP can not only measure the physical frailty status of older adults but also reflect the mental health status of the older adults and obtain more objective and accurate data, which is the most popular and widely used frailty measurement tool in the clinic ( 12 ). Results of a survey conducted among cancer patients showed that FFP had a sensitivity of 92% and a specificity of 41% for screening for frailty ( 64 ). FFP is widely applicable and its reliability and validity have been validated many times ( 65 ). FFP has now been shown to have predictive value for adverse health outcomes in a diverse range of older adults, including hospitalized and general older adults ( 66 ). Section title: Fried Frailty phenotype (FFP) Educational score: 3.9789023399353027 Domain: biomedical Document type: Study Language: en FFP is excellent for initial stratification for risks of the older population based on different characteristics (i.e., robust, pre-frail, and frail), without the need for an initial clinical assessment, and can be applied at the first patient contact ( 67 ). However, FFP focuses on the physiological level of assessment, lacks social, psychological, environmental, and multiple disease factors, and the implementation of some items (e.g., grip strength, step speed, etc.) requires trained personnel and specialized tools ( 68 ). The characteristics of FFP described above make it inappropriate for older adults with cognitive impairment, psychiatric disorders, impaired functioning, or in the acute phase of illness, which also make its applicability limited to hospitals, communities, and nursing facilities. In addition, the 5 phenotypic criteria of frailty allow for different ways of measuring them, and many previous studies have adapted their measurements, which have been confirmed to lead to differences in measurement effects ( 69 ). Therefore, future studies should report all the details about how the phenotypic criteria of frailty are measured in order to facilitate the interpretation of the results. Section title: Other common screening scales for frailty Educational score: 3.942030429840088 Domain: biomedical Document type: Review Language: en In recent years, more and more frailty screening tools have been developed as a result of the progress of frailty research. For example, in 2007 Ensrud et al. ( 70 ) found that data collected using the Study of Osteoporotic Fractures (SOF) Index was independently associated with FFP-predicted frailty-related adverse health outcomes, and subsequently, the SOF index became one of the screening tools for frailty; the Kihon Checklist (KCL) was proposed by the Japanese government for the implementation of the long-term care insurance system ( 71 ); and the Simple Self-Assessment Screening Tool—the Vulnerable Elders Survey-13 (VES-13) was created by Saliba et al. ( 72 ). The characteristics of common frailty screening scales are summarized in Table 1 and compared from nine perspectives, including entries, time required, content, and so on ( 30 , 31 , 40 , 58 , 70–76 ). Section title: Assessment scales for age-related frailty Educational score: 3.86953067779541 Domain: biomedical Document type: Review Language: en Rapid screening should be followed by further precise assessment of all older adults in pre-frail and frail states. An accurate assessment to evaluate which state of frailty a frail older adult is in can help to predict poor health outcomes better and facilitate the development of individualized treatment and management plans for frailty patients. Recently, there have been a large number of studies devoted to the development of objective quantitative frailty assessment tools ( 77 ). Since these assessment tools are not limited to questionnaires and there are differences in the consistency of the assessment tools, places of application, populations administered, and dimensions assessed, the results of the assessment of frailty cannot yet be judged uniformly. Therefore, we will next summarize the characteristics of the commonly used assessment scales for age-related frailty. Section title: Frailty index (FI) Educational score: 4.306675910949707 Domain: biomedical Document type: Review Language: en FI is a classic tool for assessing frailty in older adults developed by Mitnitski et al. ( 78 ) based on the cumulative deficit model. It covers multiple dimensions such as physical, psychology, cognition, and social functioning, and contains 30 to 70 evaluation items, the specific content of which is variable. Since there are no standardized criteria for the content of its items, researchers can choose their own entries according to their own research purposes. Although FI lacks specific variables that are uniformly standardized, the stability of FI is supported by the fact that FI consisting of different numbers and types of deficient items yields similar assessment results in different populations or research settings. Generally speaking, when FI ≥ 0.25, it implies frailty; when FI < 0.12, it implies non-frailty; when FI is between 0.12 and 0.25, it implies that the older adults are in the pre-frail stage ( 79 ). The sensitivity and specificity of FI in identifying frailty was 94.8 and 87.0% in all patients, 96.4 and 88.8% in patients on the cardiology ward, 95.9 and 81.1% in patients on the non-surgical ward and were 89.6 and 89.5% on the surgical ward ( 52 ). FI can be used not only for the screening of debilitation but also for the assessment of debilitation. FI is the first tool to successfully quantify the frailty state of older adults and has been widely used in several countries due to its good reliability and validity ( 80 ). FI is strongly associated with negative health-related outcomes (including mortality) and with deterioration in disease-specific health status, which makes it a good predictor of clinical prognosis ( 81 , 82 ). It has been found that FI can be utilized to evaluate the role of musculoskeletal disorders on frailty, rather than just being a categorical variable ( 83 ). In addition, FI has important applications in reflecting health service needs, public health management, and interventions. During the period of the COVID-19 pandemic, the use of an electronic version of the FI to assess frailty helped clinicians make decisions by identifying patients most likely to require ICU (intensive care unit) admission and those with a poor prognosis ( 84 ). Section title: Frailty index (FI) Educational score: 3.878303289413452 Domain: biomedical Document type: Study Language: en By focusing on the cumulative number of individual health deficits and integrating multiple complex health information into a single indicator, FI breaks through the limitation of a single variable describing the functional status, and can better assess the overall health status of older adults. With its advantages of multidimensionality, continuity, and objectivity, FI is suitable for frailty assessment in almost all environments. However, the establishment of FI requires a large amount of clinical information, while obtaining a large amount of clinical information is laborious, extremely cumbersome, and time-consuming, which is a major challenge in the use of FI for the assessment of frailty. Section title: Comprehensive geriatric assessment (CGA) Educational score: 4.115451335906982 Domain: biomedical Document type: Review Language: en CGA was conceptualized for the development of a scientific rehabilitation training program for older adults in the 1940s by Marjory Warren ( 85 ). As the population ages, the application of CGA continues to extend and becomes a common method of assessing and treating older patients with frailty or loss of function ( 86 ). CGA focuses on comprehensive assessments of somatic function, cognitive function, psychology, and social/environmental factors in older adults, thereby identifying and quantifying the degree of frailty, and providing the basis for subsequent frailty intervention strategies and comprehensive care, which is conducive to the early reversal of frailty, the slowing down of the deterioration process of frailty, and the improvement of health outcomes ( 87 ). A systematic evaluation that included 22 studies involving 10,315 patients showed that patients in the group that took interventions based on CGA had a lower likelihood of death or worsening of their condition and a higher likelihood of cognitive improvement compared to the group that took conventional medical care ( 88 ). Lee et al. ( 87 ) found that a CGA-based intervention program for a frail population could potentially promote healthy aging in community-dwelling older adults, with sustained health benefits of up to 1 year for them. Mazya et al. ( 89 ) conducted a trial of dynamic geriatric assessment-frailty intervention, in which the control group of the study received conventional treatment and humanistic care while the intervention group received dynamic assessment by CGA and multidisciplinary team interventions (including medication adjustments, exercise, and dietary advice, etc.) in addition to conventional care. After the 24-month intervention, the proportion of patients in the intervention group who were pre-frail was significantly higher than in the control group, suggesting that more patients with chronic diseases or co-morbidities in the intervention group moved from frailty to pre-frailty or strong than that in the control group. With the help of CGA, a comprehensive and scientific assessment of frailty can be made and a personalized medical intervention plan for the older adults can be developed to slow down the process of frailty by healthcare professionals. Section title: Comprehensive geriatric assessment (CGA) Educational score: 3.892306089401245 Domain: biomedical Document type: Review Language: en CGA can accurately judge the health status of older adults, assess the degree or stage of frailty, identify its causes or triggers, and provide suggestions for its preventive or therapeutic measures, which can help in making risk stratification and clinical decisions for frailty. However, as the CGA is a multidimensional and interdisciplinary diagnostic and therapeutic process that emphasizes a multidimensional and comprehensive risk factor exploration and assessment, it requires a large amount of manpower, energy, and time, which is inconvenient in practice and is only applicable to the hospital healthcare environment ( 90 ). Furthermore, despite the fact that many studies have shown a large advantage of CGA for the assessment of frailty, most of these studies were conducted on small samples of older adults within a single institution or region, resulting in poor accuracy of the results of these studies, which still need to be further validated ( 91 ). Section title: Groningen Frailty Indicator (GFI) Educational score: 4.132030487060547 Domain: biomedical Document type: Study Language: en GFI is a widely used frailty screening tool developed by Steverink et al. ( 92 ) in 2001. The GFI consists of the physical dimension (mobility, multiple health problems, physical fatigue, vision and hearing), the psychological dimension (depressed mood and anxiety), the cognitive dimension (cognitive dysfunction), and the social dimension (emotional isolation), with a total of 15 entries. The 15 entries of the GFI are all dichotomous questions, with each score set at 0 or 1. Higher scores on the GFI indicate more severe frailty, with those scoring ≥4 diagnosed as moderately or severe frailty ( 93 ). A study comparing the ability of four frailty screening tools to predict frailty-related adverse outcomes showed that the sensitivity of the GFI in predicting the frailsty adverse outcomes of death and hospitalization was 76.2 and 63.9%, respectively, and the specificity was 42.1 and 50.3%, which suggests that the GFI has a higher sensitivity and a poorer specificity ( 94 ). When the Chinese version of the GFI was used to screen for pre-frailty and frailty in 350 Chinese community-dwelling older adults, it demonstrated good internal consistency, with a Cronbach’s alpha coefficient of 0.87, a re-test reliability of 0.87, and the concurrent validity between the GFI and the Fried frailty phenotype of 0.76. suggesting that the GFI is a reliable and valid tool for pre-frailty and frailty screening in community-dwelling older adults ( 95 ). In addition, GFI can accurately predict total healthcare costs for the following year and can help healthcare professionals allocate healthcare resources ( 96 ). Section title: Groningen Frailty Indicator (GFI) Educational score: 2.069398880004883 Domain: biomedical Document type: Other Language: en GFI has been widely used in many countries such as Germany, Italy, France, and so on, and it is suitable for use in different assessment environments, such as communities, nursing homes, and healthcare facilities ( 97 ). However, compared with other scales, GFI focuses more on physical indicators such as physical strength, functioning, and health status, and does not adequately take into account psychological, cognitive, and social aspects, which may make the results of the GFI assessment slightly less integrated and comprehensive. Section title: Other common assessment scales for frailty Educational score: 3.8996787071228027 Domain: biomedical Document type: Review Language: en As the prevalence of frailty increases, more and more frailty assessment tools are being developed to make individualized and precise interventions for frail patients. For example, the Comprehensive Frailty Assessment Instrument (CFAI), which was first included in environmental assessment, was developed ( 98 ) and the Rapid Geriatric Assessment (RGA), which improves on the cumbersome assessment process of the CGA, was also created ( 99 ). A comparison of various common frailty assessment scales is shown in Table 2 ( 78 , 86 , 92 , 98–101 ). Section title: Conclusion Educational score: 3.9428510665893555 Domain: biomedical Document type: Review Language: en Frailty is an emerging global health burden with significant implications for clinical practice and public health. With the rapid growth of an aging population, the prevalence of frailty increases year by year. Frailty is a dynamically changing clinical state, with the pre-frailty phase showing potential reversibility. The early recognition of frailty and appropriate interventions for it can help slow or even reverse the process of it and reduce the risk of adverse outcomes. In order to achieve “healthy aging” centered on wellness, we need to improve the rate of the early identification of frailty for its early precise intervention. Although there are approximately 67 screening and assessment tools for frailty internationally and and there is a trend toward an increase in the number of such tools ( 77 ), different screening and assessment tools have more significant differences in conceptual basis, clinical utility, program content, and place of application. As a result, there is still considerable debate as to what is the best scale for screening and assessing frailty. Section title: Conclusion Educational score: 3.9018185138702393 Domain: biomedical Document type: Review Language: en Strictly speaking, frailty screening scales and assessment scales have different requirements and should not be confused. Screening scales need to be simple, quick, and highly sensitive to frailty, which allows clinicians to recognize frailty quickly. Assessment scales require high accuracy, utility, and support of sound biological theories, which allows clinicians to identify the stages of frailty in older adults accurately and predict the occurrence of adverse health events in frail older adults, such as falls, cognitive deficits, loss of mobility, and death. Through reading a large amount of literature, we have differentiated and reviewed the most common frailty scales for screening and assessment in order to help researchers as well as healthcare professionals to select the most appropriate frailty scales for its identification and assessment. Based on our summaries and generalizations, we roughly design the process of screening and assessment for the frailty in different types of older people, which is shown in Figure 1 . The high-risk groups and older people without frailty symptoms are screened out through a rapid screening scale, and the high-risk groups should go to the hospital for treatment. Older people without frailty symptoms should adopt self-screening and regular community screening once every 6 months to prevent the emergence of frailty. For older hospitalized patients, high-risk groups are screened out through the doctor’s simple judgment (whether it needs to be evaluated directly), and then a detailed and comprehensive evaluation can make them quickly benefit from the follow-up personalized intervention treatment. Section title: Conclusion Educational score: 3.9630966186523438 Domain: biomedical Document type: Review Language: en The development of frailty can be slowed or even reversed by early recognition, accurate assessment, and timely interventions for frailty, which will reduce the strain of frailty on healthcare systems around the world and promote healthy aging of the global population. Although we have provided insights into potential solutions for early identification and assessment of frailty by reviewing a large body of literature, however, there are some limitations to our study. Firstly, we searched only one database and limited our search to one language, which may have led to the omission of relevant articles. Secondly, our review lacked a critical assessment of the included articles, which resulted in the variable quality of the articles we included. Finally, we only summarized scales that have been studied frequently and are relatively well-established, which is somewhat one-sided. In the future, we still need to explore objective, simple, time-saving, effective, economical, and feasible scales that can accurately identify and assess frailty in clinical practice. | Review | biomedical | en | 0.999997 |
PMC11697712 | Section title: Introduction Educational score: 3.2054429054260254 Domain: biomedical Document type: Study Language: en Antibiotics are extensively used in livestock production to prevent and treat diseases [ , , ]. In 2010, global antibiotic use in livestock production reached over 63 Gg . Approximately 30–90% of these antibiotics are excreted in an unchanged active form during livestock excrements . Annual antibiotic consumption in livestock production worldwide is projected to reach approximately 106 Gg by 2030 . This may increase the use of antibiotics in the environment from livestock production. Section title: Introduction Educational score: 3.2783350944519043 Domain: biomedical Document type: Study Language: en China requires a thorough evaluation of how livestock production impacts antibiotic pollution in rivers and groundwater. China is one of the largest global users of antibiotics in livestock production globally . The total use of antibiotics for livestock production was approximately 15 Gg in China in 2010 . This amount is twice that of the United States . This is because China had many more livestock species and hardly had regulations to control antibiotic use compared to the United States [ , , ]. Today, China still has a higher livestock population than countries such as the United States , which may lead to more antibiotic use. Manure management differs from the past. Historically, livestock manure has been used as an organic fertilizer, especially in crop production . Since the 1990s, large amounts of manure were not used in crop production . Synthetic fertilizers largely replaced manure. As a result, considerable amounts of manure were dumped into surface waters. Since the 2000s, the national government has introduced various environmental policies to avoid water pollution by directly discharging manure through more manure recycling on the land . Farmers start using manure more often as an organic fertilizer. Section title: Introduction Educational score: 3.3773915767669678 Domain: biomedical Document type: Study Language: en Because of the incomplete absorption and partial metabolism, unchanged active forms of antibiotics are excreted from the bodies of livestock species in the manure . Some amounts of antibiotics in manure can directly enter rivers through direct discharges of manure [ , , ]. In contrast, some antibiotics can enter agricultural land through manure application. From fertilized land, antibiotics can enter rivers through runoff and soil erosion and leach through deeper soil layers into groundwater . Antibiotics have been widely detected in soils and waters in China . Antibiotics in the environment can disturb biological and microbial communities and promote the transition and spread of antibiotic-resistant genes . Section title: Introduction Educational score: 2.748927354812622 Domain: biomedical Document type: Study Language: en A spatially explicit assessment of antibiotic inputs to rivers and groundwater from livestock does not exist for Chinese sub-basins. Meanwhile, our understanding of the contribution of different livestock species to antibiotic-related water pollution in rivers and groundwater remains limited. Previous studies have focused on specific sources, locations, antibiotics, and water systems . Many studies have reported the concentration of antibiotics in livestock farms, wastewater, or manure and have covered specific livestock farms or species . These studies provided important insights into local water pollution with antibiotics to better understand the local contributions of antibiotics and livestock species . Local stakeholders and decision-makers can use this information to develop policies and regulations. However, such insights are hardly available to cover the whole of China. Section title: Introduction Educational score: 3.926177740097046 Domain: biomedical Document type: Study Language: en Several models have been used to quantify antibiotics-related water pollution in China . For instance, a Level-III fugacity model is applied to China . This model allows for the spatially explicit analysis of 58 basins of China, which enables quantifying the contribution of livestock species to rivers in 2013 . This model does not quantify antibiotic leaching into groundwater or consider the diffusion of antibiotic inputs to rivers in 2020. The model only considers the antibiotic usage by pigs, chickens, and others (total weight of meat of sheep, cows, and fish) in China . River sub-basins are crucial for better understanding spatial variability in pollution levels, particularly in large basins like the Yellow and Yangtze Rivers. Existing models hardly focus on sub-basin scales for the whole of China. An exception is the family of the MARINA models (Model to Assess River Inputs of pollutaNts to seAs). These models run at the sub-basin scale for nutrients, plastics, and chemicals [ 10 , , , , ]. The models have been widely applied globally, nationally (China and Europe), and in individual lakes [ 10 , , , , , , ]. However, such models do not exist for antibiotics. Section title: Introduction Educational score: 3.0121817588806152 Domain: biomedical Document type: Study Language: en Many antibiotics are used in Chinese livestock production. Among them, 24 antibiotics are extensively used in livestock production and frequently detected in China . These 24 antibiotics are grouped into six categories, i.e., Sulfonamides, Tetracyclines, Fluoroquinolones, Macrolides, β-lactams, and Lincosamides . Antibiotics used for livestock production accounted for 52% of the total antibiotics in China in 2013 . Zhang et al. reported that these 24 antibiotics contributed to over 55% of the total usage of antibiotics in China in 2013 based on survey data. Section title: Introduction Educational score: 3.726142168045044 Domain: biomedical Document type: Study Language: en Thus, there is a lack of quantitative information at the sub-basin scale on the effects of livestock distribution and manure management on antibiotic water pollution in China. In recent decades, the Chinese government has exhibited increased proactivity and assertiveness in addressing diffuse source pollution caused by agriculture. Agricultural Green Development (AGD) was proposed as a national strategy for sustainable development in China at the 19th National People’s Congress in 2017 . AGD aims to increase environmental quality while satisfying food demand to achieve sustainable agriculture. However, to the best of our knowledge, we still lack knowledge on simultaneously assessing livestock production relocation, improving manure management, and the resulting impacts on antibiotic water pollution during the period of 2010–2020. The period from 2010 to 2020 is important when looking at the history of agricultural policies in China. Before 2010, agricultural policies for manure management were generally limited in China . From 2010 until 2020, various agricultural policies have been introduced to facilitate more manure recycling on land to avoid direct discharges of manure to rivers and, thus, reduce river pollution [ , , ]. Some policies aim to shift livestock production from the south to the north [ , , ]. Examples are the ‘14th Five-Year National Agricultural Green Development Plan’ , ‘Livestock and Poultry Manure Utilization Action Plan ’ , and China’s livestock relocation policies . These policies may influence water pollution with antibiotics in China. However, the period of 2010–2020 has not been well studied for water pollution with antibiotics but needed to support the formulation of water pollution control strategies to achieve AGD policies in China as well as to support the United Nations' Sustainable Development Goals 6 (clean water) and 12 (sustainable food production) . Sub-basin analyses may help better understand pollution hotspots and their sources to formulate sustainable AGD solutions for clean water in China and elsewhere. Section title: Introduction Educational score: 4.130053520202637 Domain: biomedical Document type: Study Language: en Our main research objective is to estimate the flow of 24 antibiotics from seven livestock species into rivers and leaching into groundwater in 395 sub-basins in China and to examine changes in antibiotic water pollution between 2010 and 2020. The spatially explicit MARINA-Antibiotics (China-1.0) model (Model to Assess River Inputs of pollutaNts to seAs for Antibiotics in freshwater) is developed and evaluated for this study. Our model results can be used to prioritize sub-basins, livestock species, and antibiotic groups in water pollution control. Other countries that experience antibiotic pollution from intensive livestock production can use our model as a tool to better understand which antibiotic group (e.g., Sulfonamides), where (sub-basins), and from which livestock species (e.g., cattle) enter rivers and groundwater. This could raise the attention of the public, policymakers, and other stakeholders on the need to consider antibiotics in national water quality policies and monitoring programs. This study will contribute to developing AGD strategies to reduce antibiotic use in Chinese waters and elsewhere. Section title: MARINA-antibiotics model Educational score: 4.03566837310791 Domain: biomedical Document type: Study Language: en MARINA-Antibiotics is short for Model to Assess River Inputs of pollutaNts to seAs for Antibiotics in freshwater. We developed the first version for antibiotic loadings into rivers and groundwater (via leaching) from livestock manure and applied it to 395 Chinese sub-basins. Our MARINA-Antibiotics (China-1.0) model was based on an existing sub-basin-scale MARINA-Multi (Global-2.0) modeling approach and integrated chemical approaches . Our model quantified antibiotics in rivers and groundwater using consistent model inputs (e.g., livestock density) in space (e.g., sub-basins) and time (e.g., annual). Our selection of the years 2010 and 2020 was justified for two primary reasons: (1) the implementation of key Chinese agricultural policies during this period [ , , , , , 42 ] and (2) the availability of data for these years (see details in Supplementary Materials). Thus, we applied the model to 2010 and 2020 to demonstrate the potential effect of the implemented national agricultural policies on water pollution with antibiotics in China. Fig. 1 Overview of the MARINA-Antibiotics (China-1.0) model, focusing on livestock manure. MARINA-Antibiotics is short for Model to Assess River Inputs of pollutaNts to seAs for Antibiotics in freshwater. The model considers seven livestock species: pigs, buffaloes, cattle, chickens, goats, sheep, and ducks. ‘A’ denotes antibiotics. Twenty-four antibiotics from six groups are considered in this model: Sulfonamides, Tetracyclines, Fluoroquinolones, Macrolides, β-lactams, and Lincosamides. For details on model inputs, see Tables S1–S4 in the Supplementary Materials. Sources: the MARINA-Antibiotics (China-1.0) model (Section 2.1 ). Fig. 1 Section title: MARINA-antibiotics model Educational score: 4.084633827209473 Domain: biomedical Document type: Study Language: en The MARINA-Antibiotics (China-1.0) model used a lumped approach to quantify annual antibiotic inputs to rivers and leaching to groundwater from seven livestock species. The livestock species included pigs, buffaloes, cattle, chickens, goats, sheep, and ducks. In our study, we selected 24 antibiotics from six main categories : (1) Sulfonamides (sulfaquinoxaline, sulfathiazole, sulfamethoxazole, sulfamethazine, sulfameter, sulfamonomethoxine, sulfaguanidine, sulfadiazine, and sulfachlorpyridazine); (2) Tetracyclines (oxytetracycline, doxycycline, tetracycline, and chlortetracycline); (3) Fluoroquinolones (pefloxacin, ofloxacin, norfloxacin, fleroxacin, enrofloxacin, difloxacin, and ciprofloxacin); (4) Macrolides (tylosin and roxithromycin); (5) β-lactams (penicillin-G); (6) Lincosamides (lincomycin). Section title: MARINA-antibiotics model Educational score: 3.168377637863159 Domain: biomedical Document type: Study Language: en We considered the direct discharge of manure to rivers, degradation (persistence) of antibiotics in manure during storage, soil degradation and adsorption of antibiotics, runoff, soil erosion, and leaching to determine the fate and transfer of antibiotics from livestock production to rivers and groundwater ( Fig. 1 , equations (1) , (2) , (3) , (4) , (5) , (6) , (7) , (8) , (9) ). The input data were processed using ArcGIS, and many model parameters differ among sub-basins (see Tables S1 and S9 in the Supplementary Materials for details). Section title: MARINA-antibiotics model Educational score: 4.156415939331055 Domain: biomedical Document type: Study Language: en Below, we presented calculations for the inputs of antibiotics to rivers and groundwater from livestock production. In the MARINA-Antibiotics (China-1.0) model, the top 60 cm of the soil was regarded as the root zone. The 60–200 cm region of the soil was considered the last soil layer before antibiotic leaching into groundwater, following the definition from Poggio et al. and Arrouays et al. . In the top 60 cm of the soil, antibiotics in soil particles and solutions could be transported to rivers via soil erosion and runoff. Below 200 cm of the soil, we estimated the antibiotics that remain in the soil solution after runoff losses, and these antibiotics could further leach into groundwater. The depth of 200 cm was chosen based on its relevance to the scope of the study. This depth captured both relevant processes in the soil profile and considered the potential vertical movement of antibiotics in deeper soil layers. In existing studies [ , , , , ], 200 cm was used as a common depth for examining soil properties, leaching patterns, and transport of pollutants. For example, Arrouays et al. indicated that 200 cm is pragmatic for soil sampling, providing reliable observations of soil properties, even in thick soil. For assessing pollutants leaching into groundwater, Zhang et al. explored the impacts of agricultural fertilization on nitrate in soil and leaching into groundwater, including the movement of agricultural nitrate to a depth of 200 cm. This depth also typically included the root zone of most crops (e.g., corn, wheat, alfalfa, and soybean) and reached the subsoil . Contaminants moving to this depth may potentially entered groundwater or deeper soils. Section title: Modeling inputs of antibiotics into rivers Educational score: 4.124126434326172 Domain: biomedical Document type: Study Language: en The model distinguished between diffuse and point sources of river pollution. The annual inputs of antibiotics into the rivers from point and diffuse sources were calculated using equation (1) . Point sources of antibiotics in rivers resulted from the direct discharges of livestock manure from storage systems (equation (2) ). Diffuse sources of antibiotics in rivers resulted from runoff and soil erosion after the application of manure to agricultural land, which is corrected for degradation processes in the soil. Antibiotic inputs to rivers from diffuse sources were calculated as a function of antibiotic inputs to agricultural land from storage and grazing systems, soil retention, erosion, and runoff (equations (3) , (4) , (5) , (6) , (7) , (8) ). (1) R S A , i , j = R S d i f A , i , j + R S p n t A , i , j (2) R S p n t A , i , j = S s s , A , i , j × f r d , i , j (3) R S d i f A , i , j = R S s r A , i , j + R S e s A , i , j (4) R S s r A , i , j = S s o l A , i , j × F E s r j (5) R S e s A , i , j = S p a r A , i , j × F E e s j Section title: Modeling inputs of antibiotics into rivers Educational score: 1.461828351020813 Domain: other Document type: Other Language: en In these equations, Section title: Modeling inputs of antibiotics into rivers Educational score: 1.9617860317230225 Domain: biomedical Document type: Other Language: en R S A , i , j is the total antibiotic ( A ) input to rivers ( RS ) from the manure of livestock species ( i ) in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 1.9996027946472168 Domain: biomedical Document type: Other Language: en R S d i f A , i , j is the antibiotic ( A ) input to rivers ( RS ) from the manure of livestock species ( i ) resulting from diffuse sources ( dif ) in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 1.969359278678894 Domain: biomedical Document type: Other Language: en R S p n t A , i , j is the antibiotic ( A ) input to rivers ( RS ) from the manure of livestock species ( i ) resulting from point sources ( pnt ) in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 2.6795997619628906 Domain: biomedical Document type: Study Language: en S s s , A , i , j is the excretion of the antibiotic ( A ) in the manure of livestock species ( i ) in the storage system ( ss ) in the sub-basin ( j ) (kg antibiotics per year). This parameter was calculated according to the equations in Table S1 of the Supplementary Materials. See more details in Tables S1–S4 of the Supplementary Materials. Section title: Modeling inputs of antibiotics into rivers Educational score: 1.4224156141281128 Domain: other Document type: Other Language: en f r d , i , j is the fraction ( fr ) of direct discharges ( d ) of manure to rivers from livestock species ( i ) in the sub-basin ( j ) (0–1). This fraction differs among livestock species. Section title: Modeling inputs of antibiotics into rivers Educational score: 1.8893731832504272 Domain: biomedical Document type: Other Language: en R S s r A , i , j is the antibiotic ( A ) inputs to rivers ( RS ) from the manure of livestock species ( i ) resulting from surface runoff ( sr ) in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 1.8425315618515015 Domain: biomedical Document type: Other Language: en R S e s A , i , j is the antibiotic ( A ) input to rivers ( RS ) from the manure of livestock species ( i ) resulting from soil erosion ( es ) in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 2.1979918479919434 Domain: biomedical Document type: Other Language: en S s o l A , i , j is the amount of antibiotic ( A ) from the manure of livestock species ( i ) available in the soil solution ( Ssol ) after adsorption and degradation in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 2.3064682483673096 Domain: biomedical Document type: Study Language: en F E s r j is the export fraction ( FE ) of antibiotics that entered rivers in the soil solution resulting from surface runoff ( sr ) in the sub-basin ( j ) (0–1). This export fraction was calculated as a function of surface runoff and precipitation different per sub-basin. Details on calculations are in Tables S1–S4 of the Supplementary Materials. Section title: Modeling inputs of antibiotics into rivers Educational score: 2.2753798961639404 Domain: biomedical Document type: Other Language: en S p a r A , i , j is the total amount of antibiotic ( A ) from the manure of livestock species ( i ) available in the soil particles ( Spar ) after adsorption and degradation in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 1.9828671216964722 Domain: biomedical Document type: Study Language: en F E e s j is the export fraction ( FE ) of antibiotics that enter rivers in the soil particles resulting from soil erosion ( es ) in the sub-basin ( j ) (0–1). This export fraction varied among sub-basins. More details are in Tables S1–S4 of the Supplementary Materials. Section title: Modeling inputs of antibiotics into rivers Educational score: 3.8470780849456787 Domain: biomedical Document type: Study Language: en Antibiotics in soil solution and soil particles after adsorption and degradation were calculated as a function of various processes (equations (6) , (7) ) as follows: (6) S p a r A , i , j = W S d i f A , i , j × F S p a r , A , j × F S d e , A , j (7) S s o l A , i , j = W S d i f A , i , j × F S s o l , A , j × F S d e , A , j where, Section title: Modeling inputs of antibiotics into rivers Educational score: 1.8574851751327515 Domain: biomedical Document type: Other Language: en W S d i f A , i , j is the application of antibiotic ( A ) from the manure of livestock species ( i ) in the sub-basin ( j ) to agricultural land (kg antibiotics per year). Section title: Modeling inputs of antibiotics into rivers Educational score: 3.0639569759368896 Domain: biomedical Document type: Study Language: en F S p a r , A , j and F S s o l , A , j are the adsorption fractions ( FS ) of antibiotic ( A ) in the soil particle ( par ) and solution ( sol ) in the sub-basin ( j ), respectively (0–1). The adsorption fractions of antibiotics were calculated as a function of the linear adsorption constant (K d value) of antibiotics (L kg −1 ) and the maximum water-holding capacity of soil based on the soil textures. The adsorption fractions of antibiotics in the soil particle and solution varied among sub-basins. Section title: Modeling inputs of antibiotics into rivers Educational score: 2.66865611076355 Domain: biomedical Document type: Study Language: en F S d e , A , j is the degradation ( de ) fraction ( FS ) of antibiotic ( A ) in the soil after manure application from the manure management systems. This fraction was calculated as a function of the degradation rate of antibiotics in the soil ( k j ) and the degradation time duration in the soil ( t j ). This degradation fraction differed among sub-basins. More details are in Tables S1–S4 of the Supplementary Materials. Section title: Modeling inputs of antibiotics into rivers Educational score: 4.1495680809021 Domain: biomedical Document type: Study Language: en Adsorption processes reflect the amount of antibiotics attached to soil particles and in solution. Physical (e.g., the maximum water-holding capacity of soil-related antibiotic adsorption) and chemical (e.g., Kd value, the linear adsorption constant) processes influence the adsorption of antibiotics in the soil. The maximum water-holding capacity of the soil depends on soil texture. Here, we distinguished the dominant soil textures among sub-basins based on the data from the National Earth System Science Data Center (NESSDC) . According to Pan and Chu and Geohring et al. , we considered the dominant maximum water-holding capacity based on soil textures among sub-basins. The degradation of antibiotics in the soil is influenced by physical (such as soil temperature and soil saturated water content, which relates to antibiotics degradation), chemical (such as soil pH, soil organic carbon content, and the half-life of antibiotics-related degradation), and biological (such as biological responses to soil changes associated with antibiotic degradation) processes. These processes were incorporated into our model according to the approach of Tang and Maggi and Wöhler et al. (details are in Tables S1–S4 of the Supplementary Materials). Each sub-basin has different model inputs to represent the physical, chemical, and biological processes in the soil for the degradation of antibiotics. Section title: Modeling inputs of antibiotics into rivers Educational score: 3.847972869873047 Domain: biomedical Document type: Study Language: en Antibiotic inputs to agricultural land from grazing and storage systems were calculated using equation (8) . Livestock manure was considered an organic fertilizer for agricultural land. In grazing systems, manure-containing antibiotics entered the land directly. For storage systems, the input of antibiotics to agricultural land was calculated as a function of manure production, livestock number, and the degradation (persistence) rates of antibiotics during the manure management practices (e.g., storage, composting, and anaerobic digestion) according to the livestock species and antibiotics. This implied that manure was collected during storage before being applied to agricultural land and was also corrected for direct discharges of manure to rivers. Antibiotic losses during storage were associated with, for example, the degradation of antibiotics during manure management practices in storage systems. (8) W S d i f A , i , j = W S d i f A , s g , i , j + W S d i f A , s s , i , j Section title: Modeling inputs of antibiotics into rivers Educational score: 1.4502360820770264 Domain: other Document type: Other Language: en In this equation, Section title: Modeling inputs of antibiotics into rivers Educational score: 2.0828192234039307 Domain: biomedical Document type: Study Language: en W S d i f A , s g , i , j is the application of antibiotic ( A ) to agricultural land from the manure of livestock species ( i ) from grazing system ( sg ) in sub-basin ( j ) (kg antibiotics per year). This parameter was calculated according to the equations in Table S1 of the Supplementary Materials. See more details in Tables S1–S4 of the Supplementary Materials. Section title: Modeling inputs of antibiotics into rivers Educational score: 3.372023105621338 Domain: biomedical Document type: Study Language: en W S d i f A , s s , i , j is the application of antibiotic ( A ) to agricultural land from the manure of livestock ( i ) from the storage system ( ss ) after correcting for the direct discharges of manure to rivers and manure management practices (e.g., storage, composting, and anaerobic digestion) in the sub-basin ( j ) (kg antibiotics per year). The model input was calculated using the following equation: W S d i f A , s s , i , j = S s s , A , i , j × ( 1 − f r d , i , j ) . See more details in Supplementary Materials Tables S1–S4 . Section title: Modeling leaching of antibiotics to groundwater Educational score: 2.9802591800689697 Domain: biomedical Document type: Study Language: en We listed the main equation that was used to calculate the amount of antibiotics leaching into groundwater from manure application on agricultural land (the amount of antibiotics leaving the soil layer below 200 cm): (9) G W A , i , j = ( S s o l A , i , j − R S s r A , i , j ) × f r l e , A , j where, Section title: Modeling leaching of antibiotics to groundwater Educational score: 2.081372022628784 Domain: biomedical Document type: Other Language: en G W A , i , j is the total input of antibiotic ( A ) leaching into groundwater ( GW ) from the manure application on agricultural land from livestock species ( i ) in the sub-basin ( j ) (kg antibiotics per year). Section title: Modeling leaching of antibiotics to groundwater Educational score: 2.8572256565093994 Domain: biomedical Document type: Study Language: en f r l e , A , j is the leaching fraction ( f r l e ) of the antibiotic ( A ) from the soil solution below 200 cm of soil in the sub-basin ( j ) (0–1). This fraction was calculated as a function of the soil texture, the antibiotics available in the soil solution, and the maximum water-holding capacity of the soil (details in Tables S1–S4 of the Supplementary Materials). This model input differed among sub-basins. Section title: Model inputs Educational score: 2.4332802295684814 Domain: biomedical Document type: Study Language: en Livestock numbers in 2010 were derived from Li et al. . We calculated the trends of the livestock number at the provincial level from 2010 and 2020 based on Chinese Statistic Yearbooks. The livestock numbers and their spatial distribution for 2010 and 2020 were derived using the following steps based on the approaches of Li et al. and Zhang et al. . We assigned the provincial changes in livestock numbers between 2010 and 2020 to corresponding 0.5-degree grids. Then, we multiplied the changes by the livestock number at 0.5-degree grids in 2010. We summed the values over the grids for the corresponding sub-basins to obtain the number of livestock with changed spatial distributions in 2020 per sub-basin. Livestock numbers differed among livestock species and sub-basins. See more details in Supplementary Materials Fig. S2 and Tables S1–S4 , and S9 . Section title: Model inputs Educational score: 2.8748319149017334 Domain: biomedical Document type: Study Language: en The fractions of direct discharges of livestock manure into rivers by livestock species in 2010 were derived from Li et al. . Due to data availability, we updated these fractions by livestock species in 2020 based on trends in manure not recycled to agricultural land derived at the provincial level by Zhu et al. to obtain input data at the sub-basin scale. We aggregated the provincial data to the sub-basin scale following the approaches of . The excretion rates of 24 antibiotics by livestock species were calculated based on previous studies (Supplementary Materials Table S3 ) [ 1 , , , , , 57 ]. This fraction differed among livestock species. See more details in Supplementary Materials Fig. S2 and Tables S1–S4 , and S9. Section title: Model inputs Educational score: 3.876465082168579 Domain: biomedical Document type: Study Language: en The export fraction of antibiotics that enter rivers in the soil solution due to surface runoff in the sub-basin in 2010 was derived from Li et al. . The Variable Infiltration Capacity hydrological model provided data for precipitation and natural river discharges for the period up to 2020 . Then, we calculated the average annual precipitation per sub-basin by statistically averaging 30-year annual runoff per sub-basin. This was calculated based on the 30-year average annual natural river discharge in the sub-basin divided by their drainage area. Finally, we calculated the export fraction in 2020 based on the 30-year averaged runoff divided by the 30-year averaged precipitation per sub-basin following the approach of Li et al. . See more details in Supplementary Materials Fig. S2 and Tables S1–S4 , and S9. This model parameter was different per sub-basin. This export fraction reflected land use change and pollutants transported from land to rivers through surface runoff. Sub-basins with higher export fractions received more pollutants entering their rivers through surface runoff than those with lower export fractions. Section title: Model evaluation approach Educational score: 2.76421856880188 Domain: biomedical Document type: Study Language: en We evaluated our model following the ‘building trust’ approach of Strokal et al. , which was developed for large-scale water quality models, and validation is challenging . We selected four options to build trust in the model approach, inputs, and outputs. Option 1 compared our model inputs with existing datasets. Option 2 compared our model outputs with those of existing studies. Here, we collected available data, including those from modeling studies and observations. Option 3 compared the spatial variability of pollution hotspots with existing studies. Option 4 used expert knowledge to verify uncertain model parameters for which data are limited in space and time. The results of these four options are presented in the Results and Discussion section. Section title: Definition of pollution hotspots Educational score: 3.9822309017181396 Domain: biomedical Document type: Study Language: en We defined ‘pollution hotspots’ for the antibiotic input into rivers and groundwater following the approach of Li et al. . In descending order, we ranked sub-basins based on the inputs of antibiotics per km 2 of the sub-basin areas. Consequently, we have inputs ranging from Level I (lower inputs) to Level V (higher inputs). For rivers, the input of antibiotics ranged from 0 to 0.2 g km −2 year −1 (Level I), 0.2–2 g km −2 year −1 (Level II), 2–32 g km −2 year −1 (Level III), 32 to 700 (Level IV), and 700 to 4468 (Level V). For groundwater, antibiotic inputs ranged from 0 to 0.1 g km −2 year −1 (Level I), 0.1–0.2 g km −2 year −1 (Level II), 0.2–2 g km −2 year −1 (Level III), 2–3 g km −2 year −1 (Level IV), and 3–31 g km −2 year −1 (Level V). The top 25% of sub-basins were considered pollution hotspots, for which inputs of antibiotics in rivers and groundwater fall under Levels IV and V. Section title: Antibiotic river pollution Educational score: 4.105098247528076 Domain: biomedical Document type: Study Language: en We modeled that approximately 8354 and 3424 tonnes of all 24 antibiotics entered Chinese rivers from livestock production in 2010 and 2020, respectively . This implies that the total input of antibiotics into rivers decreased by approximately 59% from 2010 to 2020 for China as a whole. This was largely due to decreased direct manure discharges into rivers (fewer manure point sources). In 2010, the contribution of direct manure discharges to the total input of antibiotics in all rivers in China was 8137 tonnes. This decreased to 3219 tonnes in 2020 (Supplementary Materials Tables S6–S9 ). The ‘14th Five-Year National Agricultural Green Development Plan’ has called for an increase in the use of livestock manure on land to 76% in 2020 in China as a whole . This could be attributed to the fact that more manure was recycled on land to avoid its direct discharge into rivers, which is the potential effect of the introduced agricultural policies in 2020 compared to 2010. Our results showed that fluoroquinolones accounted for 55% and 56% of rivers' antibiotics in 2010 and 2020, respectively . In 2010, pig and cattle manure were the dominant contributors to antibiotic pollution in rivers. In 2020, antibiotic inputs to rivers were mainly pig and chicken manure. Fig. 2 Annual flows of antibiotics from livestock manure to rivers ( a , b ) and groundwater ( c , d ) in China in 2010 ( a , c ) and 2020 ( b , d ) (tonnes of antibiotics per year). Sources: the MARINA-Antibiotics (China-1.0) model (see Section 2.1 for the model description). Fig. 2 Section title: Antibiotic river pollution Educational score: 4.168272495269775 Domain: biomedical Document type: Study Language: en River pollution varied largely among the 395 Chinese sub-basins . We distinguished between five pollution levels (see Section 2.3 for the definition). In 2010, river sub-basins in Levels I–II received less than 2 g of antibiotics per km 2 of sub-basin area annually . This resulted in approximately 3 tonnes of all selected antibiotics entering rivers in these sub-basins. The contribution of runoff in this river pollution was 45%, and the contribution of soil erosion was 55% (diffuse sources). Most of the Level I–II sub-basins were in the western region of China, covered 38% of the total surface area, and accommodated 2% of the total human population in China in 2010 . Between 2010 and 2020, the total antibiotic input to all rivers in these sub-basins increased by 18%. However, changes in antibiotic pollution during 2010–2020 ranged from −49% (decrease) to +270% (increase) among sub-basins of Levels I–II . This implies that rivers in some western sub-basins became cleaner (decreased pollution), whereas rivers in other sub-basins in the north and northwest became more polluted (increased pollution) during 2010–2020. The livestock numbers of northern sub-basins in Levels I–II increased by 3%–226% between 2010 and 2020 among sub-basins . Moreover, the application of antibiotics to livestock manure on agricultural land increased by 33% between 2010 and 2020 (Supplementary Materials Table S9 ). The combined effects of the changed spatial distribution of livestock production and the application of manure resulted in the northern rivers in Level I–II sub-basins receiving more antibiotics by 2020 . Fluoroquinolone and Sulfonamide groups were more responsible for river antibiotic pollution in these sub-basins in 2020 than in 2010 . They mainly originated from cattle and sheep manure . Fig. 3 River pollution by antibiotics in 395 Chinese sub-basins according to pollution levels and by livestock species in 2010 and 2020. The bar graphs show antibiotic inputs from livestock manure (tonnes year −1 ) to rivers. The pie charts show the share of antibiotic groups in the total antibiotic inputs to rivers from livestock manure (0–1). Levels I–V refer to the pollution levels of total river antibiotic inputs (see Section 2.3 for the definition). Fig. S19 in the Supplementary Materials shows the changes in antibiotic inputs into rivers (%) between 2010 and 2020. Sources: the MARINA-Antibiotics (China-1.0) model (see Section 2.1 for the model description). Fig. 3 Fig. 4 Antibiotics leaching into groundwater in 395 Chinese sub-basins according to pollution level and by livestock species in 2010 and 2020. The bar graphs show antibiotic leaching from livestock manure (kg year −1 ) into groundwater. The pie charts show the share of antibiotic groups in the total leaching into groundwater from livestock manure (0–1). Levels I–V refer to the pollution levels of the total antibiotic leaching into groundwater (definition see Section 2.3 ). Fig. S20 in the Supplementary Materials shows the changes in antibiotic leaching into groundwater (%) between 2010 and 2020. Sources: the MARINA-Antibiotics (China-1.0) model (see Section 2.1 for the model description). Fig. 4 Section title: Antibiotic river pollution Educational score: 4.007468223571777 Domain: biomedical Document type: Study Language: en Rivers in Level III sub-basins received 31 tonnes of antibiotics in 2010, mainly from diffuse sources in which the share of soil erosion was considerable . Most of the Level III sub-basins were in northeastern and southwestern China. These sub-basins covered 22 % of the total surface area. They accommodated 13 % of the total population in China in 2010 . Between 2010 and 2020, the total antibiotic inputs to all rivers in these sub-basins decreased by 11%. As a result, 27 tonnes of antibiotics from livestock production entered rivers in the Level III sub-basins in 2020. Most northeastern Level III sub-basins experienced increased antibiotic pollution in rivers . Most southern sub-basins of Level III were estimated to have decreased by more than 25% in total antibiotic river pollution by the year 2020 . These changes could be attributed to the greater increases in livestock numbers and manure recycling in the northern sub-basins than in the southern sub-basins in Level III by 2020 . In addition, the Level III sub-basins generally had moderate surface runoff and soil erosion, which could facilitate the antibiotics transport through the topsoil layer into rivers . Fluoroquinolones were the predominant antibiotic group, accounting for 58% of the total antibiotic input to river sub-basins in Level III for the years 2010 and 2020 . Cattle manure was the main source of Fluoroquinolones and Tetracyclines in rivers of these sub-basins in both 2010 and 2020 . Section title: Antibiotic river pollution Educational score: 4.176051139831543 Domain: biomedical Document type: Study Language: en Over 90% of antibiotics in the rivers originated from 40% of the basin area in China . These sub-basins were identified as pollution hotspots (Levels IV and V) in this study . Most of this amount was from point sources that accounted for over 94% of total antibiotics in rivers of these sub-basins in 2010 and 2020. In 2010 and 2020, rivers in hotspot sub-basins received 8321 and 3393 tonnes of total antibiotic inputs, respectively. These sub-basins were in central and southern China , which accommodated approximately 84% of the total population in 2020 . Between 2010 and 2020, the antibiotic inputs to rivers of hotspot sub-basins decreased by 59%. However, the changes in antibiotic inputs into rivers ranged from −75% (decrease) to +62% (increase) among Levels IV–V sub-basins during this period. For hotspot sub-basins located in central and southeastern China, our model estimated a decrease of over 50% in river pollution during 2010–2020 . Rivers in some southwestern hotspot sub-basins also became cleaner, with a decrease of more than 25% in total antibiotic inputs by 2020 compared to 2010 . Total antibiotic inputs to rivers in a few hotspot sub-basins in southwestern China increased by 0–25% between 2010 and 2020 . This may also be relevant to the implication of agricultural policies for forbidden direct discharges of livestock manure to rivers and the changed spatial distribution of livestock production during 2010 and 2020. Higher pollution levels in hotspot sub-basins may also largely be associated with higher surface runoff and soil erosion compared to those in the other sub-basins . The proportion of antibiotic groups in rivers varied considerably among sub-basins . Fluoroquinolones contributed more than 40% of the total antibiotic inputs to rivers in hotspot sub-basins between 2010 and 2020 . Pig and cattle manure were the dominant contributors to river pollution with antibiotics from livestock manure in 2010 . Compared to 2010, the contribution of chicken manure to total river pollution in hotspot sub-basins increased by 46% in 2020 . Hotspot sub-basins received approximately 2400 tonnes of antibiotic inputs to rivers from pig and chicken production in 2020. Section title: Antibiotic groundwater pollution Educational score: 4.147174835205078 Domain: biomedical Document type: Study Language: en Our model estimated that 10 and 12 tonnes of antibiotics were leached into groundwater nationally in 2010 and 2020, respectively . This implies that the total leaching of antibiotics into groundwater increased by 15% during 2010–2020 for China as a whole. This could be a result of more recycled manure on land and changed spatial distribution of livestock species in 2020 compared to that in 2010 . For example, in 2010, 1587 tonnes of antibiotics in manure were applied on land in northern sub-basins of China. This amount increased to 2183 tonnes in 2020 (Supplementary Materials Table S9 ). Increased manure recycling was facilitated by existing agricultural policies to avoid direct manure discharges from 2010 to 2020 . Our results showed that Sulfonamides contributed to over 90% of the total antibiotic leaching into groundwater during 2010–2020 . One of the important reasons for this was the good solubility of Sulfonamides. This indicated that Sulfonamides were more easily transported with soil solutions than other groups. Pig manure was the main contributor to the total antibiotic leaching into the groundwater in 2010 . In 2020, the total antibiotic leaching into groundwater was mainly from pig and sheep manure . However, there was large spatial variability among sub-basins . Section title: Antibiotic groundwater pollution Educational score: 3.9864137172698975 Domain: biomedical Document type: Study Language: en In Level I and II sub-basins, less than 0.2 g of antibiotics per km 2 per year were leached into groundwater from livestock production in 2010 . This resulted in approximately 1 tonne of antibiotics entering groundwater. Most of these sub-basins were located in southwestern China , accommodated approximately 9% of the Chinese population, and covered 39% of the total sub-basin area in China in 2010. The share of the sub-basins in total groundwater pollution in China reached 32% in 2020 . This implies that fewer sub-basins were identified as belonging to pollution Levels I–II in 2020 than in 2010. Between 2010 and 2020, changes in antibiotic leaching into groundwater from 2010 to 2020 ranged from −57% (decrease) to +147% (increase) among Level I–II sub-basins . Some sub-basins in the southwest and northeast became cleaner in 2020 than in 2010 . However, the northwest Level I and II Chinese sub-basins became more polluted in 2020 than in 2010 . This was largely associated with the effects of climate change (lower surface runoff) and the relocation of livestock production activities in Level I and II sub-basins during 2010–2020. Sulfonamides constituted the predominant antibiotic group in the total antibiotic groundwater pollution in those sub-basins for both 2010 and 2020 . Compared to 2010, the contributions of sheep manure to antibiotic groundwater pollution became more dominant in 2020 . Fig. 5 Shares of livestock species in river ( a ) and groundwater ( b ) pollution with antibiotics in hotspot sub-basins (Levels IV and V, %). Levels IV and V sub-basins are considered pollution hotspots (definition see Section 2.3 ). The shares of livestock species in the river and groundwater pollution in Levels I–III are in Supplementary Materials Fig. S8 . Sources: the MARINA-Antibiotics (China-1.0) model (see Section 2.1 for the model description). Fig. 5 Section title: Antibiotic groundwater pollution Educational score: 4.020112991333008 Domain: biomedical Document type: Study Language: en Groundwater in Level III sub-basins received 4 tonnes of antibiotics in 2010 . These sub-basins covered 52% of the national area, accommodated 58% of the total population in China , and were mainly located in northeastern and southern China in 2010 . By 2020, the total antibiotic leaching into groundwater increased by 28% in Level III sub-basins compared to that in 2010. As a result, more than 5 tonnes of antibiotics from livestock production leached into groundwater in Level III sub-basins in 2020. Approximately 64% of the total population lived in the Level III sub-basins in 2020. The decreases in antibiotic leaching into groundwater from 2010 to 2020 ranged from 28% to 48% among some southwestern and northeastern sub-basins . These decreases were largely associated with climate change (more surface runoff) and the relocation of livestock species in 2020. Most central and southern sub-basins experienced increased antibiotic leaching into groundwater, ranging from 25% to 161% by the year 2020. Sulfonamides were the dominant antibiotic group in the groundwater of the Level III sub-basins . Compared to 2010, pigs and sheep remained the main contributors to antibiotic groundwater pollution in 2020 . The contributions of chicken and goat manure to groundwater pollution increased by 94% and 25% by 2020, respectively . These increases in antibiotic leaching into groundwater could be attributed to the combined effects of livestock production migration (increased livestock density of chicken and goat) and increased recycling of livestock manure as organic fertilizer between 2010 and 2020 . Fig. 6 The conceptual framework for the ‘building trust’ approach for the large-scale water quality model. This framework is modified based on Strokal et al. . Details on using the ‘building trust’ approach to evaluate the MARINA-Antibiotics (China-1.0) can be found in Section 3.3 . Fig. 6 Fig. 7 Overview of lessons from the MARINA-Antibiotics (China-1.0) model for manure management. Details can be found in Section 3.4 . Fig. 7 Section title: Antibiotic groundwater pollution Educational score: 4.071479797363281 Domain: biomedical Document type: Study Language: en Approximately 10% of the Chinese sub-basin areas were identified as pollution hotspots for groundwater pollution (Levels IV and V) for the years 2010 and 2020 . The hotspot sub-basins received 5 tonnes of total antibiotic leaching to groundwater in 2010. These sub-basins were in central and northern China. They accommodated around 31% of the total Chinese population in 2010 . The total antibiotic leaching into groundwater in hotspots nationally increased by 12% between 2010 and 2020 . This resulted in 6 tonnes of antibiotic leaching into groundwater in hotspot sub-basins in 2020. By 2020, changes in antibiotic leaching into groundwater were estimated to vary from −69% (decrease) to +70% (increase) for hotspot sub-basins . In 2010, pigs were the dominant contributor to antibiotic contamination of groundwater in the hotspots . Between 2010 and 2020, the contributions of chicken and sheep manure to the total antibiotic leaching into groundwater increased by 40% and 67%, respectively . Sulfonamides remained the main antibiotic group in groundwater pollution in 2020. In 2020, β-lactams from chickens, pigs, and ducks accounted for more than 10% of the total antibiotics leaching into groundwater . Section title: Model evaluation, limitations, and uncertainties Educational score: 3.3009750843048096 Domain: biomedical Document type: Study Language: en We applied four model evaluation options following a widely used approach to build trust in the models (see Section 2.2 ). For Option 1, we compared the following model inputs with other datasets: soil pH, soil temperature, soil organic carbon content, and soil saturation. The selected model inputs were plotted on a 1:1 line. We assessed the model performance using two statistical indicators: Pearson’s coefficient of determination ( R P 2 , from 0 to 1) and the Nash-Sutcliffe efficiency (NSE, from −∞ to 1). According to the performance rates from Moriasi et al. , the differences between our model inputs and independent datasets were acceptable: R P 2 > 0.8 and NSE >0.6 . Section title: Model evaluation, limitations, and uncertainties Educational score: 4.112703323364258 Domain: biomedical Document type: Study Language: en Option 2 showed that our model outputs for Tetracyclines, Fluoroquinolones, and Sulfonamides as the dominant contributors to antibiotic pollution in rivers in China were in line with those of existing studies . We modeled that pig manure contributed approximately 1106 and 517 tonnes of antibiotic inputs to the Yangtze River basins in 2010 and 2020, respectively. Chen et al. used the level Ⅳ fugacity model to evaluate the emission, multimedia fate, and risk of antibiotics in the entire Yangtze River basin. Their model results indicated that, between 2013 and 2021, approximately 514–903 tonnes of antibiotics were introduced into the Yangtze River from pig production. Our model results were slightly higher than those of their study because we were more complete regarding the number of antibiotics used (24 in our study and 18 in Chen et al. ). Zhang et al. also indicated that pigs accounted for over 40% of river antibiotic inputs in 2013. This was demonstrated by our main livestock species responsible for antibiotic river pollution in 2010. Section title: Model evaluation, limitations, and uncertainties Educational score: 3.6763010025024414 Domain: biomedical Document type: Study Language: en Option 3 focused on comparing the spatial variability of pollution hotspots with those of other studies . For instance, the river pollution hotspots in central and northern China in 2010 and 2020 were in line with the findings of previous studies . Generally, these sub-basins (e.g., Hai and Yangtze River sub-basins) had high livestock densities and high manure inputs per km 2 both in 2010 and 2020. This was in line with previous studies (e.g., Refs. ). Other studies have shown that areas with higher direct manure discharges received more pollutants from rivers in 2010 . This was also demonstrated by our hotspot sub-basins in 2010. Examples were sub-basins in southern China (e.g., Yangtze River sub-basins) with higher direct discharges of livestock manure to rivers than those in northern China (e.g., Songhua River sub-basins) in 2010. Other studies have indicated that antibiotics in rivers were generally higher in central and eastern China than in western China . Huang et al. indicated that antibiotic groundwater pollution was higher in the Hai River Basin than in the Yangtze and Pearl River Basins, which was consistent with our study for both 2010 and 2020. Section title: Model evaluation, limitations, and uncertainties Educational score: 4.013497829437256 Domain: biomedical Document type: Study Language: en For Option 4, we reflected on our modeling approach. Our model was an integrated modeling approach that combined the existing knowledge and literature on the soil processes of antibiotics that can be transported to rivers and groundwater. First, we reviewed the literature on the physical, biological, and chemical processes that can affect the degradation and adsorption of antibiotics in the soil and soil erosion . We developed an approach for the degradation and adsorption of antibiotics in soil particles and solutions based on expert knowledge of field experiments. We also used expert knowledge of soil erosion supported by literature to estimate the antibiotics in soil particles transported from agricultural land to rivers. The four aforementioned options helped us to better understand the performance of our model (inputs, outputs, and approach) and to better interpret the results. Section title: Model evaluation, limitations, and uncertainties Educational score: 4.138071060180664 Domain: biomedical Document type: Study Language: en However, our model did not account for sources such as antibiotics in sewage systems or antibiotic manufacturing and processing. Thus, the river and groundwater pollution levels may have been underestimated. Extreme events (e.g., heavy rainfall) were not considered, which may have resulted in more antibiotics entering rivers through runoff and soil erosion and leaching into groundwater at certain moments. We focused on 2010 and 2020. Thus, the trends in our pollution levels during 2010 and 2020 may not consistently decrease but could initially increase and then decrease. Our model results were under- or overestimated in sub-basins, depending on their agricultural development. Future studies may need to quantify the processes and dynamics of antibiotic inputs to rivers and groundwater in more detail and consider the by-products that emerge during degradation processes for more years. However, this study focused on livestock and manure production. We quantified the flows of 24 antibiotics from livestock into rivers and groundwater. We considered important sources of antibiotics in livestock production: pigs, cattle, chickens, ducks, goats, sheep, and buffaloes. Our selection of seven livestock species was justified by three main reasons. First, these livestock species are of high economic importance for the whole of China . The selected livestock species contributed largely to China’s agricultural production and food systems . These livestock species could reflect those most widely produced across the whole of China, thus covering diverse production systems . Second, livestock species with potentially varying environmental impacts were included to explore how different manure management systems (e.g., storage vs. grazing) affected inputs of pollutants into rivers and leaching into groundwater between 2010 and 2020 . Third, we recognized that the main livestock species may vary geographically, as in northern vs. southern China, where environmental and agricultural factors influenced species prevalence . However, the selections of these seven livestock species reflected the broader national significance rather than focusing on region-specific species. They were important across multiple regions, even though their relative importance varied by location. Thus, the uncertainties associated with missing sources did not affect our conclusions. Future studies could use our modeling tool and add missing sources to better understand the contribution of other sources to antibiotic pollution. Section title: Model evaluation, limitations, and uncertainties Educational score: 4.145411014556885 Domain: biomedical Document type: Study Language: en In this study, we developed a steady-state, large-scale water quality model to estimate antibiotic loadings input into rivers and leaching into groundwater at the sub-basin scale. We estimated loadings of antibiotics into waters (not concentrations). Our mode did not consider local-scale factors, such as the exact distance between farms and nearby rivers. The current model inputs were all at the sub-basin scale. Thus, our model may not be directly used for local analyses (e.g., specific farms or watersheds). However, our modeling approach was integrated and more process-oriented than the existing models . Our model was run annually to examine changes in river and groundwater pollution from antibiotics in livestock production in 2010 and 2020 at the sub-basin scale. Our model can also be used for other years if data are available. We considered the different pathways that contribute to antibiotics in rivers and groundwater, including surface runoff, soil erosion, and leaching. Seven dominant livestock species in China were considered. Our approach can simultaneously quantify antibiotic river and groundwater pollution from 24 antibiotics and seven livestock species, which has not been done previously for over 300 sub-basins in China. Because our model was integrated, process-based, and uncalibrated, it offers an opportunity to conduct future analyses and account for climate changes, technological developments, and food production drivers. All datasets used in our study were widely used and accepted by the scientific community, and they were freely available for download [ 1 , , , , , , 25 , 44 , 57 , 69 ]. Section title: Lessons from water quality modeling for manure management Educational score: 4.029610633850098 Domain: biomedical Document type: Study Language: en Our analyses drew four lessons regarding antibiotic pollution in rivers and groundwater. First, our study helped identify the contributions of livestock species to river and groundwater pollution in 2010 and 2020. This study was conducted in China. We showed that pig and cattle manure were the dominant contributors to river pollution with antibiotics in 2010 . In 2020, pig and chicken production became the dominant sources of antibiotic-related river pollution. Other countries can use our new modeling tool and increase their understanding of the species and efforts required to reduce livestock-production-related river and groundwater pollution. From our analyses, we learned that, for non-hotspot sub-basins (Levels I–III), a reduction of water pollution with antibiotics was needed from pig, sheep, and cattle production. For hotspot sub-basins (Levels IV–V), future water pollution strategies should focus more on managing chicken and pig manure. This information supported the formulation of livestock-specific manure management. Our model can be a useful tool for projecting future antibiotic rivers and groundwater and supporting decision-makers for specific livestock species that would be prioritized in manure management policies in the future. Section title: Lessons from water quality modeling for manure management Educational score: 4.098555564880371 Domain: biomedical Document type: Study Language: en Second, our study provided a better understanding of the antibiotic groups from livestock production toward rivers and groundwater. We showed that Sulfonamides were important for river pollution in Level I sub-basins, and this pollution resulted mainly from the manure of sheep and cattle, both in 2010 and 2020. Fluoroquinolones and Sulfonamides were the most important river pollutants in Levels II–V sub-basins and mainly originated from chicken and pig manure in 2020. This study focused on seven livestock species due to their economic significance (e.g., most widely farmed and consumed livestock in China ) and data availability. Future research can consider expanding to include more livestock species based on our model. We also realized that, in reality, there may be even more antibiotics present in Chinese waters, but this model can be easily extended to other antibiotics. In other countries, other antibiotics may dominate in the use for livestock; for example, Tetracyclines were predominantly used in livestock production in the United States , Cyprus, Bulgaria, and Portugal , whereas in Australia, Macrolides were the main antibiotic groups used in livestock production . Applying our modeling tool could help those countries understand which livestock species can contribute to water pollution. Section title: Lessons from water quality modeling for manure management Educational score: 3.4927148818969727 Domain: biomedical Document type: Study Language: en Third, our results supported existing agricultural policies for better groundwater and river pollution control with other pollutants in China. Our results indicated less antibiotic river pollution and more groundwater pollution during 2010–2020 in China as a whole . Manure contains other pollutants, such as nutrients and pathogens . With the implications of agricultural policies, for example, ‘Livestock and Poultry Manure Utilization Action Plan ’ , ‘14th Five-Year National Agricultural Green Development Plan’ , and China’s livestock relocation policies , etc.), more manure recycling on agricultural land may not only affect water pollution with antibiotics in China as we estimated in our study. These may also reduce nutrient or pathogen pollution in rivers. This has also been demonstrated by existing studies on other pollutants (e.g., nutrients). Recycling manure was shown to be the most cost-effective option for reducing future coastal eutrophication . However, there may be a trade-off between policies facilitating more manure recycling and groundwater pollution, as indicated by our study's changes in antibiotic groundwater pollution . This implies that future agricultural policies are required to avoid the trade-off between the recycling of manure on land and groundwater pollution. Section title: Lessons from water quality modeling for manure management Educational score: 3.951709508895874 Domain: biomedical Document type: Study Language: en Fourth, our results provided policymakers with a better understanding of the development and implementation of clean water strategies for manure management in a spatially explicit manner. Sub-basin analyses can help identify pollutants' origin and sources to formulate effective solutions for agriculture-related pollution. Our model results showed that antibiotic river pollution in some sub-basins increased, whereas in others (e.g., southern sub-basins in China) decreased from 2010 to 2020. This may be associated with increased livestock production in China’s northern and southern sub-basins between 2010 and 2020. This implied that future manure management policies for these sub-basins need to be combined with better treatment to avoid more pollutants in rivers. We also found that avoiding the direct discharges of manure could considerably decrease antibiotic inputs to rivers in the southern sub-basins of China. However, our results indicated that antibiotic leaching into groundwater increased by 11% from 2010 to 2020 in these southern sub-basins. This implied the importance of considering the potential trade-off between manure recycling and groundwater for developing future water pollution controls. As we indicated in the Introduction section, our study could raise the attention of policymakers, the public, and other stakeholders on the importance of considering antibiotics in national water quality policies and monitoring programs in the future. Section title: Conclusions Educational score: 4.178031921386719 Domain: biomedical Document type: Study Language: en This study was the first attempt to account for antibiotics from livestock production in rivers and groundwater in China at the sub-basin scale. The MARINA-Antibiotics (China-1.0) model was developed and evaluated to quantify the flow of 24 antibiotics into rivers and leaching into groundwater from seven livestock species in 395 Chinese sub-basins and to examine changes in antibiotic water pollution between 2010 and 2020. In 2010 and 2020, 8364 and 3436 tonnes of antibiotics entered rivers and groundwater, respectively, causing antibiotic pollution. 50–90% of the antibiotic losses to rivers and groundwater originated from 40% of the basin areas in China between 2010 and 2020. The total river antibiotic inputs decreased by 59% during 2010–2020 because of fewer manure point sources. In contrast, total antibiotic leaching into groundwater increased by 15% nationally, which was largely because of increased manure recycling. Fluoroquinolones were responsible for 55% of the antibiotics in Chinese rivers in 2010 and 2020 and mainly originated from pigs, cattle, and chicken manure. Sulfonamides were responsible for over 90% of groundwater antibiotics, mainly from pig and sheep manure. Our study supports future agriculture-related policy designs in China. Section title: CRediT authorship contribution statement Educational score: 0.9720918536186218 Domain: other Document type: Other Language: en Qi Zhang: Writing - Original Draft, Visualization, Validation, Methodology, Formal Analysis, Data Curation, Conceptualization. Yanan Li: Writing - Review & Editing, Methodology, Conceptualization. Carolien Kroeze: Writing – Review & Editing, Supervision, Conceptualization. Milou G.M. van de Schans: Writing - Review & Editing, Methodology. Jantiene Baartman: Writing - review & Editing, Methodology. Jing Yang: Writing - Review & Editing, Investigation. Shiyang Li: Writing - Review & Editing, Investigation. Wen Xu: Writing - Review & Editing, Supervision. Mengru Wang: Writing - Review & Editing. Lin Ma: Writing - Review & Editing, Supervision. Fusuo Zhang: Writing - Review & Editing, Supervision. Maryna Strokal: Writing - Review & Editing, Supervision, Methodology, Conceptualization. Section title: Data availability Educational score: 1.4460724592208862 Domain: biomedical Document type: Other Language: en All sources to model inputs are provided in the Supplementary Materials. The model is processed in the R script. Model outputs are presented in the manuscript and the Supplementary Materials. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Study | biomedical | en | 0.999996 |
PMC11697714 | Section title: Introduction Educational score: 4.576533794403076 Domain: biomedical Document type: Study Language: en The Orobanchaceae family encompasses a diverse array of mostly parasitic plant species, which, after major rearrangements in the Lamiales, includes the genus Castilleja , commonly known as Indian Paintbrush. 1 , 2 With a distribution spanning the Americas and some species documented in Asia and Russia, Castilleja comprises over two hundred annual and perennial herbaceous species. 3 Host dependence within the Orobanchaceae family exhibits a wide spectrum. Striga species, for example, are obligate hemiparasites that rely on hosts for survival while retaining photosynthetic capabilities. In contrast, Orobanche species exemplify holoparasitism, entirely dependent on hosts for sustenance due to the loss of photosynthetic function. 4 Phtheirospermum japonicum , Triphysaria, and Castilleja , on the other hand, are facultative parasites, capable of transitioning between autotrophic and hemiparasitic lifestyles based on environmental conditions. Root-parasitic plants have developed a specialized organ, the haustorium, to establish connections with the host’s vascular system. 5 , 6 The haustorium allows for the transfer of water and nutrients from the host to the parasitic plant, enabling their exploitation of host resources and successful adaptation to nutrient-deficient environments. Within the life cycle of Orobanchaceae, the detection and utilization of host-derived signaling molecules play a key role in the parasitic lifestyle: Notably, strigolactones, a group of carotenoid-derived plant hormones, are well-known for their role in inducing germination of seeds from obligatory parasitic Orobanchaceae species. 7 , 8 , 9 Many parasitic Orobanchaceae have evolved a large clade of diversified KAI2 proteins (KAI2d) as receptors for exogenous strigolactones. The diversification of these proteins is regarded as the main driver of parasitism for these plants. 10 While the host specificity of Castilleja species and the structure of the Castilleja haustorium have been extensively described, 11 , 12 , 13 , 14 , 15 , 16 it is unclear if these plants can perceive strigolactones and whether strigolactones have any biological role in the parasitic lifestyle of Castilleja . As a matter of fact, it has been demonstrated that Castilleja seeds are not impacted by the hemiparasitic nature of Castilleja , but that germination occurs after a several weeks or months long moist chilling period. 17 Section title: Introduction Educational score: 3.5876054763793945 Domain: biomedical Document type: Study Language: en Here we show that strigolactones are perceived by multiple proteins of the diverged clade of KAI2 proteins and trigger the formation of haustorium-like structures in Castilleja . Section title: Strigolactones trigger the formation of haustorium-like root structures in Castilleja Educational score: 4.203861236572266 Domain: biomedical Document type: Study Language: en We investigated the potential biological role of strigolactones in the life cycle of Castilleja species. To this end, we germinated stratified seeds from Castilleja wightii , Castilleja affinis , and Castilleja foliolosa under two different conditions: in the presence of H 2 O and in the presence of the chemical strigolactone analog GR24 5DO. Despite the different conditions, germination efficiency did not vary significantly between the two environments . However, we noted marked morphological differences in the emergent seedlings. Seedlings that germinated in H 2 O developed a robust primary root system accompanied by an array of lateral root hairs . In contrast, the seedlings exposed to GR24 5DO presented a slenderer root structure devoid of lateral root hairs . This divergence in morphology was consistent across the three tested Castilleja species. We quantified the percentage of germinated seedlings that developed such root structure after exposure to different strigolactones but found no significant difference . When we examined the terminal root structure more closely, we noticed that GR24 5DO grown plants had a smaller root cap and smaller cells at the tip of the structure compared to water grown plants . We used Rhodamine 123, which serves as an indicator for mitochondrial transmembrane potential, to confirm the viability of these cells . In summary, the structures grown in the presence of GR24 5DO more closely resemble the elongated state characteristic of root-parasitic plants such as Striga than they do typical roots. Figure 1 GR24 triggers the formation of haustorium-like structures in Castilleja (A) Germination assay showing percentages of germinated C. wightii and C. affinis seeds when germinated on H 2 O vs. GR24 5DO. Error bars represent the standard deviation of three independent measurements. (C and E) Heterotrophic root phenotypes and (B, D, and F) possibly parasitic phenotypes of C. wightii and C. affinis after germination on GR24 5DO. Section title: Strigolactones trigger the formation of haustorium-like root structures in Castilleja Educational score: 3.92172908782959 Domain: biomedical Document type: Study Language: en These observations suggest that while strigolactones may not function as a germination signal for Castilleja species, they do effectively mimic a host plant, participating in triggering a parasitic state in the seedlings immediately post-germination when present. Therefore, strigolactones appear to play a crucial role in activating post-germination modifications in Castilleja , preparing for a parasitic lifestyle. Considering the impact of strigolactones on the morphological development of Castilleja , we set out to identify the strigolactone receptors within Castilleja foliolosa and aimed to characterize these proteins. Section title: Genome sequence of Castilleja foliolosa reveals 15 kai2d genes Educational score: 4.165777206420898 Domain: biomedical Document type: Study Language: en To investigate the potential presence of strigolactone receptors in Castilleja , we sequenced the genome of Castilleja foliolosa , also known as Woolly Indian Paintbrush. The assembly spanned 551 contigs, adding up to a total length of approximately 752 Mbp with an N50 of 11,150,047 bp and an N90 of 2,884,952 bp ( Table S1 ). The haploid genome length, as determined through a K-mer distribution analysis, 18 measured approximately 555 Mbp, and a Smudgeplot analysis 18 indicated that the genome is likely diploid , which is in agreement with a previous study. 19 BUSCO analysis against the eudicots_odb10 lineage dataset 20 showed that 87.5% of the BUSCOs were complete ( Table S2 ). Section title: Genome sequence of Castilleja foliolosa reveals 15 kai2d genes Educational score: 4.256780624389648 Domain: biomedical Document type: Study Language: en We compared the genome of Castilleja foliolosa to the published genomes of other species within the Orobanchaceae family, namely Phtheirospermum japonicum , 21 Striga asiatica , 22 and Orobanche cumana . 23 As anticipated, a substantial number of syntenies were found between Castilleja foliolosa and these other parasitic plant genomes, with the highest count of 21,204 syntenies noted with Phtheirospermum japonicum , followed by 15,251 syntenies with Orobanche cumana and 12,476 syntenies with Striga asiatica . Figure 2 Strigolactone receptors in the genome of Castilleja foliolosa (A) Circos plot showing synteny between C. foliolosa and 3 other parasitic plants: The facultative hemiparasite P. japonicum , the obligate hemiparasite S. asiatica , and the holoparasite O. cumana . The scale has been adjusted for genome size and is in Mbp. The number of syntenies to C. foliolosa are 21,204 with P. japonicum , 15,251 with O. cumana , and 12,476 with S. asiatica . (B) Phylogenetic tree of D14, KAI2c, and KAI2d proteins from C. foliolosa , P. japonicum , S. asiatica , and O. cumana . Proteins in black boxes were used for differential scanning fluorimetry (DSF) as shown as follows: (C–F) DSF of C. foliolosa KAI2d8, KAI2d14, KAI2d15, and KAI2i1, showing their destabilization upon presence of the chemical strigolactone analog GR24 5DO. DSF curves are shown as mean values of three independent measurements. Section title: Genome sequence of Castilleja foliolosa reveals 15 kai2d genes Educational score: 4.1178154945373535 Domain: biomedical Document type: Study Language: en Utilizing a BLAST search, potential strigolactone receptors were identified. We discovered 1 gene encoding for DWARF14, 4 genes encoding KAI2c paralogs, 2 genes encoding KAI2i proteins, and 15 genes encoding KAI2d proteins . This high number of paralogs in the KAI2d protein clade is in line with other parasitic plants in the Orobanchaceae, suggesting a potential function as strigolactone receptors in Castilleja as well. We collected bulk RNA from Castilleja affinis and Castilleja foliolosa seedlings and conducted PacBio Iso-Seq to identify full-length transcripts. Additionally, we analyzed a publicly available RNA-seq dataset from Castilleja miniata . In all three species, we were able to detect the presence of transcripts from several kai2d orthologs, including those that we analyzed from Castilleja foliolosa . Section title: KAI2d proteins from Castilleja foliolosa are putative strigolactone receptors Educational score: 4.110756874084473 Domain: biomedical Document type: Study Language: en To further investigate if these predicted KAI2 proteins serve as strigolactone receptors, we heterologously produced five of them, namely KAI2d8, KAI2d9, KAI2d14, KAI2d15, and KAI2i1, in Escherichia coli . We were, unfortunately, unable to produce sufficient amounts of the other orthologs from E. coli . By conducting differential scanning fluorimetry (DSF), we observed a clear, concentration-dependent destabilization of KAI2d14, KAI2d15, and KAI2i1 in the presence of the chemical strigolactone analog GR24 5DO. A weaker but discernible destabilization was noted with KAI2d8, strongly suggesting that these KAI2 proteins are indeed strigolactone receptors . We were, unfortunately, unable to obtain sufficient amounts of KAI2d9 for the DSF assay. Section title: KAI2d15 features a methionine cluster at the substrate pocket entrance Educational score: 4.297945976257324 Domain: biomedical Document type: Study Language: en To obtain additional insight into the strigolactone perception in Castilleja , we solved the crystal structure of KAI2d15 at a resolution of 1.8 Å ( Table S3 ). As expected, the protein adopted a canonical α/β hydrolase architecture, with a 4-helix lid domain covering the substrate binding pocket containing a Ser/His/Asp catalytic triad at its base. The substrate binding pocket was quite voluminous, measuring 908 Å 3 , which surpassed the 861 Å 3 found in the strigolactone receptor KAI2d4 from Orobanche minor , 24 but was smaller than the 1111 Å 3 detected in the highly sensitive SL receptor HTL7 from Striga hermonthica . 25 Figure 3 Structural and biochemical analysis of C. foliolosa KAI2d15 (A) Crystal structure of C. foliolosa KAI2d15, showing the substrate binding pocket in red, and highlighting the residues of the catalytic triad (S95, D217, H246), and the methionines surrounding the entrance to the pocket (M142, M153, M157). (B) Rotated and zoomed in view of the methionines surrounding the pocket entrance. Note that an alternative side-chain conformation of M142 is shown. (C) Chemical structures of the strigolactone molecules used in the following DSF assay. (D and E) DSF assay comparing the destabilization of C. foliolosa KAI2d15 wild type and a M142V M153V M157V variant upon the presence of different strigolactone molecules. Concentrations closest to the equilibrium are highlighted in bold for easier comparison. DSF curves are shown as mean values of three independent measurements. Section title: KAI2d15 features a methionine cluster at the substrate pocket entrance Educational score: 4.131045341491699 Domain: biomedical Document type: Study Language: en We identified three methionine residues at the entrance to the binding pocket . To study the effect of these methionine residues on the receptor’s substrate specificity and sensitivity, we created a protein variant, replacing the three methionines with valines (KAI2d15 M142V M153V M157V). We carried out separate DSF experiments with four different strigolactone molecules, testing both the variant and the wild-type protein. The mutant protein showed destabilization at lower ligand concentrations when GR24 or 5-deoxystrigol were present, while the wild-type protein destabilized at lower concentrations of strigol or orobanchol . Section title: Tested Castilleja foliolosa KAI2 proteins are high-turnover enzymes Educational score: 4.374853134155273 Domain: biomedical Document type: Study Language: en We examined the enzymatic properties of Castilleja foliolosa of KAI2d8, KAI2d9, KAI2d14, KAI2d15, and KAI2i1 in Michaelis-Menten experiments using the large fluorescent strigolactone analog Yoshimulactone Green (YLG). All investigated proteins turned out to be efficient high-turnover enzymes, with turnover numbers ranging between 600 s −1 and 2780 s −1 and catalytic efficiencies between 4.2·10 8 s −1 M −1 and 2.6·10 9 s −1 M −1 . We specifically compared Michaelis-Menten parameters between the KAI2d15 wild type and the mutant, in which three of the methionines at the substrate pocket entrance had been replaced with valines (KAI2d15 M142V M153V M157V). While the turnover numbers (k cat ) of these proteins showed no significant difference, we found a 3-fold decrease in the Michaelis constant (K M ) for wild-type KAI2d15 as compared to the mutant version (0.8 μM in wild-type KAI2 vs. 2.4 μM in KAI2d15 M142V M153V M157V) . We further noticed a proportional relationship between the Michaelis constants and the turnover rates of these proteins , suggesting a trade-off between substrate turnover and affinity in the catalytic reaction. KAI2d15 wild type was a notable exception, maintaining both high k cat and low K M . Strikingly, the KAI2d15 M142V M153V M157V version of the protein lay well within the trendline shared with the other KAI2d proteins, as a result of the higher K M value compared to wild type. These results suggest that the properties of the methionine residues located at the entrance to the substrate binding pocket allow KAI2d15 to overcome this trade-off between substrate turnover and affinity that appears to be characteristic of the other investigated KAI2d proteins from Castilleja foliolosa . Figure 4 Michaelis-Menten assays of C. foliolosa KAI2d proteins with the fluorescent strigolactone analog Yoshimulactone Green (YLG) as substrate (A–E) Comparison of Michaelis-Menten values between different C. foliolosa KAI2 proteins (The chemical structure of YLG is shown in A). (F) Correlation between turnover rates and Michaelis constants of different C. foliolosa KAI2 proteins. Error bars represent the standard deviation of three independent measurements. Section title: Discussion Educational score: 4.323828220367432 Domain: biomedical Document type: Study Language: en Strigolactones have long been recognized as germination signals for root-parasitic plants from the Orobanchaceae family. Beyond this, they can also function as chemoattractants for host tropism. 26 While strigolactones serve as potent germination stimulants for obligate parasites such as Striga and Orobanche , their role is different in the facultative parasite Phtheirospermum japonicum , where they stimulate germination only in the absence of nitrate ions. 27 In our study, we discovered a role for strigolactones in Castilleja , another facultative parasite. Here, strigolactones do not cause germination but instead act post-germination. Castilleja can adopt a parasitic lifestyle when their root system encounters a host organism – a behavior well documented in adult plants, which form lateral haustoria upon exposure to a host. 13 However, there is no data supporting that strigolactones are involved in the parasitic transition. We demonstrate that the presence of strigolactones during germination suppresses the development of a typical root system and instead leads to the formation of a structure reminiscent of the elongated stage known from other root-parasitic plants, possibly representative of a parasitic state in Castilleja . This adds a layer of complexity to our understanding of the functions of strigolactones within the Orobanchaceae family. Section title: Discussion Educational score: 4.271737098693848 Domain: biomedical Document type: Study Language: en The results of our syntenic block analysis and sequence comparison provide insights into the genomic relationships among the four species of plants studied, which include Orobanche cumana , Castilleja foliolosa , Striga asiatica , and Phtheirospermum japonicum . All these species belong to the Orobanchaceae family and display parasitic lifestyle traits; however, the degree and nature of parasitism vary among them. Castilleja foliolosa and Phtheirospermum japonicum , both facultative hemiparasites, shared the highest number of syntenic blocks, indicating a closer genomic relationship, contrasting with Orobanche cumana and Striga asiatica , which have different parasitic strategies. When we examined the strigolactone receptor sequences, a family of genes known for their rapid evolution and critical role in plant parasitism, we found that the receptors in Castilleja foliolosa are most closely related to those in Phtheirospermum japonicum . This provides additional evidence of a closer evolutionary relationship between these two species, and it further suggests that their shared facultative parasitic lifestyle has them placed closer to their common ancestor than obligatory parasites in the Orobanchaceae, which are assumed to have evolved later. 4 Section title: Discussion Educational score: 4.575153350830078 Domain: biomedical Document type: Study Language: en We identified 15 paralogs of the diverged clade KAI2 proteins (KAI2d) encoded in the genome of Castilleja foliolosa , one of which, KAI2d15, showed characteristics previously not observed in a strigolactone receptor. We found 3 methionine residues in the crystal structure of KAI2d15 that surround the entrance to the protein’s substrate binding pocket, including an alternative side-chain conformation of M142. We speculate that there might be a role of the branched, flexible methionines in the more favorable accommodation of strigol and orobanchol, which are slightly larger than GR24 and 5-deoxystrigol. The methionines also appear to optimize substrate affinity and turnover. In many enzymes, achieving a high affinity for a substrate often comes at the cost of efficient substrate turnover. This is largely due to the binding dynamics: a tightly bound substrate might be converted efficiently but released slowly, leading to a longer turnover cycle. 28 We observed a linear trade-off between these two catalytic parameters in all investigated KAI2 proteins, except KAI2d15, and remarkably, the trade-off was restored in the KAI2d15 M142V M153V M157V mutant. Flexible methionine residues at the pocket entrance might aid substrate translocation, resulting in a lower K M . However, their flexibility could also play a role in destabilizing the enzyme-product interaction post-catalysis, making product release more efficient and maintaining a higher k cat . Thus, a possible dual role of the methionines in both enhancing substrate binding and promoting product release might be the molecular basis for KAI2d15 mitigating the typical trade-off observed in enzyme kinetics. The pocket entrance methionine residues might also affect the affinity for GR24 specifically. The sulfur atom in methionine is capable of engaging in various types of interactions with aromatic moieties, including van der Waals forces and sulfur-π interactions. However, a comprehensive understanding of these interactions would necessitate studying a broader variety of strigolactones to discern the specificity and affinity nuances. The presence of methionines in the entrance to the SL binding pocket has been previously reported in the case of Striga hermonthica HTL4. 25 While two of the methionines in the pocket entrance in Castilleja foliolosa KAI2d15 align with methionines in ShHTL4, the third methionine (M157) corresponds to a phenylalanine in ShKAI2d4 (F157) . It is also noteworthy that none of the Striga hermonthica or Striga asiatica KAI2d proteins contain methionine at this position. A different methionine in ShKAI2d4 (M154) is located deeper inside the pocket, rather than at its entrance. In Striga hermonthica , the presence or absence of a crucial hydrogen bond between F150/Y151 and L178 determines substrate specificity. 25 This structural basis, however, does not seem to be applicable to the protein we investigated. Castilleja foliolosa KAI2d15 features a histidine instead of a phenylalanine/tyrosine at this position. In addition, this histidine is about 4.7 Å away from the corresponding leucine, likely too distant for hydrogen bonding . Section title: Discussion Educational score: 4.325142860412598 Domain: biomedical Document type: Study Language: en A notable observation is the generally high turnover rates exhibited by Castilleja foliolosa ’s KAI2 proteins. While the turnover rates of SL receptors vary, especially D14 proteins are characterized by slow or even single-turnover rates. 29 , 30 , 31 The proteins in this study demonstrated substantial catalytic efficiencies, the highest achieved by KAI2d15 at 2.6·10 9 s −1 M −1 on YLG, which is in the range of a diffusion-limited enzyme. While it is not immediately clear whether there are advantages to high-turnover SL receptors, it seems intuitive that such a receptor, which rapidly hydrolyzes strigolactones, would depend on constant strigolactone input to maintain its activation and availability for binding to the F box protein MAX2, the next step in the strigolactone signaling pathway after SL perception by its receptor. 8 Diverse strigolactone turnover rates through different receptors could possibly enable the plant to map out strigolactone gradients in its surroundings. Another reason for the elevated catalytic activity observed in certain KAI2d proteins could be a decrease in strigolactone sensitivity. This could be through either the degradation of the host’s ligand before signal transduction begins or by necessitating elevated levels of strigolactone for a prolonged signaling event to take place. Additionally, it might be beneficial for a hemiparasite to either eliminate or disregard its own strigolactone production in the root area. Section title: Discussion Educational score: 4.0898237228393555 Domain: biomedical Document type: Study Language: en In summary, our research reveals that Castilleja possesses a large clade of KAI2d proteins, acting as strigolactone receptors, participating in activating a parasitic state in the plant. Notably, one of these receptors operates as a diffusion limited enzyme that achieves specificity for larger strigolactones and high catalytic efficiency through a cluster of methionine residues at the pocket entrance. Hopefully, in the future, transgenic Castilleja plants will be available to study the function of these receptors in isolation and in planta . We hope that our findings will lay the groundwork for future studies investigating the role of strigolactones in Castilleja . Section title: Limitations of the study Educational score: 4.141078948974609 Domain: biomedical Document type: Study Language: en Our study reveals important insights into strigolactone perception in Castilleja and opens avenues for future research. The development of a reliable transformation system for Castilleja species would allow the validation of our findings through genetic approaches, such as knockout studies of individual kai2d genes. Among the fifteen identified KAI2d paralogs, we successfully characterized five through biochemical analyses, leaving opportunities to explore the properties of additional family members as expression systems are optimized. While we observed clear morphological changes in seedling root structures upon strigolactone treatment, future studies can further illuminate the cellular and molecular nature of these structures and their relationship to parasitic states. These considerations highlight promising directions for future studies that will further expand our understanding of strigolactone signaling in facultatively root-parasitic plants. Section title: Lead contact Educational score: 1.0147104263305664 Domain: other Document type: Other Language: en Further information and requests for resources should be directed to and will be fulfilled by the lead contact, Marco Bürger ( mburger@salk.edu ). Section title: Materials availability Educational score: 1.037171483039856 Domain: biomedical Document type: Other Language: en This study is based on existing materials and did not produce new materials or reagents. Section title: Data and code availability Educational score: 1.2560991048812866 Domain: biomedical Document type: Other Language: en • The genome sequence of Castilleja foliolosa has been deposited in the NCBI GenBank under accession number GenBank: JAVIJP000000000. • The structural coordinates and diffraction data of Castilleja foliolosa KAI2d15 have been deposited in the Protein DataBank under accession code PDB: 8TMX . • Data reported in this article will be shared by the lead contact upon request. • This article does not report the original code. • Any additional information required to reanalyze the data reported in this work article is available from the lead contact upon request. Section title: Acknowledgments Educational score: 0.8861296772956848 Domain: other Document type: Other Language: en We extend our gratitude to Dr. Xuelin Wu (Salk Institute for Biological Studies) for the generous help with microscopy. This work was supported by the NGS Core Facility of the Salk Institute with funding from NIH-NCI CCSG : P30 014195 , the Chapman Foundation and the Helmsley Charitable Trust . We thank the staff at Advanced Light Source at the Berkeley Center for Structural Biology for their assistance with X-ray data collection. The Berkeley Center for Structural Biology was supported in part by the NIH, National Institute of General Medical Sciences and the Howard Hughes Medical Institute . The Advanced Light Source was supported by the Director, Office of Science, Office of Basic Energy Sciences of the U.S. Department of Energy . This study has been supported by the 10.13039/100000002 National Institutes of Health (NIH) grant R35 GM122604 . Joanne Chory is an investigator of the Howard Hughes Medical Institute. Section title: Author contributions Educational score: 0.7654440402984619 Domain: other Document type: Other Language: en M.B. and D.P. conducted the experiments. All authors wrote the article. Section title: Declaration of interests Educational score: 0.8662789463996887 Domain: other Document type: Other Language: en The authors declare no conflicts of interest. Section title: Key resources table Educational score: 3.521372079849243 Domain: biomedical Document type: Other Language: en REAGENT or RESOURCE SOURCE IDENTIFIER Bacterial and virus strains BL21-CodonPlus (DE3)-RIL competent cells Agilent 230245 Chemicals, peptides, and recombinant proteins GR24 5DS Strigolab EN1010 Rhodamin 123 Sigma-Aldrich 6030951 Isopropyl β-D-1-Thiogalactopyranosid, IPTG, Isopropyl β-D-Thiogalactosid (IPTG) Sigma-Aldrich I6758 Tris(2-carboxyethyl)phosphin -hydrochlorid (TCEP) Sigma-Aldrich C4706 HRV 3C Protease Takara 7360 SYPRO Orange ThermoFisher S6651 Critical commercial assays Nanobind plant nuclei kit PacBio 102-207-800 SMRTbell Express Template Prep Kit 2.0 PacBio 100-938-900 Deposited data Genome sequence of Castilleja foliolosa GenBank JAVIJP000000000 Crystal structure of Castilleja foliolosa KAI2d15 Protein Data Bank 8TMX Recombinant DNA pGEX-4T-1 Castilleja foliolosa kai2d8 Genscript (this study) pGEX-4T-1 Castilleja foliolosa kai2d9 Genscript (this study) pGEX-4T-1 Castilleja foliolosa kai2d14 Genscript (this study) pGEX-4T-1 Castilleja foliolosa kai2d15 Genscript (this study) pGEX-4T-1 Castilleja foliolosa kai2d15 M142V M153V M157V Genscript (this study) pGEX-4T-1 Castilleja foliolosa kai2i1 Genscript (this study) Software and algorithms ZEN 3.7 Zeiss Hifiasm 0.16.0 https://github.com/chhylp123/hifiasm Cheng et al. 27 Helixer v0.3.3 https://github.com/weberlab-hhu/helixer Stiehler et al. 28 InterProScan 5.55-88.0 https://github.com/ebi-pf-team/interproscan Jones et al. 29 EggNOG-mapper 2.1.12 https://github.com/eggnogdb/eggnog-mapper Cantalapiedra et al. 30 SynMap2 https://genomevolution.org/SynMap.pl Haug-Baltzell et al. 31 R 4.2.0 https://www.r-project.org/ R-Core-Team 32 MEGA11 https://www.megasoftware.net/ Tamura et al. 33 XDS https://xds.mr.mpg.de/ Kabsch 34 Phenix 1.20.1 https://phenix-online.org/ Zwart et al. 35 WinCoot 0.9.8.1 https://bernhardcl.github.io/coot/ Emsley et al. 36 Section title: Escherichia coli Educational score: 4.037405014038086 Domain: biomedical Document type: Study Language: en Escherichia coli strain BL21 (DE3) cells were used for heterologous expression of Castilleja KAI2 proteins. Cells were cultured in Lysogenic Broth (LB) medium and induced with 0.1 mM IPTG at an optical density (OD600) of 0.6, followed by overnight incubation in Terrific Broth (TB) medium at 18°C. Section title: Castilleja sp. Educational score: 3.511381149291992 Domain: biomedical Document type: Study Language: en Seeds of all Castilleja species in this study were stratified on wet Whatman filter paper at 4°C in the dark for six weeks, after which they were transferred to a growth chamber maintained at 21°C under a 16-hour light/8-hour dark cycle. In GR24-treated experiments, seeds were exposed to a 1 μM concentration of GR24 5DO. Section title: Castilleja seed stratification and germination Educational score: 3.3937225341796875 Domain: biomedical Document type: Study Language: en Castilleja seeds sourced from San Diego County, California were stratified for 6 weeks on wet Whatman filter paper at 4°C in the dark. After, they were transferred for germination into a growth chamber at 21°C and a 16 h light cycle. For GR24-treated seeds, a 1 μM concentration of GR24 5DO DO (StrigoLab, Turin, Italy) was used. Section title: Microscopy Educational score: 4.121435165405273 Domain: biomedical Document type: Study Language: en Castilleja seedlings were directly observed on Whatman filter paper without any fixation. Images were captured using a Zeiss Axio Zoom.V16 microscope in brightfield mode, employing a 2x optovar and a 0.63x camera adapter. Images were acquired at a resolution of 2464 x 2056 pixels. Adjustments for brightness and contrast were applied using the ZEN 3.7 software (Carl Zeiss AG) to enhance clarity and detail. To assess cell viability, we used Rhodamine 123, which selectively stains mitochondria in living cells. 37 The plants were submerged for 30 minutes in a Rhodamine 123 staining solution, prepared to a final concentration of 0.02% (w/v). Root structures and cells were then examined using a Leica Stellaris 8 confocal microscope. Section title: Genomic DNA isolation Educational score: 3.311570882797241 Domain: biomedical Document type: Study Language: en Genomic DNA was isolated using the Nanobind plant nuclei kit (PacBio). 15 μg of genomic DNA was isolated from 2 g of a single Castilleja foliolosa flower. Section title: Genome sequencing and assembly Educational score: 4.129248142242432 Domain: biomedical Document type: Study Language: en Sequencing libraries were prepared using the PacBio SMRTbell Express Template Prep Kit 2.0, following the manufacturer’s guidelines. Sequencing was conducted on the PacBio Sequel IIe system. The raw HiFi reads generated from the PacBio Sequel IIe platform were assembled into contigs using Hifiasm. 32 Default parameters were used for the assembly, and quality control metrics were examined to ensure the fidelity of the assembly. Section title: Gene prediction and annotation Educational score: 3.6705100536346436 Domain: biomedical Document type: Study Language: en Castilleja foliolosa gene prediction was performed using HELIXER 38 and functional annotation was carried out using InterProScan 39 and EggNOG-mapper. 33 Section title: Genomic synteny analysis and phylogeny Educational score: 4.185871124267578 Domain: biomedical Document type: Study Language: en Pairwise synteny analyses were done using SynMap 34 with a minimum number of aligned pairs set to 20. The 'tidyverse' package 35 in R 36 was used to transform aligncoords files: The data file was imported, lines commencing with '#' were filtered out, and chromosome IDs were extracted from the data. Genome fasta files were transposed into segment data files using the 'Biostrings' package 40 : Lengths of the sequences were computed and a data frame containing chromosome names, start positions, and end positions were created. Link and segment data were adjusted to the actual genome sizes by applying scaling factors. The 'OmicCircos' package 41 was then used to generate a Circos plot, and links indicating associations between segments were added. Section title: Genomic synteny analysis and phylogeny Educational score: 3.8531787395477295 Domain: biomedical Document type: Study Language: en A phylogenetic tree of KAI2 protein sequences was built using the Maximum Likelihood method and JTT matrix-based model. The tree with the highest log likelihood is shown. The final tree was displayed using MEGA11. 42 Section title: Molecular cloning Educational score: 4.0648674964904785 Domain: biomedical Document type: Study Language: en For heterologous protein production, all genes were synthesized codon-optimized for Escherichia coli and cloned into a pGEX 4T1 expression vector to produce GST fusion proteins. Genes were designed to encode an N-terminal site for HRV3 protease, leaving two amino acids (Gly-Pro) as N-terminal cloning artifact. Section title: Protein expression and purification Educational score: 4.273484706878662 Domain: biomedical Document type: Study Language: en Escherichia coli strain BL21 (DE3) cells were transformed and subsequently cultivated overnight in Lysogenic Broth (LB) medium. A fresh culture was initiated in Terrific Broth (TB) medium the next day using a 1:100 dilution. Cultivation was maintained at 23°C until an optical density (OD 600 ) of 0.6 was reached, after which induction was performed with 0.1 mM isopropyl β-D-1-thiogalactopyranoside (IPTG) at 18°C and left overnight. The cells were harvested, and lysis was achieved through sonication. Centrifugation at 75,000 g for 45 minutes was then used to separate cell debris, after which the supernatant was transferred onto a glutathione affinity column. This column was flushed with a buffer of 50 mM TRIS-HCl, 150 mM NaCl, 5% glycerol, and 1 mM TCEP, with a final pH of 7.7, until no protein flow-through was detected by UV absorption. HRV3 protease was subsequently introduced to the column and left overnight. The cleaved target protein was eluted using the same buffer and further purified to homogeneity through size exclusion chromatography on a GE Healthcare HiLoad 16/60 Superdex 75 column, prepared with 20 mM TRIS-HCl, 30 mM NaCl, and 1 mM TCEP-HCl buffer, with a final pH of 7.7. The proteins were concentrated to a minimum of 10 mg/ml and flash-frozen in liquid nitrogen. Section title: Differential scanning fluorimetry Educational score: 4.129734992980957 Domain: biomedical Document type: Study Language: en Differential scanning fluorimetry experiments were performed in a CFX Opus 384 system (Biorad). Sypro Orange (Life Technologies) was used as reporter. 10 μg of protein was heat-denatured using a linear 25°C to 95°C gradient at a rate of 1°C per minute. The denaturation curve and its derivative were obtained using the CFX manager software. Reaction mixtures were prepared in 20 μl volumes in triplicates in 384 well white microplates. Reactions were carried out in 20 mM TRIS-HCl, 30 mM NaCl, 1 mM TCEP-HCl, final pH 7.7. A final 3x concentration of Sypro Orange was used. Section title: Protein crystallization and structure solution Educational score: 4.357241630554199 Domain: biomedical Document type: Study Language: en Crystals of Castilleja foliolosa KAI2d15 were obtained from a 200 nl sitting drop, prepared with a protein-to-reservoir ratio of 1:1 and a chemical composition of 0.9 M diammonium phosphate, 0.1 M sodium acetate at pH 4.5, and 0.01 M barium chloride. To these crystals, 1.8 M sodium malonate was applied as a cryo-protectant. X-ray data were collected at beamline 8.2.2 of the Advanced Light Source at Lawrence Berkeley National Laboratory and subsequently processed with XDS. 43 The structure of KAI2d15 was solved with Phaser through molecular replacement, utilizing chain A of PDB structure 4IH1 ( Arabidopsis thaliana KAI2) as the model. For the calculation of R-free, five percent of the data were flagged. Initial models were constructed using AutoBuild and refinement of the models was performed using phenix.refine, all of which are part of the Phenix suite. 44 Manual correction and finalization of these models were accomplished with Coot. 45 Section title: Quantification and statistical analysis Educational score: 3.735564947128296 Domain: biomedical Document type: Study Language: en Data for seed germination, DSF destabilization, and Michaelis-Menten kinetics are presented as mean values with standard deviation (SD) across three or more independent experiments and calculated with R for seed germination and with Origin (OriginLab) for DSF and Michaelis-Menten kinetics. Detailed sample sizes (n) and specific conditions are noted in each figure legend, along with any variation among replicates, with error bars representing the standard deviation where applicable. | Study | biomedical | en | 0.999997 |
PMC11697716 | Section title: Introduction Educational score: 4.328815460205078 Domain: biomedical Document type: Study Language: en Lesions in the primary visual cortex (V1) trigger degeneration and volume loss in the lateral geniculate nucleus (LGN), both in human and non-human primates . The degeneration involves projection neurons in the magno- (M), parvo (P), and koniocellular (K) neurons, as well as corticogeniculate fibers . However, amount of degeneration may vary according to the species, lesion extent and survival time . V1 lesions in primates also cause cortical blindness, a condition that may reflect not only the immediate loss of cortical tissue, but also the secondary loss of LGN and retinal cells . Section title: Introduction Educational score: 4.3517889976501465 Domain: biomedical Document type: Study Language: en Despite degeneration and volume loss caused by the lesion, there are a number of surviving neurons in the LGN, offering the potential for plasticity and recovery . One recently revealed form of plasticity are changes in protein expression in the surviving neurons . Neurons in the normal LGN show specificity in their expression of calcium-binding proteins, with M and P neurons exclusively expressing parvalbumin (PV) and K neurons expressing calbindin-D28K . In animals with long-term V1 lesions, this specificity is disrupted with many M and P neurons co-expressing CB and PV . It has been found that some of the neurons undergoing this neurochemical change form projections to the middle temporal area (area MT) , one of the key cortical areas hypothesized to mediate residual visual capacities following V1 lesions . These findings reinforce the view that surviving LGN neurons may play a role in the residual visual abilities that remain within scotomas associated with V1 lesions. Section title: Introduction Educational score: 4.186740875244141 Domain: biomedical Document type: Study Language: en Retrograde degeneration following V1 lesions is likely to be a gradual process . However, data on the exact pace of the degeneration remains sparse, particularly in the first weeks after V1 lesions. In addition, little is known about the time course of changes in calcium-binding protein expression. Here we address this knowledge gap by studying the cellular anatomy of the LGN in marmoset monkeys in the first weeks or months following V1 lesions. Marmosets are non-human primates which have been gaining prominence as a translational model for studies of human biology and disease . Understanding the rate of progress of post-injury degenerative processes may provide important clues for future work aimed at minimising cell loss, and potentially greater preservation of residual visual abilities. Section title: Subjects Educational score: 3.768810510635376 Domain: biomedical Document type: Study Language: en The present study was performed in a cohort of 21 marmoset monkeys ( Callithrix jacchus ), of which 14 received a unilateral V1 lesion in adulthood and 7 were non-lesioned controls. The animals were of either sex as detailed in Table 1 . Eleven of these animals (4 lesioned, 7 controls) were part of other experiments involving fluorescent tracer injections or electrophysiology experiments, not reported here. Their health condition and well-being were monitored throughout the experimental period. The experiments were conducted based on the Australian Code of Practice for the Care and Use of Animals for Scientific Purposes. All experiments were approved by the University Animal Ethics Experimentation Committee. Section title: V1 lesions Educational score: 4.049195289611816 Domain: biomedical Document type: Study Language: en The V1 lesion surgery was conducted following an updated procedure based on the technique introduced by Rosa et al. . This procedure involves an occipital lobectomy along a vertical plane across the border between V1 and the second visual area , resulting in a complete loss of the representation of the visual field up to 10° eccentricity along the vertical meridian, and 20–30° along the horizontal meridian. Reconstructions of lesions and visual field defects created with this procedure have been reported previously . Section title: V1 lesions Educational score: 4.242086887359619 Domain: biomedical Document type: Study Language: en The animals were pre-medicated with oral meloxicam (Metacam; Boehringer Ingelheim, 0.1 mg/kg, i.m) and cephalexin (Ibilex; Alphapharm P/L, 30 mg/kg, i.m) 24 hours before the surgery. Atropine (Atrosite; Ilium, 0.2 mg/kg) was administered 30 minutes before anaesthesia, which was accomplished by inhalation of isoflurane (Isorrane; 4–5% in oxygen, Baxter). Dexamethasone (Dexason; Ilium, 0.3 mg/kg, i.m) was also administered. During the surgery, the animals were positioned in a modified stereotaxic head holder while their heart rates, body temperatures, and body oxygenation levels (PO 2 ) were continually monitored. The anaesthetic condition was adjusted continuously (isoflurane, between 2 and 5%) to ensure the animals showed no spontaneous muscle activity and had no withdrawal reflexes. After craniotomy and durectomy the occipital pole was removed using a fine-tipped cautery, following a vertical excision along a plane extending from the dorsal surface of the occipital lobe to the cerebellar tentorium, across its entire mediolateral extent. After the removal of tissue, the resulting cavity was filled with haemostatic microspheres (Arista AH, BARD Davol Inc.) until the bleeding stopped. The surface of the wound was covered with ophthalmic film (Gelfilm, Pfizer Inc.), and the cavity was filled with Gelfoam (Pfizer Inc.). The skull flap was repositioned and secured with cyanoacrylate (Vetbond, 3M), followed by skin suture with polyglactin thread (5-0 Vicrly, Johnson & Johnson). The animals then were placed in an infant incubator (Atom Medical) for recovery and reintroduced to the home cage after recovery of mobility. During recovery, postoperative analgesia (oral meloxicam 0.05 mg/kg for adults, 3 d) and antibiotic (oral cephalexin 30 mg/kg, 5 d) was given. The animals demonstrated normal movement abilities including precise grasping, holding, jumping between branches, and obtaining food without assistance already on the day following surgery, and throughout the recovery period. With the exception of animals tested at very short survival times (<1 month), they were kept within family groups and lived in large cages with access to both indoor and outdoor environments. The short survival animals were kept in a facility that allowed close monitoring, in visual and auditory contact with other marmosets. Section title: Tissue processing Educational score: 4.210128307342529 Domain: biomedical Document type: Study Language: en Following variable survival periods ( Table 1 ) the animals were anaesthetised with Alfaxan (Ibilex, 30mg/kg i.m.) and then overdosed with a pentobarbitone sodium injection (100 mg/kg i.v.). Following cardiac arrest, they were perfused with 0.1 M heparinised phosphate buffer (PB; pH 7.2) and 4% paraformaldehyde (PFA) in 0.1 M PB. The brain was removed and post-fixed for 24 hours in the same solution, after which cryoprotection was performed by immersion in 4% buffered PFA solutions with increasing concentrations of sucrose (10%, 20% and 30%). The brain was then snap-frozen and cut into 40 μm coronal sections using a cryostat . Table 1 Experimental details for all subjects. Table 1 Subject (Sex) Survival (∼months) Shrinkage ratio (% ipsi/intact) Age at lesion (∼months) Age at perfusion (∼months) Analysed LGN WA9(M) 39 50.84% 19 58 Both WA14 a (F) 31 52.30% 25 57 Both WA13 a (M) 28 68.61% 29 57 Both WA16 b (M) 23 57.36% 32 55 Both WA15 a (F) 12 43.17% 26 38 Both WA25(F) 6 71.53% 26 32 Both WA22(F) 3 85.11% 42 45 Both WA23(F) 3 85.98% 37 40 Both WA20(M) 2 75.87% 36 38 Both WA21(F) 2 84.02% 44 46 Both WA27(M) 1 78.83% 39 40 Both WA32(F) 2 weeks 91.54% 30 30 Both WA24(F) 3 days 96.65% 32 32 Both WA26(M) 2 days 101.58% 45 45 Both CJ227 a (M) – 102.51% – 37 Both CJ217 a (M) – 99.37% – 34 Both CJ200 a (F) – 98.39% – 44 Both F1741 a (F) – – – 42 Right CJ174 b (F) – – – 32 Right CJ170 b (M) – – – 29 Right CJ167 b (F) – – – 28 Right a Animals that received fluorescent tracer injections for other projects. b Animals that participated in electrophysiology experiments for other projects. CJ217 and CJ227 were only used for volume analysis. (M) Male; (F) Female. Section title: Tissue processing Educational score: 4.076173782348633 Domain: biomedical Document type: Study Language: en For NeuN staining, every fifth section was washed in a PB solution (0.1 M). The sections were incubated with a blocking solution (0.3% Triton-X100 and 10% horse serum in 0.1 PB) for 1 h at room temperature, and then treated with NeuN primary antibody for 46–48 h at 4 °C. This was followed by incubation with biotinylated horse anti-mouse IgG secondary antibody for 30 min at room temperature. The sections were then incubated with ABC reagent (100μl of solution A and 100μl of solution B in 5 ml of 0.1M PB) for 30 min at room temperature. After incubation, sections were stained with DAB substrate working solution for 30 min at room temperature, followed by three washes with PB (0.1M). The mounted sections were dried for 48 h before being coverslipped. Section title: Tissue processing Educational score: 4.150692462921143 Domain: biomedical Document type: Study Language: en For fluorescence staining of calcium-binding proteins another series of sections (1 in 5) was incubated with blocking solution for 1 h at room temperature, followed by 46–48 h incubation in primary antibodies for CB and PV . The secondary antibodies [1:600; Alexa Fluor® 488 and Alexa Fluor® 647 ] were applied for 60 min at room temperature, followed by coverslip using antifade mounting medium (Vectashield, Vector Laboratories). These antibodies have been validated previously and here we have provided further evidence in Extended Data Fig. 1 . Fig. 1 Design of sampling for stereological analysis. A–M: NeuN-stained coronal sections from WA25 covering the extent of lateral geniculate nucleus , on which location and number of sampling frames (100 × 150 μm 2 ) are shown. A represents the most posterior part of LGN. N: Inset in E. Red dashed lines separate the lesion projection zones (LPZ) from the rest of LGN. The boundaries of LPZ is determined according to cell size and the variation in neuronal density. The counting frames were placed in a radial dimension covering the different cellular layers in LGN. Evidence of no cellular staining in the absence of NeuN primary antibody is shown in the supplementary Fig. 1 . Scale bar: 1mm. Fig. 1 Section title: Quantification and statistical analysis Educational score: 4.168166160583496 Domain: biomedical Document type: Study Language: en For NeuN-stained brain sections, slides were scanned with an Aperio Scanscope AT Turbo microscope (Leica Biosystems) at × 20 magnification under the resolution of 0.50 μm/pixel, and analysed using Aperio Image Scope software. Estimation of volume was done using Cavalieri estimator based on the area of LGN in equally spaced sections throughout the anteroposterior extent of this nucleus . For neuronal density, counting frames (150 × 100μm 2 ) were placed systematically on each LGN section covering both degenerated and undegenerated sectors. In each section, 2–13 of counting frames were placed in a radial direction across all layers . Only neurons with clear staining were counted, regardless of shape. Every neuron that was fully located inside the frame or that intersected the top or right edges was included. Data of all sections were combined for analysis. The cell counts were converted to densities (cells/mm 3 ) by taking into consideration the section thickness and a shrinkage factor of 0.801 . Section title: Quantification and statistical analysis Educational score: 4.069079399108887 Domain: biomedical Document type: Study Language: en The fluorescence immunostained sections were scanned using confocal microscopes (Nikon C1 invert, 20x magnification, filters 488, 647) and analysed with ImageJ software (Fiji, USA). The LGN was sampled in fixed sized square frames (638 × 638μm 2 ) from the middle sections of the LGN, where the placement of the counting frames covered most of LGN . Only neurons with clear fluorescent signal were counted using the cell counter plug-in. For analysis of CB expression in M and P neurons, we manually marked all PV-immunoreactive neurons within the M and P layers of LGN. We then counted CB-expressing neurons from the population of marked neurons, and calculated the percentage of double-labelled neurons. All statistical analysis was performed using Prism 9 (GraphPad software, USA). Data were analysed using student's t-test, one- or two-way ANOVA and linear regression where applicable and presented as mean ± standard error of the mean (SEM). Statistical results with a p value < 0.05 were considered statistically significant. Section title: V1 lesion triggers neuronal loss in the LGN within a month Educational score: 4.349313735961914 Domain: biomedical Document type: Study Language: en In the animals perfused 2–3 days post lesion, NeuN staining of the LGN ipsilateral to the lesion revealed no changes in volume, lamination and neuronal size/density in comparison with the contralateral LGN . In all other cases a pale staining region corresponding to the lesion projection zone (LPZ; the sector of LGN that corresponds topographically to the V1 lesion) was obvious in the ipsilesional LGN, similar to previous observations . Higher magnification views of neurons within and outside the LPZs are shown in Fig. 4 A, showing that the pale staining regions were characterised by obvious reduction in neuronal density. In one animal (WA32), which survived only two weeks after V1 lesion, the LPZ was only partially evident, particularly at higher magnifications, by virtue of morphological changes such as reduced cell size and the loss of definition in the contours of neuronal nuclei . In this case, the volume of the LGN ipsilateral to the lesion was 8% lower than that on the unaffected side, which slightly surpasses the typical variability in LGN volume estimates between hemispheres, further indicating an ongoing degenerative process. Fig. 2 No visible cellular loss is observed in the lateral geniculate nucleus (LGN) three days (A) or two weeks (B) after lesion in the primary visual cortex (V1). Top: NeuN-stained LGN in the lesioned (left) or intact hemispheres (right). Dashed lines show layer boundaries. PE: parvocellular external layer, PI: parvocellular internal layer, K3: Koniocellular 3, MI: magnocellular internal layer, ME: magnocellular external layer, K1: Koniocellular 1. Scale bar: 1 mm. Black arrows point to the limits of degenerated zone in B. Bottom: Boxed areas in the expected lesion projection zone (parvocellular layers) and a corresponding region of the contralateral hemisphere are shown in higher magnification. Scale bar = 100μm. Fig. 2 Fig. 3 Lesions of the primary visual cortex (V1) trigger retrograde degeneration in the lateral geniculate nucleus (LGN). A: Representative images of NeuN-stained coronal sections through the LGN (interaural +4.80mm), obtained from four animals with different post-lesion survival times. In all cases the LGN ipsilateral to the V1 lesion shows a well-defined lesion projection zone (LPZ, identified by dashed line/asterisk), while the contralateral LGN shows normal lamination and shape. Scale bar: 1mm. Fig. 3 Fig. 4 Lesions of the primary visual cortex (V1) cause significant neuronal loss in the lateral geniculate nucleus (LGN) within the first month. A: Representative images from the lesion projection zone (LPZ) and non-LPZ regions in control (CJ167), short survival (WA27) and long survival (WA13) cases. Scale bar = 100 μm. B–D: Mean ± SEM of neuronal density of LGN for the short and long survival animals in LPZ (B) and non-LPZ (C) as well as control animals (D). Different post-lesion survival times are identified with different symbols in the short survival group (two weeks to 6 months post lesion). Density values for the case of two weeks survival (WA32) are marked on A and B for comparison purposes, but they were not included in the averaging and statistical analysis. E: Variability of neuronal density across LGN layers for all cases. Each circle represents a sampling frame as depicted in Fig. 1 . Small lines represent mean, also indicated in B-D. Fig. 4 Section title: V1 lesion triggers neuronal loss in the LGN within a month Educational score: 4.126160621643066 Domain: biomedical Document type: Study Language: en For quantitative analysis, the cohort of animals was divided into short survival (<6 months, excluding animals that only survived 2–3 days) and long survival (12–39 months) groups, the latter corresponding to time points already explored . As shown in Fig. 4 B, the neuronal density in the LPZs dropped to nearly half of the values observed outside the LPZs in the same animals, or in control animals. This drop was evident in all cases that survived at least 1-month post lesion, indicating a rapid neuronal loss following V1 lesion. In contrast, in the case with a 2-week survival the neuronal density in the LPZ was similar to the values observed outside the LPZ or in control animals , indicating that the apoptotic process had not been completed. This is despite the surviving neurons displaying more variable degrees of size, shape and definition compared to the healthy-looking neurons of the equivalent area in the contralateral LGN , suggesting initial stages of degeneration. Density values for this case are shown in Fig. 4 for comparison purposes, but were not included in the statistical analyses below. Section title: V1 lesion triggers neuronal loss in the LGN within a month Educational score: 4.142018795013428 Domain: biomedical Document type: Study Language: en The observed neuronal loss was similar among all cases in the short survival group . Comparison with those in the long survival group also did not reveal any differences for neuronal density in the LPZ, indicating no further degeneration [ Fig. 4 B and C, two-way ANOVA; survival time: F (1, 20) = 2.15, p = 0.16, zone: F (1, 20) = 52.71, p < 0.0001, interaction; F (1, 20) = 0.0027, p = 0.96, post hoc; LPZ vs. non-LPZ; short survival , long survival (18.59 ± 0.54 vs. 35.02 ± 1.03 × 10 3 /mm 3 , p < 0.001)]. The mean neuronal density outside the LPZ was similar to that found in the LGN of non-lesioned control animals, both in the short and long survival groups [ Fig. 4 C and D, One-way ANOVA, F (2, 14) = 0.49, p = 0.62), control; 39.65 ± 1.90 × 10 3 /mm 3 ]. Neuronal densities acquired from all sampling frames in each LGN has been shown in Fig. 4 E, suggesting a variable neuronal density in different LGN layers, although this variability remained relatively similar across cases. Section title: LGN shrinkage advanced with the time after V1 lesion Educational score: 4.157832145690918 Domain: biomedical Document type: Study Language: en The average LGN volume loss (ratio of ipsilesional LGN volume to contralesional LGN volume) was more extensive in the long survival group compared to the short survival group . To account for the possibility of variations in lesion sizes, we ran a separate analysis comparing the percentage loss of volume in the LPZ and non-LPZ regions, compared to the contralesional LGN volume. This analysis showed that the difference between the two groups originates mainly from changes in the LPZ volume . Although the analysis of non-LPZ volume shown in Fig. 5 C indicates some variability across cases, the results did not reach statistical significance (non-LPZ; 36.52 ± 6.12 vs. 48.40 ± 2.919%, p = 0.15). In summary, the result indicates a significantly smaller volume loss in the short survival group. Fig. 5 Lateral geniculate nucleus (LGN) volume loss correlates with the post-lesion survival time. A–C: Mean ± SEM of volume of the LGN for animals with short (2 weeks–6 months, n = 7) and long (12–39 months, n = 5) post-lesion survival period. Volume is presented as percentage of ipsilateral LGN (A) or its sectors, lesion projection zone (LPZ, B) and non-LPZ(C) compared to the contralateral LGN. Different post-lesion survival times are identified with variable symbols in the short survival cases. ∗∗p < 0.01. D–I: Percentage mean volume of LPZ (D, F, H) or non-LPZ (E, G, I) sectors are plotted against the post-lesion survival time. Data obtained in the short survival and long survival groups are shown separately (D–G) or combined (H–I). R2 represents the significance levels for the slopes of simple linear regressions for each condition. Fig. 5 Section title: LGN shrinkage advanced with the time after V1 lesion Educational score: 4.152345657348633 Domain: biomedical Document type: Study Language: en To further understand the differences in volume loss in relation to survival times, we plotted percentage volume (i.e. the ratio of the volumes in the LPZ vs. contralesional LGN) against the survival time post-lesion in Fig. 5 (D–I). A negative linear correlation was observed for LPZ volume . When the correlations were conducted separately for the short and long survival group, only the short survival group demonstrated a statistically significant negative correlation . This finding is consistent with the previous study that the shrinkage of LGN stabilised within six to seven months following V1 lesions . The normalised volume of non-LPZ (as compared to contra-lesion LGN), on the other hand, did not show statistically significant changes in both short and long survival groups . Thus, the results indicate a substantial rapid loss of neurons occur first, followed by a gradual shrinkage of the LGN after lesion, and argue against differences in lesion extent being a confounding factor. Section title: Calbindin positive M and P neurons exist as early as two weeks post lesion Educational score: 4.292191982269287 Domain: biomedical Document type: Study Language: en Previous studies have demonstrated that, in addition to degeneration, V1 lesions elicit neurochemical changes in the LGN M and P neurons . In particular, these neurons, which normally only express PV , also show co-expression of CB, including in M neurons projecting to area MT . Here we explored the timing of CB expression in M and P neurons following V1 lesions. The CB positive neurons were quantified from populations of PV-expressing neurons (M and P) in the non-LPZ in the short survival group. This confirmed the presence of CB in M and P cells in all cases, ranging from 2 weeks to 6 months post-lesion . Example images of CB expression in M and P neurons are shown in Fig. 6 A–B. Regression analysis revealed a trend towards greater CB expression in M and P neurons with the survival time, although this did not reach a statistically significant level . While degeneration is exclusive to the ipsilesional LGN, a minimum of about 11% CB co-localisation with PV was also detected in the contralateral LGN , confirming that this neurochemical change triggered by the unilateral lesion occurs in both hemispheres . The average values obtained from all lesioned animals showed that the proportion of CB expressing M and P neurons was significantly higher in the ipsilesional LGN . Lack of CB expression in M and P cells in nonlesioned animals is indicated as an average of three cases in Fig. 6 D. These data, obtained using the same methodology, have been published previously as individual cases . Higher percentage of M neurons showed CB expression in comparison with P neurons only in the contralateral LGN [ Fig. 6 E; two-way ANOVA; interaction, F (1, 102) = 0.24, P = 0.62; hemisphere, F (1, 102) = 3.19, P = 0.077; Cell type, F (1, 102) = 11.03, P = 0.0012, post hoc: M vs. P: Ipsi; 27.54 ± 1.94 vs. 21.94 ± 2.09, P = 0.17, Contra: 24.98 ± 2.43 vs. 17.41 ± 1.24, P = 0.048]. Fig. 6 Calbindin (CB) immunoreactivity in parvalbumin (PV)-expressing neurons of lateral geniculate nucleus (LGN) is present after two weeks following lesions of the primary visual cortex (V1). A: Representative images showing CB expression in PV-expressing magnocellular (M) and parvocellular (P) neurons for 3 animals which survived two weeks (WA32), three (WA22) and six (WA25) months post-lesion. Yellow arrows point to individual neurons expressing both CB and PV. Scale bar: 100μm. B: Locations of individual images within the LGN. ME: magnocellular external layer, MI: magnocellular internal layer, PE: parvocellular external layer, PI: parvocellular internal layer. C: Mean percentage of CB expression in the ipsilesional M and P neurons is plotted against post-lesion survival time. R 2 indicates the significance level for the slope of a simple linear regression. D: Percentage mean ± SEM of CB expression in M and P neurons of the LGN for control and lesioned cases (the latter shown as individual cases and also averaged). Black circles represent individual sections analysed. E: Averaged data from lesioned cases (shown in D) is indicated separately for M and P layers. ∗p < 0.05. Evidence of no cellular staining in the absence of primary antibodies for CB and PV is shown in Supplementary Fig. 1 . Fig. 6 Section title: Discussion Educational score: 4.204062461853027 Domain: biomedical Document type: Study Language: en The present study quantified changes in the structure and neurochemistry of the marmoset monkey LGN across an extended time span following V1 lesions. Our study builds on the prior knowledge of degenerative changes in primate LGN, by employing quantitative, comprehensive assessment of neuronal density, volume and neurochemistry. Using specific methods for the labelling of neurons, we found that the vast majority of the changes in neuronal density in the LPZ occurred between 14 and 30 days post lesion, with no further changes up to 3 years post lesion. However, the shrinkage of the LPZ happened according to a slower timescale, not being completed until 6 months post lesion. In parallel to these degenerative changes, we found that CB expression could be detected in surviving M and P neurons as early as 2 weeks post lesion. Section title: Neuronal loss in the LGN Educational score: 4.325351715087891 Domain: biomedical Document type: Study Language: en V1 lesion induced fast retrograde degeneration, which resulted in a sharp decrease of neuronal density in the LGN within just 1 month of the lesions. The fast nature of degeneration is in agreement with previous studies in other primate species , which used the Nissl stain to assess neuronal loss. In squirrel monkeys, neuronal degeneration is reported to be completed within 42 days, with early signs of retrograde degeneration being evident only 5–8 days after lesions . This time course is compatible with that suggested by our data, where no cell loss was detected 3 days after lesion, while there were indications of changes in cell morphology and size after 2 weeks, possibly as signs of degenerative process. Despite changes in morphologies, our quantification suggests that there is no overt neuronal loss at this time point. The small variability in the estimates of neuronal density in the LPZ among cases with survival times of a month or more indicates that the degeneration process has been largely completed within a month, supporting previous data in macaque monkeys , who reported completion of degeneration within 3–6 weeks. Section title: Neuronal loss in the LGN Educational score: 4.2016191482543945 Domain: biomedical Document type: Study Language: en The present study, employing quantitative assessment of neuronal density with a specific neuronal marker, extends previous knowledge with additional significant details, over a wider time scale, and to a different primate species (marmoset). In the context of previous literature, these results are significant in two ways. First, they demonstrate that the time course of degeneration is similar despite large differences in brain size (and hence axonal length) among primate species. This species similarity indicates that a comparable time course is likely to apply to the human brain. Second, they identify a time window during which possible future interventions to reduce neuronal loss in the LGN need to apply. Long-term occipital lesions cause loss of function not only due to the direct loss of V1 cortex, but also subsequent degenerative changes in the LGN and retina . Preventing or minimising the secondary losses in the afferent visual pathway may be relevant for future therapeutic interventions aimed at retaining or improving residual vision. Section title: Neuronal loss in the LGN Educational score: 4.285476207733154 Domain: biomedical Document type: Study Language: en Previous studies in macaque have suggested a potentially more significant cell loss in the LGN following V1 lesions, compared to observations in marmoset . In this context, the variability in lesion sizes, involving different parts of extrastriate visual cortex, can significantly contribute to variations in cell loss . In the present study, the lesions consistently damaged the foveal and near-peripheral representations of V1 in one hemisphere, largely avoiding V2 except for near the boundary with V1 . The difference may also be partially due to technical differences, including the use of Nissl staining in earlier studies, rather than the more specific NeuN stain, and, in some cases, qualitative assessment . The possibility also exists that there are differences in the pattern of projections from LGN neurons to extrastriate areas between marmosets, macaques and humans, which could affect neuronal survival by allowing preservation of different numbers of synaptic targets outside the lesioned zones. However, currently there is no evidence of such differences , warranting further studies. Our observation of a variable distribution of neuronal loss across LGN , is partly reflective of the natural variability as we have reported previously , however it may also reflect differential neuronal loss across LGN layers that requires further studies. Section title: Loss of LGN volume Educational score: 4.222019195556641 Domain: biomedical Document type: Study Language: en Atrophy of the LGN is a critical pathological indication for V1 lesions which can be quantified with non-invasive brain imaging . Whereas volume reduction is clearly influenced by neuronal loss, these two aspects of degeneration can occur independently. For example, volume changes without concomitant loss of neuronal cell bodies have been observed in the pulvinar complex following V1 lesions, an observation that has been interpreted as indicating that volume reduction was likely due to changes in the neuropil . Section title: Loss of LGN volume Educational score: 4.128472805023193 Domain: biomedical Document type: Study Language: en In the present study, the volume loss in the LGN ipsilateral to the lesion increased with the survival time, despite the level of neuronal loss being similar across all cases. This observation was normalised for the lesion size (a factor which is likely to affect LGN shrinkage) by separate estimation of percentage volume loss for LPZ and non-LPZ. This correlation with survival time was not observed among long survival animals. This is consistent with previous observations that volume loss in the marmoset LGN does not progress beyond 6–7 months post lesion. Section title: Loss of LGN volume Educational score: 4.4608154296875 Domain: biomedical Document type: Study Language: en The delayed time scale for volume loss, compared to neuronal degeneration, may be due to the time required for debris removal , neuropil loss, or even remodelling of the capillary bed due to reduced energy requirements following apoptosis of LGN neurons. Moreover, cortico-geniculate axons and terminals fill much of the space between LGN neurons , and their loss may also contribute to volume changes. Although evidence suggests that the time course and magnitude of retrograde and Wallerian (anterograde) degeneration are similar , there may be differences due to the differential site of injury along the axons or heterogeneity of axons and their compartmentalisation . Although it has been reported that early signs of cortico-geniculate terminal degeneration precede the retrograde degeneration of LGN neurons in squirrel monkeys , the biological complexity of degenerative processes may create difficulty in pinpointing the precise timing of events. What is clear is that the physical collapse of LGN volume is a more prolonged process than neuronal death. Section title: Expression of CB in surviving neurons Educational score: 4.188239097595215 Domain: biomedical Document type: Study Language: en Recent studies have shown that neurochemical changes are part of long-term plastic changes in the primate LGN following V1 injury . Under normal conditions neurons in the M and P layers only express PV . Following V1 lesions they also co-express CB, a fact that we find evident even two weeks after lesion. However, the percentage of M and P neurons expressing CB following short survival times is lower (17–27%) than that observed after longer survival times , further emphasising the gradual nature of the emergence of CB expression in M and P neurons. Section title: Expression of CB in surviving neurons Educational score: 4.415736198425293 Domain: biomedical Document type: Study Language: en The present observations are in line with previous data that indicate changes in the neurochemistry of M and P neurons also occur in the LGN of the hemisphere contralateral to the lesion . It has been suggested that V1 lesions could lead to reduced cortical feedback onto surviving LGN neurons , creating imbalanced activation of these neurons by the retina, which in turn would trigger CB expression . Underpinning this assumption, M neurons, with the most significant CB overexpression after V1 lesions , have larger than normal receptive fields and the least degeneration of their retinal afferents . Moreover, the more prevalent CB expression in M cells may suggest their higher potential to form new connections to the cortex . CB expression has been highlighted as a protective mechanism linked to neuronal resilience under stress . Thus, concomitant with the ongoing degeneration in LPZ, the neurons in non-LPZ undergo neurochemical changes that may prepare them for better survival, or regenerative processes . Indeed, our observations are consistent with this hypothesis, as alterations in neurochemistry occur prior to the onset of neuronal loss. As recently demonstrated, the neurochemical change involves remodelling of the projections of M neurons, which form projections to extrastriate cortex . Whether the emergence of the CB expression in M/P neurons within the first few months after lesion coincides with the process of remodelling their projection to extrastriate areas remains to be tested. Section title: Expression of CB in surviving neurons Educational score: 4.1819658279418945 Domain: biomedical Document type: Study Language: en Changes in the neurochemistry of projection neurons, including expression of GABA , might lead to better survival rates. We have also previously shown that after adult V1 lesions the percentage of GABAergic neurons is increased to almost sevenfold in the LPZ of LGN, suggesting that the cell loss due to retrograde degeneration is more prominent among projection neurons . The progressive CB expression among projection neurons after lesion suggests that other neurochemical changes may also be linked with survival time, and thus a differential ratio of surviving excitatory neurons to interneurons in the LPZ is likely to happen over time. Section title: Limitations and suggestions for future studies Educational score: 3.987405300140381 Domain: biomedical Document type: Study Language: en The present study focuses on the changes occurring in LGN following V1 lesions in young adult marmosets. However, there is evidence that the age at which injury happens could affect the extent and pace of the degeneration process . Thus, additional work focused on different stages of life is advisable in order to obtain a full picture of the effects of V1 lesions. Earlier work comparing lesions in young (2–6 weeks postnatal) and adult marmosets revealed modest physiological differences in the surviving LGN neurons . Section title: Limitations and suggestions for future studies Educational score: 4.1321797370910645 Domain: biomedical Document type: Study Language: en The extent of the damage to the extrastriate visual cortex can also influence estimates of degeneration . In the present experiments, the lesions were designed to be largely contained to V1, although involvement of parts of the second visual area near the border is inevitable. More extensive lesions resulting in damage to rostral extrastriate areas would likely result in more extensive loss due to the removal of projection targets of neurons that would otherwise survive the degeneration process. However, the few surviving neurons in the LGN continue to receive retinal projections even following complete unilateral hemispherectomies . Whether the surviving neurons following larger lesions undergo biochemical changes remains an open question. In the present study, none of the animals showed damage extending to rostral extrastriate areas such as the homologues of V4, or MT Section title: Conclusions Educational score: 4.2228851318359375 Domain: biomedical Document type: Study Language: en Our study demonstrates that the neuronal loss in the LGN proceeds rapidly in the marmoset, being largely completed within one month of V1 lesions, in agreement with previous work in other non-human primates. These findings support the view that the marmoset is a valuable animal model to study the anatomical and physiological plasticity processes involved in the aftermath of V1 lesions . At the same time, the results indicate that the volume loss and biochemical changes in the LGN are slower processes, highlighting the complexity of the processes triggered by such lesions. This information has broader implications for our understanding of traumatic brain injury and future efforts towards minimising visual loss, and promoting regenerative processes which may improve the quality of residual vision in primates, including humans. Section title: Declaration of generative AI in scientific writing Educational score: 0.8718461990356445 Domain: other Document type: Other Language: en Generative AI were not used in scientific writing of this manuscript. Section title: Funding sources Educational score: 0.9931871891021729 Domain: other Document type: Other Language: en Funding was provided by the National Health and Medical Research Council to Marcello G. P. Rosa and Nafiseh Atapour . Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Study | biomedical | en | 0.999997 |
PMC11697718 | Section title: Introduction Educational score: 4.032304763793945 Domain: biomedical Document type: Review Language: en The term asbestos refers to a group of naturally occurring fibrous minerals that are used in various industrial processes mainly in the asbestos cement, construction and engineering industries ( International Agency for Research on Cancer (IARC), 2012 ). The health risks associated with asbestos exposure depend on several factors, including the concentration of fibres in the air, the length of exposure, the type and size of the fibres . The scientific community has extensively studied the relationship between asbestos exposure and the development of respiratory diseases, including asbestosis, lung cancer, and pleural mesothelioma . In addition, the International Agency for Research on Cancer (IARC) has identified links between asbestos exposure and other types of cancer, which have been considered asbestos-related diseases (ARDs), such as pharyngeal, laryngeal, oesophageal, stomach, colorectal and ovarian cancers . Section title: Introduction Educational score: 1.2015172243118286 Domain: other Document type: Other Language: en Italy is characterized by 42 National Priority Contaminated Sites (NPCSs) in 19 out of 20 regions, which represent ongoing remediation areas of special environmental interest, acknowledged for its contamination and hazard characteristics due to different environmental matrixes . Section title: Introduction Educational score: 1.4245471954345703 Domain: other Document type: Other Language: en Alessandria province has a notable history of asbestos fibre pollution, affecting both environmental and occupational settings. Particularly, Casale Monferrato is recognised as asbestos NPCS , which includes 48 municipalities in Alessandria and surrounding areas , and it was the location of the first and largest Italian asbestos-cement manufacturing factory, known as the Eternit company, active from 1907 to 1986 . Section title: Introduction Educational score: 1.8697047233581543 Domain: biomedical Document type: Other Language: en Therefore, due to the presence of major asbestos-producing industries, Casale Monferrato has experienced a high incidence of mesothelioma from occupational exposure . Additionally, many cases of para-occupational exposure (including environmental and family exposure) are still reported today. Section title: Introduction Educational score: 1.5028313398361206 Domain: other Document type: Other Language: en As a NPCS, Casale Monferrato is characterized by a greater attention for asbestos issue by citizens and territorial associations, and represents a national model in the fight against asbestos, having banned the processing, marketing and use of any containing asbestos fibres five years before the national ban . Section title: Introduction Educational score: 1.7703912258148193 Domain: biomedical Document type: Other Language: en Despite the ban on asbestos use in Italy since 1992 under Law n. 257/92, ARDs continue to pose a public health challenge in Italy and many other regions worldwide . This is due to the silent clinical progression of ARDs and the associated health and social costs, which also impact insurance, civil and criminal sectors . Section title: Introduction Educational score: 1.1831938028335571 Domain: other Document type: Other Language: en Alessandria Local Health Authority (ASL AL) includes 192 municipalities over an area of 3679 km 2 . It is organized into seven territorial areas and four districts identified as Alessandria and Valenza, Acqui Terme and Ovada, Casale Monferrato, Novi Ligure and Tortona. Section title: Introduction Educational score: 2.155414581298828 Domain: biomedical Document type: Other Language: en In primary care, general practitioners (GPs) know the health status, family, and socio-cultural background, and sometimes the occupational fields of their patients. They are the first point of contact in the healthcare system and play a key role in early disease diagnosis, because they take a patients' extensive anamnesis, examine medical history and assess symptomatology . Section title: Introduction Educational score: 2.0511248111724854 Domain: biomedical Document type: Study Language: en In 2021, a pilot study on asbestos knowledge and awareness using a 29-item questionnaire was carried out among 28 GPs in Molise region, central Italy. The survey revealed a high perception of asbestos risk and good general knowledge among GPs, but there were gaps especially for regulatory procedures . Section title: Introduction Educational score: 1.7075111865997314 Domain: biomedical Document type: Other Language: en According to the Italian National Institute of Health (ISS), the results of this pilot study were considered valuable for planning strategies to improve GPs' awareness of this issue, with the goal of enhancing patient care . Section title: Introduction Educational score: 2.3057150840759277 Domain: biomedical Document type: Study Language: en Considering these findings, and that asbestos fibre pollution that still characterized the Alessandria area, the Research and Innovation Department (DAIRI) of Alessandria University Hospital carried out a survey aimed to assess the level of knowledge and awareness of asbestos related risks among GPs in ASL AL area, as well as their experience in diagnosing and managing ARDs, throught the administration of a validated questionnaire. Section title: Pilot phase of questionnaire validation Educational score: 1.1731597185134888 Domain: other Document type: Other Language: en A total of 280 GPs work in the Alessandria province. They are members of Territorial Assistance Equipes (EATs) establish in Piedmont region, which include GPs working in similar areas for geographical characteristics and exposure to environmental risk factors with monthly meetings. Section title: Pilot phase of questionnaire validation Educational score: 1.6308857202529907 Domain: biomedical Document type: Study Language: en The questionnaire, originally used in a previous study , was revised by expanding the number of questions in the knowledge section. Section title: Pilot phase of questionnaire validation Educational score: 1.7865687608718872 Domain: biomedical Document type: Study Language: en To validate the updated version, the questionnaire was administered to 17 GPs from both Molise and ASL AL area between June and July 2022. A digital version of the questionnaire was created using the web-based “Research Electronic Data Capture” (REDCap) platform, which complies with current privacy regulations. Section title: Pilot phase of questionnaire validation Educational score: 1.5029683113098145 Domain: other Document type: Other Language: en GPs were able to access the questionnaire on smartphones, PCs and tablets and it took about 15 min to complete. Section title: Pilot phase of questionnaire validation Educational score: 1.6399749517440796 Domain: biomedical Document type: Study Language: en All GPs filled in the questionnaire after providing their informed consent. Section title: Pilot phase of questionnaire validation Educational score: 1.3177204132080078 Domain: other Document type: Other Language: en During this phase, the digital questionnaire was also supplemented with satisfaction questions concerning ease of access, technical issues, clarity of questions and answers, and other improvement suggestions. Section title: Validated questionnaire Educational score: 1.561627745628357 Domain: biomedical Document type: Other Language: en The validated questionnaire was presented to GPs in ASL AL during 26 EATs meetings held between September 2022 and January 2023. Section title: Validated questionnaire Educational score: 2.3887503147125244 Domain: biomedical Document type: Study Language: en The final version of the questionnaire (in supplementary materials) featured 29 questions divided into three sections: the first focused on knowledge of asbestos risks and ARDs consisting of 14 questions; the second on awareness of asbestos risk and ARDs with 8 questions; and the third section on socio-demographic data of GPs, education level and patient caseload, which included 7 questions. Section title: Validated questionnaire Educational score: 1.513702630996704 Domain: biomedical Document type: Other Language: en In the knowledge section, the questionnaire contained 25 correct and 36 incorrect answer options. Section title: Validated questionnaire Educational score: 1.805745244026184 Domain: biomedical Document type: Study Language: en Each response was scored as follows: 1 point for a correct answer, 0 for no answer and −0.25 for an incorrect answer. Section title: Validated questionnaire Educational score: 2.868467330932617 Domain: biomedical Document type: Study Language: en To calculate the overall knowledge level, the formula previously developed was applied : [number of correct options + (−0.25*number of incorrect options)/25 correct options]*100. Based on the results, knowledge levels were categorized into four quartiles: scarce (0–24 %), sufficient (25–49 %), good (50–74 %) and optimal (75–100 %). Section title: Validated questionnaire Educational score: 2.577645778656006 Domain: biomedical Document type: Study Language: en For the awareness section, the total score was calculated by summing the responses to each questions. Furthermore, some questions (Q20, Q21 and Q22) were converted to a Likert scale, and the score was then expressed as a percentage to allow for comparison with the knowledge index. Awareness and competence scores were also divided into four quartiles: inadequate (0–24 %), poor (25–49 %), moderate (50–74 %), and high (75–100 %). Section title: Validated questionnaire Educational score: 1.8365367650985718 Domain: biomedical Document type: Study Language: en Missing responses (“no answer”) were considered as indicators of no knowledge or competence. Given the targeted group of respondents, hesitation in choosing an answer was interpreted as a potential knowledge gap regarding the specific topic. Section title: Validated questionnaire Educational score: 1.7146224975585938 Domain: biomedical Document type: Other Language: en To ensure strong participation, the research team attended EAT meetings, explaining the project's objectives and inviting GPs to participate after the read of the privacy data protection and informed consent. Section title: Statistical analysis Educational score: 3.8424394130706787 Domain: biomedical Document type: Study Language: en Data were analysed in aggregate form. Quantitative data were reported as medians and interquartile ranges (IQR) based on their distribution. Categorical variables were expressed as counts and percentages. To assess statistical significance, Mann-Whitney test was applied for comparisons between two groups while Kruskal-Wallis test was used for comparisons across multiple groups regarding quantitative data. For categorial data, associations were tested using Chi-square test, Fisher's exact test, or Cramer's V. The internal consistency of the Awareness section (Q15-Q19) was assessed using Cronbach's alpha. A two-sided p -value <0.05 was considered statistically significant. All statistical analyses were performed using IBM SPSS® version 25 for Windows. Section title: Study sample Educational score: 2.0712172985076904 Domain: biomedical Document type: Study Language: en GPs from non-operational EATs at the time of questionnaire distribution and who did not attend EAT meetings, were excluded from the investigation. Hence, 232 out of 280 GPs attended EAT meetings. Of these, only 216 (93,1 %) completed the questionnaire, and 56.5 % were male, with a median age of 60 years (IQR 42.25–64, supplementary table 1). Section title: Knowledge area Educational score: 4.067316055297852 Domain: biomedical Document type: Study Language: en Regarding the knowledge section (see Table 1 ), 59.3 % of GPs had a good level of knowledge and only 18 % an optimal level. The median knowledge score was 63 % (IQR 51–72). There was a statistically significant difference in knowledge levels among the seven districts ( p = 0.002), and difference became noticeable when comparing Casale Monferrato district to the others ( p < 0.001). GPs practicing in Casale Monferrato district exhibited a higher median knowledge level of 72 % (IQR 60–78), with 42.6 % achieving an optimal level of knowledge. Table 1 Descriptive statistics related to GPs' overall knowledge indexes in ASL AL districts emerged from the survey filled out during the EAT meetings . Table 1 TOTAL ASL AL DISTRICTS p ⁎ Casale Monferrato Other ASL AL Districts ASL AL p ⁎⁎ Alessandria Casale Monferrato Valenza Tortona Novi Ligure Ovada Acqui Terme ( n = 216) ( n = 64) ( n = 47) ( n = 17) (n = 21) ( n = 37) ( n = 11) ( n = 19) (n = 47) ( n = 169) N % N % N % N % N % N % N % N % N % N % Knowledge scarce 5 2.3 2 3.1 0 0.0 0 0 1 4.8 2 5.4 0 0 0 0 0.002 0 0.0 5 3.0 <0.001 sufficient 44 20.4 15 23.4 4 8.5 3 17.6 11 52.4 5 13.5 3 27.3 3 15.8 4 8.5 40 23.7 good 128 59.3 39 60.9 23 48.9 14 82.4 8 38.0 25 67.6 6 54.5 13 68.4 23 48.9 105 62.1 optimal 39 18.0 8 12.6 20 42.6 0 0 1 4.8 5 13.5 2 18.2 3 15.8 20 42.6 19 11.2 Median (IQR) 63 (51–72) 62 (49–71) 72 (60–78) 65 (56–70) 48 (39–63.5) 62 (52.5–69) 64 (47–71) 59 (51–71) 72 (60–78) 61 (49–70) ⁎ Kruskal-Wallis test. ⁎⁎ Mann-Whitney test. Section title: Knowledge area Educational score: 4.197136878967285 Domain: biomedical Document type: Study Language: en Regarding the evaluations for the knowledge-related questions, all items assessed showed a statistically significant association with the overall score level (see Table 2 ). However, a few items did not meet this criteria, including questions about personal protective equipment (Q4f), asbestos-related diseases (Q5b, Q5e), radiological signs of asbestosis (Q9, excluding answers related to pleural plaques), and anatomical structures where mesothelioma does not originate (Q13c). Knowledge evaluations for each ASL AL district are shown in supplementary table 2. Table 2 Knowledge of asbestos risk and ARDs, along with the association of overall scores to corresponding questions. Table 2 KNOWLEDGE TOTAL (n = 216) Association with knowledge score (p) ⁎⁎ Yes (knowledge) No (no knowledge) N % Overall Index No No answer Overall Index median score IQR N % N % median score IQR Q1) Asbestos is dangerous to human health 203 94.0 64.0 53–73 12 5.5 1 0.5 36.0 22.5–47 <0.001 Q2) Exposure to asbestos in living or working environments increases the risk of developing mesothelioma 200 92.6 64.0 54–73 16 7.4 – – 38.0 25–44 <0.001 Q3) The following types of asbestos exposure can influence the onset of malignant mesothelioma: a) Occupational exposure 182 84.3 64.5 55.75–73 31 14.3 3 1.4 43.0 30–55 <0.001 b) Family exposure 93 43.1 71.0 64–79 105 48.6 18 8.3 55.0 45–64 <0.001 c) Environmental exposure 147 68.1 66.0 59–74 62 28.7 7 3.2 51.0 39–64 <0.001 Q4) What types of personal protective equipment are effective in reducing the risk of occupational exposure to asbestos? a) Disposable coveralls 187 86.6 64.0 53–73 29 13.4 – – 55.0 36.5–63 0.001 b) Surgical masks 179 82.9 64.0 51–73 37 17.1 – – 58.0 46–67.5 0.040 c) Filtering face pieces 174 80.6 65.0 57–73.25 42 19.4 – – 47.0 33.75–55.5 <0.001 d) Washable rubber boots 95 44.0 70.0 59–76 121 56.0 – – 59.0 47–67 <0.001 e) Hearing protectors 187 86.6 62.0 49–72 29 13.4 – – 67.0 62–74 0.007 f) Heat resistant clothing 204 94.4 62.0 51–72 12 5.6 – – 69.5 60.5–72.75 0.182 Q5) Which of the following diseases are associated with asbestos exposure? a) Pulmonary asbestosis 207 95.8 64.0 52–72 9 4.2 – – 39.0 29.5–55.5 <0.001 b) Meningioma 209 96.8 63.0 51–72 7 3.2 – – 59.0 34–67 0.287 c) Pericardial mesothelioma 166 76.9 65.0 55.75–74 50 23.1 – – 49.5 36.25–62 <0.001 d) Mesothelioma of the tunica vaginalis testis 111 51.4 70.0 62–77 105 48.6 – – 54.0 44–64 <0.001 e) Non-Hodgkin lymphoma 194 89.8 63.0 51–72.25 22 10.2 – – 63.5 51.75–67.75 0.657 Q6) Which of the following are methods of exposure to asbestos? a) Domestic exposure, which refers to those living with someone who has been professionally exposed to asbestos 121 56.0 70.0 62–76.5 95 44.0 – – 51.0 40–62 <0.001 b) Environmental exposure, which refers to those who live in geographical areas contaminated by asbestos 189 87.5 64.0 54–73 27 12.5 – – 40.0 30–59 <0.001 c) Occupational exposure, which refers to those who carry out a professional activity in which asbestos is present 206 95.4 64.0 53–72.25 10 4.6 – – 37.5 22–45.25 <0.001 Q7) Based onthe literature, what is the primary symptom of asbestosis that is useful for directing the diagnosis? c. Exertional dyspnoea, which may progress to dyspnoea at rest 90 41.7 68.5 57.75–77.25 109 50.4 17 7.9 59.5 47–68 <0.001 Q8) When a worker is diagnosed with asbestosis, what does the GP need to report online? a. The physician submits a report online to INAIL 109 50.5 66.0 55.5–76.5 99 45.8 8 3.7 61.0 46–68 <0.001 Q9) What are the radiological signs of pulmonary asbestosis? a) Pleural plaques 99 45.8 61.0 47–69 117 54.2 – – 65.0 54.5–74 0.004 b) Fine basal reticular patterns 42 19.4 62.0 52.5–72 174 80.6 – – 63.5 51–72 0.727 c) A diffuse reticular-nodular pattern 137 63.4 64.0 51–73 79 36.6 – – 62.0 51–71 0.385 d) Air bronchograms 211 97.7 63.0 51–72 5 2.3 – – 57.0 22–64.5 0.159 e) Increased intercostal spaces 214 99.1 63.0 51–72 2 0.9 – – 47.5 n.c. ⁎ 0.165 Q10) From the literature, what is the average latency period for mesothelioma? e. Over twenty-five years 115 53.2 68.0 58–77 100 46.3 1 0.5 58.0 47–66 <0.001 Q11) Which of the following investigations is most suitable for the diagnosis and staging of pleural mesothelioma? b. Computed Tomography 165 76.4 65.0 55.5–73.5 45 20.8 6 2.8 51.0 40–63 <0.001 Q12) Which statement regarding pleural mesothelioma is correct? d. Asbestos exposure and tobacco smoking are synergistic risk factors 128 59.3 66.5 58.25–74.75 85 39.3 3 1.4 55.0 42.5–65 <0.001 Q13) From which of the following anatomical structures does mesothelioma NOT originate? a) Lymph nodes 99 45. 8 68.0 58–78 117 54.2 – – 59.0 45–66.5 <0.001 b) Meninges 112 51.9 65.0 55.25–75 104 48.1 – – 59.0 48.25–70.75 0.003 c) Pericardium 210 97.2 63.5 51–72 6 2.8 – – 57.0 41.25–61.25 0.152 d) Myocardium 85 39.4 66.0 55–78 131 60.6 – – 61.0 49–70 0.002 e) Vaginal tunic 183 84.7 65.0 54–73 33 15.3 – – 50.0 38.5–58.5 <0.001 Q14) According to Law 257/92 which regulations relateto the cessation of asbestos use? Asbestos exposure is permitted, with appropriate safety measures for workers, in the following activities d. Disposal and/or remediation of areas or artefacts containing asbestos 167 77.3 65.0 55–74 41 19.0 8 3.7 50.0 38.5–64 <0.001 ⁎ Not calculable because of the low number of responses in the group. ⁎⁎ Mann-Whitney test. Section title: Knowledge area Educational score: 3.7379486560821533 Domain: biomedical Document type: Study Language: en Although there was a high and widespread knowledge about the health hazards of asbestos (94 %) ( Table 2 , Q1) and the increased risk of mesothelioma due to this exposure (92.6 %, Q2), significant disparities were evident both in the variation of knowledge among different districts and when comparing Casale Monferrato district with the others. The greatest variations in knowledge were particularly noted in the following areas: types of asbestos exposure, procedures for reporting occupational diseases, and understanding of mesothelioma, including latency, diagnostic methods, and risk factors. Section title: Knowledge area Educational score: 3.842212438583374 Domain: biomedical Document type: Study Language: en Regarding the types of asbestos exposure linked to mesothelioma (Q3), the rates were 84.3 % for occupational exposure 84.3 %, and 68.1 % and 43.1 % for environmental and domestic exposure, respectively. Domestic exposure had the highest rate of missing responses (8.3 %) and knowledge for this type of exposure (Q3b) showed significant differences among the districts ( p = 0.039), with Casale Monferrato reporting the highest awareness (53.2 %). Statistically significant differences were also observed when comparing Casale Monferrato to the other districts ( p = 0.008). Section title: Knowledge area Educational score: 3.3562333583831787 Domain: biomedical Document type: Study Language: en Furthermore, when evaluating types of asbestos exposure (Q6), the one least identified by GPs was domestic exposure (Q6a); only 56 % of them recognising it as a mode of exposure, compared to environmental (87.5 %) and occupational exposure (95.4 %). Statistically significant differences in knowledge were found both among the different districts ( p = 0.003) and between Casale Monferrato and the other districts ( p = 0.001). Section title: Knowledge area Educational score: 2.1220052242279053 Domain: biomedical Document type: Study Language: en Regarding the symptomatology for asbestosis, only 41.7 % of GPs correctly identified dyspnoea on exertion followed by dyspnoea at rest (Q7). Casale Monferrato had the highest correct response rate (51.1 %). However, there were no statistically significant differences in knowledge among the districts or in comparison to Casale Monferrato. Section title: Knowledge area Educational score: 2.594428539276123 Domain: biomedical Document type: Study Language: en Regarding the reporting of asbestosis diagnoses for workers exposed to asbestos, only half of the GPs correctly reported the procedure for notifying the National Institute for Insurance against Accidents at Work (INAIL) via electronic platform (Q8). Analysis of the correct and incorrect responses revealed a statistically significant difference between the districts as well as when comparing each district with Casale Monferrato ( p < 0.001). GPs practising in Casale Monferrato demonstrated better knowledge of the reporting procedure, with 78.7 % answering correctly. Section title: Knowledge area Educational score: 2.4950406551361084 Domain: biomedical Document type: Study Language: en In contrast, on the other hand, when asked about the average latency period for the development of mesothelioma, 46.8 % of GPs failed to provide the correct, which is over 25 years (Q10). There was a statistically significant difference in responses among the districts (p < 0.001), and also when comparing the responses from Casale Monferrato with those from all other districts ( p = 0.001). Section title: Knowledge area Educational score: 2.8049397468566895 Domain: biomedical Document type: Study Language: en Additionally, the identification of the correct investigation for the diagnosis and staging of pleural mesothelioma (Q11) showed differing levels of knowledge among the districts ( p = 0.047), as well as in comparison with Casale Monferrato ( p = 0.048). Section title: Knowledge area Educational score: 3.520188570022583 Domain: biomedical Document type: Study Language: en Finally, statistically significant differences were found among the districts in correctly identifying the relationship between asbestos exposure and mesothelioma (Q12), specifically that exposure to asbestos and tobacco smoke act as combined risk factors ( p = 0.004). Section title: Awareness area Educational score: 4.0165557861328125 Domain: biomedical Document type: Study Language: en The analysis of awareness index ( Table 3 ) revealed a moderate/high overall level of 62 % (median: 54 %, IQR: 46–62). Only 4.6 % of GPs reported a high level of awareness. There were no statistically significant differences in awareness levels when comparing the seven districts or between Casale Monferrato and the other districts ( p > 0.05). Table 3 Descriptive statistics related to GPs' overall awareness indexes in ASL AL districts emerged from the survey filled out during the EAT meetings . Table 3 TOTAL ASL AL DISTRICTS p ⁎ Casale Monferrato Other ASL AL Districts p ⁎⁎ Alessandria Casale Monferrato Valenza Tortona Novi Ligure Ovada Acqui Terme (n = 216) (n = 64) (n = 47) (n = 17) (n = 21) (n = 37) (n = 11) (n = 19) (n = 47) (n = 169) N % N % N % N % N % N % N % N % N % N % Awareness 0.065 0.060 inadequate 3 1.4 1 1.6 0 0.0 0 0.0 0 0.0 1 2.7 0 0.0 1 5.3 0 0.0 3 1.8 poor 79 36.6 30 46.9 14 29.8 4 23.5 5 23.8 14 37.8 4 36.4 8 42.1 14 29.8 65 38.5 moderate 124 57.4 30 46.9 29 61.7 12 70.6 15 71.4 22 59.5 6 54.5 10 52.6 29 61.7 95 56.2 high 10 4.6 3 4.6 4 8.5 1 5.9 1 4.8 0 0.0 1 9.1 0 0.0 4 8.5 6 3.5 Median (IQR) 54 (46–62) 51 (43–59.5) 57 (49–65) 57 (50–64) 62 (50–68) 52 (45.5–60.5) 57 (48–69) 52 (45–60) 57 (49–65) 52 (45.5–62) ⁎ Kruskal-Wallis test. ⁎⁎ Mann-Whitney test. Section title: Awareness area Educational score: 2.294428586959839 Domain: biomedical Document type: Study Language: en The reliability of the scale for questions Q15 to Q19 (12 items) was more than acceptable, with a Cronbach's alpha of 0.73. Section title: Awareness area Educational score: 4.181758403778076 Domain: biomedical Document type: Study Language: en Regarding the awareness items ( Table 4 ), all associations between the overall score and the individual areas were statistically significant. Awareness evaluations for each ASL AL district are reported in supplementary table 3. Table 4 Awareness/competence on asbestos risk and ARDs and association of overall score with the corresponding questions. Table 4 AWARENESS TOTAL (n = 216) Association with awareness score (p) ⁎ Yes (aware) No (not aware) Overall Index No No answer Overall Index N % median score IQR N % N % median score IQR Q15) Which of the following actions related to occupational diseases fall within your scope of responsibility? a) Diagnosis 175 81.0 57.0 48–63 35 16.2 6 2.8 43.0 34.5–52 <0.001 b) Complaint/ formal notification 140 64.8 57.0 49–65 66 30.6 10 4.6 49.0 40.50–57 <0.001 c) Compilation of medical certificates 142 65.7 57.0 49–65 57 26.4 17 7.9 48.5 41.5–57 <0.001 What factors contribute to the difficulty in reporting an occupational disease? a) Inexperience with bureaucratic procedures 17 7.9 72.0 62.5–80.5 184 85.2 15 6.9 52.0 46–60 <0.001 b) Challenges in carrying out bureaucratic procedures 12 5.6 71.0 62.25–77.75 191 88.4 13 6.0 52.0 46–60 <0.001 c) Lack of understanding of diagnostic criteria 76 35.2 62.5 57–71 117 54.2 23 10.6 49.0 43–57 <0.001 d) Lack of time 86 39.8 60.0 52–68.25 105 48.6 25 11.6 50.0 43–58 <0.001 e) Inadequate professional updating (ECM, etc.) 53 24.5 63.0 57.5–72 147 68.1 16 7.4 51.0 43–58 <0.001 f) Complexity of the List of occupational diseases for which reporting is mandatory 29 13.4 68.0 61–73 170 78.7 17 7.9 52.0 45–58 <0.001 Q17) Do you feel that your current level of scientific and professional knowledge on asbestos-related diseases is sufficient to address patient inquiries regarding occupational diseases and workplace accidents?” 55 25.5 58.0 49–71 160 74.0 1 0.5 52.0 46–60 <0.001 Q18) Do you find the Continuing Medical Education (CME) in the Piedmont Region to be adequate in covering asbestos-related diseases? 38 17.6 59.0 48.75–72 177 81.9 1 0.5 52.0 46–62 0.004 Q19) Are you well-informed about the occupational activities of your patients? 136 63.0 57.0 49–65 79 36.5 1 0.5 49.0 42–57.75 <0.001 Q20) In the last 12 months, have you followed Continuing Medical Education courses (ECM) that covered or included topics on asbestos-related diseases? 12 5.6 61.5 57–73.25 203 93.9 1 0.5 52.0 46–62 0.010 Q21) In the past 12 months, have you seen or treated patients with asbestos-related conditions? 65 30.1 58.0 49–68 151 69.9 – – 52. 0 45–60 0.001 Q22) In the last 5 years, how many occupational disease reports related to asbestos exposure have you submitted? 53 24.5 57.0 51–70 161 74.6 2 0.9 52.0 45–60 0.002 ⁎ Mann-Whitney test. Section title: Awareness area Educational score: 2.541537284851074 Domain: biomedical Document type: Study Language: en Regarding GPs' awareness, statistically significant differences were found among the districts for the following issues: competence in occupational diseases, especially on the diagnosis and lack of knowledge of the diagnostic criteria for recognising ARDs; complexity of the list of occupational diseases; inadequate and unsatisfactory level of scientific and professional training on ARDs; examining patients with ARDs and the compilation of occupational disease reports. Section title: Awareness area Educational score: 2.042008638381958 Domain: biomedical Document type: Study Language: en About GPs' competence in diagnosing occupational diseases (Q15a), no significant differences were observed between districts, except for a difference with Casale Monferrato ( p = 0.042). Section title: Awareness area Educational score: 3.5906789302825928 Domain: biomedical Document type: Study Language: en In terms of barriers for reporting occupational diseases, statistically significant differences were found for the lack of knowledge of diagnostic criteria (Q16c), both among districts ( p < 0.001) and compared to Casale Monferrato ( p = 0.001). Differences were also observed for lack of time (Q16d) and the complexity of the occupational diseases (Q16f) among districts ( p = 0.036 and p = 0.049 respectively), but not when compared to Casale Monferrato. Conversely, this difference was evident for the item on inadequate professional updating, but not among districts (p = 0.036). Section title: Awareness area Educational score: 2.7511322498321533 Domain: biomedical Document type: Study Language: en A key finding from the analysis is that many GPs (74 % with a score ≤ 3) did not feel that their current level of scientific and professional training on ARDs is sufficient to answer patients' questions on occupational diseases and workplace accidents (Q17). This was statistically significant both among districts and compared to Casale Monferrato ( p ≤0.001). Only 8.5 % of GPs in Casale Monferrato rated their training as inadequate, compared to higher rates in other districts. Section title: Awareness area Educational score: 2.1300532817840576 Domain: biomedical Document type: Study Language: en Furthermore, 81.9 % of GPs considered as inadequate the quality of Continuing Medical Education (CME) on asbestos and ARDs (Q18) and only 5.6 % reported attending CME courses in the past 12 months that included topics on ARDs (Q20). Section title: Awareness area Educational score: 3.0684330463409424 Domain: biomedical Document type: Study Language: en Additionally, 69.9 % of GPs (1.4 % who failed to recall) reported they had not evaluated ARD cases in the previous year (Q21). Significant differences were observed between districts and in comparison with Casale Monferrato. Notably, 78.7 % of GPs in Casale Monferrato, reported their experience in visiting patients with ARD ( p < 0.001). The median number of patients visited was 2.50 (IQR 2–6.25) in Casale Monferrato, compared to 1 (IQR 1–2) in the other districts (p < 0.001). Section title: Awareness area Educational score: 2.326566457748413 Domain: biomedical Document type: Study Language: en Approximately 75 % of GPs had no experience in filling occupational disease reports in the last 5 years (Q22), while 5.1 % had submitted at least five. Conversely, 38.3 % of GPs in Casale Monferrato district submitted reports during the period (14.9 % of whom had completed at least five certificates), compared to 20.7 % in the other districts ( p = 0.005). Section title: Awareness area Educational score: 2.204577684402466 Domain: biomedical Document type: Study Language: en Finally, from the analysis of demographic and workload data of GPs (supplementary table 4) an increase in knowledge was observed in younger GPs (p < 0.001) and thus lower seniority ( p = 0.006). Section title: Awareness area Educational score: 2.9257752895355225 Domain: biomedical Document type: Study Language: en GPs with a General Medicine qualification demonstrated a higher overall knowledge index, compared to those with a specialization ( p = 0.001). Furthermore, the overall knowledge index was higher in GPs who had visited and treated patients with ARDs in the past year, compared to those who had not (p < 0.001). Section title: Awareness area Educational score: 2.2244632244110107 Domain: biomedical Document type: Study Language: en Concerning workload activity, knowledge was higher in those with a higher patients' daily contact ( p = 0.029) and daily outpatient hour ( p = 0.037). Section title: Discussion Educational score: 2.5552940368652344 Domain: biomedical Document type: Study Language: en GPs play a crucial role in the early diagnosis and correct management of patients with ARDs. For this reason, this project aimed to explore the levels of knowledge, awareness and experience of ARDs among those GPs practising in ASL AL. The assessment focused on clinical features, prevention, patient communication, legal and administrative procedures, also assessing differences between Casale Monferrato district, with its history of asbestos exposure and serious health consequences on citizens' health, and the others. Section title: Discussion Educational score: 2.1110193729400635 Domain: biomedical Document type: Study Language: en This is the first project to comprehensively evaluate the level of knowledge and competence regarding asbestos risk, as well as the experience of GPs in diagnosing and managing ARDs in ASL AL. This initiative is the second of its kind in Italy, following a pilot project organized by the University of Molise in 2021 in its regional territory. Section title: Discussion Educational score: 1.4237884283065796 Domain: other Document type: Other Language: en ASL AL covers an extensive area, but the asbestos issue is particularly focused in Casale Monferrato. The characteristics of this district, recognised as a NPCS, contribute to the higher level of knowledge observed among GPs working there. As a national role model in the fight against asbestos, GPs in Casale Monferrato possess greater awareness and understanding of this issue. Section title: Discussion Educational score: 1.9672316312789917 Domain: biomedical Document type: Study Language: en The analysis of knowledge and awareness/competence indexes highlights critical areas requiring attention, particularly the factors that most impacted overall scores. Section title: Discussion Educational score: 1.9220227003097534 Domain: biomedical Document type: Other Language: en The level of knowledge was very high on the danger of asbestos for health and the increased risk of developing mesothelioma that it causes, as well as on the role of occupational exposure in their occurrence, while the determinant of mesothelioma due to exposure in the family home setting was the less recognised. Section title: Discussion Educational score: 1.9902446269989014 Domain: biomedical Document type: Other Language: en Based on the differences in knowledge observed among GPs in Casale Monferrato with respect to all the other ASL AL districts, the analysis reveal the need for more in-depth knowledge on ARDs, even in view of the unknown asbestos exposures emerging with the new mesothelioma cases and those still occurring even outside the NPCS of Casale Monferrato. Section title: Discussion Educational score: 2.250495672225952 Domain: biomedical Document type: Other Language: en These results suggest that GPs' education on environmental pollutant-related disease should be implemented not only in NPCSs and should start since the university, including scientific knowledge, differential diagnostics and medical-legal aspects. Section title: Discussion Educational score: 1.5883758068084717 Domain: biomedical Document type: Other Language: en However, the asbestos issue is not limited to Italy, but it represents a global concern. Although banned in many countries, there are still several realities in which asbestos is still used, and others in which only recently has been banned , with an increasing amount of diagnosis of illness related to asbestos exposure . Section title: Discussion Educational score: 1.9422498941421509 Domain: biomedical Document type: Other Language: en Indeed, there are globally developed research data which have claimed that asbestos, besides contributing to several types of cancer, thus representing a serious public health risk, is a problem especially in developing countries and in those where asbestos use bans and coordinated management plans have not been implemented . Section title: Discussion Educational score: 2.901616334915161 Domain: biomedical Document type: Study Language: en Moreover, the Global Cancer Observatory, Cancer Incidence in Five Continents Plus, and Global Burden of Disease were recently consulted for mesothelioma incidence and its risk factors worldwide. Although a substantial decrease in mesothelioma trends has been observed, especially in highly developed countries, probably attributable to the complete ban several years ago on asbestos use, stable and increasing trends have been observed in several countries . Section title: Discussion Educational score: 2.3238284587860107 Domain: biomedical Document type: Other Language: en In this context Casale Monferrato represents a model in the fight against asbestos, especially due to the epidemiological studies conducted since 1980s , hence this experience can also support countries where this problem is emerging. In these realities, information should be provided on the knowledge of risk related to asbestos exposure, as well as on the disease features (such as latency and clinical signs for correct differential diagnosis) to promptly start the medical-legal recognition process, where it exists, through an efficient educational program to healthcare professionals and physicians. Section title: Discussion Educational score: 1.9197784662246704 Domain: biomedical Document type: Other Language: en Furthermore, it is imperative to mention the heterogeneity of NPCSs. Beyond the well-known asbestos pollution, many other NPCSs in Italy are responsible for the development of several diseases. The most notable pollutants include chemical plants, coal mines, petrochemical plants and refineries, steel industries, harbors areas, landfills of hazardous or mixed waste, electric power plants and first-generation incinerators . Section title: Discussion Educational score: 1.5921974182128906 Domain: biomedical Document type: Other Language: en Because of the heterogeneity in the contamination of NPCSs, this survey could be adapted to other territorial areas with different environmental contamination, as well as in neighboring areas. The questionnaire used could be a valuable research tool for homogeneous data collection among different NPCSs, useful for describing potential requirements. Section title: Conclusions Educational score: 2.208392381668091 Domain: biomedical Document type: Other Language: en This survey highlights the need to provide for GPs topic-specific update courses that would enable them to increase knowledge on recognising ARDs symptoms, and to guide the patient towards early diagnosis, likewise in the occupational disease notification process. It would be useful to extend this assessment to all areas with a history of previous asbestos exposure, including NPCSs and those areas that despite showing this issue do ot have such recognition. Section title: Conclusions Educational score: 1.6650135517120361 Domain: biomedical Document type: Other Language: en Furthermore, the developed questionnaire could be a useful tool for decision makers for defining and planning strategic actions on asbestos. For the same purpose, it could be adapted to different realities also with a history of environmental pollutants exposure different from asbestos. Section title: Funding Educational score: 1.0218957662582397 Domain: other Document type: Other Language: en This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Section title: CRediT authorship contribution statement Educational score: 0.9628406763076782 Domain: other Document type: Other Language: en Marinella Bertolotti: Writing – review & editing, Writing – original draft, Supervision, Project administration, Methodology, Investigation, Data curation, Conceptualization. Manuela Tamburro: Writing – review & editing, Methodology. Angelo Salzo: Writing – review & editing, Methodology. Antonella Cassinari: Writing – review & editing, Writing – original draft, Project administration, Methodology, Data curation. Stefania Crivellari: Writing – review & editing, Writing – original draft, Project administration, Investigation. Carlotta Bertolina: Writing – review & editing, Writing – original draft, Project administration, Investigation. Marianna Farotto: Writing – review & editing, Project administration, Investigation. Carmen Adesso: Writing – review & editing, Methodology. Michela Anna Di Palma: Writing – review & editing, Methodology. Anna Natale: Writing – review & editing, Methodology. Federico Torregiani: Writing – review & editing, Project administration, Conceptualization. Guglielmo Pacileo: Writing – review & editing, Project administration, Conceptualization. Antonio Maconi: Writing – review & editing, Supervision, Conceptualization. Giancarlo Ripabelli: Writing – review & editing, Methodology. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Review | biomedical | en | 0.999997 |
PMC11697735 | Section title: Introduction Educational score: 1.9298192262649536 Domain: biomedical Document type: Other Language: en Artificial intelligence (AI) has gotten much attention in recent years and has developed into an essential component in both modern medicine and society. Artificial intelligence has sifted from being an absolute statistical instrument to being a key driver of modern medicine . Section title: Introduction Educational score: 1.3516703844070435 Domain: other Document type: Other Language: en The expression "Artificial Intelligence" was first used in 1956 at a conference, although the theory behind it dates back to 1943. The objective was to develop computers that could perform activities that humans could perform . Section title: Introduction Educational score: 2.2313590049743652 Domain: biomedical Document type: Other Language: en Using algorithms included in decision support systems, artificial intelligence and its subsets, machine learning, and deep learning, have been extended to analyze complex data collected from multiple sources and have been applied to a variety of dental procedures . Section title: Introduction Educational score: 1.8002785444259644 Domain: biomedical Document type: Other Language: en AI applications in dentistry were first studied in 1992 . While improvements in AI may not seem to have much of an impact on dentistry overall, several fields have greatly benefited from them, like image-based automatic disease identification and other specialized diagnostic systems, as well as the resolution enhancement of images connected to dentistry . Section title: Introduction Educational score: 2.196744203567505 Domain: biomedical Document type: Other Language: en AI has been used in dentistry not only to anticipate and prevent dental problems but also to provide value-based care. AI plays a crucial role in dentistry because it has an enormous ability to find and diagnose oral lesions that are not visible to the human eye. Developments in artificial intelligence may lessen the frequency of avoidable surgical procedures in the medical field, enhance quality of life, relieve postoperative problems, and enhance decision-making . Section title: Introduction Educational score: 2.00593638420105 Domain: biomedical Document type: Other Language: en The frequency with which AI applications are being employed in clinical care, research, and education is reflected in the current surge in interest in training AI to medical students. Numerous associations have proposed that AI, data sourcing and safety, ethics, and the critical assessment and interpretation of AI applications in healthcare be taught to healthcare workers . Section title: Introduction Educational score: 1.695595622062683 Domain: biomedical Document type: Other Language: en Concerning this continuing AI revolution, it is fundamental to make sure that existing and future clinical workers are up to date regarding the ability of this new technology . Section title: Introduction Educational score: 1.6797646284103394 Domain: biomedical Document type: Other Language: en It is becoming more apparent that dental students have to learn about AI technologies. Consequently, it would be required to conduct a survey among dental undergraduate students in order to assess their opinions and thoughts about how AI might affect the area of dentistry . Section title: Introduction Educational score: 1.664716124534607 Domain: biomedical Document type: Other Language: en A number of studies have been done to evaluate dentistry students' knowledge of artificial intelligence (AI), including ones in Brazil , India , Morocco , Peru , Saudi Arabia , and South Korea Turkey and United Arab Emirates . Section title: Introduction Educational score: 3.8537726402282715 Domain: biomedical Document type: Review Language: en Amiri et al., conducted a systematic review and meta-analysis that provided data regarding the attitudes, knowledge, and skills of medical, dental, and nursing students concerning artificial intelligence, evaluating 5789 participants from 24 studies. Overall, 44% of students showed a medium to high level of knowledge of AI applications and principles. Most students, however, knew very little about artificial intelligence. Although students demonstrated moderate knowledge, they generally had positive attitudes towards AI, as 65% of all students agreed with the use of AI in medicine and had a favorable view. Section title: Introduction Educational score: 2.153571844100952 Domain: biomedical Document type: Study Language: en To the best of the authors’ knowledge, no research has been done about Egyptian dental students’ thoughts and attitudes regarding the employment of AI in the dental field. Therefore, this study aimed to evaluate Egyptian dental students' knowledge, attitudes, and perceptions toward AI. Section title: Study design Educational score: 2.352118730545044 Domain: biomedical Document type: Study Language: en The present study is a cross-sectional questionnaire study conducted among a group of dental students in Egypt. Using Google Forms, an electronic link to the questionnaire was created and dispersed via email to the participants. The reporting of this observational study was ensured by applying the STROBE principles. Section title: Ethical aspects Educational score: 1.4946807622909546 Domain: biomedical Document type: Other Language: en The Helsinki Declaration was followed in the conduct of the current study. The Cairo University Faculty of Dentistry's Ethics Committee of Scientific Research granted ethical permission on 28/11/2023, with approval number (321,123). Students were informed about the purpose of the study and informed consent was requested at the start of participation to answer the online survey questionnaire while maintaining their anonymity and confidentiality according to the survey's settings. Section title: Sample size Educational score: 2.2710578441619873 Domain: biomedical Document type: Study Language: en Based on the findings of where dental students responded with a frequency of (48.4%) to the knowledge about AI, the expected sample size (n) was a total of (384) cases by implementing a (95%) confidence interval. Epi info application was employed for sample size calculation. Section title: Inclusion criteria Educational score: 1.7188478708267212 Domain: biomedical Document type: Other Language: nl Undergraduate dental students Egyptian dental students Both genders were included Section title: Exclusion criteria Educational score: 1.4294739961624146 Domain: other Document type: Other Language: en Students reluctant to participate and refusing to complete the informed consent. Students with skipping records, who didn’t respond to all the survey questions. 1st and 2nd-year students. Graduates students Section title: Outcomes Educational score: 2.160135507583618 Domain: biomedical Document type: Study Language: en This survey aimed to assess Egyptian dental students' knowledge, attitudes, and perceptions towards AI. Section title: Data sources and measurement Educational score: 2.2122139930725098 Domain: biomedical Document type: Study Language: en The data collection tool was a pre-prepared- validated English questionnaire based on Yüzbaşıoğlu, 2020 previous work that was pretested on a group of dental students and showed internal consistency of the survey using the Cronbach’s (= 0.83). Yüzbaşıoğlu, 2020 questionnaire was used without modification. Section title: Data sources and measurement Educational score: 1.8415285348892212 Domain: biomedical Document type: Study Language: en The electronic survey constructed using Google Forms was distributed to dental students fulfilling the eligibility criteria. Two universities were included in this study: the Faculty of Dentistry, Cairo University, and the Egyptian Russian University. Section title: Data sources and measurement Educational score: 1.723981261253357 Domain: biomedical Document type: Study Language: en A consent section explaining the study's purpose, survey nature, and voluntary contribution prefaced the questionnaire. Before proceeding with responding to the questionnaire. Informed consent was taken from each participant by answering a (Yes/No) question. Section title: Data sources and measurement Educational score: 2.0455162525177 Domain: biomedical Document type: Study Language: en The questionnaire comprised 3 sections and 22 questions. The initial part of the survey gathered data (4 questions) on sociodemographic characteristics such as age, gender, attending University, and dental education. In the subsequent part, the participants were inquired 3 questions about having a basic knowledge of AI working principles, awareness of AI usage in dentistry, and the information source of AI applications. In the third section, the participants were asked to identify their agreement level to 15 statements. Section title: Bias Educational score: 2.0691301822662354 Domain: biomedical Document type: Study Language: en To reduce selection bias, all dental students at participating dental schools were encouraged to anonymously complete the survey. To reduce information bias, the nature of the study and its objective were explained to each participant in the same way. Section title: Statistical analysis Educational score: 3.6857988834381104 Domain: biomedical Document type: Study Language: en Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS) version 22.0 statistical analysis tool. Data normality was tested using the Kolmogorov–Smirnov test. The normally distributed data were compared using the independent samples t-test and one-way analysis of variance. The chi-square test was used to assess the categorical data. The analysis's results were shown as frequency (percent) for categorical data. For quantitative data, the analysis's results were shown as mean ± standard deviation. A significance level of P < 0.05 was chosen. Section title: Results Educational score: 2.165297269821167 Domain: biomedical Document type: Study Language: en A total of 384 dental students took part in this survey, 241(63%) students from Cairo University and 143 (37%) students from Egyptian Russian University. The mean age of dental students was 19 ± 1.5 years old. Of the participants, 160 (42%) were male and 224 (58%) were female. 83 (21%) of the participants were third-year, 99 (26%) were fourth-year ( n = 134), and 202 (53%) were fifth-year dental students. The first and second-year students were not invited to fill out the questionnaire. Section title: Results Educational score: 1.982815146446228 Domain: biomedical Document type: Study Language: en Regarding the basic knowledge questions of the working principles of AI, 187 (49%) of the participants were knowledgeable about AI, while 197 (51%) were not (yes vs. no answer). 186 (48%) students were aware of AI usage in dentistry, whereas 198 (52%) were not (yes vs. no answer). Social media was the most common information source of AI applications ( n = 290,76%) followed by “Friends, family” and “Lectures in university” ( n = 37,9% and n = 39,10% respectively), and “Newspaper, magazines” was the least common source ( n = 18,5%). Section title: Results Educational score: 3.4763245582580566 Domain: biomedical Document type: Study Language: en There was an insignificant statistical difference between knowledge about AI and gender, type of attending university, and the education year with p values (0.924, 0.442, and 0.105), respectively. Also, an insignificant statistical difference was observed between awareness of AI usage in dentistry and gender, type of attending university, and the education year with p values (0.978, 0.459, and 0.701), respectively. Table 1 . Table 1 Responses to the questionnaire's second section in relation to demographic data Variable knowledge about AI Awareness of AI usage in dentistry Number (N) Percentage (%) Yes No Chi-square Yes No Chi-square Gender Male 160 42% 76 84 0.924 81 79 0.978 Female 224 58% 111 113 111 113 Attending University Cairo university 241 63% 121 120 0.442 124 117 0.459 Egyptian Russian university 143 37% 66 77 68 75 Dental education year 3rd year 83 21% 45 38 0.105 44 39 0.701 4th year 99 26% 54 45 51 48 5th year 202 53% 88 114 97 105 Section title: Results Educational score: 1.7279455661773682 Domain: biomedical Document type: Other Language: en Moreover, most of the participants agreed on the leading role of AI in the advancement of dentistry and disagreed on the ability of AI to replace dentists in the future, (53%) and (44%) respectively. Section title: Results Educational score: 2.1173081398010254 Domain: biomedical Document type: Study Language: en When asked about the role of AI in the diagnosis and prediction of oral diseases, most students found the use of AI diagnosis exciting and agreed with its definitive role in disease prediction (57% and 33%, respectively). Section title: Results Educational score: 3.3862717151641846 Domain: biomedical Document type: Study Language: en It was extensively agreed that AI could be used for the diagnosis of dental caries, periodontal diseases, soft tissue lesions, and pathologies in the jaws radiographically (58%, 56%, 49%, and 51% agreement respectively) in contrast to (10%, 9%, 19% and 15% disagreement respectively). Section title: Results Educational score: 2.052354574203491 Domain: biomedical Document type: Study Language: en Regarding the importance of AI in implantology, (54%) of students found AI useful, opposite to (3%) of the participants. In addition, the majority of participants (58%) think that AI could be useful in diagnosis and treatment planning in dentistry, and only (1%) disagreed. Section title: Results Educational score: 1.9382370710372925 Domain: biomedical Document type: Study Language: en Whereas a large number of participants (40%) had no idea about the role of AI in forensic dentistry, (44%) agreed on its usefulness in forensic dentistry, and the majority (62%) found AI useful as a “quality control tool” and in the assessment of treatments success. Section title: Results Educational score: 1.9506820440292358 Domain: biomedical Document type: Study Language: en Finally, (49%) and (52%) respectively of the participants approved the incorporation of AI applications in undergraduate and postgraduate dental training. Section title: Results Educational score: 1.5113314390182495 Domain: biomedical Document type: Other Language: en Responses to the questionnaire's third section are shown in Fig. 1 . Fig. 1 Responses of the questionnaire's third section Section title: Discussion Educational score: 1.8404589891433716 Domain: biomedical Document type: Other Language: en The usage of AI in dentistry is a fast-developing area. Artificial intelligence (AI) applications in practice have challenged the clinical and educational features of dentistry. Nevertheless, AI will unavoidably have a big influence on dental education in the future. The AI paradigm shift makes it clear that universities' dental curricula need to be modified . Section title: Discussion Educational score: 1.7668944597244263 Domain: biomedical Document type: Other Language: en A survey to ascertain the opinions and attitudes of dentists across all generations is necessary in order to guarantee the proper development and application of dental AI . Section title: Discussion Educational score: 2.003469467163086 Domain: biomedical Document type: Study Language: en Several studies in different countries, such as Brazil , Turkey , Saudi Arabia , India , Morocco , and South Korea have been conducted to assess dental students' knowledge about AI. However, there has been no such attempt in Egypt, and to the authors' knowledge, this is the first survey conducted in Egypt among dental students to collect their knowledge and perceptions of AI. Section title: Discussion Educational score: 2.2762844562530518 Domain: biomedical Document type: Study Language: en The male-to-female ratio in the current survey was (42% male compared to 58% female). Similarly, more female participation was reported by Yüzbaşıoğlu, 2020 (59% females and 41% males), Murali et al., 2023 (73% female and 27% male), and Elhijazi and Benyahya, 2023 (71.4% female and 28.9% male). Yet, Khanagar et al., 2021 reported an equal number of participants from both genders (49.2% females and 50.8% males). Section title: Discussion Educational score: 2.949012517929077 Domain: biomedical Document type: Study Language: en In this work, the majority of students were fifth-year dental students (53%), followed by the fourth-year (26%) and third-year (21%). In Yüzbaşıoğlu, 2020 study, second-grade dental students had the majority of participation (36.90%), and fifth-grade dental students had the least participation (8.80%). In Murali et al., 2023 study, the majority of participants (20.7%) were postgraduate students, and the least were third-year students and interns(19.3%). Khanagar et al., 2021 reported that sixth-year dental students and first-year dental students were the most and least to participate in his study (26.7% and 6.9%), respectively. Section title: Discussion Educational score: 2.0480380058288574 Domain: biomedical Document type: Other Language: en As recommended by the WHO, health professionals must understand the basic functioning of artificial intelligence to make full and appropriate use of its broad. . In terms of participants' basic understanding of AI's operating principle, (49%) of the participants were knowledgeable about AI, (48%) students were aware of its usage in dentistry. Section title: Discussion Educational score: 2.946176528930664 Domain: biomedical Document type: Study Language: en Close responses were shown by Yüzbaşıoğlu, 2020 as most students were aware of AI; however, the knowledge about its principles was low (48.40%%) and also by Elhijazi and Benyahya, 2023 , where 43.6% of students did not know the basic principle of AI. Similarly, a split decision was detected in Khanagar et al., 2021 study (50.1%) with only a one-participant difference. However, higher knowledge levels were reported by Murali et al., 2023 (94.13%) were acquainted with the term artificial intelligence, whereas 73.70% were aware of its basic working concept) and by Kalaimani et al., 2023 (63.5% knew AI and 380 (38%) were aware of its apps. This difference in findings could be attributed to that some dental schools have initiated presenting AI-related programs. Section title: Discussion Educational score: 1.431985855102539 Domain: other Document type: Study Language: en In most of the studies, the participants have learned about AI in social media [Yüzbaşıoğlu, 2020 (76.1%), Khanagar et al., 2021 (40.9%), Aldowah et al., 2024 (78%)]. This could be explained because the majority of people in today's world use social media and almost all have smartphones. Additionally, posts about AI concepts and applications are common on social media . Similarly, in this study, social media was the most prevalent source of AI applications (76%), and “Newspaper, magazines” were the least common source (5%). Section title: Discussion Educational score: 2.0098636150360107 Domain: biomedical Document type: Study Language: en When asked if AI will alter the future of dentistry, over half of the participants (53%) agreed on the leading role of AI in the advancement of dentistry. This positive opinion on the utility of dental AI was reported by [Yüzbaşıoğlu, 2020 (85.70%), Khanagar et al., 2021 (72.17%) and Jeong et al., 2024 (64.2%),]. Section title: Discussion Educational score: 1.4201635122299194 Domain: other Document type: Other Language: en It was reported that one of the most significant industries to use AI is dentistry; nevertheless, understanding of AI is not keeping up with the low usage of AI applications in this field. As a result, some dentists worry that AI could pose a threat to them in the future . Section title: Discussion Educational score: 2.951535940170288 Domain: biomedical Document type: Study Language: en In this context, (44%) of students in the current study disagreed on the ability of AI to replace dentists in the future. Similarly, most students in Jeong et al., 2024 did not believe it would replace (71.9%), and half of the participants in Yüzbaşıoğlu, 2020 did not agree that AI could replace themselves soon. However, over half of the students (53.7%) in Elhijazi and Benyahya, 2023 study believed that AI will replace humans in dentistry and expressed moderate to significant concerns about AI. According to Yüzbaşıoğlu, 2020 , there are certain difficulties, such as the fact that AI is unable to engage in in-depth conversations with patients in order to win their trust, reassure them, and show empathy. Physicians will still be needed to integrate medical histories, conduct physical examinations, and promote additional discussion in unclear cases. Section title: Discussion Educational score: 1.8385331630706787 Domain: biomedical Document type: Study Language: en When questioned about whether the use of AI in dentistry and medicine is exciting, (57%) of students found the use of AI diagnosis exciting. The same opinion was reported by Turkish and Saudi students ( 51% and 47.3%) respectively. Section title: Discussion Educational score: 2.2413265705108643 Domain: biomedical Document type: Other Language: en AI systems are starting to provide new insights into healthcare and play a significant role in the diagnosis and prognosis of diseases. These algorithms examine enormous volumes of medical data to find connections and patterns that would be difficult for humans to find . In this term, 33% of the students agreed with AI's definitive role in disease prediction. Also, students in Turkey , Saudi Arabia , and India agreed that AI can be employed as a prognostic way to predict disease and decide whether there is a recovery chance. Section title: Discussion Educational score: 3.5629196166992188 Domain: biomedical Document type: Study Language: en It was generally agreed that AI could be used for the diagnosis of dental caries, periodontal diseases, soft tissue lesions, and pathologies in the jaws radiographically (58%, 56%, 49%, and 51% agreement, respectively). This was in accordance with Turkish , Saudi , and Indian students , who thought that AI could be used for radiographic diagnosis of tooth caries, periodontal diseases, and the diagnosis of soft tissue. In addition, the majority of participants (58%) think that AI could be useful in diagnosis and treatment planning in dentistry. Close responses were reported in Turkey (57.2%), Saudi Arabia (44.2%) , and much higher in India (88.69%). Section title: Discussion Educational score: 3.71421217918396 Domain: biomedical Document type: Study Language: en According to the systematic reviews of Khanagar,2021 and Khan, 2024 , AI is revolutionary in terms of delivering reliable data for forensic scientific decision-making. AI models can be useful tools for identifying victims of mass disasters and as an additional aid in medico-legal situations while concurrently reducing the time required and the risk of human error. By minimizing the effect of human factors, AI can contribute to more reliable and reproducible outcomes. In this study (44%) of participants agreed on AI's usefulness in forensic dentistry. This was in accordance with studies by Yüzbaşıoğlu, 2020 (52.1%), Khanagar et al., 2021 (38.3%), and Murali et al., 2023 (90.43%). Section title: Discussion Educational score: 2.2613823413848877 Domain: biomedical Document type: Study Language: en The wish to integrate and receive more training in AI applied to dentistry in undergraduate and postgraduate dental training was expressed by (49%) and (52%) respectively of participants. One possible explanation for this could be that undergraduate dental students are eager to learn about new dental technology that has the potential to improve treatment outcomes. There was almost universal agreement that AI should be incorporated into the undergraduate and postgraduate curriculums of dental schools. Section title: Discussion Educational score: 3.1965253353118896 Domain: biomedical Document type: Study Language: en The majority of the students (96%) in Elhijazi and Benyahya, 2023 , (85.43%) in the Murali et al., 2023 , and ( 80%) in Kalaimani et al., 2023 studies wished to receive more in-depth training in AI applied to dentistry. Also, (79.80% and 74.60%, respectively) of participants in the Yüzbaşıoğlu, 2020 study granted that subjects about AI should take part in undergraduate and postgraduate dental education. Moreover (59%) of students in Aldowah et al., 2024 and almost half of the participants in Jeong et al., 2024 (49%) studies believed that AI should be included in dental curricula. Section title: Discussion Educational score: 2.3948419094085693 Domain: biomedical Document type: Study Language: en Finally, this study is the first attempt to evaluate Egyptian students’ knowledge and perceptions of AI and can serve as a basis for future studies on the subject and for assessing the long-term impact of the integration of artificial intelligence into the educational curricula of dental students. However, the participants were recruited from only two universities, therefore, the chosen participants may not be appropriate representatives of dental students. Future surveys are necessary to monitor shifts in perception over time and give in-depth analytic data, especially considering how quickly artificial intelligence is developing. Section title: Conclusions Educational score: 2.2736146450042725 Domain: biomedical Document type: Study Language: en According to the outcomes of this study, a slight majority of dental students were knowledgeable about AI and aware of its usage in dentistry. Students consider the use of AI diagnosis exciting and believe in its pivotal role in disease prediction. Including, enhancing, and increasing AI training in dental schools is necessary. | Other | biomedical | en | 0.999996 |
PMC11697764 | Section title: Introduction Educational score: 3.5052812099456787 Domain: biomedical Document type: Review Language: en Recently, there has been a surge in HIV cure research aimed at either eliminating the virus from the body (HIV eradication, clearance cure) or ART-free durable control of the virus (functional cure, HIV suppression). 1 While much of this research focuses on biomedical, translational, and clinical sciences, the International AIDS Society (IAS) also emphasizes the importance of social engagement, particularly the engagement of affected communities, including people with HIV, their partners, and other key populations including GBMSM. 1 Section title: Introduction Educational score: 3.978523015975952 Domain: biomedical Document type: Review Language: en The emphasis on community engagement reflects a broader trend within health psychology over the past 25 years, emphasizing social justice. 2 Community engagement prioritizes strategies that draw from communities’ strengths and needs, fostering co-learning environments where individuals gain knowledge, skills and influence, empowering them to play an active role in research and decision-making. 2 Recognized for its effectiveness in reducing health inequities and improving health outcomes, community engagement has become an important factor in health promotion and other health and social science disciplines. 2 , 3 Evidence from the early HIV epidemic illustrates how people with HIV gained a “seat at the table” by educating themselves and blending lived experiences with scientific reasoning to advocate for their rights [ 4 pp284]. Successful community engagement has prompted health authorities, including the WHO, to revise guidelines, such as expanding early access to ART, and has been essential in HIV vaccine development by managing expectations and enhancing trial acceptance. 5 Section title: Introduction Educational score: 3.9374611377716064 Domain: biomedical Document type: Review Language: en Contrastingly, inadequate community engagement in pre-exposure prophylaxis (PrEP) research has been linked to the premature termination of several clinical trials in the early 2000s, resulting in delays in implementation. 6 , 7 A meta-analysis further emphasized the importance of community involvement in PrEP adaptation, revealing that concerns about its efficacy and potential side effects were significant barriers to adoption. Additionally, it highlighted that awareness and knowledge are crucial enablers of PrEP uptake. 8 This underscores how overlooked community perspectives can hinder not only the progress of development but also play an important role in the adaptation and implementation of biomedical advances. Section title: Introduction Educational score: 4.046518325805664 Domain: biomedical Document type: Study Language: en Given these precedents, we contend that community engagement is also essential for the successful development and implementation of an HIV cure. 9 Health behavior models can offer valuable insights into how affected communities can be effectively engaged in HIV cure research. 10 The engagement process can be understood using stage models like the Precaution Adoption Process Model (PAPM), which outlines stages from being ‘unaware of the issue’ to ‘aware but not personally engaged,’ progressing to ‘engaged and deciding what to do,’ and moving toward ‘planning to act,’ ‘acting,’ and ‘maintaining.' 11 Inspired by the first three stages, this study is one of the first to assess the current engagement with HIV cure research among affected communities in the Netherlands by evaluating their awareness, interest, and information-seeking behaviors. Section title: Introduction Educational score: 3.9490787982940674 Domain: biomedical Document type: Study Language: en While most studies focus on hypothetical scenarios, [e.g. Refs. 12 , 13 , 14 , 15 , 16 , 17 , 18 ] such as trial participation, few have explored actual community engagement in HIV cure research. 19 To our knowledge, only one study from Hong Kong explicitly assessed awareness of ART-free durable control. That study found that less than half of people with HIV included in their study were aware of ART-free durable control, with treatment-experienced participants being more likely to be aware. 20 Research from the United States and Brazil indicated that people had heard about HIV cure research, knew a cure was not yet available, or wanted to know more. 14 , 21 , 22 Furthermore, our qualitative research in the Netherlands among people with HIV, their partners, and GBMSM without HIV revealed a general awareness of HIV cure research, though active engagement was uncommon. 23 , 24 Section title: Introduction Educational score: 4.018362998962402 Domain: biomedical Document type: Study Language: en It also remains unclear who is aware, interested, and actively seeking information about HIV cure research, as engagement likely varies by age, gender, education, and context. 10 , 19 Recent research also suggests that HIV-related illness perceptions – encompassing views on illness effects, control, symptoms, concerns, understanding, duration, and causes – may influence engagement. 19 , 23 , 24 , 25 Therefore, in addition to evaluating current engagement, our study investigated the extent to which participant characteristics and HIV-related illness perceptions are associated with different stages of engagement. Lastly, we aimed to identify the specific characteristics and HIV-related illness perceptions that influence HIV cure research engagement among distinct communities, namely people with HIV and key populations without HIV. Section title: Design Educational score: 1.9479578733444214 Domain: biomedical Document type: Study Language: en This cross-sectional online survey on social engagement in HIV cure research in the Netherlands was developed with input from community and professional advisory boards and offered in Dutch and English between July 2023 and March 2024. Following ethical guidelines, participants were not required to complete all questions, only those for informed consent and bot detection, and could exit the survey at any time. The study was approved by the Ethical Review Board of the Faculty of Social and Behavioral Science, Utrecht University (FETC20-373), and the Ethical Review Committee Psychology and Neuroscience, Maastricht University . Section title: Participants and recruitment Educational score: 3.0222737789154053 Domain: biomedical Document type: Study Language: en Eligible participants included people with HIV and key populations without HIV (partners of people with HIV and GBMSM), aged 18 or older, residing in the Netherlands. Recruitment combined online (e.g., Instagram®, Grindr®) and offline strategies (magazines, community events, clinics), supported by stakeholders such as Hiv Vereniging , HIV care providers, Hello Gorgeous (part of national HIV alliance), Volle Maan (health communication agency), Amsterdam Municipal 10.13039/100018696 Health Services (GGD), and Maastricht University's HIV Lab. The final sample comprised 1077 participants from affected communities who completed sections on HIV cure engagement, participant characteristics, and HIV-related illness perceptions, including 499 people with HIV and 578 key populations (533 GBMSM and 45 partners). Section title: Participant characteristics Educational score: 1.8727864027023315 Domain: biomedical Document type: Study Language: en Participant characteristics included age, gender (cis-gender men = assigned male at birth and identify as men; cis-gender women = assigned female at birth and identify as women; other), sexual orientation (gay/lesbian; heterosexual; bisexual; other), educational attainment (with or without bachelor's degree), migration background (no migration background = born in the Netherlands with both parents also born in the Netherlands; first-generation migration background = not born in the Netherlands; second-generation migration background = born in the Netherlands with one or both parents born abroad), and steady relationship status (with or without committed partner [s]). Section title: Participant characteristics Educational score: 3.878098964691162 Domain: biomedical Document type: Study Language: en For people with HIV, additional data included the year of diagnosis, disclosure status (someone; no one), and current ART use (yes; no). We measured the frequency of ART-related side effects and missed doses over the past month on a 5-point scale (1 = never, 5 = very often). Other HIV-related characteristics included whether people with HIV had switched or stopped their ART regimen (yes; no), latest viral load (undetectable; detectable; unknown), recent CD4 T-cell count (<500; >500; unknown), AIDS diagnosis history (yes; no; unknown), and prior participation in HIV-related medical research (yes; no). For key populations, we gathered data on PrEP use (yes; no) and HIV testing frequency (every 3 months; 6 months; every year; less than once a year; never). Section title: HIV-related illness perceptions Educational score: 4.026634216308594 Domain: biomedical Document type: Study Language: en HIV-related illness perceptions were measured using a modified version of the Brief Illness Perception Questionnaire (Brief IPQ), 26 adapted for people with HIV and key populations ( Table S1 ). This scale evaluates seven dimensions: perceived consequences, perceived personal control, perceived treatment control, perceived identity, experienced concerns, experienced emotions, and perceived comprehensibility. The duration dimension from the Brief IPQ was excluded due to HIV's chronic nature. Participants responded on a 5-point scale (1 = not at all, 5 = very much). Higher scores for consequences, identity, concerns, and emotions indicated more threatening perceptions, while higher scores for control and comprehensibility reflected less threatening perceptions. Section title: HIV-related illness perceptions Educational score: 4.075916290283203 Domain: biomedical Document type: Study Language: en A principal factor analysis revealed two factors for people with HIV and three for key populations ( Table S1 ). For both groups, the primary factor centered on the perceived impact of HIV, including dimensions such as consequences, concerns, identity, and emotions. Notably, the identity dimension was integrated into this factor for people with HIV only. Internal consistency for this factor was strong (people with HIV: Cronbach's α = 0.82; key populations: Cronbach's α = 0.79). The second factor, which captured perceived control and comprehensibility, demonstrated low internal consistency (people with HIV: Cronbach's α = 0.41; key populations: Cronbach's α = 0.45). A third factor, identified only for key populations, focused solely on perceived identity. Due to the divergent factor structures between people with HIV and key populations and the unsatisfactory Cronbach's alpha for the second factor, all items were analyzed individually. Section title: HIV cure engagement Educational score: 3.0321199893951416 Domain: biomedical Document type: Study Language: en Guided by the first three stages of the PAPM, 11 we measured HIV cure engagement across three dimensions: awareness, interest, and information frequency. Awareness and interest were rated on a 5-point scale (1 = not at all, 5 = very much), while information-seeking frequency was reported on a 5-point scale (1 = never, 5 = often). Section title: Data analysis Educational score: 3.842761278152466 Domain: biomedical Document type: Study Language: en We conducted descriptive analyses to describe participant characteristics, HIV-related illness perceptions, and levels of engagement. Differences between people with HIV and key populations were examined using chi-square and ANOVA tests. Pearson correlation coefficients were calculated to explore relationships between awareness, interest, and information-seeking frequency for all affected communities and separately for people with HIV and key populations. Section title: Data analysis Educational score: 4.034531116485596 Domain: biomedical Document type: Study Language: en To evaluate how participant characteristics and HIV-related illness perceptions influence awareness, interest, and information-seeking frequency, we conducted three multivariable linear regression analyses. Bivariate linear regressions identified correlations among participant characteristics, HIV-related illness perceptions, and the three outcomes. To ensure inclusivity, all variables with a p < 0.10 from these analyses were incorporated into a standard multiple regression model. This process was repeated for people with HIV and key populations separately. Variables having p < 0.05 were deemed statistically significant. Since participants were not required to answer all questions (except for informed consent and bot detection), missing data were handled through listwise deletion. All analyses were conducted using SPSS version 29.0.0.0. Section title: Participant characteristics Educational score: 4.150650978088379 Domain: biomedical Document type: Study Language: en The mean age was 47 years ( SD = 14.14), with people with HIV significantly older ( M = 54, SD = 12.51) than key populations ( M = 42, SD = 13.34) ( Table 1 ). Most participants identified as cisgender men (91.8 %), but people with HIV had a higher proportion of non-cisgender men (13.0 %) compared to key populations (4.0 %). Approximately 64.0 % held a bachelor's degree, with key populations having a higher rate (69.9 %) than people with HIV (57.1 %). About 25 % reported a migration background, with similar rates across both groups. Roughly 80 % identified as gay or lesbian, with a higher proportion among key populations (84.4 %) than people with HIV (78.0 %). Approximately half reported having one or more steady partners, with no significant differences between groups. Table 1 Participant characteristics and HIV-related illness perceptions across people with HIV and key populations without HIV. Table 1 All affected communities People with HIV (N = 499) Key populations without HIV (N = 578) Chi-square or ANOVA results N (%) M(SD) N (%) M(SD) N (%) M(SD) χ 2 (df) or F (df), η 2 ₚ p-value Participant characteristics Age (in years) 47.45 (14.14) 53.54 (12.51) 42.18 (13.34) F = 205.77, η 2 ₚ = 0.161 <0.001 Gender χ2 (2) = 51.96 <0.001 Cis men 989 (91.8) 434 (87.0) 555 (96.0) Cis women 67 (6.2) 59 (11.8) 8 (1.4) Other 21 (1.9) 6 (1.2) 15 (2.6) Bachelor's degree χ2 (1) = 18.65 <0.001 No 385 (35.7) 212 (42.5) 173 (29.9) Yes 689 (64.0) 285 (57.1) 404 (69.9) Migration background 0.284 No 799 (74.2) 380 (76.2) 419 (72.5) First generation 106 (9.8) 42 (8.4) 64 (11.1) Second generation 171 (15.9) 77 (15.4) 94 (16.3) Sexual identity χ2 (3) = 70.53 <0.001 Gay/Lesbian 877 (81.4) 389 (78.0) 488 (84.4) Heterosexual 81 (7.5) 72 (14.4) 9 (1.6) Bisexual 79 (7.3) 24 (4.8) 55 (9.5) Other 40 (3.7) 14 (2.8) 26 (4.5) Steady partner(s) χ2 (1) = 6.11 0.013 No 486 (45.1) 214 (42.9) 292 (50.5) Yes 519 (52.7) 283 (56.7) 285 (49.3) HIV-related illness perceptions Consequence 2.84 (0.99) 2.73 (1.00) 2.95 (0.96) F = 11.28, η 2 ₚ = 0.011 <0.001 Personal control 3.62 (0.91) 3.51 (1.02) 3.73 (0.78) F = 16.16, η 2 ₚ = 0.015 <0.001 Identity 2.67 (0.99) 2.22 (0.97) 3.08 (0.80) F = 247.64, η 2 ₚ = 0.193 <0.001 Treatment control 4.26 (0.82) 4.54 (0.69) 4.02 (0.84) F = 116.68, η 2 ₚ = 0.099 <0.001 Concern 2.58 (1.00) 2.23 (0.96) 2.88 (0.94) F = 123.70, η 2 ₚ = 0.104 <0.001 Emotions 2.58 (1.07) 2.37 (1.04) 2.77 (1.07) F = 39.14, η 2 ₚ = 0.036 <0.001 Comprehensibility 3.29 (0.73) 3.56 (0.67) 3.06 (0.70) F = 130.13, η 2 ₚ = 0.109 <0.001 Note. Since participants were not required to answer all questions (except for informed consent and bot detection) degrees of freedom may differ for across variables. Section title: Participant characteristics Educational score: 3.8448078632354736 Domain: biomedical Document type: Study Language: en Most people with HIV were diagnosed between 1996 and 2020 (82.0 %), with 8.1 % diagnosed after 2020 and 9.9 % before 1996. Nearly all people with HIV (99.4 %) were on ART and demonstrated high adherence ( M = 4.58, SD = 0.73), with 98.8 % achieving an undetectable viral load. Additionally, 94.4 % had disclosed their HIV status to someone. Among key populations, 62.9 % did not take PrEP, and most tested every 3 or 6 months (55.8 %). Section title: HIV-related illness perceptions Educational score: 4.065057277679443 Domain: biomedical Document type: Study Language: en HIV-related illness perceptions differed significantly between people with HIV and key populations ( Table 1 ). Participants had a mean consequence score of 2.84 ( SD = 0.99), with people with HIV perceiving consequences as less threatening ( M = 2.73, SD = 1.00) compared to key populations ( M = 2.95, SD = 0.96). The mean personal control score was 3.62 ( SD = 0.91), with people with HIV reporting lower personal control ( M = 3.51, SD = 1.02) than key populations ( M = 3.73, SD = 0.78). For identity, the overall mean was 2.67 ( SD = 0.99), with people with HIV exhibiting less threatening perceptions ( M = 2.22, SD = 0.97) compared to key populations ( M = 3.08, SD = 0.80). Treatment control scores averaged 4.26 (SD = 0.82), with people with HIV reporting more control ( M = 4.54, SD = 0.69) than key populations ( M = 4.02, SD = 0.84). Concern levels averaged 2.58 ( SD = 1.00), with people with HIV showing less concern ( M = 2.23, SD = 0.96) than key populations ( M = 2.88, SD = 0.94). The mean score for emotions was 2.58 ( SD = 1.07), with people with HIV reporting less intense emotions ( M = 2.37, SD = 1.04) compared to key populations ( M = 2.77, SD = 1.07). Lastly, comprehensibility averaged 3.29 ( SD = 0.73), with people with HIV scoring higher ( M = 3.56, SD = 0.67) than key populations ( M = 3.06, SD = 0.70). Section title: HIV cure research engagement Educational score: 3.8673455715179443 Domain: biomedical Document type: Study Language: en Participants reported a mean awareness of 3.08 ( SD = 0.99) and a higher mean interest of 3.67 ( SD = 0.85), while the mean frequency of information-seeking was lower at 2.33 ( SD = 0.97) . People with HIV scored higher than key populations in awareness ( F = 42.67, η 2 ₚ = 0.038, p < 0.001), interest ( F = 76.76, η 2 ₚ = 0.067, p < 0.001), and information-seeking ( F = 55.89, η 2 ₚ = 0.049, p < 0.001). Fig. 1 Mean and standard error for the level of HIV cure engagement. Fig. 1 Section title: HIV cure research engagement Educational score: 4.045551300048828 Domain: biomedical Document type: Study Language: en Table 2 shows a weak positive correlation between awareness and interest across all affected communities ( r = 0.060, p < 0.05), which was not significant for people with HIV and key populations. In contrast, awareness had a strong correlation with information-seeking frequency across all communities ( r = 0.500, p < 0.001), as well as for people with HIV ( r = 0.433, p < 0.001) and key populations (r = 0.517, p < 0.001). Additionally, interest significantly correlated with information-seeking frequency across all communities ( r = 0.321, p < 0.001), with slightly stronger correlations among people with HIV ( r = 0.336, p < 0.001) than key populations ( r = 0.228, p < 0.001). Table 2 Pearson correlations for engagement variables. Table 2 1 2 3 All affected communities People with HIV Key populations All affected communities People with HIV Key populations All affected communities People with HIV Key populations 1. Awareness – – – 2. Interest 0.060* 0.006 0.027 – – – 3. Information-seeking frequency 0.500*** 0.433*** 0.517*** 0.321*** 0.336*** 0.228*** – – – p <.05 ∗∗p < .01 ∗∗∗p<0.001 Section title: Awareness Educational score: 4.164261817932129 Domain: biomedical Document type: Study Language: en Awareness among affected communities was significantly higher in older participants ( B = 0.007, SE = 0.002), non-cisgender men ( B = 0.187, SE = 0.078), and those with greater perceived personal ( B = 0.095, SE = 0.034) and treatment control ( B = 0.078, SE = 0.038) over HIV, as well as higher perceived comprehensibility of HIV ( B = 0.474, SE = 0.043) ( Table 3 ). Table 3 Bivariate and multivariate regression analysis of the level of HIV cure awareness, interest, and information seeking among all affected communities. Table 3 Awareness Interest Information seeking Bivariate Analyses Multivariate analysis (N = 993) Bivariate Analyses Multivariate analysis (N = 993) Bivariate Analyses Multivariate analysis Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Participant characteristics HIV-status Ref. People with HIV −0.389 (0.059)∗∗∗ 0.010 (0.077) −0.378 (0.051)∗∗∗ −0.432 (0.063)∗∗∗ −0.502 (0.057)∗∗∗ −0.357 (0.074)∗∗∗ Age (in years) 0.012 (0.002)∗∗∗ 0.007 (0.002)∗∗ −0.001 (0.002) 0.007 (0.002)∗∗∗ 0.005 (0.002)∗ Gender Ref. cisgender male 0.189 (0.084)∗ 0.187 (0.078)∗ 0.150 (0.072)∗ 0.096 (0.068) 0.242 (0.082)∗∗ 0.014 (0.080) Bachelor's degree Ref. No 0.064 (0.063) −0.005 (0.054) −0.124 (0.062)∗ −0.157 (0.061)∗ Migration background Ref. No −0.011 (0.040) 0.147 (0.034)∗∗∗ 0.089 (0.034)∗∗ 0.170 (0.039)∗∗∗ 0.123 (0.039)∗∗ Sexual identity: Ref: gay/lesbian −0.044 (0.039) −0.040 (0.034) 0.083 (0.038)∗ 0.055 (0.038) Partner(s): Ref. No 0.196 (0.060)∗∗ 0.098 (0.058) 0.135 (0.052)∗∗ 0.124 (0.050)∗ 0.145 (0.059)∗ 0.118 (0.057)∗ HIV-related illness perceptions Consequence −0.081 (0.031)∗∗ −0.032 (0.038) 0.125 (0.026)∗∗∗ −0.008 (0.033) 0.087 (0.030)∗∗ −0.032 (0.037) Personal control 0.164 (0.033)∗∗∗ 0.095 (0.034)∗∗ −0.063 (0.029)∗ −0.002 (0.030) 0.018 (0.033) Identity −0.143 (0.031)∗∗∗ −0.065 (0.034) −0.044 (0.027) + −0.022 (0.030) −0.102 (0.030)∗∗∗ −0.080 (0.034)∗ Treatment control 0.267 (0.036)∗∗∗ 0.078 (0.038)∗ 0.094 (0.032)∗∗ 0.033 (0.033) 0.137 (0.036)∗∗∗ 0.009 (0.037) Concern −0.141 (0.030)∗∗∗ −0.008 (0.040) 0.139 (0.026)∗∗∗ 0.150 (0.035)∗∗∗ 0.110 (0.029)∗∗∗ 0.190 (0.040)∗∗∗ Emotions −0.081 (0.028)∗∗ 0.033 (0.035) 0.154 (0.024)∗∗∗ 0.125 (0.031)∗∗∗ 0.102 (0.028)∗∗∗ 0.090 (0.035)∗ Comprehensibility 0.544 (0.038)∗∗∗ 0.474 (0.043)∗∗∗ 0.192 (0.035)∗∗∗ 0.116 (0.038)∗∗ 0.331 (0.040)∗∗∗ 0.292 (0.043)∗∗∗ p < 0.10 + , p < 0.05∗, p < 0.01∗∗p < 0.001∗∗∗. Note. Since participants were not required to answer all questions (except for informed consent and bot detection), missing data were handled through listwise deletion resulting in varying participant numbers per outcome. Bold means statistically significant in the multivariate model. Awareness R 2 = 0.205; Interest R 2 = 0.160; Interest R 2 = 0.181. Section title: Awareness Educational score: 4.138236045837402 Domain: biomedical Document type: Study Language: en For people with HIV, greater awareness correlated with higher perceived personal control ( B = 0.157, SE = 0.044), increased HIV-related comprehensibility ( B = 0.440, SE = 0.052), and better self-reported adherence ( B = 0.149, SE = 0.054) ( Table 4 ). Among key populations, greater awareness was associated with older age ( B = 0.008, SE = 0.003), increased perceived comprehensibility ( B = 0.440, SE = 0.049), and higher treatment control ( B = 0.154, SE = 0.049). Key populations who tested more regularly ( B = −0.051, SE = 0.022) and reported fewer concerns about HIV ( B = −0.091, SE = 0.042) also showed greater awareness ( Table 5 ). Table 4 Bivariate and multivariate regression analysis of HIV cure awareness, interest and information seeking among people with HIV. Table 4 Awareness Interest Information seeking Bivariate Analyses Multivariate analysis (N = 486) Bivariate Analyses Multivariate analysis (N = 474) Bivariate Analyses Multivariate analysis (N = 478) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Participant characteristics Age (in years) 0.002 (0.003) −0.007 (0.003)∗ 0.001 (0.003) −0.001 (0.004) Gender Ref. cisgender male 0.174 (0.110) 0.043 (0.096) 0.169 (0.117) Bachelor's degree Ref. No 0.009 (0.085) −0.040 (0.075) −0.073 (0.091) Migration background Ref. No −0.081 (0.057) 0.154 (0.049)∗∗ 0.077 (0.053) 0.151 (0.060)∗ 0.096 (0.060) Sexual identity: Ref: gay/lesbian 0.019 (0.061) 0.052 (0.053) 0.218 (0.064)∗∗∗ 0.190 (0.063)∗∗ Partner(s): Ref. No 0.095 (0.085) 0.061 (0.075) 0.133 (0.091) Years of diagnosis 0.003 (0.005) 0.013 (0.004)∗∗ 0.009 (0.005) 0.014 (0.005)∗∗ 0.007 (0.005) On treatment Ref. Yes 1.053 (0.543) 0.800 (0.475) 1.407 (0.577)∗ 1.079 (0.542)∗ Side effects −0.023 (0.037) 0.049 (0.032) 0.044 (0.040) Adherence 0.152 (0.057)∗∗ 0.149 (0.054)∗∗ 0.064 (0.050) 0.036 (0.061) Viral Load Ref. undetectable −0.002 (0.316) −0.014 (0.275) −0.024 (0.337) CD4-count Ref. Less than 500 cells/mm 3 −0.076 (0.066) 0.049 (0.058) −0.090 (0.071) AIDS Ref. Yes −0.042 (0.097) 0.073 (0.085) 0.135 (0.103) Disclosure Ref. To someone −0.417 (0.182)∗ −0.241 (0.173) 0.022 (0.160) −0.334 (0.194) Participation in Medical trial Ref. Yes −0.222 (0.084)∗∗ −0.148 (0.080) 0.145 (0.073)∗ 0.023 (0.076) −0.034 (0.090) HIV-related illness perceptions Consequence −0.056 (0.042) 0.181 (0.036)∗∗∗ 0.095 (0.051) 0.109 (0.045)∗ −0.018 (0.59) Personal control −0.218 (0.052)∗ 0.157 (0.044)∗∗∗ −0.021 (0.036) 0.073 (0.044) + 0.096 (0.047)∗ Identity −0.088 (0.043)∗ −0.039 (0.049) 0.102 (0.038)∗∗ −0.023 (0.047) 0.062 (0.046) Treatment control 0.099 (0.040)∗∗∗ 0.049 (0.062) −0.078 (0.053) −0.062 (0.065) Concern −0.090 (0.044)∗ 0.063 (0.053) 0.226 (0.037)∗∗∗ 0.102 (0.050)∗ 0.227 (0.046)∗∗∗ 0.244 (0.060)∗∗∗ Emotions −0.078 (0.040) + −0.007 (0.049) 0.206 (0.034)∗∗∗ 0.093 (0.050) 0.150 (0.043)∗∗∗ 0.049 (0.057) Comprehensibility 0.494 (0.059)∗∗∗ 0.440 (0.062)∗∗∗ 0.019 (0.055) 0.289 (0.065)∗∗∗ 0.336 (0.065)∗∗∗ p < 0.10 + , p < 0.05∗, p < 0.01∗∗p < 0.001∗∗∗. Note. Since participants were not required to answer all questions (except for informed consent and bot detection), missing data were handled through listwise deletion resulting in varying participant numbers per outcome. Bold means statistically significant in the multivariate model. Awareness R 2 = 0.174; Interest R 2 = 0.111; Interest R 2 = 0.153. Table 5 Bivariate and multivariate regression analysis of HIV cure awareness, interest and information seeking among key populations without HIV. Table 5 Awareness Interest Information seeking Bivariate Analyses Multivariate analysis (N = 534) Bivariate Analyses Multivariate analysis (N = 553) Bivariate Analyses Multivariate analysis (N = 526) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Unstandardized Beta (SE) Participant characteristics Age (in years) 0.011 (0.003)∗∗∗ 0.008 (0.003)∗ −0.008 (0.003)∗∗ −0.006 (0.003)∗ 0.000 (0.003) Gender Ref. cisgender male 0.090 (0.124) 0.156 (0.103) 0.172 (0.109) Bachelor's degree Ref. No 0.140 (0.091) 0.136 (0.075) + 0.033 (0.076) −0.039 (0.080) Migration background Ref. No 0.060 (0.055) 0.155 (0.045)∗∗∗ 0.087 (0.046) 0.205 (0.048)∗∗∗ 0.131 (0.049)∗∗ Sexual identity: Ref: gay/lesbian −0.078 (0.050) −0.097 (0.042)∗ −0.089 (0.041)∗ 0.006 (0.044) Partner(s): Ref. No 0.230 (0.083)∗∗ 0.089 (0.080) 0.123 (0.069) + 0.164 (0.069)∗ 0.086 (0.073) PrEP Ref. Yes −0.350 (0.085)∗∗∗ −0.066 (0.104) −0.262 (0.071)∗∗∗ −0.178 (0.090)∗ −0.237 (0.075)∗∗ −0.080 (0.096) HIV testing Ref. every 3 months −0.078 (0.018)∗∗∗ −0.051 (0.022)∗ −0.045 (0.015)∗∗ 0.000 (0.019) −0.060 (0.016)∗∗∗ −0.027 (0.020) HIV-related illness perceptions Consequence −0.067 (0.043) 0.115 (0.036)∗∗ −0.102 (0.046)∗ 0.119 (0.038)∗∗ −0.023 (0.049) Personal control 0.159 (0.054)∗∗ −0.015 (0.053) −0.064 (0.045) 0.021 (0.048) Identity −0.049 (0.054) −0.017 (0.044) −0.053 (0.047) Treatment control 0.248 (0.048)∗∗∗ 0.154 (0.049)∗∗ 0.084 (0.041)∗ 0.038 (0.042) 0.112 (0.043)∗ 0.081 (0.044) Concern −0.085 (0.044) + −0.091 (0.042)∗ 0.222 (0.036)∗∗∗ 0.178 (0.051)∗∗∗ 0.199 (0.038)∗∗∗ 0.120 (0.054)∗ Emotions −0.023 (0.040) 0.185 (0.032)∗∗∗ 0.104 (0.040)∗∗ 0.155 (0.034)∗∗∗ 0.075 (0.042) Comprehensibility 0.527 (0.56)∗∗∗ 0.440 (0.058)∗∗∗ 0.202 (0.049)∗∗∗ 0.132 (0.052)∗ 0.211 (0.052)∗∗∗ 0.131 (0.054)∗ p < 0.10 + , p < 0.05∗, p < 0.01∗∗p < 0.001∗∗∗. Note. Since participants were not required to answer all questions (except for informed consent and bot detection), missing data were handled through listwise deletion resulting in varying participant numbers per outcome. Bold means statistically significant in the multivariate model. Awareness R 2 = 0.196; Interest R 2 = 0.142; Interest R 2 = 0.099. Section title: Interest Educational score: 3.9607255458831787 Domain: biomedical Document type: Study Language: en Interest in HIV cure research among affected communities was significantly higher among people with HIV ( B = −0.432, SE = 0.063), those with a migration background ( B = 0.089, SE = 0.034), and individuals with steady partners ( B = 0.124, SE = 0.050). Participants expressing greater concerns ( B = 0.150, SE = 0.035), negative emotions about HIV ( B = 0.125, SE = 0.031), and a higher comprehensibility of HIV ( B = 0.116, SE = 0.038) also showed increased interest ( Table 3 ). Section title: Interest Educational score: 3.896275758743286 Domain: biomedical Document type: Study Language: en Among people with HIV, only those with greater concerns ( B = 0.102, SE = 0.050) demonstrated significantly higher interest ( Table 4 ). In key populations, younger individuals ( B = −0.006, SE = 0.003), gay or lesbian individuals ( B = −0.089, SE = 0.041), those without partners ( B = 0.164, SE = 0.069), and those on PrEP ( B = −0.178, SE = 0.090) exhibited greater interest. Additionally, key populations who perceived less consequence from HIV ( B = −0.102, SE = 0.051), had more concerns ( B = 0.178, SE = 0.051), and higher HIV-related comprehensibility ( B = 0.132, SE = 0.052) were more interested ( Table 5 ). Section title: Information seeking Educational score: 4.0161542892456055 Domain: biomedical Document type: Study Language: en Among affected communities, information-seeking frequency was significantly higher among older ( B = 0.005, SE = 0.002), people with HIV ( B = −0.357, SE = 0.074), individuals without a bachelor's degree ( B = −0.078, SE = 0.061), those with a migration background ( B = 0.096, SE = 0.039), and those with one or more partners ( β = 0.080, SE = 0.057). It was also associated with a stronger HIV identity ( B = −0.082, SE = 0.034), greater concerns ( B = 0.190, SE = 0.040), negative emotions ( B = 0.090, SE = 0.035), and increased HIV comprehensibility ( B = 0.292, SE = 0.043) ( Table 3 ). Section title: Information seeking Educational score: 4.022604942321777 Domain: biomedical Document type: Study Language: en For people with HIV, information-seeking was notably higher among non-gay/lesbian participants ( B = 0.190, SE = 0.063), those with more concerns ( B = 0.244, SE = 0.060), higher perceived personal control ( B = 0.096, SE = 0.047), and greater HIV comprehensibility ( B = 0.336, SE = 0.065). Participants not on treatment ( B = 1.079, SE = 0.542) were also more likely to seek information about HIV cure research ( Table 4 ). In key populations, greater information-seeking was found among individuals with a migration background ( B = 0.131, SE = 0.049), those expressing more concerns ( B = 0.120, SE = 0.054), and those with higher perceived comprehensibility ( B = 0.131, SE = 0.054) ( Table 5 ). Section title: Discussion Educational score: 4.042851448059082 Domain: biomedical Document type: Study Language: en This research is one of the first to assess the non-hypothetical engagement of affected communities in HIV cure research by evaluating their awareness, interest, and information-seeking behavior, inspired by the early stages mapped out in the (PAPM). 11 We also investigated which affected communities, participant characteristics, and HIV-related illness perceptions were associated with these three stages. Lastly, we examined if associated characteristics differed between the two groups of affected communities included in this research: people with HIV and key populations. Section title: Discussion Educational score: 4.080722808837891 Domain: biomedical Document type: Study Language: en Our findings indicate that engagement with HIV cure research in affected communities is largely passive, characterized by low active information-seeking despite notable interest levels. Correlations between awareness and interest were weak across all communities and not significant among people with HIV and key populations, challenging the PAPM's assumption that greater awareness leads to higher interest. 10 , 11 However, higher interest was associated with more frequent information-seeking, indicating that survey participation may have increased awareness and stimulated interest in HIV cure research. Alternatively, the lack of a clear definition of HIV cure research may have led to uncertainty or underconfidence in participants' self-reported awareness, consistent with previous research in the Netherlands that highlighted uncertainty between general awareness and detailed understanding. 24 , 27 Future research should assess awareness of specific HIV cure developments for clearer insights. Section title: Discussion Educational score: 3.26747989654541 Domain: biomedical Document type: Study Language: en People with HIV showed greater engagement across all stages compared to key populations, but HIV status did not significantly influence awareness. Instead, awareness was linked to individuals' perceived comprehensibility and control over HIV, which also influenced their interest and information-seeking frequency. This may be due to individuals who perceive higher comprehensibility and control over HIV having a stronger sense of agency and a desire to manage their health, prompting them to seek and retain more information about ongoing advancements in HIV cure research. 28 Section title: Discussion Educational score: 3.820568323135376 Domain: biomedical Document type: Study Language: en Awareness of HIV cure research was also influenced by age and gender; however, older individuals and women did not show a corresponding increase in interest. This discrepancy may stem from their greater involvement in community settings, 2 , 29 which enhances overall knowledge, including HIV cure awareness. For instance, the women's group 'Posidivas' has recently gained attention, 30 and since 2022, the Hiv Vereniging has been chaired by a cisgender woman, 31 fostering engagement and knowledge among women. Similarly, the ‘Long Term Survivors’, those diagnosed before 1996 and an active group within the community, 32 likely keeps members informed. This aligns with research showing that HIV activists are often more willing to participate in cure trials. 15 Further research should explore how community connectedness relates to HIV cure awareness and engagement. Section title: Discussion Educational score: 3.684933662414551 Domain: biomedical Document type: Study Language: en Subgroup analyses indicated that ART adherence among people with HIV and frequent testing among key populations were linked to greater awareness. This suggests that individuals who manage their health, 28 and engage regularly with healthcare professionals are more aware, a finding supported by studies highlighting the critical role of healthcare professionals in promoting HIV cure engagement. 20 , 33 , 34 , 35 Section title: Discussion Educational score: 4.020380020141602 Domain: biomedical Document type: Study Language: en In contrast to awareness, both interest and information-seeking frequency were significantly higher among people with HIV. Individuals with greater concerns and negative emotions about HIV, a migration background, or steady relationships also demonstrated increased interest and information-seeking, suggesting that a heightened perceived need for an HIV cure drives these behaviors. People with HIV likely feel a stronger need for a cure due to its significant impact on their lives, 24 , 36 as do those with heightened concerns and negative emotions. 24 Individuals from migration backgrounds may face increased stigma, 37 leading to poorer psychosocial and clinical outcomes, 38 , 39 which heightens their perceived need for a cure. 24 For those in steady relationships, a cure may be desired as it may alleviate transmission concerns. 23 , 36 Future research should explore how perceived needs influence interest and information-seeking behavior. Section title: Discussion Educational score: 3.4624855518341064 Domain: biomedical Document type: Study Language: en Additionally, interest levels among key populations were influenced by younger age, identifying as gay, and PrEP use. Previous research suggests that the potential for an HIV cure to enhance sexual freedom, by eliminating transmission risk and reducing HIV-related anxieties, may drive this interest. 23 , 36 Further investigation is needed to assess the extent to which the prospect of increased sexual freedom impacts interest in HIV cure research, including potential concerns about the risk of reinfection post-cure. Section title: Discussion Educational score: 2.8253254890441895 Domain: biomedical Document type: Study Language: en Lastly, our findings indicated that individuals without a bachelor's degree sought information about HIV cure research more frequently. Subgroup analyses revealed that people with HIV who are not on treatment and those who do not identify as gay also sought information more often. However, these groups did not demonstrate higher interest levels, suggesting that the available resources may not adequately meet their needs, prompting them to seek additional information. 40 Further research is needed to identify community members facing challenges in accessing HIV cure information and to tailor resources accordingly. Section title: Discussion Educational score: 4.054593086242676 Domain: biomedical Document type: Study Language: en Our study is among the first to evaluate non-hypothetical engagement in HIV cure research across diverse affected communities. However, several limitations should be noted. Although we highlighted the importance of HIV-related illness perceptions, our measurement tool showed inconsistent factor loadings and low internal consistency, likely due to high participant diversity and varied responses. For example, identity emerged as a distinct factor for key populations, rather than being part of the perceived impact factor, as it was for people with HIV. This may be because key populations have indirect experiences with HIV, leading to more varied and potentially unrealistic or threatening perceptions. 23 , 41 Future studies should investigate how HIV-related illness perceptions form and the factors that shape them to refine the adapted Brief IPQ for both people with HIV and key populations. Section title: Discussion Educational score: 3.371798276901245 Domain: biomedical Document type: Study Language: en Despite our sample's diversity, we may not have fully captured the range of experiences within the people with HIV and key populations in the Netherlands, particularly because partners of people with HIV were notably underrepresented. This limits our ability to draw specific conclusions about their perspectives, which likely differed from GBMSM. 24 Future research should address this gap. Although we received input from advisory boards and used inclusive materials like information videos, the abstract nature of HIV cure research may have hindered recruitment, especially among individuals without bachelor's degrees. Future studies should consider assisting underserved communities in completing surveys to ensure more diverse participation. Additionally, while the Dutch context may resonate with experiences in other high-income countries, these findings may not be applicable in settings lacking access to ART or PrEP. Future research should explore these dynamics in diverse global contexts to enhance the broader applicability of the findings. Section title: Discussion Educational score: 3.180927038192749 Domain: biomedical Document type: Other Language: en In conclusion, while moderate awareness exists—driven by knowledge, community ties, and healthcare interactions—engagement remains passive, with limited information-seeking. However, significant interest, fueled by the perceived need for a cure, is evident. To foster the active and meaningful engagement advocated by the IAS HIV cure agenda, HIV communities, researchers, and healthcare providers must enhance communication efforts to make information on HIV cure development more accessible, especially for those not connected to community organizations. Section title: CRediT authorship contribution statement Educational score: 0.9948692917823792 Domain: other Document type: Other Language: en Maaike A.J. Noorman: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Visualization, Writing – original draft, Resources. John B.F. de Wit: Conceptualization, Funding acquisition, Methodology, Supervision, Writing – review & editing. Tamika A. Marcos: Investigation, Project administration, Resources, Writing – review & editing. Sarah E. Stutterheim: Conceptualization, Funding acquisition, Supervision, Writing – review & editing. Thijs Albers: Investigation, Resources, Writing – review & editing. Kai J. Jonas: Conceptualization, Funding acquisition, Investigation, Supervision, Writing – review & editing. Chantal den Daas: Conceptualization, Funding acquisition, Methodology, Supervision, Writing – review & editing. Section title: Declaration of generative AI and AI-assisted technologies in the writing process Educational score: 0.9677923917770386 Domain: other Document type: Other Language: en During the preparation of this work the authors used ChatGPT and Grammerly in order to enhance clarity and conciseness in writing. After using this, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication . Section title: Funding Educational score: 1.026240348815918 Domain: other Document type: Other Language: en Aidsfonds funded this research under Grant P-53001. Section title: Declaration of competing interest Educational score: 1.0098649263381958 Domain: other Document type: Other Language: en The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors report there are no direct competing interests to disclose. However, two of the authors (Sarah E. Stutterheim and Kai J. Jonas) received funding, unrelated to this topic from 10.13039/100005564 Gilead , 10.13039/100030732 MSD , and 10.13039/100010877 ViiV Healthcare . | Review | biomedical | en | 0.999996 |
PMC11697765 | Section title: Introduction Educational score: 3.9930317401885986 Domain: biomedical Document type: Study Language: en Pubertal development is controlled by the hypothalamic pituitary gonadal (HPG) axis . The HPG axis initiates development of the reproductive system at mid-gestation, until after the first year when it becomes inactive . The HPG axis is then reactivated when pubertal maturation begins . This timetable of changes suggests possible prenatal intervention in the reawakening of the HPG axis during puberty. The pubertal development process may be affected by environmental stimuli and cellular metabolites including those of sex hormones . Section title: Introduction Educational score: 4.0987043380737305 Domain: biomedical Document type: Study Language: en In animals, growth and age of pubertal onset can be manipulated in ways that include changing diets and injecting hormones during the prenatal period. Evidence from such studies suggests that fetal nutrient and/or hormonal exposures may affect fetal development. For example, there is an increased risk of fetal growth restriction (FGR) in suboptimal environments , such as those with poor maternal nutrition. This may lead to low birth weight and small-for-gestational age (SGA). If there is catch-up growth (reflecting increased growth rate after a period of growth delay during early childhood after such exposures, the growth and its related metabolic alterations may expedite the reactivation of the HPG axis and pubertal onset . Section title: Introduction Educational score: 4.096410751342773 Domain: biomedical Document type: Study Language: en Several nutrients such as fatty acids, iron, iodine, zinc, and B-vitamins play important roles in nerve tissue functions and metabolic processes , which may affect the activity of the HPG axis and hence, pubertal development. The brain is lipid rich with its structural components dominated by long-chain PUFA such as DHA . Therefore, insufficient intake of the essential fatty acids alpha-linolenic acid and linoleic acid, which can be converted into DHA and arachidonic acid, respectively, may contribute to impaired brain function . Prenatal malnutrition may alter the expected timeline and function of the HPG axis, and consequently shift pubertal development. Section title: Introduction Educational score: 4.086681365966797 Domain: biomedical Document type: Study Language: en In low-income settings, cereals and tubers are common staples consumed by pregnant and lactating females; these staples are of low nutrient quality . Multiple micronutrient (MMN) deficiencies, associated with consumption of diets dominated by these foods, are associated with poor maternal and child outcomes such as FGR and poor growth and development among children [ , , ]. The International Lipid-based Nutrient Supplements (iLiNS) Project team developed small-quantity lipid-based nutrient supplements (SQ-LNS) (20 g/d) for enriching the usual diets of pregnant and lactating females and infants with micronutrients, essential fatty acids, and small amounts of energy (118 kcal/d) and high-quality protein (2.6 g/d) during the first 1000 d. At least 16 trials have been conducted in 10 countries in which versions of SQ-LNS were provided either to infants only during the period 6–23 mo of age [ , , , , , , , , , , , ], or to both mothers and infants [ , , , ] during pregnancy, lactation, and infancy. In meta-analyses [ , , ], the provision of SQ-LNS to infants aged 6–24 mo was associated with positive anthropometric outcomes, including a reduction in the prevalence of stunting/severe stunting, wasting/severe wasting, and underweight. There was a lower prevalence of anemia, when compared with the provision of no intervention. Section title: Introduction Educational score: 4.036757469177246 Domain: biomedical Document type: Study Language: en Early pubertal timing has been associated with development of metabolic syndrome and cancers of the reproductive system in later life, whereas late pubertal timing has been linked to psychosocial difficulties . In Sub-Saharan Africa, previous studies have shown associations of stunting and underweight with later pubertal development [ , , ]. On the other hand, there is the increasing prevalence of earlier onset of puberty over the past 2–3 decades, parallel to the global increasing prevalence of obesity. In Ghana, prior studies have shown a decline in age at menarche by 9–15 mo with obesity and high socioeconomic status as predictive factors among urban schoolgirls . These suggest that nutritional factors and their corresponding endogenous metabolic and hormonal signals play relevant roles in pubertal development , which is consistent with studies showing positive associations of anthropometric measurements with pubertal development . Section title: Introduction Educational score: 4.060442924499512 Domain: biomedical Document type: Study Language: en In the iLiNS-DYAD trial in Ghana, we demonstrated that SQ-LNS provided during the first 1000 d positively impacted birth size as well as subsequent growth and socioemotional outcomes. In this study, we assessed whether there were intervention group differences in pubertal status at 9–11 and 11–13 y. We hypothesized that the SQ-LNS group would be more advanced in pubertal development than the non-LNS group at these ages . We also tested whether sex, household asset index, or birth order moderated the effect of the intervention on pubertal stage. We did not set a priori hypotheses for effect modification. Finally, we investigated whether the effect of the intervention on pubertal stage was mediated by birth weight for gestational age z-score or BMI z-score (BMIZ) at 4–6, 9–11, and 11–13 y. Section title: Summary of the original iLiNS-DYAD trial Educational score: 3.3325865268707275 Domain: biomedical Document type: Study Language: en The iLiNS-DYAD Ghana study was a randomized, partially double-blind, controlled trial that compared 3 nutrient supplements. The trial was conducted in peri-urban settlements in the Yilo Krobo and Lower Manya Krobo districts of the Eastern region of Ghana, ∼70 km north of Accra (the capital of Ghana). Primary caregiver written informed consent was obtained prior to data collection. Each caregiver was visited at home and visited our project office, whereas we collected data on sociodemographic information using interviewer-administered questionnaires. Details of the trial have been previously reported elsewhere and are summarized herein. Section title: Study participants and procedure Educational score: 3.439666986465454 Domain: biomedical Document type: Other Language: en In the main iLiNS-DYAD randomized controlled trial (RCT), females were eligible to participate if they were ≥18 y of age and ≤20 wk gestation. Females were excluded for the following reasons: antenatal card indicated HIV infection, asthma, epilepsy, tuberculosis, or any malignancy; known milk or peanut allergy; not residing in the study area; intention to relocate within the next 2 y; unwillingness to consent to participate, receive home visits from fieldworkers or take the study supplement; and participation in another trial. Section title: Study participants and procedure Educational score: 4.183767318725586 Domain: biomedical Document type: Study Language: en Pregnant females attending antenatal clinics in 4 main health facilities in the study area were recruited from December 2009 to December 2011. Eligible females were visited at home and those who met the inclusion criteria and provided informed consent were scheduled for a clinic visit for baseline assessments. Enrolled females were randomly assigned to 1 of 3 supplementation groups ( Table 1 ) : 1 ) daily 60 mg iron and 400 μg folic acid (IFA) during pregnancy, and 200 mg calcium (Ca) only during the first 6 mo postpartum, with no supplementation for offspring during infancy; 2 ) daily MMN (1–2 Recommended Dietary Allowance of 18 vitamins and minerals) during pregnancy and the first 6 mo postpartum, with no supplementation for offspring during infancy, and 3 ) daily 20 g SQ-LNS during pregnancy and the first 6 mo postpartum (SQ-LNS during pregnancy and lactation contained similar vitamin and mineral content as the daily MMN, plus calcium, phosphorous, potassium, magnesium, and essential fatty acids), with SQ-LNS for offspring (20 g with 22 vitamins and minerals with concentrations based on Recommended Nutrient Intakes for infants) from 6 to 18 mo of age. Participants were aware whether they received SQ-LNS or a capsule but were blind to whether they received IFA or MMN. Field workers who assessed outcomes and collected other data were blind to the intervention groups. TABLE 1 Nutrient and energy contents of supplements used in the iLiNS trial in Ghana. TABLE 1 Ration per day IFA MMN Maternal SQ-LNS Child SQ-LNS 1 capsule 1 capsule 20-g sachet 20-g sachet Total energy (kcal) 0 0 118 118 Protein (g) 0 0 2.6 2.6 Fat (g) 0 0 10 9.6 Linoleic acid (g) 0 0 4.59 4.46 α-Linolenic acid, (g) 0 0 0.59 0.58 Vitamin A (μg RE) 0 800 800 400 Vitamin C (mg) 0 100 100 30 Vitamin B-1 (mg) 0 2.8 2.8 0.3 Vitamin B-2 (mg) 0 2.8 2.8 0.4 Niacin (mg) 0 36 36 4 Folic acid (μg) 400 400 400 80 Pantothenic acid (mg) 0 7 7 1.8 Vitamin B-6 (mg) 0 3.8 3.8 0.3 Vitamin B-12 (μg) 0 5.2 5.2 0.5 Vitamin D (mg) 0 10 10 5 Vitamin E (mg) 0 20 20 6 Vitamin K (μg) 0 45 45 30 Iron (mg) 60 20 20 6 Zinc (mg) 0 30 30 8 Copper (mg) 0 4 4 0.34 Calcium (mg) 0 0 280 280 Phosphorus (mg) 0 0 190 190 Potassium (mg) 0 0 200 200 Magnesium (mg) 0 0 65 40 Selenium (μg) 0 130 130 20 Iodine (μg) 0 250 250 90 Manganese (mg) 0 2.6 2.6 1.2 Abbreviations: IFA, iron and folic acid capsule; iLiNS, international lipid-based nutrient supplement; MMN, multiple micronutrient supplement capsule; SQ-LNS, small-quantity lipid-based nutrient supplement. Information from table previously published . Section title: Follow-up study design and methods Educational score: 4.029804229736328 Domain: biomedical Document type: Study Language: en Using participants’ addresses and telephone contacts from the original iLiNS-DYAD-Ghana trial, caregivers with surviving children were traced and invited to participate in this study. We obtained ethical approval for the current follow-up study from the Institutional Review Board of the University of California Davis and the Ghana Health Service Ethical Review Committee . Child written informed assent was obtained prior to data collection. Each child visited our project office while we collected data on pubertal stage using interviewer-administered questionnaires. At the 4–6-y follow-up, weight and height measurements were taken by trained anthropometrists as reported previously , and these measurements were repeated at 9–11 and 11–13 y. Pubertal status was assessed at 9–11 y and 11–13 y of age. Our targeted enrollment of 966 provided 80% power to detect a small effect size, that is, a mean difference between 2 groups of >0.2 SD for continuous outcomes at a significance level of P < 0.05. Section title: Assessment of outcome Educational score: 4.072205543518066 Domain: biomedical Document type: Study Language: en Participants responded to each item on the Petersen Pubertal Development Scale (PDS) score using a 4-point Likert scale that described the stage of 5 pubertal milestones each, for boys and girls. On the scale, 1 was defined as pubertal development not yet begun, 2 as barely started, 3 as definitely underway, and 4 as completed. In girls, we determined PDS score by self-report of breast development, menarche, growth spurt, skin changes, and body hair. In boys, we determined pubertal development by self-report of voice break, facial hair, growth spurt, skin changes, and body hair. A total score ranged from 5 to 20. We conducted a pilot study of 30 caregiver-child dyads in our study sample to assess test-retest reliability of the PDS score. Our pilot study showed that the 1-wk test-retest reliability ( N = 30; child report: r = 0.72; caregiver report: r = 0.70) of the PDS was good . We selected the child report, which had a higher test-retest reliability score, for assessing pubertal status. In addition, we adjusted the PDS score by age in a regression model, computed residuals and standardized to calculate age-adjusted PDS z-score (aPDSZ) as our outcome. Section title: Statistical analysis Educational score: 4.075624465942383 Domain: biomedical Document type: Study Language: en We posted a statistical analysis plan to Open Science Framework ( https://osf.io/7j368 ) before conducting analyses. All analyses were performed using R version 4.3.1 . All tests were 2-sided, at 95% confidence interval (CI) and a 5% level of significance following a complete case intention-to-treat framework. We planned to compare SQ-LNS compared with non-LNS (IFA + MMN) groups. Nevertheless, we first performed a sensitivity analysis comparing the IFA and MMN groups to confirm that combining the groups was reasonable. We examined whether children in the SQ-LNS and non-LNS groups were similar in baseline characteristics using descriptive statistics for each intervention group. To evaluate potential bias in the sample, we compared baseline characteristics between the sample included in the analyses and the sample enrolled in the main trial but lost to follow-up, using t tests for continuous variables and χ 2 tests for categorical variables. Section title: Statistical analysis Educational score: 4.078185081481934 Domain: biomedical Document type: Study Language: en To test our hypothesis that the SQ-LNS group was more advanced in pubertal stage than the non-LNS group at 9–11 and 11–13 y of age, we examined the difference between the SQ-LNS and non-LNS groups using analysis of covariance (ANCOVA) in minimally adjusted (with child sex) and covariate adjusted models. The prespecified covariates listed above were tested for associations with the aPDSZ. Significant ( P < 0.10) covariates were included in the adjusted ANCOVA model. Prespecified covariates were identified from previous studies and included sociodemographic background characteristics at baseline: maternal age, years of maternal education, maternal marital status, household asset index, household food insecurity, household improved water, household toilet facility, maternal prepregnancy BMI (kg/m 2 ), maternal height, maternal hemoglobin concentration, season of birth, birth order, and parity. Section title: Statistical analysis Educational score: 3.8669466972351074 Domain: biomedical Document type: Study Language: en In exploratory analyses, we tested potential effect modification by 3 prespecified variables: baseline household asset index, child sex, and birth order. We tested the interaction between each potential effect modifier and intervention groups in ANCOVA models. Significant interactions ( P < 0.10) were further examined with stratified analyses and regions of significance in stratified analyses . Section title: Statistical analysis Educational score: 4.070901870727539 Domain: biomedical Document type: Study Language: en We tested potential mediation of exposure effects by: 1 ) birth weight measured in grams and used to calculate birth weight for gestational age z-score, based on INTERGROWTH norms, to account for variations in birth weight by gestational age and child sex; 2 ) childhood nutritional status indexed by BMIZ at ages 4–6, 9–11, and 11–13 y, standardized using WHO norms. Potential mediators that were associated with SQ-LNS or aPDSZ at P < 0.10 were included in causal mediation analyses using the mediation package in R . Section title: Results Educational score: 3.9166464805603027 Domain: biomedical Document type: Study Language: en Out of 1320 mothers enrolled during the main trial, 1228 (93%) children were born live. A total of 1217 children were eligible to participate in the follow-up study at 9–11 y; 966 children participated in the pubertal development assessment including 635 in the non-LNS group and 331 in the SQ-LNS group. At 11–13 y, 919 children participated in the pubertal development assessment including 608 in the non-LNS group and 311 in the SQ-LNS group . The 966 and 919 included in the analysis were similar to the 354 and 401 enrolled in the main trial, respectively, but lost to follow-up regarding most background characteristics, such as baseline maternal education, food security, and BMI ( Supplemental Table 1 ). FIGURE 1 Flowchart of child’s eligibility, enrollment and data collection. FIGURE 1 Section title: SQ-LNS and non-LNS group comparisons Educational score: 4.165552139282227 Domain: biomedical Document type: Study Language: en Sensitivity analysis showed no difference between IFA and MMN groups ( P > 0.10) at both 9–11-y and 11–13-y follow-up; hence, we proceeded to analyze by a 2-group comparison, SQ-LNS and non-LNS groups (IFA+MMN). Table 2 presents selected maternal and child characteristics. The 2 groups generally did not differ significantly in the 11 maternal baseline characteristics presented except for baseline household asset index z-score. At 9–11 y ( P = 0.019) and 11–13 y ( P = 0.019), the SQ-LNS group had lower asset index z-score than the non-LNS group. TABLE 2 Selected maternal and child characteristics at 9–11-y follow-up. TABLE 2 Variable SQ-LNS ( n = 331) Mean (SD) or % ( n /total) Non-LNS ( n = 635) Mean (SD) or % ( n /total) Maternal characteristics at baseline Age (y) 27.0 (5.5) 26.8 (5.4) Education (y) 7.6 (3.8) 7.7 (3.6) Married or cohabiting, % ( n / N ) 91.8 (304/331) 94.0 (596/634) Household asset index z-score 1 –0.07 (0.97) 0.09 (0.97) Household food secure, % ( n / N ) 60.3 (199/330) 56.98 (359/630) Household improved water source, % ( n / N ) 99.1 (328/331) 98.1 (621/633) Household toilet facility, % ( n / N ) 97.6 (322/330) 97.6 (618/633) Height (cm) 159.1 (5.4) 158.8 (5.9) Prepregnancy BMI 2 (kg/m 2 ) 24.9 (4.5) 24.3 (4.4) Hemoglobin concentration (g/L) 111.5 (11.2) 111.4 (12.6) Primiparous, % ( n / N ) 33.7 (102/303) 31.7 (201/635) Child characteristics Dry season 3 , % ( n / N ) 50.5 (167/331) 48.9 (310/634) First born, % ( n / N ) 30.8 (102/331) 31.7 (201/634) Females, % ( n / N ) 51.7 (171/331) 51.7 (328/634) Child age at 4–6-y follow-up (y) 4.9 (0.6) 4.9 (0.5) Child age at 9–11-y follow-up (y) 9.9 (0.5) 9.9 (0.5) Birth weight for gestational age z-score –0.41 (0.97) –0.61 (0.95) Child BMIZ at 4–6 (y) –0.55 (0.81) –0.58 (0.81) Child BMIZ at 9–11 (y) –0.43 (1.18) –0.50 (1.16) PDS score 7.5 (1.1) 7.5 (1.1) Abbreviations: non-LNS, iron and folic acid + multiple micronutrient groups; PDS, Petersen Pubertal Development Scale; SQ-LNS, small-quantity lipid-based nutrient supplement. 1 Proxy indicator for household socioeconomic status constructed for each household based on ownership of a set of assets (radio, television, etc.), lighting source, drinking water supply, sanitation facilities, and flooring materials. Household ownership of this set of assets is combined into an index (with a mean of 0 and SD of 1) using principal components analysis. Higher value represents higher socioeconomic status. 2 Estimated prepregnancy BMI was calculated from estimated prepregnancy weight (based on polynomial regression with gestational age, gestational age squared, and gestational age cubed as predictors) and height at enrollment. 3 Born during the dry season. Section title: Effect of SQ-LNS on pubertal status Educational score: 4.0820441246032715 Domain: biomedical Document type: Study Language: en At 9–11 y, SQ-LNS (mean ± SD) did not impact pubertal status in the minimally adjusted (0.01 ± 0.95 compared with non-LNS: −0.01 ± 0.98, P = 0.748) or fully adjusted [mean difference (SE): 0.00 (0.06), P = 0.958] models. At 11–13 y, the SQ-LNS group was marginally more advanced in the minimally adjusted model (mean ± SD = 0.07 ± 1.04 compared with non-LNS: –0.04 ± 0.98, P = 0.078), and the group difference was significant in the fully adjusted model [mean difference (SE): 0.13 (0.07), P = 0.049]. Section title: SQ-LNS effect modifiers Educational score: 4.025932312011719 Domain: biomedical Document type: Study Language: en At 9–11 y of age, sex and household asset index z-score did not modify the effect of SQ-LNS on pubertal development ( P -interaction > 0.10). At 11–13 y of age, the effect of SQ-LNS on pubertal stage differed by sex and household asset index z-score . More advanced pubertal stage was observed in the SQ-LNS compared with non-LNS group among females (mean difference = 0.30 SD; 95% CI: 0.08, 0.52; P = 0.007) but not among males ( P = 0.167). More advanced pubertal stage was found for SQ-LNS compared with non-LNS groups in the first asset tertile (mean difference = 0.36 SD; 95% CI: 0.13, 0.60; P = 0.002) but not in the second tertile ( P = 0.436) or highest asset tertile ( P = 0.332) subgroups of household asset index z-score. Birth order did not modify the impact of SQ-LNS on pubertal stage at either age ( P -interaction > 0.10). FIGURE 2 SQ-LNS effect modification by sex at 11–13-y follow-up. aPDSZ, age-adjusted pubertal development scale z-score; non-LNS, iron and folic acid + multiple micronutrient groups; SQ-LNS, small-quantity lipid-based nutrient supplement. FIGURE 2 FIGURE 3 SQ-LNS effect modification by asset index z-score by tertile groups at 11–13-y follow-up. aPDSZ, age-adjusted pubertal development scale z-score; non-LNS, iron and folic acid + multiple micronutrient groups; SQ-LNS, small-quantity lipid-based nutrient supplement. FIGURE 3 Section title: SQ-LNS effect mediators at 11–13 y Educational score: 4.090217590332031 Domain: biomedical Document type: Study Language: en Mediation analysis showed that SQ-LNS impacted aPDSZ partially through birth weight for gestational age z-score (total effect = 0.12 SD, P = 0.074; direct effect = 0.11 SD, P = 0.098; indirect effect = 0.01 SD, P = 0.096; proportion mediated = 7%, P = 0.150). Child BMIZ at 4–6, 9–11, and 11–13 y were not associated with SQ-LNS intervention group ( P > 0.10) and thus were not found to be mediators. Section title: Discussion Educational score: 4.035541534423828 Domain: biomedical Document type: Study Language: en To our knowledge, this is the first RCT to investigate the impact of early life SQ-LNS during the first 1000 d of life on pubertal development. We found that adolescents who received SQ-LNS from 6 to 18 mo of age after maternal SQ-LNS consumption during pregnancy and 6 mo postpartum had greater mean aPDSZ at 11–13 y than those in the non-LNS group who received no direct supplementation after maternal IFA or MMN during pregnancy, and placebo or MMN during 6 mo postpartum. Section title: Discussion Educational score: 2.437363862991333 Domain: biomedical Document type: Study Language: en We did not observe an intervention effect on pubertal stage at 9–11 y. A lack of SQ-LNS effect on pubertal status at 9–11 y of age may be explained by relatively low reproductive maturity at 9–11 y when puberty has barely started, compared with increased reproductive maturity at 11–13 y when puberty is usually underway. Section title: Discussion Educational score: 4.21547269821167 Domain: biomedical Document type: Study Language: en Pubertal development is influenced by an interplay of hormones, central neurotransmitters, and environmental factors including nutrition, that induce the maturation of the HPG axis, although the mechanism of HPG axis reactivation is unknown . Thus, the activity of the endocrine axes may be altered during the first 1000 d of life by inadequate nutrient supplies to the fetus, decreased nutrient bioavailability, and restricted growth, possibly dysregulating the HPG axis and consequently impacting pubertal status. Because SQ-LNS is a nutrient-dense supplement, it may have contributed to the timely and appropriate regulation of the HPG axis during pregnancy and infancy, preparing the child for the reactivation of the HPG axis during puberty when the neural circuitry established during early life and infancy by gonadal steroids becomes functional again. Section title: Discussion Educational score: 4.23961067199707 Domain: biomedical Document type: Study Language: en Increase in weight is known to be associated with increases in leptin, insulin, IGF-1, and cortisol levels . Elevated insulin and IGF-1 levels promote growth in lean body mass, muscle mass, and fat mass, triggering a growth spurt . Leptin and IGF-1 also contribute to skeletal development by stimulating bone mineral accretion and bone maturation . Increased leptin also stimulates hormonal activity in the hypothalamus, pituitary, adrenals, and gonads, expediting pubertal development . However, it is unlikely that the observed group difference in mean aPDSZ at age 11–13 y was a result of group differences in obesity, as we found no intervention effect on BMI at 4–6, 9–11, or 11–13 y. Hence, BMI was not a mediator for pubertal development. Although BMI may not be an adequate proxy for fat mass, in this cohort BMI at 11–13 y was strongly correlated with triceps skinfold (rho = 0.80) and mid-upper arm circumference (rho = 0.94), which suggests that there were no intervention group differences in fat mass at 11–13 y, as was the case at 4–6 y and 9–11 y . Regarding effect modification, we found greater effects of SQ-LNS on aPDSZ among females and among adolescents in households with lower asset index z-scores. This agrees with previous findings indicating that the effect of SQ-LNS on social-emotional difficulties at 4–6 y was greater among children from disadvantaged homes , and the effect on height at 9–11 y was greater among females . During infant and child development, males and females show differences in their responses to hormonal changes . Furthermore, reactivation of the HPG axis during adrenarche and gonadarche begins earlier in girls than in boys . Therefore, females may have had greater potential to respond to early life SQ-LNS with regard to pubertal development at this age, compared with males. Because males typically exhibit later pubertal development than females , we may see an effect of SQ-LNS on this outcome among males at older ages, that is, >13 y. Regarding significant effect modification in lower socioeconomic households, it is possible that children with lower asset index scores with higher risk of malnutrition and poor cognitive functions tended to respond better to SQ-LNS compared with children from average and higher socioeconomic households. This hypothesis is supported by a prior individual participant meta-analysis wherein greater effects of SQ-LNS was found on language, motor, and executive function among children in lower socioeconomic households. We did not find birth order to be a significant modifier of SQ-LNS impact on pubertal status in this study, even though effects of SQ-LNS on stunting and underweight were greater in later-born than first-born children in individual participant data meta-analyses . Section title: Discussion Educational score: 4.10234260559082 Domain: biomedical Document type: Study Language: en Higher birth weight for gestational age z-score partially mediated the effect of SQ-LNS on aPDSZ. Previous studies have investigated birth and early life influences on puberty using anthropometric indices like birth weight as exposures . Most of these studies have focused on the Tanner stages or a few of the milestones on the PDS , and not the total PDS score. For example, in the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study , it was reported that children who weighed between 2500 and <3000 g at birth were ∼7 mo younger at age at take-off of the pubertal growth spurt than children who weighed ≥3000 g. This appears to conflict with our findings showing that SQ-LNS impacts aPDSZ partially through higher birth weight for gestational age. However, it is difficult to compare our findings with those of the DONALD study as we assessed how birth weight for gestational age, not birth weight, is associated with pubertal development. In this trial, we found that maternal SQ-LNS increased birth weight compared with the IFA group and reduced the risk of SGA compared with the MMN group . Therefore, the mediation by birth weight for gestational age observed herein is plausible, although it explained only 7% of the total effect of SQ-LNS on aPDSZ. Section title: Study strengths and limitations Educational score: 4.117802619934082 Domain: biomedical Document type: Study Language: en Our study has several strengths to note. First, this was an RCT, and the SQ-LNS and the non-LNS groups at 9–13 y did not differ significantly in baseline characteristics except for household asset index z-score, suggesting that the intervention groups remained balanced over time. Second, we had large sample sizes with good retention rates at both the 9–11 y (79%) and 11–13 y (75%) follow-up. Third, we used the PDS (for assessing pubertal stage) that has shown high validity in previous research . There are some potential limitations, however. Because we did not assess pubertal development at 7 y, we may have missed cases of precocious puberty in our study cohort. Consequently, we are unable to determine whether the SQ-LNS induced earlier onset of pubertal development than the non-LNS group. Nevertheless, the results show no record of precocious puberty assessed by menarche among females by self-report, and the mean aPDSZ does not suggest an earlier onset of pubertal development. Another limitation is that participants included in these analyses differed significantly in maternal parity ( P < 0.05) compared with those lost to follow-up. However, it is unlikely that this led to bias in the results because parity was not associated with pubertal status. Section title: Conclusions and recommendations Educational score: 3.7857935428619385 Domain: biomedical Document type: Study Language: en Provision of SQ-LNS in this setting during the first 1000 d of life was associated with more advanced pubertal stage among females at 11–13 y, but not at 9–11 y. Because we did not observe more advanced puberty in the younger age group, the results suggest that the advancement of puberty at 11–13 y was not an adverse outcome. This finding provides additional evidence that SQ-LNS influences both physical and behavioral development. More research is needed to understand the potential impact of early life SQ-LNS exposure on pubertal development among males, and the consequences of more advanced pubertal development among females. Section title: Author contributions Educational score: 0.9485378265380859 Domain: other Document type: Other Language: en The authors’ responsibilities were as follows – HN, SAA, ELP, BMO, AM, PDH, AEG, KGD, BA: conceptualized and designed the follow-up study; HN, SAA, ELP, EA, HJB, MOM, XT: conducted the research; HN, CA: conducted the statistical analyses; HN: led the writing of the manuscript with critical review from AM, KGD, CA, SAA, BMO, PDH, AEG, HJB, LMDA, MOM, and FAL. HN: had primary responsibility for final content. Because of her death during the preparation of this manuscript co-author ELP was unable to read and approve the final manuscript; all other authors: read and approved the final manuscript. Section title: Conflict of interest Educational score: 0.8587543964385986 Domain: other Document type: Other Language: en The authors report no conflict of interest. Section title: Funding Educational score: 1.0566215515136719 Domain: other Document type: Other Language: en This publication is based on research funded by grants to the University of California, Davis , from the National Institutes of Health and the Bill & Melinda Gates Foundation . The funders did not play a role in the design or implementation of the study or interpretation of the data. The findings and conclusions contained within are those of the authors and do not necessarily reflect the positions or policies of the Bill & Melinda Gates Foundation. Section title: Data availability Educational score: 0.9156162142753601 Domain: biomedical Document type: Other Language: en Data (on de-identified individuals) described in the manuscript, code book, and analytic code will be made available upon request to researchers who provide a methodologically sound proposal and statistical analysis plan contingent on approval by the Principal Investigators. Proposals should be submitted to the corresponding author. | Study | biomedical | en | 0.999997 |
PMC11697769 | Section title: Introduction Educational score: 4.078562259674072 Domain: biomedical Document type: Study Language: en The prevalence of ulcerative colitis (UC) is higher in Western countries compared to India. Changing dietary habits and lifestyles are projected to make India one of the countries with the highest disease burden of UC in the world . About 20% to 30% of patients with UC require surgery at some point . Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the preferred surgical treatment for UC, offering disease-free bowel function, reducing the cancer risk without a permanent stoma, and lowering long-term costs. Nevertheless, IPAA is not free from complications that affect long-term outcomes. Reported early complications are pelvic sepsis, bleeding, and surgical site infection, among others. The long-term complications include pouchitis, pouch-anal anastomosis stricture, pouch vaginal fistulae, and fecal incontinence. Many studies have reported acceptable complication rates, good functional outcomes, and good quality of life (QoL) after IPAA for UC . Most of these studies are from Western countries. There are only a few studies from India on the outcomes of IPAA in UC patients . This study was conducted at a tertiary care referral center in north India to identify the early and late postoperative complications of IPAA for UC and the associated predictors. Section title: Materials and methods Educational score: 1.7058687210083008 Domain: biomedical Document type: Study Language: en Study cohort Section title: Materials and methods Educational score: 4.160853385925293 Domain: biomedical Document type: Study Language: en All patients with UC who underwent IPAA in the Department of Surgical Gastroenterology at Sanjay Gandhi Postgraduate Institute of Medical Sciences between 1995 and 2018 were included in this study. Ethical approval for this study was obtained from the Institutional Bioethics Committee . Information about demographics, clinical parameters, operative details, and early and late postoperative complications were retrieved from a prospectively maintained hospital-based electronic database. Patients undergoing IPAA with diagnoses other than UC, Crohn’s disease, indeterminate colitis, or familial adenomatous polyposis were excluded. The extent of the disease was classified as ulcerative proctitis (E1), left-sided UC (E2), or pancolitis (E3) according to the Montreal Classification . The indications were recorded as elective indications, which comprised failed medical therapy (steroid-refractory UC, steroid-dependent UC), dysplasia, and malignancy. Emergent indications were acute complications such as toxic megacolon, perforation, and acute severe ulcerative colitis (ASUC). ASUC was defined using the Truelove and Wits criteria . The early complications were defined as complications within 30 days following IPAA. Early complications were graded according to the Clavien-Dindo classification . Pelvic sepsis was defined as “Any infective process in the peri pouch area, detected during the investigation of clinical symptoms. This includes all abscess formations associated with or without anastomotic leak or purulent drain output.” Late complications were those that occurred during the follow-up period before or after stoma closure. Late complications included small bowel obstruction, pouchitis (diagnosed endoscopically and/or by histopathology), abscess, anastomotic stricture, and pouch failure. The anastomotic stricture was defined as a clinically significant stricture that requires endoscopic or surgical dilation. Pouch failure was defined as the need to construct a permanent ileostomy with or without excision of the ileal pouch . A subjective scoring system on a scale from 0 to 10 was employed to evaluate patient satisfaction following surgery. Patients with a score of 9-10 were classified as very satisfied, those with a score of 6-8 as satisfied, and those with a score below or equal to 5 as poorly satisfied with surgery. Section title: Materials and methods Educational score: 2.2399449348449707 Domain: biomedical Document type: Other Language: fr Surgical technique Section title: Materials and methods Educational score: 3.9721007347106934 Domain: biomedical Document type: Study Language: en All patients were referred to surgery by a medical gastroenterologist after initial medical management with steroids, immunosuppressants, and biologics. Most patients were tapered off steroids before pouch construction. The two-stage procedure was defined as a proctocolectomy with the creation of the IPAA and covering loop ileostomy as the first stage, followed by the ileostomy closure. The three-stage procedure involves a subtotal colectomy with end ileostomy and distal mucosal fistulae creation during the first stage, followed by restorative proctocolectomy with IPAA and covering loop ileostomy, and, finally, ileostomy closure. The IPAA was performed either by the stapled or handsewn technique. All IPAA procedures were performed using the open technique. Section title: Materials and methods Educational score: 1.4600969552993774 Domain: biomedical Document type: Other Language: en Statistical analysis Section title: Materials and methods Educational score: 3.970724105834961 Domain: biomedical Document type: Study Language: en SPSS Statistics for Windows, Version 26.0 (IBM Corp., Armonk, NY, USA) was used for statistical analyses. Continuous variables are presented as mean and standard deviation (SD) or median (interquartile range (IQR)) depending upon normality status, while categorical variables are reported as raw values with percentages. Univariate analysis was performed using Pearson’s chi-square and Fisher’s exact tests. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using univariate logistic regression analysis to assess the relationship between the outcome and potential influencing factors. Variables with a p-value <0.05 in the univariate analysis were selected for multivariate analysis. Statistical significance was set at p-values <0.05. Risk factors for early complications were analyzed using univariate analysis. Various late complications such as pouchitis, anastomotic stricture, and pouch vaginal fistulae were separately analyzed using univariate analysis. Section title: Results Educational score: 3.8746449947357178 Domain: biomedical Document type: Study Language: en A total of 101 patients underwent IPAA for UC. The median age of the patients was 32 years (range = 14-67 years; IQR = 26-44 years). The median preoperative disease duration was 48 months (range = 1.0-260.0 months; IQR = 23.3-118.8 months). The median follow-up period was 64 months (range = 6.0-273.0 months; IQR = 35.5-136.0 months). The median length of hospital stay after IPAA was 12 days (IQR = 9-18 days). The demographic and clinical characteristics of patients are described in Table 1 . Section title: Results Educational score: 1.9464322328567505 Domain: biomedical Document type: Other Language: en Indication of surgery and surgical procedure Section title: Results Educational score: 4.061967849731445 Domain: biomedical Document type: Study Language: en The indications and types of surgery are described in Table 1 . A three-staged procedure was performed in 57 (56.4%) patients, while a two-staged procedure was performed in 44 (43.6%) patients. Most patients who underwent the three-stage procedure were steroid-refractory (n = 29, 50.8%) or had acute emergencies (n = 15, 26.3%). The two-stage procedure was primarily performed for steroid-dependent UC (n = 30, 68.1%). J-pouch was formed in 91 (90.1%)patients, while a W-pouch was formed in 10 (9.9%) patients. We performed a subgroup analysis to examine the complications rate between the J-pouch and W-pouch and could not find any significant difference. Most patients underwent IPAA using a double stapling technique (n = 74, 73.2%), while hand-sewn anastomosis was performed in 27 (26.7%) patients. A diverting loop ileostomy was performed for all patients following pouch-anal anastomosis. Three patients underwent a laparoscopic first-stage procedure (subtotal colectomy). The analysis revealed that in the initial five years, the number of pouches was high and decreased afterward, but it remained in a similar range from 2009 onward. The year-wise trend is shown in Figure 1 . Section title: Results Educational score: 2.0887138843536377 Domain: biomedical Document type: Other Language: en Early postoperative complications after IPAA Section title: Results Educational score: 4.037515640258789 Domain: biomedical Document type: Study Language: en In total, 72 (71.3%) patients experienced early postoperative complications (Table 2 ). The majority had Clavien-Dindo grade 1 (n = 27, 26.7%) and grade 2 morbidities (n = 24, 23.7%). Grade 3 and 4 morbidities were encountered in 17 (16.8%) and 3 (2.9%) patients, respectively. The most common complication was pelvic sepsis, observed in 26 (25.7%) patients. Of the 26 patients with pelvic sepsis, 15 had collections in the peri-pouch area, five had demonstrable pouch leaks, and six patients had purulent drain output. Of the 26 patients, seven required percutaneous drainage of collections, three required re-exploration, and the remainder were managed conservatively. Unfortunately, one patient died after IPAA in the immediate postoperative period due to anastomosis leak and sepsis. Overall, 10 (9.9%) patients required re-exploration in the early postoperative period for missed enterotomy (five cases), pelvic sepsis (three cases), and bleeding (two cases). Various risk factors analyzed to see their association with early complications are shown in Table 3 . None of the factors were significantly associated with early complications on univariate analysis. Section title: Results Educational score: 2.142502546310425 Domain: biomedical Document type: Other Language: en Late postoperative complications after IPAA Section title: Results Educational score: 3.8668978214263916 Domain: biomedical Document type: Study Language: en Late complications were observed in 59 (58.4%) patients. The late complications were as follows: pouchitis (n = 37, 36.6%), anastomotic stricture (n = 27, 26.7%), pouch-vaginal fistula (n = 11, 10.9%), pouch-perianal fistulae (n = 3, 2.9%), small bowel obstruction requiring re-exploration (n = 17, 16.83%), incisional hernia (n = 6, 5.9%), impotence (n = 1, 0.9%), and urinary retention requiring clean intermittent self-catheterization (n = 2, 1.9%). We analyzed various long-term complications separately, as outlined below. Section title: Results Educational score: 1.7864538431167603 Domain: biomedical Document type: Other Language: de Pouchitis Section title: Results Educational score: 3.524597406387329 Domain: biomedical Document type: Study Language: en Table 4 highlights the risk factors analyzed to assess their association with pouchitis. On univariate analysis, none were found to be significant in our study. Of the 37 patients with pouchitis, 34 responded to conservative management, such as oral antibiotics, hydrocortisone enema, and mesalamine suppositories. Three patients required pouch excision. Section title: Results Educational score: 2.3440778255462646 Domain: biomedical Document type: Other Language: en Pouch-Anal Anastomotic Stricture Section title: Results Educational score: 4.129735946655273 Domain: biomedical Document type: Study Language: en Of the 27 patients with anastomotic stricture, 19 (70.4%) had stapled anastomosis, and eight (29.6%) had hand-sewn anastomosis. The various risk factors analyzed to assess their association with anastomotic stricture are depicted in Table 4 . The presence of pelvic sepsis was significantly associated with the development of anastomotic stricture (OR = 2.704, 95% CI = 1.041-7.022, p = 0.041). All patients were subjected to a graded dilatation program. Overall, 24 (88.8%) patients underwent successful dilatation by endoscopic or surgical methods. The average number of dilation sessions in the present study was four. Three patients had unsuccessful dilatation; one of them required pouch excision due to severe pouchitis and coexisting pouch-vaginal fistulae. Two other patients were still living with a stoma at the time this study was completed. Section title: Results Educational score: 1.9937187433242798 Domain: biomedical Document type: Other Language: de Pouch-Vaginal Fistulae Section title: Results Educational score: 4.131045341491699 Domain: biomedical Document type: Study Language: en In total, 11 (10.9%) patients developed a pouch-vaginal fistula during the follow-up. While in five patients it was reported before the stoma closure, six patients found it after stoma closure. The various risk factors analyzed to assess their association with pouch-vaginal fistula are depicted in Table 4 . Hand-sewn anastomosis was the only factor significantly associated with the development of pouch-vaginal fistula in univariate analysis (OR = 3.943, 95% CI = 1.093-14.229, p = 0.036). Four of these patients required surgical repair, while two patients were managed with diversion ileostomy followed by restoration of continuity. One patient later had recurrent pouch-vaginal fistulae with severe pouchitis, leading to pouch excision. Two patients are still living with a stoma. Section title: Results Educational score: 1.679233193397522 Domain: biomedical Document type: Other Language: de Pouch Failure Section title: Results Educational score: 3.7820260524749756 Domain: biomedical Document type: Study Language: en In the long term, 11 (10.9%) patients suffered from pouch failure. Various causes of pouch failure included pouchitis (three patients), pouch-vaginal fistulae (three patients), pouch peri-anal fistulae (two patients), anastomotic stricture (two patients), and fecal incontinence (one patient). Three patients had their pouches excised with end ileostomy. In one patient, the pouch-anal anastomosis was dismantled, and the end of the pouch was made into a stoma. In seven patients, the stoma could not be reversed. Section title: Results Educational score: 1.6591532230377197 Domain: biomedical Document type: Other Language: en Long-term outcomes Section title: Results Educational score: 3.92345929145813 Domain: biomedical Document type: Study Language: en Follow-up data were collected from outpatient visit records, personal interviews, and telephone conversations. On analyzing the long-term outcomes, the average stool frequency was 6.18 ± 1.87/day. Daytime frequency was 4.05 ± 1.27/day, and nighttime stool frequency was 2.05 ± 2/day. Of the study population, patient satisfaction could only be assessed in 65 (64.3%) patients, who were contacted either in the outpatient department or via direct telephone conversation. Using a subjective scoring system, they were asked to rate their satisfaction with the surgery after IPAA on a scale of 0-10. Overall, 49 (75.3%) patients were either very satisfied or satisfied with the IPAA. Common reasons for dissatisfaction in the remaining patients were recurrent abdominal pain, increased stool frequency, and nocturnal incontinence. Section title: Discussion Educational score: 4.058394908905029 Domain: biomedical Document type: Study Language: en Despite the emergence of biologics and improved medical management, IPAA remains the surgical treatment of choice for UC when surgery is warranted. IPAA offers a one-time solution for UC, potentially providing significant relief for this vulnerable patient population. The demographic parameters in our study were similar to those reported in other studies. The median age at the time of surgery was 32 years, similar to Pal et al. from India . Of the study population, 16 (15.8%) patients had extraintestinal manifestations, but none presented with primary sclerosing cholangitis (PSC). Previous studies from Western countries have demonstrated that the prevalence of UC with PSC ranged from 13.3% to 21.8%, whereas it is uncommon in India . Studies by Kedia et al. and Singh et al. from India reported lower frequencies of PSC at 0.40% and 0.39%, respectively. Section title: Discussion Educational score: 4.1602020263671875 Domain: biomedical Document type: Study Language: en In the present study, medically refractory UC was the most common indication for surgery, accounting for 81.1% of cases. Similarly, in studies by Lim et al. and Zittan et al. , medically refractory UC was also the primary indication for surgery, comprising 83% and 74.9% of study populations, respectively. The initial first five-year higher number of patients reflects increased referral and non-availability of medical treatment for better control and remission such as biologicals, antimetabolites, and immunosuppressants. In our study, the majority of patients underwent three-staged procedures. In the study conducted by Zittan et al. , 37.6% of patients underwent three-stage procedure, 31.3% underwent a modified two-stage procedure, and 29.4% underwent two-stage procedure. The J-pouch was preferred in our study, although 10 patients had a W-pouch performed in the first few years. The J-pouch is the preferred type of reconstruction in other studies as well, as it is technically easier and has widely acceptable functional outcomes. In their meta-analysis, Lovegrove et al. demonstrated similar outcomes for all three types of pouches. In the present study, 74 (73.2%) patients underwent stapled anastomosis, while the remainder underwent hand-sewn anastomosis. Similarly, in a study conducted at the Cleveland Clinic, 87% of patients received stapled anastomosis, while 13% underwent hand-sewn anastomosis . In this study, there were no significant differences in long-term outcomes between stapled and hand-sewn anastomosis, except for pouch-vaginal fistula, which was more commonly associated with hand-sewn anastomosis than with stapled anastomosis. Section title: Discussion Educational score: 4.1548357009887695 Domain: biomedical Document type: Study Language: en In the largest study (n = 2,959) by Fazio et al. , the mortality rate in the perioperative period (<30 days) was 0.1%. However, in the present study, it was 0.9%, which seems higher and may reflect the small sample size. In the present study, 72 (71.8%) patients experienced early morbidity. The early morbidity rate in various studies ranged from 20% to 50% (Table 5 ). Although we observed a higher rate of overall early complications, only 21% were Clavien-Dindo grades 3 and 4, while the remaining 51% were Clavien-Dindo grades 1 and 2 complications. McCombie et al. observed grade 3-5 complications in 7.4% of patients. In the present study, a missed enterotomy was the most common cause of re-exploration (n = 5, 4.9%). In contrast, in the series by Kampka et al. , the most common reason for reoperation was an intra-abdominal/pelvic abscess (n = 6, 42.9%). Unlike in Western studies, the majority of patients with pelvic sepsis did not require re-exploration and were managed with percutaneous drainage. Section title: Discussion Educational score: 4.084307670593262 Domain: biomedical Document type: Study Language: en Despite the increased morbidity, the mortality rate was low and comparable with the published series. Our study did not find any significant factors associated with developing early complications. In contrast, various studies have reported that older age and preoperative steroid use are linked to the development of early complications . An increased rate of early complications in our study can be multifactorial. Although all patients in our study were tapered off steroids before pouch construction, many studies indicate that steroids are a significant risk factor for early complications following IPAA. Another factor contributing to the increased rate of early complications in our study was the patients’ general status. Although serum albumin levels were optimized before pouch construction, other factors, such as sarcopenia and American Society of Anesthesiologists grade, were not considered during the analysis. Many of our patients had compromised nutritional reserves that were not accurately reflected by serum albumin values. Additionally, although most patients underwent elective procedures, many can be accurately considered semi-elective procedures. Section title: Discussion Educational score: 4.122925758361816 Domain: biomedical Document type: Study Language: en Late complications were observed in 59 (58.4%) patients. Comparisons of late complications observed in different studies are outlined in Table 6 . On long-term follow-up, pouchitis was encountered in 37 (36.6%) patients. This rate is consistent with findings reported in other studies . Several studies have identified various factors linked to the development of pouchitis, such as extraintestinal manifestations, pancolitis, a history of PSC, and prior treatment with anti-tumor necrosis factor before colectomy . In the present study, we found no significant risk factors associated with pouchitis on univariate analysis. Only three (2.97%) patients required pouch excision due to severe pouchitis and associated fistulae, similar to the findings published in a previous study . Section title: Discussion Educational score: 4.08905029296875 Domain: biomedical Document type: Study Language: en The rate of anastomotic stricture reported in various studies ranges from 2% to 38% . In the present study, 27 (26.73%) patients developed anastomotic stricture. In our research, pelvic sepsis was significantly associated with anastomotic stricture, consistent with the findings of Lewis et al. . Other studies have demonstrated an association between female gender, pelvic sepsis, and hand-sewn anastomosis with the development of anastomotic stricture . Most of our patients responded to endoscopic or surgical dilation, with only three patients experiencing treatment failure. Similar results were observed in other studies, demonstrating a good response of anastomotic strictures to dilation . Our results indicate that most anastomotic strictures, which are typically non-fibrotic, can be successfully treated with dilation programs. Section title: Discussion Educational score: 4.081185817718506 Domain: biomedical Document type: Study Language: en The overall risk of pouch-vaginal fistula following IPAA ranges from 4% to 16%. Pouch failure is observed in 21% to 30% of patients with pouch-vaginal fistula . It is challenging to manage and is an essential factor leading to pouch failure . In the present study, 11 (10.8%) patients had pouch-vaginal fistulae. In the present study, hand-sewn anastomosis was found to be a risk factor for pouch-vaginal fistula although the CI was wide. Mallick et al. found that pouch-vaginal fistulas are also most common in patients with a history of pelvic sepsis. In the present study, 9 out of 11 patients (75%) with pouch-vaginal fistulas required some form of intervention, either repair or stoma creation, similar to findings reported in the literature . Section title: Discussion Educational score: 2.1228840351104736 Domain: biomedical Document type: Study Language: en While multivariate analysis can offer valuable insights into the relationships between multiple variables for the analysis of various early and late complications, we decided against using it in our study. This is due to the limited sample size and the lack of significant factors identified in the univariate analysis. Section title: Discussion Educational score: 4.1348466873168945 Domain: biomedical Document type: Study Language: en The present study showed pouch failure in 11 (10.9%) patients. The incidence of pouch failure was reported as 5.1% by the Cleveland Clinic, 7.7% by the UK Pouch Study Group, and 5.9% by Chapman et al. . Heuthorst et al. showed that pouch failure was significantly correlated with fistulae and pelvic sepsis. Similar results were also observed in our study, with all patients with pouch failure having pelvic sepsis in the immediate postoperative period, and 6 out of 11 patients had pouch-related fistulae. The average stool frequency was 6.18 ± 1.87/day, Daytime frequency was 4.05 ± 1.27/day, and nighttime stool frequency was 2.05 ± 2/day. In a study conducted at Cleveland Clinic, average daytime and nighttime frequencies were 5.06 ± 1.8 and 1.36 ± 1.3, similar to our results . In a study conducted in India by Rao et al. , the mean stool frequency was 7.2 stools per 24 hours. In Another study by Raviram et al. from India, the median stool frequency was 7 per 24 hours. Due to the study’s retrospective design, we devised a subjective scoring system ranging from 0 to 10 to assess satisfaction after IPAA. In our study, 75% of patients were satisfied or very satisfied after surgery. Similarly, in a study by Rao et al. , 85% of patients reported being very satisfied with the procedure. In another study conducted in India, Somashekar et al. reported a mean stool frequency of 7, with 84% of patients expressing satisfaction with the surgery. Section title: Discussion Educational score: 3.915026903152466 Domain: biomedical Document type: Study Language: en Our study has some limitations. First, its retrospective design results in bias and misclassification as many follow-up data were extracted from follow-up records. Second, the number of patients included in our study was smaller compared to the Western series. Third, the study period spanned over 30 years, during which changes in patient management, surgical techniques, and perioperative care could have influenced the results. Despite these limitations, this is the largest study conducted in India to date that describes various complications and analyzes risk factors associated with IPAA in patients with UC. Section title: Conclusions Educational score: 4.08250617980957 Domain: biomedical Document type: Study Language: en In our study, both early and late complications were significantly high. The majority of early complications were minor except pelvic sepsis. Major late complications were pouchitis, strictures, pouch-vaginal fistulae, and pouch failure. No factors were found to be significantly associated with early complications. However, pelvic sepsis and hand-sewn anastomosis were significant predictive factors for the development of anastomotic stricture and pouch-vaginal fistulae, among late complications. By keeping the predictive factors in mind, surgeons may anticipate complications, which may help in performing prompt and judicious interventions to deal with these complications to improve the outcome. These factors may also help to take preventive measures during surgery to minimize morbidity. The result of our study will guide surgeons to be aware of possible complications of IPAA in UC and how to minimize and manage them. | Study | biomedical | en | 0.999996 |
PMC11697778 | Section title: Introduction Educational score: 4.132011413574219 Domain: biomedical Document type: Study Language: en Autologous “free flap” breast reconstruction (ABR) is a highly regarded option for women undergoing breast cancer surgery due to its natural feel, aesthetic appeal, and ability to maintain sensory function. The positive psychosocial benefits of this approach have been extensively acknowledged, making it a valuable option for a multitude of patients. 1 , 2 In addition, ABR is a durable option that can endure the effects of aging, without the risk of implant-related complications or necessity for prothesis replacements. 3 ABR procedures are now common in healthcare clinics worldwide, with various surgical methods described in the literature. 2 , 4 , 5 Ongoing research into new imaging modalities and recovery optimization techniques aims to enhance the efficacy of these procedures. 6 , 7 However, there is no centralized international consensus on ABR preparation and perioperative care, resulting in a dependence on nonstandardized national or intramural guidelines. Therefore, this study aimed to gain insight into the global practice patterns of ABR experts worldwide, focusing on flap choice, imaging modalities, monitoring devices, perioperative care, and additional surgical possibilities such as direct contralateral symmetrical reduction and surgical lymphedema treatment. The purpose of this study is to provide novice and experienced plastic surgeons with a global perspective on ABR practices, based on the collective insights from surgeons worldwide. This can serve as a reference point when implementing ABR in their hospitals or clinics, encouraging critical assessment, informed decision-making, and potential refinements of their local ABR guidelines. Section title: Method Educational score: 4.015211582183838 Domain: biomedical Document type: Study Language: en This research is a descriptive quantitative study conducted by the Department of Plastic Surgery at Radboud University Nijmegen in the Netherlands. The aim was to gather information worldwide using a questionnaire consisting of 42 multiple-choice and 10 open-ended questions. The survey covered topics such as donor site selection, surgical approaches, imaging modalities, and perioperative care. Information about the participating surgeons’ details, practice settings, and experience were also collected. The survey questions are available in the appendix. The researchers extensively searched the PubMed and SciELO databases to identify plastic surgeons involved in articles related to ABR. A total of 280 subjects and 39 international societies of plastic and reconstructive surgery were contacted by mail for inclusion in this study. They were asked to complete an online survey using the LimeSurvey application (version 2.06+). Nonresponders were sent reminder emails 2 and 4 weeks after the initial email. If no response was received, a phone call was made to inquire about their interest in participating. This research targeted plastic surgeons who are directly involved with ABR procedures and those affiliated with healthcare centers where these procedures are performed. Section title: Method Educational score: 4.05478048324585 Domain: biomedical Document type: Study Language: en The objective of this study was to collect data through an online questionnaire with subquestions directed to the respondents on the previous answers, assisting in providing an individual-centered questionnaire. Consequently, different sample sizes were taken for carrying out the analyses on specific segments of the data. The data were coded anonymously to ensure confidentiality and the analysis was carried out using IBM SPSS Statistics 27. Moreover, frequency analysis and crosstabulation tests were used to assess the demographics and relationship between multiple variables. Further, the Chi-squared test of independence was employed to determine the relationships between the categorical variables in the study. Although all responses were reviewed and analyzed, we prioritized presenting only the results with sufficient response rates. Data with low response rates or incomplete answers were excluded from the final analysis when they did not contribute meaningfully to the overall findings. This selective approach allowed us to focus on presenting reliable and representative trends, ensuring a more robust and comprehensive overview of global practices in autologous breast reconstruction. Section title: Results Educational score: 2.1275322437286377 Domain: biomedical Document type: Study Language: en A total of 82 responses were received, with 71% (n=58) being completed questionnaires. The tailored design of the study enabled respondents to respond to only questions that were applicable to them, resulting in varied sample sizes across subsections. Out of all 82 respondents who completed the demographic subsection, 59% (n=48) practiced only in an academic setting, 25% (n=21) in a nonacademic setting, 10% (n=8) in private clinics, 4% (n=3) in a both academic and private settings, and 2% (n=2) in all three settings. Section title: Results Educational score: 1.4396406412124634 Domain: other Document type: Other Language: en Among these respondents, 33% (n=27) were from North America, 1% (n=1) from South America, 43% (n=35) from Europe, 19% (n=16) from Asia, and 4% (n=3) from Australia. Unfortunately, there were no respondents from Africa. Section title: Results Educational score: 2.2339975833892822 Domain: biomedical Document type: Study Language: en Among all the respondents, 74% (n=60) were microsurgeons performing ABR as principal surgeons and 75% (n=45) had less than 15 years of experience. Section title: Preoperative imaging Educational score: 3.4671707153320312 Domain: biomedical Document type: Study Language: en Data from 60 respondents were analyzed to understand the prevalence and preferences of imaging techniques used in the preoperative phase. Among these respondents, approximately 75% (n=44) used preoperative imaging routinely, with most of them preferring CTA (82%, n=36). No association was observed between not using imaging and the unavailability of imaging modalities at the respondents’ healthcare centers. Among the 16 respondents who reported not using preoperative imaging, the majority (80%, n=12) stated that imaging would not make any difference in the outcomes. Section title: Preoperative imaging Educational score: 3.3269877433776855 Domain: biomedical Document type: Study Language: en Among the respondents who used imaging modalities preoperatively, 52% (n=23) used a combination of modalities. Sixty-one percent (n=14) used CTA with a handheld Doppler as their preferred combination, primarily to confirm the location of perforators and reduce intraoperative identification time. The use of a single imaging modality and a combination of modalities were evenly distributed across all healthcare centers: academic, nonacademic, and private clinics. Section title: Preventive actions Educational score: 2.9287407398223877 Domain: biomedical Document type: Study Language: en In the preoperative phase, insights were gathered from 77 respondents regarding preventive measures for perfusion problems. A substantial minority (41%, n=31) reported taking proactive preventive actions. Twenty-three respondents (74%, n=23) used low molecular weight heparin (LMWH), whereas 7 (23%, n=7) used mono-antiplatelet therapy. Section title: Donor site Educational score: 4.157702922821045 Domain: biomedical Document type: Study Language: en Regarding intraoperative planning for ABR, data from 60 respondents were analyzed. Most respondents preferred to use abdominal donor site flaps, with the DIEP flap being the most commonly used (85%, n=51), followed by the transverse rectus abdominis myocutaneous (TRAM) flap (13%, n=8), and superficial inferior epigastric artery (SIEA) flap (2%, n=1). Among the 51 respondents who indicated having an alternative option, the SIEA- and the transverse upper gracilis flap were the most commonly used second-choice flaps, each used by 22% (n=13) of the respondents, followed by the TRAM flap in 17% (n=10) of the cases ( Table 1 ). Table 1 Respondents’ preferential donor site and their second choice donor site preferences in case their first choice was unavailable/unsuitable. Table 1 Donor site Preferential donor site (%) (n=60) Second choice (%) (n=51) Deep Inferior Epigastric Pedicle Flap (DIEP) 85% (n=51) 7% (n=4) Transverse Rectus Myocutaneous Flap (TRAM) 13% (n=8) 23% (n=14) Superficial Inferior Epigastric Artery Flap (SIEA) 2% (n=1) 22% (n=13) Latissimus Dorsi Flap (LD) 0% 2% (n=1) Thoracodorsal Artery Perforator Flap (TDAP) 0% 2% (n=1) Superior Gluteal Artery Perforator Flap (SGAP) 0% 5% (n=3) Inferior Gluteal Artery Perforator Flap (IGAP) 0% 3% (n=2) Transverse Upper Gracilis Flap (TUG) 0% 22% (n=13) Profunda Artery Perforator Flap (PAP) 0% 7% (n=4) Section title: Recipient vessels Educational score: 3.5597894191741943 Domain: biomedical Document type: Study Language: en The internal mammary artery was the most commonly used recipient vessel (90%, n=54), followed by the thoracodorsal artery (82%, n=49) in case the internal mammary artery was unsuitable. Section title: Number of perforators Educational score: 2.3712310791015625 Domain: biomedical Document type: Study Language: en The distribution of perforators used was roughly even among the 51 respondents who preferentially used the DIEP flap: 47% (n=24) used one perforator and 51% (n=26) used two perforators. These preferences were consistent across academic, nonacademic, and private clinics. Section title: Intraoperative imaging Educational score: 3.9217922687530518 Domain: biomedical Document type: Study Language: en Data from 58 respondents were analyzed to examine the utilization trends of intraoperative imaging and their confidence levels in performing ABR. Approximately one-third (33%, n=19) used imaging to locate perforator vessels during surgery, with the majority (89%, n=17) using handheld Doppler. During ABR, 60% (n=35) of the respondents reported always feeling confident, while the remaining respondents indicated usually feeling confident during free flap harvesting. Notably, all respondents who reported feeling confident without intraoperative imaging usually used an imaging modality preoperatively. Section title: Intraoperative imaging Educational score: 3.396998167037964 Domain: biomedical Document type: Study Language: en The respondents also reported their confidence in flap harvesting without preoperative imaging. The confidence levels of the 43 respondents who completed the subsection on flap harvesting without preoperative imaging were analyzed and the majority reported moderate (28%, n=12) to very high (35%, n=15) levels of confidence. Respondents who reported always feeling confident in performing ABR used more frequent preoperative imaging (48%, n=28) than those who reported usually feeling confident (25%, n=15). However, no significant association was found between the confidence level during flap harvesting and preoperative imaging usage (p=0.21). The respondents’ confidence levels were self-estimated in this survey. Section title: Additional surgical possibilities Educational score: 3.9998698234558105 Domain: biomedical Document type: Study Language: en Data from 60 respondents were analyzed to identify the current intraoperative surgical methods in ABR surgeries. These procedures included contralateral symmetrical breast reduction, lymphedema treatment, and direct nipple reconstruction. Contralateral symmetrical breast reduction during initial ABR is not a standard procedure. One-third of the respondents (33%, n=20) never performed contralateral symmetrical breast reduction during the initial ABR, whereas approximately a quarter (23%, n=14) performed this in less than 25% of the cases. Approximately one-fifth (18%, n=11) always performed breast reduction in case of asymmetry. Furthermore, 8% (n=5) of the respondents performed it in more than 75% of the cases, 17% (n=8) in 25%-75% of the cases, and 3% (n=2) did so rarely or not at all. In academic and nonacademic settings, approximately half of the respondents performed contralateral reductions during the initial ABR, indicating a similar trend. Section title: Additional surgical possibilities Educational score: 2.111172914505005 Domain: biomedical Document type: Study Language: en A minority of respondents (16%, n=10) treated lymphedema during ABR using vascularized lymph node transplantation (VLNT). All of them were working in an academic setting. Section title: Additional surgical possibilities Educational score: 2.1881825923919678 Domain: biomedical Document type: Study Language: en As for direct nipple reconstruction, the vast majority never performed this during the initial ABR (88%, n=53). There was no difference in the frequency of this supplementary procedure among academic, nonacademic, and private clinics. Section title: Prophylactic actions Educational score: 3.618276357650757 Domain: biomedical Document type: Study Language: en The intraoperative preventive measures for perfusion issues were based on data from 77 respondents. Intraoperative preventive actions were reported by 43% (n=33) of the respondents. The most commonly reported actions included the application of warmth (42% n=14), followed by the administration of anticoagulant such as LMWHs (33%, n=11) and mono-antiplatelets (18%, n=6). Popular combinations included LMWH plus warmth application (18%, n=6) and LMWH plus mono-antiplatelet therapy (18%, n=6). Section title: Challenges and practice settings Educational score: 3.5673668384552 Domain: biomedical Document type: Study Language: en Intraoperative challenges were evaluated based on the data from the 58 respondents, highlighting the most challenging aspects of ABR. Respondents were asked to rate the challenges on a scale of 1 to 5, with 1 indicating “not a challenge” and 5 indicating “very challenging.” Among the 35 respondents who experienced challenges during ABR, achieving symmetry was rated as the most challenging, with a mean score of 2.8. Achieving proportional body dimensions in bilateral reconstructions was the second most challenging, with a mean score of 2.6, followed by donor site wound healing, which had a mean score of 2.4 . Figure 1 Level of reported difficulty in ABR in academic, nonacademic, and private clinics. The difficulty level is rated on a scale of 1 (not a challenge) to 5 (very challenging). Figure 1 Section title: Flap failure Educational score: 4.105347633361816 Domain: biomedical Document type: Study Language: en Flap failure and its management were analyzed based on the data from the 58 respondents, providing insights into the frequency and types of anastomotic revisions performed postoperatively. Among the 58 respondents, 79% (n=46) acknowledged experiencing postoperative flap failure to varying extents. In cases where anastomotic revisions were deemed necessary, 91% (n=42) of the respondents indicated the need to revise the venous anastomoses, while 76% (n=35) reported the need to revise the arterial anastomoses at various frequencies. The specific percentages and distribution of these revision frequencies are detailed in Table 2 . Table 2 Frequency with which venous or arterial anastomosis revisions were required when revision was deemed necessary. Table 2 Revision likelihood Venous revisions Arterial revisions Rarely (1%-5% of cases) 28 (61%) 31 (68%) Occasionally (6%-10% of cases) 7 (15%) 1 (2%) Sometimes (11%-20% of cases) 0 (0%) 1 (2%) Often (>20% of cases) 7 (15%) 2 (4%) Total respondents 42 (91%) 35 (76%) Section title: Flap failure Educational score: 3.6785941123962402 Domain: biomedical Document type: Study Language: en Notably, most respondents who experienced flap failure did not take preventive actions for perfusion problems preoperatively (60%, n=35) or intraoperatively (72%, n=42). However, no significant correlation was found between the incidence of flap failures and absence of preventive actions taken preoperatively (p=0.73) or intraoperatively (p=0.49). Section title: Preventive actions Educational score: 3.887089252471924 Domain: biomedical Document type: Study Language: en Postoperative preventive actions and their implications were assessed based on the data from 77 respondents. Among these respondents, 75% (n=58) reported taking postoperative preventive actions. Medicinal treatments were predominantly administered in the postoperative phase, with 67% (n=39) administering LMWHs and 28% (n=16) using mono-antiplatelet therapy. The most common combinations of preventive actions were LMWHs with warmth application (10%, n=6) or LMWHs with mono-antiplatelet therapy (10%, n=6). Section title: Flap viability assessment Educational score: 3.401022434234619 Domain: biomedical Document type: Study Language: en Flap viability assessment was analyzed postoperatively based on the data from 72 respondents, offering insights into the frequency, methods, and personnel involved in the assessments. Flap viability was primarily monitored by ward personnel such as nurses alone in 86% (n=62) of the cases, together with a plastic surgeon in 19% (n=14), and alongside a plastic surgeon and resident in 15% (n=11) of the cases. Section title: Flap viability assessment Educational score: 4.071839332580566 Domain: biomedical Document type: Study Language: en Monitoring was conducted hourly (67%, n=48) on the first day, every 2 h (49%, n=35) on the second day, and every 4 h (46%, n=33) on the third day after surgery. The viability of the flaps was assessed based on the following parameters: temperature (85%, n=61), color (97%, n=70), capillary refill (92%, n=66), and edema (53%, n=38). Most plastic surgeons (85%, n=61) used monitoring devices to assess flap perfusion. Handheld Doppler (74%, n=53) was the most commonly used device, followed by local SpO 2 sensors (14%, n=10), implantable Dopplers (11%, n=8), and temperature sensors (11%, n=8). Section title: Hospital stays Educational score: 2.1759684085845947 Domain: biomedical Document type: Study Language: en Data from 74 respondents were used to analyze the length of postoperative stay in the hospital. Sixty-eight percent (n=51) of the respondents discharge their patients within 5 days postoperatively . The average length of hospital stay was 5 days for academic hospitals and private clinics and 4 days for nonacademic hospitals. Figure 2 Duration of hospital stays for patients following autologous breast reconstruction in healthcare centers worldwide. Figure 2 Section title: Discussion Educational score: 2.6577610969543457 Domain: biomedical Document type: Study Language: en ABR is increasingly being considered as an option for women undergoing breast cancer surgery. This study assessed the current practices in ABR on a global scale. Despite the rising demand and technological advancements in ABR, the consensus on perioperative care remains elusive. Through a tailored survey approach, this research aimed to provide an overview of how ABR are performed worldwide. Section title: Discussion Educational score: 3.881132125854492 Domain: biomedical Document type: Review Language: en A preoperative vascular map assists in selecting the appropriate perforator. Most plastic surgeons use CTA imaging as it has been shown to be the most accurate and precise method for visualizing perforators. 8 Furthermore, recent studies have revealed that CTA imaging can also assess the suitability of flap tissue for mobilization. 9 However, for patients who need to minimize their exposure to radiation or contrast, alternative imaging techniques such as MRA and handheld Doppler are valuable alternatives. 10 Section title: Discussion Educational score: 4.054757595062256 Domain: biomedical Document type: Study Language: en In this study, most respondents (89%, n=17) used handheld Doppler alongside preoperative imaging to locate perforator vessels during surgery. The literature further identifies several real-time perforators imaging techniques, including duplex, fluorescence near-infrared angiography, and dynamic infrared thermography. Additionally, techniques such as image-guided stereotactic navigational systems and 3D-printed anatomical models are reported to enhance precision when paired with volumetric imaging. 6 Section title: Discussion Educational score: 3.9927735328674316 Domain: biomedical Document type: Study Language: en The reported usage rate of intraoperative imaging modalities was 33% (n=19), which was lower than initially anticipated. 10 This discrepancy could be due to certain complementary techniques, such as the handheld Doppler, which were described and categorized as imaging modalities. Although the handheld Doppler is frequently used as a complementary technique to identify perforator vessels and assess anastomosis patency intraoperatively, it is technically not an imaging modality. Consequently, the reported use of “complementary techniques” might be understated compared to their actual usage. Section title: Discussion Educational score: 4.046300888061523 Domain: biomedical Document type: Study Language: en Consistent with the findings of previous studies, this study's findings reaffirm that the abdomen remains the predominant donor site for microvascular ABR, with the DIEP flap often considered as the gold standard. 3 A secondary benefit of selecting the abdominal donor site is the more aesthetic abdominal contour observed postoperatively. 11 Notably, as with several studies, the choice of donor site remains a highly individualized decision, contingent on a patient's unique needs, circumstances, and body dimensions. Section title: Discussion Educational score: 4.01585054397583 Domain: biomedical Document type: Study Language: en Regarding intraoperative challenges, muscle preservation during ABR was reported as a significant challenge, ranking it as the fourth most challenging aspect. Despite proper soft tissue management, this remains a critical issue. 7 Although the literature claims limited donor site morbidity, clinically significant bulges or hernias are reported as complications of DIEP flap reconstructions. 12 A promising robotic approach to DIEP flap harvest has been described in the literature, aiming to minimize abdominal wall disruption and optimize muscle preservation. 7 Another major challenge in ABR is achieving proportional body dimensions and symmetry. Although the current techniques largely depend on the surgeon's judgment, a study by Hummelink et al. proposed a virtual flap planning method using 3D stereophotogrammetry and CTA, potentially assisting surgeons in accurately harvesting the correct flap volume. 5 Section title: Discussion Educational score: 4.036454200744629 Domain: biomedical Document type: Study Language: en Regarding preventive actions against perfusion problems occurring postoperatively, 67% (n=39) of the surgeons administered LWMHs whereas 28% (n=16) used mono-antiplatelet therapy intraoperatively; a combination of both was observed in 10% (n=6) of the cases. LMWH has been described in the literature as an essential thromboprophylactic measure during surgery. 13 Although LWMH is recommended, the use of a combination of LMWH and mono-antiplatelet therapy is debatable, especially for low-risk cardiovascular patients. Enajat et al., in their retrospective review, found no significant difference in the incidence of microvascular complications between patients who received both medications and those who received only LMWH perioperatively. 14 Moreover, considering the known risks and significantly higher incidence of hematoma in patients receiving both medications, they recommended discontinuing the administration of mono-antiplatelet therapy postoperatively. Section title: Discussion Educational score: 4.06667947769165 Domain: biomedical Document type: Study Language: en In cases of flap failure, venous anastomoses were revised more frequently (91%, n=42) than arterial anastomoses (76%, n=35), reflecting a higher likelihood of venous thrombosis over arterial occlusion as the cause of flap failure. Interestingly, a study conducted by Masoomi et al. revealed that venous thrombosis has a higher rate of successful treatment upon re-exploration compared to arterial occlusion. 15 Given the urgency of timely interventions, 85% (n=61) of plastic surgeons use devices for postoperative neo-mamma monitoring, predominantly the handheld Doppler (74%, n=53), followed by local SpO 2 sensors, implantable dopplers, and temperature sensors. With ongoing advancements, there is growing interest in innovative flap assessment methods. In recent literature, promising techniques such as near-infrared spectroscopy and implantable Doppler have been described for flap assessment, providing continuous objective physiological data on tissue perfusion. 16 , 17 Section title: Discussion Educational score: 4.021808624267578 Domain: biomedical Document type: Study Language: en Regarding supplementary surgical interventions, a minority of respondents reported performing intraoperative lymphedema treatment using VLNTs. The limited implementation of this procedure may be due to it primarily being performed in academic settings and the logistical challenge of the additional operation time required. Nevertheless, the incidence of lymphedema following breast cancer treatment is relatively high, ranging from 24% to 49% after mastectomy. 18 Research has shown that combining VLNT with DIEP flap breast reconstruction can significantly improve lymphedema-related quality of life rate. 19 Regarding this supplementary procedure, this study focused solely on whether lymphedema treatment was performed during initial surgery. A further in-depth analysis of lymphedema treatment was not conducted. Section title: Discussion Educational score: 3.4434406757354736 Domain: biomedical Document type: Study Language: en Postoperatively, patients typically stay hospitalized for an average of 5 days. Prior research, including the one by Frey et al., associate microsurgical ABR with longer operative times and extended hospital stays. 20 To address this, an enhanced recovery after surgery protocol has been introduced to optimize recovery of patients after DIEP flap reconstructions. 21 , 22 Section title: Discussion Educational score: 2.2817397117614746 Domain: biomedical Document type: Study Language: en In this study, 75% of the respondents had less than 15 years of experience as a surgeon. This suggests that the results represent the perspectives of relatively young and potentially recently trained group of surgeons. Furthermore, approximately three-quarters of the respondents were microsurgeons performing ABR procedures by themselves, indicating that the findings reflect current practices. Section title: Limitations Educational score: 3.065901517868042 Domain: biomedical Document type: Study Language: en To ensure data accuracy for each subsection, all individual question responses were considered for each subsection, regardless of the survey completion status. Although this approach improved the understanding across topics, it led to varying sample sizes across the data subsections. To provide clarity, the specific sample sizes have been explicitly stated for each subsection. Additionally, the customized design of this study enabled respondents to answer only the questions that were applicable to them, contributing to the variability in sample sizes. Cross-continental comparisons were hindered by limited samples from different continents. This uneven distribution of data across continents highlights where ABR research or practices are the most common and also suggests potential geographical biases in the dataset. Accuracy in calculating the response rate was compromised by emails sent to individual plastic surgeons and societies of unknown sizes. Consequently, a reliable response percentage could not be determined and is therefore not reported. Section title: Limitations Educational score: 2.6173882484436035 Domain: biomedical Document type: Study Language: en Lastly, relying solely on self-assessments by respondents may introduce recall bias, especially regarding confidence in performing ABR or flap failure incidence. However, this approach also captures real-world perceptions and experiences, adding authenticity to the findings. Section title: Conclusion Educational score: 3.872657060623169 Domain: biomedical Document type: Study Language: en This study provides valuable insights into the current practices of ABR worldwide, serving as a comprehensive overview for novice and experienced plastic surgeons. By broadening horizons beyond the local methodologies, it will aid in making well-informed decisions during the preparation and perioperative care of ABR, and underscores the potential areas for innovation in breast surgery. Although not a definitive guide, this study provides a state-of-the-art portrayal of how ABR is performed worldwide. Section title: Conflict of Interest Educational score: 0.9614296555519104 Domain: other Document type: Other Language: en The authors declare no conflicts of interest as this study received no financial support, and the study report was not influenced by personal relationships of the authors. | Study | biomedical | en | 0.999997 |
PMC11697783 | Section title: Introduction Educational score: 4.899975299835205 Domain: biomedical Document type: Study Language: en 3′-Phosphoadenosine 5′-Phosphosulfate (PAPS) is the universal sulfuryl donor. PAPS is synthesized by bifunctional PAPS synthase (PAPSS) that contains N-terminal APS kinase (APSK) and carboxy terminal ATP sulfurylase (ATPS) domains . First the carboxy terminal ATPS domain of hPAPSS1 (residues ∼220–623) condenses the sulfuryl group from inorganic sulfate on to adenylyl moiety of ATP to form Adenosine 5′-Phospho Sulfate (APS) and PPi. In the second step the 3′-hydroxyl of APS is phosphorylated by the amino terminal domain (residues ∼1–268) by APS kinase using ATP to form PAPS and ADP . In humans there are three isoforms referred to as hPAPSS1, hPAPSS2a, hPAPSS2b . hPAPSS1 and 2 are ∼77 % identical and the hPAPSS 2b differs from 2a by possessing an extra pentapeptide sequence GMALP . All three hPAPSS isoforms contain typical N-terminal APSK domain and C-terminal ATPS domain deduced by linear amino acid sequence that contains conserved ATP binding motifs . The exact regions that are necessary for APS-kinase and ATP sulfurylase domain is not clear for isoforms especially the 2a and 2b. However, previous study with hPAPSS1 indicated residues between 220 and 265 (referred to as linker sequence) is a must, for both APS kinase and ATP sulfurylase activities . ATPS is a alpha-beta ATP bond splitting enzyme in contrast to the most common beta-gamma bond cleaving kinases. On the other hand, APSK is a beta-gamma phosphoanhydride ATP bond splitting enzyme that has the P-loop with a typical Walker A motif (GxxGxxK) [ , , ]. The transfer of gamma-phosphoryl from ATP onto 3′-OH of APS is purported to require Mg 2 + that interacts with residues of the D 87 GD 89 N phosphotransferase motif. Mutation of both aspartic residues (D 87 ,D 89 ) abolished APSK activity without any drastic consequences for ATPS activity . Phosphoadenosine 5′-phosphosulfate (APS) binds to ATPS and APSK. In ATPS domain the APS is a product and for APSK it is a substrate. D 87 GD 89 N is absent in ATPS but present in APSK. Mutation of both aspartic residues (D 87 ,D 89 ) into alanine did not hamper the ATPS but abolished APSK activity . Section title: Introduction Educational score: 4.534107685089111 Domain: biomedical Document type: Study Language: en ATP sulfurylase lacks the GxxGxxK motif for ATP binding, instead it contains conserved H 425 NGH 428 residues coined here as Venk motif. Previously, site selected mutations of the H 425 and H 428 single mutant into alanine completely knocked out the ATPS activity . ATPS being a adenylyl-sulfotransferase, transfers sulfate group onto adenylyl moiety of ATP which then releases the products APS and PPi. The released PPi is hydrolyzed by ubiquitous pyrophosphatase into 2Pi. This drives the thermodynamically unfavorable ATPS reaction forward. In contrast most kinases (gamma-phosphoryl transferases) are beta-gamma bond splitting enzymes that binds ATP and drives the reactions thermodynamically in the forward direction . Whereas ATPS enzyme is unfavorable in the forward direction, is driven forward with the help of separate pyrophosphatase enzyme . Thus, PAPSS is the only bifunctional enzyme that we know of that uses ATP in two different manners. ATPS domain is a alpha-beta phosphoanhydride bond cleaving type and APSK is a beta-gamma phosphoanhydride bond cleaving activity domain. In this paper we report that the dual mutation of H 425 A-H 428 A makes the ATP binding nearly impossible with high energy required compared to wild type (WT). In addition, this is the first report to show the advantage of basic residue at position 426. In hPAPSS1, 2a and 2b the residue 426 is an asparagine (N). When N426 is mutated to K it improves the catalytic efficiency of hPAPSS1 by 3–4 folds. ATPS from various organisms Riftia symbiont , Saccharomyces cerevisiae , Penicillium Chrysogenum , Aquifix aeolicus , and Thermus thermophilus contained R instead of N in the HNGH region of hPAPSS . The in silico binding kinetics of N 426 –K mutant of hPAPSS1 exhibit much less energy than WT for ATP binding. In this paper we also report the kinetics of individual C-terminal domain (polypeptide 220–623) and N 426 –K mutant which are quite different and fascinating. Section title: Methods Educational score: 1.5197566747665405 Domain: biomedical Document type: Other Language: en Materials-For enzyme assays radioactive inorganic [ 35 S]SO 4 , and for DNA sequencing [α- 35 S]ATP were purchased from NEN Life Science Products. From the companies of Life Technologies, Inc. and Gene Probe Technology (Gaithersburg, MD).oligonucleotides were purchased. From U. S. Biochemical Corp. version-2 sequencing kit was obtained. Agarose was purchased from FMC BioProducts (Rockland, ME) Polyethyleneimine cellulose (PEI)-TLC plates were purchased from Merck. Site-directed mutagenesis kit was obtained from Stratagene (La Jolla, CA). x-ray film was purchased from Eastman Kodak Co. Section title: Site-selected mutagenesis Educational score: 4.238709449768066 Domain: biomedical Document type: Study Language: en The conserved motif (H 425 NGH 428 )) located in the COOH-terminal region of human PAPS synthase was used for site selected mutagenesis experiments. Amino acid substitutions were carried out corresponding to the H 425 NGH 428 sequence. Using the quik change mutagenesis kit from Strategene, mutations were performed by following instructions from the manufacturer. For example, oligonucleotides containing the respective base substitutions corresponding to the selected mutated codons were synthesized. Mutations were performed by PCR using the wild type hPAPS synthase expression vector (plasmid pET-19b) as template and substituted oligonucleotides as primer. Pfu DNA polymerase was used for DNA amplification. PCR consisted of 12 cycles of denaturation at 94 °C for 30 s, annealing at 55 °C for 1 min, and synthesis at 68 °C for 12 min. Once the PCR is done, Dpn I restriction enzyme was used for degrading the methylated parent template plasmid. Transformation was performed using XL1-Blue supercompetent cells and circular dsDNA. Colonies were isolated and used for fetching plasmids that possessed the correct sequence which was confirmed by DNA sequencing. Confirmed plasmids with mutations were used for transformation by using protease deficient bacteria (pLyz BL21-DE3). Further, plasmids were isolated and the sequence was verified for the presence of the appropriate mutation. Section title: Overexpression of human PAPS synthase and mutant constructs Educational score: 4.1518778800964355 Domain: biomedical Document type: Study Language: en Full-length hPAPS synthase (wildtype) and mutant hPAPS synthase plasmids were PCR amplified using primers containing Bam HI restriction sites. They were then cloned into Bam HI digested pET-19b vectors that contained proprietary 122 base pair Nco I- Nde I cassette (Veritas, Potomac, MD). The vector contained sequences for calmodulin binding site of calcineurin followed downstream by histidine tag and an enterokinase cleavage site. Transformation into competent DH-5α Escherichia coli was done as before using CaCl 2 . Colonies were isolated, miniprepped, and plasmids were sequenced for correct orientation of the initiator codon with respect to the T7 promoter sequence. Transformation was performed with expression host cells from Stratagene (BL21-DE3 plyz) using the pET-19b vectors containing the correct colned inserts with proper orientation. Section title: Preparation of bacterial cell extracts Educational score: 4.1552414894104 Domain: biomedical Document type: Study Language: en Bacteria was grown in LB broth containing ampicillin. Once the turbidity reached to A595 nm of 0.5, IPTG (1 mM) was added to the culture for inducing protein expression for 3h. After 3 h cells were centifuged to obtain the pellet. Then, 150 ml of lysis buffer (20 mM Tris-HCl, pH 7.5, containing 50 mM KCl, 1 mM dithiothreitol, 10 % glycerol, and 1.2 mg/ml lysozyme) was used for resuspending the pellet. Resuspended cells were transferred into centrifuge tubes. The original tube was then washed with100 ml of lysis buffer and the wash was added to the original cell suspension. Cell lysis was carried out at 25 °C for 7 min. The lysates were then centrifuged for 15 min at 10,000 g at 4 °C. The clear supernatants were purified by Ni + coulumn. Further purification was done by gel filtration. The purified preparations were used for enzyme assays. Section title: PAPS synthase assay Educational score: 4.101015090942383 Domain: biomedical Document type: Study Language: en Reactions were performed in a total volume of 10 μl. The enzyme reaction consisted 3 μl of reaction buffer (150 mM Tris-HCl, pH 8.0, 50 mM KCl, 15 mM MgCl 2 , 3 mM EDTA, and 45 mM dithiothreitol), 1 μl of 50 mM ATP, 3 μl of sample. The reaction was strated by adding 3 μl of inorganic [ 35 S]SO 4 (∼3.4 μCi). Reactions were carried out for 30 min at 37 °C. The reaction was stopped by placing the tubes in boiling water for 5 min. After cooling 1 μl was placed onto PEI-TLC plates. The PEI-TLC plates were chromatograped using 0.9 M LiCl solvent. Dried PEI-TLC plates were exposed overnight on to x-ray film. Section title: PAPS synthase assay Educational score: 3.6051151752471924 Domain: biomedical Document type: Study Language: en The respective radioactive spots corresponding to PAPS, APS, and SO 4 were cut out, and the liquid scintillation activity was measured by standard counts per minutes (cpm). Section title: Computational methodology Educational score: 4.254583835601807 Domain: biomedical Document type: Study Language: en Given that the crystal structures of human PAPSS1 bound to various ligands have been resolved by X-ray diffraction to a high resolution of up to 1.75 Å (PDB entries: 1x6v, 1xjq, 1xnj, 2qjf), we can utilize atomistic molecular dynamics simulations and ligand-docking techniques to gain deeper insights into the structural and functional roles of specific residues within the conserved HXGH motif, which forms part of the substrate binding pocket in the ATP sulfurylase domain. In the initial phase of this work, we used homology modeling with YASARA to address missing loop regions, conduct in silico mutagenesis, and prepare the ATP-Sulfurylase domain (ATPS) of human PAPSS1 for molecular docking studies. We used a 2.2 Å resolution crystal structure of the ATP-Sulfurylase domain of human PAPSS1, complexed with Adenosine-5′-Phosphosulfate, obtained from the Protein Data Bank (PDB ID: 2qjf ). The structure comprises two identical chains, labeled A and B. While both chains were included in all docking experiments, chain B was specifically chosen for positioning the simulation cell and serving as the receptor site for ligand docking. Section title: Computational methodology Educational score: 4.304493427276611 Domain: biomedical Document type: Study Language: en To prepare the structure for docking, all ligands, phosphate, and water molecules were removed, and hydrogen atoms were added following the standard procedure in YASARA and then the entire structure underwent energy minimization. The Mg-ATP ligand was prepared using structures from the Protein Data Bank, with YASARA's AutoSMILES feature employed for automatic force field parameter assignment. AutoSMILES utilizes SMILES strings to identify known molecules and applies the AM1BCC and GAFF . (General AMBER force field) methods for molecules not recognized. AM1BCC charges were further refined by incorporating known RESP charges of similar molecular fragments and by calculating semi-empirical AM1 Mulliken point charges , which involved geometry optimization using the COSMO solvation model . Section title: Computational methodology Educational score: 4.20939302444458 Domain: biomedical Document type: Study Language: en For molecular docking, YASARA employs AutoDock-Vina , which uses an iterated local search global optimizer algorithm to predict binding poses and a semi-empirical scoring function to evaluate and rank them. To ensure an unbiased search for binding pockets, a simulation cell was defined to extend at least 5 Å beyond all atoms of domain B. We conducted 100 docking runs in the global search mode of AutoDock Vina, as implemented in YASARA, to dock the ligands to the ATP-sulfurylase domain of human PAPSS1. Section title: Computational methodology Educational score: 4.130947589874268 Domain: biomedical Document type: Study Language: en The resulting conformations were grouped into clusters, each differing by a minimum heavy atom RMSD of 5.0 Å. From each cluster, the conformation with the highest binding energy was selected as the representative structure. Throughout the docking process, the protein structure was maintained in a fixed position, while the ligand was permitted full flexibility to explore potential binding poses. Section title: Computational methodology Educational score: 4.055173397064209 Domain: biomedical Document type: Study Language: en To validate our docking methodology, we initially re-docked Adenosine-5′-Phosphosulfate to verify that the binding site was accurately predicted as per the crystallographic data. Following this, MgATP was docked, with the conformation exhibiting the highest binding affinity selected as the representative structure within the cluster. Section title: Computational methodology Educational score: 4.173421859741211 Domain: biomedical Document type: Study Language: en We also performed in silico mutagenesis to generate single-point mutations (G427A and N426K) and a double mutant (H425A-H428A). These mutations were introduced by substituting the respective side chains within YASARA, followed by a brief 100 ps energy minimization, where non-mutated residues were constrained to avoid local structural distortions. These mutations were applied to each monomer of the ATPS domain of human PAPSS1, and energy minimization was conducted using the Amber 03 force field . to maintain consistency with the force field used during the docking studies. Section title: Computational methodology Educational score: 4.2504472732543945 Domain: biomedical Document type: Study Language: en This detailed approach enables us to examine the structural and functional effects of these specific mutations in the ATPS domain. To analyze the system's dynamics, classical molecular dynamics (MD) simulations were performed with Gromacs version 4.6.5 , utilizing the AMBER99SB force field . The system was placed in a cubic simulation box with dimensions of 10 × 10 × 10 nm and solvated using the TIP3P explicit water model . To maintain electrostatic neutrality, Na + ions were added to replace randomly selected water molecules. The system then underwent steepest descent energy minimization with a maximum step size of 0.05 Å to address unfavorable van der Waals interactions in the initial configuration. Long-range electrostatic interactions were calculated using the Particle Mesh Ewald (PME) method with a 10 Å cutoff distance, and bond lengths were constrained with the LINCS algorithm employing a fourth-order expansion . Section title: Computational methodology Educational score: 4.243812561035156 Domain: biomedical Document type: Study Language: en The parameterization of ATP ligands was carried out using the standard RESP procedure in Antechamber, with the partial charges for free Mg2+ ligands obtained from HF/6-31G∗ calculations in Gaussian03 . Histidine residues were modeled with double protonation at the ND1 and NE2 positions, whereas arginine and lysine residues were protonated according to Gromacs default settings. Section title: Computational methodology Educational score: 4.260608673095703 Domain: biomedical Document type: Study Language: en After energy minimization, each of the six systems was equilibrated by restraining the heavy atoms under constant temperature conditions with the V-rescale thermostat at 300K for 1 ns. This was followed by pressure equilibration using the Parrinello-Rahman barostat for an additional 1 ns at each temperature. Initial velocities were assigned according to a Maxwell-Boltzmann distribution at the corresponding temperature, and neighbor lists were updated every 10 fs using a group-based cutoff scheme. The minimized and equilibrated configurations were used as the starting points for all subsequent unrestrained MD simulations, which were performed for 100 ns each in the isothermal-isobaric (NPT) ensemble. Section title: Computational methodology Educational score: 4.173626899719238 Domain: biomedical Document type: Study Language: en The Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) method, implemented in Gromacs as g_mmpbsa , was used to calculate the receptor-ligand binding free energy from the trajectories. Each trajectory was reduced to 500 snapshots, and the g_mmpbsa tool was utilized with default settings for the calculations. Section title: Computational methodology Educational score: 0.8933570384979248 Domain: biomedical Document type: Other Language: en Figures were generated using Yasara and rendered with POVRay ( www.povray.org ). Subsequent editing and labeling were completed using GIMP 2.10.18. ( www.gimp.org ). Section title: Nucleophilic attack of ATP Educational score: 3.2913882732391357 Domain: biomedical Document type: Other Language: en ATP can possibly be reacted nucleophilically in four different ways. The possible nucleophilic attack of the molecule is described in Fig. 1 . Fig. 1 Mechanism of ATP use in various reaction types. ATP sulfurylase is a adenylyl transferase (Type II) and APS kinase is a Type I phosphoryl transferase. Fig. 1 Section title: Nucleophilic attack of ATP Educational score: 4.610136032104492 Domain: biomedical Document type: Study Language: en Most of the kinases are beta-gamma hydrolases. APS kinase is a beta-gamma hydrolase that splits the phosphoryl and transfers it to the recipient molecule that gets phosphorylated. In contrast the nucleophilic attack on alpha phosphoryl of ATP releases pyrophosphate (PPi) as the by product and the adenylyl portion gets added onto the attacking nucleophile. ATP sulfurylase binds inorganic sulfate and the sulfate oxy anion reacts with alpha-phosphoryl of ATP to form 5′-phosphoadenosine phosphosulfate (APS) and PPi. Thus, as classified in Fig. 1 , ATPS falls under the category of adenylyl transfer (type II) reaction. In mammals ATP sulfurylase and APS kinase are fused gene products. Human PAPSS1 (hPAPSS1) contains NH 2 -terminal APS kinase domain and COOH-terminal ATP sulfurylase domain connected by a common linker region (residues 220–265) as shown in Fig. 2 . Fig. 2 Linear amino acid sequence of hPAPSS1. Residues ∼1–265 encompasses APSK domain and residues ∼265–623 encompasses ATPS activity domain. The highlighted residues are common between two domains and mandatory for bifunctional (ATPS-APSK) activities of hPAPSS. Fig. 2 Section title: Nucleophilic attack of ATP Educational score: 4.153627872467041 Domain: biomedical Document type: Study Language: en Without the linker region both APSK and ATPS activities are negligible . The COOH-terminal domain constructed by including residues 220–623 of hPAPSS1 was cloned, expressed, purified and characterized for incresing substrates of ATP with fixed sulfate concentration and increasing ATP with fixed sulfate concentration . Line-Weaver Burk reciprocal plot (insets) indicates Km of 2.2 mM for ATP and 0.53 mM for sulfate. Fig. 3 COOH-terminal (aa 220–623) ATPS domain activity. Fig. 3 A shows increasing concentration of ATP plotted against velocity (pmol APS formed/min/mg). The corresponding inset is the Lineweaver-Burk plot of 1/s vs 1/v showing the Km value of 2.2 mM for ATP. Fig. 3 B shows increasing concentration of Sulfate plotted against velocity (pmol of APS formed/min/mg). The corresponding inset is the Lineweaver-Burk plot of 1/s vs 1/v showing the Km value of 0.53 mM for sulfate. Fig. 3 Section title: Nucleophilic attack of ATP Educational score: 4.307425022125244 Domain: biomedical Document type: Study Language: en ATPS being an alpha-beta ATP hydrolase doesn't contain typical Walker motif (GxxGxxK) as seen with APSK. APSK is a typical beta-gamma hydrolase which contains canonical Walker-A motif and ATPS instead contains conserved HNxH motif as shown in Fig. 4 below. Fig. 4 HPAPSS1 structure. The top ribbon diagram represents the dimeric structure of hPAPSS. Top Green and Silver ribbon diagram depicts APSK structure. The green ribbon structure also shows APS substrate (in red color) bound to it. The bottom yellow and silver ribbon diagram represents dimeric domain of ATPS. The circled part on the yellow ribbon possesses sequences that contains conserved HXGH motif. Fig. 4 Section title: Nucleophilic attack of ATP Educational score: 4.231940269470215 Domain: biomedical Document type: Study Language: en The full length construct containing 1–623 amino acid residues of hPAPSS1 cloned, expressed purified and characterized. The kinetics with various sulfate concentrations are represented below for wild type (WT) top panel . As can be seen for overall PAPS production (ATPS + APSK combined activities) hPAPSS1 shows typical Michaelis-Menton kinetics. The APS formation by ATPS trails APSK product PAPS at a slower rate. The bottom panel represents the kinetics exhibited by N 426 K mutant. As compared to the WT, Km for overall activity of PAPS formation (ATPS + APSK combined activities) for N 426 K mutant was ∼4X higher whereas the Km value towards sulfate was similar to that of WT. Fig. 5 Increasing substrate concentration of sulfate versus reaction velocity of APS formed by full length WT (5A) and N 426 K mutant (5B) of hPAPSS1. Fig. 5 A and B shows increasing concentration of sulfate plotted against velocity (pmol APS and PAPS formed/min/mg). Overall PAPS formed in WT and N 426 K mutant exhibited typical hyperbolic Michaelis-Menton kinetics. However the APS formed in WT reached saturation, N 426 K mutant was linear. Fig. 5 Section title: Nucleophilic attack of ATP Educational score: 4.165740966796875 Domain: biomedical Document type: Study Language: en In Fig. 6 A (the top panel) shows the response of WT enzyme towards varying concentration of ATP. The PAPS formation (solid circle) exhibits biphasic curve with first phase becoming flattening between 3 and 4 mM ATP and the second phase plateaus ∼ between 6 and 7 mM ATP with a highest Vmax reaching up to ∼120 pmol/min/mg. The N 426 K mutant enzyme also exhibits bimodal response towards ATP however the Vmax was significantly higher reaching up to 300 pmol/min/mg which is ∼3 fold higher than WT. The intermediate APS accumulated was nearly similar between WT and N 426 K reaching up to ∼120 pmol/min/mg. Fig. 6 Kinetics of full length WT and N 426 K mutant enzymes against ATP. The overall PAPS formed exhibited bimodal curve evinced both in WT and N 426 K. Fig. 6 Section title: Nucleophilic attack of ATP Educational score: 4.304874897003174 Domain: biomedical Document type: Study Language: en Since hPAPSS exhibited biphasic response towards ATP a half maximal estimate was determined to represent an approximate Km value. WT showed K0.5 of 4.3 mM and N 426 K mutant showed 3.7 mM, Km value that is slightly lower for N 426 K towards ATP. Contrary to ATP response, both WT and N 426 K mutant exhibited typical Michalis-Menton kinetics (a hyperbolic response) with a calculated Km (Lineweaver-Burk plot inset) of 0.33 mM for WT and 0.44 mM for N 426 K towards sulfate. The Vmax for N 426 K was 3–4 fold higher for ATP and sulfate compared to WT. The overall catalytic efficiency (Vmax/Km) was about 3 folds higher for N 426 K compared to WT ( Table 1 ). Table 1 Kinetic parameters exhibited by WT and N 426 K towards ATP and inorganic sulfate. Table 1 Construct K 0.5 ATP mM (half maximal estimate) Km SO 4 mM Vmax ATP pmol/min/mg Vmax SO 4 pmol/min/mg Vmax/K 0.5 ATP Vmax/Km SO 4 Wild Type 4.3 0.33 120 118 28 357 N426K 3.7 0.44 310 470 84 1068 Section title: Binding of ATP and sulfate on the active site of hPAPSS1: in silico studies Educational score: 4.4514689445495605 Domain: biomedical Document type: Study Language: en Using high-resolution crystal structures of hPAPSS1 domains complexes of wild-type and mutant hPAPSS1 with bound ATP were created and molecular dynamics simulations were performed to describe movements of the atoms over time. As can be seen in Fig. 7 in WT the two histidine's (H 425 and H 428 ) side chain imidazole ring exhibited pi-pi interaction with anti-oriented purine ring structure of ATP and the overall ATP binding energy for hPAPSS1 as calculated by MM/PBSA is ∼ -40 kJ/Mol ( Table 2 ), indicating good binding of ATP for the WT active site pocket. In contrast, when the two histidine's (H 425 and H 428 ) were replaced with alanine the R group methyl is not in close proximity for closer/fine interactions. Table 2 describes the overall binding energy differences between WT hPAPSS1 and mutants (N 426 –K, G 427 -A, and H 428 -A-H 425 -A) of the HNGH motif. As can be seen the double mutant exhibited an unfavorable binding energy for ATP. The ATP molecule which was artificially docked into the binding pocket to measure the binding energy thus would probably not stay long enough in the binding pocket, making the reaction thermodynamically impossible to take place during the intracellular time needed. The N426K mutant shows an even more favorable binding energy (−70 kJ/Mol) than WT, while the G-A mutant exhibited an unfavorable binding energy (218 kJ/Mol) for ATP. This correlates well with the experimental findings that even single mutants of the two histidine render the enzyme into a totally inactive enzyme as measured by overall PAPS assay . Fig. 7 ATP docked into the binding pocket of the sulfurylase domain of PAPSS1. ATP is depicted as a ball and stick model in green. The histidine residues H425 and H428 and their respective mutations to Alanine are shown as a stick model in red, Left panel: WT, right panel:H425A-H428A double mutant. Fig. 7 Table 2 MM/PBSA binding energies of MgATP in complex with hPAPSS1. Table 2 WT (ATP) kJ/mol G427A (ATP) kJ/mol N426K (ATP) kJ/mol H425A_ H428A (ATP) kJ/mol MM-PBSA Binding energy −40 218 −70 528 Section title: Binding of ATP and sulfate on the active site of hPAPSS1: in silico studies Educational score: 4.2969560623168945 Domain: biomedical Document type: Study Language: en In WT the ATP (depicted with silver sticks) is closer to Mg 2 + (blue ball with Yellow Font on top). Whereas in N426K mutant, after 100 ns of MD simulation the ATP phosphates were found to be significantly closer with looped structure forming even better contacts with cationic (Mg 2 + ) (Blue Ball with Yellow Font on Top). From this we predict that lysyl-ε−amino group positive charge neutralizes the repulsive forces of anionic charges and stabilizes the active site complex for nucleophilic attack by inorganic sulfate that can happen with ease. . Fig. 8 In Fig. 8 shown below the active site pocket of WT (with asparagine at position 426) is compared with the mutant enzyme replaced with basic residue lysine. Position of Mg-ATP after 100 ns of molecular dynamics simulation, left panel: WT, right panel: N426K mutant. The magnesium ion is depicted as a blue sphere while ATP is shown in grey as a stick model. Fig. 8 Section title: Binding of ATP and sulfate on the active site of hPAPSS1: in silico studies Educational score: 4.229381561279297 Domain: biomedical Document type: Study Language: en To further test the above idea, docking of inorganic sulfate was done using autodock VINA. As can be seen in Fig. 9 there are two arginine's (proximal R421 and distal R522) that are in closer proximity at a respective distance of 1.93 and 1.96 Å. Out of the four oxygens of the inorganic sulfate, two oxyanions normally bears electro negative charges. One oxyanion had to engage in nucleophilic attack and the other neutralized. As can be seen in Fig. 9 , one of the oxyanions is about 3.01 Å distance perhaps poised for nucleophilic attack with alpha phosphoryl group of ATP. Fig. 9 Sulfate docked into the ATP-PAPSS1 complex. Sulfate is depicted in green as a stick model. Fig. 9 Section title: Discussion Educational score: 4.8412299156188965 Domain: biomedical Document type: Study Language: en PAPSS synthase (PAPSS) is a bifunctional enzyme in many organisms . PAPSS produces 3′-phosphoadenosine 5′-phospho sulfate (PAPS) in two steps. In the first step inorganic sulfate reacts with ATP to form PPi and adenosine 5′-phosphosulfate catalyzed by ATP sulfurylase (ATPS) . In the second step APS kinase (APSK) uses APS and ATP to form 3′-phosphoadenosine 5′-phosphosulfate (PAPS) and ADP . PAPS is the universal sulfuryl donor. Sulfotransferases use activated sulfuryl group from PAPS to transfer, onto recipient hydroxyl containing molecule to form sulfate-ester The sulfurylated molecule receives a negative charge that changes the physicochemical properties of the molecule . Thus, PAPS production and its regulation is crucial for all biological sulfonation and consequent cell integrity and metabolism. We used human PAPSS 1 (hPAPSS1) as a model system to study the structure function. As reported earlier, the hPAPSS1 has two domain activities ATPS and APSK. Previous study delineated the regions of ATPS activity domain and APSK . As shown in Fig. 1 the ATP molecule can participate in four different ways. Most of the serine/threonine and tyrosine kinases are type I that transfers gamma-phosphoryl of ATP on to the recipient amino acid residues that gets phosphorylated . Many small molecules, one for example glucose gets phosphorylated inside the cell by hexokinases using ATP to form glucose 6-phosphate which are also Type I phosphoryl transferase. ATP sulfurylase (ATPS) is a type II that transfers adenylyl portion of ATP onto the recipient sulfate molecule to form APS and PPi . In contrast to ATPS, CTP:phosphocholine cytidylyltransferase uses CTP to transfer cytidyl group on to phosphocholine to form CDP-choline . Though type III is a possible mechanism in biological system to use ATP as the moiety for ADP transfer, thus far no known report is available to support the existence of such transferase (Venkatachalam proposed). Nonetheless, ADP transfer is a common occurrence in biological system in wide variety of organisms, as for example histone ADP ribosylation which use NAD + as the ADP donor instead of ATP . The type IV transfer involves the transfer of adenosyl group from ATP onto a recipient molecule. Methionine adenosyl transferase (MAT) is the only enzyme that falls on to the type IV category that transfers the adenosyl group from ATP on to sulfur of methionine to form the universal methyl group donor s -adenosylmethionine (SAM) . In MAT catalyzed reaction it is quite interesting that all three phosphates are released as PPi and Pi . Thus, the interplay of phosphate and sulfur metabolism is well established across organisms . PAPSS is the one and only enzyme that is known thus far to use ATP in two different mechanisms. ATPS domain activity of PAPSS is a type II and APSK domain of PAPSS is a type I transfer entities . Type I phosphoryl transfer seen with protein and small molecule kinases use typical Walker motif . APSK and putative APSK domain of all PAPSS possess typical Walker A motif GxxGxxK . In all three hPAPSS (1, 2a and 2b) the ATP binding P-loop motif contains conserved GLSGAGKT on the N-terminus. In hPAPSS1 G 59 LSGAGKT 66 is between residues 59–66 . In hPAPSS2a and 2b G 49 LSGAGKT 56 is between residues 49–56 . ATPS being a type II transfer type doesn't contain P-loop with Walker motif [ , , ] instead it contains HNxH motif . In all hPAPSS it is HNGH residues (Venk motif) that is purported to bind ATP. In hPAPSS1 “HNGH” is between residues 425–428. In hPAPSS2a it is between residues 415–418 and in hPAPSS2b it is between residues 420–423. It is interesting that the hPAPSS isoforms are about 5–10 residues apart from each other on the linear primary sequence. In this paper we present the experimental studies on the mutational effects of the HNGH motif of the hPAPSS1. In addition, the in silico studies are performed on hPAPSS1 on the HNGH motif. With hPAPSS1 the residues H 425 NGH 428 were experimentally studied for kinetic parameters. The N 426 K mutant exhibited higher Vmax and catalytic efficiency (Vmax/Km). The residue next to histidine in many organisms is substituted with arginine and the physiological significance is unknown. Perhaps in organisms which reduce sulfate to sulfide and subsequent reaction of hydrogen sulfide with O-acetylserine to form cysteine and homocysteine followed by methionine synthesis may require higher amounts of PAPS synthesized . The reductive pathway of activated sulfate PAPS into sulfite by PAPS reductase is in high demand in plants and is totally absent in mammals. This warrants a less active PAPS synthase since the product PAPS in mammals is used only for limited and specific sulfotransferase reactions . Thus, we speculate that the conversion of N into K of WT in hPAPSS leads to gain of function. In other words, nature had done the mutation to convert a more basic residue (R) seen in certain organisms (bacteria, yeast etc.) into a neutral residue as seen with mammals. This change perhaps evolved according to the PAPS demands, dictated by the respective organism. The mutation of both histidine's (H 425 and H 428 ) into alanine completely abolished its activity. The G 427 to A mutation resulted in loss of activity in the forward direction of PAPS formation and the backward reaction of PPi combining with APS to form ATP and sulfate assessed by radioactive 35 SO4 formation was much faster a paradox that we can't explain with available data (data not reported). When the C-terminus (residues 220–623) was separated from the crucial parts (1–219) of APSK domain it exhibited typical Michalis-Menton (MM) kinetics with hyperbolic response with both ATP and sulfate. On the other hand, the WT full length (residues 1–623) exhibited a bimodal/biphasic response with ATP and typical M-M response with sulfate. This response is true with full length N426K mutant as well exhibiting a bimodal/biphasic response with ATP and typical M-M response with sulfate. Thus, in fused gene product (ATPS-APSK) of PAPSS the two domains are coordinately influencing each other's activities in overall PAPS synthesis controlled perhaps by ATP availability. Our experimental data is fully supported by in silico data in terms of ATP binding energies. That is the H 425 -A-H 428 -A double mutant possessed no activity and it is corroborated by high energy required for ATP binding presented in the results section. Thus, the double mutant is highly thermodynamically unfavorable to drive the reaction. We tested this hypothesis with conserved HNGH motif of hPAPSS2b H 420 -A-H 423 -A double mutant. The mutation of two histidine's (H 420 –H 423) drastically increased binding energy for ATP a response that was less severe with hPAPSS2b compared to hPAPSS1. This means the ATP binding pocket is less stringent with hPAPSS2b compared to hPAPSS1 for ATP binding and in part explains the two isoforms are structurally different which reflects in the functional differences. Finally, when we looked at the active site binding of sulfate the reactive oxy anions are neutralized by two arginine's (R 421 and R 522 ). This makes the sulfate fixed nucleophile with one reactive oxyanion poised for nucleophilic attack of the alpha-phosphoryl of ATP to form APS and PPi. In N 426 –K mutant the loop structure in the active site pocket is drastically different making the sulfate closer to ATP than seen with WT which additionally explains the higher activity exhibited by the N 426 –K mutant. In addition, the tradeoff between substrate binding (a parameter of Km) and the product release is an orchestrated balanced event in that both WT and N 426 –K mutant exhibits similar Km for sulfate. However, Km for ATP for N 426 –K is slightly lower which in essence could alter the energetics of the product formation along with sulfate binding for product APS release. Whether APS release is the part where the observed ∼3x higher velocity seen with N 426 –K differs from WT is one of the questions that needs to be answered with reference to higher catalytic efficiency seen with N 426 –K. Section title: CRediT authorship contribution statement Educational score: 1.0201205015182495 Domain: other Document type: Other Language: en K.V. Venkatachalam: Writing – review & editing, Writing – original draft, Validation, Supervision, Project administration, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Dhiraj Sinha: Visualization, Validation, Software. Chris Soha: Validation, Software. Rudi H. Ettrich: Visualization, Validation, Supervision, Software, Methodology, Investigation, Formal analysis, Data curation. Section title: Declaration of competing interest Educational score: 0.9059566855430603 Domain: other Document type: Other Language: en The authors declare no conflict of Interest at this time. | Study | biomedical | en | 0.999997 |
PMC11697825 | Section title: Background Educational score: 2.2309482097625732 Domain: other Document type: Other Language: en Rising costs for prescribed drugs are a challenge for all healthcare systems . To limit rising costs for drugs, the German law (Social Security Code, §12 SGB V) states that drug therapies must be sufficient, appropriate, and economical and must not exceed what is necessary. Patients cannot not claim medical services that are uneconomical or unnecessary, and physicians may not provide those services . In Germany, all drugs with market authorisation when entering the market are covered by the statutory health insurance funds (SHI). The only restriction applies to the price, which depends on the additional benefits of a drug in comparison with established competitors and is stated by the Joint Committee (Gemeinsamer Bundesausschuss – G-BA). The idea is to make innovative drugs conferring relevant benefit available, while discouraging brands with high cost but negligeable or lacking advantage over established treatments . It still results in large numbers of drugs (brands) being covered by the SHI, leaving decisions and related economic considerations to prescribers. The Associations of the SHI-accredited physicians (KV) is responsible for the communication with prescribers and arbitrates the interests of SHI and physicians regarding drug prescribing and prescribing costs. Section title: Background Educational score: 1.568803071975708 Domain: other Document type: Other Language: en Surveillance procedures have been developed for the ambulatory sector to monitor prescribing costs. They are negotiated between the SHI and KV, and comprise targets, quality criteria, cut-offs etc. . Physicians who do not comply with their prescribing targets obtain individualised feedback but may ultimately suffer financial sanctions . Section title: Background Educational score: 3.986020803451538 Domain: biomedical Document type: Study Language: en In Bavaria, a state within the Federal Republic of Germany, a novel agreement (Bavarian Drug Agreement, German: Wirkstoffvereinbarung, in following WSV) was introduced in 2014 . While other states focus on absolute costs for prescribed drugs, the WSV requires the prescription of preferred drugs . The subject matter of prescriptions are DDDs , which present the average maintenance daily dose for adults (WHO) . The number of DDDs contained in each pack is calculated according to the number of tablets and the amount of drug. In the WSV 2.0, for 31 indication areas, prescribing targets consisted of proportions prescribed for recommended drugs or generics . For example, orthopaedists must prescribe 63% (WSV 2.0) defined daily doses (DDDs) of generics in ‘drugs for the treatment of bone diseases’ . ‘Recommended drugs’ are usually well-established drugs supported by evidence regarding their safety and effectiveness. They are recommended by current guidelines and frequently available as generics or biosimilars. In 2018 and 2019, for example, when conducting our interviews with gastroenterologists, 39% of their prescribed DDDs within ‘TNF-alpha-inhibitors’ had to be for the following four recommended drugs: Benepali® = etanercept, Flixabi® = infliximab, Inflectra® = infliximab, and Remsima® = infliximab . Section title: Background Educational score: 2.116276502609253 Domain: biomedical Document type: Other Language: en The proton pump inhibitor (PPI)-drug target restricts the amount of prescribed DDD per patient. Therefore, physicians have limited PPI-DDD (20 mg omeprazole = 1 DDD) per patient. The number per patient is an average number, so higher DDD numbers for one patient can be levelled by narrow DDD numbers of other patients. Section title: Background Educational score: 1.2063422203063965 Domain: other Document type: Other Language: en Targets are adapted to specialisation groups . Section title: Background Educational score: 1.9239810705184937 Domain: biomedical Document type: Other Language: en Every quarter, physicians receive feedback by the KV on whether and to what extent prescribing targets have been met. Additionally, all targets are weighted according to the prescribed DDD-volume and various factors (e.g., costs and additional benefits) and are cumulatively calculated as a so-called overall target covering all drug prescriptions issued by a particular practice . Fig. 1 Feedback regarding overall targets—modified according to the KV Section title: Background Educational score: 1.3241723775863647 Domain: other Document type: Other Language: en Despite the detailed feedback mechanism and the potential threat of financial sanctions, some physicians fail to reach their overall target in the long term. Section title: Background Educational score: 2.219613790512085 Domain: biomedical Document type: Study Language: en As part of the project WirtMed—the prescription of medicines: Audit and Control of Efficiency and Quality funded by the Innovation Fund of the Federal Joint Committee (G-BA), we focussed on physicians repeatedly missing their prescribing targets. The aim was to understand the prescribing behaviour of these physicians by exploring associated beliefs, reasons for prescribing drugs, which are not recommended, and barriers against compliance with the WSV and coping strategies in a qualitative study. Section title: Background Educational score: 1.764811635017395 Domain: biomedical Document type: Other Language: en We already reported on indicators to be used for prescribing surveillance aiming cost control based on prescription data . Section title: Methods Educational score: 2.4986560344696045 Domain: biomedical Document type: Study Language: en For this study, we used a qualitative design to explore this research area and generate hypotheses for missing drug targets. We conducted semi-structured interviews with physicians who missed their prescribing targets during the observation period from the second quarter of 2017 to the first quarter of 2018. These outliers were defined as: Section title: Methods Educational score: 1.2932159900665283 Domain: other Document type: Other Language: en less than 85% overall target achievement under the WSV, and less than 3% improvement regarding the overall target achievement in two sequential quarters. Section title: Methods Educational score: 1.8708542585372925 Domain: biomedical Document type: Study Language: en Physicians meeting these criteria were identified by the Bavarian KV (KVB). In Germany, there are physicians of different specialisation groups in ambulatory care, usually without hospital affiliations. Therefore, we did not restrict invitations to any primary or secondary care specialisation groups. Physicians thus identified received a letter from the KVB, which included an invitation from the Philipps-University of Marburg (Department of General Practice) and Friedrich-Alexander-University of Erlangen (Department of General Practice) to participate in the study. If interested, physicians were asked to contact the Department of General Practice of the Philipps-University Marburg to arrange an interview. The KVB thus received no information on who participated in the survey. Section title: Methods Educational score: 3.7931764125823975 Domain: biomedical Document type: Study Language: en JG (female, pharmacist) developed an interview guide covering participants’ practice philosophy, relationship with their patients, prescribing behaviour, professional learning and staying up-to-date, experiences with the WSV, and opinions on prescribing surveillance (see supplement, S1: interview guide). JG and NL (female, social scientist) pretested the interview guide with physicians of the research teams in Marburg and Erlangen. The interviews started with more general topics and gradually approached the contentious area of drug prescribing. JG and NL jointly conducted the interviews. The interviews took place in participants’ practices between December 2018 and July 2019 and were conducted in German. JG made fieldnotes (including experiences and impressions) during and after the interviews, which were subsequently discussed between JG and NL. The interviews were recorded and transcribed by an external service provider. JG coded the transcripts using MAXQDA. JG developed a code tree, which was continuously modified in discussion with another researcher who in parallel coded 13 interviews. With the improved tree JG coded the second 13 interviews, resulting in only very little further modifications of the code tree. The resulting final code tree was used by JG for the final coding of all 26 interviews. We used an inductive-deductive procedure, which is oriented towards the qualitative content analysis, according to Mayring and Fenzl . Deductive codes evolved from the interview guide, and inductive codes resulted from the contents of the interviews. Coding and data analyses started after conducting the first interviews. We presented and discussed results continuously to the research team. For choosing the quotations for the result section we first built the main massage of the single code and then identified the most pertinent citations. We undertook further selection according to brevity and fit with other utterances. The authors translated the German quotations by participants into English. A professional service undertook language editing of the paper with additional checks of quotations by authors. Section title: Methods Educational score: 0.9416621327400208 Domain: biomedical Document type: Other Language: en We obtained permission from the ethics committee of the Philipps University of Marburg . This part of the subproject of the WirtMed study was registered with the German Register for Clinical Studies . Section title: Methods Educational score: 1.7578076124191284 Domain: biomedical Document type: Study Language: en In the following, we mentioned brand names of drugs only if they were an explicit topic of participants’ adherence. We present original quotations with the following coding: TPD1819-XY (TPD = subproject D (German: Teilprojekt D), 1819 = interviews conducted in 2018 and 2019, XY = number of interview). Section title: Study sample Educational score: 2.969594717025757 Domain: biomedical Document type: Study Language: en The KVB identified a total of 401 practices out of about 13,600 in Bavaria as failing to meet their targets and sent them invitation letters. 34 responded and gave their consent to take part in the study. Six dropped out because of lack of time or interest. 28 interviews were scheduled, and we conducted 26 of those (length of time 30 to 105 min). The research-team decided to cancel the last two interviews (number 27 and 28; specialisation group: orthopaedist) due to reaching the theoretical saturation from repeating the contents of former interviews (challenging drugs and reasons for prescribing were the same or very similar in all interviewed orthopaedists; we therefore did not expect any additional findings from the two interviews with this already well-represented specialisation group). The sample was composed of physicians of the characteristics and specialisation groups listed in Table 1 . Table 1 Description of the study sample Characteristics Number of Participants Age 41–50 years 6 51–60 years 17 > 60 years 3 Sex Male 21 Female 5 Practice Location City 5 Smaller city 18 Countryside 3 Specialisation Group Cardiologist 1 Child and youth psychiatrist 1 Gastroenterologist 2 General practitioner 3 Haematologist and Oncologist 2 Neurologist 2 Neurosurgeon 1 Ophthalmologist 1 Orthopaedist 9 Paediatrist, sub-specialisation rheumatology 2 Surgeon 2 Total number of participants: n = 26 Smaller city: < 100.000 inhabitants City: > 100.000 inhabitants Section title: Qualitative findings: prescribing practice Educational score: 2.1528818607330322 Domain: biomedical Document type: Study Language: en Most of the interviewed physicians were unhappy about being an outlier, which the interviewers recognised due to emotional and/or intense speech of the participants (special emphasis shown in capital letters). There are different mechanisms influencing the prescribing behaviour resulting in being an outlier (Table 2 ). Table 2 Mechanisms influencing the prescribing behaviour of outliers (no defined order) Mechanisms effecting the prescribing behaviour of outliers Competing demands Limited decision latitude Adequacy of indicators Lack of knowledge regarding WSV Faulty beliefs Ease and safety of application Coping strategies Medical information management Section title: Qualitative findings: prescribing practice Educational score: 1.6014240980148315 Domain: biomedical Document type: Other Language: en These mechanisms we present more detailed in the following. Section title: Competing demands Educational score: 1.6235824823379517 Domain: clinical Document type: Other Language: en Patients asking for drugs and/or manufacturers (brand instead of generic) often leads to a breach of cost-effectiveness principles: ‘One prescription […]doesn’t cost me any nerves in the total bill. But it costs me a quarter of an hour of hoarseness to explain to the patient why […] [I] will NOT prescribe him this drug’ . Physicians explain being tired of this kind of discussion with their patients and try to avoid them by acquiescing to patients’ demands. Section title: Competing demands Educational score: 2.1504433155059814 Domain: biomedical Document type: Other Language: en Participants report having to change the drugs they have prescribed over years also represents a particular challenge. They state, having to explain that another drug is preferable puts themself in a contradictory position. In these cases, physicians feel that their competence is contested. This feeling seems to be particularly strong with biosimilars, which according to the WSV, have to be prescribed preferentially. Participants criticise, first they told their patients why one drug (brand) was right for them, and now they must explain why another drug (biosimilar) is appropriate. Section title: Competing demands Educational score: 1.5269607305526733 Domain: biomedical Document type: Other Language: en Participants mention patients regard cheaper drugs as being of poorer quality. They also try to convince their patients that this is not the case, but they are not always successful. A few patients even change to another practice to obtain prescriptions of their preference. Section title: Competing demands Educational score: 2.3536269664764404 Domain: biomedical Document type: Other Language: en Some physicians did not meet the oral anticoagulant target because they prescribe direct oral anticoagulants (DOACs) too frequently instead of vitamin-K-antagonists (VKA). They stress the ease of administration and fewer visits for blood monitoring, thus saving staff time and costs. Participants also mention to save staff time and costs by prescribing the biological Humira® (adalimumab) for inflammatory bowel disease (IBD) because it can be administered by the patient at home (see ease and safety of application). Section title: Competing demands Educational score: 1.8978148698806763 Domain: biomedical Document type: Other Language: en Thus, physicians feel their competence is challenged if they change drug therapies to meet prescribing targets. Their acceptance by their patients and the economic viability of their practice are at stake, which has a relevant influence on prescribing behaviour. Section title: Limited decision latitude Educational score: 1.7318745851516724 Domain: clinical Document type: Other Language: en Prescribing drugs after initiation by other physicians is a reason for not following the WSV. Participants state, patients often ask them for repeat prescriptions that do not conform to prescription targets: ‘It must have been a patient who got it from someone else for some reason, and I said, “Okay, then you’ll get it from me, too”’ . In this case, physicians explain not to question the decisions made by their colleagues. Section title: Limited decision latitude Educational score: 1.94253408908844 Domain: biomedical Document type: Other Language: en In addition, physicians mention being uncertain whether switching to biosimilars might cause the risk of litigation in case of side effects or complications. Some state, for example, that although the structure of the protein is the same, the preparation is not always identical regarding its composition and further ingredients. Section title: Limited decision latitude Educational score: 1.7021992206573486 Domain: biomedical Document type: Other Language: en Some participants report that patients with special management problems are referred to them. They explain advanced or more severe illness often requires the prescription of second or third-line drugs, which are usually not in line with the requirements of the WSV. Section title: Adequacy of indicators Educational score: 2.3870012760162354 Domain: biomedical Document type: Study Language: en The participants criticise that the addition of new drugs to the list of recommended drugs often happens only after long delays. They state that the preference of well-established and cost-effective drugs prevents patients from obtaining new and, in participants’ view, more effective or safer drugs. For a long time, the WSV stipulated the prescription of VKAs instead of DOACs, and only a few DOACs (e.g., apixaban and edoxaban) were added to the list of recommended drugs. However, a certain percentage of VKA prescriptions is still required. Participants maintained that the WSV is lagging with regard to the accommodation of new drugs. Section title: Adequacy of indicators Educational score: 1.6075916290283203 Domain: biomedical Document type: Other Language: en Some physicians recognise there are conflicts between guidelines and preferred drugs within the WSV. They mention drugs for multiple sclerosis (MS) and obsessive–compulsive disorder in children as examples. Participants cover, in this case physicians who e.g., have a sub-specialisation for MS run the risk of prescribing recommended drugs not frequently enough. Section title: Lack of knowledge regarding WSV Educational score: 1.6588659286499023 Domain: other Document type: Other Language: en Participants are familiar with the WSV, but detailed knowledge about the different drug targets is sometimes missing. For example, some physicians seem to be confused about handling drugs covered by discount contracts by the insurance of a particular patient. They describe, at first, they had chosen drugs covered by discount contracts, but after the expiration of a discount contract, they risk missing a target if the drug is neither generic nor preferred. So, physicians state, if they prescribe drugs with discount contracts, which they are required to do, this could, in some cases, lead to missing the drug targets of the WSV. As a result of these changes, participants lost track of the various details and applicable regulations for single drugs, and discount contracts are part of the confusion. Section title: Lack of knowledge regarding WSV Educational score: 2.713367462158203 Domain: biomedical Document type: Other Language: en Furthermore, participating physicians state, they had other PPI-equivalent dosages in mind than the WSV requests, such as 40mg pantoprazol, assumed to be equivalent to 20mg omeprazol. They explain, in contrast the WSV defines 1 PPI-DDD being equivalent to 20mg omeprazol or 20mg pantoprazole. In fact, this is important because the target refuses 2 DDD for PPI prescribing. Section title: Lack of knowledge regarding WSV Educational score: 1.523437738418579 Domain: biomedical Document type: Other Language: en Most of the interviewed physicians mention helplines and advice by the KVB to clarify issues regarding the WSV, resulting in improvements in reaching their targets. Section title: Lack of knowledge regarding WSV Educational score: 1.6117662191390991 Domain: other Document type: Other Language: en Some participants experience the WSV as a very complex surveillance procedure, and some do not understand all the requirements. For example, one reports he is not familiar with the concept of DDD. Some physicians have not grasped the fundamental difference between the WSV and the previous surveillance policy. Financial budgets were calculated for the latter, which practices were allowed to exceed only if their practice had special characteristics. Those participants seem not to know that for the WSV, budgets are no longer calculated and are replaced by targets measured and specified by DDDs. Section title: Faulty beliefs Educational score: 3.763979196548462 Domain: biomedical Document type: Other Language: en Patients with osteoporosis should preferably receive generic drugs, and bisphosphonates are available in generic form. However, most of the participating orthopaedists state missing their prescribing target by often preferring denosumab (only available as Prolia®). These physicians consider Denosumab to be ‘actually almost unrivalled’ and ‘a real advance’ . They feel that it prevents bone loss and promotes bone formation, while bisphosphonates only prevent further bone loss. Furthermore, they mention very low bone mineral density (BMD) as an indication for choosing denosumab for its better ‘mechanistic evidence’. Likewise, because of the limited duration of therapy for bisphosphonates, physicians feel the necessity of switching to another drug. Section title: Ease and safety of application Educational score: 3.0225346088409424 Domain: biomedical Document type: Other Language: en Guidelines recommend Adalimumab (at the time only available as Humira®) and infliximab for treating IBD. The WSV, however, recommends only infliximab biosimilars. Participants justify preferring adalimumab for IBD instead of the biosimilar infliximab with patient comfort due to independent subcutaneous application at home, while infliximab is administered intravenously: ‘[Humira® is] Much more comfortable, because they don’t have to come to the practice every six or eight weeks and be monitored for four hours, they just do it themselves. The effectiveness is about the same, maybe even a little better here and there.’ . Section title: Ease and safety of application Educational score: 2.6405441761016846 Domain: biomedical Document type: Other Language: en One participant experienced several patients with severe anaphylactic reactions after infliximab infusions (no further specification of whether biological or biosimilar, the argument was just related to the antibody infliximab), which is why he prefers prescribing adalimumab due to the better risk profile: ‘[adalimumab is] from the way of production NOT so allergenic or actually not allergenic at all. Therefore, much less risky for the patient.’ . Section title: Ease and safety of application Educational score: 2.1681253910064697 Domain: biomedical Document type: Other Language: en While missing the drug target ‘drugs for the treatment of bone diseases’, some physicians perceive the subcutaneous application of denosumab every six months as an advantage compared to weekly oral bisphosphonates. Further participants reason the therapy with denosumab with the possibility of avoiding gastrointestinal side effects such as oesophagitis. Section title: Coping strategies Educational score: 2.3466877937316895 Domain: biomedical Document type: Study Language: en To avoid becoming an outlier, participants have developed coping strategies. For example, some physicians prescribe drugs conforming to targets themselves but refer patients in need of other drugs elsewhere. Accordingly, physicians accepting these referrals complain: ‘[…] then I’m more likely to be the one who is referred to, because if it’s approved and there’s no option, then I write the prescription.’ . As a result, because of a high proportion of uneconomical prescriptions, they describe becoming an outlier. One physician reports that he would treat patients and apply the injection but before he sent his patients to other physicians to obtain a prescription. Sending to out-patient care units of hospitals is another mentioned way of avoiding drug prescriptions which are not recommended by the WSV. Another participant states some drugs, for example, PPI in addition to NSAID therapy preventing gastrointestinal-side effects, are prescribed privately to be paid for by patients themselves to avoid missing the prescribing targets. Section title: Medical information management Educational score: 1.5572987794876099 Domain: biomedical Document type: Other Language: en Almost all participating physicians report being regularly visited by pharmaceutical representatives. They regard pharmaceutical representatives as an important source of information for new drugs and medical devices. Section title: Medical information management Educational score: 1.358554482460022 Domain: other Document type: Other Language: en Most participants are happy to receive advice from the Bavarian KV (print material or in person). However, they often discovered that letters or messages had gotten lost, which may have contributed to their incomplete knowledge of the WSV. Section title: Discussion Educational score: 2.275700330734253 Domain: biomedical Document type: Other Language: en Participants are missing their prescribing targets for a variety of reasons. When prescribing, they have to accommodate the evidence base of available drugs, health economic prioritisation, influence by pharmaceutical manufacturers, their patients’ expectations, and the norms of their profession. Specific behaviours, such as prescribing drugs not recommended or missing generic targets, pose a risk to become an outlier. These are associated with beliefs, norms and conflicting expectations. Some of these reflect true dilemmas, others, however, result from misunderstandings, lack of information or values not consistent with the WSV. In the following, we discuss the reasons mentioned and their justification and set them in a scientific, economic, and political context. Section title: Competing demands Educational score: 2.099482774734497 Domain: biomedical Document type: Other Language: en Patients’ demands influence physicians’ behaviour, especially requests for specific drugs and tests, which was also shown in different studies, for example, in a qualitative study among patients in primary care or oncology . Not all of these are to be preferred from a medical or cost-effectiveness perspective. Tactics to deal with problematic patient requests should be disseminated to make prescribers more effective in this regard. Section title: Competing demands Educational score: 2.5676894187927246 Domain: biomedical Document type: Other Language: en Participating physicians prefer DOACs to VKAs to avoid complex monitoring and, thus, to reduce their costs, which is also shown as a benefit of DOACs in other studies . This is also the case when prescribing adalimumab, which, in contrast to infliximab, does not require a longer stay in the practice and follow-up after the infusion, as is the case with infliximab . In Germany, practices are privately owned. By prescribing drugs and saving staff time, which is not preferred from the WSV perspective, physicians can thus shift costs to the insurance covering more expensive drugs . Section title: Limited decision latitude Educational score: 2.222069263458252 Domain: biomedical Document type: Other Language: en Frequently, physicians are confronted with requests for the continuation of a prescription that they have not initiated themselves. The more treatments for chronic disease are available, which must be prescribed continuously, the more frequently this situation arises. Also, the fact that German primary care physicians cannot control their patients’ access to secondary care (absence of gatekeeping), puts a central assumption of the WSV in question, i.e., that each prescriber has full control over their prescribing. Since hospital physicians are not subject to the WSV, they often prescribe drugs, leading to conflicts with the WSV once the patient has been discharged to ambulatory care. This intersectoral challenge was also found in another subproject of the WirtMed project . This is a deficiency of all systems surveying drug prescribing in Germany. Section title: Limited decision latitude Educational score: 3.280461311340332 Domain: biomedical Document type: Study Language: en Other authors demonstrated physicians’ prescribing behaviour to be influenced by fear of litigation , especially switches to biosimilars . That’s one reason for not switching biologicals to biosimilars and preferring biologicals. While our interviews were conducted, the context for this decision changed. In 2018, a phase III study showed the equivalence of adalimumab biological and biosimilars regarding efficacy, safety, and immunogenicity in patients with psoriasis, where adalimumab is approved as well . This research addresses the scepticism of physicians and patients and provides a basis for argumentation and reducing the fear of litigation. Section title: Adequacy of indicators Educational score: 3.5686376094818115 Domain: biomedical Document type: Other Language: en When the WSV was introduced, preferential prescribing of VKA was recommended, with DOACs encouraged only for selected indications. Later, a second and lower-ranking recommended drug target within prescribing DOACs (recommended drugs: apixaban, edoxaban) was introduced . However, even after this update, participants still missed their drug targets regarding DOACs. This case demonstrated the dilemma of surveillance systems such as the WSV: when including new drugs, they can be ‘too quick’ by permitting drugs with limited evidence base and high cost or ‘too slow’ by preventing effective and safe new drugs from reaching patients. Section title: Adequacy of indicators Educational score: 3.8656327724456787 Domain: biomedical Document type: Review Language: en Various drugs are available for the therapy of MS. In particular, therapy with glatiramer acetate and interferon beta 1b has long been seen as first-line therapy, and therapy started with them . Accordingly, these substances were also found as recommended drugs within the framework of the WSV, while the monoclonal antibodies alemtuzumab and natalizumab were not . Younger patients with a high number of relapses benefit from early use of a high escalation level . For these cases, monoclonal antibodies, such as natalizumab or alemtuzumab, are recommended by the German guidelines for MS . Physicians who sub-specialise in MS treat many young patients with multiple relapses and/or many patients with advanced MS and, therefore, prescribe a high proportion of drugs not recommended. Section title: Lack of knowledge regarding WSV Educational score: 1.5698672533035278 Domain: biomedical Document type: Other Language: en The impression arose while analysing the interviews that some physicians have been reluctant to familiarise themselves with the regulations of the WSV, prescribing targets, feedback procedures, differences between the previous and current surveillance procedures, etc. This contrasts with the information provided by the KVB in written form, web presentations, and even individual consultations. Section title: Faulty beliefs Educational score: 3.4075686931610107 Domain: biomedical Document type: Review Language: en Despite different postulated mechanisms, bisphosphonates and denosumab show comparable effects on fracture risk . In addition, the fracture risk-reducing effect of bisphosphonates does not seem to correlate with an increase in bone density . Guidelines, therefore, restrict BMD measurements to a few exceptions . Still, participants felt a need to monitor their patients’ BMD, thus producing ‘treatment failures’ . Section title: Ease and safety of application Educational score: 3.502641439437866 Domain: biomedical Document type: Other Language: en Infliximab-biosimilars are recommended by the WSV. However, they are administered intravenously over two hours, and patients have to stay in practice for one to two hours for observation regarding allergic reactions [ 31 – 34 ]. After three infusions, the infusion duration could be shortened to one hour [ 31 – 33 ]. The corresponding adalimumab (Humira®) can be self-administered at home . After approval of a subcutaneous form in 2019 for rheumatic arthritis, since 2020, intravenous infliximab can be switched to subcutaneous infliximab in IBD as well . However, the possibility of switching came to light after conducting our interviews. Section title: Ease and safety of application Educational score: 2.410184144973755 Domain: biomedical Document type: Other Language: en Even if most adverse drug reactions occur with low frequency, some physicians experience patients with adverse drug reactions more frequently than others due to small sample fluctuations . This personal experience based on very small samples may lead to distorted beliefs and prescribing, making outlier status more likely. It also shows that drug prescribing is often based on personal experience, which, for many, carries more weight than research evidence. Section title: Ease and safety of application Educational score: 3.6259710788726807 Domain: biomedical Document type: Other Language: en Gastrointestinal side effects with bisphosphonates should not motivate a switch to denosumab. Often, they result from incorrect intake and can be reduced through better patient education . The parenteral application appears more convenient to some patients. One study with a cross-over design showed compliance to be lower with oral bisphosphonate once a week than with parenteral administration of denosumab every six months . In our view, this underlines the importance of effective patient education. Section title: Coping strategies Educational score: 2.713773012161255 Domain: biomedical Document type: Other Language: en Referring patients to other physicians was a common practice under previous surveillance procedures based on prescribing costs. Primary care physicians, for example, could ease their prescribing budget by referring patients to specialists with more generous budgets. With the WSV, however, based on preferred drugs and generics, the absolute costs of a prescription are no longer relevant. Some referrals thus seem to arise from not having understood the requirements of the WSV . Under the WSV, only referrals for prescriptions not appearing in the list of preferred drugs have a certain rationale for an individual prescriber, who may thus avoid missing their targets. Referrals exclusively motivated for economic reasons increase the complexity of chronic care, are time-consuming and often costly for the patient, and, because referrals are often accompanied by too little information, they increase the risk of medication errors. Section title: Medical information management Educational score: 1.827711820602417 Domain: biomedical Document type: Other Language: en The conservativism inherent in the WSV seems to clash with the pharmaceutical industry’s efforts to promote novel treatments, which are usually not available as generic formulations. However, since quotas are considerably below 100%, innovative drugs that do not fulfill the requirements of the WSV can be prescribed. Section title: Medical information management Educational score: 3.3412535190582275 Domain: biomedical Document type: Review Language: en As the example of denosumab shows, expensive medicines are not automatically better than cheaper ones (see above). Exposure to the advertising of novel drugs by the industry may lead to increased drug costs . A systematic review describes that physicians with low exposure to pharmaceutical promotion show an increased prescribing of generic drugs . Furthermore, this review suggests that primary care physicians with more exposure to pharmaceutical promotion show less adherence to guidelines and prescribe a wider range of drugs . If pharmaceutical representatives are used as a source of information and represent one of the main sources of information, this influences beliefs and the physician’s prescribing behaviour. This will also be the case for pharma-sponsored journals and conferences. Section title: Surveillance policies Educational score: 1.939371943473816 Domain: biomedical Document type: Study Language: en This study examined the prescription of drugs within the framework of the WSV. The physicians are not always sufficiently informed about the requirements, even if they received in-person support from the Bavarian KV. Section title: Surveillance policies Educational score: 3.4553050994873047 Domain: biomedical Document type: Other Language: en For prescribing drugs, physicians have to consider not only the indication, comorbidities, and simultaneous treatments but also requests formulated by their patients, expectations by their profession, current guidelines, and the results of clinical trials. All measures addressing the economy of drug prescription thus increase the cognitive and, potentially, the financial burden for prescribing physicians. Since all drugs with a market authorisation in Germany are covered by the SHI, additional measures to contain costs are needed, such as the WSV and comparable surveillance policies. In essence, this leads to bedside rationing [ 44 – 46 ]. A restriction on the range of drugs covered by the SHI has been attempted in the past (‘Positivliste’) but was stopped by the federal government, not least because of pressure from the pharmaceutical industry [ 47 – 50 ]. The only regulation concerning the healthcare system is prices for novel drugs. Only if the joint committee decides that a new drug has benefits compared to established treatments can manufacturers obtain a higher price, which must be negotiated with SHI. Section title: Implication for the future Educational score: 1.908332347869873 Domain: biomedical Document type: Other Language: en The physicians’ evaluation of their practice seems to differ from the feedback provided by the WSV. In this case of cognitive dissonance, it is important to understand and respect physicians’ attitudes and challenges and find solutions for the problems and dilemmas addressed by our interview study. Section title: Implication for the future Educational score: 3.537339210510254 Domain: biomedical Document type: Other Language: en To understand and support physicians, especially outliers, and still achieve the objectives of the surveillance policies, we have the following suggestions: surveillance policies should be designed and function in a way to avoid unnecessary complexities; information about surveillance and feedback procedures must be available in an easily accessible form; efforts must be made to understand prescribing behaviour, barriers against rational prescribing, and compliance with regulations, such as the WSV, to help develop specific interventions targeted at the mechanisms identified in our study; strengthen drug information and prescribing independent of commercial interests; a system-wide decision regarding the covering of drugs by SHI would be a relief for physicians and reduce the burden of bedside rationing. This, however, will place the onus on central institutions, such as the joint committee and/or the federal government, to introduce appropriate legislation; conflicts of intersectoral (hospital and ambulatory sector) can only be avoided by establishing surveillance procedures for the hospital sector in parallel to ambulatory care; moreover, surveillance should differentiate between first prescribers of problematic drugs and practices issuing repeat prescriptions; and to support physicians, additional information campaigns aimed at the general public and patients should be developed. Section title: Implication for the future Educational score: 1.334112524986267 Domain: biomedical Document type: Other Language: en There is not enough space to discuss surveillance procedures, indicators (targets), cut-offs etc. Therefore, see our analyses regarding analysing prescribing data . Section title: Strengths and limitations Educational score: 2.227764368057251 Domain: biomedical Document type: Study Language: en Participating physicians might predominantly be those physicians, who are interested in the research topic. Although an independent academic institution was asked to conduct the study, potential participants may have feared being unduly charged with inappropriate prescribing behaviour, which may have prevented some from participating. Despite the low number of attendees, this study is relevant to understanding why physicians struggle with their prescribing behaviour and their drug targets. Based on these insights, surveillance policies can be improved, which will result in better prescribing. Section title: Strengths and limitations Educational score: 1.6731568574905396 Domain: biomedical Document type: Study Language: en To avoid bias and conflict of interest, this study has been conducted by independent, university-based researchers. Nevertheless, preconceptions by members of the research team may have influenced the conduct of interviews and analysis of the text material. Section title: Strengths and limitations Educational score: 2.2813050746917725 Domain: biomedical Document type: Study Language: en This study only interviewed physicians who had missed their overall targets. For this reason, findings regarding their beliefs and behaviours cannot be generalised to the majority who have met their targets. Moreover, not all specialisation groups were represented in our sample. Still, we think that the beliefs and expectations (mechanisms) identified apply to other clinical areas, sectors and specialisation groups. The dynamic nature of drug targets, surveillance procedures and the drug market present a challenge to research of this kind. This is not necessarily an argument against our results or conclusions but underlines the need to repeat surveys of this kind at regular intervals. Section title: Conclusion Educational score: 2.257167339324951 Domain: biomedical Document type: Study Language: en Only few physicians miss their drug targets and become outliers. We demonstrate mechanisms and challenges in prescribing behaviour (e.g., competing demands). Discussion with study participants also demonstrates the ambiguity of innovation: innovators can be physicians looking for the best available treatments for their patient, but there are also those, who uncritically follow the latest fashion, being victim to pharma marketing. While there are some criticisms of the WSV, there are other mechanisms, which are related to physicians’ behaviours and values (e.g., medical information management). Surveys as reported by us should regularly be conducted to explore reasons for problematic behaviours and develop interventions to improve prescribing. Section title: Supplementary Information Educational score: 1.4485911130905151 Domain: biomedical Document type: Other Language: en Supplementary Material 1. | Other | other | en | 0.999997 |
PMC11697834 | Section title: Background Educational score: 3.971778631210327 Domain: biomedical Document type: Review Language: en Lung cancer currently has the second highest incidence rate and the highest cancer-related death rate globally. In China, it ranks first for both. In 2020 alone, there were 820,000 new lung cancer cases and 720,000 lung cancer-related deaths in China. Thus, lung cancer poses the greatest threat to human health and life, while also imposing an immense economic burden on patients . The diagnosis and staging of lung cancer increasingly rely on minimally invasive interventional procedures, including imaging-guided lung mass biopsies, bronchoscopic brush biopsies, bronchial biopsies, and lung peripheral nodule sampling biopsies under magnetic levitation navigation. Given the rapid development of personalized lung cancer treatments, pathologic typing and molecular pathology results are essential to guide therapeutic decisions. Consequently, obtaining adequate and representative specimens on-site is of utmost clinical importance, as it can reduce unnecessary repeat procedures and expenses, thereby conserving medical resources. Section title: Background Educational score: 4.029526710510254 Domain: biomedical Document type: Review Language: en Currently, on-site judgments primarily utilize Diff-Quik staining. Compared to traditional Hematoxylin and Eosin (HE) staining and Papanicolaou staining, the Diff-Quik process significantly shortens staining time but provides less nuclear detail. Most domestic pathologists are unfamiliar with this technique and require specialized training to gain proficiency. Additionally, full-time cytologists, whether domestic or international, typically have high workloads, and there is a shortage of qualified personnel [ 3 – 5 ]. As a result, at least 30 min is required for an expert to provide on-site judgment of a single case, which is both inefficient and costly. Some hospitals resort to quick training programs to enable interventional clinicians to screen films on-site or employ remote cytology consultations via the internet after scanning films [ 6 – 8 ]. However, the former leads to lower diagnostic accuracy, while the latter necessitates significant capital investment and consumes valuable time and resources from superior hospitals. With advancements in digital imaging and machine learning, artificial intelligence-assisted cytology shows promise for rapid on-site diagnoses while reducing human subjectivity and increasing repeatability. Section title: Background Educational score: 4.028713226318359 Domain: biomedical Document type: Study Language: en ResNet-18 is a convolutional neural network with an 18-layer architecture, comprising 17 convolutional layers and one fully connected layer. It can be trained by inputting pre-processed images and then used to classify new, unknown images. ResNet-18 has been successfully applied in medical imaging diagnostics, including radiology, histopathology, and cytopathology [ 9 – 12 ], though it has not yet been used for on-site cytopathology of respiratory specimens. This study aimed to assess the performance of an improved ResNet-18 classification model as an aid in on-site determinations of respiratory cytopathology samples. Section title: Sample information Educational score: 4.093986988067627 Domain: biomedical Document type: Study Language: en A total of 739 respiratory specimens with on-site diagnoses were collected at our hospital from January 2022 to March 2023. Positive cases included those with biopsy or cell block confirmation and immunohistochemical verification of diagnosis. The sample comprised 96 squamous cell carcinoma cases, 64 adenocarcinoma cases, 6 non-small cell carcinoma cases (which could not be definitively categorized as squamous cell carcinoma, adenocarcinoma, or small cell carcinoma by morphology and immunohistochemistry), 50 small cell carcinoma cases, 1 carcinoid case, and 20 normal cytology cases, where biopsy, clinical data, and imaging showed no malignancy. A MAGSCANNER KF-PRO-005 digital pathology slide scanner (Zhejiang Ningbo Jiangfeng Bioinformation Technology Co., Ltd.) scanned Diff-Quik stained slides at 200X magnification to generate whole slide images (WSIs), automatically focusing on the smears. Two senior cytologists then captured 400X magnification images with a 2048 × 1024 pixel resolution. In cases of disagreement, another chief physician arbitrated and selected consensus images. Generally, 3–20 + images were captured per case. Images were de-identified before model testing. Section title: Image selection and representation Educational score: 3.779310464859009 Domain: biomedical Document type: Study Language: en To illustrate the diversity and diagnostic challenges of the dataset, we included representative images from each diagnostic category. These images were selected based on their quality and the presence of characteristic features relevant to the diagnosis. The selected images represent carcinoid, normal cells, adenocarcinoma, squamous cell carcinoma, non-small cell carcinoma, and small cell carcinoma. Each image was annotated with its corresponding diagnosis and used in the training and testing of the ResNet-18 classification model (Please refer to supplementary Data – Sample Information file). Section title: ResNet-18 classification model Educational score: 1.6132816076278687 Domain: biomedical Document type: Other Language: en The artificial intelligence ResNet-18 classification model used in this study was developed in collaboration with the Suzhou Research Institute of the Chinese Academy of Sciences and Lishui Municipal Central Hospital. The model employs a ResNet-18 network enhanced by convolutional block attention modules (CBAM) . Section title: Workflow for Rapid On-Site diagnosis Educational score: 3.7302024364471436 Domain: biomedical Document type: Other Language: en To visualize the process of rapid on-site diagnosis in respiratory cytology, we developed a comprehensive workflow that outlines the steps from sample collection to diagnostic conclusion, incorporating both AI and pathologist evaluations. The workflow integrates deep learning models to assist pathologists in making real-time diagnostic decisions. The figure below presents the step-by-step procedure, demonstrating the clinical application of our diagnostic system . Section title: Workflow for Rapid On-Site diagnosis Educational score: 2.7947380542755127 Domain: biomedical Document type: Other Language: en Fig. 1 Workflow for Rapid On-Site Evaluation (ROSE) of respiratory cytology samples Section title: Model testing Educational score: 4.040510177612305 Domain: biomedical Document type: Study Language: en Images were randomly selected from six categories: 8 images of carcinoid, 5 images of non-small cell carcinoma, 16 images of small cell carcinoma, 33 normal images, 20 images of squamous cell carcinoma, and 34 images of adenocarcinoma. These images were mixed and assigned random numbers. Three cytopathologists, each from a different hospital, along with an AI model, were tasked with diagnosing the individual images. The 116 test images were presented in a multiple-choice format, with the following answer options: precancerous, non-small cell carcinoma, small cell carcinoma, normal, squamous cell carcinoma, and adenocarcinoma. In cases of disagreement between the diagnoses of the physicians and the AI model, the correct diagnosis was selected as the final joint diagnosis. The three diagnosticians included a deputy chief physician with 28 years of experience, an attending physician with 16 years of experience, and a senior resident with 9 years of experience, all from different hospitals. Each of the physicians was qualified in cytological diagnosis. Section title: Combination of AI and cytopathologist diagnoses Educational score: 4.083315849304199 Domain: biomedical Document type: Study Language: en In our study, we adopted a consensus approach to evaluate the combined diagnostic potential of AI and cytopathologists. Each of the 116 digital images was independently assessed by three cytopathologists and the AI model. Final diagnoses were determined based on consensus or specific criteria: a consensus diagnosis was recorded when all four entities agreed; if two or more cytopathologists agreed with the AI’s diagnosis, that was considered final; if the AI’s diagnosis aligned with the most experienced cytopathologist’s (deputy chief physician) diagnosis, it was deemed conclusive; and in cases of disagreement between the AI and cytopathologists, the diagnosis of the most experienced cytopathologist was selected to emphasize the value of human expertise in complex cases. This methodology is utilized for the combined diagnostic accuracy data with the full dataset provided as a supplementary file. Section title: Statistical methods Educational score: 2.2253453731536865 Domain: biomedical Document type: Study Language: en The following diagnostic performance metrics were calculated for each physician and the AI model based on the test data: Section title: Statistical methods Educational score: 3.076683759689331 Domain: biomedical Document type: Other Language: en Sensitivity = TP / (TP + FN) × 100%. Specificity = TN / (TN + FP) × 100%. Positive Predictive Value (PPV) = TP / (TP + FP) × 100%. Negative Predictive Value (NPV) = TN / (TN + FN) × 100%. Accuracy = (TP + TN) / (TP + FN + TN + FP) × 100%. Section title: Statistical methods Educational score: 1.4076721668243408 Domain: other Document type: Other Language: en Where: Section title: Statistical methods Educational score: 2.2044050693511963 Domain: biomedical Document type: Other Language: en TP = True Positive. TN = True Negative. FP = False Positive. FN = False Negative. Section title: Statistical methods Educational score: 3.2890875339508057 Domain: biomedical Document type: Study Language: en Errors were counted as incorrect tumor type predictions or instances where a diagnosis could not be made. Multi-class classification metrics were calculated using the macro-average method, and multi-class ROC curves were generated in Python . Section title: Statistical methods Educational score: 2.154703140258789 Domain: biomedical Document type: Study Language: en Fig. 2 Multi-class ROC curves (macro-average methods) Section title: Results Educational score: 3.9501216411590576 Domain: biomedical Document type: Study Language: en Table 1 presents the diagnostic ability evaluation of the test for the three human doctors and the AI model. The four multi-class ROC curves provide a direct comparison of their respective diagnostic capabilities. Due to the experimental design, evaluating the diagnostic performance of human-AI joint diagnoses is challenging. However, in an ideal scenario where human and AI diagnoses differ, selecting the correct diagnosis would improve accuracy by 4.44%, 13.51%, and 11.79% for each physician, respectively (see Table 2 ). Section title: Results Educational score: 3.921787977218628 Domain: biomedical Document type: Study Language: en Table 1 Statistical results of AI and human cytopathologist interpretation Sensitivity Specificity Positive Predictive Value Negative Predictive Value Accuracy P1% 70.27 92.80 69.84 92.98 88.36 P2% 19.63 86.04 29.72 85.27 77 0.01 P3% 38.21 88.85 40.45 89.18 82.04 AI% 59.95 89.89 52.90 89.40 84.05 Section title: Results Educational score: 2.6775832176208496 Domain: biomedical Document type: Study Language: en Table 2 Improved accuracy of AI-assisted human diagnosis Traditional Method Accuracy Traditional + AI Accuracy Difference P1% 88.38 92.82 + 4.44 P2% 77.01 90.52 + 13.51 P3% 82.04 93.83 + 11.79 Section title: Results Educational score: 4.000007629394531 Domain: biomedical Document type: Study Language: en To further assess the agreement between the AI model and human experts, we computed Pearson correlation coefficients, which are visualized in the correlation heatmap . This heatmap illustrates the correlation between the diagnostic outcomes of the AI model and the three human experts, as well as the combined results of the AI model and each human expert. The color gradient ranges from blue (negative correlation) to red (positive correlation), with white indicating no correlation. The heatmap reveals strong positive correlations across all comparisons, indicating a high level of agreement between the AI model and human experts in their diagnostic assessments. Section title: Results Educational score: 2.3144304752349854 Domain: biomedical Document type: Study Language: en Fig. 3 Pearson correlation heatmap of diagnoses Section title: Results Educational score: 1.8005787134170532 Domain: biomedical Document type: Other Language: en The labels in the heatmap correspond to the following diagnostic methods: Section title: Results Educational score: 2.0975842475891113 Domain: biomedical Document type: Other Language: en Human 1 , Human 2 , Human 3 : Independent diagnostic assessments by three different human experts. AI Result : Diagnostic outcome provided by the AI model. Combined Human 1 , Combined Human 2 , Combined Human 3 : Combined diagnostic outcomes of the AI model with each respective human expert. Section title: Results Educational score: 2.183847665786743 Domain: biomedical Document type: Study Language: en The diagonal line from the top left to the bottom right of the heatmap, colored red, indicates perfect correlation, as each method is compared with itself. This figure underscores the consistency and reliability of the AI model in emulating the diagnostic capabilities of human experts. Section title: Results Educational score: 3.9325218200683594 Domain: biomedical Document type: Study Language: en The heatmap further highlights the strong positive correlations across all comparisons, suggesting a high level of diagnostic consistency between the AI model and the three physicians (P1, P2, P3). Combined results between the AI and each expert show particularly high agreement, underscoring the potential of joint diagnosis to improve overall accuracy. We observed that the AI’s diagnostic performance was comparable to that of human experts, with human accuracy being influenced by years of experience. Therefore, joint diagnosis proved to be significant. Section title: Results Educational score: 1.4009157419204712 Domain: biomedical Document type: Other Language: en (P1 is the deputy chief physician, P2 is the resident physician, and P3 is the attending physician). Section title: Discussion Educational score: 4.021370887756348 Domain: biomedical Document type: Other Language: en The accuracy of cytological diagnosis is heavily influenced by the pathologist’s years of experience, accumulated expertise, and working conditions. It also depends on the adequacy of lesional cell quantity and quality, as well as proper slide preparation. After considering these confounding factors, the cytopathologist makes a holistic judgment based on background, cell arrangement, morphology, size, nuclear features (morphology, size, chromatin quality, nucleoli), nuclear membrane irregularity, N/C ratio, and cytoplasmic characteristics. These principles also apply to rapid on-site cytological diagnosis of respiratory specimens. In clinical practice, cytopathologists strive to differentiate tumor types, but poorly differentiated squamous cell carcinoma and adenocarcinoma often exhibit overlapping morphological features, necessitating immunohistochemical confirmation for definitive categorization. As a result, misclassification between these two types may occur. Section title: Discussion Educational score: 3.9712345600128174 Domain: biomedical Document type: Study Language: en The workflow outlined in this study was specifically designed for the rapid on-site diagnosis of lung cancer, focusing on subtypes such as squamous cell carcinoma, adenocarcinoma, and small cell carcinoma. However, we acknowledge that the principles behind this workflow—such as integrating AI-assisted cytological analysis, real-time diagnostics, and human expertise—could potentially be applied to other lung diseases, including interstitial lung diseases (ILD) and idiopathic pulmonary fibrosis (IPF). While these conditions are distinct from lung cancer, they present unique diagnostic challenges that could benefit from AI support. Section title: Discussion Educational score: 3.9621422290802 Domain: biomedical Document type: Study Language: en It is important to note that the cytological features of ILD and IPF differ significantly from those of malignant lung tumors, requiring potential adaptations in the workflow for accurate diagnosis. At present, the workflow has not been validated for these diseases, and further research is needed to assess its applicability and diagnostic accuracy in non-cancerous conditions. Future studies could explore how the workflow might be adjusted for diseases like ILD or IPF, incorporating disease-specific features while maintaining the diagnostic efficiency of AI and human collaboration. Section title: Discussion Educational score: 4.098683834075928 Domain: biomedical Document type: Study Language: en The suboptimal human diagnosis results in this study can primarily be attributed to the use of Diff-Quik staining for on-site diagnoses. This technique is unfamiliar to most cytopathologists in China, with few pathology labs routinely employing it. Compared to HE or Pap staining, Diff-Quik stains exhibit less nuclear detail and poorer cell cluster contrast, even with microscope adjustments. Thus, improving human on-site diagnosis requires specialized training and experience with this methodology. Additionally, the test provided only one image per question with six answer choices, a setup that differs from real-world conditions. The relatively low physician performance may not accurately reflect their capabilities in routine practice, as pathologists typically examine multiple slides and adjust focus when analyzing suspicious areas. Therefore, single-image testing cannot fully replicate physicians’ true diagnostic proficiency. Section title: Discussion Educational score: 4.199718475341797 Domain: biomedical Document type: Study Language: en ResNet is a deep convolutional neural network architecture originally designed for image classification, and it has been applied to histopathology and cytopathology. Its use for on-site diagnosis of respiratory cytology samples is novel. The improved ResNet-18 model performed exceptionally well in this study. As shown in Table 1 , its diagnostic capability on images reached the level of human experts. Compared to human physicians, the AI model has the advantage of faster processing, taking only about 0.3 s to diagnose each image. Additionally, the AI’s performance is more objective and repeatable. A well-trained AI can detect subtle morphological changes that cytopathologists might overlook, given the considerable subjectivity and poorer reproducibility in human diagnoses (both intra- and inter-observer). For instance, in Fig. 4 , an adenocarcinoma case was missed by all three pathologists because, without control cells as a background, they could not assess the size and shape of the cells properly, potentially overlooking enlarged nucleoli and thickened nuclear membranes. However, the AI identified the case as squamous cell carcinoma, which was closest to the gold standard. In Fig. 5 , the AI correctly identified small cell carcinoma, while the human pathologists either erred or could not provide a definitive diagnosis. Retrospective analysis revealed normal bronchial epithelium in the upper left and a near-naked tumor cell in the lower right, which resembled normal bronchial cells and was easily overlooked by humans. Moreover, while humans can adjust the microscope focus to discern differences in morphology and arrangement, AI faces difficulties in diagnosing complex, high-density cell groups and accurately interpreting cellular arrangements. Advanced algorithms are needed to address these limitations . Section title: Discussion Educational score: 2.2321817874908447 Domain: biomedical Document type: Other Language: it Fig. 4 Adenocarcinoma, x400 magnification, Diff-Quik stain Section title: Discussion Educational score: 2.217106580734253 Domain: biomedical Document type: Other Language: it Fig. 5 Small cell carcinoma, x400 magnification, Diff-Quik stain Section title: Discussion Educational score: 3.7778477668762207 Domain: biomedical Document type: Study Language: en Currently, AI algorithms in cytopathology are still in early development and cannot fully replace human expertise. They may make mistakes or overlook critical cytological features. For example, in Fig. 6 , both the AI and one pathologist called the case normal, while the senior pathologist diagnosed it as non-small cell carcinoma. This discrepancy likely occurred because the cells resembled reactive epithelium, though their nuclear features differed from those of normal cells. Section title: Discussion Educational score: 2.1954610347747803 Domain: biomedical Document type: Other Language: it Fig. 6 Non-small cell carcinoma, x400 magnification, Diff-Quik stain Section title: Discussion Educational score: 3.9194159507751465 Domain: biomedical Document type: Study Language: en AI-assisted diagnosis, where the correct diagnosis is selected when human and AI diagnoses differ, has been shown to improve accuracy, as reflected in the literature . However, human judgment remains essential in clinical practice. When discrepancies arise, professional knowledge and experience are required to assess whether the AI’s conclusion is correct and whether it should be adopted. Ultimately, humans must make the final cytological interpretation . Fully relying on AI also introduces ethical, legal, and governance issues regarding its future application. Nonetheless, AI’s role in cytopathological diagnosis is likely to grow as machine learning and algorithms continue to evolve. Study limitations include using images from only one hospital. To evaluate real-world AI performance, multi-center participation and model training/validation on more cases are necessary to ensure the accuracy and reliability of the models. The ultimate goal is for AI to provide an integrative interpretation of entire digital slides, achieving diagnostic capabilities comparable to cytopathologists. Section title: Discussion Educational score: 4.12542724609375 Domain: biomedical Document type: Study Language: en In our study, we used minimally invasive techniques such as fiber optic bronchoscopy, magnetic navigation bronchoscopy, and CT-guided transthoracic needle aspiration to obtain respiratory cytology samples. These methods are effective in providing diagnostic value while minimizing patient trauma. However, sampling bias, influenced by factors such as lesion location, heterogeneity, and operator experience, may impact the results. While efforts were made to ensure sample diversity and representativeness, the potential for bias remains a concern. Additionally, the morphological differences in tumor samples—such as the distinction between central necrotic areas and peripheral atypical squamous cells in squamous cell carcinoma or the comparison between marginally invasive cells and central mature tumor cells in adenocarcinoma—are significant but beyond the scope of this study. Furthermore, varying case exposure among cytopathologists at different hospital levels directly affects their diagnostic experience, with younger doctors more likely to consider preliminary diagnoses and more experienced doctors considering a wider range of differential diagnoses. Our deep learning model, based on ResNet-18, addresses this experience gap by assisting in diagnostic accuracy, demonstrating its potential to serve doctors across various hospital levels. Moving forward, we plan to expand our research to include a broader range of respiratory diseases, conduct multi-center studies, explore tumor heterogeneity, and optimize the model for better clinical application, ultimately enhancing AI’s role in cytological diagnosis and improving diagnostic services for patients. Section title: Discussion Educational score: 4.046187877655029 Domain: biomedical Document type: Study Language: en While this study focuses on the Chinese context, particularly with the use of Diff-Quik staining, the findings have global relevance. In many resource-constrained settings, including both developing and developed countries, Diff-Quik staining offers a fast, cost-effective, and accessible alternative to more complex staining methods like HE or Pap. In regions where specialized training and advanced diagnostic tools are limited, this simple yet effective staining method can support timely and accurate on-site cytological diagnoses. Moreover, AI-assisted cytology, as demonstrated in this study, holds promise worldwide. While developed countries may have the infrastructure to adopt these technologies, AI can also be instrumental in improving diagnostic capabilities in developing countries, where access to trained pathologists may be limited. The integration of AI into cytopathology could reduce diagnostic variability and enhance the accuracy of diagnoses in diverse healthcare settings. As AI and staining techniques become more accessible globally, these methods could significantly improve diagnostic outcomes, particularly in areas with limited healthcare resources. Section title: Conclusion Educational score: 3.076735496520996 Domain: biomedical Document type: Other Language: en In essence, AI and human cytopathologists form a dynamic partnership that amplifies each other’s strengths. By collaborating, they unlock the potential for improved diagnostic outcomes. AI lightens the workload and boosts diagnostic precision, while human expertise provides critical, high-level judgment, ensuring diagnoses of unmatched accuracy and reliability. Section title: Electronic supplementary material Educational score: 0.9769887328147888 Domain: other Document type: Other Language: en Below is the link to the electronic supplementary material. Section title: Electronic supplementary material Educational score: 1.2997462749481201 Domain: biomedical Document type: Other Language: en Supplementary Material 1 Section title: Electronic supplementary material Educational score: 1.2816039323806763 Domain: biomedical Document type: Other Language: en Supplementary Material 2 Section title: Electronic supplementary material Educational score: 1.2654812335968018 Domain: biomedical Document type: Other Language: en Supplementary Material 3 Section title: Electronic supplementary material Educational score: 1.2187254428863525 Domain: biomedical Document type: Other Language: en Supplementary Material 4 | Review | biomedical | en | 0.999993 |
PMC11697841 | Section title: Conflicts of interest Educational score: 0.8214171528816223 Domain: other Document type: Other Language: it None disclosed. | Other | other | it | 0.857138 |
PMC11697875 | Section title: Background Educational score: 4.057074069976807 Domain: biomedical Document type: Review Language: en A central theme in biology is the idea that function is shaped by structure. Biological tissues, for example, often comprise stereotyped organizations of specific cell types that together enable proper function of the tissue. Formation of these structures during development is orchestrated by intrinsic gene regulatory networks and extrinsic cell-cell interactions. Therefore, analysis of cellular architecture of tissues can provide insight into both developmental processes that generate them and mechanisms that govern their function. Section title: Background Educational score: 4.286152362823486 Domain: biomedical Document type: Review Language: en Recent technological developments in spatial omics have enabled researchers to map the position of cell types in complex tissues . Developing methods to analyze and interpret the resulting cellular maps is an active area of research [ 3 – 5 ]. Reported developments can roughly be classified into three groups. First, methods that examine spatial distribution of one cell type label relative to itself. This includes spatial autocorrelation and Ripley’s spatial statistics that determine whether cells with a given label are clustered, dispersed, or randomly distributed in space. Second, methods that quantify association between pairs of cell type labels based on proximity. Analysis of this kind, which is implemented in popular tools such as and also utilized in several other studies [ 9 – 13 ], can reveal enrichments or depletions in cell-cell interactions by comparing frequency of pairwise interactions in the samples with a random configuration. Third, methods that identify distinct cellular neighborhoods or microenvironments [ 14 – 21 ]. These methods typically cluster cells based on an embedding that represents the types and abundances of their neighboring cells. Variations of this approach have been used to study immune tumor microenvironment in colorectal cancer and reorganization of local tissue architecture in response to acute kidney injury . Methods have also been developed to analyze higher-order assembly of cellular neighborhoods, such as constructing “Tissue Schematics” or to employ concepts from natural language processing, like “bag-of-words” idea in Spatial-LDA, to identify distinct microenvironment “topics” . Section title: Background Educational score: 4.1495490074157715 Domain: biomedical Document type: Study Language: en Despite the remarkable diversity of existing methods for spatial analysis, to our knowledge, none of them capture patterns in sequential arrangement of cells, as they focus on composition of cell types in each region regardless of their order. Spatial ordering of cell types within tissue is crucial for understanding organizational principles. Stereotypical sequential arrangements appear in many tissues, for example in the intestinal crypts along the crypt-villus axis, in airway epithelial cells of bronchioles, and in layers of skin epidermis. But their intricacy and significance is perhaps most evident in the central nervous system, where sequential arrangement of cell types enables precise signal processing and thus is directly related to tissue function. While some simple patterns in the spatial arrangement of cells are readily recognizable, the vast diversity of cell types revealed by spatial omics, combined with the complexity of biological tissues, necessitates a systematic statistical approach to uncover many of the underlying spatial patterns. Section title: Background Educational score: 4.396780014038086 Domain: biomedical Document type: Study Language: en Here, we introduce a strategy for identifying “Spatial Motifs” that reveal statistically overrepresented spatial arrangements in complex tissues. Spatial omics data are often modeled as neighborhood graphs. Our approach focuses on paths in these graphs to directly capture ordered arrangements that may be overlooked by methods focused solely on regional composition. To extend the concept of motifs to spatial maps of cell types, we first developed an algorithm for enumeration and uniform sampling of paths in neighborhood graphs. Each path consists of a sequence of nodes, labeled by the cell types they represent. Paths along which the physical distance monotonically increases capture arrangements of cell types in the sample. Identifying overrepresented patterns in linear sequences, such as DNA, has long been a cornerstone of bioinformatics, with methods extensively refined and optimized over the years. To identify recurring patterns of cell types in sampled paths, we adapted the STREME algorithm, originally developed for motif discovery in nucleic acid sequences, enabling us to build on a history of highly optimized techniques . Our new algorithm, called Spatial MOtif REcognition (SMORE), introduces crucial modifications to accommodate input from spatial graphs rather than one-dimensional sequences. It also integrates motif discovery with differential gene expression analysis to compare cells within spatial motifs to those of the same type located elsewhere in the tissue. Fig. 1 Overview of the spatial motif discovery algorithm. a Schematic of the procedure for finding motifs on a set of spatially distributed nodes, each labeled by a color and a letter for illustration purposes. (1) A set of spatially distributed nodes in 2D space. (2) Delaunay triangularization is used in this case to generate the graph. (3) URPEN is used to sample a set of length-4 radial paths. Control data is created by shuffling the observed graph node cell types. (4) SMORE is used to extract most significant spatial motifs. (5) PWM logos can be used to represent the output motifs. b An example of a radial and a non-radial path. Radial path sampling ensures nodes that are farther from each other in the sample are also farther from each other in physical space. c A simplified example for the SMORE pipeline. Input samples are converted to nmers from length 3 up to length of the motif and p values of the seeds evaluated based on negative binomial test with Bernoulli probability computed based on total number of distinct seeds in primary and control graph. \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\text {nEval}=3$$\end{document} nEval = 3 most significant seeds are input to refine and enrichment where ZNIC p values are used to refine and enrich candidate seeds. Hold-out scoring is performed to compute the p value for the output motif. Nodes of the seeds involved in the motif are erased from the graph and the process is repeated again. More detailed description of each block is provided in the “ Methods ” section. Letters and sequences are chosen for demonstration purposes and do not correspond to specific cell types Section title: Background Educational score: 4.179750442504883 Domain: biomedical Document type: Study Language: en We tested the sensitivity, specificity, and accuracy of SMORE by recovering motifs that were embedded at specified frequencies within synthetic graphs. We then analyzed published datasets of mouse retinal bipolar cells, hypothalamic preoptic region, and embryonic tissue to identify a variety of spatial motifs. Our results revealed that gene expression of cells in some spatial arrangements can differ significantly from other cells of the same type, providing clues to the functional significance of the spatial motifs. We also demonstrate SMORE’s remarkable versatility and scalability by applying it across diverse spatial transcriptomics datasets, spanning both 2D sections and 3D volumes, imaging- and sequencing-based techniques, and a whole mouse brain dataset with nearly 4 million cells. Together, this work presents a novel and broadly applicable approach for identifying patterns in spatial data that go beyond pairwise associations and regional composition. Section title: Design of the spatial motif discovery algorithm Educational score: 4.079329013824463 Domain: biomedical Document type: Study Language: en Our algorithm for finding spatial motifs in neighborhood graphs consists of two main components: first, a method to uniformly sample paths from the graph, and second, a procedure to find motifs in the obtained samples. Each path provides a sequence of cell type labels that occur near each other in space. Generating sequence samples from the neighborhood graphs reduces identification of spatial patterns into finding overrepresented sequences of labels. Despite some important differences, this task is similar to identifying motifs in nucleic acid or protein sequences. Therefore, we generalized existing methods of motif discovery in genomic sequences for our application on graphs. Section title: Design of the spatial motif discovery algorithm Educational score: 3.9672672748565674 Domain: biomedical Document type: Study Language: en The sampling algorithm takes a graph G and returns an unbiased sample of all paths inside the graph. In a graph, a path is a walk that does not intersect itself. Our selected paths are also constrained to be “radial.” Radial condition in a spatially embedded network is defined as the requirement that physical distance along a path monotonically increases along the sequence of edges in the path. Radial condition ensures that the sequence of labels in a sampled path corresponds to a spatial arrangement of cell types in space, so that labels that are farther from each other in the path are also farther from each other in physical distance . Therefore, the radial requirement simplifies interpretation of the output motifs. Section title: Design of the spatial motif discovery algorithm Educational score: 3.681577205657959 Domain: biomedical Document type: Study Language: en After sampling, the motif discovery algorithm identifies sequences of a given length that are statistically overrepresented in an iterative process. In each step, a significant recurring pattern of cell types is identified and is subsequently refined by considering sequences similar to the initial pattern or seed . The algorithms for path sampling and motif discovery are described below. For more details, refer to the extended “ Methods ” section. The time required for analysis of the experimental datasets in this study is summarized in Additional file 1 : Table S1. The code for sampling and motif discovery algorithms is available at: SMORE: Spatial Motif Recognition. Section title: Sampling the graph to generate paths Educational score: 3.695838689804077 Domain: biomedical Document type: Study Language: en The first step in our approach involves uniform sampling of neighborhood graphs. We have developed an algorithm for Uniform Random Path Enumeration (URPEN) based on the Rand-ESU algorithm . The Rand-ESU method involves enumerating all potential subgraphs within a given graph, incorporating a probability element to uniformly sample a subset of these subgraphs. In our modification, we have adapted this method to exclusively sample paths as opposed to subgraphs. Paths differ from subgraphs in that they cannot intersect themselves, and each node, excluding the initial and terminal nodes, is only linked to its preceding and succeeding nodes in the path sequence. This contrasts with subgraphs where nodes can be connected to an arbitrary number of neighboring nodes. This distinction is crucial when selecting the next neighbor to expand the growing sample. Section title: Enumerating all length-k paths in a graph Educational score: 2.595726490020752 Domain: other Document type: Other Language: en The Path Enumeration algorithm (PEN) (Algorithm 1) enumerates all paths of length k within a graph. The algorithm begins with a vertex v from the input graph and adds only those vertices to the set that are neighboring the newly added vertex w but are not already in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V_{path}$$\end{document} V path . To prevent enumeration of both the path and its reverse, for undirected graphs, the index of the last vertex in the enumerated path must be greater than that of v . Section title: Uniform path sampling Educational score: 3.496631383895874 Domain: other Document type: Study Language: en Similar to ESU-tree, the PEN algorithm’s structure can be visualized as a tree structure. The tree structure for an example graph is demonstrated in . This tree has 18 leaves which correspond to the 18 size-3 paths of the graph. We can use this tree to sample paths uniformly without bias. The PEN algorithm systematically traverses its associated PEN-tree. In situations where a full traversal is impractical, we can perform a partial exploration of the PEN-tree such that each leaf is reached with equal probability. To achieve this, a probability is introduced for each depth \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$1 \le d \le k$$\end{document} 1 ≤ d ≤ k in the path (or each depth in the PEN-tree), and the subsequent node rooted at a node at depth d is traversed with probability \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p_d$$\end{document} p d . This is implemented by calling the ExtendPath function at lines 3 and E6 of the PEN algorithm (Algorithm 1) with probability \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p_d$$\end{document} p d . This new algorithm is called Uniform Random Path Enumeration, URPEN. It can be observed that URPEN visits each path with equal probability of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p =\prod _{d=1}^k p_d$$\end{document} p = ∏ d = 1 k p d . The method is tested in the “ URPEN enables efficient and unbiased sampling of neighborhood graphs ” section on a random graph to validate its accuracy numerically. Fig. 2 Unbiased sampling of paths from neighborhood graphs. a An example of the PEN sampling tree. b URPEN returns each path at a frequency corresponding with the sampling level, whereas Radial Random Walk (RRW) results in biased sampling of the graph. Examples of RRW upsampled and downsampled paths are shown in the top right corner of the 20% sampling panel. The sampling probability in URPEN is set to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p=(1, 1, \ldots , 1, 0.2)$$\end{document} p = ( 1 , 1 , … , 1 , 0.2 ) for 20% sampling, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p=(1, 1, \ldots , 1, 0.6)$$\end{document} p = ( 1 , 1 , … , 1 , 0.6 ) for 60% sampling. This test was performed 1000 times. c Sampling quality with URPEN and RRW on the bipolar cell type graph and a random graph with 12000 nodes. d Sampling speed for non-radial and radial sampling on the bipolar and random networks Section title: Spatial MOtif REcognition (SMORE) Educational score: 4.246903896331787 Domain: biomedical Document type: Study Language: en Applied to a neighborhood graph, URPEN returns sequences of cell types that are observed near each other. Similar to DNA sequences, we can search through these cell type sequences for motifs using unsupervised learning techniques. The SMORE method is developed to detect motifs within the sampled sequences. Our approach uses as its basis the recently developed STREME method which the author has demonstrated to be more accurate, sensitive, and comprehensive than several widely used motif discovery algorithms. STREME is developed to find motifs within sequence-like samples; SMORE on the other hand finds motifs in a network-based dataset. The algorithm follows a series of steps to accomplish its objectives. Construct the graph from spatial data: To construct a graph from the spatial coordinates of cell types, Delaunay triangularization is employed, forming a graph with nodes as cells, labeled with their respective cell types. Given that each dataset may comprise multiple tissue sections or animal IDs, separate graphs are generated for distinct sections and IDs. For generating control data, each section or animal ID is shuffled independently. Additionally, besides Delaunay triangularization, the method offers options to construct the graph using arbitrary K nearest neighbors or epsilon graph approaches. Sampling the graph and generating control data: SMORE uses URPEN for uniform sampling of the input graph. Control samples are generated using one of two methods: shuffle or kernel. The shuffle method produces control data by shuffling node cell type labels within samples (e.g., tissue sections and animal IDs). On the other hand, the “kernel” method establishes a kernel around each cell and swaps the cell’s label with that of a cell within its kernel . In the experiments detailed in this paper, kernels with a radius of K neighbors are used, where K is specified for each experiment. K = 1 means only first neighbors within the graph are considered for shuffling. The degree of randomness in the control data is controlled by adjusting the number of neighbors considered for shuffling. There are certain scenarios where specific cell types associated motifs are readily apparent. In such cases, these cells can be fixed between primary and control data, meaning that their cell labels are not shuffled. We generate nTrain control data and seed numbers for control data are the total number of that specific seed within these nTrain samples. NScore independent control data is generated for output motif scoring, with the same settings as the training data. Convert to n-mers and count seeds: Input samples to the algorithm can be of an arbitrary length. These samples are converted to W-mers, where W is the desired motif length. These W-mers are input to the count seed modules. Three strategies have been proposed for counting motif instances: counting all occurrences, counting those with no shared edges, and counting those with no shared nodes . We adopted the third approach, which assumes that motifs share no common nodes, to prevent overrepresentation due to overlapping occurrences. This approach, referred to here as the Zero Node in Common (ZNIC) model ensures that each counted motif instance is structurally independent. Motif counts under ZNIC model are referred to as ZNIC counts. By using the ZNIC model, we avoid inflated frequency counts, allowing for a more accurate capture of the network’s true structural patterns. ZNIC counts of unique seeds, along with their associated nodes, are then passed to the next module for evaluating initial seeds. Initial seed evaluation: The significance of each initial seed is obtained by the negative binomial test (see the “ Methods ” section for details). The justification for this specific test is argued in the extended “ Methods ” section. The first nEval seeds with this criterion are passed to the next stage of refinement and enrichment. The default value for nEval is 25. Refinement and nested seed enrichment: The refinement and seed enrichment both use the same process of enrichment, except that refinement is only one iteration, and seed enrichment is nEnrich iterations, with the default value of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\text {nEnrich}=20$$\end{document} nEnrich = 20 . Enrichment groups similar path samples together and compares ZNIC counts of the grouped sequences with the control data. nEval motifs from the initial evaluation step are first enriched for one iteration and top nRef (nRef = 4 as a default) motifs are further refined in seed enrichment block for nEnrich iterations or until p value does not improve. During each iteration, the Position Weight Matrix (PWM) is calculated from the sequences participating in the motif. Likelihood ratio scores are then computed for all samples, using this PWM matrix, and the samples are arranged in descending order based on their PWM scores. In the event of an equal PWM score, the samples are further sorted based on their p values obtained in the initial evaluation block. Subsequently, ZNIC counts for the ordered samples are determined, and the PWM score threshold that minimizes the p value is identified. This process is iterated if the p value obtained is more significant than the previous iteration. Motif scoring: In most cases, tissue samples are different from each other and it is not optimal to take sections of the samples as hold-out for scoring. In our experiment, the same samples are used for finding motifs and scoring the output motif, with the scoring part iterated over NScore times with different shuffled networks to avoid false positives. Implementation results on synthetic data with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\text {nScore}=50$$\end{document} nScore = 50 shows that the false positive rate is negligible. Furthermore, tests on real data with randomly shuffled cell type labels did not result in any significant output motif. The ZNIC counts for the seeds involved in the output motif are computed in the primary and nScore randomly generated control data and the 95 percentile least significant p value is considered as the output p value of the scoring module. Motif node erasing: The respective nodes for the seeds involved in the motif are erased (i.e., their cell type is set to 0) from the graph in primary and control data along with their reverses. The previous steps are then repeated until output motifs are not significant anymore, or a specified number of output motifs have been discovered. Section title: URPEN enables efficient and unbiased sampling of neighborhood graphs Educational score: 3.544837713241577 Domain: biomedical Document type: Other Language: en The sequence of cell types along a path in the neighborhood graph captures their local spatial arrangement. A collection of these sequences can be used for identifying overrepresented patterns in the graph, only if it represents an unbiased sample of all possible paths. Furthermore, the sampling algorithm should be able to handle the large number of cells in typical spatial transcriptomics datasets. Section title: URPEN enables efficient and unbiased sampling of neighborhood graphs Educational score: 3.863621950149536 Domain: biomedical Document type: Study Language: en To confirm that URPEN sampling is unbiased, we generated a graph by applying Delaunay triangularization on a spatially uniform distribution of 120 two-dimensional Cartesian points. We then used URPEN to sample radial paths of length 5 from this random graph at three sampling levels; 20%, 60%, and 100%. If sampling is unbiased, we expect each path to appear in the sample with a probability equal to the sampling level. We repeated these tests 1000 times. So, for the case of 20% sampling, we expect each path to appear on average 200 times in the output results. This number is 600 for 60% sampling and 1000 for complete 100% sampling. As a comparison, we also sampled the same graph with the commonly used random walk method. Random walk starts with a randomly chosen node and subsequent nodes are selected from the neighboring nodes with equal probability, until a path of the desired length is obtained. Section title: URPEN enables efficient and unbiased sampling of neighborhood graphs Educational score: 3.394200563430786 Domain: biomedical Document type: Study Language: en While URPEN returned paths at the expected frequency, random walk sampling showed significant bias for certain paths . The distribution of the URPEN counts is also consistent with a set of identical independent binomial distributions with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p = p_d$$\end{document} p = p d , confirming that paths were sampled with equal probability . Similar results were obtained for other path lengths and for paths not constrained by the radial condition . The sampling bias of random walk can be mitigated by using unbiased estimators . However, that incurs complexity and leads to a penalty in speed performance . Section title: URPEN enables efficient and unbiased sampling of neighborhood graphs Educational score: 4.107772350311279 Domain: biomedical Document type: Study Language: en We also evaluated the sampling quality of URPEN compared to random walk . Sampling quality is defined as the percentage of path types for which the number of extracted paths has at most 20% error relative to the exact counts, similar to the measure used previously . Path samples with at least 5 counts were considered for quality evaluation. Sampling quality was computed for two cases: A random graph with 12,000 nodes and 35,823 edges and a graph based on spatial distribution of bipolar cells in a section of mouse retina . Sampling quality for the URPEN method increases with increasing sampling probability, reaching one at complete sampling. In contrast, sampling quality for the random walk peaks at around 0.5. Section title: URPEN enables efficient and unbiased sampling of neighborhood graphs Educational score: 3.77205228805542 Domain: biomedical Document type: Study Language: en We then assessed how sampling speed scales with the path length . The two graphs of Fig. 2 c was sampled by URPEN at 10% level. The speed appeared to be independent of the path length for non-radial paths. However, when the radial constraint was applied, the speed decreased with path length, because the proportion of paths that meet the radial condition decreases with increasing path length. Consistent with this explanation, the speed of sampling radial paths is not independent of graph architecture, as it appears to be the case for the non-radial paths. Together, our results demonstrate that URPEN avoids the shortcomings of random walk sampling and offers a robust method for uniform path sampling. Section title: SMORE accurately identifies overrepresented cell type arrangements in synthetic graphs Educational score: 4.116283416748047 Domain: biomedical Document type: Study Language: en Evaluating the performance of SMORE requires datasets with known ground truth. Since the presence and frequency of overrepresented spatial patterns in existing experimental data is unknown, we created synthetic data by embedding patterns within random graphs at known frequencies. Each graph has 12,000 nodes, 35,823 edges, and 12 cell types. The embedding percentage indicates the proportion of nodes used for pattern embedding. For example, 2% embedding indicates that 2% of the nodes (i.e., 240 nodes) were used for embedding patterns. In the case of a length 4 motif, this results in 60 sequence patterns. Other nodes in the graph were labeled randomly. Embedded patterns included one variable position, which was filled with one of two cell types with equal probability. Other positions in the pattern were assigned one predefined cell type. Although more complex patterns can also be considered, we chose our patterns so that they are sufficiently complex while still providing insight into the algorithm’s performance. The algorithm was run 100 times for each embedding frequency, generating 10 output motifs per run. The samples for length 4 motif included all possible radial paths inside the graph. For the length 5 motif, the graph was downsampled by URPEN and 65% of all radial paths were used. Section title: SMORE accurately identifies overrepresented cell type arrangements in synthetic graphs Educational score: 4.124412536621094 Domain: biomedical Document type: Study Language: en The accuracy of a motif discovery algorithm describes its ability to recover accurate versions of overrepresented patterns . We assessed the accuracy of SMORE by measuring the similarity of output motifs to embedded patterns . In each run, SMORE returns 10 motifs that are sorted based on their statistical significance. At embedding frequencies above 0.5%, the most significant output motif tends to be the one most highly correlated with the embedded pattern. At 1% and higher embedding frequency, the Pearson correlation coefficient between the extracted motifs and the embedded patterns was higher than 0.9 in all 100 tests. Based on these results, we expect SMORE to be able to accurately identify length 4 and 5 motifs even when they only occur at low frequencies in a sample. Fig. 3 Evaluation of SMORE’s performance on synthetic data with known ground truth. a Accuracy of SMORE, defined as the best correlation coefficient between the embedded motif and extracted motifs for length 4 motifs with varying embedding frequency ( f ). This figure represents the average results from 100 algorithm runs. The highlighted curves indicate the best correlation among the n = 10 output results. Faded curves demonstrate the results when considering only n = 1, 2, or 3 of the best output motifs, instead of all 10. Examples of motifs with different levels of correlation are shown on the top. b Specificity results for length 4 motifs, measured by false positive rate and true positive rates against log p value threshold and ( c ) against each other. d Sensitivity of SMORE measured by successful motif recovery rate against embedding frequency and ( e ) enrichment log p value Section title: SMORE accurately identifies overrepresented cell type arrangements in synthetic graphs Educational score: 4.108880043029785 Domain: biomedical Document type: Study Language: en To assess the specificity of SMORE, we examined the true positive rate (TPR) and false positive rate (FPR) against output p values (see the “ Methods ” section for details). Ideally, both TPR and FPR should be high at high p values and decrease as the p values decrease, with FPR decreasing at a faster rate to allow for correct motif identification. Accordingly, we observed that FPR curves reached zeros at around log p value of –10, while TPR performance gradually increases with the embedding frequency . The corresponding ROC curves confirm close to perfect classification performance of SMORE at embedding frequencies higher than 1%. Section title: SMORE accurately identifies overrepresented cell type arrangements in synthetic graphs Educational score: 4.09303092956543 Domain: biomedical Document type: Study Language: en To evaluate the sensitivity of SMORE, we defined success rate to be the proportion of output motifs that are statistically significant, at a given p value, and have a Pearson correlation coefficient of at least 0.95 with respect to the embedded pattern. With a log p value threshold of –10 , success rate for identifying length 5 motifs exceeds 90% at embedding frequencies above 1%. Success rates for length 4 motifs increase more gradually with embedding frequency, exceeding 90% only at 3% embedding. At each embedding frequency, success rate appeared to drop sharply beyond a specific p value threshold . As expected, this threshold decreases with increasing embedding frequency. Section title: SMORE reveals spatial motifs in the distribution of mouse retinal bipolar cells Educational score: 3.962805986404419 Domain: biomedical Document type: Study Language: en Retina contains a rich diversity of neuronal cell types, organized into three layers of cell bodies. These cell types have different features and frequencies and are tiled across the retina in a stereotypical manner that supports the overall function of the tissue. Cell type diversity and individual variability make it difficult to identify recurring patterns in the cellular architecture of the retina. Spatial motif analysis can reveal higher order associations between retinal neurons and provide insight into their development and wiring. Section title: SMORE reveals spatial motifs in the distribution of mouse retinal bipolar cells Educational score: 4.163466930389404 Domain: biomedical Document type: Study Language: en We applied SMORE on a dataset of the mouse bipolar interneuron subtypes containing more than 30,000 cells . These subtypes were differentiated using co-detection of 16 gene markers by SABER-FISH, allowing the classification of all 15 bipolar subtypes. Bipolar interneurons bridge all visual circuits, establishing the link between sensory rod and cone photoreceptors and the output neurons. Bipolar cells also do not migrate from their birthplace, providing a spatial map between their final location and the location of their progenitors . Section title: SMORE reveals spatial motifs in the distribution of mouse retinal bipolar cells Educational score: 4.30640172958374 Domain: biomedical Document type: Study Language: en Rod bipolar cells (RBCs) constitute the majority of retinal bipolar cells in mice and their cell bodies are mainly organized together, further out in the inner nuclear layer (INL) compared to cone bipolar cells (CBCs) . SMORE evaluates the statistical significance of cell type arrangements in the experimental data against control data, which are generated by shuffling cell type labels. When shuffling is done for all cells across the whole graph, relatively obvious structures, like separation of RBCs, are identified as highly significant motifs . To reveal other motifs involving RBCs, besides this trivial case, we can fix the position of RBCs in the control data . This would eliminate any motif whose significance stems from RBCs and elucidate the relationship between RBCs and other cell types . Fig. 4 Spatial motif analysis of mouse retinal bipolar cells. a A retinal section with classified bipolar subtypes (left) and examples of control data generated from this section using different randomization methods, global shuffling (middle) and shuffling with fixed RBCs (right). b The top five output motifs, identified using the global shuffling method, are displayed in order from top to bottom with their respective log p -values. Their positions within a section of the retina are shown by highlighting the nodes associated with each motif, using the color code in the bottom right corner. Two example regions, marked by rectangles, are enlarged for a closer view. c Same as b , but for motifs obtained when RBCs are fixed. Annotations for the cell types involved in the motifs are listed at the bottom. d Schematic for primary pathway for rod-driven signals involving rods, rod bipolar cells, AII amacrine cells, OFF or ON (cone) bipolar cells, and OFF or ON ganglion cells. e Absolute log p value versus difference in gene expression medians (delta median) for cells in a spatial motif versus cells of the same type that are not in a motif arrangement. The results for a random selection of cells are shown in red. f Selected cases and genes with absolute log p value greater than 7. The heatmap is colored with delta median values. The motif cases, specified by motif number-position-cell type, are sorted by cell type on the vertical axis. Values in each cell show absolute log p value for comparison between cells within a given motif and overall cells of the same type Section title: SMORE reveals spatial motifs in the distribution of mouse retinal bipolar cells Educational score: 4.538468837738037 Domain: biomedical Document type: Study Language: en Our analysis revealed several highly significant spatial motifs among retinal bipolar cells. These motifs can be investigated in the context of retina development, anatomy, and physiology. For example, when RBC positions are fixed, the most significant motif involves a type 2 OFF CBC followed by two RBCs and a type 6 ON CBC . Overrepresentation of this cellular arrangement can be understood in the context of a primary rod pathway that enables scotopic vision . Within this pathway, the signal originating from a single rod cell is primarily directed to a select few AII amacrine cells through two RBCs . The AII amacrine cells establish connections with nearly all bipolar cell types to gather scotopic signals originating from RBCs (denoted as O in our motif notation). These signals are then distributed to both ON and OFF CBCs through gap junctions and inhibitory synapses, respectively . However, the number of connections varies depending on the bipolar cell types . Type 2 (C) cells account for 69% of the total number of OFF bipolar chemical synaptic contacts with AII amacrine cells, while type 6 (K) cells contribute 46% of the total area of ON bipolar gap junctions with AII amacrine cells . Both type 2 and type 6 cells not only have the highest access to AII amacrine cell signals but also share these signals with other types of bipolar cells through interconnected gap junctions in the network. These findings support the central role of type 2 and type 6 cells in conveying the most sensitive scotopic signals to the postsynaptic ganglion cells. Furthermore, AII amacrine cells are characterized by their narrow-field dendrites. Typically, a bipolar cell receives more inputs from AII amacrine cells that are in its close proximity . This suggests that bipolar cell types involved in scotopic vision should be spatially close to each other. Given these considerations, we hypothesize that the COOK motif is associated with the primary rod pathway for scotopic vision in mice. Section title: SMORE reveals spatial motifs in the distribution of mouse retinal bipolar cells Educational score: 3.7742085456848145 Domain: biomedical Document type: Study Language: en SMORE is specifically designed to identify overrepresented sequential arrangements of cell types. Therefore, its objective and output differs from previous methods that search for spatial neighborhoods or microenvironments based on local cell type composition, regardless of order of cells. To clarify this distinction, a side-by-side comparison between SMORE and two such methods, HistoCAT and ImaCytE , is included in the Supplementary Information . Section title: Cells within spatial motifs exhibit gene expression differences compared to other cells of the same type Educational score: 4.12606954574585 Domain: biomedical Document type: Study Language: en Spatial context of the cells often influences their function. With recent advances in spatial gene expression profiling, there has been an increased interest in systematically characterizing spatial variability of gene expression [ 32 – 38 ]. Spatially variable genes may explain functional distinctions between cells in different regions or demarcate spatial domains [ 32 – 34 , 37 ]. If spatial motifs represent functional units made of various cell types that together play a distinct role, we can expect cases with distinct gene expression signatures. Specifically, cells within some spatial motifs may exhibit unique gene expression profiles compared to cells of the same type that lie outside these specific spatial arrangements. Section title: Cells within spatial motifs exhibit gene expression differences compared to other cells of the same type Educational score: 4.11948823928833 Domain: biomedical Document type: Study Language: en We assessed differential gene expression between cells of each type that are involved in a spatial motif and the ones that are not. For each gene, the median expression value among the cells of a specific type that are involved in the motif was subtracted from the median of all the cells of the same type. The p values for the observed delta medians were obtained through theoretical computation by analyzing the distribution of delta median values for a random subset of cells (see the “ Methods ” section for details). We performed this analysis for motifs obtained by shuffling with fixed RBC cells for the 16 genes profiled in the retinal bipolar dataset . Several cases of highly significant differential gene expression were observed in the motif cells . In contrast, control samples where a random subset of cells were selected, with the same size and type of the corresponding motif case, showed much higher p values. This observation is consistent with functional specialization of cells in spatial motifs. Section title: Cells within spatial motifs exhibit gene expression differences compared to other cells of the same type Educational score: 3.9763152599334717 Domain: biomedical Document type: Study Language: en The heatmap in Fig. 4 f illustrates the absolute log p values across all cases for 20 output motifs. Each motif can consist of multiple cell types in different positions. For example, the second motif in the fixed shuffling case of Fig. 4 c comprises 10 cells, 4 cells in each of the positions 1 and 4, and one cell in positions 2 and 3. Here, we consider each cell type in each position of each motif as a separate case. Genes with absolute log p values greater than 7 are highlighted in Fig. 4 f. Section title: Cells within spatial motifs exhibit gene expression differences compared to other cells of the same type Educational score: 4.485057830810547 Domain: biomedical Document type: Study Language: en Among genes that were significantly upregulated or downregulated in the motifs, Grm6 stands out because it shows the most extreme differential expression in both directions. Grm6 is upregulated in type 1b OFF bipolar cells (B) in OBBO motif, where O represents an RBC, ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\text{delta}\;\text{median}=45,-\log(p\text{value})=30.31$$\end{document} delta median = 45 , - log ( p value ) = 30.31 ) and downregulated in type 5b ON bipolar cells (H) in HBBI motif ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\text {Delta} \; \text {median} = -12, -\log (p\text{value}) = 14.67$$\end{document} Delta median = - 12 , - log ( p value ) = 14.67 ). Grm6 encodes the metabotropic glutamate receptor 6 (mGluR6) which is localized to the dendritic tips of ON bipolar cells . It plays a crucial role in triggering depolarization of ON bipolar cells in response to light-induced hyperpolarization of photoreceptors . Mutations in Grm6 gene in humans lead to autosomal recessive congenital stationary night blindness (arCSNB) . Section title: Cells within spatial motifs exhibit gene expression differences compared to other cells of the same type Educational score: 4.255061149597168 Domain: biomedical Document type: Study Language: en We observed that enrichment of Grm6 in type 1b cells in motif 11 (OBBO) can be explained by their position along the radial axis of the retina. Grm6 is expressed at higher levels in type 1b cells whose cell body is closer to the photoreceptor level . Since RBCs (O) are concentrated in this outer region, type 1b cells in OBBO motif also tend to be in radial positions where Grm6 expression is higher . In contrast, downregulation of Grm6 in type 5b cells (H) of motif 4 (HBBI) seems to be explained by their proximity to type 1b (B) cells rather than their radial position . Type 1b cells lack dendrites connecting them to photoreceptors . Therefore, the mechanism of their function is not well understood . Our observation suggests that type 1b cells may influence signal processing in the retina by altering expression of key postsynaptic receptors, like Grm6, in nearby ON bipolar cells. Fig. 5 Grm6 shows motif specific expression patterns. Expression of Grm6 versus radial position of cell in the mouse retina for ( a ) type 1b and ( b – d ) 5b cells. Cells within specific spatial arrangements are highlighted in each panel. The radial position was computed by considering the outer extreme points as the maximum radius points and computing the radial position for other nodes relative to the nearest outer point Section title: SMORE reveals overrepresented cell type arrangements in the preoptic area of mouse hypothalamus Educational score: 3.9768807888031006 Domain: biomedical Document type: Study Language: en To explore the utility of SMORE at identifying non-trivial recurring patterns in a significantly more complex sample, we applied it to a spatial transcriptomics dataset of the mouse hypothalamic preoptic region . This dataset profiles about 1 million cells and has identified about 70 neuronal populations with distinct signatures and spatial organizations. Section title: SMORE reveals overrepresented cell type arrangements in the preoptic area of mouse hypothalamus Educational score: 4.19357967376709 Domain: biomedical Document type: Study Language: en As we showed before, the approach used to generate control data affects the output motifs. This can be used to tune the algorithm to different anatomical features. Here in addition to fixing specific cell types, we introduce local kernel shuffling . Shuffling cell labels across the entire sample can result in the emergence of relatively straightforward structural motifs, such as regional boundaries. On the other hand, local shuffling maintains cell type frequencies within cellular neighborhoods. Therefore, if a sample is compartmentalized to regions with distinct cellular compositions, local shuffling is more likely to identify patterns that are overrepresented within each compartment. Control data generated by local shuffling maintains a higher degree of similarity with respect to the original experimental data. Therefore, the motifs obtained with global shuffling tend to have more significant p values compared to the output motifs of local shuffling. In both shuffling methods, if certain cell types form obvious structures (e.g., Fig. 6 a Ependymal cells (blue)), their positions can be fixed in the control data. Fig. 6 Spatial motif analysis of mouse hypothalamic preoptic region. a The graph of the preoptic region of the hypothalamus from five adult male mouse brains at Bregma − 0.29. b Examples of control data generated from the 5th tissue using different randomization methods: global shuffling, kernel shuffling with 6 neighborhood depth, and kernel shuffling with 4 neighborhood depth. c Control data obtained by applying the same randomization methods as ( b ) but with the positions of non-neuronal cell types fixed. d The top five motifs, identified using global shuffling (top), kernel shuffling with depth 6 (middle), and kernel shuffling with depth 4 (bottom). The position of motifs within a tissue section is shown to the right, along with their log p -value, ordered from top to bottom. To show the position of the motifs, nodes associated with each motif are highlighted using the color code in the bottom right corner. e Same as d , but for motifs obtained when non-neuronal cell types are fixed. Annotations for the cell types involved in the motifs are listed at the bottom Section title: SMORE reveals overrepresented cell type arrangements in the preoptic area of mouse hypothalamus Educational score: 4.128572463989258 Domain: biomedical Document type: Study Language: en We applied SMORE to cellular maps of the hypothalamus preoptic region from five adult male mouse brains at Bregma − 0.29 to identify length 4 spatial motifs. The sections used in our analysis comprise 28,866 cells. We tried both global shuffling and local shuffling with kernel sizes of 4 and 6 . In another set of experiments, we also fixed the position of non-neuronal cell types between the primary and control data . When non-neuronal cell types were not fixed, the most significant motif consists of a group of four interconnected ependymal cells . This pattern is immediately visible in the graphs because ependymal cells form a layer that lines the ventricles. As expected, fixing the position of non-neuronal cells removes this motif as well as the motif made entirely of mature oligodendrocytes . Instead, other motifs emerge, some of which are combinations of ependymal and neuronal cells (e.g., motif 3 of fixed global shuffling). Section title: SMORE reveals overrepresented cell type arrangements in the preoptic area of mouse hypothalamus Educational score: 4.20098876953125 Domain: biomedical Document type: Study Language: en The first five motifs generated through the global shuffling method correspond to discernible patterns within the fifth tissue section shown in Fig. 6 a. In addition to the first motif of ependymal cells, motif 2 comprises astrocytes, E-9, and E-14 cell types, which are enriched in the PVA nuclei of the hypothalamus . E-14 and E-9 cells also show similar gene expression patterns . Motif 3 represents a pattern of mature oligodendrocytes known to be enriched in the anterior commissure and the fornix. Motif 4 is a pattern of I-2 and I-13 cells which are indicated to be enriched in BNST-p and StHy nuclei. I-2 and I-13 are both aromatase-enriched clusters and express both androgen receptor (Ar) and estrogen receptor alpha (Esr1) . Motif 5 is primarily composed of cell types I-11, I-12, and I-14, collectively enriched in the MPN and StHy nuclei. Section title: SMORE reveals overrepresented cell type arrangements in the preoptic area of mouse hypothalamus Educational score: 4.088557243347168 Domain: biomedical Document type: Study Language: en Motifs obtained from kernel shuffling methods capture less obvious patterns. For instance, motif 5 in the case of “fixed kernel 6,” represented as hSci sequence which is equivalent to a radial path of 4 excitatory neuronal cell types, E-15, E-8, E-12, and E-17, occurs 4 times in the primary data (2 occurrences in each of animal IDs, 10, and 11) and 3 times in the total of 50 generated control data. This motif consistently appears in kernel shuffled tests, with different ranks. Interestingly, there is a similar motif, BSic, with B representing astrocytes, that appears as motif 11 of the not fixed kernel 4 experiment and appears at the opposite side of the brains of the same Animal IDs. Section title: SMORE reveals overrepresented cell type arrangements in the preoptic area of mouse hypothalamus Educational score: 4.201672077178955 Domain: biomedical Document type: Study Language: en The functional explanation of identified spatial motifs is not the focus of this study. But it is reasonable to expect that such patterns hint to either functional relationships between the cell types involved or specific developmental programs that generate them. Therefore, they can help generate hypotheses for future studies. For instance, motif 5 in the non-fixed global shuffling experiment primarily consists of cell types I-11, I-12, and I-14. In the case of the fixed shuffle, motif 4 is predominantly composed of cell types E-8, E-15, I-34, and I-15 in the first position, while I-11 occupies the remaining positions. I-15, I-2, I-11, I-14, I-33, E-8, and E-15 cells display sexually dimorphic cFos enrichment in male mating . Interestingly, a similar motif exists in female sections , where I-15 replaces I-11. The Esr1-enriched cluster I-15 exhibits significant enrichment in female animals and is preferentially activated in females, with lesser activation in males after mating . Section title: SMORE reveals overrepresented cell type arrangements in the preoptic area of mouse hypothalamus Educational score: 4.1905975341796875 Domain: biomedical Document type: Study Language: en We also performed gene expression analysis for the motifs obtained by global shuffling with fixed non-neuronal cells. Many cases of highly significant differential gene expression were observed in the motif cells . The heatmap in Fig. 7 b illustrates the absolute log p values across all cases for 40 output motifs. The majority of statistically significant cases for genes imaged using combinatorial smFISH measurements are concentrated in the first 10 output motifs. In contrast, genes measured through sequential FISH rounds, typically genes with higher expression levels, exhibit a higher prevalence of significant cases in this analysis. This difference is probably related to the fact that gene expression values for sequential genes are generally under dispersed , resulting in the upregulated or down regulated genes being more significant. Genes with absolute log p values greater than 20 are highlighted in Fig. 7 c. In most cases, the significance of differential gene expression varies depending on the position in the motif. For example, Vgf is upregulated in motif 2, position 1, cell type 26 (i.e., 2-1-26 case). But its differential expression is not significant in position 3 of the same motif. This may indicate that within a spatial motif, cells of the same type in different positions can have differences in their gene expression and potentially distinct roles. Fig. 7 Motif specific gene expression analysis for hypothalamus motifs. a Absolute log p value against difference in median gene expression in motif and non-motif cells. Blue markers show experimental results; red markers are the results for one random selection of cells. The expression values are not normalized. b Heatmap of absolute log p values for genes (on the horizontal axis) and motif cases (on the vertical axis). Out of 155 genes, 135 were measured by combinatorial FISH and 20 were measured in sequential rounds of FISH. These two groups are separated with a dashed line. c Selected cases and genes with at least one absolute log p value greater than 20. The motif cases are sorted by cell type. The gene names and their motif address (motif number-position-cell type) are included on the x - and y -axis, respectively Section title: Identifying spatial motifs in a 3D sample Educational score: 4.192682266235352 Domain: biomedical Document type: Study Language: en So far, spatial transcriptomics has mostly been applied to thin tissue sections or monolayer cultured cells. In these cases, obtained measurements are typically projected on a two-dimensional plane. However, recent advances have made it possible to map gene expression in thicker tissue slices, resulting in 3D datasets [ 45 – 48 ]. This is an important step in development of spatial methods because it enables profiling of cells in their native context, which in many tissues of interest is inherently three-dimensional. Since our method operates on a neighborhood graph, it should be able to identify spatial motifs in 3D datasets as well. To test this, we applied SMORE on the cellular map of a 200-µm-thick slice of mouse anterior hypothalamus, encompassing over 78,000 cells . The cells in this dataset are classified into 21 excitatory neuronal clusters, 26 inhibitory neuronal clusters, and 7 non-neuronal cell subclasses based on the expression of 156 genes . Fig. 8 Spatial motif analysis of a 200 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\upmu$$\end{document} μ m slice of mouse hypothalamus. a The graph of 3D MERFISH dataset with classified cell subtypes shown as dots colored by subtype. The perpendicular views from different angles are shown alongside the 3D view for the primary graph. Epen, ependymal cells; ASC, astrocytes; OGC, oligodendrocytes. Excitatory and inhibitory subtypes started with E and I letter, respectively. b The first 20 spatial motifs obtained using global shuffling to generate the control data. c The first 5 output motifs along with their highlighted nodes on the tissue graph, and their respective log p values. Annotations are the same as Fig. 6 for the shared cell types Section title: Identifying spatial motifs in a 3D sample Educational score: 3.8298981189727783 Domain: biomedical Document type: Study Language: en Figure 8 b illustrates the top 20 output motif nodes highlighted within the graph. Comparing this figure with the equivalent view from Fig. 8 a (lower left) indicates the similarity of the highlighted motifs with the visual structure of tissue and agrees with our expectation that global shuffling is able to derive discernable patterns, along with other motifs that are less obvious. Figure 8 c highlights the first 5 motifs along with the logos representing the identified motifs. Overall, our results demonstrate that SMORE can be used for analysis of both 2D and 3D spatial data. Section title: Identifying spatial motifs in a 3D sample Educational score: 4.141200065612793 Domain: biomedical Document type: Study Language: en The cells within the 3D graph of tissue structure tend to have a greater number of neighbors on average compared to those in 2D datasets. For instance, while the average number of neighbors for the 2D mouse hypothalamus dataset in Fig. 6 a is 5.9, it is 15.2 for the 3D hypothalamus dataset. Additionally, the 3D dataset comprises more than twice the number of cells in the 2D hypothalamus dataset (78,229 compared to 28,866). Consequently, the number of paths within the 3D dataset is substantially higher. Here, we used URPEN to sample 10% of the radial paths in this 3D tissue graph. Despite this downsampling, the number of radial paths for the 3D dataset was 1,838,093, while it was 696,141 for the specific tissue sections analyzed in Fig. 6 , which were not downsampled. Due to the larger sample size, the log p values for the 3D dataset exhibit greater significance. Section title: Identifying spatial motifs in a 3D sample Educational score: 3.736651659011841 Domain: biomedical Document type: Study Language: en To further demonstrate scalability of our approach, we applied SMORE on a spatial atlas of the whole mouse brain (Allen Brain Cell Atlas) , which includes about 4 million cells profiled by MERFISH . Section title: Spatial motifs can serve as structural signatures for tissue classification Educational score: 4.112175464630127 Domain: biomedical Document type: Study Language: en Thus far, we have focused on spatial maps of cell types in neural tissues obtained through imaging-based methods. The complexity of neural tissues, with numerous intermingled cell types, and the single-cell resolution of imaging-based techniques make these datasets particularly well-suited for spatial motif analysis. However, SMORE is a general framework, agnostic of the methodology used for spatial profiling. Here, we demonstrate the broader utility of our method by analyzing transcriptomic maps of mouse embryos at embryonic day (E) 8.5 and 9, generated using Slide-seq . Section title: Spatial motifs can serve as structural signatures for tissue classification Educational score: 4.203429222106934 Domain: biomedical Document type: Study Language: en Our analysis includes data from two E8.5 embryos, with 15 and 17 sagittal sections collected at 30 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\upmu$$\end{document} μ m intervals, and one E9 embryo with 26 sagittal sections collected at 20 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\upmu$$\end{document} μ m intervals. In total, the dataset encompasses 256,487 cells with gene expression profiles spanning 27,554 genes. Following the original study, we used 29 cell states as labels, each assigned by computationally mapping beads to a pre-existing single-cell reference. This approach effectively mapped cell states to their expected spatial domains, as shown for 10 selected cell states Fig. 9 a. Fig. 9 Spatial motif analysis of a slide-seq mouse embryo dataset. a Cell type distributions in two E8.5 embryos (replicates) and one E9.0 mouse embryo. Three example sagittal sections from each embryo are shown. b First 10 output motifs obtained using global shuffling to generate the control data are highlighted on the tissue graph. Obtained motifs are represented by logos in the bottom. Annotations for the cell types involved in the motifs are either listed in the legend for panel ( a ) or at the bottom of panel b . Each motif is indicated by a different color in the highlighted tissue graph, with the colors noted on top of the motif logos. c Clustergram obtained based on correlation of the frequency of first 30 motifs in different embryo tissues Section title: Spatial motifs can serve as structural signatures for tissue classification Educational score: 4.089633464813232 Domain: biomedical Document type: Study Language: en As expected, due to the coarse-grained classification of cell states, most of the top motifs were composed of repeating patterns of a single cell state . These homotypic motifs represent regions of the sample that are broadly labeled, for example as brain or heart. Among the top 10 motifs, some also represent the boundary of two tissues, for example presomitic mesoderm and neuromesodermal progenitors . Although these motifs lack the complexity seen in neural tissues, they still reveal statistically significant patterns. Therefore, we asked if motif frequency could be used to cluster structurally similar samples. Indeed, clustering based on the frequency of the top 30 motifs successfully grouped the two E8.5 samples together, separating them from the E9 embryo . Section title: Spatial motifs can serve as structural signatures for tissue classification Educational score: 4.32762336730957 Domain: biomedical Document type: Study Language: en An advantage of sequencing-based spatial transcriptomics methods, like Slide-seq, is their ability to capture a comprehensive, unbiased view of gene expression across the tissue. We performed differential gene expression analysis, comparing cells within motifs with the cells of the same type elsewhere in the samples, and found numerous highly significant cases . A notable example is the lower expression of retinoic acid pathway members Crabp1 and Crabp2 in brain cells positioned within a sequence of anterior neuroectoderm cells . This observation aligns with previously reported anterior-posterior expression domains of these genes and may suggest region-specific modulation of RA signaling. Overall, among the 181 unique significant genes (log(p) \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$< -80$$\end{document} < - 80 and absolute delta median \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$> 0.5$$\end{document} > 0.5 ), 40 overlapped with the 352 top enriched genes along the anteroposterior and dorsoventral axes reported in the original study . This overlap, observed from a pool of 27,554 genes, is statistically significant ( p -value \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$= 8.99e-38$$\end{document} = 8.99 e - 38 ). Section title: Spatial motifs can serve as structural signatures for tissue classification Educational score: 4.223845958709717 Domain: biomedical Document type: Study Language: en Together, this analysis demonstrates SMORE’s versatility in identifying spatial motifs across diverse tissue types and transcriptomics platforms. It also highlights the scalability of our motif-specific gene expression analysis for genome-wide, sequencing-based data and showcases clustering of tissues based on frequency of their spatial motifs. Fig. 10 Motif specific gene expression analysis of mouse embryonic samples. a Selected cases and genes with at least one absolute log p -value greater than 100 and absolute delta median greater than 1. The gene names and their motif address (motif number - position in motif - cell type - embryo number; MPCE) are included on the x - and y -axis, respectively. Embryos are numbered as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$1\text {:E8.5\_rep1,} 2:\text {E8.5\_rep2, and} 3:\text {E9}$$\end{document} 1 :E8.5\_rep1, 2 : E8.5\_rep2, and 3 : E9 . b Motif logos for the motifs that are not included in Fig. 9 but are present in the panel ( a ) heatmap. Cell type annotations are shown at the bottom. c Expression level of Crabp1 in all “brain” cells (cell state A) in the E9.0 embryo viewed from the top along the z -axis (left) compared to brain cells in motif #25 (right). d same as c for Crabp2 expression level. Both Crabp1 and Crabp2 are identified as significantly downregulated in brain cells within motif #25 compared to other brain cells, as highlighted in the panel ( a ) heatmap Section title: Discussion Educational score: 3.6390249729156494 Domain: biomedical Document type: Other Language: en Spatial transcriptomics is a rapidly growing field. We have seen significant innovation in the field over the past few years, resulting in a multitude of techniques and consistent improvements in their efficiency and scalability. Concurrently, application of spatial transcriptomics has expanded beyond specialized groups to the broader community of biomedical researchers. There are already several commercial platforms available to researchers, and it is expected that additional options will become available in the near future. Therefore, the need for innovative computational methods to extract biologically relevant information from this type of data is on the rise. Section title: Discussion Educational score: 4.100210189819336 Domain: biomedical Document type: Study Language: en In this work, we introduce a method for identifying patterns of cell type arrangements with arbitrary length. There are two major contributions that make this task possible: a method for unbiased sampling of paths from a graph (URPEN) and a method for identifying motifs in such samples (SMORE). Our approach is general and can be applied to any system with sufficient complexity profiled with any spatial omics method. This includes solid tumors and organoids, where greater heterogeneity increases the need for statistical analysis. It is also not limited to two-dimensional maps and can be readily adapted for three-dimensional data. In addition to the application presented here, individual components of our method can be independently employed in a range of other contexts that are modeled as a graph. For example, path sampling via random walk has been used in applications ranging from network representation learning to estimation of similarity measures . Unbiased path sampling using URPEN can offer benefits over random walk in such applications. Detailed evaluation of performance improvement with URPEN needs further investigation. Section title: Discussion Educational score: 4.05906343460083 Domain: biomedical Document type: Study Language: en Spatial motifs can be explained in terms of their functional significance or developmental mechanisms that generate a specific cell type arrangement. Therefore, they can be used to generate hypotheses and further our understanding of tissue biology. We have provided a few examples in this study. This includes association of RBCs with type 2 and 6 cone bipolar cells that can be involved in the primary scotopic pathway and downregulation of Grm6 in type 5 b ON bipolar cells near type 1b cells that offers a possible mechanism for the function of these atypical bipolar cells. Interpretation of each spatial motif at this point can only be done on a case-by-case basis, in the context of what is known about the cell types involved. This can begin with length 2 motifs, which are easier to interpret, and progress to higher lengths in a stepwise manner. For motifs that consist of more than one seed, each seed can also be investigated separately. Section title: Discussion Educational score: 4.11094856262207 Domain: biomedical Document type: Study Language: en Our findings also underscore the potential of spatial motifs as powerful tools for systematically characterizing tissues based on their cellular architecture. It will be interesting to explore more systematic ways of utilizing spatial motifs for characterizing tissues. For example, the set of all spatial motifs in a sample can provide a quantitative representation of the tissue structure. These representations can be valuable in classifying tissues with subtle differences in their cellular architecture, such as various cancer subtypes. In this study, we showcase an example of such classification for mouse embryonic tissues from E8.5 and E9 stages. To enhance this utility, further analysis is required to optimize key factors, including the normalization of high- and low-frequency motifs, selection between motifs, incorporation of features beyond motif frequency, and identification of the optimal motif length for best performance. Section title: Discussion Educational score: 4.200767517089844 Domain: biomedical Document type: Study Language: en Our analysis here is constrained by certain technical limitations of the existing data. In datasets we analyzed, each cell is represented by a point in the tissue, which is typically the center of its nucleus. This ignores variation in size of the cells and their receptive fields. Position of the cell body may also not be a good indicator of neuronal connectivity. Furthermore, our motifs are currently confined to short range local neighborhoods surrounding each cell. Expanding the method to incorporate longer range interactions could be an interesting next step, either by clustering identified motifs or by permitting gaps in the motif sequence. Gene expression analysis can be informative as shown here. However, gene panels in imaging based spatial transcriptomics datasets are often selective, focusing on known cell type markers. In contrast, sequencing-based spatial methods offer expansive genomic coverage, but their measurements can be more noisy and sparse. As more, scalable and multimodal spatial methods become available, SMORE has the potential to discover more intricate relationships between the spatial positioning of cells and their functional characteristics, including gene expression. Section title: Conclusions Educational score: 4.303569793701172 Domain: biomedical Document type: Study Language: en In conclusion, SMORE provides a novel and robust method for identifying spatial motifs in complex tissue structures. By capturing the sequential order of cells, SMORE fills a critical gap and complements the rapidly growing suite of spatial analysis methods. We present substantial algorithmic developments that enable efficient, unbiased sampling of paths from neighborhood graphs and discovery of motifs in the resulting cell type sequences. By rigorously investigating the performance of each component of our method, we quantitatively demonstrate their accuracy, specificity, and sensitivity. The application of SMORE to spatial maps of the mouse retina, brain, and embryonic tissue illustrates its utility in uncovering previously unrecognized patterns of cell type organization and contextualizing their biological significance through gene expression analysis. We further demonstrate the versatility and scalability of our method by analyzing samples spanning a wide range of cell and cell type counts, profiled using different spatial transcriptomics platforms. Together, our results highlight the capability of SMORE to illuminate the substantial complexity of neural tissues, provide novel insight even in well studied models, and generate experimentally testable hypotheses. Section title: Methods Educational score: 4.030875205993652 Domain: biomedical Document type: Study Language: en In order to apply the SMORE method on the spatial structure of the cell types, spatial transcriptomics dataset is imported and the neighborhood graph based on cell positions is created. Control data is generated using one of two methods: global shuffling and kernel shuffling. As an example, Additional file 1 : Fig. S1 illustrates a kernel for the center node (highlighted in magenta). In this figure, K is set to 4 and 6, indicating that all nodes within K neighborhoods of the center node are part of the kernel. Section title: Methods Educational score: 3.3034274578094482 Domain: biomedical Document type: Study Language: en nTrain instances of shuffled labels are generated. Labels for fixed nodes are not shuffled and labels for the other nodes are not shuffled with the fixed nodes. The graph is sampled with URPEN with the specified sampling frequency and the labels for the sampled paths are imported from either the original cell type labels or the set of nTrain shuffled labels created for the control data. After incorporating the reverse paths into the dataset, both primary and control data are fed into the SMORE method to identify motifs. The algorithms for path sampling and motif discovery are described in detail below. Section title: Uniform path sampling Educational score: 4.016736030578613 Domain: biomedical Document type: Study Language: en The topological relations inside the spatial data can be represented as graphs. A graph is defined as an ordered pair G = ( V ; E ) consisting of a nonempty set of vertices V and a set of edges E of two-element subsets of V . In the following, we are dealing with undirected graphs, but the path sampling algorithm can equally be applied to directed graphs as well. Vertices in V are assumed to be uniquely indexed by the integers \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$1, \ldots , n$$\end{document} 1 , … , n , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$n=|V|$$\end{document} n = | V | is defined as the size of the graph. \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$v> u$$\end{document} v > u is used to indicate that the index of a vertex v is larger than that of a vertex u . For a vertex \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$v \in V_0$$\end{document} v ∈ V 0 , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V_0$$\end{document} V 0 is a subset of vertices, its forward neighborhood with respect to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V_0, N_{frw}(v, V_0)$$\end{document} V 0 , N frw ( v , V 0 ) , is defined as the set of all vertices from \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V\setminus V_0$$\end{document} V \ V 0 which are adjacent to v . The neighborhood of a vertex is simply its forward neighborhood with respect to the empty set, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\emptyset$$\end{document} ∅ . Section title: Uniform path sampling Educational score: 3.6487226486206055 Domain: biomedical Document type: Study Language: en The developed algorithm for finding motifs in graphs consists of two main components; first a method to uniformly sample the graph, and second, a procedure to find motifs inside obtained sequences. The sampling algorithm takes a graph G and all paths inside the graph are sampled uniformly. In a network, a path is a walk that does not intersect itself. Selected paths are also constrained to be radial. Radial condition in a spatially embedded network is defined as the requirement that actual physical distance along a path monotonically increases along the sequence of edges in the path. The graph on spatial dataset is created based on the distance between nodes, therefore, the radial requirement enables us to better interpret output motifs in our experiment on the real dataset. Section title: Uniform path sampling Educational score: 2.5548651218414307 Domain: other Document type: Other Language: en The Path Enumeration algorithm (PEN) (Algorithm 1) enumerates all paths of length k within the graph. The algorithm begins with a vertex v from the input graph and adds only those vertices to the set that are neighboring the newly added vertex w but are not already in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V_{path}$$\end{document} V path . To prevent enumeration of both the path and its reverse, the index of the last vertex in the enumerated path must be greater than that of v , though this requirement is not necessary for directed graphs. The proof for the correctness of PEN is similar to that of the ESU algorithm . Section title: Uniform path sampling Educational score: 2.360002040863037 Domain: other Document type: Other Language: en We can modify the PEN algorithm to enumerate a subset of paths such that each path is reached with equal probability. This is implemented by calling the ExtendPath function at lines 3, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E_6$$\end{document} E 6 of the PEN algorithm with probability \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p_d$$\end{document} p d . This new algorithm is called Uniform Random Path Enumeration, URPEN. The method is tested in the “ URPEN enables efficient and unbiased sampling of neighborhood graphs ” section on a random graph to validate its accuracy numerically. Section title: Compute significance Educational score: 4.212855815887451 Domain: biomedical Document type: Study Language: en The significance of each initial seed is obtained by the negative binomial test. The Poisson distribution arises naturally in the study of data taking the form of counts. If a data point y follows the Poisson distribution with rate \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\theta$$\end{document} θ , then the probability distribution of a single observation y is \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y\sim \text {Poisson}(\theta )$$\end{document} y ∼ Poisson ( θ ) . The Poisson model for data points \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathbf {y_v}=[y_1, y_2, \ldots , y_n ]$$\end{document} y v = [ y 1 , y 2 , … , y n ] can be extended to the form \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y_i\sim \text {Poisson}(w_i\theta )$$\end{document} y i ∼ Poisson ( w i θ ) , where the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$w_i$$\end{document} w i values are known positive explanatory values proportional to the population, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\theta$$\end{document} θ is the unknown parameter of interest. Seed number in each graph can be modeled as a Poisson distribution where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y_i$$\end{document} y i is the number of paths of some specific type (seed) in the graph, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\theta$$\end{document} θ is the underlying rate in units of seeds per graph. Section title: Compute significance Educational score: 4.1727094650268555 Domain: biomedical Document type: Study Language: en To perform Bayesian inference, we need a prior distribution for the unknown rate. We use a gamma distribution as prior, which is conjugate to the Poisson. With prior distribution \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\text {Gamma} (\alpha , \beta )$$\end{document} Gamma ( α , β ) , the resulting posterior distribution is obtained as 1 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} \theta | \mathbf {y_v}\sim \text {Gamma} \left(\alpha + \sum\limits_{i=1}^n y_i, \beta + \sum\limits_{i=1}^n w_i \right) \end{aligned}$$\end{document} θ | y v ∼ Gamma α + ∑ i = 1 n y i , β + ∑ i = 1 n w i Section title: Compute significance Educational score: 4.255065441131592 Domain: biomedical Document type: Study Language: en The known form of the prior and posterior densities can be used to find the marginal distribution for a single observation, which has a predictive distribution as 2 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} p(y_0|\mathbf {y_v})=\frac{p(y_0|\theta ) p(\theta |\mathbf {y_v})}{p(\theta |y_0, \mathbf {y_v})}=\text {NegBin}(\alpha _n, p_n), \end{aligned}$$\end{document} p ( y 0 | y v ) = p ( y 0 | θ ) p ( θ | y v ) p ( θ | y 0 , y v ) = NegBin ( α n , p n ) , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha _n=\alpha + \sum _{i=1}^n y_i$$\end{document} α n = α + ∑ i = 1 n y i , and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p_n=\frac{w_0}{(\beta _n +w_0)}$$\end{document} p n = w 0 ( β n + w 0 ) with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta _n =\beta + \sum _{i=1}^n w_i$$\end{document} β n = β + ∑ i = 1 n w i . Assuming that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y_0$$\end{document} y 0 is the seed number in the primary graph, p value for some specific observation is obtained as 3 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} P=\sum _{k=y_0}^\infty {n +k-1 \atopwithdelims ()k} p_n^k(1-p_n)^n, \end{aligned}$$\end{document} P = ∑ k = y 0 ∞ n + k - 1 k p n k ( 1 - p n ) n , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y_0$$\end{document} y 0 , and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y_i$$\end{document} y i , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$i=1, 2, \ldots , n$$\end{document} i = 1 , 2 , … , n are the number of ZNIC sites of the specific seed in primary and control data, respectively. \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$w_i$$\end{document} w i numbers are the total number of ZNIC seeds in the respective graph. In our experiments, prior \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha$$\end{document} α and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta$$\end{document} β values are assumed to be equal to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y_0$$\end{document} y 0 , and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$w_0$$\end{document} w 0 , respectively. The first nEval significant seeds according to this criterion are passed to the next stage of refinement and enrichment. Section title: Refinement and nested seed enrichment Educational score: 4.151231288909912 Domain: biomedical Document type: Study Language: en The refinement and seed enrichment both use the same process of enrichment, except that refinement is only one iteration, and seed enrichment is NREFIter iterations. nEval motifs from initial evaluation step are first enriched for one iteration and top NREF motifs are further refined in seed enrichment block for NREFIter iterations or until p value does not improve. At each iteration, all seeds with positive likelihood ratio scores with respect to the PWM matrix obtained from the previous iteration are sorted with their score and p values obtained in the initial evaluation block and their ZNIC counts are computed. More specifically, it’s computed how many ZNIC samples each seed contributes to the previous samples. These counts are used to obtain significance with the same negative binomial test obtained in 4 . For the negative control data, sum of the counts over nTrain control data are used for significance computation. Section title: Refinement and nested seed enrichment Educational score: 4.15200138092041 Domain: biomedical Document type: Study Language: en The PWM score that minimizes p value (maximizes absolute log p value) is selected to create the PWM matrix for the next iteration. There is an option in the algorithm to use differential enrichment where seeds are added to the PWM until the p value is decreasing. For example, if there are four PWM score thresholds with ZNIC log p values, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$[-10, -11, -9, -13]$$\end{document} [ - 10 , - 11 , - 9 , - 13 ] , the default mode will consider lowest score threshold which is equivalent to log \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p{\text{value}}=-13$$\end{document} p value = - 13 , but differential p value will consider the threshold corresponding to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\log-p\mathrm{value}=-11$$\end{document} log - p value = - 11 . The differential p value option will generally lead to a simpler motif structure. Default mode is used for bipolar and 3D hypothalamus dataset, and differential p value is used for the preoptic area of mouse hypothalamus. Section title: Refinement and nested seed enrichment Educational score: 4.283367156982422 Domain: biomedical Document type: Study Language: en Maximum likelihood estimation is used to estimate a new version of the motif PWM matrix for the next iteration. This step is iterated until the p value is decreasing or the maximum number of NREFIter is performed. In order to perform maximum likelihood estimation, let us assume that we have L distinct cell types in our dataset, encoded as integer numbers from 1 to L . Assuming that the initial seed consists of W letters, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$S = s_1, s_2, \ldots , s_W$$\end{document} S = s 1 , s 2 , … , s W , the PWM matrix, M , is a \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$L \times W$$\end{document} L × W matrix where W is the length of the searched motif. Elements of the PWM matrix in the first iteration are obtained as follows, 4 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} \textbf{M}(i, j)= \left\{ \begin{array}{ll} {1+\rho \textbf{b} (s_j)}/{1+\rho }& \text {if}\ s_{j} = i\\ \rho /{1+\rho } & {\text {otherwise}} \end{array}\right. \end{aligned}$$\end{document} M ( i , j ) = 1 + ρ b ( s j ) / 1 + ρ if s j = i ρ / 1 + ρ otherwise where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho$$\end{document} ρ is the Dirichlet prior set to 0.01 in our experiment, and b is the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$L \times 1$$\end{document} L × 1 vector of background probabilities of the cell types. For the subsequent iterations, the maximum likelihood estimation for M matrix is obtained as follows , 5 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} \hat{\textbf{M}}=\sum _{i=1}^{K} {P_i Z_i/N_i \textbf{I}_i } +\rho \textbf{b} \end{aligned}$$\end{document} M ^ = ∑ i = 1 K P i Z i / N i I i + ρ b Section title: Refinement and nested seed enrichment Educational score: 4.289836883544922 Domain: biomedical Document type: Study Language: en The PWM matrix, M , is obtained by normalizing \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hat{\textbf{M}}$$\end{document} M ^ through the columns. K is the number of seeds involved in the motif, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\textbf{I}_i$$\end{document} I i is the indicator matrix of ith seed, which is equivalent to PWM matrix of 4 with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho$$\end{document} ρ set to 0. Zi , Ni , and Pi are the incremental ZNIC counts, total ZNIC counts, and log p value of the ith seed involved in the motif, respectively. Total ZNIC counts are the number ZNIC sites of the ith seed and incremental ZNIC counts are the fraction of these sites that don’t have any node in common with previous seeds, up to i ’th seed. Section title: Applying SMORE on synthetic and real data Educational score: 2.5211262702941895 Domain: biomedical Document type: Study Language: en We have tested SMORE on synthetic data and real data. The results on synthetic data helps to quantify the algorithm’s performance by assessing its ability to identify known truth patterns at various embedding frequencies. Subsequently, SMORE has been applied to multiple real spatial transcriptomic datasets, each of which is thoroughly detailed in its corresponding section. Section title: Applying SMORE on synthetic and real data Educational score: 4.142740249633789 Domain: biomedical Document type: Study Language: en The background frequency in synthetic data experiment is assumed to be near uniform, with 6 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} {\textbf {b}}_F=[1, 1/2, 1/3, \ldots , 1/12]^{1/4}, \end{aligned}$$\end{document} b F = [ 1 , 1 / 2 , 1 / 3 , … , 1 / 12 ] 1 / 4 , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\textbf{b}_F$$\end{document} b F is the background frequency and it is assumed to be known to the algorithm. Cell type labels, other than the ones for the motifs, are distributed randomly among available nodes according to their frequency. This specific form of background frequency is arbitrary and is designed to have at most twofold difference in the cell type frequency to avoid potential unwanted repeating cell type patterns like AAAA. Section title: Applying SMORE on synthetic and real data Educational score: 4.056141376495361 Domain: biomedical Document type: Study Language: en Output motifs are represented by sequence logos. Some output motifs are simple in structure and some are more complex, consisting of multiple cell types in each position. Simple logos like AAAA indicate a repetitive pattern of A type cells interconnected in the graph within that particular tissue. In more complex motifs like (AB)AAA, the first position can be occupied by either A or B. Embedded length-4 patterns in the synthetic data follow a format like (A/B)CDE, where one variable position can be filled by either cell type A or B, each with equal probability. The remaining positions in the pattern (CDE) are fixed to specific cell types. For a 2% embedding, the nodes corresponding to 60 random path samples from the total length-4 sampled paths are labeled as ACDE and another 60 as BCDE, while all other nodes in the graph are randomly labeled. Section title: Applying SMORE on synthetic and real data Educational score: 4.155911445617676 Domain: biomedical Document type: Study Language: en In Fig. 3 a, the Pearson correlation coefficient (PCC) between the extracted motifs and the embedded motifs is shown. The Tomtom method is employed to identify the best enriched matches among the 10 output motifs from SMORE. Tomtom searches for the best match by considering all possible shifts of the query motif with respect to the target motif (the embedded motif in this case). The matching position weight matrices (PWMs) are aligned using the obtained offsets and overlaps from Tomtom, and the PCC is computed and plotted to evaluate the pipeline’s accuracy. Each embedded motif word corresponds to a \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$12 \times 4$$\end{document} 12 × 4 PWM matrix, employing a Dirichlet prior with a weight of 0.01. The Dirichlet prior is a uniform distribution of the cell types. Section title: Computing TPR and FPR Educational score: 4.155645370483398 Domain: biomedical Document type: Study Language: en \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\textrm{TPR}$$\end{document} TPR is computed as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\textrm{TPR}=\textrm{TP}/(\textrm{TP}+\textrm{FN})$$\end{document} TPR = TP / ( TP + FN ) , where TP (true positive) denotes the number of output motifs with a correlation exceeding the threshold (0.95 in our context) and a p value below the specified threshold. FN (false negative) is the number of instances with a correlation surpassing the threshold but a p value greater than the specified threshold. Thus, TP + FN represents the overall number of cases with a correlation exceeding the threshold. Section title: Computing TPR and FPR Educational score: 4.005407810211182 Domain: biomedical Document type: Study Language: en FPR is defined as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\textrm{FPR}=\textrm{FP}/(\textrm{FP}+\textrm{TN})$$\end{document} FPR = FP / ( FP + TN ) , with FP (false positive) indicating the number of output motifs possessing a correlation below the threshold and a p value below the specified threshold. TN (true negative) is the number of output motifs with a correlation below the threshold and a p value exceeding the specified threshold. Consequently, FP + TN denotes the total number of cases with a correlation below the threshold. Section title: Gene expression analysis Educational score: 4.308821678161621 Domain: biomedical Document type: Study Language: en One potential method for deriving a functional interpretation of these motifs involves examining gene expression disparities between the cells participating in the motif and those that are not involved. This analysis is carried out in the “ Cells within spatial motifs exhibit gene expression differences compared to other cells of the same type ” section. Each motif is composed of multiple positions, and each position includes one or more cell types. For example, the motif (AB)CDE comprises cell types A and B in its first position. Among all cells labeled as A ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_A$$\end{document} N A ), only a subset, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_{AM}$$\end{document} N AM , takes part in the initial position of this particular motif. Each cell has a gene expression profile. For each gene, the delta median(dMedian) is calculated by subtracting the median expression of the gene in the subset \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_{AM}$$\end{document} N AM cells involved in the motif from the median expression of that gene across all \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_A$$\end{document} N A cells of the specific type. The significance for this delta median value is then computed against a random selection of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_{AM}$$\end{document} N AM cells from the total \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_A$$\end{document} N A cells of that type. Section title: Gene expression analysis Educational score: 4.1919474601745605 Domain: biomedical Document type: Study Language: en Assume that there are \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_{A}$$\end{document} N A cell types of A, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_{AM}$$\end{document} N AM of these cell types is in motif (AB)CDE, with dMedian expression \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x_0$$\end{document} x 0 . One sided p value (significance) for these cells is \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p(\text {dMedian} \ge x_0$$\end{document} p ( dMedian ≥ x 0 ). The probability that dMedian expression of these \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_{AM}$$\end{document} N AM cells is larger than \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x_0$$\end{document} x 0 is the probability that at least \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_0=\text {floor}(N_{AM}/2+1)$$\end{document} N 0 = floor ( N AM / 2 + 1 ) of these cells have expression greater than \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x_0$$\end{document} x 0 , 7 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} p_0=\frac{\sum _{k=N_0}^{N_{AM}} {N_H \atopwithdelims ()k}{N_L \atopwithdelims ()N_{AM}-k} }{{N_A \atopwithdelims ()N_{AM}}} \end{aligned}$$\end{document} p 0 = ∑ k = N 0 AM N H k N L N AM - k N A N AM Section title: Gene expression analysis Educational score: 4.24855899810791 Domain: biomedical Document type: Study Language: en Where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_L$$\end{document} N L is the number of cells (out of all \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_A$$\end{document} N A cells) that have lower than \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x_0$$\end{document} x 0 delta expression, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N_H$$\end{document} N H is the number of cells that have higher than \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x_0$$\end{document} x 0 delta expression. Section title: Supplementary Information Educational score: 2.4941906929016113 Domain: biomedical Document type: Other Language: en Additional file 1: Supplementary Material for SMORE: spatial motifs reveal patterns in cellular architecture of complex tissues. This file contains recommendations for handling large sample numbers, side-by-side comparison of SMORE with HistoCAT and ImaCytE’s performance on the retinal bipolar dataset, and analysis of a whole mouse brain spatial transcriptomics atlas, as well as Figs. S1 to S7 and Table S1. Additional file 2: Review history. | Review | biomedical | en | 0.999995 |
PMC11697876 | Section title: Introduction Educational score: 4.09689998626709 Domain: biomedical Document type: Study Language: en Non-traumatic subarachnoid hemorrhage (SAH) is a life-threatening emergency caused by bleeding in the subarachnoid space caused mainly by a ruptured aneurysm . Despite recent advances in subarachnoid hemorrhage treatment, overall mortality and severe disability remain high, and this represents a major public health concern since the population affected is younger compared with other kinds of stroke. As shown in the Swiss SOS study, of all patients affected by SAH, 1 in 10 patients survived in a dependent state at 1 year, while 22% of patients died within 1 year . Furthermore, among SAH survivors with good functional outcomes, quality of life is often impaired. Section title: Introduction Educational score: 4.345671653747559 Domain: biomedical Document type: Study Language: en The pathophysiology of brain injury in SAH patients is extremely complex and not fully understood. The main determinants of brain injury are early brain injury (EBI) and delayed cerebral ischemia (DCI) . EBI encompasses several disorders occurring within the first 72 h following the aneurysm rupture. Extravasation of blood into the subarachnoid space causes an increase in intracranial pressure (ICP) and consequent reduction of cerebral blood flow and transient global cerebral ischemia. Moreover, hydrocephalus could represent a life-threatening emergency in the acute phase and could aggravate the injury. Other mechanisms leading to poor outcome are vasospasm and DCI . Even though cerebral vasospasm has been considered the main determinant of DCI, recent data show that pathophysiology is far more complex than once thought; in fact, cortical spreading depression, microthrombosis, and impaired collateral circulation could contribute to DCI and consequent brain tissue infarction . Section title: Introduction Educational score: 3.9754064083099365 Domain: biomedical Document type: Study Language: en Predicting outcomes among critical care patients is difficult: Advances in medicine have reduced short-term mortality from critical illness despite an increasing number of older patients, but this poses many questions about the cost of survival. As widely reported, patients surviving critical illness develop long-lasting impairments affecting physical, cognitive, and/or mental health status . Furthermore, among neurocritical care patients, the burden of injury can be significant on long-term outcomes, and this should be considered since the dichotomy survived/death cannot fully describe the impact of the disease on patients. Long-term outcome in SAH is mainly inferred from randomized control trial cohorts, and even fewer data are available from patients with poor grade SAH admitted to intensive care unit (ICU). A recent French study showed as only two-thirds of patients survive at one year, and only one-third of them has a good outcome . Section title: Introduction Educational score: 4.099992752075195 Domain: biomedical Document type: Study Language: en As highlighted by several organizations, including WHO, disability is just a partial description of the health status of a patient ; the patients’ experiences of disability, her/his adaptation, resilience, and the family background contribute defining patient’s quality of life . Glasgow Outcome Score (GOS), its extended form (GOSE) and modified Rankin Scale (mRS) are the most used tools to evaluate disability after SAH, while Short Form (36) Health Survey and EuroQoL are the most used to evaluate the quality of life in this group of patients . The long-term outcomes of SAH patients have been evaluated in several studies . However, to our knowledge, there are no studies that evaluate the relationship between clinical presentation and long-term disability and quality of life in SAH patients admitted to the ICU, a restricted group of patients who often exhibit distinctive outcomes compared to others. Our pilot study aims to describe the long-term outcome and quality of life of patients affected by SAH admitted to our ICU and to establish if there is a relationship between outcome and initial clinical presentation or DCI. Section title: Methods Educational score: 2.7088005542755127 Domain: biomedical Document type: Study Language: en This is a single-center, observational, retrospective cohort study. We retrospectively analyzed our electronic clinical records. The study was approved by the Research Ethics Committee of AUSL Romagna . Informed consent was obtained from all the patients. This study adheres to the applicable STROBE guidelines . Section title: Study population Educational score: 2.2131452560424805 Domain: biomedical Document type: Study Language: en We enrolled all the patients admitted to our ICU from 1st January 2020 to 31st December 2020 with a diagnosis on SAH according to European Guidelines . Section title: Study population Educational score: 2.929222345352173 Domain: biomedical Document type: Study Language: en The inclusion criteria were as follows: Diagnosis of SAH (ICD-9-CM Diagnosis Code 430, nontraumatic SAH, unspecified) at admission in the ICU within the period of the study Age ≥ 18 years-old at follow-up Section title: Study population Educational score: 2.617192268371582 Domain: biomedical Document type: Study Language: en Patients in whom neither neurosurgical nor neurointensive treatments had been started because of catastrophic clinical/radiological signs of brain injury were excluded from data analysis. Section title: Study population Educational score: 1.9670146703720093 Domain: biomedical Document type: Study Language: en Patients who were lost to follow-up were not included in the main analysis. Patients that were not directly admitted to ICU after aneurysm exclusion procedure were not included. Section title: Data collection Educational score: 3.9844064712524414 Domain: biomedical Document type: Study Language: en The following data were extracted from clinical records: Baseline data: age, sex, history of smoking, chronic arterial hypertension, diabetes mellitus, WFNS scale, HH scale, mFS, GCS at admission Aneurysm treatment: endovascular vs neurosurgical, requiring of an external ventricular drain (EVD) Complication occurred during ICU stay: early (< 24 h) intracranial hypertension, hydrocephalus, late (> 24 h) intracranial hypertension, seizures, central neurological fever, hyponatremia, nimodipine interruption due to hypotension, increased middle cerebral artery (MCA) mean flow velocity, vasospasm location, impaired CT perfusion, induced hypertension therapy, endovascular vasospasm treatment Outcome measures: hospital length of stay, 12-month Glasgow Outcome Scale Extended (GOSE), 12-month EuroQoL-5D-3L Index (EQ-5D Index), and EQ-VAS Section title: General management Educational score: 3.4981555938720703 Domain: clinical Document type: Study Language: en Aneurysm exclusion was performed as soon as possible. The type of securing procedure was decided after a multidisciplinary discussion between neuroradiologists, neurosurgeons, and intensivists. EVD was placed in case of acute hydrocephalus, HICP, or for surgical needs. All patients with GCS ≤ 8, delayed awakening after procedure or critical medical condition were admitted to ICU. In all patients, a CT scan was obtained within 24 h after aneurysm exclusion. Section title: Management of vasospasm and delayed cerebral ischemia Educational score: 3.9398739337921143 Domain: clinical Document type: Other Language: en Nimodipine was administered orally 60 mg q4h. If patients showed poor tolerance to nimodipine developing hypotension, nimodipine administration was suspended. Sedation was suspended as soon as possible in all the patients without HICP, delirium, hemodynamic instability, or acute respiratory failure, while TCD monitoring through the acoustic transtemporal window was performed daily to detect ultrasonographic vasospasm . In case of clinical deterioration or ultrasonographic vasospasm, supported by clinical judgment, a CT angiography/CT perfusion or cerebral arteriography was obtained. Patients with vasospasm/DCI were treated with blood pressure augmentation. In case of refractory vasospasm/DCI, endovascular rescue therapy was considered. Section title: Management of vasospasm and delayed cerebral ischemia Educational score: 4.088715553283691 Domain: biomedical Document type: Study Language: en Complications were defined as follows: High intracranial pressure (HICP): This was defined as intracranial pressure > 20 mmHg sustained for a period > 5 min . If it occurred within 24 h from admission, it was defined early HICP; if it occurred after this period, it was defined as late HICP. Seizures: EEG were performed as early as possible in comatose patients. Electrographic and electroclinical seizures, electrographic status epilepticus, and electroclinical status epilepticus were diagnosed according to the current American Clinical Neurophysiology Society guidelines . Seizures were treated with antiepileptic drugs and, in most severe cases, with deep sedation. EEG during sedation holiday was performed to evaluate efficacy of antiepileptic therapy. Central neurological fever: central neurologic fever was defined on clinical judgment accordingly to the criteria reported by Hoker et al. . Hyponatremia: patients requiring sodium implementation to maintain serum level within normal range. Symptomatic vasospasm and delayed cerebral ischemia: accordingly with Rass et al., we used the following definition : ◦ Clinical deterioration: New focal neurological deficit OR GCS 2 points OR NIHSS 2 points once excluded other causes (e.g., fever, hyponatremia, hydrocephalus). ◦ Angiographic vasospasm was defined as a reduction in arteries diameter of at least one-third, measured on either CTA or digital subtraction angiography (DSA). ◦ Delayed cerebral infarction (DCIn) was defined as an infarction on CT scan or MRI scans performed within 6 weeks after SAH, absent from the scan performed between 24 and 48 h after aneurysm occlusion, and not attributable to another cause: aneurysm-securing procedure or EVD placement. Section title: Outcome and telephone interview Educational score: 2.290520429611206 Domain: biomedical Document type: Study Language: en Hospital length of stay (H-LOS) was obtained from electronic health-data records. Days of H-LOS were considered from admission to one of these possible outcomes: death, discharge home, and discharge to rehabilitation institutes. Section title: Outcome and telephone interview Educational score: 4.05490255355835 Domain: biomedical Document type: Study Language: en Telephone interviews were performed between 12 and 15 months after initial bleeding by two operators to evaluate outcome. When patients were unable to reply to the survey, the patient’s caregiver was interviewed. Degree of disability and survival were measured using the GOSE . Favorable outcome was defined as GOSE ≥ 4 while patients with GOSE ≤ 3 as unfavorable outcome . Quality of life was evaluated using EQ-5D-3L . The EQ-5D Index scores were calculated from the vectors by using the UK tariff . The nominal range of the EQ-5D Index scores is 0 to 1, but negative scores as low as − 0.59 are possible for health states deemed to be worse than death. The EQ-VAS, instead, records the patient’s self-rated health on a 0–100 scale where 0 represents “the worst health you can imagine,” while 100 is the “best health you can imagine.” When the patients are unable to answer, it is asked to caregivers to give the answer the patient would have given. Section title: Endpoints Educational score: 3.2591700553894043 Domain: biomedical Document type: Study Language: en Objectives our study were as follows: To describe the long-term outcome of patients admitted to ICU following SAH To describe quality of life of patients admitted to ICU following SAH Section title: Endpoints Educational score: 2.6499385833740234 Domain: biomedical Document type: Study Language: en The secondary objective of the study was to establish if there is a correlation between baseline characteristics, clinical course and outcome. Section title: Statistical analysis Educational score: 2.1904921531677246 Domain: biomedical Document type: Study Language: en Statistical analysis was performed using the software IBM SPSS 22.0. Data are reported as mean and standard deviation (SD), median and interquartile range (IQR), and number and percentage (N, %), depending on the underlying distribution. Section title: Statistical analysis Educational score: 3.2803571224212646 Domain: biomedical Document type: Study Language: en Independent Student’s t test, Mann–Whitney U test, Pearson’s chi-squared test, Fisher’s exact test, and Kruskal–Wallis test were used to test any difference between the “favorable” and “unfavorable “groups. Section title: Statistical analysis Educational score: 3.1520793437957764 Domain: biomedical Document type: Study Language: en Secondly, to test correlations between different variables, we measured Spearman’s rank correlation coefficient. Section title: Statistical analysis Educational score: 2.094917058944702 Domain: biomedical Document type: Study Language: en Due to small sample size, we did not use binary logistic regression analysis as it not reliable in this situation. A p value less than 0.5 is statistically significant. Section title: Baseline data Educational score: 2.0854218006134033 Domain: biomedical Document type: Study Language: en Thirty-eight patients were eligible for statistical analysis . Fig. 1 Flowchart for cohort selection Section title: Baseline data Educational score: 4.136201858520508 Domain: biomedical Document type: Study Language: en Table 1 summarizes main baseline characteristics. Table 1 Relation between baseline characteristics at admission and outcome Total Favorable* Unfavorable* p V alue Missing Female N (%) 24 (63.2) 18 (75.0) 6 (25.0) 0.081 - Male N (%) 14 (36.8) 6 (42.9) 8 (57.1) Current smoking N (%) 11 (28.9) 6 (54.5) 5 (45.5) 0.493 Chronic hypertension N (%) 21 (55.3) 13 (61.9) 8 (38.1) 0.859 - Type II diabetes N (%) 2 (5.3) 2 (100) - 0.267 - Age Median (IQR) 58 (20) 53.5 (17) 60 (19) 0.098 - Glasgow Come Scale N (%) 37 23 (62.1) 14 (37.8) 0.156 1 Median (IQR) 11 (8.25) 13 (5.5) 6 (11) WFNS scale 1 N (%) 10 (27.0) 6 (60) 4 (40) 0.078 1 2 N (%) 5 (13.5) 5 (100) - 3 N (%) 7 (18.9) 5 (71.4) 2 (28.6) 4 N (%) 5 (13.5) 4 (80) 1 (20) 5 N (%) 10 (27.0) 3 (30) 7 (70) Hunt-Hess scale 1 N (%) - - - 0.033 1 2 N (%) 11 (29.7) 7 (63.6) 4 (26.4) 3 N (%) 9 (24.3) 9 (100) - 4 N (%) 3 (8.1) 1 (33.3) 2 (66.7) 5 N (%) 14 (37.8) 6 (42.9) 14 (37.8) mFisher scale 1 N (%) - - - 0.165 - 2 N (%) 6 (15.9) 5 (83.3) 1 (16.7) 3 N (%) 3 (7.9) 3 (100) - 4 N (%) 29 (76.3) 16 (55.2) 13 (44.8) *Percentages in the columns “favorable” and “unfavorable” refer to the variable analyzed, not to the overall population Section title: Baseline data Educational score: 2.0301930904388428 Domain: biomedical Document type: Study Language: en Twenty-four (63.2%) patients were female. Median age was 56 years old (IQR 20). The median GCS on arrival was 11 (IQR 8.25). Section title: Baseline data Educational score: 1.6909048557281494 Domain: biomedical Document type: Study Language: en There were no age and sex differences between favorable/unfavorable outcome groups. Comorbidities evaluated in our study did not show any difference among the two groups. Section title: Baseline data Educational score: 2.4508297443389893 Domain: biomedical Document type: Study Language: en One patient had no GCS reported on the record. This patient was included in the primary outcome analysis, but it was excluded in the secondary outcome analysis requiring that data. GCS at admission was lower in the unfavorable outcome group, but it did not show a linear relation with GOSE. Section title: Baseline data Educational score: 1.9915754795074463 Domain: biomedical Document type: Study Language: en WFNS scale, HH scale and mFS are summarized in Table 1 . Section title: Baseline data Educational score: 2.2397806644439697 Domain: biomedical Document type: Study Language: en In our cohort of patients, only HH scale showed a significant relation with disability at 1 year. Section title: Univariate analysis showed no difference between surgical vs endovascular treatment in our population Educational score: 1.6545087099075317 Domain: biomedical Document type: Other Language: en One patient did not receive any treatment because it was not detected any lesion (SAH sine materia ). Section title: Univariate analysis showed no difference between surgical vs endovascular treatment in our population Educational score: 2.5054094791412354 Domain: biomedical Document type: Study Language: en Twenty-two (57.9%) patients had hydrocephalus at admission. EVD was placed in 23 patients (60.5%). In one patient, EVD was placed not to treat hydrocephalus but for surgical purposes. Section title: Complications Educational score: 4.23178768157959 Domain: biomedical Document type: Study Language: en Table 2 summarizes relation between clinical course in ICU and outcome. Table 2 Relation between clinical course in ICU and outcome Total Favorable* Unfavorable* p Value Missing Treatment Endovascular N (%) 19 (51.3) 11 (57.9) 8 (42.1) 0.582 1 Surgical N (%) 18 (48.6) 12 (66.7) 6 (33.3) Hydrocephalus N (%) 22 (57.9) 13 (59.1) 9 (40.9) 0.542 - Neurological fever N (%) 27 (71.0) 18 (66.7) 9 (33.3) 0.482 Early HICP (<24 h admission) N (%) 11 (28.9) 4 (36.4) 7 (63.6) 0.028 - Late HICP (>24 h admission) N (%) 10 (26.3) 4 (40) 6 (60) 0.077 - Hyponatremia N(%) 18 (47.4) 12 (66.7) 6 (33.3) 0.671 Seizures N (%) 5 (13.6) 3 (60.0) 2 (40.0) 0.569 - Nimodipine interruption N (%) 12 (31.6) 9 (75.0) 3 (25.0) 0.309 - Clinical deterioration N (%) 7 (18.4) 5 (71.4) 2 (28.6) 0.693 - TCD Vmean MCA > 120 cm/sec N (%) 16 (42.1) 10 (62.5) 6 (37.5) 0.942 - TCD Vmean MCA > 160 cm/sec N (%) 12 (31.6) 8 (66.7) 4 (33.3) 0.760 - TCD Vmean MCA > 200 cm/sec N (%) 8 (21.0) 6 (75.0) 2 (25.0) 0.434 - Vasospasm (MRA/CTA or catheter angiography) N (%) 13 (34.2) 9 (69.2) 4 (30.8) 0.931 Impaired CT/MR perfusion N (%) 4 (10.5) 2 (50) 2 (50) 0.409 Hospital length of stay (H-LOS) Median (IQR) 22 (12) 19.5 (13) 22.5 (8) 0.540 *Percentages in the columns “favorable” and “unfavorable” refer to the variable analyzed, not to the overall population Section title: Complications Educational score: 2.907973527908325 Domain: biomedical Document type: Study Language: en Among complications occurred during ICU-stay only early HICP was related with unfavorable outcome ( p = 0.028). Section title: Complications Educational score: 3.3321778774261475 Domain: biomedical Document type: Study Language: en Eleven (28.9%) patients developed early HICP, while 10 (26.3%) developed late HICP. Intracranial hypertension was treated implementing sedation, with hyperosmolar therapy, CSF withdrawal, normo-hypocapnia, and, in most extreme cases, surgical decompression. Section title: Vasospasm and DCI Educational score: 3.937868118286133 Domain: biomedical Document type: Study Language: en Figure 2 summarizes incidence of vasospasm and DCI. Seven patients (18.4%) showed clinical deterioration defined as new focal neurological deficit or loss of 2 points on GCS or 2 points on NIHSS. All of them had an increase in MCA mean flow velocities of at least 120 cm/sec. Fig. 2 Vasospasm and delayed cerebral ischemia detection Section title: Vasospasm and DCI Educational score: 3.9846785068511963 Domain: biomedical Document type: Study Language: en Of the 16 patients with MCA mean flow velocities > 120 cm/s, CT angiography and/or arteriography were performed in fifteen patients (39.5%). Vasospasm was confirmed on CTA/arteriography in thirteen patients (34.2%). Twelve patients (31.6%) required induced therapeutic hypertension. Nimodipine was interrupted in twelve patients (31.6%) due to poor tolerance. Section title: Vasospasm and DCI Educational score: 3.3873989582061768 Domain: biomedical Document type: Study Language: en Only four patients (10.5%) showed impaired perfusion on CT scan. Of the four patients with impaired CT perfusion, three patients underwent endovascular rescue treatment. Only one patient, the one with impaired CT perfusion who did not undergo to endovascular rescue therapy, developed delayed cerebral infarction (DCIn). Section title: Outcome Educational score: 2.7375402450561523 Domain: biomedical Document type: Study Language: en Median H-LOS was 22 days (IQR 12), and we did not find any significantly differences among the two groups [19.5 (IQR 13) vs 22.5 (IQR 8), p = 0.540]. Section title: Outcome Educational score: 3.889460563659668 Domain: biomedical Document type: Study Language: en Long-term neurological outcome of the 38 patients is displayed on Table 3 . Twenty-four patients (63.2%) had favorable outcome (GOSE ≥ 4). GOSE at 1 year is summarized on Table 3 . Table 3 GOSE at one year GOSE at 1 year N (%) Unfavorable outcome 1 9 (23.7) 2 1 (2.6) 3 4 (10.5) Favorable outcome 4 5 (13.2) 5 1 (2.6) 6 5 (13.3) 7 8 (21.0) 8 5 (13.2) Section title: Outcome Educational score: 2.0801422595977783 Domain: biomedical Document type: Study Language: en Quality of life was evaluated among patients who were alive at 1 year. Section title: Outcome Educational score: 4.092825889587402 Domain: biomedical Document type: Study Language: en Among 29 patients (76.3%) survived at 1 year, median EQ-5D Index was 0.743 (IQR 0.287), while median EQ-VAS was 74.79 (IQR 18.5). Median EQ-5D Index and median EQ-VAS were higher among patients with favorable outcome [EQ-5D Index 0.796 (IQR 0.2) vs − 0.331 (IQR 1.0) p = 0.037], [EQ-VAS 80 (IQR 20) vs 50 (IQR 37.5) p = 0.003]. Section title: Outcome Educational score: 3.9929721355438232 Domain: biomedical Document type: Study Language: en Relations between GOSE and EQ-5D Index and EQ-VAS are shown in Table 4 and Fig. 3 . Table 4 Relation between GOSE and EQ-Index GOSEEQ-VAS 2 − 0.331 (0) p = 0.051 20 (0) p = 0.019 3 0.144 (1.2) 50 (30) 4 0.587 (0.45) 70 (7.5) 5 0.587 (0) 96 (0) 6 0.812 (0.38) 85 (18.75) 7 0.83 (0.18) 80 (15) 8 0.812 (0.22) 88 (16.25) Data are reported as median and interquartile range (IQR) Fig. 3 Distribution of EQOL-Index ( a ) and EQOL-VAS ( b ) in the group with favorable (blue) and unfavorable (red) outcome Section title: Discussion Educational score: 2.9829230308532715 Domain: biomedical Document type: Study Language: en To our knowledge, this is the first study that describes long-term disability and quality of life of SAH patients admitted to ICU as primary outcome. Section title: Discussion Educational score: 2.1595308780670166 Domain: biomedical Document type: Other Language: en As highlighted by several papers, patient-centered outcomes are key elements in clinical studies . Section title: Discussion Educational score: 2.597437620162964 Domain: biomedical Document type: Study Language: en Regarding disability, the study of Chalard et al. is the only one that evaluates long-term disability in a cohort of SAH patients admitted to ICU. This study showed a higher incidence of poor outcome compared to our cohort . Section title: Discussion Educational score: 2.917692184448242 Domain: biomedical Document type: Study Language: en There are some reasons that could explain these findings: First of all, we used a different scale to evaluate disability compared with the study reported above. We used GOSE rather than mRS because in our center is the most used scale to evaluate long-term outcome in patients with acute brain injury and, with GOS, it has been widely used in literature in SAH patients . Section title: Discussion Educational score: 2.3073601722717285 Domain: biomedical Document type: Study Language: en Secondly, we excluded patients with catastrophic brain injury in which treatment was considered futile since admission. Section title: Discussion Educational score: 4.003036022186279 Domain: biomedical Document type: Study Language: en Finally, our higher incidence of good outcome could be related to a low cut-point on GOSE. There is no consensus on the cut-off point to define favorable outcome with GOSE in acute brain injury patients. As shown in a recent paper by Zuckerman et al. there is a wide range of cut-points on GOSE in patients with acute brain injury that ranges from 3 to 7 . Accordingly with the other authors , we included GOSE 4 among favorable outcome, recognizing functional independence for at least 8 h as a favorable outcome for patients and caregivers. Section title: Discussion Educational score: 2.3754613399505615 Domain: biomedical Document type: Study Language: en Our results seem to support our choice; as shown in Table 3 , EQ-5D Index and EQ-VAS in group GOSE 4 are more similar to higher grades (GOSE 6–8) than to the lower ones. Section title: Discussion Educational score: 4.131861686706543 Domain: biomedical Document type: Study Language: en Another major issue of discussion regarding outcome is the quality of life perceived by the patients. Median EQ-VAS varies significantly among GOSE grades ( p = 0.019), while median EQ-index is not significantly different. This could be related to a small sample-size, but also to a broader effectiveness of EQ-VAS in summarizing overall health that is closer to the patient’s perspective. As reported in Table 3 , the highest GOSE grades are not the ones with the highest values of EQ-5D Index and EQ-VAS. This is a phenomenon known as disability paradox . Several studies have shown that many patients, despite a severe disability after brain injury, enjoy a high quality of life . It is remarkable the broad range of EQ-VAS and EQ-5D Index in the GOSE 3 group in our cohort: In fact, in this group usually considered an unfavorable outcome in studies on acute brain injury, there are a patient with poor quality of life (EQ-5D Index -0.594 and EQ-VAS of 20) and a patient with good quality of life (EQ-5D Index 0.883, EQ-VAS of 80). Should this still be considered a poor outcome, or should we focus our attention on the perceived quality of life? It is a thought question that goes behind the purpose of this study, but that should foster a debate. Section title: Discussion Educational score: 2.8303232192993164 Domain: biomedical Document type: Other Language: en This poses, if possible, even major challenges to physicians when talking about prognostication in patients with poor-grade SAH and highlights the importance of shared-decision making with the patients and/or the family in this field ; moreover, this remarks the importance of patient-centered outcome studies. Section title: Discussion Educational score: 1.6496505737304688 Domain: biomedical Document type: Other Language: en Unfortunately, few are the tools available during ICU stay to evaluate prognosis in this group of patients. Section title: Discussion Educational score: 2.472076892852783 Domain: biomedical Document type: Study Language: en Regarding baseline data, in our cohort, females seem to have a better prognosis compared to males; to our knowledge, in previous reports are reported no sex differences in long-term outcome of SAH patients . This could be related to a small sample size and it will require further studies to understand this finding. Section title: Discussion Educational score: 4.0270094871521 Domain: biomedical Document type: Study Language: en In this study, of the most used severity scale, only HH scale seems to show a relation with poor outcome. This scale, introduced in 1968, was first used to predict the rate of mortality based solely on the clinical features in SAH patients; higher HH grades have been associated with poor outcomes also in more recent studies . However, since HH scale does not take in account the presence of reversible causes of coma such as hydrocephalus and seizures, we agree that this scale should not be used alone to define the prognosis of SAH patients. Section title: Discussion Educational score: 3.9579174518585205 Domain: biomedical Document type: Study Language: en Consistently with other studies , GCS at admission is related to long-term outcome in our cohort. The level of consciousness in patients admitted with SAH could represent the epiphenomenon of the early brain injury that is developing after aneurismal rupture; the pathophysiology of this process is not completely understood and should be the object of further studies. Nonetheless, a poor GCS at admission could be associated with a good recovery as shown by Hoogmeoed et al. . Section title: Discussion Educational score: 3.977634906768799 Domain: biomedical Document type: Study Language: en Among SAH-related complications, only high early intracranial hypertension was related with poor outcome in our cohort. This finding could have different explanations. Early HICP could be related to a well-known cause such as hydrocephalus, but this was not related to poor outcome in our cohort. Possibly, early HICP could be a surrogate marker of EBI due to loss of autoregulation or cerebral edema . Section title: Discussion Educational score: 4.07583475112915 Domain: biomedical Document type: Study Language: en As highlighted in other papers, our data support the lack of relation between vasospasm detected on TCD and/or CTA and long-term outcome. The incidence of vasospasm is similar to other cohorts of patients and emphasizes the importance of distinguishing between vasospasm, DCI and DCIn . As highlighted by recent papers, DCI has a complex pathology in which vasospasm is just one of the determinants of brain injury. TCD and angiographic spasm seem to pose the patients at higher risk of DCI, but this is not related to long-term outcome [ 39 – 41 ]. Section title: Discussion Educational score: 2.1623990535736084 Domain: biomedical Document type: Other Language: en Instead, DCI can lead to DCIn, a well-known factor related to long-term poor outcome. Section title: Discussion Educational score: 4.057764053344727 Domain: biomedical Document type: Study Language: en DCI can be suspected in patients with clinical deterioration or in patients with impaired CT-perfusion . As remarked by the same authors that proposed the definition of clinical deterioration due to DCI in 2010, diagnosis of DCI can be tricky due to several confounders, especially in ICU patients . The presence of several confounders combined with the small sample size could explain the lack of relation between DCI and long-term outcome in our cohort. Another possible explanation is that DCI is not strictly related to DCIn. In fact, in our cohort, only 25% of patients who had impaired CT-perfusion developed DCIn. This seems to support the hypothesis that DCI detected on CT-perfusion still represents a reversible situation that requires the highest quality of care to prevent DCIn . Section title: Limitations Educational score: 2.2417142391204834 Domain: biomedical Document type: Study Language: en The main limitations of the study are the small sample size and the fact that it is a single center study. A larger number of cases would allow multivariate analysis to identify independent outcomes predictors. Section title: Limitations Educational score: 2.2899930477142334 Domain: biomedical Document type: Other Language: en mRS seems to be a better outcome measure for SAH patients, but GOSE is still widely used. Moreover, in our institution, GOSE is widely used as an outcome scale for patients with acute brain injury, and physicians and nurses are well-trained in its use. Section title: Limitations Educational score: 1.8361563682556152 Domain: biomedical Document type: Study Language: en Regarding dichotomizations, there are several cut-offs reported in the literature that could limit the comparison between studies. Section title: Limitations Educational score: 1.8813453912734985 Domain: biomedical Document type: Study Language: en Another limitation is the use of caregivers as surrogate to evaluate QoL, but this is recommended in all the cases in which the patients it is unable to answer. This study does not include patients admitted in good neurological condition and managed in the neurosurgery ward throughout their hospital stay. Section title: Conclusions Educational score: 4.000290870666504 Domain: biomedical Document type: Study Language: en This study describes long-term disability and quality of life in SAH patients admitted to ICU and their relation with clinical features. High HH grades and early HICP were related with unfavorable outcome. Among patients with unfavorable outcome, quality of life has a broad range of variability, and this result should be taken into account when reporting patient-centered outcomes. | Study | biomedical | en | 0.999998 |
PMC11697907 | Section title: Background Educational score: 3.9449093341827393 Domain: biomedical Document type: Review Language: en ADHD is most commonly treated with stimulant and non-stimulant medications, which have been shown to be clinically effective . Extended-release (ER) stimulants provide the benefits of long-acting symptom control leading to greater treatment satisfaction compared to immediate-release (IR) stimulants . These long-acting medications reduce the need for repeated doses, thereby improving adherence and treatment response [ 3 – 5 ]. They also have a lower risk of misuse compared to short-acting IR stimulants . However, IR stimulants are still used to supplement once-daily medications when symptoms are not sufficiently controlled . Prescribers may advise using IR formulations to prolong and boost the therapeutic effects of an ER medication or to curb unwanted effects if the ER dose wears off . Section title: Background Educational score: 4.058547019958496 Domain: biomedical Document type: Review Language: en Formal treatment guidelines specifically for adults with ADHD have not yet been developed in the U.S . With approximately 30 different FDA-approved stimulants available for providers to choose from, first-line treatment decisions are often the result of trial and error [ 8 – 10 ]. Justifying an initial choice of prescription is further complicated by the variability in treatment responses between patients . Although stimulants are the most effective intervention for ADHD , some patients do not respond well to common frontline medications . A number of clinical factors contribute to heterogeneous treatment effects. Individuals who are older (amongst children), have milder symptoms, and have comorbid anxiety are the least likely to respond well to stimulants . Worse initial symptoms, including inattentiveness and disinhibition, are weak predictors of favorable responses . Treatment non-adherence is related to worse outcomes. Patients are less likely to adhere to treatment if they are younger (< 25 years old), have less than a secondary level of education, lack of family history of ADHD, have lower baseline symptom severity, and perceive lower medication efficacy . Section title: Background Educational score: 3.976501226425171 Domain: biomedical Document type: Study Language: en The rise of precision medicine in psychiatry has underscored the need to identify reliable predictors of treatment response, particularly the tendency to supplement daily medication with IR formulations . Previous studies have shown that ER medications are effective on the group level, but few have sought to find whether individual variability can be attributed to baseline patient characteristics . Variable clinical outcomes likely arise due to complex interactions between patient factors, including baseline psychological profiles and demographics . Demonstrating reduced IR supplementation with a particular medication, regardless of underlying individual variables, would provide a basis on which to make first-line treatment decisions. If ER efficacy is significantly altered depending on a specific patient variable, it would help inform individualized treatment plans. Section title: Background Educational score: 3.794074296951294 Domain: biomedical Document type: Study Language: en Dyanavel XR is an ER amphetamine with a targeted pharmacokinetic profile enabling rapid onset of action with continuous release that prolongs its active duration to allow once-daily dosing . Dyanavel XR leverages its unique technology to optimize the balance between fast onset of effect and maintenance of efficacy throughout the day . In adults, Dyanavel XR improves symptoms and has a safety profile comparable with other approved stimulants . In a large national sample representing 60% of all insurance claims in the U.S., Dyanavel XR was shown to be more frequently used as monotherapy compared to other ER medications . Section title: Background Educational score: 4.087702751159668 Domain: biomedical Document type: Study Language: en The abundance of individual factors with the potential to confound the overall effect of Dyanavel XR on monotherapy rates warrants investigation to determine whether any patient-level variable can explain the effect of Dyanavel XR on rates of IR supplementation. The purpose of the current study was to determine whether Dyanavel XR’s tendency to reduce IR supplementation could be explained by any other individual patient variable. Through a series of predictive analyses using retrospective data from 417 adult patients with ADHD from the Rochester Center for Behavioral Medicine (RCBM), the results aim to provide insights into potential predictive variables for ADHD treatment response. Section title: Study design Educational score: 3.190988302230835 Domain: biomedical Document type: Study Language: en This study is a retrospective cohort analysis of medical treatment records obtained between November 2022 and June 2024. Section title: Participants Educational score: 4.060763359069824 Domain: biomedical Document type: Study Language: en To be included, participants must have had a diagnosis of ADHD, have received treatment for ADHD, be at least 18 years of age or older at the start of treatment, received treatment of at least one extended release (ER) psychostimulant (amphetamine or methylphenidate preparations) for at least six months, and provided consent for secondary research use of their medical treatment data. Participants with a potentially confounding comorbid psychiatric condition, including bipolar spectrum disorders, alcohol and substance use disorders, or an initial Patient Health Questionnaire-9 (PHQ-9) score greater than or equal to 14, were excluded. Participants with a potentially confounding comorbid medical condition, including thyroid conditions, cancer or chemotherapy treatment, sleep disorders, or migraines, were also excluded from the study. Section title: Participants Educational score: 4.13960599899292 Domain: biomedical Document type: Study Language: en A stratified sampling strategy was used, grouping patients by ER medication to target a total of 150 patients for each of the following ER formulations: Dyanavel XR, ER amphetamine (equal numbers of Adderall XR and lisdexamfetamine [Vyvanse]), and ER methylphenidate (equal numbers of Focalin, Concerta, and generic methylphenidate ER). The target sample size was calculated based on a power analysis for structural equation modeling to meet a power of 85% when the root mean square of error of approximation is 0.09 and approximated degrees of freedom is 20 . Patient records were selected randomly for each stratum. After reviewing patient records and excluding those who did not meet the study criteria, there were 143 Dyanavel XR, 131 ER amphetamine (65 Adderall XR and 66 lisdexamfetamine), and 143 methylphenidate (51 Focalin, 53 Concerta, and 39 generic methylphenidate ER) patient records meeting the inclusion criteria. If patients were missing any assessments, their data were included in analyses where possible, but values were excluded if missing. Section title: Procedure Educational score: 2.1015846729278564 Domain: biomedical Document type: Study Language: en Electronic medical records were obtained from Rochester Center for Behavioral Medicine (RCBM), a large outpatient psychiatric practice, which maintains a HIPAA-compliant Qualtrics platform for securely administering patient-facing forms, questionnaires, and psychometrics. The study data elements were retrieved via direct queries to the electronic medical records system’s server and queries to the practice’s Qualtrics system’s electronic storage. Pharmacy data is sent and received through the SureScripts system. Section title: Procedure Educational score: 2.010423421859741 Domain: biomedical Document type: Study Language: en Data were de-identified by compiling the elements onto a single datasheet as they are retrieved, where one row corresponded with one patient. No columns on this data sheet contained any of the 18 identifiers described in the HIPAA privacy rule’s safe harbor provision, ensuring that, to the furthest extent possible after completion of the data sheet, no reidentification of a patient would be possible. The study staff responsible for compiling the datasheet did not retain any records of patient identifiers that may have been consulted in the construction of the study datasheet. No re-identification of a patient was attempted or permitted by the study researchers. Section title: Procedure Educational score: 3.683873176574707 Domain: biomedical Document type: Study Language: en Participants were referred to RCBM prior to treatment by various mental health and medical professionals and completed intake forms prior to their intake appointment. Next, they completed a pre-visit survey prior to each visit through the online survey distribution software, Qualtrics. The pre-visit survey is hosted by RCBM’s Qualtrics platform and is connected with RCBM’s electronic charting program through the Qualtrics API. This API connection allows for a patient’s individual responses to be automatically filed in their chart for clinician review. Their responses are paired with information from the electronic medical record so the clinician can review the patient-reported information in tandem with their medical history and clinician-reported symptom severity ratings from visit to visit. The API also allows the researchers to extract the necessary variables for the current study’s analyses without accessing the electronic medical record system. This analysis compiled data from the pre-visit surveys at baseline and after 90 days of ER treatment. The follow-up time point of 90 days was selected because, in practice, most patients would have had their first follow-up appointment with their prescribing clinician within 90 days . Section title: Patient history and information collected prior to initial visit Educational score: 2.5703935623168945 Domain: biomedical Document type: Study Language: en Prior to their initial visit at RCBM, patients completed intake forms reporting their demographic information, including age, gender, natal sex, employment status, education completed, marital status, and ethnicity. They also self-reported their prescription history prior to RCBM. Clinician-reported information was queried from the electronic medical record database, which included the patients’ prior diagnoses, current diagnoses, and current prescriptions. Section title: Clinician-reported information Educational score: 4.172589302062988 Domain: biomedical Document type: Study Language: en Clinicians completed the Clinical Global Impression (CGI) for patients at each visit . The CGI was developed by the National Institute of Mental Health in collaborative pharmacology trials of schizophrenia to assess illness improvement. Since its origins, it has become a routine measure in psychiatric settings. The scale has three items: Severity of Illness (CGI-S), Global Improvement (CGI-I), and Efficacy Index. CGI-S is a single item rating on a seven-point scale from 1 (“normal”) to 7 (“extremely ill”) asking the clinician to rate the patient’s severity of illness based on their experience with individuals of the same clinical population. The CGI-I is also a single item rating on a seven-point scale from 1 (“very much improved”) to 7 (“very much worse”). The Efficacy Index is a rating of the effect of the therapeutic intervention from 1 (“none”) to 4 (“outweigh therapeutic effect”) . The CGI scale has established utility in the rating of schizophrenia, panic disorder, depression, obsessive compulsive disorder, and social anxiety disorder . It has good concurrent validity and sensitivity to change in patients with panic disorder and depression and performs similarly to other standard outcome measures, including the Health of the Nation Outcome Scales and the Brief Psychiatric Rating Scale . The change between CGI-S score at admission and discharge is highly correlated with the CGI-I at discharge, showing its reliability to interpret changes in disorders . Section title: Patient-reported information Educational score: 3.896904706954956 Domain: biomedical Document type: Study Language: en Patients completed an online survey prior to every clinic visit. The pre-visit survey form includes three psychometric tools: the Patient Health Questionnaire-9 (PHQ-9) , the Generalized Anxiety Disorder-2 (GAD-2) , and the ADHD Symptom and Side Effect Tracking (ASSET) scale . To extract patient data for this analysis, researchers performed a query of patient data from the Qualtrics API. The query included the list of medications being actively managed by RCBM at the time of each visit, the type of treatment provider that the patient saw for the follow up visit and/or their prescribing clinician, and the diagnoses and/or clinical problems the clinician designated as the targets of treatment. Data from pre-visit surveys were also used to calculate the tendency of prescribers to pair an IR stimulant with an ER stimulant, as reported by the patients’ indication of their prescribing clinician and current medications. Section title: PHQ-9 Educational score: 4.070318222045898 Domain: biomedical Document type: Study Language: en The Patient Health Questionnaire (PHQ)-9 is a nine-item self-administered screening tool for depression . Responses are rated on a Likert scale from 0 (“not at all”) to 3 (“nearly every day”) indicating increasing severity of symptoms with a maximum score of 27. Across 14 validation studies conducted in primary care, medical outpatients, and specialty services, the PHQ-9 has high sensitivity (0.80 [95% CI: 0.71–0.87]) and specificity (0.92 [95% CI: 0.88–0.95]) for major depression when scores are greater than or equal to 10 . Section title: GAD-2 Educational score: 4.084649085998535 Domain: biomedical Document type: Study Language: en The Generalized Anxiety Disorder (GAD) scale-2 is a 2-item shortened version of the GAD-7, a seven-item, Likert scale for identifying GAD, with items rated from 0 (“not at all”) to 3 (“nearly every day”) . The GAD-7 has been validated in large samples in primary care, with internal consistency, good test-retest reliability, and high sensitivity (89%) and specificity (82%) for GAD. The GAD-2 was developed as a truncated version of the full questionnaire, only presenting the two questions of the GAD-7 representing the core symptoms of anxiety. With a cutoff score of greater than or equal to three indicating GAD, the GAD-2 scale maintains high sensitivity (86%) and specificity (83%) . Section title: ASSET Educational score: 4.119479179382324 Domain: biomedical Document type: Other Language: en The ADHD Symptom and Side Effect Tracking Scale (ASSET) is a ten item self-report measure for ADHD symptom severity with a companion list of assorted side effects clinicians are advised to track throughout psychopharmaceutical treatment for ADHD. The scale asks the participant to rate the level of the impact on daily life functioning they may have experienced due to problems with the sign or symptom of ADHD referenced by the item (anchors: 1 = no problem present, 6 = severe impact). The ten items are split into two subscales. The Inattentive Subscale includes the items “attention span,” “forgetfulness,” “follow-through,” “trouble organizing tasks and activities,” “misplacing daily items,” and “productivity.” The Hyperactivity and Impulsivity Subscale includes the items “fidgetiness,” “trouble waiting turn/general impatience,” “anxiety,” and “mood”. The scoring of the baseline scale is a factor score calculated as a weighted sum of the ten severity items. A cut score of greater than or equal to 4.40 achieves high sensitivity (80%) and specificity (80%) . A factor score change of 0.75 indicates reliable change . The list of side effects included insomnia, generalized pain, fatigue, dry mouth, poor appetite, food binges, tics, anger, suspiciousness, restless legs, end of dose crash, return of symptoms as dose wears off, and unwanted changes in weight, and were rated on a Likert scale (1 = never, 5 = always). Section title: Statistical analysis Educational score: 3.170656442642212 Domain: biomedical Document type: Study Language: en Baseline patient characteristics from the screening battery and pre-visit survey at their initial and 90-day visits, or the visit closest to 90 days since the start of their ER treatment, are reported. Descriptive results are stratified by whether the patient supplemented their treatment with an IR stimulant at 90 days. For continuous variables, mean, standard deviation, minimum, and maximum values were calculated, and frequency counts and percentages were calculated for categorical variables. Section title: Statistical analysis Educational score: 4.0887980461120605 Domain: biomedical Document type: Study Language: en The relationship between Dyanavel XR stimulant use and the tendency to supplement with IR stimulants was assessed by a crosstabulation with Z-tests for independent proportions. This analysis excluded patients who had used IR medications at baseline. Because Dyanavel XR was uniquely associated with a reduction in IR use at 90 days, the other medications (Adderall XR, Vyvanse, Focalin, and Methylphenidate ER) were collapsed into a single group, and Dyanavel XR use was coded into a binomial variable (Dyanavel XR = 1, other ER medication = 0). To account for IR stimulant use at baseline, an ANCOVA was conducted using Dyanavel XR as the predictor variable and IR at baseline as the covariate. Section title: Statistical analysis Educational score: 3.8907482624053955 Domain: biomedical Document type: Study Language: en Independent relationships between each patient variable and IR supplementation rate were assessed using point-biserial Pearson correlations for continuous variables and binomial regressions for categorical variables. Section title: Statistical analysis Educational score: 4.094799041748047 Domain: biomedical Document type: Study Language: en To determine if any factors related to the patient, treatment, side effects, and treatment responses mediated this relationship between Dyanavel XR use and IR use at 90 days, backward stepwise linear regressions were modeled using variable groupings determined a priori in alignment with hypothesized predictive variables, and with IR use at 90 days as the outcome variable. The predictor variable groupings were: (1) side effects reported at baseline, (2) side effects reported after 90 days, and (3) change in symptoms from baseline to 90 days using assessment scale scores (ASSET, CGI-S, CGI-I, GAD-2, and PHQ-9). Section title: Statistical analysis Educational score: 3.693873643875122 Domain: biomedical Document type: Study Language: en All variables in the group were included in the initial regression analysis. At each step, the variable with the lowest level of significance was removed, and the regression was performed again using the remaining variables. This process was repeated until all variables satisfied the significance condition ( p < .05). The analyses met the assumptions of linearity, independence, and normality of residuals. Section title: Participant demographics and baseline characteristics Educational score: 2.0365405082702637 Domain: biomedical Document type: Study Language: en The total sample included 417 patients (age: M = 36.0 years, SD = 13.5, range = 18–81). Most patients were female ( n = 280, 67.3%) and white ( n = 399, 95.9%). Employment status, marital status, and education completed were also collected when possible (Table 1 ). Section title: Participant demographics and baseline characteristics Educational score: 2.45275616645813 Domain: biomedical Document type: Study Language: en Table 1 Baseline demographics Patients ( N = 416) Age in years, mean (SD) 36.04 (13.47) Gender, n (%) Male 135 (32.5%) Female 280 (67.3%) Non-binary 1 (0.2%) Race, n (%) Black 5 (1.2%) Asian 1 (0.2%) White 399 (95.9%) Other 6 (1.6%) Employment Status, n (%) College Student 8 (1.9%) Employed Full Time 125 (30%) Employed Part Time 14 (3.3%) Retired 2 (0.5%) Disabled 2 (0.4%) Student (other) 21 (5.0%) Unemployed 10 (2.4%) No Data 234 (56.3%) Marital Status, n (%) Divorced 9 (2.2%) Engaged 5 (1.2%) Married 170 (40.9%) Partnered 2 (0.5%) Separated 2 (0.5%) Single 183 (44.0%) Widowed 2 (0.5%) Missing 43 (10.4%) Education Completed, n (%) High school 13 (3.1%) Undergraduate 104 (24.7%) Graduate 21 (4.0%) Middle school 1 (0.2%) Some college 27 (12.7%) Missing 255 (60.6%) Section title: Effects of Dyanavel XR on IR supplementation at 90 days compared to other ER medications Educational score: 3.81902813911438 Domain: biomedical Document type: Study Language: en A linear regression was performed to determine the relationship between IR at baseline and the addition of IR supplementation at 90 days. Overall, IR use at baseline was a significant predictor of IR supplementation at 90 days ( R 2 = 0.552). Section title: Effects of Dyanavel XR on IR supplementation at 90 days compared to other ER medications Educational score: 4.073134899139404 Domain: biomedical Document type: Study Language: en Due to the overall effect of baseline IR, an exploratory analysis was conducted excluding patients who had used IR medications at baseline to determine if Dyanavel XR had a unique effect on the need to supplement with IR medication compared to other ER medications. Results of a cross-tabulation with Z-tests for independent proportions within each ER medication indicated that few patients ( n = 23) on any ER medication supplemented with an IR at 90 days. Dyanavel XR was the only ER medication that significantly reduced IR supplementation at 90 days (no IR added: n = 140; IR added:, n = 3; p < .05). Section title: Effects of Dyanavel XR on IR supplementation at 90 days compared to other ER medications Educational score: 4.13765811920166 Domain: biomedical Document type: Study Language: en Because Dyanavel XR was uniquely associated with a reduction in IR use at 90 days, the other medications (Adderall XR, Vyvanse, Focalin, and Methylphenidate ER) were collapsed into a single group, and Dyanavel XR use was coded into a binomial variable (Dyanavel XR = 1, other ER medication = 0). To account for IR use at baseline, an ANCOVA was conducted using Dyanavel XR as the predictor variable and IR at baseline as the covariate. As expected, the use of IR medication at baseline was associated with the addition of IR at 90 days of treatment ( F 1,413 = 5.86, p = .016). Controlling for IR use at baseline, there was a significant effect of Dyanavel on IR at 90 days ( F 1,413 = 4.67, p = .031), with Dyanavel XR being associated with reduced IR use. Section title: Predictive variables impacting dyanavel XR’s effect on IR supplementation at 90 days Educational score: 4.021987438201904 Domain: biomedical Document type: Study Language: en Of the patients who added an IR stimulant at 90 days, their prescribers had an average IR-prescribing tendency of 22.6%, and of patients who did not add an IR at 90 days, their prescribers had an average IR-prescribing rate of 27.3%. At baseline and at 90 days, patients took ASSET, GAD-2, and PHQ-9 tests, and their clinicians completed CGI-S and CGI-I scales (for descriptive statistics of assessment outcomes, see Table 2 ). Regardless of whether patients added an IR medication at 90 days, ASSET scores improved over the 90-day time period, but the effect was stronger in patients who supplemented with an IR medication (Table 3 ). Section title: Predictive variables impacting dyanavel XR’s effect on IR supplementation at 90 days Educational score: 4.076171875 Domain: biomedical Document type: Study Language: en Table 2 Descriptive statistics: patients with and without IR supplementation at 90 days a Variable n Min Max Mean SD Patients with IR supplementation at 90 days Time in Treatment Prior to ER (Days) 23 0.08 4761.07 746.11 1109.78 Baseline ASSET 23 0.98 5.44 3.76 1.21 PHQ-9 23 0 24 6.43 5.88 GAD-2 23 0.00 6.0 1.57 1.59 CGI-S 21 2 5 3.67 0.66 CGI-I 20 1 4 2.10 0.79 90 days ASSET 23 0.97 5.02 3.00 0.98 PHQ-9 23 0 23 5.61 5.37 GAD-2 23 0.00 6.00 1.91 2.11 CGI-S 21 3 4 3.57 0.51 CGI-I 20 1 4 2.15 0.67 Valid N (listwise) 17 Patients without IR supplementation at 90 days Time in Treatment Prior to ER (Days) 393 0.021435 4745.88 989.10 1164.93 Baseline ASSET 385 0.00 5.98 3.50 1.19 PHQ-9 392 0 21 7.08 4.68 GAD-2 393 0.00 6.00 1.93 1.55 CGI-S 371 2 6 3.83 0.76 CGI-I 360 1 6 2.81 1.13 90 days ASSET 385 0.00 5.88 3.12 1.08 PHQ-9 392 0 24 5.65 4.36 GAD-2 393 0.00 6.00 1.68 1.47 CGI-S 371 1 6 3.71 0.82 CGI-I 360 1 5 2.57 0.97 Valid N (listwise) 313 ASSET, ADHD Symptom and Side Effect Tracking; CGI-S, Clinical Global Impressions-Severity; CGI-I, Clinical Global Impressions-Improvement; ER, extended release; GAD-2, Generalized Anxiety Disorder 2-Item; PHQ-9, Patient Health Questionnaire-9 a The visit falling closest to 90 days after ER stimulant was prescribed Section title: Predictive variables impacting dyanavel XR’s effect on IR supplementation at 90 days Educational score: 4.154795169830322 Domain: biomedical Document type: Study Language: en Table 3 Magnitude of the change from baseline in psychometric assessments in patients with and without IR supplementation at 90 days a Change from baseline n Min Max Mean SD Cohen’s d b Patients with IR supplementation at 90 days ASSET 23 -1.68 2.91 0.7570 1.11 0.68 PHQ-9 23 -10.00 18.00 0.8261 5.04 0.16 GAD-2 23 -6.00 1.00 − 0.3478 1.47 0.24 CGI-S 21 -2.00 1.00 0.0952 0.62 0.15 CGI-I 20 -1.00 1.00 − 0.0500 0.51 0.10 Patients without IR supplementation at 90 days ASSET 385 -2.60 4.12 0.3858 0.98 0.39 PHQ-9 392 -14.00 15.00 1.4311 4.11 0.34 GAD-2 393 -6.00 5.00 0.2468 1.48 0.17 CGI-S 371 -2.00 3.00 0.1186 0.65 0.18 CGI-I 360 -3.00 4.00 0.2361 1.07 0.22 ASSET, ADHD Symptom and Side Effect Tracking; CGI-S, Clinical Global Impressions-Severity; CGI-I, Clinical Global Impressions-Improvement; ER, extended release; GAD-2, Generalized Anxiety Disorder 2-Item; PHQ-9, Patient Health Questionnaire-9 a The visit falling closest to 90 days after ER stimulant was prescribed b Indicating the magnitude of the change from baseline (small: Cohen’s d = 0.2, medium: Cohen’s d = 0.5, large: Cohen’s d ≥ 0.8) Section title: Predictive variables impacting dyanavel XR’s effect on IR supplementation at 90 days Educational score: 3.9864611625671387 Domain: biomedical Document type: Study Language: en The binary variable indicating whether the patient was prescribed Dyanavel XR or another ER was significantly associated with IR supplementation at 90 days (χ 2 = 4.320, Nagelkerke R 2 = 0.039, p = .038). No other continuous (Table 4 ) or categorical (Table 5 ) variable was associated with IR supplementation. Section title: Predictive variables impacting dyanavel XR’s effect on IR supplementation at 90 days Educational score: 4.203016757965088 Domain: biomedical Document type: Study Language: en Table 4 Point-biserial Pearson correlations demonstrating the relationship between each continuous variable and the addition of IR medication at 90 days. Treatment responses representing a change in score between baseline and 90 days were Z-transformed prior to analysis Variable Group Variable Description Pearson correlation coefficient ( r ) R 2 p Demographics Age Age in Years 0.02 0.00032 0.716 ER Prescription Decision Tendency to Prescribe ER Integer Value: % of patients with an ER prescription − 0.10 0.0090 0.07 Time in Treatment Prior to ER Integer Value − 0.05 0.0023 0.33 Assessment scores at baseline ASSET ADHD symptoms in terms of daily life functioning impact at the time of visit 0.050 0.0025 0.31 PHQ-9 Severity of depressive symptoms in terms of frequency at the time of visit − 0.03 0.00096 0.53 GAD-2 Severity of anxious symptoms in terms of frequency at the time of visit − 0.05 0.0028 0.28 CGI-S Global severity of the overall presentation assessed by the clinician at the time of visit − 0.05 0.0023 0.34 CGI-I Global improvement of the overall presentation assessed by the clinician − 0.14 0.020 0.01 Assessment scores at 90 days a ASSET Severity of ADHD symptoms in terms of daily life functioning impact − 0.03 0.00063 0.62 PHQ-9 Severity of depressive symptoms in terms of frequency − 0.00 0.000004 0.96 GAD-2 Severity of anxious symptoms in terms of frequency 0.04 0.0013 0.47 CGI-S Global severity of the overall presentation assessed by the clinician − 0.04 0.0014 0.45 CGI-I Global improvement of the overall presentation assessed by the clinician − 0.10 0.0096 0.06 Treatment response (Change in clinical assessments from baseline to 90 days a) Change in ASSET Change of severity of ADHD symptoms in terms of daily life functioning impact 0.09 0.0074 0.08 Change in PHQ-9 Change of severity of depressive symptoms − 0.03 0.0011 0.50 Change in GAD-2 Change of severity of anxiety symptoms − 0.09 0.0083 0.06 Change in CGI-S Change of global severity of the overall presentation assessed by the clinician − 0.05 0.00086 0.34 ASSET, ADHD Symptom and Side Effect Tracking; CGI-S, Clinical Global Impressions-Severity; CGI-I, Clinical Global Impressions-Improvement; ER, extended release; GAD-2, Generalized Anxiety Disorder 2-Item; PHQ-9, Patient Health Questionnaire-9 a The visit falling closest to 90 days after ER stimulant was prescribed Section title: Predictive variables impacting dyanavel XR’s effect on IR supplementation at 90 days Educational score: 4.162461757659912 Domain: biomedical Document type: Study Language: en Table 5 Binomial regressions demonstrating the relationship between each categorical variable and the addition of IR medication at 90 days Variable Group Variable Wald statistic (χ 2 ) Nagelkerke R 2 p ER Prescription Number of ERs previously attempted 1.40 0.011 0.24 ER Prescription category (Dyanavel XR, AMP ER Stimulants, or MPH ER Stimulants) 2.40 0.017 0.12 ER Prescription category (pooled; Dyanavel XR or all other ER stimulants) 4.32 0.039 0.04 Side effects at baseline a Insomnia 0.06 0.000 0.81 Generalized Pain 0.06 0.000 0.80 Dry mouth 0.54 0.004 0.46 Poor Appetite 2.07 0.016 0.15 Food Binges 0.39 0.003 0.53 Tics 0.00 0.000 0.96 Anger 0.06 0.000 0.81 Suspiciousness 0.63 0.005 0.43 Restless Legs 0.28 0.002 0.60 End of Dose Crash b 2.12 0.005 0.15 Return of Symptoms as Medication Wears Off 3.55 0.057 0.06 Side effects at 90 days a, c Insomnia 0.12 0.001 0.73 Generalized Pain 0.33 0.002 0.57 Dry mouth 2.5 0.020 0.12 Poor Appetite 0.24 0.002 0.63 Food Binges 0.05 0.000 0.83 Tics 0.09 0.001 0.76 Anger 2.33 0.018 0.13 Suspiciousness 0.24 0.002 0.60 Restless Legs 0.67 0.005 0.41 End of Dose Crash b 2.22 0.015 0.14 Return of Symptoms as Medication Wears Off 2.90 0.046 0.09 ER, extended release a Patient-rated Likert scales of how often the side effect was experienced in the past two weeks b Answered only if on ADHD medications c The visit falling closest to 90 days after ER stimulant was prescribed Section title: Backward elimination stepwise regression Educational score: 4.124948024749756 Domain: biomedical Document type: Study Language: en The backward elimination stepwise regression started with 11 side effects reported at baseline (generalized pain, insomnia, fatigue, dry mouth, poor appetite, food binges, tics, anger, suspiciousness, restless legs, and end of dose crash) determined to be potential predictors of supplemental IR use at 90 days, as inadequate symptom management and side effects are key reasons for augmenting treatment in adults . The initial regression was not significant ( F 11,376 = 0.690, p = .748). After the backward elimination procedure, the model did not reach significance with any predictor variable. Section title: Backward elimination stepwise regression Educational score: 4.142637252807617 Domain: biomedical Document type: Study Language: en In another stepwise regression of the same 11 side effects reported at 90 days, the initial model was not significant ( F 11,376 = 0.841, p = .599). After backward elimination, the model trended to significantly predict IR supplementation at 90 days ( F 13,387 = 2.55, p = .055) when including the predictor variables dry mouth ( t = -1.61, p = .11), anger ( t = -1.44, p = .15), and end of dose crash ( t = 1.97, p = .050), with end of dose crash significantly predicting IR use at 90 days. Continuing the stepwise elimination resulted in a failure of any predictor to reach statistical significance (all p > .05). Section title: Backward elimination stepwise regression Educational score: 4.136570453643799 Domain: biomedical Document type: Study Language: en The regression including the change in CGI-S, CGI-I, ASSET, GAD-2, and PHQ-9 scores from baseline to 90 days was significant ( F 5,365 = 3.07, p = .010), indicating that the change in at least one assessment score affected IR use at 90 days. Change in CGI-S ( t = 0.59, p = .95), CGI-I ( t = -1.17, p = .25), and PHQ-9 ( t = 0.21 p = .83) were not significant predictors of IR supplementation at 90 days. Change in ASSET scores, indicating worsened ADHD symptom presentation, and change in GAD-2 scores, indicating worsened anxiety, predicted greater IR use at 90 days (ASSET: t = 3.01, p = .003; GAD-2: t = -2.38, p = .018). Section title: Backward elimination stepwise regression Educational score: 4.101319789886475 Domain: biomedical Document type: Study Language: en After identifying worsened ASSET and GAD-2 measures as significant positive predictors of IR use at 90 days, the next analysis sought to determine if Dyanavel XR could refine the predictive model. With the three predictor variables of change in ASSET, change in GAD-2, and Dyanavel XR, the model still significantly predicted IR use at 90 days ( F 3,404 = 4.81, p = .003), and all variables were significant predictors (ASSET change: t = 2.377, p = .018; GAD-2 change: t = -2.543, p = .011; Dyanavel XR: t = -2.112, p = .035). This demonstrates that together, improved ADHD symptoms and improved anxiety, in addition to being on Dyanavel XR, was associated with reduced IR use at 90 days. Section title: Path analysis Educational score: 4.0526018142700195 Domain: biomedical Document type: Study Language: en Structural equation models and path analyses were planned to determine the relationships between significant variables. However, the results did not yield sufficient independently significant variables to attempt an adequately-powered analysis. In lieu of a complete analysis, the results prompted an exploratory path analysis to determine whether the relationship between Dyanavel XR and reduced IR supplementation at 90 days was explained in part by the relationship between the end of dose crash and IR supplementation. The path analysis shows that Dyanavel XR independently reduced the occurrence of end of dose crash and reduced IR supplementation. However, end of dose crash was not significantly associated with IR supplementation, demonstrating that the effect of Dyanavel XR on IR supplementation is not explained by its tendency to mitigate end of dose crashes . Section title: Path analysis Educational score: 3.7900474071502686 Domain: biomedical Document type: Study Language: en Table 6 Path analysis showing relationships between Dyanavel, end of dose crash, and IR supplementation at 90 days Regression weights Estimate SE CR p End of dose crash a ← Dyanavel XR − 0.35 0.11 -3.30 < 0.001 IR supplementation ← End of dose crash a 0.01 0.01 1.22 0.22 IR supplementation a ← Dyanavel XR − 0.05 0.02 -2.03 0.04 CR, critical ratio; IR, immediate release; SE, standard error; XR, extended release a At the time of visit falling closest to 90 days after ER stimulant was prescribed Section title: Path analysis Educational score: 2.4164087772369385 Domain: biomedical Document type: Study Language: en Fig. 1 Path model showing the effects of Dyanavel and end of dose crash at 90 days on the addition of an IR stimulant at 90 days. The 90-day time point indicates the visit falling closest to 90 days after the ER stimulant was prescribed Section title: Discussion Educational score: 4.114020824432373 Domain: biomedical Document type: Study Language: en With the tremendous heterogeneity in the patient population with ADHD, different treatments may interact with individual patient characteristics and modify the effect of therapies on patient outcomes . The present analyses aimed to determine whether a specific ER amphetamine stimulant, Dyanavel XR, was uniquely associated with the likelihood of patients supplementing ER treatment with an IR medication. The results show that over 90 days of treatment, compared to other ER amphetamines and ER methylphenidates, patients who were prescribed Dyanavel XR were less likely to supplement with IR formulations. Importantly, the association between Dyanavel XR and reduced IR supplementation was not explained by any other baseline patient variable measured here, but it was related to their change in ADHD and anxiety symptoms over 90 days. Section title: Discussion Educational score: 4.118409156799316 Domain: biomedical Document type: Study Language: en The analyses also showed that patients who used IR medications at baseline were more likely to supplement with an IR medication at 90 days, regardless of which ER medication they were prescribed. Dyanavel XR was distinct from the other ER stimulants because it maintained an association with reduced IR supplementation even when controlling for patients’ use of IR medications at baseline. Previous studies have shown that patients taking ER stimulants have greater treatment adherence and are less likely to switch to or augment with a medication of a different release method [ 3 – 5 , 37 ]. In a retrospective claims database analysis from 2010, patients taking ER amphetamines (Adderall XR, Dexedrine Spansules, or Vyvanse) had better treatment adherence and persistence than those taking ER methylphenidates (Concerta, Daytrana, or Focalin XR), but were equally likely to augment with IR medications . This is consistent with the present results showing that only Dyanavel XR reduced the tendency to supplement with an IR medication. These results distinguish Dyanavel XR from other ER amphetamines in its potential to be used as monotherapy. Section title: Discussion Educational score: 4.154104232788086 Domain: biomedical Document type: Study Language: en After confirming that Dyanavel XR reduced IR supplementation at 90 days, subsequent analyses investigated whether patient variables could better explain this association. The analyses did not reveal an impact of side effects reported at baseline on IR supplementation. Of the side effects reported at the 90-day visit, there was a trend to predict IR supplementation when the regression model was reduced to include only dry mouth, anger, and end of dose crash. In this model, the only significant predictor of IR use at 90 days was the frequency of experiencing an end of dose crash. Certainly, patients value medications with a longer duration of effect, shorter speed of onset, and reduced side effects . Although reducing the risk of an end of dose crash, or rebound effect after medication wears off, is less important to patients than reducing headaches, insomnia, and mood changes, it is still considered an important factor . Additionally, dose augmentation strategies are typically implemented when patients desire symptom management for longer than the typical 10–12 h achievable with ER medications and want to avoid rebound effects . The results here are consistent with the literature showing that some side effects, especially rebound after a dose wears off, would lead patients to augment their daily treatment . However, interpretation of this regression model is limited because the relationship was not strong and was driven by the effect of end of dose crash. Section title: Discussion Educational score: 4.14072322845459 Domain: biomedical Document type: Study Language: en Patients’ response to treatment regarding their anxiety and ADHD symptoms predicted their likelihood of supplementing with an IR medication. The present analysis found that patients who were taking Dyanavel XR whose anxiety and ADHD symptomatology improved over 90 days were less likely to supplement with IR medication. Given that anxiety is highly comorbid with ADHD, it is important to consider the effects one treatment may have on the presentation of both disorders . Some patients experience anxiety as a side effect of ADHD medications, and anxiety is one of the most common complications causing patients to discontinue their treatment . Long-term improvements in anxiety and ADHD, along with being on Dyanavel XR, reduces the tendency to supplement with IR medication, which supports the impact of Dyanavel XR on maintaining monotherapy and improving quality of life. Section title: Discussion Educational score: 4.079131603240967 Domain: biomedical Document type: Study Language: en The present results reflect the heterogeneous nature of ADHD in the general population and could thus be confounded by variability due to genetic and environmental factors that were not measured in this study. Differences in which symptoms manifest and persist, as well as their severity, have been linked to prenatal and postnatal experiences related to maternal health, stressors during pregnancy, and psychosocial childhood adversity . Exposure to harmful chemicals, toxins, and poor nutrition may also contribute to dysregulated neurobehavioral systems and give rise to ADHD-related symptoms . As such, the etiology of ADHD is complex and relies on an interaction between inherited genetic traits, divergent neurobiology, and environmental risk factors that could not be fully captured with the study design presented here. Section title: Discussion Educational score: 4.058389186859131 Domain: biomedical Document type: Study Language: en The clinical manifestation of ADHD may also vary over time within the same individual, as previous research has noted differences in which symptoms are likely to characterize the disorder depending on age . ADHD is traditionally thought of as a childhood disorder, but diagnoses amongst adolescents and young adults have become more common, in part due to the recognition that symptoms can fluctuate across development . For example, restlessness, aggression, and disruptive behaviors are more common in young children, whereas inattention tends to persist as people get older . Additionally, age has been linked to treatment patterns, including initiation, switching, and discontinuation . The present results showed that age at the start of the study was not significantly associated with IR supplementation at 90 days. Given the wide range of ages included from 18 to 81 years old, the age at which symptoms first appeared and age at first treatment initiation could have an effect, but the de-identified dataset precluded access to such historical data. Therefore, a direct investigation of how age at diagnosis, age at treatment initiation, and other demographic and environmental risk factors affect treatment responses would be a logical step for future research. Section title: Discussion Educational score: 3.9872496128082275 Domain: biomedical Document type: Study Language: en Several additional limitations should be considered in the interpretation of these results. As an observational study, the patient population was sampled to achieve balanced groups of current ER medications, but could not account for the heterogeneity in patients’ medication history. The patient population also lacked diversity, with most patients being white and having obtained at least an undergraduate degree, limiting our external validity. Additionally, relatively few patients in this sample added an IR medication at the 90-day visit, limiting analytical power to detect smaller effect sizes of patient-level variables that could be influencing IR supplementation. Future studies would benefit from the inclusion of a control group of patients who did not receive an ER medication. Because this was a non-experimental study using observational data from a given timeframe, there was a paucity of data available for individuals who were not treated medically. Section title: Discussion Educational score: 3.9454257488250732 Domain: biomedical Document type: Study Language: en Importantly, there was no significant difference in prescriber tendencies between the patients who did and did not add an IR medication, with both groups seeing clinicians who prescribed IR medications approximately one-fourth of the time. This rules out the potential that clinician biases were driving the results. However, longer-term follow-up would clarify whether Dyanavel XR prevents IR supplementation or delays it. Finally, these analyses relied on subjective psychometric tests for depression, anxiety, and ADHD, ratings of side effects, and clinician measures of improvement. Although these rating scales have been well-validated, psychiatry is always aiming to improve the reliability and validity of such measures . Section title: Discussion Educational score: 4.114927291870117 Domain: biomedical Document type: Study Language: en ER stimulants are a first-line option for adults with ADHD because they lead to better treatment adherence and reduce the risk of misuse compared to IR formulations . Still, some clinicians advise patients to supplement with an IR medication later in the day to ensure symptoms can be managed . For adults who have responsibilities throughout the day, effective ER medications that can be reliable as monotherapy are preferred. Dyanavel XR utilizes a unique mechanism of sustained release, which resulted in an efficacy duration of up to 13 h in the double-blind clinical trials in children and adults . While direct comparisons are not possible without head-to-head clinical trials, the statistical analyses presented here using retrospective patient data support the benefit of Dyanavel XR in reducing the need to supplement with an IR medication, regardless of IR supplementation at baseline. Despite its limitations, this study contributes to the growing literature demonstrating the value of precision medicine in ADHD treatment. Although treating ADHD is complicated by the wide range of symptoms and responses shown in patients, predictive analyses, such as those shown here, can be translated to clinical care. Additional real-world investigations should be conducted to determine whether individual variables can predict treatment efficacy to promote data-driven individualized treatment plans for ADHD. Section title: Conclusions Educational score: 3.85164475440979 Domain: biomedical Document type: Study Language: en Adults with ADHD desire consistent and extended symptom management without the need for multiple, supplementary medications. The current research shows that Dyanavel XR is uniquely associated with reductions in the tendency to supplement daily ER treatment with IR medications. Dyanavel XR and reduced IR supplementation were also related to improvements in ADHD and anxiety symptoms over a 90-day period. Clinicians may consider these results when making treatment decisions with their adult patients with ADHD. | Review | biomedical | en | 0.999999 |
PMC11697941 | Section title: Introduction Educational score: 4.130533695220947 Domain: biomedical Document type: Other Language: en Direct pulp capping (DPC) is one of the most conservative vital pulp therapy (VPT) techniques aims at protecting the pulp tissue in healthy status in terms of maintaining the integrity of the vascular and neural supply in the dentin-pulp complex as well as supporting the immune defence mechanism of the dental pulp . DPC involves the application of a biocompatible dressing material over an injured pulp to prompt the regenerative power of human dental pulp cells (HDPCs) required for the healing process . The standards of optimal DPC material include biocompatibility, preventing microleakage, positive antimicrobial activity, and the bioinductive power of a calcified barrier with highly qualified properties . Section title: Introduction Educational score: 3.7790446281433105 Domain: biomedical Document type: Study Language: en Several factors are affecting the decision-making of DPC procedures. According to the recent data gathered from a multinational survey from sixteen countries , pulp exposure resulting from carious lesions is the most significant determinant in clinical decisions regarding DPC. Other prognostic factors included the location of exposure, with dental practitioners showing a higher tendency to perform DPC for occlusally located caries compared caries located on the axial surfaces. Section title: Introduction Educational score: 4.520101070404053 Domain: biomedical Document type: Review Language: en Mineral trioxide aggregate (MTA) is still the benchmark capping agent because of its excellent physiochemical characteristics in terms of its effective potential for dentinogensis and its ability to cause less pulpal inflammation . Additionally, the high success rate results of several clinical trials boost the reliability of MTA as a capping material in VPT, especially DPC . However, there are some negative issues regarding the use of MTA. These drawbacks include prolonged duration required for setting, inadequate adhesion to the dentin, inconsistent mix and handling difficulties, the possibility of crown discoloration, toxicity due to bismuth leaching that has a negative impact on the cell viability, and the concerns that have been raised about the potential leakage of arsenic, its little bioinductive properties, and the high cost [ 9 – 11 ]. One of the major disadvantages of hydraulic calcium silicate cement such as MTA is the color change, especially in the medium and long term in contact with blood, because due to its radio-opacifier bismuth oxide, which is oxidized or reduced upon exposure to oxidizing agents including dentin collagen and sodium hypochlorite . Minimizing the diffusion of bismuth ions into the dentin tooth structure through dentinal tubule blockage using dentin bonding agents and applying a layer of glass ionomer linear can be effective in reducing coronal discoloration . Other strategies to reduce the crown discoloration include modifying the composition of gray MTA by eliminating metallic oxide components producing white MTA. However, tooth crowns still suffer from some degree of discoloration . Color alteration becomes worse in the presence of blood due to the higher blood absorption and subsequent hemolysis of MTA because it remains porous for a longer period . Therefore, MTA should be placed 2−3 mm below the cementoenamel junction . Another approach is modifying the powder of white MTA by the addition of zinc oxide or aluminum fluoride . The introduction of new hydraulic calcium silicate cement in which bismuth oxide is replaced with other radiopacifiers such as zirconium oxide in Biodentine and tantalum peroxide in bioaggregate . Section title: Introduction Educational score: 2.953213930130005 Domain: biomedical Document type: Other Language: en Another problem associated with MTA is the need for delayed setting time (2 h and 45 min) within a hydrated media. Therefore, the need for an extra appointment is required for final restoration placement . New calcium silicate-based cements, such as Biodentine, which permits immediate bonding procedures . Section title: Introduction Educational score: 4.205721855163574 Domain: biomedical Document type: Study Language: en Accordingly, searching for capping material with higher qualities is still mandatory and represents a challenge for researchers. Sodium hexametaphosphate (SHMP) is a candidate of inorganic polyphosphates (poly[P]) . Poly(P) are linear polymers that are located in various body cells and consist of orthophosphate (Pi) residues connected with highly energetic bonds . Poly(P) has a significant role in the differentiation and maturation of osteoblasts, reflecting its osteoinductive potential and osseous calcification and prompting differentiation of human gingival fibroblasts . The odontogenic power of poly(P) compounds such as SHMP to induce proliferation and differentiation of odontoblast-like cells was postulated in two previous in vitro studies . The first tested the effect of two poly(P) candidates, SHMP and sodium triphosphate (STP), on the regenerative potential of HDPCs . The increase in cell count, alkaline phosphatase (ALP) activity, differentiation markers such as osteonectin, osteopontin (OPN), and osteocalcin (OCN), and the angiogenic factors in HDPCs indicated the capability of SHMP and STP in inducing HDPC proliferation and differentiation into odontoblast-like cells. The other study tested the role of matrix metalloproteinase (MMP)−3 on the growth and maturation of odontoblast-like cells . It was found that poly(P) induces odontoblastic biomarkers such as ALP, dentin sialophosphoprotein (DSPP), and dentin matrix protein-1 (DMP-1) mRNA that induce precipitation of osseous deposits. Accordingly, SHMP can be used in regenerative endodontic procedures. Section title: Introduction Educational score: 4.104783058166504 Domain: biomedical Document type: Study Language: en Until now, no in vivo study has been conducted to evaluate the biocompatibility and bioinductive potential of poly(P) on exposed dental pulp tissues. Therefore, the current study aimed to evaluate the histological and radiographic influence of SHMP as DPC agents in young permanent dogs' premolars. The null hypotheses ( H 0 ) of the current study suggested no histological (primary outcome) or radiographic differences (secondary outcome), respectively, between SHMP and MTA as capping materials in DPC immature dogs' teeth. Section title: Animal model Educational score: 2.1149446964263916 Domain: biomedical Document type: Study Language: en The work has been reported in line with the ARRIVE guidelines 2.0. A summary of the study steps according to the PRIASE flowchart was illustrated as Fig. 1 . Section title: Animal model Educational score: 1.9731136560440063 Domain: biomedical Document type: Study Language: en Fig. 1 PRIASE flowchart of the study Section title: Animal model Educational score: 3.4226291179656982 Domain: biomedical Document type: Study Language: en Animals were housed in standard individual cages with an adequate daily amount of food and water ad libitum. Parasiticide of 1 mL/50 kg of Ivermectin (Ivomec supra® 1% injection, Merial, USA) administered subcutaneously. On the day of operation and after weighting each dog, an intravenous cannula (20 gauges) was placed in the recurrent tarsal (saphenous) vein. Section title: Study design, sampling and randomization Educational score: 4.132219314575195 Domain: biomedical Document type: Study Language: en A split-mouth study design included a total of 36 premolars of three healthy 4-month-old Mongrel dogs (two males and one female) weighing approximately 7−9 kg. The number of teeth was calculated using a G*Power 3.1.9.4 after considering a medium effect size of the dependent means of the induced calcified bridge thickness after capping with the two materials. At a 5% alpha level of significance and a power of 80%, a total of 36 teeth were required. Teeth were assigned to either the right or left side of the jaw and were randomly treated with SHMP (intervention group, included 18 teeth) or MTA (control group, included 18 teeth) using a simple randomization approach. DPC was performed via traumatic exposure of sound immature maxillary and mandibular premolars of dogs (expect the fourth maxillary and mandibular premolars) with no apparent coronal or radicular developmental anomalies that have been confirmed with periapical radiographs. Section title: Surgical procedures Educational score: 4.165331840515137 Domain: biomedical Document type: Study Language: en Food and water were held for 12 and 6 h before induction of anesthesia. Each dog was weighed to calculate the dosage of the drug, then a butterfly cannula (winged infusion set gauge 20) was inserted into the recurrent tarsal (saphenous) vein. Dogs were then premedicated by a slow intravenous administration of 1 mg/kg of xylazine HCl (Xyla-ject; ADWIA Co. New Cairo, Egypt) diluted in 3 ml saline. Ten minutes later, anaesthesia was induced by intravenous 10 mg/kg Ketamin HCl (Ketamine®; Hamelin, UK) and maintained by 24 mg/kg propofol (Diprivan® 10 mg/ml, Aspen Pharma, South Africa) at a dose of at a constant rate of infusion using an infusion pump. The dose of propofol was calculated and diluted in a net volume of 200 mg of sterile normal sterile saline and was infused at a rate of 100 mL per hour. Section title: Postoperative care Educational score: 3.703009843826294 Domain: biomedical Document type: Other Language: en Cefotaxime sodium (Cefotax® 500 mg vial, Abbott, USA) antibiotic was injected intramuscularly (IM) once daily for three days with a dosage rate of 50 mg/kg. Intramuscular injection of 7.5 mg of meloxicam (Mobitil® 15 mg ampule, Medical Union Pharmaceuticals, Ismailia, Egypt) were given twice a day as a non-steroidal anti-inflammatory and analgesic medication. Additionally, for three days, Povidine Iodine mouthwash and gargle (Betadine® Mundipharma, Dublin, Ireland) was administered twice a day as an oral antibacterial. Operated animals were followed up during and after the recovery period of anesthesia by well-trained animal caretakers at the veterinary medicine clinic of the local institution. The animals were examined on a regular basis to make sure they had a sufficient and healthy appetite and that all clinical parameters and vital signs (heart rate, pulse, temperature of the rectal area, breathing rate, urine, and excrement) were within normal ranges. Section title: Method of euthanasia Educational score: 4.0651092529296875 Domain: biomedical Document type: Study Language: en After three months, a butterfly cannula (winged infusion set, gauge 20 gauge) was insteted into the recurrent tarsal (saphenous) vein for each dog, then they were euthanized by I.V. injection of xylazine at a dose of 1 mg/kg (Xyla-ject® 50 ml solution, ADWIA Co., new Cairo, Egypt). After that the dogs became less conscious, one-shot I.V. injection of thiopental sodium was injected (10 mg/kg; 25% solution) (thiopental-sodium® 500 mg vial, Epico, Egypt) which introduced the animals into deep irreversible anesthesia that ended by their death. Section title: Method of euthanasia Educational score: 3.196321725845337 Domain: biomedical Document type: Study Language: en Considering a split mouth design, each dog's maxillary and mandibular jaw halves were randomly treated with SHMP or MTA (18 premolars per group). Section title: Pulp capping procedures Educational score: 4.109886646270752 Domain: biomedical Document type: Study Language: en Before starting the clinical procedures, all teeth were radiographically checked for maturity or any root abnormalities. After anesthesia and tooth isolation, a class V cavity was accessed from the buccal surface about 2 mm above the free gingival margin and parallel to the cementoenamel junction using a tungsten carbide pear-shaped bur, ISO #330 L. The access width was approximately 2−3 mm, and when the reddish pulp shadow was visible, a round carbide bur ISO # 1 (0.8 mm in diameter) was used to standardize the size of the pulp exposure to 0.8−1 mm. All cavity preparation procedures were performed at ultra-high speed with a copious water spray. To maximize cutting efficiency and preserve a sterile environment, each bur was used only once for each cavity . After rinsing the cavity with sterile saline and controlling the bleeding with a small cotton pellet under gentle pressure, the capping material was applied. In the experimental group, the crystalline SHMP was ground into fine powder. The powder was sterilized in a hot air oven before use. The powder with saline was mixed with saline in a 2 (powder):1 (liquid) proportion until a thick, workable mixture was obtained. The mix was applied using the MTA plug and condensed against the exposure site with a small, serrated amalgam condenser size¼ (HENRY SCHEIN®, USA) covered with a Teflon. Section title: Pulp capping procedures Educational score: 3.978598117828369 Domain: biomedical Document type: Study Language: en In the control group, MTA (white MTA Angelus, Londrina, PR, Brazil) was prepared according to the manufacturer's guidelines and placed over the exposed pulp by an MTA carrier (Angelus, Londrina, Brazil). A moistened cotton pellet was placed over the MTA to permit its setting under the final restorative material. Finally, the access cavities of all teeth were sealed with a glass ionomer restoration (RIVA self-cure, SDI Ltd. Victoria, Australia). Section title: Pulp capping procedures Educational score: 4.028012275695801 Domain: biomedical Document type: Study Language: en To assess the changes in root maturogenesis, 2D-digital periapical radiographs of the capped teeth were taken preoperatively and at the time of animal scarification. For standardization, all periapical images were taken using the paralleling technique (Vista Scan Mini Easy X-ray System, Bietigheim-Bissingen Germany). A PSP plate #2 (size of 3×4 cm) with a 100% active surface area was attached to a film holder that was mounted to a custom-made silicon-based index. Section title: Histological analysis and grading Educational score: 4.12048864364624 Domain: biomedical Document type: Study Language: en For specimen preparation and histological analysis, dogs were euthanized by thiopental overdose at the predetermined interval. Surgical dissection was used to split the mandibular and maxillary jaws into halves along their midline. The specimens were decalcified in 10% EDTA for 3 months after being fixed for 7 days in 10% neutral buffered formalin. The specimens were dehydrated using ascending grades of ethyl alcohol, cleared in xylene, impregnated in soft paraffin, and finally embedded in hard paraffin. Section title: Histological analysis and grading Educational score: 4.133785247802734 Domain: biomedical Document type: Study Language: en The capped teeth were extracted and washed thoroughly under running tap water for 3−4 h. To obtain serial sections of 5 μm thickness, extracted teeth were embedded in paraffin and cut buccolingually parallel to their vertical axis through the accessed cavities. Tissue sections were stained with haematoxylin and eosin (H & E) and Masson’s trichrome. The later was used to stain bone and collagen fibers and distiguish cells from the surrounding connective tissue . Representative photomicrographs were taken using a digital camera (LEICA, DFC290 HD system digital camera, Heerbrugg, Switzerland) connected to the light microscope using 4, 10, 20, and 40 objective lenses. Section title: Histological analysis and grading Educational score: 4.259106636047363 Domain: biomedical Document type: Study Language: en Based on the criteria of the modified scoring system of Stanley (Table 1 ), the calcified bridge and inflammatory response of the pulp were scored. The mean thickness scores of the calcified bridge, predentin, and odontoblastic layer were measured using ImageJ software (version 1.50i; National Institutes of Health, Bethesda, MD, USA). Table 1 Distribution of histological criteria according to the modified scoring system of Stanley Histological parameters and scoring SHMP MTA P * Dentin bridge (DB) formation Absent (score 0) 0(0) 0(0) < 0.05 < 25% of DB formed (score 1) 0(0) 0(0) 26–50% of DB formed (score 2) 0(0) 0(0) 51–75% of DB formed (score 3) 0(0) 6(33.3) 76–100% of DB formed (score 4) 18(100) 12(66.7) Location of calcified bridge At the interface of exposure pulp (score 1) 18(100) 18(100) 1.00 Not at the interface of exposure pulp (score 2) 0(0) 0(0) Both (score 3) 0(0) 0(0) Quality of dentin formation in the bridge Absence of dentinal tubules (score 0) 0(0) 0(0) < 0.05 Dentinal tubules have regular pattern (score 1) 14(77.8) 8(44.4) Dentinal tubules have irregular pattern (score 2) 4(22.2) 10(55.6) Dentin chips Absent (score 0) 9(50) 13(72.2) > 0.05 Present (score 1) 9(50) 5(22.8) Connective tissue in the bridge Absent (score 0) 14(77.8) 9(50) > 0.05 < 25% (score 1) 4(22.2) 9(50) 26–50% (score 2) 0(0) 0(0) 51–75% (score 3) 0(0) 0(0) 76–100% (score 4) 0(0) 0(0) Pulpal inflammation Absent (score 0) 18(100) 16(88.8) > 0.05 Mild (score 1) 0(0) 2(11.1) Moderate (score 2) 0(0) 0(0) Severe (score 3) 0(0) 0(0) Abscess formation (score 4) 0(0) 0(0) Tissue necrosis (score 5) 0(0) 0(0) Pulp tissue reaction to the material No inflammatory cell infiltration (score 0) 17(94.4) 14(77.8) > 0.05 Mild inflammatory cell infiltration (score 1) 1(5.6) 4(22.2) Moderate inflammatory cell infiltration (score 2) 0(0) 0(0) Severe inflammatory cell infiltration (score 3) 0(0) 0(0) SHMP Sodium hexametaphosphate, MTA Mineral trioxide aggregate * Monte Carlo exact test Section title: Radiographic measures and analysis Educational score: 4.071313858032227 Domain: biomedical Document type: Study Language: en Based on ImageJ software (version 1.50i; National Institutes of Health, Bethesda, MD, USA), the radiographic measurements included the following parameters : Root length (RL): a straight line from the CEJ to the apical foramen , apical foramen width (AFW) : a line extended between the mesial and distal root ends, and Root surface area (RSA): total root area minus the root canal space . Radiographic measures were estimated by an independent expert who was blinded to the used capping materials. Section title: Radiographic measures and analysis Educational score: 3.918210983276367 Domain: biomedical Document type: Other Language: en Fig. 2 Radiographic measurements reflect root maturation: ( a ) root length (RL) line extended from the CEJ to the apical foramen; ( b ) apical foramen width (AFW) line extended between the mesial and distal root terminals; ( c ) radiographic root area (RRA) calculated by subtracting the total root area from the root canal space Section title: Radiographic measures and analysis Educational score: 3.302367925643921 Domain: biomedical Document type: Study Language: en The histological specimens were examined independently by two experienced experts. The degree of agreement was checked using Cohen's Kappa (κ). Section title: Statistical analysis Educational score: 4.000174522399902 Domain: biomedical Document type: Study Language: en Statistical Program for Social Sciences for Windows (SPSS), version 22 (IBM© Corporation, NY, USA) was considered. The measurements of radiographic (RL, RSA, and AFW) and histological data (Thickness of the calcified bridge, predentin, and odontoblastic layer) were tested for normality and variance homogeneity using Kolmogorov–Smirnov and Shapiro–Wilk tests. For histological and radiographic normally distributed quantitative measures obtained, the paired-sample t-test was considered. While the qualitative data of Stanley's scoring system criteria were analysed using the Monte Carlo exact test. The alpha level of significance was set at 5-percent ( P ≤ 0.05) and a 95% confidence interval ( CI ). Section title: Findings of histological analysis Educational score: 4.1050567626953125 Domain: biomedical Document type: Study Language: en The inter-examiner agreement of the histological records was 0.89. Although, the average thickness of the calcific barrier in SHMP specimens (624.44 ± 12.44 µm) was higher than that found in the MTA specimens (587.79 ± 11.34 µm), the difference between the two groups was non-significant ( P > 0.05). On the other hand, the average thickness values of the predentin and odontoblastic layers were significantly higher in the SHMP specimens compared to the average thickness values in the MTA specimens . Section title: Findings of histological analysis Educational score: 3.0905826091766357 Domain: biomedical Document type: Study Language: en Fig. 3 Mean thichness of induced dentin bridges, predentin, and odontablastic layrs formed in resonse to sodium hexametaphosphate (SHMP) and mineral trioxide aggregate (MTA) Section title: Findings of histological analysis Educational score: 4.175158500671387 Domain: biomedical Document type: Study Language: en At the interface between the exposed pulps and both capping materials, the dentin bridge was fully calcified in 100% (18/18) of SHMP specimens, compared to 66.7% (12/18) of MTA specimens. Six MTA specimens (33.3%) showed partial formation of the dentin barrier. The difference between the two groups was statistically significant ( P < 0.05). The calcified barriers showed deeper H & E staining of in the SHMP group with more homogenous and regular patten of the dentinal tubules compared to the MTA group. Compared to MTA, the dentin bridge induced by SHMP showed a more palisading arrangement of the odontoblastic layer at the interface between dentin and pulp. There were numerous dentinal tubules within the developed hard tissue with homogenous well-arranged pattern similar to the dentin tubular structure (Table 1 ) and . The frequency of regularly arranged dentinal tubules in SHMP specimens [( n = 14 (77.8%)] was significantly higher compared to those shown in the MTA specimens [ n = 8 (44.4%)] ( P < 0.05). Section title: Findings of histological analysis Educational score: 4.237394332885742 Domain: biomedical Document type: Study Language: en Fig. 4 Photomicrograph of the dog's premolars capped with sodium hexametaphosphate (SHMP) ( a , b , and c ) and mineral trioxide aggregate (MTA) ( d , e , and f ), stained with H & E. Both materials show that the dentin (D) and pulp (P) are lined with normal odotoblastic layer (arrowheads). The dentin bridge (DB) at the interface between the material (M) and dental pulp (P) is highly organized in the SHMP group ( a ) and less organized in the MTA group ( d ). The magnified black boxed area shows that the two capping materials have loose connective tissue with many normal blood vessels (V) with few chronic inflammatory cells (curved arrow) in the SHMP group ( b ) and many chronic inflammatory cells (curved arrow) in the MTA group ( e ). The magnified red boxed area shows that the calcified bridge (B) induced by the two capping materials are formed from dentin chips. In the SHMP group, the dentin bridge is completely calcified with regularly arranged dentinal tubules and continuous odontoblastic cell layer (Black arrows) ( c ). In contrast, the dentin bridge in MTA group is incompletely calcified and the arrangement of dentinal tubules is less regularly arranged with no demarcating line between the dentin bridge and pulp (Black arrows) ( f ) (Scale bars: ( a ) and ( d ) 500 μm; ( b ), ( c ), ( e ), and ( f ) 100 100 μm) Section title: Findings of histological analysis Educational score: 4.094217300415039 Domain: biomedical Document type: Study Language: en Only two MTA specimens (11.1%) showed mild pulpal inflammation, while all SHMP specimens (100%) were free from pulpal inflammation ( P > 0.05). No inflammatory cell infiltration was observed in 94.4% and 77.8% of dental pulps in SHMP and MTA specimens, respectively ( P > 0.05). Section title: Findings of histological analysis Educational score: 3.973221778869629 Domain: biomedical Document type: Study Language: en The photomicrograph of the pulp tissue of specimens stained with Masson’s trichrome showed that SHMP specimens had fewer chronic inflammatory cells and normal blood vessels compared to many inflammatory cells and congested blood vessels in the MTA specimens . Section title: Findings of histological analysis Educational score: 3.963872194290161 Domain: biomedical Document type: Study Language: en Fig. 5 Photomicrograph of the dog's premolars capped with sodium hexametaphosphate (SHMP) ( a ) and mineral trioxide aggregate (MTA) ( b ), stained with Masson's trichrome. SHMP shows collagen bundles (black arrows) of the pulp (P) with few inflammatory cells (arrowheads) and normal blood vessels (V). MTA shows collagen bundles (black arrows) of the pulp (P) with many inflammatory cells (arrowheads) and congested blood vessels (V) (Scale bar 100 μm) Section title: Findings of radiographic analysis Educational score: 4.214248180389404 Domain: biomedical Document type: Study Language: en After three months, the mean differencs in mesial and distal root lengths of premolars capped with SHMP and MTA were 0.42 mm with 95% CI of 0.13; 0.72 ( P = 0.008) and 0.33 mm with 95% CI of 0.03; 0.64 ( P = 0.048), respectively. Regarding the other radiographic parameters (RSA and AFW), both capping materials acted in a comprable manner with no statistically significant difference ( P > 0.05) (Table 2 ) and . Table 2 Mean scores of different radiographic indicators of root maturation Radiographic parameters SHMP MTA 95% CI of mean difference P * Root length (RL/mm) Mesial RL at baseline 4.18 ± 0.19 4.16 ± 0.10 -0.08; 0.13 0.66 Mesial RL after 3 months 6.53 ± 0.44 6.11 ± 0.44 0.13; 0.72 0.008 Distal RL at baseline 3.73 ± 0.25 3.86 ± 0.27 -0.35; 0.09 0.24 Distal RL after 3 months 6.46 ± 0.47 6.13 ± 0.46 0.03; 0.64 0.048 Root surface area (RSA/mm 2 ) Mesial RSA at baseline 1.83 ± 0.27 2.00 ± 0.29 -0.37; 0.04 0.18 Mesial RSA after 3 months 3.39 ± 0.42 3.47 ± 0.38 -0.29; 0.05 0.17 Distal RSA at baseline 1.84 ± 0.25 1.96 ± 0.20 -0.34; 0.17 0.5 Distal RSA after 3 months 3.83 ± 0.27 3.92 ± 0.19 -0.23; 0.04 0.16 Apical foramen width (AFW/mm) Mesial AFW at baseline 1.74 ± 0.27 1.86 ± 0.21 -0.28; 0.05 0.16 Mesial AFW after 3 months 0.41 ± 0.13 0.47 ± 0.08 -0.14; 0.02 0.14 Distal AFW at baseline 1.71 ± 0.18 1.74 ± 0.11 -0.13; 0.08 0.58 Distal AFW after 3 months 0.47 ± 0.11 0.44 ± 0.10 -0.06; 0.09 0.65 SHMP Sodium hexametaphosphate, MTA Mineral trioxide aggregate * Paired sample t test Fig. 6 Periapical digital radiographs of dog's premolars show the change in mesial and distal root lengths (RL), apical foramen width (AFW), and root surface area (RSA) after capping with SHMP ( a and b ) and MTA ( c and d ). Radiographic parameter measures at baseline ( a ) and ( c ) and Radiographic parameter measures at 3 months ( b ) and ( d ) Section title: Discussion Educational score: 4.142545700073242 Domain: biomedical Document type: Study Language: en The results of histological analysis showed the superiority of the calcific bridge properties of SHMP over the MTA in terms of complete calcific barrier formation, the qualitative properties of dentin formed within the bridge, and the quantitative measures including the thickness of predentin and odontoblastic layers ( H 0 was rejected). While the findings of other histological criteria, including the thickness of the dentin bridge and pulpal inflammation or tissue necrosis, in the experimental and control groups were comparable ( H 0 was not rejected). Section title: Discussion Educational score: 4.003795623779297 Domain: biomedical Document type: Study Language: en The search for a novel capping material that provides a better pulp response is crucial before assessing the material's success in clinical situations. Additionally, to overcome the shortcomings of traditional MTA, alternative calcium silicate cements such as Biodentine, pre-mixed TotalFill BC RRM Putty, and pulp capping material (PCM) showed comparable high shear bond strength (SBS) values after immediate placement of the final restoration . Xavier et al. reported comparable SBS to Biodentine™ and NuSmile® NeoMTA with higher SBS values obtained after applying an extra layer of hydrophobic resin over the adhesive and placing the composite resin restoration 7 days after applying the calcium silicate cement (delayed restoration). However, cytotoxicity of freshly prepared (i.e., before setting) Biodentine and TheraCal has been encountered . Section title: Discussion Educational score: 4.030221462249756 Domain: biomedical Document type: Study Language: en One of the important aspects of pulp tissue response and the quality of dentin bridge is the preoperative pulp status . According to Ricucci et al. histological analysis of the coronal and radicular pulp tissues was normal for teeth that have been clinically diagnosed with reversible or irreversible pulpitis with necrotic foci next to the pulp horn. Mild to moderate grade of inflammation modulates the regenerative power of the pulp tissues, while severe and/or chronic inflammation has a determinant influence on the pulp . Therefore, the radical shift towards treating teeth with irreversible pulpitis via the use of bioactive capping materials has become a focus of attention . Another aspect of DPC success is the ability of the capping material to protect the pulp in a healthy state and trigger mineralized barrier formation with superior quantitative and qualitative characteristics . Section title: Discussion Educational score: 4.301044940948486 Domain: biomedical Document type: Study Language: en The dentin bridge induced by SHMP was better than that produced by MTA. The high ability of SHMP to elicit calcified bridge formation could be attributed to its ability to increase the activity of the ALP enzyme by upregulating the expression of non-specific ALP and endopolyphosphatase genes . The expression of other genes of bone matrix proteins, including osteonectin, OPN, and OCN, could be upregulated by Poly(P) . These trigger the differentiation and proliferation of odontoblasts of HDPCs and the subsequent deposition of calcified niches . Furthermore, the increased expression of ALP mediated by the long chain of SHMP prompts higher production of polymeric phosphate (PPi) and monomeric phosphate (Pi) in an optimal balance . This permits the production of Pi at optimal levels, which induces calcified foci formation . Section title: Discussion Educational score: 4.219839572906494 Domain: biomedical Document type: Study Language: en Another possible mechanism of action of Poly(P) is triggering the expression of the matrix metalloproteinase (MMP)−3 gene in response to the injury of dental pulp and the subsequent release of inflammatory mediators . The results of a study conducted in rats on odontoblast-like cells (iPS-OD) suggested that upregulated MMP-3 genes elicited a hierarchy of activation of odontoblastic markers, including dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1). As a result of the serially upregulated cascade of odontoblast markers mediated by MMP-3, the proliferation and osteogenic differentiation of odontoblast-like cells have increased . Section title: Discussion Educational score: 4.103791236877441 Domain: biomedical Document type: Study Language: en An integral part of pulp regeneration is the potential to organize a network of vascular capillaries (i.e., angiogenesis). SHMP, as a member of Poly(P), has the potential to elicit the migration and differentiation of HDPCs into endothelial cells through the evident elevation of the angiogenic markers, indicating an up-regulatory effect of Poly(P) on the angiogenic genes . Section title: Discussion Educational score: 4.1958513259887695 Domain: biomedical Document type: Study Language: en The MTA-induced calcified barrier was evident in all specimens with a variable degree of mineralization, indicating that the mineralization process of the matrix was heterogeneous. This agreed with the findings of a previous histological animal model study . Interestingly, the current study findings showed that the degree of mineralization of dentin bridges formed in response to SHMP capping material was significantly superior to those organized by MTA. This observation might denote the faster rate of mineralization reaction of SHMP compared to MTA. The rate of calcification could be considered a determinant criterion for pulp capping materials . This observation was confirmed by the presence of connective tissue in half of the MTA specimens. This was in line with the findings of a prior histological analysis that connective tissue was detected in 40 percent of DPC samples. The results of the current study revealed that the newly formed odontoblast-like cell layer has a well-organized tubular system that could reflect the adequate surface adherence properties of the capping material. This prompts the better organization and differentiation of odontoblast-like cells . Section title: Discussion Educational score: 4.048352241516113 Domain: biomedical Document type: Study Language: en Depending on the formation of the dentin bridge exclusively as an indicator of capping material success is not enough to justify a healthy pulp status . There have been no previous reports regarding the pulpal inflammation response of SHMP. According to the findings of the present study, all specimens were free from inflammatory pulpal responses. The absence of pulp tissue inflammation and the highly qualitative and quantitative properties of the induced calcified tissue bridge refer to the superior bioinductive and biocompatible nature of the SHMP capping agent. Section title: Discussion Educational score: 4.280483245849609 Domain: biomedical Document type: Study Language: en Regarding the MTA-induced calcified bridge, the aqueous medium provides a suitable environment for calcium hydroxide formation . At the interface between the material and pulp tissues, calcite-like structures are precipitated . The developed crystals could attract the fibronectin required for cell adhesion and differentiation . The initial caustic pH level of MTA (pH of 12.5) at three hours following mixing . The high pH continues up to eight weeks following material hardening . The high alkaline pH provides an optimum microenvironment for hard tissue barrier induction through the regulated release of cytokines and controlled inflammatory processes . Section title: Discussion Educational score: 4.17014217376709 Domain: biomedical Document type: Study Language: en Radiographic analysis of the teeth capped with both capping agents permits root maturogenesis in terms of the increase in RL and RSA and the closure of the apexes of dogs' premolars. However, the mesial and distal roots of teeth capped with SHMP revealed a significant increase in their RLs compared to those treated with MTA. Other radiographic parameters showed comparable results between the two materials. The relative radiographic superiority of SHMP over MTA emphasized the advantageous findings of histological analysis. The relative advantage in radiography could be attributed to the better healing conditions in terms of better qualitative and quantitative calcified bridge formation and less induced inflammation obtained by SHMP at the site of pulp injury. This favorable environment may encourage a faster healing rate compared to the MTA group. However, this point should be examined deeply in further investigations, as the histological and radiographic examinations are carried out over more than one period. Section title: Discussion Educational score: 3.853985071182251 Domain: biomedical Document type: Study Language: en In the current study, a 3-month interval was adopted before considering histological and radiographic examination. This period was considered to ensure significant maturogenesis of the dog's roots. Moreover, this period provided a better chance for dentenogenesis to take place and permitted the maturation of the calcified dentin bridge. A similar interval was considered in a previous study , in which animals were sacrificed and specimens were assessed. Section title: Discussion Educational score: 3.722612142562866 Domain: biomedical Document type: Study Language: en The main advantages of SHMP were the cost compared to the MTA. The 500 gm of SHMP costs 78.35 US$. Approximately each tooth was capped with 250 mg powder of SHMP or MTA. Thus, each tooth capped with SHMP costed about 3.92 cents, while the tooth capped with MTA costed about approximately 4.12 US$. The other merits of the use of SHMP include the ability to apply the final adhesive restoration with no obvious crown discoloration compared to crowns of teeth treated with MTA. However, further investigations are required to elucidate the long-term effect of SHMP on the color change and mechanical properties. Section title: Discussion Educational score: 4.172155857086182 Domain: biomedical Document type: Study Language: en The main limitations of the present study are that it was performed in an ideal environment with sound dogs' teeth, healthy pulps with no previous inflammation, and standardized exposure sizes and sites. Therefore, it cannot guarantee that the response of the pulp tissues with preoperative inflammation will be similar . The reaction of the pulp is totally different according to the type of exposure (traumatic injury, mechanical stimulus, or caries) . Initially after the exposure, neuropeptides are released because of adjacent neural damage that is associated with an increase in vascular permeability . The predominant inflammatory cells in the initial phase are lymphocytes, plasma cells, and macrophages associated with polymorphonuclear leukocytes in the acute phase, then the condition becomes chronic . The chemotaxis of large numbers of neutrophils at the exposure site. This induces NETosis as a defensive mechanism which occurs because of the death of neutrophils. In NETosis, neutrophil extracellular traps destroy the invasive bacteria . Mild to moderate inflammation is associated with reactive or reparative dentinogenesis, while severe inflammation may destroy the odontoblasts . Section title: Discussion Educational score: 4.043935775756836 Domain: biomedical Document type: Study Language: en As previously mentioned, an early histological assessment might be required to provide a comprehensive perception regarding the inflammatory changes and the rate of healing of the SHMP capping material. Further studies are required to test the antimicrobial and sealing characteristics of SHMP and its sealing ability. Additionally, analysis of teeth with pulp exposure because of carious lesions is needed. Finally, assessment of the root maturogenesis depended on two-dimensional images. Therefore, future studies using 3D radiographs will be more beneficial. Additionally, further prospective clinical trials are required to confirm the effectiveness of SHMP and generalize the results of the present study. Section title: Conclusions Educational score: 4.107441425323486 Domain: biomedical Document type: Study Language: en Within the limitations of the present study, it can be concluded that: There was no difference in some respects between SHMP and MTA. The histological evaluation showed that SHMP provided better bioinductive and biocompatible properties compared to MTA. Radiographically, both materials showed comparable root maturogenesis outcomes except for the increase in RL, which was significantly longer after DPC with SHMP. SHMP might be a suitable DPC alternative material in the treatment of immature permanent teeth. Further prospective randomized clinical trials are necessary to prove the findings of the current study. | Other | biomedical | en | 0.999998 |
PMC11697944 | Section title: Background Educational score: 4.2472052574157715 Domain: biomedical Document type: Study Language: en Mutualistic fungi that live in symbiosis with plants play pivotal roles in the recycling of carbon, nitrogen, phosphorus, and other nutrients in the boreal forest ecosystem, many of which belong to ectomycorrhiza group. Ectomycorrhizal (ECM) fungi wrap around host lateral roots to form fungal mantle and form hartig net between epidermal and cortical root cells . Ectomycorrhizal fungi (ECF) that form symbiosis with trees has the capacity to influence growth limiting nutrient resources in forest ecosystem . The authors further noted that EMF composition was associated to a three-fold difference in tree growth and that fast tree growth was linked with EMF that harbored high inorganic nitrogen acquisition genes. ECM fungi have received in recent years heightened attention as key mediators which function within common mycorrhizal networks [ 3 – 6 ], which are associated with water and nutrient mobilization , plant growth in symbiotic performance [ 8 – 10 ], tree transcriptome in ectomycorrhizal symbiosis [ 7 , 11 – 15 ]. Rudawski et al. noted the dominance of several ECM ( Suillus luteus, Rhizopogon roseolus, Thelephora terrestris, Hebeloma crustuliniforme ) in Scots pine seedlings in forest nursery. Policelli et al. reported that ECM helps temperate and boreal forest trees to tolerate harsh environmental conditions such as restoration of sites degraded due to clearcut logging and wildfire, affected by soil erosion and contaminated with heavy metals as well as restoring sites invaded by non-native plant species. Section title: Background Educational score: 4.23037576675415 Domain: biomedical Document type: Study Language: en Unlike the main saprotrophic decomposers which dominate in freshly produced organic matter, ECM fungi dominate in deeper soil layers . They potentially act as decomposers, mobilizing N from the soil organic matter pool and making it available to their host plants . ECM fungi have nutrient transporters in their genome for nutrient mobilization . ECM fungi have a limited capacity to decompose plant litter as revealed by the analysis of genome sequences , including Laccaria bicolor , Tuber melanosporum and mycorrhizal Amanita species . Genome analysis on those ECM fungi indicated the loss of some genes encoding plant cell wall degrading enzymes such as glycoside hydrolases and peroxidases compared to their saprotrophic ancestors . The reductions and losses in specific protein families could be an indication of adaptation of ectomycorrhizal biotrophy in plant tissues . Section title: Background Educational score: 4.191361427307129 Domain: biomedical Document type: Study Language: en Host plants are the principal sources of metabolic carbon for ECM fungi, which in turn also benefit from ectomycorrhizal colonization. ECM fungi promote plant growth by enhancing water and nutrient uptake especially nitrogen and phosphorus . Root biomass and length of Populus nigra increased under ECM fungus inoculation . Several ECM fungi could change tree root architecture (including overall root growth, primary and lateral root length, lateral root number), in which plant hormones signaling and auxin pathways could be involved . ECM can also improve plant performance by inducing local and systemic defense responses which may be controlled by signaling networks involved in plant hormones salicylic acid (SA), jasmonic acid (JA), and ethylene, to confer broad-spectrum resistance during subsequent plant pathogen or herbivore attack . Section title: Background Educational score: 4.165676116943359 Domain: biomedical Document type: Study Language: en Suillus luteus , which is also called slipper Jack, is a common ECM fungus with pines, such as Pinus sylvestris , P. elliottii . S. luteus had the ability to help P. massoniana absorb phosphorus under nutrient deficiency . S. luteus promoted the growth of P. massoniana seedlings, producing phytohormones, especially SA and indole-3-carboxylic acid (ICA), methyl indole-3-acetate (ME-IAA), and indole-3-acetic acid (IAA) in mycelium . Stone pine without S. luteus symbionts could be more easily susceptible to H. annosum than plants with ectomycorrhizal symbiosis . Mycorrhizal inoculation of Suillus spp. increased chlorophyll a and b, carotenoids, and soluble protein in Scots pine young seedlings, and increased the activities of plant antioxidant enzymes CAT and POD, and plant beta-1,3-glucanase . Section title: Background Educational score: 4.287901401519775 Domain: biomedical Document type: Study Language: en Scots pine, dominating in boreal forest, is highly susceptible to infection by necrotrophic basidiomycete Heterobasidion annosum sensu stricto (Fr.) Bref. . Aerial basidiospores of the fungal pathogen fall on freshly cut stumps and form invasive hyphae, followed by spreading to nearby trees via root contact . The fungal pathogen grows necrotrophically to get nutrients from the living tree tissues and then turns to saprotrophic growth in dead wood cells , which may lead to reduced volume growth and tree mortality. Tree defense responses in conifer- Heterobasidion pathosystem demonstrated that the phenylpropanoid pathway, lignin biosynthesis and polymerization, flavonoids biosynthesis, terpenoid and stilbene pathways, and pathogenesis-related (PR) proteins are the principal responses at the gene level [ 39 – 46 ]. Jasmonic acid and ethylene signaling pathway plays a central role in tree defense responses to Heterobasidion infection, without antagonism of salicylate-mediated signaling pathway . Section title: Background Educational score: 3.9921517372131348 Domain: biomedical Document type: Study Language: en Plant defense responses to Heterobasidion infection and beneficial microbe inoculation such as endophyte have been recorded . However, there are limited studies on plant response to ECM fungi in the presence of pathogenic fungi. The hypothesis is that pre-inoculation of plants with ECM fungi before fungal pathogen challenge would improve plant performance and help plant defense against pathogen infection. We investigated the similarities and difference in host responses between pathogenic and mutualistic fungal interaction, host responses towards pathogenic attack that were maintained under co-inoculation, and host responses towards pathogenic attack that are dampened by the presence of ECM fungus. Section title: Mutualistic beneficial fungus and plant materials Educational score: 4.03819465637207 Domain: biomedical Document type: Study Language: en Suillus luteus was obtained from the University of Helsinki Fungal Biotechnology Culture Collection (HAMBI/FBCC). Heterokaryotic Heterobasidion annosum 02034 was obtained from the culture collection of Kari Korhonen. Scots pine seeds were kindly provided by Natural Resources Institute of Finland (Luke). S. luteus was stocked on Modified Melin-Norkrans medium . H. annosum was maintained on malt extract agar . Scots pine seeds were surface sterilized with 30% H 2 O 2 for 15 min, rinsed several times with sterile water and stratified for 3–4 days in the dark at 4 ◦C. Rows of seeds were laid on 12*12 cm sterile square Petri dishes with 1% water agar and covered with moist, sterile filter paper. The Petri dishes containing seeds were sealed with parafilm, placed in a growth chamber for germination under a photoperiod of 16 h at 20 ◦C for 2 weeks. Section title: Dual cultures on artificial agar media Educational score: 4.043188095092773 Domain: biomedical Document type: Study Language: en Dual cultures of H. annosum and S. luteus were set up on MMN media to investigate the impact of the ECM fungus on the pathogenic fungus growth. S. luteus agar plug (5-mm diameter) was put on the agar media 13 days before adding H. annosum agar plug, as the former grows slower than the latter. The distance between the two plugs was 6 cm on Petri dish. Self-pairing refers to two separate agar plugs of the same fungus on the culture plate and served as the control. The fungal cultures grew at 20°C in the dark. Section title: Seedling inoculation and sampling Educational score: 3.998692274093628 Domain: biomedical Document type: Study Language: en S. luteus was cultured on a 9-cm circular Petri dish with MMN agar media. One month later, agar plugs on the edge of the fungal culture with active mycelia were moved to a 12-cm square Petri dish with MMN agar media and cellophane membrane. S. luteus was growing on membrane agar plates for 17 days, and then the membrane with the fungal mycelia was moved into a new 12-cm square Petri dish containing MMN agar media. Section title: Seedling inoculation and sampling Educational score: 4.129322528839111 Domain: biomedical Document type: Study Language: en Two-week-old Scots pine seedlings were placed on the top of the fungal mycelia in the square Petri dish with MMN. Fungal mycelia and plant seedlings were grown together on Petri dish for one month to ensure successful inoculation and establishment of the ECM fungus on the plant. One month later, ECM fungus-inoculated seedlings were transferred into soil. The soil was peat-based substrate provided by Kekkilä Professional (Vantaa, Finland). Dry soil was mixed with water, and the moist soil was autoclaved at 121°C for one hour (two times) with an interval of 48 h. The autoclaved soil was put into the 12 cm-sterile square plates. Three or four infected seedlings were transferred into each soil plate. Seedlings were grown in the soil for one month before adding H. annosum . H. annosum used for the inoculation was pre-incubated in the malt agar media for 3 weeks. Ten agar plugs (0.5 cm in diameter) with active fungal mycelia were introduced into the soil next to the plant roots. The seedlings were watered every two weeks. In total, there were four groups of seedlings, including control seedlings without any inoculum (Ctr), Mutualistic fungus-inoculated seedlings (Sl), pathogen-infected seedlings (Ha), and co-inoculated seedlings with both the ECM fungus and the pathogen (SlHa, or co-inoculation). There were at least three Petri dishes for each group which served as biological replicates, with 3–4 seedlings in each dish. Seedlings were grown with H. annosum together for one month before sampling. At the time of sampling, Scots pine seedlings were three and half months old. By then, S. luteus had grown with the plants for three months, while H. annosum was with the plants for one month. The number of the lateral roots, the length of primary roots of the seedlings were counted and measured at termination of the experiment. Section title: RNA extraction, library construction, and differential gene expression analysis Educational score: 4.124307155609131 Domain: biomedical Document type: Study Language: en Seedling roots were collected for RNA isolation as previously described . Transcriptome sequencing (paired-end, 101bp) was performed at CeGat (Germany). Sequencing libraries were generated by using TruSeq Stranded mRNA (Illumina). The library preparations were sequenced on Illumina NovaSeq 6000. Raw reads were preprocessed by CeGat. Demultiplexing of the sequencing reads was performed with Illumina bcl2fastq (2.20). Adapters were trimmed with Skewer (version 0.2.2). Trimmed raw reads were aligned to the annotated contigs of Pinus taeda v2.01 using the Illumina DRAGEN platform (software version 3.10.4). As Pinus sylvestris has presently no well annotated genome, thus we used P. taeda as the mapping genome. The P. taeda genome was also used for the analysis of P. sylvestris transcriptomic data partly because the P. taeda and P. sylvestris sequences showed high level of sequence similarity . Section title: RNA extraction, library construction, and differential gene expression analysis Educational score: 4.100160121917725 Domain: biomedical Document type: Study Language: en The raw reads count was used to identify differentially expressed genes in Ha, Sl, and SlHa compared to Ctr using edgeR package in R v.4.3.3. Genes with at least 1 count per million in at least 3 libraries were utilized for further analysis. Normalized counts obtained by DESeq2's median ratios were transformed using rlog transformation to improve the distance or clustering for principal component analysis (PCA) and hierarchical clustering visualization. The cutoff values for defining differentially expressed genes (DEGs) were false discovery rate adjusted P -value (Benjamini and Hochberg’s approach) = 0.05 and |log2(fold change) |= 1. Section title: Functional annotation Educational score: 4.082859516143799 Domain: biomedical Document type: Study Language: en Coding sequences (CDS) of P. taeda were extracted from PlantGenIE. The CDS sequences of genes with at least 1 count per million in at least 3 libraries were blasted to Scots pine de novo transcriptome assembly fasta sequences constructed with Trinity . Since all Trinity assembly transcripts had been also annotated , we were able to gain the annotation information with nucleotide blast. The best hits were selected by bit scores. Gene ontology (GO) enrichment of DEGs was analyzed by clusterProfiler . R packages such as ggplots, enrichplot, pheatmap were utilized for dotplots, GO maps, and heatmaps. Section title: Results Educational score: 2.989194631576538 Domain: biomedical Document type: Study Language: en The interaction between the ECM fungus and the pathogen in dual agar culture was found to be neither antagonistic nor antibiosis (Additional file 1). Section title: Results Educational score: 4.143357276916504 Domain: biomedical Document type: Study Language: en The two fungi were then inoculated either alone or together on roots of Scots pine seedlings. To ensure successful colonization of the roots, S. luteus was grown with plant seedlings for a month on artificial media before being transferred to the soil. However, mycorrhization marked by mantle formation or hartig net was not observed. A total of 88 seedlings were harvested (Additional file 2), including 22 seedlings from control (Ctr), 14 seedlings from H. annosum infection (Ha), 29 seedlings from S. luteus inoculation (Sl), and 23 seedlings from co-inoculation (SlHa) and used for phenotyping. While 38 seedlings were used for RNA sequencing as shown in Fig. 2 . Principal component analysis based on the primary root length and lateral root number showed that growth of Ha and Ctr could be different from Sl and SlHa . The median values of primary root length in Sl and SlHa were 13.1 cm and 17.2 cm, significantly higher than the values in Ctr and Ha (8.4 cm, 10 cm). The median values of the number of lateral roots in Sl and SlHa were 15 and 23, while the values in Ctr and Ha were 9 and 7.5, respectively . We found that seedlings in both Ha and Ctr grew poorly, suggesting pathogenic or other forms of stress in the two conditions. However, the plant root growth was improved significantly with the presence of S. luteus . Therefore, we reasoned that S. luteus as a beneficial fungus promoted plant root growth. Consequently, the term mutualistic or beneficial was utilized to qualify the interaction in this study. Fig. 1 The growth of Scots pine seedlings with fungal infection. A Principal component analysis based on the primary root length and lateral root number. B Box plot about primary root length of seedlings. C Box plot about lateral root number. Ctr: non-inoculated seedlings control; Ha: Heterobasidion annosum -inoculated seedlings; Sl: Suillus luteus -inoculated seedlings; SlHa: H. annosum -infected seedlings in the presence of S. luteus (co-inoculated plants). Asterisks indicate whether significant difference exists in the primary root length or lateral root number of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.001: ***; p < 0.01: **; p < 0.05: *) Fig. 2 Images of Scots pines seedlings used for RNA sequencing. C: non-inoculated seedlings control; Ha: H. annosum -inoculated seedlings; Sl: Suillus luteus -inoculated seedlings; SlHa: H. annosum -infected seedlings in the presence of S. luteus (co-inoculated plants). Numbers refer to the Petri dish ID in Additional file 2 Section title: The RNAseq and transcriptome analysis Educational score: 4.2235307693481445 Domain: biomedical Document type: Study Language: en About 73%—86% of sequenced fragments were mapped to Pinus taeda genome, and 35%-40% of the mapping fragments were used for expression quantification (Table 1 ). The results seem to show that the presence of S. luteus appeared to have a balancing buffering effect on the plant stress response in the presence of H. annosum . This is partly evident as principal component analysis (PCA) and hierarchical clustering revealed that the SlHa bio-replicates were much closer to Ctr and Sl, and far away from Ha replicates under 47% variance . Data for PCA and hierarchical clustering visualization was based on normalized counts as seen in Additional file 3. Table 1 RNA sequencing and mapping results to Pinus taeda genome. Scots pine seedlings without fungal inoculation (Ctr), and seedlings inoculated with H. annosum (Ha), S. luteus (Sl), and both (SlHa). Each treatment condition has three biological replicates Sample ID Number of fragments (in million) Number of bases (in Gb) Number of mapped fragments (in million) Proportion of sequenced fragments (in %) Number of fragments used for expression quantification (in million) Proportion of fragments used for expression quantification (in %) Ctr-4 34.944 7.042 29.7335 85.09 10.773 36.58 Ctr-6 34.812 7.025 29.9565 86.05 10.547 35.69 Ctr-7 40.255 8.119 34.1495 84.83 12.233 36.31 Ha-1 43.887 8.853 34.2225 77.98 12.494 36.97 Ha-3 28.883 5.81 21.246 73.56 8.024 38.11 Ha-4 34.919 7.034 26.603 76.18 10.08 38.25 Sl-4 51.438 10.275 42.967 83.53 17.068 40.19 Sl-7 33.48 6.741 28.2565 84.4 10.338 36.94 Sl-10 32.366 6.518 27.1815 83.98 9.731 36.15 SlHa-2 27.209 5.476 22.631 83.18 8.253 36.77 SlHa-3 35.059 7.076 29.53 84.23 10.173 34.83 SlHa-4 54.151 10.826 44.958 83.02 17.437 39.32 Fig. 3 RNAseq profiling of Scots pine in Ctr, Ha, Sl and SlHa. A PCA plot of rlog-transformed normalized counts obtained by DESeq2's median of ratios. B Heatmap of hierarchical clustering of normalized counts Section title: The RNAseq and transcriptome analysis Educational score: 4.194544792175293 Domain: biomedical Document type: Study Language: en The expression of genes obtained by DESeq2's was shown in the heatmap (Additional file 4) using the Log2(1 + normalized CPM). As seen in the heatmap, Ha had a unique expression profile, largely different from Ctr, Sl, and SlHa . This validated the balancing buffer role and counteracting effect of S. luteus . We extracted the significant differentially expressed genes (DEGs) in Ha, Sl, SlHa comparing against Ctr with edgeR. About 440 DEGs were found in Ha, 403 in Sl, and 420 in SlHa . 31 common DEGs were found in Ha, Sl, and SlHa. Additionally, Sl shared 157 DEGs with SlHa, and most genes were downregulated . However, Ha shared only 32 DEGs with Sl and 47 DEGs with SlHa . The original data about normalized CPM, log2foldchange, and FDR value are shown in Additional file 5. Fig. 4 A 440, 403, 420 DEGs were found in Ha, Sl, SlHa relative to Ctr. 330, 183 and 185 DEGs were specific in Ha, Sl, SlHa respectively. 31 DEGs are common genes which were shared in Ha, Sl, SlHa. 32, 47, 157 DEGs were overlapped between Ha and Sl, Ha and SlHa, Sl and SlHa. B Hierarchical clustering of DEGs using log2foldchang based on Venn diagram. Specific genes, overlap genes between two conditions, and common genes shared in three conditions were illustrated in heatmap and each group can be divided into downregulated genes and upregulated genes. For example, 330 DEGs specifically in Ha in Venn diagram were grouped in upregulated genes and downregulated genes in the heatmap. Ctr: non-inoculated seedlings control. Ha: pathogen-infected seedlings. Sl: Suillus luteus -infected seedlings. SlHa: co-inoculated seedlings with both S. luteus and H.annosum . ‘ + ’ refers to upregulated, while -’ refers to downregulation. Ha.Sl.SlHa: + + + refers to DEGs that were upregulated in all treatments compared to Ctr. Ha.Sl: + + refers to DEGs that were upregulated both in Ha and in Sl. Ha.SlHa: +-refers to DEGs that were upregulated in Ha but downregulated in SlHa. Scale bar refers to log2foldchang. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *) Section title: The RNAseq and transcriptome analysis Educational score: 4.108186721801758 Domain: biomedical Document type: Study Language: en The best hits with annotation information were shown in Additional file 6. The top 20 significant GO terms of molecular function were selected in Ha, Sl, and SlHa . The GO terms related to pinosylvin synthase activity and peroxidase activity were enriched in Ha and Sl, but not in SlHa. Many GO terms were enriched only in Ha (linoleate 9S-lipoxygenase activity, glucan endo − 1,3 − beta − D − glucosidase activity, endochitinase activity, chitin binding) or only in Sl (hydroquinone: oxygen oxidoreductase activity, manganese ion binding, magnesium ion binding, oxidoreductase activity, abscisic acid binding, terpene synthase activity, copper ion binding). The GO terms shared in the three different samples were flavin adenine dinucleotide binding, mandelonitrile lyase activity, oxidoreductase activity. Fig. 5 Go enrichment for DEGs–Top 20 significant GO terms of molecular function were selected in Ha, Sl, and SlHa. GeneRatio is calculated as "input gene number"/ "backgound gene number" Section title: Similarities and differences in plant response genes towards pathogenic attack and beneficial interaction Educational score: 4.149936676025391 Domain: biomedical Document type: Study Language: en Similar gene expression pattern was observed between Ha and Sl which was marked by the upregulation of genes related to leucine-rich repeat domain receptor-like kinases (LRR-RLKs), SWEET sugar transporters, xyloglucan endotransglucosylase/hydrolase (XTH), E3 ubiquitin ligases, UDP-glycosyltransferase (UGT), and downregulation of cinnamoyl-CoA reductase (CCR) and α-xylosidases . The expression pattern of these genes was still maintained in the co-inoculation (SlHa) . However, several DEGs encoding for L-type lectin-domain containing receptor kinase (LecRLKs), CML, UDP-glycosyltransferase (UGT), cytochrome P450, that were found in Ha and Sl, were not significantly expressed in co-inoculation (SlHa) . Fig. 6 Heatmap of DEGs using log2foldchange which commonly up- or down-regulated in three treatments, and DEGs which were up- or down-regulated both in Ha and Sl, and DEGs which were up- or down-regulated in both Ha and SlHa. Scale bar refers to log2foldchang. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *) Section title: Similarities and differences in plant response genes towards pathogenic attack and beneficial interaction Educational score: 4.186647415161133 Domain: biomedical Document type: Study Language: en Genes which were upregulated in Ha but downregulated in Sl included eight predicted peroxidases, nine pinosylvin synthases belonging to chalcone/stilbene synthases, three glucosyl hydrolases related to PR proteins, two laccases, ABC transporter, protein HOTHEAD, ACC oxidase . H. annosum infection had unique expression pattern on genes encoding pathogenesis-related (PR) proteins (peroxidases, chitinases, β -1,3-glucanases, thaumatin), phenylpropanoid pathway/lignin biosynthesis (PAL, 4CL, COMT, CCoAOMT, peroxidases, laccases, cytochrome P450s), flavonoid biosynthesis, chalcone/stilbene biosynthesis, ethylene signaling pathway, JA signaling pathway, cell remodeling and growth, transporters, fungal recognition (Additional file 7, Additional file 8). Fig. 7 Heatmap of DEGs using log2foldchange which were upregulated in Ha but downregulated in other conditions. Scale bar refers to log2foldchang. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *) Section title: Similarities and differences in plant response genes towards pathogenic attack and beneficial interaction Educational score: 4.144822120666504 Domain: biomedical Document type: Study Language: en Whereas Sl induced a smaller unique set of genes but had more downregulated genes than Ha . S. luteus specifically induced plant genes which are mostly implicated in root growth promotion. The Sl-specific upregulated genes were associated with nutrient uptake (transporters), terpene biosynthesis and lignin biosynthesis (terpene synthases and cytochrome P450s), fungal recognition (cysteine-rich receptor-like protein kinases), hormone signaling (LOX, α-dioxygenase, MAPK) . However, the Sl-specific downregulated genes were mostly encoding genes involved in plant defense responses, especially PR proteins, and other defense-related genes including laccases, chalcone/stilbene synthases, terpene synthases, cytochrome P450s, receptor-like protein kinases (RLKs) related to fungal recognition (Additional file 9). By contrast these defense related genes were not significantly expressed in SlHa co-inoculation. Fig. 8 Heatmap of DEGs which were specifically upregulated in Sl. Red indicates high level of upregulation, while blue indicates high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *) Section title: DEGs in either pathogenic attack or beneficial interaction were also maintained under co-inoculation Educational score: 4.156317234039307 Domain: biomedical Document type: Study Language: en A set of DEGs found in Ha were also found to be maintained in SlHa . Many of the upregulated genes involved in sugar transporters, annexin Gh1 related to calcium-permeable transporters, RMR function in transporting storage proteins to protein storage vacuole, ethylene-responsive transcription factors and basic endochitinase CHB4. The downregulated transcripts included genes related to glycine-rich domain-containing protein, expansin-like A, disease-resistance locus receptor-like protein kinase, GH36, flavin monoamine oxidase, and Zinc-containing alcohol dehydrogenase . On the other hand, Sl shared many DEGs with SlHa (Additional file 10, Additional file 11), with major downregulated genes such as receptor-like protein kinases, glycosyl hydrolases, peroxidases, laccase, ABC transporters, calcium-binding proteins (Additional file 11). Section title: Unique DEGs during SlHa co-inoculation Educational score: 4.31268835067749 Domain: biomedical Document type: Study Language: en Plants pre-inoculated with S. luteus and subsequently challenged with H. annosum were not negatively affected in terms of root growth like the plants inoculated with S. luteus alone. Ha invested efforts in the induction of PR proteins and stilbene synthases under pathogen attack, while SlHa gene machinery was reprogrammed towards cell wall modification (e.g. XTHs, pectinesterases, chitinase-like protein, β-mannanase, GTs, UGTs, EXORDIUM-like protein), water and nutrient uptake proteins (aquaporins, aluminum-activated malate transporter 3, bidirectional sugar transporter SWEET3b, and aluminum-activated malate transporter), fungal recognition (LRR-RLKs, LecRLKs) (Additional file 12, Additional file 13). SlHa also induced a set of genes involved in phenylpropanoid/lignin biosynthesis/flavonoid biosynthesis (CcoAMT, ANR, two bifunctional pinoresinol-lariciresinol reductases, LACs, GGPP synthases, cytosolic sulfotransferase), auxin homoeostasis (WAT1-relaterd proteins, auxin-responsive protein SAUR32), and genes involved in hormone signaling (calcium uniporter protein, E3 ubiquitin ligases with U-box domain, abscisic acid receptor, LOX, Salicylic acid 3-hydroxylase) (Additional file 12). S3H can hydrolyze salicylic acid (SA) to 2,3-DHBA, a deactivated form of SA to prevent over accumulation of SA . SlHa had two S3Hs upregulated but four downregulated, while Ha induced four S3Hs. This could indicate that different hormone signaling pathways were utilized by plants in response to SIHa inoculation. Section title: Unique DEGs during SlHa co-inoculation Educational score: 4.049257755279541 Domain: biomedical Document type: Study Language: en DEGs specifically upregulated in SlHa were also involved in fungal recognition such as G-type LecRLKs and LRR-RLKs, disease resistance NB-LRR. By contrast some genes related to fungal recognition were found to be downregulated, including two cysteine-rich receptor-like protein kinases, three G-type LecRLKs, and three LRR-RLKs (Additional file 13). Section title: Discussion Educational score: 4.093673229217529 Domain: biomedical Document type: Study Language: en In this study, although no mantle or Hartig net was formed as a sign of mycorrhization during the short period of the experiment, the beneficial impact of S. luteus in promoting plant primary root growth was still evident. Other authors previously reported that S. luteus mycorrhiza enhanced plant growth by taking up a greater quantity of phosphorus than non-mycorrhizal roots of young seedlings of P. radiata . To ensure successful colonization of the roots, ECM fungus S. luteus mycelia and plant seedlings were left to grow together for a month on artificial media before transfer into the soil. No barrage or demarcation zone was observed in the dual culture of S. luteus and H. annosum , which suggested that S. luteus probably had no antagonism or antibiosis effect on H. annosum growth. Sillo et al. noted that Heterobasidion spp. isolates always completely overgrew S. luteus . Section title: Discussion Educational score: 4.2782721519470215 Domain: biomedical Document type: Study Language: en The interactions between the Scots pine seedling roots with either the pathogen or the beneficial fungus were most likely regulated by pathogen or microbe associated molecular patterns (PAMP/MAMP). Most often plants deploy plasma membrane-localized pattern recognition receptors (PRRs) and nucleotide-binding (NB)-LRR proteins to recognize MAMPs/PAMPs, or effectors, eliciting MAMP/PAMP-triggered immunity (MTI/PTI), effector-triggered immunity (ETI) . Plants could differentiate symbiotic microbes from pathogens by receptor competition and inhibit MTI for symbionts . LRR-RLKs and LecRLKs probably served as PRRs [ 58 – 60 ]. In our study, the expression of gene encoding LRR-RLKs and L-type LecRLKs in both Ha and Sl may indicate the perception of conserved MAMPs in H. annosum and S. luteus . Chitin and β-glucan are typical fungal MAMPs . SWEET sugar transporters were found to be expressed in Ha and Sl in this study. SWEETs facilitate sugar flux across the cell membrane , and some SWEETs can bind bacterial effectors . The sugar efflux function of SWEET transporters probably help pathogens and symbionts for their nutrition . PtaSWEET1c, which was identified in Populus tremula × alba – Laccaria bicolor symbiosis, was localized in the host plasma membrane surrounding the Hartig net to unload glucose and sucrose to meet the nutritional demands of colonizing hyphae . Section title: Discussion Educational score: 4.525521278381348 Domain: biomedical Document type: Study Language: en Most DEGs in Ha were upregulated while most DEGs in Sl were downregulated in this study, which might suggest that beneficial fungus could elicit weaker gene expression changes compared to pathogen-induced responses . The results in this study also showed that defense-related genes were suppressed by S. luteus but were induced by H. annosum , indicating that S. luteus promoted mutualistic interaction by suppressing plant defense responses. H. annosum infection induced unique gene expression patterns in PR proteins, phenylpropanoid pathway/lignin biosynthesis, flavonoid biosynthesis, chalcone/stilbene biosynthesis, while ECM fungus inoculation repressed defense-related genes (peroxidases, laccases), receptor-like protein kinases, methyltransferases, germin-like proteins (GLPs). Methyltransferases work on cytosine methylation that influences gene expression and represses transcription . Plant GLPs are associated with enzymatic activities including oxalate oxidase (OxO), superoxide dismutase (SOD), and ADP glucose pyrophosphatase (AGPPase) , playing crucial roles in disease resistance and defense responses under biotic stress . GLP2 was induced in Norway spruce trees in response to Heterobasidion infection . Unlike in plant-pathogenic interaction wherein plant immunity can be triggered against pathogen infection, plant immunity is often suppressed in the plant-mutualistic interaction to facilitate successful colonization . For example, peroxidase activity in Norway spruce roots was induced in response to pathogenic Ceratocystis polonica but was evaded or suppressed during interaction with the ECM fungus L. bicolor . In P. sylvestris - L. bicolor interaction, genes involved in cell wall modification (XTH and β-xylosidase) were expressed and antifungal α-pinene synthase was downregulated . The support for our observation was previously noted in Populus and L.bicolor interaction where poplar JA-responsive defense gene expressions were blocked by symbiotic effectors (MiSSP7) from L. bicolor . This gene prevented the JA repressor PtJAZ6 degradation during symbiosis development . The symbiotic effector promotes the symbiotic interaction probably through maintaining the repression of transcription factor PtMYC2.1‐regulated genes . Overexpression of poplar MYC2s impaired the fungal growth and the formation of Hartig net in planta, activating the expression of defensive genes encoding terpene synthases, chitinases, GLPs, LRR-RLKs, β-glucosidase and ERF/AP2 . Furthermore, additional supporting evidence to our study is found in oak-ECM fungi interaction. In this system, oak growth was enhanced by three EMC fungi P. microcarpus , P. involutus and L. bicolor, with a common reduction of core DEGs in colonized roots including genes encoding proteins involved in carbon metabolism, defense responses, phenolic pathways and transport . Local host defenses may be activated transiently by MAMPs of ECM fungi like chitins, but plant defense genes could be repressed at the later developmental stage to benefit ECM fungal growth . Section title: Discussion Educational score: 4.2024431228637695 Domain: biomedical Document type: Study Language: en In this study, S. luteus inoculation induced genes related to nutrient transporters, such as amino acids, nitrates, sugar, and magnesium. This may indicate the fungus could promote plant growth by enhancing nutrient uptake. During poplar— L. bicolor interaction, ethylene and jasmonic acid pathways were induced at the late stage of root colonization to limit fungal growth within roots . The induction of terpene synthases, cytochrome P450s, LOX, MPAK by S. luteus inoculation in our study may suggest that plant limited S. luteus growth in roots by terpene biosynthesis pathway and hormone signaling. Auxin signaling was activated in poplar during L. bicolor colonization, which could facilitate root growth . In our study, defense response-related genes and cell wall modification-related genes were induced by co-inoculation, suggesting plants had balancing buffering defense responses and growth under co-inoculation. Auxin homoeostasis-related genes (WAT1-relaterd proteins, auxin-responsive protein SAUR32) were upregulated in SlHa, which may contribute to the primary root growth. Section title: Conclusions Educational score: 3.2932541370391846 Domain: biomedical Document type: Study Language: en S. luteus promoted mutualistic interaction by suppressing plant defense responses. Pre-inoculation of Scots pine seedlings with beneficial fungus S. luteus prior to pathogen challenge promoted primary root growth, as well as had a balancing buffering role in plant defense responses and cell growth at transcriptome level. Section title: Supplementary Information Educational score: 4.249914646148682 Domain: biomedical Document type: Study Language: en Additional file 1. Dual culture of S. luteus and H. annosum on MMN agar media. S. luteus had grown for 13 days prior to the inoculation of H. annosum . Photos were taken 7 days and 17 days after H. annosum colonization. Additional file 2. All seedlings that were recorded from all treatments. Information includes ID, primary root length, and lateral root number. NA refers to not available. Additional file 3. Normalized counts that were obtained by DESeq2's median of ratios. Additional file 4. Hierarchical clustering of DEGs using log2(1 + TMM-normalized CPM). CPM: Counts per million. CPM = raw count of each gene/lib.size of each sample. We keep genes that are expressed at least 1 CPM in at least 3 libraries in differential gene expression analysis using EdgeR. Ctr: control seedlings without any inoculum. Ha: pathogen-infected seedlings. Sl: Suillus luteus -infected seedlings. SlHa: co-infected seedlings with both S. luteus and H.annosum . ‘ + ’ refers to upregulated, while ‘-’ refers to downregulation. Ha.Sl.SlHa: + + + refers to DEGs that were upregulated in all treatments compared to Ctr. Ha.Sl: + + refers to DEGs that were upregulated both in Ha and in Sl. Ha.SlHa: +—refers to DEGs that were upregulated in Ha but downregulated in SlHa. The value on the scale bar refers to log2(1 + TMM-normalized CPM). Additional file 5. Summary of DEGs into common genes in three treatments, genes overlapped in two treatments, and treatment-specific genes based on the data from the Venn diagram in Fig. 4 A. The data in each file included Gene ID, TMM-normalized CPM in replicates of each treatment, logFC, FDR, protein family, and protein name. ‘1’ refers to upregulated, while ‘0’ refers to downregulation. 31_000 refers to DEGs that were upregulated in all treatments compared to Ctr. 32_11 refers to DEGs that were upregulated in both Ha and in Sl. 330_1 refers to DEGs that were specifically upregulated in Ha. Additional file 6. Best hit selected by bit score for each CDS sequence of DEGs which blast against to Scots pine de novo transcriptome assembly fasta sequences constructed with Trinity . Additional file 7. Heatmap of DEGs which were specifically upregulated in Ha. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *). Additional file 8. Heatmap of DEGs which were specifically downregulated in Ha. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *). Additional file 9. Heatmap of DEGs which were specifically downregulated in Sl. Red indicates a high level of upregulation, while blue indicates high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *). Additional file 10. Heatmap of DEGs using log2foldchange which were upregulated in both Sl and SlHa. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *). Additional file 11. Heatmap of DEGs using log2foldchange which were downregulated in both Sl and SlHa. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *). Additional file 12. Heatmap of DEGs which were specifically upregulated in SlHa. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *). Additional file 13. Heatmap of DEGs which were specifically downregulated in SlHa. Red indicates a high level of upregulation, while blue indicates a high level of downregulation. Asterisks indicate whether significant difference exists in gene expression level of treatment such as Ha, Sl, SlHa compared to that of Ctr. ( p < 0.05: *). | Study | biomedical | en | 0.999995 |
PMC11697948 | Section title: Background Educational score: 4.062765121459961 Domain: biomedical Document type: Review Language: en Parkinson’s Disease (PD) is currently the fastest-growing neurological disorder globally, second only to dementia . Worldwide prevalence has doubled over the past 25 years, now exceeding 8.5 million individuals . It is a progressive neurological disorder due to substantia nigra cell loss, reducing dopamine production . Dopamine deficiency leads to motor symptoms like tremors, bradykinesia, gait issues, and rigidity , and non-motor symptoms including speech problems, urinary issues, constipation, sleep disturbances, and neuropsychiatric symptoms . These worsen over time, impacting patients’ quality of life . Symptoms of PD, especially those affecting emotional expression and recognition such as facial masking greatly contributes to stigma . Section title: Background Educational score: 3.6842243671417236 Domain: biomedical Document type: Other Language: en Stigma plays a significant role in the lives of individuals living with Parkinson’s disease as it is a complex social phenomenon encompassing stereotypes, prejudice, discrimination, and exclusion . It differs from shame, which is an emotional response characterised by a deep sense of personal inadequacy or dishonour . While stigma refers to the negative social perception imposed by others due to a particular condition, shame is more personal, stemming from internalised beliefs about one’s own worth or behaviour. Thus, while stigma is shaped by societal attitudes, shame is a self-directed feeling that can compound the challenges faced by individuals with PD . Section title: Background Educational score: 3.444744825363159 Domain: biomedical Document type: Other Language: en Stigma can manifest in several forms, each affecting individuals in unique ways. Felt stigma refers to the perception that others view a person negatively due to their condition, leading to feelings of anticipated discrimination or exclusion . Enacted stigma, on the other hand, involves actual discriminatory actions or behaviours directed at the individual based on their condition . Affiliated stigma affects caregivers who may experience stigma due to their association with someone living with a stigmatised condition . Lastly, self-stigma occurs when individuals internalise negative beliefs and judgements about themselves, leading to shame, guilt, and a diminished sense of self-worth . These different forms of stigma combine to create complex social and emotional challenges for those affected. Section title: Background Educational score: 3.509385347366333 Domain: biomedical Document type: Review Language: en One study exploring stigma in PD reports more than 50% of people with Parkinson’s disease conceal their diagnosis, mask symptoms or avoid appearing in public due to stigma. A major contributing factor to this stigma is the lack of public awareness and understanding of PD and its symptoms, such as tremors, slow movement, and facial masking . These symptoms are often misinterpreted by the public, leading to misconceptions about the capabilities and behaviours of those with PD . Within the context of this review, the public refers to individuals in society who are not directly affected by PD. Section title: Background Educational score: 3.6894776821136475 Domain: biomedical Document type: Review Language: en As a result of these misunderstandings, individuals with PD and their caregivers frequently face social stigmatisation. This stigmatisation can manifest in various ways, such as being unfairly judged, socially isolated, or excluded from community activities. The impact of stigma on the lives of people with Parkinson’s disease is profound, affecting their quality of life and mental health . Research indicates that stigma in PD can lead to increased levels of depression, anxiety, and social isolation among those living with the disease . Another study highlights the wider health and social impacts of PD stigma, aggravating poverty due to loss of income, increasing severity of disability and sometimes resulting in mortality. Section title: Background Educational score: 3.8289616107940674 Domain: biomedical Document type: Review Language: en Research on the stigma associated with PD remains limited, despite evidence indicating that stigma can profoundly affect the social and psychological well-being of individuals with Parkinson’s disease. While studies such as Maffoni et al. and Lubomski et al. have explored the experience of stigma in PD, their scope and methodologies reveal gaps. Maffoni et al. conducted a review focused solely on qualitative studies, providing insights into patients’ experiences of stigma but limiting broader generalisability and cross-study comparison. Similarly, Lubomski et al. highlighted stigma as a barrier to care, yet primarily within healthcare settings rather than the broader community. Section title: Background Educational score: 4.052065849304199 Domain: biomedical Document type: Review Language: en Most existing literature emphasises medical symptoms and treatment options for PD, leaving a lack of comprehensive research into the social and psychological dimensions, including the impact of public and community-based stigma. This review addresses these limitations by employing a mixed-methods approach to synthesise both quantitative and qualitative findings across diverse settings, with a focus on the stigma encountered in everyday social contexts. Filling this gap is essential to developing targeted, evidence-based interventions aimed at reducing stigma and improving the quality of life for individuals with PD and their caregivers. Section title: Background Educational score: 3.95694899559021 Domain: biomedical Document type: Review Language: en This systematic review aims to explore PD-related stigma, examining its impact on individuals and their caregivers, and identifying potential interventions to reduce stigma by synthesising existing literature. By understanding the stigma associated with PD, we can determine the extent of the problem and provide recommendations to address it. This will help raise public awareness and promote PD stigma as an important public health issue, ultimately improving the lives of those affected and fostering a more inclusive and supportive society. Section title: Background Educational score: 4.0406413078308105 Domain: biomedical Document type: Review Language: en This will be achieved through the following objectives; first, to conduct a comprehensive systematic review and synthesise relevant empirical research on PD-related stigma, drawing from multiple databases. Second, to identify recurring themes, patterns, and trends in the literature concerning the experiences of stigma and its impact on individuals affected by PD. Finally, to provide evidence-based recommendations for future research and stigma-reduction strategies, offering targeted interventions to support individuals with PD in addressing and overcoming social stigma. These objectives aim to enhance understanding and inform future efforts to improve the well-being of those impacted by PD. Section title: Methods Educational score: 4.022715091705322 Domain: biomedical Document type: Review Language: en A systematic review was conducted following the Joanna Briggs Institute methodology for Mixed-Methods Systematic Reviews guidance . It is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to enhance the quality and transparency of reporting. The review protocol was registered on PROSPERO register of systematic reviews on 13th November 2023 . The PRISMA 2020 Checklist can be seen in Additional File 1 . Section title: Search strategy and selection criteria Educational score: 3.3249595165252686 Domain: biomedical Document type: Study Language: en Six databases were searched up to August 2024. These were CINAHL, Medline, Embase, PsycINFO, Web of Science and the Cochrane Library. These databases were chosen as their literature focusses on nursing, medicine, psychology, and social sciences. A search of the following websites was also conducted to source relevant grey literature: EThOS, PLOS, NICE and WHO. Reference lists of all included studies were manually searched to identify additional studies not found in the initial search. Internet search engines Google ( https://www.google.co.uk/ ) and Google Scholar ( https://scholar.google.com/ ) were extensively searched for peer-reviewed publications. The search was supplemented by journal alerts from Parkinson’s specific journals such as Journal of Parkinson’s Disease and Parkinsonism and Related Disorders. Section title: Search strategy and selection criteria Educational score: 3.7822725772857666 Domain: biomedical Document type: Study Language: en Keywords used to conduct the search were based on three main dimensions: Parkinson’s disease, stigma (and related terms) and public perception. These keywords were carefully selected to capture a broad range of articles related to Parkinson’s disease and the associated stigma. Using variations of “Parkinson’s disease” ensured that different terminologies that may be used in academic literature were covered, while the terms related to stigma and discrimination were chosen to encompass the different dimensions of stigma that individuals with PD may experience. Terms related to public perception helped to identify articles that examined societal views and misconceptions, and discussed the social dimensions of living with PD. The truncation wildcard (*) was used on key words, allowing alternate forms of the word to be searched . All search terms and Boolean logic can be seen in Additional File 2 . Section title: Identification of studies Educational score: 3.923457384109497 Domain: biomedical Document type: Review Language: en In this review, research exploring the stigma experienced by people affected by PD was of interest. Research incorporating people with Parkinson’s disease and their carers were included. Carers often share in the challenges of PD, therefore they were included to provide a comprehensive view of stigma’s impact on both individuals with PD and those who support them. In studies where the experiences of people with Parkinson’s disease was examined alongside other conditions, data were extracted only about PD without limitations. No data limitations were put in place during database searches. A summary of the inclusion/exclusion criteria used is provided in Table 1 . Section title: Identification of studies Educational score: 2.7349202632904053 Domain: biomedical Document type: Study Language: en Table 1 Inclusion/exclusion criteria Inclusion Exclusion • Empirical research on the experiences of people living with Parkinson’s disease or their carers • Grey literature including thesis, dissertation, or full text of conference abstracts • English articles • People who do not have PD or people who are not carers for Parkinson’s disease • Non-empirical research • Commentary papers • Literature reviews/systematic reviews (excluded but reference lists searched for potential papers) • Studies about other neurological conditions not including PD Section title: Study selection Educational score: 3.9805681705474854 Domain: biomedical Document type: Study Language: en The systematic review software Covidence was used to assist in the removal of duplicates, screening, and data extraction . Studies were imported and duplicates were removed. The inclusion and exclusion criteria were used to screen papers within Covidence and determine relevance to this review. Stage 1 of screening involved examining studies by title and abstract, with the primary screening conducted by SC. To enhance reliability, a sample of 25% of studies was also checked by GC, serving as a secondary reviewer to reduce potential bias and improve consistency in selection. The 25% sample size was chosen as a manageable proportion for cross-checking while providing a robust reliability measure across the dataset. Stage 2 involved screening of full text studies by SC and GC independently. At this stage, both researchers (SC & GC) screened 100% of full text studies. Conflicts throughout the screening process were resolved following discussion with GM. Section title: Quality appraisal Educational score: 4.1201324462890625 Domain: biomedical Document type: Review Language: en The quality of papers included in the review was appraised using the Joanna Briggs Institute (JBI) Critical Appraisal Tool. Qualitative studies were evaluated with the JBI checklist for qualitative research , while quantitative studies were assessed using the JBI checklist for analytical cross-sectional studies. Covidence software was used to manage and streamline the appraisal process, allowing reviewers to independently assess each study. In cases where there were disagreements between reviewers, a third reviewer was consulted to resolve discrepancies, ensuring an unbiased evaluation. To further enhance reliability, inter-rater agreement was calculated using Cohen’s kappa , which provided a quantitative measure of consistency between reviewers. Twelve studies were deemed to be of high quality [ 28 – 39 ] and the remaining ten were medium quality [ 19 , 40 – 48 ]. No studies were deemed as low quality, therefore were not excluded. Section title: Data synthesis and analysis method Educational score: 3.976778268814087 Domain: biomedical Document type: Review Language: en This review adopts a mixed methods approach, encompassing both qualitative and quantitative studies. Narrative synthesis, as defined by Popay et al. , involves using language and text to summarise and present findings across multiple studies, adopting a textual or ‘storytelling’ approach. It is a robust scientific approach that facilitates the integration of both quantitative and qualitative data related to a specific phenomenon . Narrative synthesis was used for this systematic review and was conducted by the researcher (SC). Section title: Data synthesis and analysis method Educational score: 4.063128471374512 Domain: biomedical Document type: Review Language: en In this systematic review, both qualitative and quantitative methods of analysis were employed to provide a comprehensive synthesis of the included studies. For the qualitative component Braun and Clarke’s thematic analysis was used to systematically identify and categorise recurring patterns and themes within the findings. This involved coding the qualitative data from each study, organising these codes into broader themes, and refining these themes using NVivo 11. Section title: Data synthesis and analysis method Educational score: 4.009152412414551 Domain: biomedical Document type: Review Language: en For the quantitative studies, the findings were converted to comprise textual descriptions or narrative views of quantitative results, allowing for a more holistic understanding of the data. This conversion process enabled the integration of quantitative findings into the broader narrative framework of the review. The integration of qualitative and quantitative data was achieved through a mixed methods synthesis, following the JBI methodology for Mixed-Methods Systematic Reviews . This approach allowed the triangulation of the data, enhancing the robustness and validity of our conclusions. Section title: Study characteristics Educational score: 4.168659210205078 Domain: biomedical Document type: Review Language: en The review PRISMA flowchart is presented in Additional File 3 . A total of 5441 studies were imported into Covidence and 1190 duplicates were removed. The inclusion and exclusion criteria were used to screen papers within Covidence and determine relevance to this review. Firstly, 4252 studies were screened by title and abstract (SC) and a sample checked (GC). In total, 4206 studies were determined irrelevant for this review, leaving a remaining 46 studies for full text screening. In total, 24 studies were excluded due to providing outcomes not relevant to the review ( n = 15), interventions based on disease management ( n = 2), the population did not focus on PD ( n = 2), and not empirical research ( n = 2). Literature reviews ( n = 3) were also excluded however, reference lists were screened for papers that may not have shown during the database search that may be suitable for the review. During the reference list search, one study was determined suitable for the review after title, abstract and full text screening. A final total of 22 papers were deemed suitable for this review. A full PRISMA flow chart can be seen in Additional File 3 . Section title: Study characteristics Educational score: 3.908841371536255 Domain: biomedical Document type: Review Language: en This review included 22 research studies published between 2002 and 2024. Of these, 11 used a qualitative design, and the remaining 11 employed a quantitative approach. Eleven studies in the review had a cross-sectional design using questionnaires, one using a cohort design via a 3-year prospective study and 11 used a qualitative approach using interviews and focus groups. A table of study characteristics can be seen in Additional File 4 . Section title: Study characteristics Educational score: 3.6034281253814697 Domain: biomedical Document type: Study Language: en The included studies took place in various geographical locations: seven studies in the USA [ 34 , 36 – 38 , 41 , 42 , 47 , 48 ], four in the UK , two in China , two in Brazil , and one each in Mexico , Israel , Sweden , Kenya , Tanzania , Jordan , Taiwan and France . The studies were conducted in diverse settings, including participant homes, clinics, cafes, PD support groups, hospitals, academic medical centres, and online platforms. The geographic diversity of these studies suggests that the results may be shaped by differences in healthcare systems, cultural beliefs, and participant characteristics, all of which could affect the outcomes and limit the generalisability of the findings. Section title: Study characteristics Educational score: 3.9401767253875732 Domain: biomedical Document type: Study Language: en Sample sizes ranged from six to 362 participants with a combined total of 2,502 participants. Studies included samples of people with Parkinson’s disease [ 19 , 29 – 33 , 35 – 41 , 43 – 48 ], spouses/carers of people with Parkinson’s disease , healthcare workers and traditional healers . All studies included both female and male participants, apart from one study that only included female participants. The mean age of participants in the included studies was 65.1 years old, with the range being 30–94 years old. Mean disease duration of participants was 8 years. The variability in sample sizes across studies may introduce bias, as smaller samples could result in less reliable or less generalisable findings. Additionally, studies with larger samples may overrepresent certain characteristics, skewing the results. This variation was considered when interpreting the overall findings as it could influence the accuracy and applicability of the conclusions drawn from these studies. Section title: Study characteristics Educational score: 3.6394741535186768 Domain: biomedical Document type: Review Language: en All 22 studies reported obtaining ethical approval from appropriate review bodies. In total, 21 studies included information about informed consent processes. One study by Hermanns did not include information about obtaining informed consent from participants for the study. This omission of informed consent can raise ethical concerns and lead to potential bias as participants may not fully understand their involvement in the study. Six studies reported conducting the studies in accordance with the Declaration of Helsinki , and six maintained confidentiality and anonymity throughout the study . Three studies reported voluntary participation . A thorough review of included studies in this review revealed no significant ethical concerns. Section title: Qualitative studies Educational score: 2.076608419418335 Domain: biomedical Document type: Study Language: en Ten papers adopting a qualitative approach used individual interviews to collect data [ 19 , 29 , 30 , 40 – 46 ]. Of these, some combined interviews with other methods such as focus groups , observations , and questionnaires . One study by AboJabel et al. used only focus groups for the data collection method. Section title: Qualitative studies Educational score: 2.1533501148223877 Domain: biomedical Document type: Study Language: en The qualitative data collection took place in a variety of settings including participant homes , clinics and cafés and PD support groups . Seven studies did not mention where interviews took place [ 28 – 30 , 41 , 44 – 46 ]. Use of an interview guide was discussed in six studies [ 28 – 30 , 41 , 43 , 46 ], four of which included the interview guide within supplementary material . Researchers conducted the interviews in seven studies [ 19 , 28 – 30 , 41 , 43 , 44 ]. The remaining qualitative studies did not mention who conducted the interviews within the studies. Section title: Quantitative studies Educational score: 2.73475980758667 Domain: biomedical Document type: Review Language: en All eleven quantitative studies included in the review used questionnaires to collect data. Three collected data via an online questionnaire , two studies collected questionnaire data in hospitals , one combined both , and one in a public academic medical centre . These studies used self-completion questionnaires for data collection. The remaining four studies did not mention by what means the questionnaire data were collected . Section title: Quantitative studies Educational score: 4.000596046447754 Domain: biomedical Document type: Study Language: en Across the studies, 24 different outcome measurements were used. The Parkinson’s Disease Questionnaire (PDQ-39) was the most common instrument, being used by seven studies [ 32 , 36 – 39 , 47 , 48 ]. This questionnaire includes 39 items assessing how often people with Parkinson’s disease experience difficulties across eight dimensions of daily living including relationships, social situations and communication. It also assesses the impact of Parkinson’s on specific dimensions of functioning and wellbeing. Of these studies, six used PDQ-39 and one used PDQ-8 which is a shorter version with eight items. Both versions of the PDQ are validated instruments that have been widely used for assessing the quality of life for people with Parkinson’s disease. Section title: Quantitative studies Educational score: 1.8540056943893433 Domain: biomedical Document type: Study Language: en Several other validated scales were used in the studies reviewed to assess various aspects of PD. The most common scales are shown in Additional File 5 . Section title: Study results Educational score: 4.021607398986816 Domain: biomedical Document type: Study Language: en Through the process of data analysis and synthesis, five distinct themes emerged. The first theme, stereotypes in Parkinson’s disease , examines the common misconceptions, preconceived notions, and prevailing stereotypes surrounding individuals with PD within the broader societal context. The second theme, drivers and facilitators of stigma , explores the underlying societal, cultural, and psychological mechanisms that foster stigmatising attitudes and behaviours towards individuals living with PD. The third theme addresses the impact of stigma on mental health and well-being , including feelings of embarrassment and shame associated with the stigma of PD. The fourth theme, response and consequences of stigma , considers the strategies adopted by those with PD to cope with public stigma. Finally, the fifth theme, beyond stigma , sheds a more positive light on the impact of living with PD, offering a comprehensive understanding of the condition. Section title: Theme one: stereotypes in Parkinson’s disease Educational score: 2.19685435295105 Domain: biomedical Document type: Study Language: en Across all studies, participants highlighted the prevalence of stereotypes and misconceptions about PD in the public domain [ 19 , 28 – 48 ]. These misconceptions often led to stigmatising behaviours, such as avoidance and discrimination, directed toward individuals with PD and their caregivers. Section title: Visible symptoms as the defining characteristic Educational score: 3.6307873725891113 Domain: biomedical Document type: Study Language: en One prevalent stereotype is the misconception that PD is defined solely by visible motor symptoms, particularly tremor . Participants expressed frustration over this oversimplification, emphasising the lack of awareness regarding other symptoms of PD, particularly non-motor symptoms. For instance, one study reported that participants noted the public’s limited understanding of non-motor symptoms such as speech disorders and muscle stiffness, which undermines the complexity of PD. “I think it (the perception of the illness) is overly related to the tremors. Nobody understands the suffering caused by muscle stiffness” ( p.3) Section title: Visible symptoms as the defining characteristic Educational score: 3.9162981510162354 Domain: biomedical Document type: Study Language: en The literature also indicated that difficulties with activities of daily living (ADLs) and motor symptoms were associated with higher levels of stigma in individuals with PD. One study found that ADL difficulties contributed to greater stigma, and another linked independence in ADLs to lower levels of stigma. Lin et al. demonstrated that impairment in ADLs, motor examination scores, and non-motor symptoms correlated with higher levels of self-stigma. Furthermore, Ma et al. noted that difficulties with facial expression, a common PD symptom, tended to increase feelings of stigma and reduce quality of life. Another study found significant associations between motor symptoms and both self-stigma and enacted stigma. Section title: Age stereotyping and misconceptions Educational score: 3.3551266193389893 Domain: biomedical Document type: Study Language: en Another common stereotype was the belief that PD exclusively affected older individuals . This ageist stereotype was perceived to lead to delayed diagnoses and misinterpretation of symptoms, particularly in younger individuals. Participants reported encountering disbelief or scepticism from others upon disclosing their diagnosis, often leading to concealment of their condition to avoid judgement . Healthcare professionals’ biases further contributed to perceived ageist stereotypes and delayed treatment . Media portrayals emphasising advanced-stage symptoms also were noted to skew public perceptions of PD. “Everyone stands there not understanding how such a thing can occur (the disease befalling a young person).” ( ; p. 3). Section title: Age stereotyping and misconceptions Educational score: 2.5024120807647705 Domain: biomedical Document type: Study Language: en Quantitative research supported these findings, with two studies reporting associations between age and stigma, particularly among females. One study found that older individuals reported lower levels of perceived and experienced stigma than younger individuals, while another study identified younger age as a predictor of self-perceived stigma, especially among men. Section title: Supernatural beliefs and alternative explanations Educational score: 2.663501024246216 Domain: biomedical Document type: Study Language: en Supernatural beliefs, including witchcraft or curses, were also identified as alternative explanations for PD symptoms . Participants in these studies reported that such beliefs contributed to the stigmatisation of individuals with PD, portraying them as afflicted by malevolent forces or feigning symptoms, leading to social isolation and discrimination. These misconceptions were felt to not only undermine the understanding of PD but also exacerbate the stigma and challenges faced by those living with the condition. “people think [the person with Parkinson’s] is bewitched or they think she is pretending or she’s drunk” and “there’s no way you’re going to convince such people that this person is just sick. The most meaningful [explanation] is witchcraft” ( ; p. 5) Section title: Theme two: drivers and facilitators of stigma Educational score: 1.7880269289016724 Domain: biomedical Document type: Other Language: en Stigma surrounding PD was shaped by various drivers and facilitators, contributing to negative public perceptions and attitudes toward individuals affected by the condition. Section title: Time since diagnosis and disease severity Educational score: 4.0104241371154785 Domain: biomedical Document type: Study Language: en Stigma experiences in individuals with PD were noted to be influenced by time since diagnosis and disease severity. One study found that as the number of years since diagnosis increased, individuals reported higher levels of felt, enacted, and total stigma, which suggested more pronounced stigma in later stages. Hou et al. also found disease duration to be significantly associated with stigma in PD with Stigma Scale for Chronic Illness (SSCI) score ( p = 0.003) and felt stigma (= 0.004), particularly in males (p = < 0.001). Additionally, Ma et al. found that all stigma measures correlated with disease severity, with more severe PD being linked to increased stigma and poorer quality of life (p = < 0.05). Conversely, Salazar et al. found no significant contribution of disease characteristics to stigma perception, indicating a complex and multifaceted experience of stigma in PD. Section title: Presence of additional health conditions Educational score: 4.066683292388916 Domain: biomedical Document type: Study Language: en Comorbidities, especially mental health issues, exacerbated stigma in PD patients. One study reported that 79% of PD patients had additional health conditions, such as thyroid disease, depression, and anxiety, which correlated with higher stigma levels and lower quality of life. They demonstrated that depression and anxiety showed strong positive relationships with stigma ( p < 0.001). Another study also found significant associations between anxiety, depression, and stigma with higher SSCI scores (p = < 0.001) and higher felt stigma ( p = 0.001). These results showed these emotional challenges are closely linked to how much stigma people feel. This study also measured affiliate stigma, which refers to the stigma experienced by individuals who are closely associated with someone who has a stigmatised condition, such as a caregiver . Mental health issues were significant predictors of affiliate stigma ( p = 0.187) , highlighting their impact on stigma in PD. Section title: Lack of public awareness and education Educational score: 3.7248618602752686 Domain: biomedical Document type: Review Language: en A prominent driver of stigma identified in the review was the lack of awareness and education about PD within communities [ 19 , 29 , 42 – 44 ]. Participants noted that misconceptions and misinformation about PD led to stigmatisation. One study emphasised the absence of public information about PD, resulting in stereotypes and stigma. Another reported that many people were unaware of what PD entailed, perpetuating misconceptions and hindering early diagnosis and intervention. Similarly, one participant from Valcarenghi et al. remarked: “One thing I’ve learned is that many people do not know what Parkinson’s disease is.“( ; p.275). Section title: Misattributions and cultural beliefs Educational score: 1.5657023191452026 Domain: other Document type: Other Language: en Misattributions of PD symptoms to aging, clumsiness, or cold weather contribute to stigmatisation . Cultural beliefs, such as witchcraft or curses, further exacerbated stigma. “There’s that whole thing of whatever you don’t understand is witchcraft.Some spirits are behind this whole thing” ( ; p.5) Section title: Misattributions and cultural beliefs Educational score: 3.3755831718444824 Domain: biomedical Document type: Study Language: en Participants in Fothergill-Misbah’s study reported cultural beliefs as drivers of stigma, with some attributing PD to supernatural causes. These beliefs, often linked to blame and punishment, notably impacted individuals with PD, leading to social isolation and discrimination. Shah et al. highlighted the role of cultural ideologies in stigmatising PD, with participants reluctant to disclose their condition due to associated shame or taboo. “And there is a stigma attached to the condition back home , where I come from. Wherein , no one tends to divulge–well actually it’s a private information , like my condition. So , nobody would like , even my family wouldn’t like to tell anybody else that I’m having this condition. So , it’s better off taking me as a drunk , rather than a PD patient.” ( ; p. 11). Section title: Public perception and media representation Educational score: 1.9527883529663086 Domain: biomedical Document type: Other Language: en Media representation was noted to influence public perception of PD, often focusing on advanced-stage symptoms and celebrity narratives . This skewed portrayal led to misconceptions and further stigmatised individuals with PD. Two studies noted the absence of media representation and public awareness about PD, highlighting the need for better public education to reduce stigma. “I’ve never heard anybody , [Parkinson’s has] never been featured in the newspapers , no doctors talk about it the way they talk about anything else. There is no awareness about it at all”. ( ; p. 5). Section title: Public perception and media representation Educational score: 3.205796957015991 Domain: biomedical Document type: Other Language: en In summary, stigma surrounding PD is driven by factors such as time since diagnosis, disease severity, comorbidities, lack of public awareness, cultural beliefs, healthcare system limitations, and media representation. Addressing these issues through public education, improved healthcare training, and accurate media portrayal can help mitigate stigma and improve the quality of life for individuals with PD. Section title: Theme three: impact of stigma on mental health and well-being Educational score: 1.9303916692733765 Domain: biomedical Document type: Other Language: en Stigma surrounding PD was seen to considerably impact the mental health and well-being of affected individuals, exacerbating feelings of shame, embarrassment, and social isolation. Section title: Feelings of shame and embarrassment Educational score: 2.217036485671997 Domain: biomedical Document type: Study Language: en Stigma induced profound feelings of shame and embarrassment among individuals with PD, as highlighted in several studies . Participants expressed concerns about being perceived as incompetent, leading to self-stigmatisation and a desire to conceal their condition. For example, one participant in Caap-Ahlgreen et al. stated: Section title: Feelings of shame and embarrassment Educational score: 1.0237385034561157 Domain: other Document type: Other Language: en “ People around me think I am incompetent; think I am an idiot” ( ; p. 90). Section title: Feelings of shame and embarrassment Educational score: 1.8003722429275513 Domain: biomedical Document type: Study Language: en Another participant in one study expressed embarrassment about her symptoms: “ One person did see me shake and go , ‘Oh my god , I hope it’s not Parkinson’s’” ( ; p. 64). Section title: Feelings of shame and embarrassment Educational score: 1.5959733724594116 Domain: biomedical Document type: Other Language: en This sense of shame often resulted in social withdrawal, avoidance of public spaces, and diminished self-esteem, worsening mental health. Section title: Feelings of shame and embarrassment Educational score: 1.9154890775680542 Domain: biomedical Document type: Study Language: en Stigma also contributed to the loss of independence for individuals with PD, further exacerbating feelings of shame. Participants in one study discussed struggles with maintaining autonomy, with one stating: Section title: Feelings of shame and embarrassment Educational score: 1.0184088945388794 Domain: other Document type: Other Language: en “ The loss of my independence was , very very hard to bear” ( ; p. 293). Section title: Feelings of shame and embarrassment Educational score: 1.3660560846328735 Domain: other Document type: Other Language: en This loss of independence was noted to intensify the emotional burden and contributed to a diminished sense of identity and self-worth . Section title: Impact on social and work life Educational score: 2.6253159046173096 Domain: biomedical Document type: Study Language: en Stigma associated with PD extended to social networks and the workplace, worsening feelings of self-stigma and isolation. Participants reported discomfort among friends, family, and colleagues due to PD’s physical symptoms, leading to self-consciousness and avoidance of social interactions. One study noted unease among friends and family members, contributing to participants’ social withdrawal. In another study , participants avoided public spaces due to embarrassment, with one stating: “I tend to stick to my room, rather than go anywhere. I feel a little bit embarrassed as well to go out because I feel low” (; p. 10). Section title: Impact on social and work life Educational score: 2.0779707431793213 Domain: biomedical Document type: Study Language: en In the workplace, individuals with PD faced stigma from co-workers, leading to self-stigmatisation and reluctance to disclose their condition. One participant expressed frustration about explaining the disease at work, wishing for a badge that says, “don’t ask, I have Parkinson’s disease” (p. 64). This fear of judgment and discrimination was seen to diminish self-confidence and to contribute to frustration and isolation. Section title: Impact on social and work life Educational score: 2.1792967319488525 Domain: biomedical Document type: Other Language: en Stigma also leads to social withdrawal and isolation, contributing to feelings of loneliness and depression among individuals with PD . Participants described withdrawing from social activities due to fear of judgment, which then perpetuated feelings of depression and anxiety. Section title: Theme four: response and consequences of stigma Educational score: 1.8687824010849 Domain: biomedical Document type: Other Language: en Despite the challenges posed by stigma, individuals with PD employed various strategies to manage its impact on their lives, including seeking social support, engaging in advocacy efforts, and adopting adaptive coping mechanisms to navigate social interactions and mitigate stigma . Section title: Response strategies to stigma Educational score: 2.0248982906341553 Domain: biomedical Document type: Study Language: en Individuals with PD used diverse strategies to cope with public stigma, from concealing symptoms to avoiding social situations. Participants described efforts to hide their symptoms in public, such as holding onto purse straps or keeping hands in pockets to conceal tremors . Some individuals even relocated to escape scrutiny, with one participant noting: “Sold the house. Would be good to leave this area” ( ; p. 93). Section title: Response strategies to stigma Educational score: 1.6321921348571777 Domain: other Document type: Other Language: en Avoidance strategies, like restricting social activities to essential events only, were also common, especially among women. One participant explained: “The disease has affected my social life hugely as I get embarrassed because of the symptoms. I do not leave home unless it’s very necessary” ( ; p. 76). Section title: Consequences of stigma on social interactions Educational score: 1.9631110429763794 Domain: other Document type: Study Language: en Stigma deeply impacted social interactions, contributing to social isolation and withdrawal from community engagement . Participants reported feeling watched and judged, leading to heightened self-consciousness and discomfort in public spaces . Workplace stigma further exacerbated social isolation, with individuals reluctant to disclose their condition due to fear of negative reactions from colleagues . This avoidance of public spaces and social interactions resulted in a diminished quality of life. One participant reported: “Over the last year , I’ve become more withdrawn. I don’t want people to see me. I’m afraid to see how people look at me” ( ; p. 16). Section title: Psychological consequences of stigma Educational score: 3.725985288619995 Domain: biomedical Document type: Study Language: en The psychological impact of stigma on individuals with PD was profound, leading to feelings of shame, embarrassment, and low self-esteem . Participants described internalised stigma from societal beliefs about their capabilities, leading to feelings of inadequacy and worthlessness . Depression, anxiety, and loneliness were common, exacerbated by public stigma . Stigma-induced psychological distress hindered individuals’ ability to seek social support and engage in meaningful activities, perpetuating a cycle of social isolation and diminished well-being. Section title: Psychological consequences of stigma Educational score: 4.093287467956543 Domain: biomedical Document type: Study Language: en Self-compassion plays a crucial role in mitigating the negative impact of stigma on mental health. One study found that higher levels of self-compassion were associated with lower levels of depression, anxiety, and stress, both independently and through a significant indirect effect on felt stigma (p = < 0.001). However, self-compassion did not moderate the relationship between enacted stigma and mental health outcomes (p = < 0.00). Emotional well-being was significantly associated with stigma ( p = 0.12) , and mental health symptoms contributed to experiences of stigma ( p = 0.187) . Individuals with PD who experience stigma tended to have more severe depression and poorer quality of life (p = < 0.05) . Similarly, one study also found higher stigma severity to be an associated factor of depression in both people with Parkinson’s disease ( p = 0.001) and their caregivers ( p = 0.006). Verity et al. highlighted the significant impact of stigma on health-related quality of life and depression ( p = 0.01), underscoring the complex interplay between stigma, self-compassion, mental health, and quality of life in individuals with PD. Section title: Theme five: beyond stigma Educational score: 1.815429449081421 Domain: biomedical Document type: Other Language: en While the stigma surrounding PD is undeniable, it is essential to recognise that not all attitudes towards PD are negative. In this fifth and final theme, the nuanced aspects of the PD experience beyond stigma are explored, highlighting positive interactions, resilience, and advocacy efforts among individuals living with the condition. Section title: Positive interactions and support Educational score: 2.327409505844116 Domain: biomedical Document type: Study Language: en Despite the pervasive stigma surrounding PD, individuals often encountered positive interactions and support from their social networks and communities. Chiong-Rivero highlighted instances where individuals received assistance and empathy from strangers in public settings, challenging preconceived notions of stigma. For example, one participant described how bystanders on a bus rushed to help after she tripped, illustrating compassion and support from unexpected sources . Similarly, Fothergill-Misbah noted that despite the challenges of stigma, individuals with PD often found solace and support in peer-led support groups. These groups were felt to serve as safe spaces where the individual could share their experiences without fear of judgment, which fostered a sense of community and understanding for them. Section title: Resilience and advocacy efforts Educational score: 2.005664587020874 Domain: biomedical Document type: Other Language: en Stigma was also reported to catalyse resilience and advocacy efforts among individuals with PD. Despite facing discrimination and misunderstanding, some participants in Fothergill-Misbah expressed a desire to educate their communities and raise awareness about PD. Additionally, Hermanns highlighted the capacity of individuals to accept themselves for who they were, embracing their identity as people living with PD. This self-acceptance represented a powerful form of resilience in the face of societal stigma and discrimination. Section title: Discussion Educational score: 3.3755996227264404 Domain: biomedical Document type: Review Language: en Research addressing the stigma faced by individuals with PD in various social contexts and cultural settings is relatively recent. Of the 22 studies included in the review, 17 were conducted in the last decade, suggesting an increasing focus on this issue. The findings reveal significant public stigma towards individuals with PD across various global contexts, including Tanzania, Jordan, the United States of America (USA), and the United Kingdom (UK). This widespread stigma demonstrates its universal nature, transcending cultural and socioeconomic boundaries. Understanding this global perspective is crucial for developing comprehensive strategies to address the pervasive impact of stigma. This has been demonstrated in one study who found raising awareness in various global contexts can combat stigma associated with COVID-19. Section title: Discussion Educational score: 3.947174549102783 Domain: biomedical Document type: Review Language: en One key aspect of the review highlighted by the inclusion of various countries is the diverse cultural beliefs and alternative explanations for PD which majorly contributes to stigma. Multiple studies highlighted that PD is often misattributed to aging, clumsiness, or supernatural causes. These misconceptions lead to shame, embarrassment, and reluctance to disclose the diagnosis, further exacerbating stigma. This includes the belief that causes such as nature spirits, poverty, personal hygiene, and violation of social taboos. Such beliefs, common in indigenous communities, may influence health-seeking decisions where individuals may prioritise traditional healing practices, which reflect deeply valued cultural perspectives on health, before considering medical care . This has been seen in other diseases such as cancer, where seeing healers may potentially affect timing of diagnosis and treatment in indigenous communities . Section title: Discussion Educational score: 1.7704622745513916 Domain: biomedical Document type: Other Language: en Additionally, these cultural beliefs and fears greatly influence public perception and treatment of individuals with PD. This is similar to other diseases like dementia, where in some cultures witchcraft, bewitchment and evil spirit possession are seen as causes of the disease and can lead to stigma . Section title: Discussion Educational score: 3.9419496059417725 Domain: biomedical Document type: Study Language: en A significant manifestation of PD stigma is the stereotype that it exclusively affects older individuals. This belief can lead to younger individuals feeling profound shame about their diagnosis, causing them to hide their condition and avoid seeking necessary support and resources . The age-related stereotype also affects healthcare professionals, who may attribute PD symptoms to aging rather than recognising them as disease manifestations. Such assumptions by healthcare providers perpetuate stigma and contribute to the mismanagement of the disease, negatively impacting patients’ health outcomes and quality of life. This attribution of disease to older age is also common in Multiple Sclerosis (MS), as one study found younger individuals living with MS encountered more stigma which indicates that disease stigma affecting younger individuals is prevalent across various conditions. Section title: Discussion Educational score: 3.9862213134765625 Domain: biomedical Document type: Review Language: en A primary physical manifestation of PD stigma is the public’s tendency to focus on visible symptoms, such as tremors, while neglecting non-visible aspects like cognitive impairment and mood disorders . This narrow perception reduces the disease to its apparent features, leading to inadequate support and heightened emotional burdens for individuals with PD and their caregivers. Motor symptoms and difficulties with activities of daily living (ADLs) contribute significantly to public stigma, particularly for those with noticeable impairments like lack of facial expression . This stigma can exacerbate motor symptoms through increased psychological stress and social isolation, further burdening caregivers . Similarly, people living with MS frequently experience significant stigma due to the visible symptoms of the disease, as evidenced by two studies, highlighting the impact on their quality of life . Section title: Discussion Educational score: 3.383478879928589 Domain: biomedical Document type: Other Language: en Stigma also profoundly impacts the mental health of individuals with PD, causing feelings of shame, embarrassment, social withdrawal, and worsened mental health . This is similar across multiple conditions including dementia , cancer and MS , causing low self-esteem, isolation and poor mental health in these conditions. This can have detrimental impacts on the well-being of individuals and their caregivers, who face significant emotional and psychological stress due to the demanding nature of living with disease and caregiving in a stigmatised context . Section title: Discussion Educational score: 3.28991436958313 Domain: biomedical Document type: Review Language: en Stigma in the workplace was a common theme in this review, leading to a reluctance in disclosing the condition, resulting in diminished self-confidence, loneliness, and depression . This can severely impact careers and finances, creating additional stress for caregivers . This is also prevalent in other diseases like MS, where one study found 79.2% of people with MS have experienced workplace stigma . This resulted in people feeling greater stress, low self-esteem and lower QoL. Section title: Discussion Educational score: 3.922208547592163 Domain: biomedical Document type: Review Language: en The review has shown how stigma increases with the duration and severity of PD. Eccles et al. noted higher levels of stigma among individuals with longer disease durations. Additionally, Ma et al. found that as PD progresses, so does the stigma, particularly due to visible symptoms such as tremors, balance difficulties, and wheelchair use. These symptoms lead the public to focus on motor impairments, neglecting broader impacts like cognitive impairment and mood disorders. This is similar in other illnesses like cancer, where time since diagnosis and disease severity have shown to have a positive effect on stigma experienced by the public . This narrow perception is problematic as it fosters a one-dimensional view of PD, marginalising those affected. Section title: Discussion Educational score: 3.8053295612335205 Domain: biomedical Document type: Study Language: en A significant factor in PD stigma is the lack of public education and awareness. Multiple studies [ 19 , 29 , 34 , 42 – 44 ] emphasised that poor understanding of PD reinforces stereotypes, hinders early diagnosis and treatment, and leads to social withdrawal and mental health issues. A well-informed public can better understand the full spectrum of PD, including both its visible and non-visible symptoms. By dispelling myths and correcting misconceptions, education can reduce the stigma associated with PD . This has been demonstrated in a study by Jagota et al. , where a public social media educational campaign showing videos of people with Parkinson’s disease had a positive impact in creating awareness about PD. Section title: Discussion Educational score: 1.9252724647521973 Domain: biomedical Document type: Study Language: en Poor media representation also impacts PD stigma. One study noted that media coverage often focuses on advanced-stage symptoms, creating a skewed and frightening image of PD. This reinforces stereotypes and stigma, as seen when a BBC drama inaccurately described PD as a ‘terminal condition,’ leading to complaints from viewers . Section title: Discussion Educational score: 1.4702672958374023 Domain: other Document type: Other Language: en Furthermore, the lack of comprehensive media representation means that the diverse experiences of those with PD are not adequately portrayed. The media’s depiction of PD is often limited to high-profile cases like Michael J. Fox, who serves as a spokesperson for the disease. While his advocacy is vital, it also highlights the scarcity of broader representation, which is necessary for a nuanced public understanding of PD. Section title: Discussion Educational score: 1.397656798362732 Domain: other Document type: Other Language: en This inaccurate media representation creates a distorted and negative public perception . This skewed portrayal reinforces stereotypes, heightening public fear and misunderstanding about PD. As a result, individuals with PD may find it challenging to integrate into society and receive empathy and support. Section title: Discussion Educational score: 1.8783375024795532 Domain: biomedical Document type: Other Language: en This negative image of disease portrayed by the media has also been seen in dementia. One study discussed common frames of the disease used by the media, including being ‘old’, being a burden of care, and the ‘living dead’ frame, where common descriptions include ‘death before death’. This intense media scaremongering approach can lead to social stigmatisation and create a social distance between those with dementia and those without. Section title: Discussion Educational score: 3.6344234943389893 Domain: biomedical Document type: Study Language: en Comprehensive awareness campaigns, such as those used within the aforementioned study , using various media platforms can disseminate accurate information about PD. Additionally, integrating PD education into school curricula and workplace training programs can normalise discussions about the disease and encourage inclusivity. These programmes can equip young people and professionals with the knowledge to support peers and colleagues with PD and have proven to be successful in previous research where education in schools has positively changed students’ knowledge about and attitudes towards dementia [ 72 – 74 ]. Utilising the influence of public figures such as Michael J Fox and ensuring accurate media portrayals can also help shift perceptions, presenting balanced views of PD across various stages and backgrounds. By addressing these factors, it is possible to reduce stigma and improve the overall well-being of those living with PD. Section title: Discussion Educational score: 2.1751315593719482 Domain: biomedical Document type: Other Language: en These targeted interventions mentioned could help mitigate cultural beliefs surrounding PD. For instance, awareness campaigns aimed at disseminating accurate information are essential, particularly in indigenous communities where individuals may avoid medical care and turn to traditional healers. By providing reliable information, these campaigns can challenge misconceptions, such as the belief that PD is caused by witchcraft, thereby reducing cultural stigma and encouraging earlier medical intervention. Section title: Strengths and limitations Educational score: 4.025994300842285 Domain: biomedical Document type: Review Language: en A key strength of this systematic review is that, to our knowledge, it is the first to comprehensively explore the stigma experienced by individuals affected by Parkinson’s disease. The review used an extensive search strategy, covering a wide array of databases, including Google Scholar and reference lists, combined with broad search terms and well-defined inclusion and exclusion criteria. This approach maximised the capture of relevant studies to address the research question. However, a notable limitation is the restriction to English-language publications, which may have excluded valuable insights on stigma from non-English-speaking regions, potentially limiting the understanding of stigma experiences across different cultural contexts. Section title: Implications Educational score: 3.7903172969818115 Domain: biomedical Document type: Review Language: en This review highlights implications for policymakers, clinicians, and researchers. Policymakers should prioritise public awareness campaigns to correct misconceptions about PD and reduce cultural and age-related stigma. Clinicians should adopt a holistic, culturally sensitive approach that addresses both the physical and psychological effects of stigma in PD, offering support for mental well-being alongside medical treatment. Future research should focus on how cultural beliefs shape stigma, as well as on the resilience and advocacy demonstrated by those living with PD, to inform more empowering and inclusive healthcare strategies. Section title: Conclusion Educational score: 4.018975734710693 Domain: biomedical Document type: Review Language: en This systematic review examined the multifaceted nature and far-reaching impacts of stigma surrounding PD. The review synthesised findings from diverse studies, and revealed that stigma manifests through negative stereotypes, misconceptions, social exclusion, and discrimination, affecting both individuals with PD and their caregivers. The underlying drivers include lack of awareness, cultural beliefs, and societal norms, which perpetuate misconceptions and hinder access to essential resources and support. The consequences are profound, leading to social isolation, reduced quality of life, and psychological distress, as well as challenges in employment, financial stability, and healthcare access. However, the review also highlighted resilience, advocacy, and positive interactions, underscoring the agency and strength of individuals with PD. These insights highlight the need for targeted education, awareness campaigns, and advocacy initiatives. Future research should focus on longitudinal studies assessing the effectiveness of stigma-reduction interventions and explore how cultural and societal factors influence stigma. Such studies could fill gaps in the current literature and provide evidence-based strategies to improve the well-being of individuals with PD and their caregivers. Section title: Electronic supplementary material Educational score: 0.9769887328147888 Domain: other Document type: Other Language: en Below is the link to the electronic supplementary material. Section title: Electronic supplementary material Educational score: 1.2997463941574097 Domain: biomedical Document type: Other Language: en Supplementary Material 1 Section title: Electronic supplementary material Educational score: 1.2816039323806763 Domain: biomedical Document type: Other Language: en Supplementary Material 2 Section title: Electronic supplementary material Educational score: 1.2654812335968018 Domain: biomedical Document type: Other Language: en Supplementary Material 3 Section title: Electronic supplementary material Educational score: 1.2187254428863525 Domain: biomedical Document type: Other Language: en Supplementary Material 4 Section title: Electronic supplementary material Educational score: 1.2293976545333862 Domain: biomedical Document type: Other Language: en Supplementary Material 5 | Review | biomedical | en | 0.999995 |
PMC11697968 | Section title: Background Educational score: 3.9168388843536377 Domain: biomedical Document type: Review Language: en Chronic hypertension among women of reproductive age is an important risk factor of hypertensive disorders of pregnancy, a leading cause of pregnancy-related mortality in the United States (US) [ 1 – 4 ]. Rates of perinatal mortality are significantly higher among pregnant women with chronic hypertension than those with normotensive pregnancies , and women who suffer hypertensive disorders of pregnancy have substantially higher risks of cardiovascular disease later in life . Rates of chronic and gestational hypertension are increasing in the US, due in part to increased prevalence of obesity and higher average maternal age . Consequently, there is growing awareness of the need for effective prevention and control of hypertension among women of reproductive age to improve women’s cardiovascular and maternal health outcomes . Section title: Background Educational score: 3.5587985515594482 Domain: biomedical Document type: Review Language: en There are important demographic disparities in chronic hypertension risk among women across the US. Non-Hispanic Black and American Indian/Alaskan Native women are substantially more likely to develop chronic hypertension than White women , and women residing in rural areas are more likely to develop chronic hypertension than those living in urban environments . Sociodemographic factors represent additional disparities in hypertension prevalence, as women with lower income and education levels tend to have higher prevalence of hypertension than those with higher socioeconomic metrics . Efforts to address these disparities are necessary to mitigate increasing rates of hypertension in the US . Section title: Background Educational score: 4.06799840927124 Domain: biomedical Document type: Study Language: en North Dakota has large rural and substantial minority populations with severe disparities in health outcomes and healthcare access, which may contribute to disparities in hypertension awareness, prevention, and control [ 11 – 13 ]. Thirty-eight of the 53 North Dakota counties are designated by the Health Resources and Services Administration as primary care health professional shortage areas (HPSAs) . Residents of HPSAs have lower access to medical care, including outpatient and preventive care, than people living in non-shortage areas . North Dakota also has substantial minority populations. Non-Hispanic American Indians are the most abundant minority ethnic/racial group, comprising more than 5% of the overall population . The American Indian population in North Dakota faces severe disparities in general health status and adverse pregnancy outcomes relative to the general population, including higher infant mortality rates, lower access to satisfactory prenatal care, higher rates of gestational diabetes, and higher rates of adverse childhood experiences [ 20 – 24 ]. In the northern Great Plains region, which includes North Dakota, American Indian health outcomes tend to be substantially worse than among American Indian populations in the US overall, indicating that these racial disparities are heightened by conditions associated with this region . Section title: Background Educational score: 3.214351177215576 Domain: biomedical Document type: Study Language: en There have been limited studies of disparities and predictors of chronic hypertension in North Dakota, especially among women of reproductive age. Therefore, the objectives of this study were to investigate predictors of self-reported chronic hypertension among women of reproductive age. The results of this study can be used to guide efforts to control pre-pregnancy hypertension and reduce the burden of hypertensive disorders among women of reproductive age in North Dakota. Section title: Ethics approval Educational score: 1.0980969667434692 Domain: other Document type: Other Language: en This study was reviewed by the University of Tennessee Institutional Review Board and determined to be eligible for exempt review under 45 CFR 46.101. Anonymized secondary data were provided to researchers without identifiers. Study subjects were not re-identified or contacted by the investigators. All relevant guidelines and regulations were adhered to during the investigation. Section title: Study area and data source Educational score: 1.9166853427886963 Domain: biomedical Document type: Study Language: en This study was conducted in North Dakota, a state with 53 counties and a population of approximately 773,000 people. The state’s population is predominately non-Hispanic White (83%), followed by non-Hispanic American Indian (5%), Hispanic or Latino (4%), and non-Hispanic Black (3%). All other races or combinations of races comprise approximately 5% of the population. Women of reproductive age (18–44 years) comprise 18% of the total population . Section title: Study area and data source Educational score: 2.4201560020446777 Domain: biomedical Document type: Study Language: en Behavioral Risk Factor Surveillance System (BRFSS) data from the years 2017, 2019, and 2021 were obtained from the North Dakota Department of Health and Human Services (NDDHHS). The BRFSS is a telephone-based survey of health-related behaviors, chronic health conditions, and usage of medical services. The survey questionnaire is administered annually by the NDDHHS in partnership with the Centers for Disease Control and Prevention (CDC). Eligible participants include noninstitutionalized females of reproductive age (18–44 years). Questions relating to high blood pressure are administered on a bi-annual basis , so data on hypertension were not available in the 2018 or 2020 BRFSS data. Section title: Study population Educational score: 3.1415860652923584 Domain: biomedical Document type: Study Language: en The study population was women of reproductive age (18–44 years old) who responded to the question “Have you ever been told by a doctor, nurse, or other health professional that you have high blood pressure?”. Respondents who answered “Yes” were provided the follow-up question: “Was this only when you were pregnant?” Respondents who were never told they had high blood pressure, had borderline high blood pressure, or were only told they had high blood pressure during pregnancy were categorized as non-hypertensive. Those who said that they had been told they had high blood pressure were categorized as having hypertension. Section title: Selection of potential predictors Educational score: 4.177753448486328 Domain: biomedical Document type: Study Language: en A conceptual causal model was developed based on biological knowledge and questions asked in the BRFSS survey . The variables that were considered as potential predictors of hypertension are listed in Table 1 and consist of a variety of demographic factors, behavioral risk factors, chronic conditions, and variables associated with healthcare access and utilization including: age, race/ethnicity, smoking status, binge drinking, physical activity, fruit and vegetable consumption, frequent mental distress, body mass index (BMI), residence in an HPSA, inhibitive medical costs, personal healthcare provider, time of most recent checkup, and health insurance. Fig. 1 Conceptual model of predictors of hypertension among women aged 18–44 years in North Dakota Table 1 Demographic factors, lifestyle characteristics, and chronic health status of women aged 18–44 years in North Dakota, 2017–2021 Category Characteristic Weighted Frequency (standard error) Percent Hypertension (95% Confidence Level) Demographics Age 18–34 91,876 (3,138) 2.4 (2.4, 5.0) 35–44 44,753 (1,750) 6.9 (6.9, 11.6) Race White 107,025 (3,021) 5.1 (3.9, 6.2) American Indian 7,314 (788) 8.9 (3.1, 14.7) Black 6,042 (951) 6.7 (0, 13.6) Other Race/Ethnicity 15,912 (1,462) 11.9 (5.7, 18.1) Behaviors Heavy Drinking > 7 drinks per week 10,268 (1,045) 4.4 (0, 9.8) ≤ 7 drinks per week 119,186 (3,290) 5.8 (4.5, 7.0) Smoking Status Current smoker 22,193 (1,518) 8.9 (5.6, 12.2) Non-smoker 110,211 (3,170) 4.9 (3.6, 6.2) Physical Activity Outside of Current Job in Last Month No physical activity 33,036 (1,850) 7.1 (4.2, 10.0) Some physical activity 99,177 (3,016) 4.9 (3.6, 6.2) Fruit and Vegetable Consumption < 5 per day 103,458 (3,083) 5.8 (4.4, 7.1) ≥ 5 per day 22,363 (1,490) 5.6 (2.3, 8.9) Chronic Conditions Frequent Mental Distress (FMD) ≥ 14 poor mental health days 27,505 (1,791) 8.0 (4.5, 11.6) < 14 poor mental health days 107,976 (3,081) 4.6 (3.5, 5.8) Unimputed Body Mass Index (BMI) Obese (BMI ≥ 30) 37,376 (1,875) 10.2 (7.2, 13.3) Overweight (25 < BMI ≤ 29) 31,441 (1,763) 4.5 (2.1, 6.9) Normal (18.5 < BMI ≤ 25) 49,988 (2,251) 3.0 (1.7, 4.4) Underweight (BMI ≤ 18.5) 2,555 (531) 0.6 (0, 1.6) Unknown/Missing 15,269 (1,204) 10.1 (5.2, 15.1) Imputed BMI Obese (BMI ≥ 30) 41,229 (1,916) 14.3 (11.1, 17.6) Overweight (25 < BMI ≤ 29) 34,388 (1,802) 8.6 (5.5, 11.7) Normal (18.5 < BMI ≤ 25) 55,046 (2,301) 4.8 (3.2, 6.4) Underweight (BMI ≤ 18.5) 2,736 (534) 0.5 (0, 1.5) Healthcare Access/Utilization Problems with Medical Cost in Last 12 Months Could not afford needed care 59,589 (2,325) 3.0 (1.6, 4.4) Afforded all needed care 76,672 (2,662) 7.4 (5.6, 9.2) Personal Doctor No personal doctor 27,940 (1,826) 6.2 (3.0, 9.5) Has personal doctor 108,445 (3,058) 5.4 (4.1, 6.6) Most Recent Checkup Longer than 1 year ago 43,216 (2,074) 4.3 (1.8, 6.7) Within last year (reference) 89,890 (2,887) 5.8 (4.5, 7.2) Healthcare Insurance No healthcare insurance 11,192 (1,105) 6.9 (2.2, 11.7) Has healthcare insurance 112,371 (3,329) 9.1 (7.8, 10.6) Primary Care Health Professionals Shortage Area (HPSA) Score Resides in HPSA 44,428 (1,884) 11.5 (8.9, 14.1) Does not reside in HPSA 92,202 (3,054) 7.7 (5.8, 9.5) Section title: Re-coding of variables Educational score: 3.8606770038604736 Domain: biomedical Document type: Study Language: en All data cleaning and analysis were conducted using SAS Version 9.4 . Age was categorized into a binary variable of ages 18–34 and 35–44 years, corresponding with evidence that pregnancy-related morbidity and mortality is significantly higher in women ages 35 years and older . Race and ethnicity were categorized as non-Hispanic white, American Indian, non-Hispanic Black, or Other Race/Ethnicity. Frequent mental distress (FMD) was calculated based on respondents’ answer to the question “how many days during the past 30 days was your mental health not good?”, using the CDC definition of 14 or more bad mental health days to define FMD . Body mass index was calculated and categorized by CDC based on the height and weight of the respondent (BMI under 18.5 = underweight; between 18.5–24.9 = normal weight; 25.0–29.9 = overweight; 30.0 or greater = obese). Time of most recent checkup was categorized as having had a checkup within the last year or having a checkup more than one year ago. Residence in a primary care HPSA was dichotomized based on the primary care HPSA score of the county where the respondent resided, with any score > 0 being categorized as living in an HPSA. All other predictors were dichotomous, e.g., whether the respondent was a current smoker (yes/no), whether the respondent was a heavy drinker (yes/no). Section title: Imputation Educational score: 4.176929473876953 Domain: biomedical Document type: Study Language: en The percentage of missing data was investigated for each potential predictor variable. For any predictor with more than 5% missing data in the target population, the missingness was analyzed in relation to other predictor variables and the outcome variable using univariable logistic regression. BMI had 5.5% missing data and so was a candidate for imputation. If there was evidence of an association between a predictor’s missing data and the outcome or other predictor variables, the data were considered not missing completely at random. Responses that were not missing completely at random were imputed using the surveyimpute procedure in SAS using the hot-deck method with weighted selection . Imputation cells included covariates that were expected to be associated with the predictor being imputed based on the causal model and that had a simple association with hypertension (Table 2 ). Five donor cells were provided for each imputed response, and sampling weights for imputed values were divided by the number of donor cells. The imputation was implemented on the entire dataset, including males and people older than 18–44 years old. Table 2 Results of univariable binary logistic regression models investigating simple associations between hypertension and potential predictors among women aged 18–44 years in North Dakota, 2017–2021 Predictor Odds Ratio (95% Confidence Interval) p -value Age < 0.001 35–44 2.3 (1.6, 3.3) < 0.001 18–34 reference Race < 0.001 White 2.5 (1.4, 4.5) 0.001 American Indian 1.7 (0.6, 4.6) 0.3 Black 1.6 (0.9, 3.0) 0.1 Other Race/Ethnicity reference Heavy Drinking 0.2 > 7 drinks per week 0.7 (0.2, 1.9) 0.46 ≤ 7 drinks per week Smoking Status < 0.001 Current smoker 2.0 (1.3, 3.1) 0.002 Non-smoker reference Physical Activity Outside of Current Job in Last Month < 0.001 No physical activity 1.7 (1.1, 2.6) 0.01 Some physical activity reference Fruit and Vegetable Consumption 0.9 < 5 times per day 1.0 (0.6, 1.7) 0.9 ≥ 5 or more times per day reference Frequent Mental Distress < 0.001 ≥ 14 poor mental health days 2.2 (1.4, 3.4) < 0.001 < 14 poor mental health days reference Body Mass Index (BMI) < 0.001 Obese (BMI ≥ 30) 3.3 (2.2, 5.1) 0.005 Overweight (25 < BMI ≤ 29) 1.9 (1.1, 3.1) 0.01 Normal (18.5 < BMI ≤ 25) 0.1 (0.01, 0.8) 0.005 Underweight (BMI ≤ 18.5) reference Problems with Medical Cost in Last 12 Months 0.004 Could not afford needed care 1.7 (1.0, 2.8) 0.03 Afforded all needed care reference Personal Doctor < 0.001 No personal doctor 1.8 (1.1, 3.0) 0.03 Has personal doctor reference Most Recent Checkup < 0.001 Longer than 1 year ago 0.5 (0.3, 0.8) 0.005 Within last year (reference) reference Healthcare Insurance 0.3 No healthcare insurance 1.3 (0.6, 2.9) 0.5 Has healthcare insurance reference Primary Care Health Professionals Shortage Area (HPSA) < 0.001 Resides in HPSA 1.6 (1.1, 2.3) 0.01 Does not reside in HPSA reference Section title: Descriptive analyses Educational score: 4.029438018798828 Domain: biomedical Document type: Study Language: en Descriptive analyses were conducted using the surveyfreq procedure in SAS to account for the complex survey design of the BRFSS data . The sampling weight (_LLCPWT), strata (_STSTR), and cluster (_PSU) variables were specified in each analysis . The original sampling weights provided by the CDC were divided by three to account for aggregation of three years of surveys . Weighted frequencies and hypertension prevalence were calculated with standard errors and 95% confidence levels, respectively. The full BRFSS dataset was not filtered to the target population, but instead domain analyses were conducted by calculating stratified tables based on respondents’ sex and age to ensure accurate calculation of standard errors and confidence intervals of weighted estimates . Section title: Predictor investigation Educational score: 4.0544023513793945 Domain: biomedical Document type: Study Language: en Model building followed a two-step process. First, all potential predictors from the conceptual model were assessed for simple associations with hypertension in univariable logistic regression models. Predictors were retained for further analysis if the p -value of the likelihood ratio test comparing the univariable model to a null model was < 0.20 . All models accounted for complex survey designs by specifying the sampling weight, strata, and cluster variables using the surveylogistic procedure in SAS software version 9.4 . Section title: Predictor investigation Educational score: 4.07049036026001 Domain: biomedical Document type: Study Language: en The variables that had p < 0.20 in the 1st step were then assessed in a multivariable model using a manual backward selection process to identify a final parsimonious model. Covariates were removed from the model one-by-one based on p -values until all remaining variables were significant at a critical p -value of 0.05. At each step, the coefficients of remaining variables were compared before and after the removal of a covariate. If the coefficients changed by 20% or more, the variable being removed was considered a confounder and was retained in the model regardless of its statistical significance . The predictive ability of the final model was assessed using a receiver operating characteristic (ROC) curve and area under the curve (AUC) . Section title: Descriptive analysis results Educational score: 3.39005446434021 Domain: biomedical Document type: Study Language: en The weighted total number of women ages 18–44 years was 136,629 persons. Approximately 67% of the study population were aged 18–34 years, while the remaining 33% were aged 35–44 years. Most of the population was non-Hispanic white (78%), 5% was non-Hispanic American Indian, 4% was non-Hispanic black, and 13% were other races or ethnicities. Thirteen percent of the population were heavy drinkers, 16% were current smokers, 24% had no physical activity outside of work during the previous 30 days, 76% reported eating fruits or vegetables fewer than five times per day. Approximately 20% of the population reported frequent mental distress (FMD). After imputation of missing BMI data, most of the population was classified as either obese (33%) or overweight (25%). Approximately 43% of the population was unable to afford some needed medical care during the last 12 months, 20% had no personal healthcare provider, 32% did not have a healthcare checkup in the last 12 months, and 33% lived in a county designated as a primary care HPSA. Section title: Descriptive analysis results Educational score: 4.011499404907227 Domain: biomedical Document type: Study Language: en The overall prevalence of self-reported hypertension was 8.9% (95% CI = 7.4–10.4), but the prevalence varied widely across categories of some potential predictors. Notably, hypertension prevalence was disproportionately high among women who were American Indian or Other Race/Ethnicity (i.e., not white or black), current smokers, had no regular physical activity, had FMD, and were obese (Table 1 ). Of additional interest was that hypertension prevalence was lower among women who afforded all needed medical care in the last 12 months compared to women who could not afford some needed healthcare. Hypertension prevalence was also lower among those without a personal doctor compared to those with a personal doctor, and among women whose most recent healthcare checkup was more than 1 year ago compared to those who had a checkup within the last year (Table 1 ). Section title: Predictors of Hypertension Educational score: 3.9415206909179688 Domain: biomedical Document type: Study Language: en The following variables had significant univariable associations with hypertension, based on a critical p -value < 0.20, and were retained for assessment as potential predictors in the multivariable model: age, race, smoking status, physical activity, FMD, BMI, problems with medical costs, having a personal doctor, time of last recent checkup, and residence in a primary care HPSA (Table 2 ). Section title: Predictors of Hypertension Educational score: 4.137431621551514 Domain: biomedical Document type: Study Language: en Based on the final multivariable logistic regression model, significant ( p < 0.05) predictors of hypertension included age, FMD, BMI, time since last checkup, and residence in a primary care HSPA (Table 3 ). The odds of hypertension were higher among women who were aged 35–44 years, had FMD, were obese, and resided in a county designated as a primary care HPSA compared to women younger than 35 years, who did not have FMD, had a normal BMI, and did not reside in an HPSA, respectively. No confounders were identified. The AUC of the final model was 0.68. Table 3 Results of the final multivariable binary logistic regression model investigating predictors of hypertension among women aged 18–44 years in North Dakota, 2017–2021 Level Odds Ratio (95% Confidence Interval) p -value Age 35–44 2.3 (1.6, 3.4) < 0.001 18–34 reference Frequent Mental Distress ≥ 14 poor mental health days 2.0 (1.3, 3.3) 0.003 < 14 poor mental health days reference Body Mass Index (BMI) < 0.001 Obese (BMI ≥ 30) 2.6 (1.7, 4.1) < 0.001 Overweight (25 < BMI ≤ 29) 1.6 (1.0, 2.7) 0.08 Normal (18.5 < BMI ≤ 25) 0.1 (0.01, 0.8) 0.03 Underweight (BMI ≤ 18.5) reference Most Recent Checkup Longer than 1 year ago 0.6 (0.4, 0.9) 0.02 Within last year (reference) reference Primary Care Health Professional Shortage Area (HPSA) Resides in HPSA 1.8 (1.2, 2.6) 0.003 Does not reside in HPSA reference Section title: Discussion Educational score: 4.047142028808594 Domain: biomedical Document type: Study Language: en This study investigated predictors of self-reported hypertension risk among women of reproductive age in North Dakota using data from the 2017, 2019, and 2021 BRFSS and county-level HPSA designations. The results suggest that among women of reproductive age in North Dakota, those who lived in primary care HPSAs or had FMD had significantly higher odds of hypertension compared to their counterparts who did not live in HPSA or have FMD, respectively. Similarly, those who were obese or 35–44 years old had significantly higher odds of hypertension compared to those who were not obese or were 18–34 years old, respectively. The findings of this study are useful for understanding risk factors of chronic hypertension among women of reproductive age in North Dakota and can be used to guide the development and implementation of programs aimed at reducing hypertension in this population. Section title: Discussion Educational score: 4.089851379394531 Domain: biomedical Document type: Study Language: en The positive association between mental distress and hypertension is an important finding of this study. Self-reported mental distress is more prevalent among women and young adults than among men and older adults throughout the US, and the overall prevalence and disparities of FMD are increasing . Although mental health conditions, such as diagnosed depression, may have a direct biological association with the development of hypertension , the utility of self-reported mental distress in BRFSS data as a predictor of hypertension has not been adequately demonstrated. One study identified a univariable association between FMD and hypertension along with several other indicators of preconception health, but did not assess that association while controlling for other factors like BMI and age . However, there is evidence that FMD is associated with a variety of other health conditions, including diagnosed mental disorders, indicating that self-reported mental distress is associated with diagnosable mental and physical health problems . The results of this study indicate that among women of reproductive age in North Dakota, FMD is significantly associated with hypertension and may represent a modifiable risk factor. Section title: Discussion Educational score: 4.047844886779785 Domain: biomedical Document type: Study Language: en Although cardiovascular risk factor prevalence tends to be higher among people residing in HPSAs, there is some evidence that the association between HPSAs and cardiovascular disease risk factors is eliminated when controlling for underlying sociodemographic characteristics . Another study has reported that among uninsured populations, people residing in primary care HPSAs are less likely to achieve control of hypertension compared to those living in non-HPSAs . The present study shows that among North Dakota women aged 18–44 years, the effect of HPSA is robust to the control of risk factors related to demographics, behaviors, and healthcare access and utilization. Women who did not have a healthcare checkup in the last year were also less likely to report diagnosed hypertension, which might suggest lower detection and reporting rates of existing hypertension compared to women who had checkups in the last year. Section title: Discussion Educational score: 4.086098670959473 Domain: biomedical Document type: Study Language: en The associations between obesity, age, and hypertension are well documented [ 45 – 47 ]. Blood pressure naturally increases with age due to changes in arterial structure , and although women tend to have lower hypertension rates than men, blood pressure increases more rapidly in women after the age of 30 . It is important for women at later ages to reduce the risk of developing hypertension by engaging in behaviors that lessen the risk of developing hypertension or avoiding behavioral risk factors. Obesity is also an independent risk factor of hypertension, but obesity rates increase with age, compounding the increased age-associated cardiovascular health risks . Notably, women who were underweight in the present study had significantly lower odds of developing hypertension. This finding is consistent with those from other studies which reported that underweight was associated with lower risk of hypertension . However, there is evidence that underweight individuals have greater risk of cardiovascular disease than normal weight individuals, and one study reported that mortality rates among underweight people with severe hypertensions were significantly higher than among normal weight individuals . Section title: Discussion Educational score: 3.972184896469116 Domain: biomedical Document type: Study Language: en The unadjusted odds of hypertension were significantly higher among American Indian women than white women, but that effect was mediated by covariates in the multivariable model. This result is meaningful because of the health disparities that American Indian women in North Dakota face relative to the general population [ 20 – 24 ]. Based on this dataset, hypertension disparities among American Indian women of reproductive age are apparently mediated by some combination of demographic and behavioral risk factors, chronic conditions, and healthcare access or utilization. North Dakota public health officials should still consider racial disparities when designing programs to reduce hypertension in reproductive age women, but with the understanding that racial and ethnic disparities are mediated by other risk factors that were identified in this study. Section title: Study strengths and limitations Educational score: 4.073028564453125 Domain: biomedical Document type: Study Language: en This is the first study to use BRFSS data to investigate predictors of hypertension among women of reproductive age in North Dakota, and the results provide an improved understanding of risk factors of hypertension in this population that are useful for guiding efforts to improve cardiovascular and maternal health in this population. The study provides novel evidence of a robust association between self-reported FMD and hypertension and strengthens our understanding of associations between primary care HPSAs and chronic hypertension in North Dakota. These findings are useful for the North Dakota Department of Health and Human Services to guide the implementation of programs to raise awareness and improve control of hypertensive disorders to improve health and reduce the risk of adverse pregnancy outcomes among women of reproductive age. Section title: Study strengths and limitations Educational score: 4.0057830810546875 Domain: biomedical Document type: Study Language: en The use of BRFSS data means that hypertension classification was based on self-reporting and not direct measurement and hence the estimate of hypertension prevalence may be biased. Additionally, although FMD was a risk factor of hypertension in this study, that estimate of mental health is not specific to any condition. Finally, although HPSA was treated as a dichotomous variable in this study, the severity of primary care HPSAs are quantified by a numerical score that ranges from 0 to 25 . In this study HPSA was used as a dichotomous variable to be consistent with other studies . Taken together, these limitations probably contribute to the relatively low predictive power of the final model. Suffice it to say that this study provides initial findings to guide future studies and provides useful information to guide health program planning. Section title: Conclusions Educational score: 4.069402694702148 Domain: biomedical Document type: Study Language: en The odds of hypertension among women of reproductive age tend to be high among those with FMD, who reside in an HPSA, who are 35–44 years old, and who are obese. Women who did not have a checkup within the last year had lower odds of hypertension, probably indicating low detection and reporting rates in this segment of the population. These findings suggest that self-reported mental distress is a useful predictor of hypertension in this population, and further investigations should be conducted to determine whether reducing mental distress can reduce hypertension risk. The fact that high odds of hypertension were observed in HPSAs is important in guiding policy and public health service provision. Allocation of resources for public health programs intended to reduce chronic hypertension among women of reproductive age may need to prioritize HPSAs to reduce/eliminate these disparities and improve hypertension outcomes for all. | Review | biomedical | en | 0.999997 |
PMC11697977 | Section title: I. INTRODUCTION Educational score: 2.1706185340881348 Domain: biomedical Document type: Other Language: en From 2015 to 2021 there were only 11 biosimilars marketed in the US. In contrast, from 2008 to 2021, there were 55 biosimilars marketed in in the European Union. 1 This disappointing US output occurred despite the $261 billion in revenues that biologics generated in 2021, which comprised 46 per cent of all US drug spending. 2 Although biosimilar approvals have recently increased in the US, delayed entry persists. Biosimilars have the potential to drive these costs down with projected savings created by biosimilars to exceed $180 billion over the next five years. 3 Accordingly, Congress should promote strategies to expedite biosimilar market entry, while balancing the brand biologic’s need to recuperate costs and make enough profits to incentivize new drug innovation. Section title: I. INTRODUCTION Educational score: 2.0505805015563965 Domain: biomedical Document type: Other Language: en Biosimilar firms (hereinafter ‘biosimilars’) may not enter the market when there are relevant, valid patents covering the drug, regardless of the quality of those patents. Patents can cover the active ingredient (primary patents) or follow-on innovation (secondary patents), such as methods of use, methods of manufacture, formulation, route of administration, and sometimes even the devices used to administer the drug. Section title: I. INTRODUCTION Educational score: 2.0170252323150635 Domain: other Document type: Other Language: en Primary patents typically are the strongest patents and are the most difficult to invalidate or design-around. 4 Typically, generic drugs and biosimilars must wait until the primary patents expire before market entry. By contrast, secondary patents can extend monopoly rights long after the primary patents expire, but still must be challenged and revoked before biosimilars can enter the market free from risk. Secondary patents are invalidated at a higher rate and are generally considered weaker than primary patents. 5 For example, biosimilar firms that challenge the validity of biologic patents were successful in invalidating at least one claim in 70 per cent of all instituted America Invents Act-challenged patents, and most of these patents were secondary patents. 6 Without this type of ‘patent clearance’ the biosimilar risks an injunction that would prevent market entry or monetary damages owed to the patent owner. 7 Section title: I. INTRODUCTION Educational score: 1.8504263162612915 Domain: other Document type: Other Language: en Eliminating invalid patents is important because all relevant patents must be addressed before a biosimilar can enter the market without risk. Without patent pre-clearance, lower cost biosimilars may not enter the market in a timely fashion. One way to evaluate efficient biosimilar market entry is by examining the legal framework for challenging biologic patents, specifically litigation initiation under Biologic Price Competition and Innovation Act (BPCIA). Section title: I.A. Differences between Biosimilar and Small-Molecule Market Entry Requirements Educational score: 3.837556838989258 Domain: biomedical Document type: Other Language: en There are two broad categories of new drugs: small-molecule drugs and biologic drugs. Generic drugs are copies of branded small-molecule drugs while biosimilars are copies of branded biologic drugs. Small-molecule drugs are low-molecular weight products derived from chemical compounds, while biologics are high-molecular weight products produced by living cells in a bioreactor or fermenter. 8 Small-molecule drugs are chemically synthesized and are relatively easy and inexpensive to produce. By contrast, biologics are more complex in nature, and the methods of manufacture need to be tightly controlled to ensure consistent purity, potency and safety. Section title: I.A. Differences between Biosimilar and Small-Molecule Market Entry Requirements Educational score: 3.287853956222534 Domain: biomedical Document type: Other Language: en The cost of biosimilar development is much greater than generic drug development. Generic drug development typically costs $3 million and takes ⁓3 years. By contrast, the development of a biosimilar typically costs over $150 million and takes over 8 years. 9 , 10 Biosimilar development costs are greater in part because of the high price of the reference product (needed to be purchased for comparison studies at list price), the complex nature of manufacturing the biosimilar product, and conducting expensive clinical trials. Section title: I.A. Differences between Biosimilar and Small-Molecule Market Entry Requirements Educational score: 1.900942325592041 Domain: other Document type: Other Language: en Generic manufacturers do not need to conduct lengthy phase 3 clinical trials to obtain FDA approval for marketing because the small-molecule active ingredient is identical to the brand drug. Under the Hatch-Waxman Act, the patent litigation process starts when a generic firm files its Abbreviated New Drug Application (ANDA) with the FDA. 11 Because generic manufacturers do not have to engage in lengthy phase 3 trials, they often submit their ANDAs long before primary patent expires. 12 This allows the generic manufacturer to engage in patent litigation to clear secondary patents and complete the litigation process before the primary patent expires. By clearing a path through these secondary patents, generic manufacturers can launch their products close to the primary patent’s expiration date. 13 Section title: I.A. Differences between Biosimilar and Small-Molecule Market Entry Requirements Educational score: 3.1765999794006348 Domain: biomedical Document type: Other Language: en Biosimilar development cannot begin until after FDA approval of the brand biologic’s product, which the biosimilar firm must use as a reference product. This delay in development is created, in part, because the biosimilar firm requires samples of the reference product for analytical testing to determine the precise profile (for example, glycosylation profile, oxidation profile, etc.) of the drug to be copied. 14 These samples are not available until the brand biologic launches their product and makes it available for commercial purchase. Section title: I.A. Differences between Biosimilar and Small-Molecule Market Entry Requirements Educational score: 2.6499545574188232 Domain: biomedical Document type: Other Language: en Additionally, biosimilar firms must conduct costly and lengthy phase 3 trials to show that their products are similar in safety, purity and potency. The typical biosimilar phase 3 trial takes ⁓4.6 years to complete, and biosimilar firms cannot initiate litigation under the BPCIA until after phase 3 trials are completed 15 . The lengthy development programs of biosimilars leads to the litigation of secondary patents after expiration of the primary patent. This stands in contrast to generic drug patent clearance timelines, where secondary patent litigation occurs before the primary patent’s expiration date to allow for market entry quickly after the primary patent’s expiration date. Section title: I.B. The Current Biosimilar Litigation Framework Educational score: 1.3032244443893433 Domain: other Document type: Other Language: en A biosimilar firm has three options for entering the market. First, they could pre-clear the patents before entering the market by engaging in the ‘patent dance’ and associated patent litigations. A second option is to launch ‘at risk.’ Finally, biosimilar firms could settle with the brand biologic to avoid any active patents. Section title: I.B.1. The Patent Dance and Biosimilar Patent Litigation Educational score: 1.3601576089859009 Domain: other Document type: Other Language: en Biosimilar patent litigation is governed by the BPCIA which includes a pre-litigation process known the ‘patent dance’. 16 The patent dance is triggered when the biosimilar submits its FDA approval application and includes an exchange of information with the goal to provide clarity as to which patents may be relevant for litigation. 17 Section title: I.B.1. The Patent Dance and Biosimilar Patent Litigation Educational score: 1.3604501485824585 Domain: other Document type: Other Language: en Following the patent dance, the brand biologic then files a patent infringement complaint, asserting the patents listed by both parties in the patent dance. 18 The complaint initiates a traditional patent litigation procedure called ‘the first wave’ of litigation. The ‘second wave’ of litigation is triggered when the biosimilar firm gives 180 days’ notice to the brand biologic of its intent to begin commercial marketing. 19 Similar to the first wave of litigation, the second wave litigation cannot begin earlier than submission of the biosimilar application to the FDA. During the second wave litigation, the brand drug company is free to assert patents that the biosimilar firm did not agree to include during the patent dance. At this time, the branded drug company can also request a preliminary injunction to stop the biosimilar from manufacturing or selling its product. The purpose of requesting a preliminary injunction is to try to maintain the brand biologic’s market exclusivity until the completion of patent litigation. Section title: I.B.1. The Patent Dance and Biosimilar Patent Litigation Educational score: 1.3985795974731445 Domain: other Document type: Other Language: en Only after both waves of litigation are resolved, will the biosimilar firm know if it can launch its product free from patent risk. If litigated to final conclusion, firms have to engage in the first and second waves of litigation and the inevitable appeals associated with these litigations. Litigation can last for several years following FDA approval of the biosimilar, leading to delayed launch of the biosimilar long after the expiry of the primary patent. Section title: I.B.2. Launching At Risk/Settlement Educational score: 1.4904736280441284 Domain: other Document type: Other Language: en A biosimilar firm can launch ‘at risk’ which means it launches the biosimilar product while patent litigation is still ongoing. Launching at risk poses a significant threat to biosimilars because infringement findings could lead to ‘lost profit’ damages totaling hundreds of millions, well surpassing the anticipated earnings from the biosimilar product. This intimidating remedy imposes a difficult decision on biosimilar firms whose patent litigation is pending at the time they receive FDA approval for their product. Section title: I.B.2. Launching At Risk/Settlement Educational score: 1.4292527437210083 Domain: other Document type: Other Language: en Alternatively, the biosimilar may settle the patent litigation with the brand drug company and agree to a market entry date. We find that most biosimilar firms enter into settlements with the brand biologic to resolve the risk associated with potential patent infringement and oftentimes to reduce the delay associated with awaiting a final decision from the court on the litigation. Nevertheless, patent settlements usually involve launching with some delay after both FDA approval of the biosimilar and following expiry of the primary patent. Section title: II. SHIFTING LITIGATION FOR EXPEDITED BIOSIMILAR MARKET ENTRY Educational score: 1.6068814992904663 Domain: other Document type: Other Language: en One way to help biosimilars enter the market in a timely fashion, similar to generic drugs, is to allow patent litigation to start earlier. Specifically, biosimilars could be allowed to challenge patents at the beginning of the phase 3 clinical trials. Allowing biosimilars to bring suit earlier would help them enter the market when the primary patent expires, which would parallel the generic market entry process. Section title: II. SHIFTING LITIGATION FOR EXPEDITED BIOSIMILAR MARKET ENTRY Educational score: 1.7701410055160522 Domain: other Document type: Other Language: en There are several hurdles biosimilars may encounter if allowed to bring a lawsuit earlier in the biosimilar development process. First, the judicial ‘ripeness’ doctrine, may apply to prevent earlier initiation of the litigation process. Second, branded drug companies may consider that earlier litigation may be premature if the biosimilar product or manufacturing process is changed during or after phase 3 trials. Third, if the biosimilar does not succeed in completing phase 3 trials, then initiating the litigation process at an earlier point in time would have brought the brand firm into unnecessary, expensive litigation and waste court resources. Section title: II.A. Judicial Ripeness Educational score: 1.0612783432006836 Domain: other Document type: Other Language: en Before a court can take a case, the issues must be ‘ripe.’ A case is not ripe for adjudication if it rests upon contingent future events that may or may not occur. 20 In assessing ripeness, courts will consider ‘how far in the future the potential infringement is, whether the passage of time might eliminate or change any dispute and how much if any harm the potential infringer is experiencing, at the time of the lawsuit, that a litigation might redress.’ 21 Section title: II.A. Judicial Ripeness Educational score: 1.4443084001541138 Domain: other Document type: Other Language: en In Sandoz v. Amgen, the court was asked to assess the ripeness doctrine in a biosimilar patent litigation. Sandoz, the biosimilar firm, sought to challenge the validity of the patents with respect to their etanercept biosimilar. Because the BPCIA did not include a pathway for Sandoz to initiate a litigation prior to submitting their FDA approval application, Sandoz filed a declaratory judgment action three years prior to obtaining FDA approval. The district court concluded that the case was not ripe and no Article III controversy existed between the parties. The court reasoned that the BPCIA established the procedures for narrowing and resolving patent disputes between biosimilar and brand biologic firms and that Sandoz could not obtain a court judgment before filing an FDA application. 22 The Court of Appeals of the Federal Circuit (CAFC), the sole appellate court for patents, affirmed this decision. The CAFC concluded that a biosimilar firm ‘cannot engage in…liability-exposing conduct…without FDA approval of an application precisely defining the products it may market.’ 23 Section title: II.A. Judicial Ripeness Educational score: 1.267372488975525 Domain: other Document type: Other Language: en The court expressed concern that the phase 3 clinical studies might fail, potentially resulting in Sandoz not filing for FDA approval, thereby eliminating the patent dispute and wasting court resources. The court was also concerned that the biosimilar firm might have to modify its proposed product prior to submitting its FDA application, which might alter the list of patents in dispute. The court concluded that anything earlier than submission of the FDA application would be too premature to litigate because the case would not be ripe. Section title: II.A. Judicial Ripeness Educational score: 1.3802303075790405 Domain: other Document type: Other Language: en This case was decided in 2014, and at the time, no biosimilar had completed the FDA approval process. The CAFC admitted that ‘[t]he biosimilarity approval standard is new; indeed, the FDA has not yet applied the new standard to complete its review of and approve any product under the BPCIA…[and] [ p]erhaps the FDA is exercising a caution that will prove excessive over time. But we have no basis for saying so .’ 24 Section title: II.A. Judicial Ripeness Educational score: 2.1790196895599365 Domain: biomedical Document type: Other Language: en In light of a decade of additional biosimilar approvals, we find that the court’s concerns were unfounded. We find that pivotal phase 3 clinical studies require that the manufacturing process to be sufficiently fixed, preventing biosimilar firms from making significant changes to their product or manufacturing methods afterwards. Therefore, initiating litigation at the start of phase 3 trials would not be premature. Additionally, we find that most biosimilars that enter into phase 3 studies result in FDA-approved biosimilars. 25 Therefore, litigation at this stage will neither result in unnecessary litigation nor waste court resources. Section title: II.B. Litigation Would Not be Premature if Initiated at the Start of Phase 3 Clinical Studies Educational score: 3.9847066402435303 Domain: biomedical Document type: Study Language: en The process of manufacturing a biosimilar is crucial since the method of manufacture contributes the final biosimilar product profile. For example, the primary amino acid sequence, cell culture media and bioreactor conditions determine the ultimate physiochemical properties of a biosimilar product, including its glycosylation profile. Equally, steps used in the purification process of the biosimilar product influence its charge profile and purity profile. Section title: II.B. Litigation Would Not be Premature if Initiated at the Start of Phase 3 Clinical Studies Educational score: 3.846363067626953 Domain: biomedical Document type: Other Language: en Extensive process development and product characterization are required before entering phase 3 trials and are expected to be ‘locked’ before the drug is administered in human trials. This is because the FDA requires that the proposed biosimilar used in the phase 3 study be representative of the to-be-marketed biosimilar. 26 Changing the product or process after beginning the phase 3 clinical study is undesirable because biosimilar firms would likely need to generate extensive additional comparability data and/or additional clinical trials, adding significant delays and costs on their development program. 27 Therefore, biosimilar firms are already incentivized to avoid changing their product or process in a manner that could impact the patent dispute. Section title: II.C. Biosimilar Phase 3 Trials Are Unlikely to Fail so Litigation Should Not be a Waste of Court Resources Educational score: 2.3176381587982178 Domain: biomedical Document type: Other Language: en Brand drug companies may be concerned that, should the biosimilar not succeed in phase 3 trials, then initiating the litigation process at this time point would have brought the brand firm into unnecessary and expensive litigation. However, we find that a low percentage of biosimilars fail to obtain FDA approval following initiation of their phase 3 clinical study. This is largely because biosimilar phase 3 clinical trials are almost always confirmatory, meaning that the clinical study is unlikely to fail. Section title: II.C. Biosimilar Phase 3 Trials Are Unlikely to Fail so Litigation Should Not be a Waste of Court Resources Educational score: 3.9825189113616943 Domain: biomedical Document type: Other Language: en It is noteworthy that biosimilar phase 3 studies are far more likely to succeed as compared to branded biologic phase 3 studies. This is because brand biologics use phase 3 studies to demonstrate the risk and benefit of an untested drug candidate and large phase 3 trials that are required to show efficacy and safety. By contrast, the purpose of a biosimilar phase 3 trial is rather to compare the biosimilar to the brand biologic. By the time the biosimilar reaches the phase 3 trial stage, it has already undergone extensive evaluation and is advancing steadily towards obtaining FDA approval, hence the phase 3 study is merely confirmatory. Section title: II.C. Biosimilar Phase 3 Trials Are Unlikely to Fail so Litigation Should Not be a Waste of Court Resources Educational score: 2.137458086013794 Domain: biomedical Document type: Other Language: en Prior to the phase 3 study, the biosimilar firm is required to build a robust package of data including considerable, highly sensitive, analytical testing that compares the product profile of the biosimilar to the branded drug. All this information could be used by brand biologics to determine which product and process patents might be infringed. Section title: II.C. Biosimilar Phase 3 Trials Are Unlikely to Fail so Litigation Should Not be a Waste of Court Resources Educational score: 3.9733898639678955 Domain: biomedical Document type: Review Language: en Further evidence that biosimilar phase 3 studies are primarily confirmatory in nature comes from the regulatory field, where considerable debate exists over whether biosimilar clinical trials are even needed at all. 28 The Biosimilar User Fee Act III states that the FDA may waive and omit phase 3 studies for biosimilars. Similarly, the European Medicines Agency (EMA) is considering phase 3 study waivers. EMA-associated scientists reviewed all approved biosimilars and concluded that patient-trials did not play a decisive role in decision making. 29 Others argue that there is enough evidence from analytical, functional and pharmacokinetic studies to show biosimilarity. 30 The UK regulatory agency, already provides an option for biosimilars to waive phase 3 studies. These regulatory changes all suggest that biosimilar phase 3 studies are confirmatory in nature, meaning that biosimilar development can be considered more or less finalized once it reaches the stage of phase 3 clinical studies. Section title: II.C. Biosimilar Phase 3 Trials Are Unlikely to Fail so Litigation Should Not be a Waste of Court Resources Educational score: 2.4541635513305664 Domain: biomedical Document type: Study Language: en To investigate the obstacles associated with earlier litigation, we examined the failure rate of biosimilar approval beginning at the phase 3 trial stage. Additionally, we assessed the current timing of litigation to estimate potential time savings if litigation was initiated at an earlier stage. Section title: III.A. Patent Litigation Data Sources Educational score: 2.2070345878601074 Domain: other Document type: Study Language: en We used the Lex Machina litigation database to identify all patents involved in biosimilar litigation from January 1, 2010, the year that the biosimilars pathway was enacted, to December 31, 2022. The corresponding complaint date, district court termination date and CAFC termination date was identified for each biosimilar. 31 Lex Machina also classifies each litigation as: likely settled, open case, claimant win, or claim defendant win. For those cases that were litigated to final judgment, we reviewed the opinion to determine if the brand biologic or biosimilar firm ‘won’ the case. For cases that settled we used the court case dismissal date as the settlement execution date. A win for the brand biologic typically resulted in an injunction from making or using the product and could include monetary damages for lost profits. A win for the biosimilar typically resulted in either invalidation of the patent or a non-infringement decision. Section title: III.A. Patent Litigation Data Sources Educational score: 2.868802785873413 Domain: biomedical Document type: Study Language: en We assessed the timing of each patent litigation, when the litigation was initiated, the time taken to reach a first instance court decision, and a final decision on appeal. Appellate decisions from the CAFC were analyzed using Lex Machina. We used the median length of litigation as a unit for extrapolation (complaint to final judgment/dismissal). We also assessed the cases settled before a court decision was reached. We compared the timing of the patent litigation or settlement, as compared to when the biosimilar received FDA approval, the date of expiry of the primary patent, and the date of biosimilar launch. If the court prevented biosimilar entry until a specific injunction date, we used the injunction date as the predicted launch date. Section title: III.A. Patent Litigation Data Sources Educational score: 2.2303738594055176 Domain: biomedical Document type: Study Language: en For each litigated biosimilar we identified the: clinical trial ID, clinical trial start date, and clinical trial end date. 32 The biosimilars FDA approval application and FDA approval date were identified. 33 , 34 Section title: III.A. Patent Litigation Data Sources Educational score: 1.8968393802642822 Domain: biomedical Document type: Study Language: en For biosimilars that litigated to final judgment that resulted in a successful challenge (n = 5) or failed challenge (n = 3), we determined the median length of litigation (complaint date to appellate court final decision). For biosimilars that settled litigation (n = 24), we determined the median length of litigation (complaint date to district court dismissal date). Section title: III.A. Patent Litigation Data Sources Educational score: 1.6554864645004272 Domain: other Document type: Other Language: en For all litigated patents, we reviewed each patent 35 and determined if the patent was a primary patent, directed to the biologic’s active ingredient, or a secondary patent, directed to follow-on inventions (such as new formulations, methods of treatment, devices, etc). We calculated each patent’s expiration date and compared it against the settlement date or final court decision. Section title: III.B. Clinical Trial Data Sources Educational score: 3.4392991065979004 Domain: biomedical Document type: Study Language: en We used PharmaProjects 36 to collect data on biosimilar drugs (clinical and marketed) with phase 3 clinical trial studies conducted or partially conducted within the United States that measure biosimilarity with a brand biologic reference product. We collected the following data points: biosimilar name, reference product, and manufacturer. Rationales for phase 3 trial discontinuation were recorded. For example, if press releases stated that the trial was discontinued for commercial reasons or due to biosimilar bankruptcy. Section title: III.B. Clinical Trial Data Sources Educational score: 2.65299654006958 Domain: biomedical Document type: Study Language: en We subsequently used clinicaltrials.gov 37 to attain more specific phase 3 trial information, such as trial primary objectives. We took the earliest phase 3 trial and extracted: start date, end date, clinical trial number. We reviewed each clinical trial to determine if it was the pivotal trial relied upon by the FDA to grant biosimilar approval. Section title: III.B. Clinical Trial Data Sources Educational score: 4.037104606628418 Domain: biomedical Document type: Study Language: en The median time from phase 3 to FDA approval for all biosimilars that received FDA approval from January 1, 2010 to December 31, 2022 was 4.7 years (IQR 3.45–5.9). Accordingly, when assessing whether a biosimilar may have failed to obtain FDA approval, we excluded those biosimilars that were less than three years after initiation of phase 3 trials because those biosimilars were likely still undergoing development prior to FDA approval. Because the median time between the start of phase 3 to approval was 4.7 years, the median time from phase 3 to FDA approval is 4.7, to favor the counter-viewpoint, we classified as failures those phase 3 trials that were submitted before April 1, 2021 (more than 3 years) and lacked information on clinicaltrials.gov . Section title: III.B. Clinical Trial Data Sources Educational score: 2.499016761779785 Domain: biomedical Document type: Study Language: en For those biosimilars that completed a phase 3 trial, we included studies where the: (i) biosimilar launched and (ii) biosimilar engaged in patent litigation. We excluded those biosimilars that did not enter the market due to: (i) publicly declared commercial motivations, or (ii) if the clinical trials were likely still ongoing . Section title: III.C. Biosimilar Approval and Launch Data Sources Educational score: 1.6985734701156616 Domain: biomedical Document type: Other Language: en We used Drugs@FDA to extract biosimilar approval dates, biosimilar press releases, investor documents and Goodwin Procter LLP’s Big Molecule Watch to extract commercial launch dates of biosimilars. 38 Section title: IV.A. Phase 3 Clinical Trial Results Educational score: 3.8654778003692627 Domain: biomedical Document type: Study Language: en Among the 59 biosimilars that initiated phase 3 trials, 54 (92 per cent) resulted in enough information to begin litigation without wasting court resources. From 2010 to 2022, we identified 95 biosimilars associated with 25 brand biologics that reached the development stage of initiating phase 3 trials. When determining how many biosimilars may have failed to obtain FDA approval after initiating phase 3 studies, among the 95 biosimilars that started phase 3 trials, we included 59 and excluded 36. The reason we excluded 36 biosimilars: 29 (81 per cent) likely had ongoing clinical trials , 6 (17 per cent) publicly declared as discontinued for commercial reasons, and 1 (3 per cent) biosimilar bankruptcy . Section title: IV.A. Phase 3 Clinical Trial Results Educational score: 2.185150384902954 Domain: biomedical Document type: Other Language: en Among the remaining 59 biosimilars that initiated phase 3 trials, 36 (61 per cent) had launched in the US, 18 (31 per cent) were undergoing litigation, meaning they had submitted their aBLA application to the FDA, 1 (2 per cent) failed phase 3 trial, and 4 (7 per cent) provided no online information . Section title: IV.A. Phase 3 Clinical Trial Results Educational score: 2.75504994392395 Domain: biomedical Document type: Study Language: en We counted the four biosimilars for which there was no online information as failures, so as to bias the results towards the counter argument. In summary, among the 59 included biosimilars, 54 (92 per cent) went on to at least submit their dossier to the FDA, meaning court resources would not have been wasted if patent litigation had started at the initiation of phase 3 clinical trials. By contrast, only 1 (2 per cent) would have resulted in unnecessary litigation, with four additional cases (7 per cent) that could potentially result in unnecessary litigation costs and resources. Section title: IV.B. Litigation Results Educational score: 1.4463438987731934 Domain: other Document type: Other Language: en From 2010 to 2022, 32 biosimilars entered the market with completed judicial proceedings. Five (16 per cent) of the 32 litigated biosimilars won litigations against the brand biologic, with 4 litigations appealed to the CAFC [3 affirmed; 1 procedurally dismissed]. Only 3/32 (9 per cent) of biosimilars lost litigation, with 2 being appealed to the CAFC [2 affirmed]. The remaining 24/32 (75 per cent) biosimilars settled and none appealed to the CAFC (all settlements occurred at the district court level). Section title: IV.B. Litigation Results Educational score: 2.8025457859039307 Domain: biomedical Document type: Study Language: en The median duration for litigation (from the filing date of the complaint until a final court decision) is 2.9, 0.95 and 4.2 years, for biosimilar wins, settlements, and biosimilar losses, respectively ( Table 1 ). Biosimilar launch is delayed substantially following a litigation loss because a permanent injunction is typically granted until primary patent expiry. Biosimilar market entry occurs a median of 2.3, 3.2, or 16.5 years after the primary patent expiry when biosimilars win, settle or lose litigation, respectively. Biosimilar market entry occurs a median of 1.3, 1.8, 10.0 years after initiation of litigation when biosimilars win, settle, or lose litigation, respectively. Section title: IV.B. Litigation Results Educational score: 3.1820228099823 Domain: biomedical Document type: Study Language: en Most biosimilar patent cases are settled before a final judgment on the merits is reached. If a biosimilar settles the case, the litigation is resolved in 0.95 years after initiation of litigation. Following settlement, the biosimilar launch occurs a median of 1.8 years after initiation of the patent litigation. The median duration between the primary patent expiry and biosimilar launch is 2.3, 2.5, and 16.5 years when biosimilars win, settle or lose litigation. The median time between the start of phase 3 and primary patent expiration is 2.8, 3.0, −0.21 years when biosimilars win, settle, or lose. We note that when biosimilars lose litigation, they typically start their phase three trials after the primary patent expires. Therefore, we find that settlement allows biosimilars to enter the market earlier than if they had awaited the median duration of time for litigation to conclude (2.9 years or 4.2 years). Section title: IV.B. Litigation Results Educational score: 1.2247852087020874 Domain: other Document type: Other Language: en Allowing firms to initiate litigation at the start of phase 3 trials would allow firms to launch closer to the primary patent expiration date. For those firms with strong invalidity / non-infringement positions who litigate to final judgment, the appellate litigation would conclude about 1 month after the primary patent expires . For those firms who decide to settle, shifting the litigation start time would allow biosimilars to enter close to the primary patent expiration date because litigation would terminate before the primary patent expires . Section title: V. DISCUSSION Educational score: 2.0330729484558105 Domain: other Document type: Other Language: en When biosimilars win patent litigation or settle, market entry occurs ⁓2.5 years after the primary patent expires. This is in stark contrast to generic drug entry where market entry occurs close to the expiration of the primary patent. 39 By allowing biosimilar firms to start litigation at the start of phase 3 trials, they could litigate all relevant patents so that market entry occurs close to the expiration of the primary patent. Allowing biosimilar firms to litigate earlier will not be a waste of court resources because 91 per cent of all biosimilar firms who start phase 3 have sufficient information about their product and process to make the issue ripe for adjudication. Allowing biosimilar patent litigation to start upon initiation of phase 3 studies would provide more time to litigate the case prior to expiry of the primary patent, which would allow for earlier path clearing and may accelerate biosimilar entry. Section title: V. DISCUSSION Educational score: 1.472093939781189 Domain: other Document type: Other Language: en Starting biosimilar litigation earlier may result in reducing the number of cases that settle. Currently, 75 per cent of biosimilars settle their cases with the brand drug company. From the biosimilar’s perspective, settlement removes the risk of being ordered to pay damages to the brand or being removed from the market with an injunction, eg, if they are eventually found to infringe secondary patents. From the brand’s perspective, if their primary patent has already expired, they may be concerned that a biosimilar would launch even while secondary patents are still in force. The uncertainty on both sides exists so long as the litigation is pending. However, earlier initiation of litigation may allow the patent landscape to be clarified in time for the biosimilar’s typical target launch date: expiry of the primary patent. Section title: V. DISCUSSION Educational score: 2.8995792865753174 Domain: biomedical Document type: Study Language: en The median duration for litigation from the date the complaint was filed until a final court decision is 2.9 for biosimilar wins and 4.2 years for biosimilar losses. In comparison, the median time from phase 3 to FDA approval was 4.7 years (IQR 3.45–5.9). Therefore, we assume that almost all biosimilars would have sufficient time to complete their patent litigation before FDA approval if the litigation is initiated at the beginning of the phase 3 studies. Section title: V. DISCUSSION Educational score: 3.9594554901123047 Domain: biomedical Document type: Study Language: en We find that 92 per cent of biosimilars progress to submitting an application to the FDA after initiation of phase 3 study while only 8 per cent fail. Therefore, allowing earlier litigation would not result in wasted court resources. This aligns with the fact that biosimilar phase 3 studies are merely confirmatory in nature and a robust comparability data package is already complete by the time the biosimilar reaches this last stage in development. Furthermore, allowing litigation to begin at this earlier time point is unlikely to be premature. When a biosimilar initiates phase 3 clinical trials, they are incentivized to ensure that their product profile does not change in a way that would alter any patent dispute. Changing the product or process after starting the phase 3 clinical study is undesirable to the biosimilar firm because it would typically be required to produce extensive additional comparability data and/or additional clinical trials, which would add delay and cost to the biosimilar development program. Section title: V. DISCUSSION Educational score: 1.8135002851486206 Domain: other Document type: Other Language: en Biosimilars must weigh three options: (i) the possibility of winning litigation resulting in launching 2.3 years after primary patent expiry; (ii) settling with the brand biologic resulting in an end to litigation and a launch delay of 2.5 years after primary patent expiry; or (iii) the possibility losing litigation resulting in a 16.5-year delay after primary patent expiry plus large damage awards. We conclude that biosimilars are likely making rational decisions when entering settlement agreements that allow them to launch earlier than awaiting the end of litigation and exposing them to large damage awards. We postulate that the settlement rate for biosimilars is higher compared to generics because biosimilar firms do not have timely access to a final court decision on the follow-on patents prior to expiry of the primary patent. Section title: V. DISCUSSION Educational score: 2.7530672550201416 Domain: biomedical Document type: Study Language: en Several limitations of the present study require consideration. Because firms do not typically report failed clinical trials to clinicaltrials.gov , we may be overcounting failed trials because we include trials older than 3 years with no information as failed. We have also limited the phase 3 trials to those conducted and partially conducted in the United States. Although almost all of our data covers the key pivotal trials needed for biosimilar approval, there may be additional pivotal trials conducted in other countries. Finally, the BPCIA was enacted in 2010, and as a result, the quantity of biosimilars that have engaged in patent litigation and entered the market is limited. Section title: V.A. Possible Solution: Allow Biosimilars to Start BPCIA Litigation at the Start of Phase 3 Clinical Trials Educational score: 1.2963674068450928 Domain: other Document type: Other Language: en We suggest that Congress create a two-track litigation system. Track One would be identical to the current BPCIA system that is already in place. This would allow biosimilar firms who are uncomfortable with the new system or who do not wish to invest in patent litigation until closer to the point of FDA approval to use a litigation procedure that occurs at the end of the drug’s development process. For example, this track may be selected by those few biosimilars who would anyway have launched at risk. Importantly, this proposal would not affect those firms who decide not to engage in the patent dance. Section title: V.A. Possible Solution: Allow Biosimilars to Start BPCIA Litigation at the Start of Phase 3 Clinical Trials Educational score: 1.8301374912261963 Domain: other Document type: Other Language: en A second track, ‘Track Two,’ should be created to allow biosimilars to initiate patent litigation at the start of phase 3 trials. Track Two would shift the start of litigation from submission of the FDA approval application to the beginning of phase 3. Once the biosimilar enters this track, the biosimilar could bring a declaratory judgment action for invalidity and non-infringement of the branded patents and the patent owner could counter-sue. During the discovery part of litigation, the brand would have access to the biosimilars manufacturing process, product profile information and other confidential information, as per a traditional patent litigation. The brand would then include all potentially relevant patents into the lawsuit or be precluded from asserting them in future litigation. Similar to the 3A list of the BPCIA patent dance, following disclosure, no additional patents could be added to the litigation. Track Two would follow a traditional litigation process and would not include the patent dance, nor the first/second waves of litigation provided for under the BPCIA. The brand biologic, however, would be stopped from bringing later litigation based on patents not litigated unless the biosimilar manufacturing process or product profile changes to render additional patents relevant. Section title: V.A. Possible Solution: Allow Biosimilars to Start BPCIA Litigation at the Start of Phase 3 Clinical Trials Educational score: 1.668676733970642 Domain: other Document type: Other Language: en Like the current BPCIA framework, the biosimilar firm would have to provide the brand biologic with a copy of their FDA dossier as soon as it becomes available and provide a 180-day notice of commercial marketing, even if the Track Two litigation is already complete. This would allow the brand biologic a final check that the biosimilar product profile and manufacturing process have not changed since the initial litigation under Track Two. Additionally, biosimilar firms would have to place in escrow an amount of money to compensate brand biologics for litigation costs if the biosimilar fails phase 3 trials or if the product or process is changed enough to require additional patents to be litigated. Section title: V.A. Possible Solution: Allow Biosimilars to Start BPCIA Litigation at the Start of Phase 3 Clinical Trials Educational score: 1.335708498954773 Domain: other Document type: Other Language: en Of course, there is a risk that a brand would bring a superfluous second litigation based on a small tweak or no change at all in the biosimilar manufacturing process or product profile. Judicial discretion would be necessary to end such cases in summary judgment. Moreover, the biosimilar would more likely launch at risk during such a secondary litigation if the first litigation resolved the uncertainty surrounding patent validity and infringement. This pattern is observed with all biosimilars launching after a district court victory but preceding the CAFC’s ultimate ruling. Section title: V.A. Possible Solution: Allow Biosimilars to Start BPCIA Litigation at the Start of Phase 3 Clinical Trials Educational score: 1.3369560241699219 Domain: other Document type: Other Language: en Track Two would likely be attractive to many biosimilar firms who wish to enter the market earlier. By entering the market earlier, these biosimilars could benefit from less competition from other biosimilar firms thereby maximizing their revenues. Additionally, patients and payers benefit from earlier market entry because of decreased costs. Section title: V.A. Possible Solution: Allow Biosimilars to Start BPCIA Litigation at the Start of Phase 3 Clinical Trials Educational score: 1.1875544786453247 Domain: other Document type: Other Language: en This new track would likely need legislation because it would create a new type of patent dance. It would keep much of the original patent dance framework intact, but would allow an alternative pathway that was similar, except for the start of litigation, which would begin at the start of Phase 3 clinical trials instead of after the completion of the clinical trials. Section title: V.B. Comparison to the European and UK Patent Litigation Systems Educational score: 1.1989439725875854 Domain: other Document type: Other Language: en In various European countries, including the United Kingdom, generic and biosimilars are permitted to litigate the validity of patents at any time during their product development program. Generic drugs and biosimilars use the same patent litigation pathway. In the UK, Section 72(1) of the Patents Act (the ‘Act’) permits any person to apply for revocation of a patent via the UK Patents Court and it is not necessary to show locus standi. An application for revocation of a patent can be made at any time after notice of grant of the UK patent has been published in the Patents Journal. Section title: V.B. Comparison to the European and UK Patent Litigation Systems Educational score: 1.1195279359817505 Domain: other Document type: Other Language: en In Cairnstores v AB Hassle F.S.R. 35, the patent owner tried to have the revocation application struck out of court on the grounds that the other party appeared to have lack of trading activities. However, the court held that s.72 of the Act did not require a person applying to revoke a patent to have any interest, commercial or otherwise, in the outcome of the proceeding. Nonetheless, if the patent is eventually found to be valid, the challenger must reimburse the patent owner for the costs spent on the litigation. The policy behind the UK’s position appears to be that it is worthwhile to allocate court resources to remove invalid patents from the public domain. This stands in contrast to the ripeness requirement employed by US Courts, which allows litigation only at a much later stage thereby delaying biosimilar market entry. Section title: V.B. Comparison to the European and UK Patent Litigation Systems Educational score: 1.296103835105896 Domain: other Document type: Other Language: en UK courts incentivize generics and biosimilar firms to challenge patents at an early stage through the doctrine called ‘clearing the way’, which is an element necessary for injunctive relief. If the generic or biosimilar firm did not attempt to challenge the patent prior to launch, the brand biologic will be more likely to receive a preliminary injunction, thereby preventing biosimilar launch prior to the end of litigation. However, any pre-emptive patent challenge by the generic or biosimilar firm is rewarded by a reduced likelihood of preliminary injunction. Section title: VI. CONCLUSION Educational score: 1.8024910688400269 Domain: other Document type: Other Language: en Congress created the BPCIA as a mechanism to get biosimilar products onto the market faster. Unfortunately, the BPCIA has not demonstrated early market entry when compared to generic drugs. The BPCIA worked under the assumption that biosimilar firms would litigate on the same timeline as generic firms. However, this assumption was incorrect. In contrast to generics, biosimilars are required to undergo extensive clinical trials, leading to a substantial delay in market entry. Compounding the problem is delayed litigation because of lack of standing. One straightforward solution is to accelerate the timeline for litigation, allowing biosimilars earlier standing to trigger litigation. Safeguards such as litigation escrow accounts could be used to balance the rights of the brand biologic while incentivizing earlier biosimilar market entry and clearing erroneously granted patents to increase competition. To fulfill the intended objectives of the BPCIA, Congress should create a two-track system that grants biosimilars the option for earlier litigation. Section title: ROLE OF THE FUNDER Educational score: 1.0175544023513794 Domain: other Document type: Other Language: en The funder had no role in the design or conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. Section title: ACCESS TO DATA Educational score: 0.9489238262176514 Domain: other Document type: Other Language: en Drs Tu, Van de Wiele, and Goode had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Section title: FUNDING Educational score: 0.9004383087158203 Domain: other Document type: Other Language: en Dr Tu research is funded by Arnold Ventures. Section title: DISCLOSURES Educational score: 1.0184965133666992 Domain: other Document type: Other Language: en Dr Goode and Mr Turner are employees of Fresenius Kabi. Dr Tu reported consulting for purchasers of lenalidomide containing products outside the submitted work. | Other | biomedical | en | 0.999997 |
PMC11697979 | Section title: INTRODUCTION Educational score: 4.071028709411621 Domain: biomedical Document type: Study Language: en Plastics, predominantly derived from fossil fuels, have undeniably become a fundamental component of contemporary society . However, the accumulation of end-of-life plastics in the environment is causing a profound ecological crisis worldwide . In the pursuit of a circular economy, plastic waste is increasingly recognized as a valuable carbon resource that can be reintegrated into the chemical/material industry . Consequently, devising efficient methods for chemically transforming plastic waste into original precursors or a variety of functional and high-value chemicals is of paramount importance . Notably, chemical upcycling, which differs from traditional recycling techniques focused on monomer recovery, presents an advantageous route for enhancing plastic waste management by converting waste into value-added chemicals [ 7–10 ]. For example, polyolefins, known for their stability, are difficult to be transformed, but also versatile in their transformation capabilities. They can be converted into various mixture compounds such as mixture of alkanes , olefins , aromatics , or oxygenates . Notably, an elegant and innovative method has been recently reported which allows polyethylene (PE) to react with ethylene, producing a highly valuable single chemical, propene . Similarly, there has been substantial progress in developing new methods for the catalytic upcycling of different types of plastic wastes, as evidenced by various studies and advancements in the field [ 11–22 ]. Section title: INTRODUCTION Educational score: 4.266162872314453 Domain: biomedical Document type: Study Language: en Polyurethane (PU), containing urethane bonds and accounting for ∼6% of all plastic waste , is typically synthesized from isocyanates and polyols and comes in various forms, including foams, adhesives, and elastomers, depending on the monomers and additives used . Although PU can be relatively easily segregated from waste streams, the complexity of its monomers and its robust cross-linked structure make recycling or upcycling challenging. Techniques such as pyrolysis, hydrolysis, alcoholysis, aminolysis, acidolysis, and glycolysis have been explored for PU recycling [ 25–31 ], with methanolysis being a straightforward approach for depolymerization . Yet, the resulting low-value polyols and non-virgin monomers (methyl carbamates) from the cleavage of the –C(=O)–O– in urethane bonds make this method less attractive for further PU reproduction. An alternative, more effective method is catalytic hydrogenation, which breaks both –NH–C(=O)– and –C(=O)–O– bonds in an atom-efficient manner to recover basic monomers or derivatives. Several transformation systems have been successfully developed based on homogeneous catalytic hydrogenation [ 34–37 ], although their low thermal stability and the challenges in separating catalysts for reuse from reaction systems may limit their practical applications. Section title: INTRODUCTION Educational score: 4.102336883544922 Domain: biomedical Document type: Study Language: en We suggest that an effective upcycling strategy for PU should incorporate a carefully engineered heterogeneous catalytic system, which integrates methanolysis with hydrogenation processes. In this context, our proposed strategy involves using CO 2 /H 2 as the reaction medium along with a heterogeneous catalyst. This catalyst is uniquely designed to facilitate both the conversion of CO 2 to methanol and the hydrogenation of plastic depolymerization reaction intermediates. This comprehensive approach is anticipated not only to improve the depolymerization efficiency of PU waste and the utilization of CO 2 waste, but also enable a complete recovery of the designated components. Importantly, we aim to transform these components into valuable materials for the valorization of plastic waste. Section title: INTRODUCTION Educational score: 4.281963348388672 Domain: biomedical Document type: Study Language: en Here we introduce a novel two-step reaction construct to convert polyurethane (PU), containing urethane and ester bonds, into two valuable polymers: polyimide (PI, an engineering plastic) and polylactone (P(BL- co -CL), a biodegradable plastic), as illustrated in Fig. 1 . During the initial heterogeneous depolymerization step of PU, we employed a mixture of CO 2 /H 2 , a highly effective combination for the catalytic hydrogenative depolymerization of PU into diamines, diols, and lactones. This process achieved a total product yield of 86% using an inverse ZnO-ZrO 2 /Cu catalyst at 200°C. Subsequently, the produced 1,4-butanediol (BDO) was further converted into γ-butyrolactone (BL) using the same catalyst at 220°C. In the subsequent step, the obtained diamine and lactones were utilized to synthesize PI and P(BL- co -CL), respectively. Remarkably, from 5 g of waste tyre material, predominantly composed of PU, we successfully produced ∼2.2 g of PI films. These films demonstrated excellent energy-storage capabilities, functioning as dielectric capacitors with a discharge energy density ( U e ) of 6.0 J cm −3 at 150°C. Concurrently, we also generated ∼0.44 g of polylactone, exhibiting both satisfactory chemical recyclability and ductile properties. This innovative approach not only paves a new path for upcycling PU waste into a range of valuable and functional polymers but also contributes to the realization of a sustainable future. Section title: RESULTS AND DISCUSSION Educational score: 4.0680742263793945 Domain: biomedical Document type: Study Language: en First, we synthesized an inverse ZnO-ZrO 2 /Cu catalyst using a method similar to a previously reported procedure , with the characterizations presented in Figs S1 and S2 ( Supplementary data , XRD and N 2 physisorption analysis). This catalyst was selected for testing the hydrogenative depolymerization of PU in a CO 2 /H 2 environment, motivated by the known efficacy of inverse Cu-based catalysts in converting CO 2 to methanol and hydrogenating polyesters . Section title: RESULTS AND DISCUSSION Educational score: 4.239668846130371 Domain: biomedical Document type: Study Language: en We then evaluated this catalyst for degrading two types of polyurethane: a synthetic PU1, composed of urethane bonds created from the reaction of 4,4'-methylenedianiline with triethylene glycol (TEG), and a commercial PU2, containing both urethane and ester bonds . These were chosen as model feedstocks, with PU1 representing a simpler urethane-only structure and PU2 being more representative of real-world plastics. Remarkably, both PU1 and PU2 were completely converted within 4 hours at 200°C under CO 2 /H 2 conditions (1/3, v/v, 3 MPa) over inverse ZnO-ZrO 2 /Cu catalyst, leaving no residual PUs as confirmed by Fig. 2a, b , and Figs S3–S6 . The catalytic depolymerization yielded three types of products: aromatic amines (4,4′-methylenedianiline ( a ); 4-(4-aminobenzyl)- N -methylaniline ( b ); 4,4′-methylenebis( N -methylaniline) ( c )), diols (TEG from PU1; BDO and dipropylene glycol (DPG) from PU2), and lactones (BL and ε-caprolactone (CL) from PU2), as shown in Fig. 2a . The product yields were impressive, at 89% for PU1 and 82% for PU2 under condition 1 . Additionally, methanol formation was observed, arising from the CO 2 hydrogenation reaction . This indicates that an effective heterogeneous catalytic system for the degradation of polyurethanes has been successfully established. The mass balance of the catalytic process was calculated through dividing the mass of obtained products related to monomers by the total mass input of polyurethane. Although the calculation does not exclude the involed mass of hydrogen and methyl group from CO 2 , the mass balance is still appropriate to evaluate the efficiency of recovered products from depolymerization of polyurethane. The lower yield of obtained products from depolymerization of polyurethane at higher temperature may be due to the formation of N -alkylated byproducts between diamines and diols. Section title: RESULTS AND DISCUSSION Educational score: 4.137024879455566 Domain: biomedical Document type: Study Language: en We envision that CO 2 plays a crucial role in generating methanol, which in turn accelerates the hydrogenative depolymerization of PU. To test this hypothesis, we conducted depolymerization studies under various reaction conditions . Initially, we assessed the catalytic depolymerization performance using either hydrogen (2.2 MPa) or a stoichiometric amount of methanol (2 mmol) alone . In both scenarios, we observed a significant reduction in product yields, underscoring the efficacy of the CO 2 /H 2 combination for efficient catalytic degradation. Notably, the yields in hydrogen (PU1: 51%; PU2: 36%) were substantially higher compared to those in methanol (PU1: 31%; PU2: 21%), suggesting hydrogen's primary role in the hydrogenative deconstruction of PU. Section title: RESULTS AND DISCUSSION Educational score: 4.205775737762451 Domain: biomedical Document type: Study Language: en Subsequently, we conducted a control reaction with both hydrogen (2.2 MPa) and a stoichiometric amount of methanol (2 mmol) . While the activities were comparable, the product yields (PU1: 81%; PU2: 76%) were slightly lower than under condition 1. However, it confirmed the pivotal role of methanol generated in-situ from CO 2 in the depolymerization process. Moreover, in experiments using only hydrogen or tetrahydrofuran (THF) solvent without the catalyst , only lactone products were obtained from PU2. This indicates that hydrogenative depolymerization predominantly occurs over the ZnO-ZrO 2 /Cu catalyst and that the ester bond in PU2 can be partially broken down in THF solvent. To further discriminate the catalytic active sites in the reduction of CO 2 to methanol, the methanolysis and hydrogenolysis reactions of PU, we carefully investigated the catalytic processes by changing different reaction conditions . In the CO 2 reduction process, Cu species were the main active sites, and a Zn additive promoted the catalytic reduction activity. In the catalytic hydrogenolysis processes, Cu species were the main catalytic active sites for the cleavage of urethane bonds. Section title: RESULTS AND DISCUSSION Educational score: 4.138556003570557 Domain: biomedical Document type: Study Language: en The efficiency of the depolymerization processes for PU1 and PU2 was thoroughly analyzed using gel permeation chromatography (GPC) to measure the materials recovered from the reactions . A distinctive observation was that, under CO 2 /H 2 reaction conditions , no polymer signals were detected. This highlights the exceptional capability of the designed catalytic system for effective PU degradation. Intriguingly, the process also yielded valuable methylated amines , which are known to play a crucial role in modulating biological and pharmaceutical activities in life science molecules . The methyl groups in these compounds are believed to originate from CO 2 , as evidenced by experiments under various reaction conditions . This suggests a sustainable carbon-fixation process, further emphasizing the environmental and industrial relevance of this catalytic method. Section title: RESULTS AND DISCUSSION Educational score: 4.322715759277344 Domain: biomedical Document type: Study Language: en To further understand the cleavage of urethane bonds during the hydrogenative depolymerization process, a small model compound (Model 1, propyl p -tolylcarbamate) was synthesized . Since the compound only contains –NH–C(=O)– and –C(=O)–O– bonds that can be cleaved, it can be effectively converted into aromatic amines (4-methylaniline (MA), N ,4-dimethylaniline (DMA), and 4-methyl- N -propylaniline (MPA)) and 1-propanol (Pol) with a total yield of 98% over ZnO-ZrO 2 /Cu in the presence of CO 2 /H 2 . The formation of DMA and MPA indicates that N-alkylation occurred during the process. Obviously, the total product yield decreased to 80% under the hydrogen atmosphere , suggesting the lower efficiency of catalytic hydrogenation of the ester bonds. In addition, an excessive amount of methanol was used to visualize its effect during catalytic hydrogenation of the urethane bond under an inert atmosphere. In contrast, the total product yield toward MA and Pol was only 47%. The process was achieved along with formation of other N -methylated products (DMA and N,N ,4-trimethylaniline (TMA)) and methanolysis products (methyl p -tolylcarbamate (MTC) and N - p -tolylformamide (TFA)) with a yield of 43% . The formations of MTC and TFA can present intermediates for insight into the reaction mechanism during catalytic depolymerization of polyurethane, demonstrating that the effective cleavage of –C(=O)–O– bond precedes the –NH–C(=O)– bond in the presence of methanol. Moreover, the generated N -methylated products suggest that excessive methanol in the catalytic system is unfavorable for producing primary amines. Section title: RESULTS AND DISCUSSION Educational score: 4.084858417510986 Domain: biomedical Document type: Study Language: en Considering that the complex composition and additives in commercial PU plastics could potentially affect the efficiency of our designed catalytic system, we evaluated its robustness using four different commercial PU products: a shoe sole, a tube, a tyre, and a safety strip . The catalytic degradation of each of these PU plastics (400 mg each) was assessed, and the results are displayed in Fig. 3b . The total product yields from the catalytic depolymerization were found to be 77%, 80%, 86%, and 82% for the shoe sole, tube, tyre, and safety strip, respectively . These results underscore the effectiveness of our catalytic method in hydrogenatively depolymerizing various commercial PU plastics, despite their differing compositions. Taking the PU tyre as a case study, which contained the highest proportion of urethane linkage ( Table S1 ), we observed consistent catalytic performance over six repeated cycles of transformation . This consistent performance is a testament to the excellent stability of our catalytic system, indicating its potential for practical applications in recycling and upcycling commercial PU plastics. Section title: RESULTS AND DISCUSSION Educational score: 4.168891906738281 Domain: biomedical Document type: Study Language: en We subsequently conducted a scaled-up deconstruction of a 5 g PU tyre sample to extract basic chemicals for further processing . This procedure was executed with exceptional catalytic efficiency, as shown in Fig. 3e . Following purification by flash column chromatography, we isolated 0.90 g of compound a , 0.71 g of compound b , 0.95 g of BDO, and 0.45 g of lactones (BL and CL) . Given the value of BL as a precursor for biodegradable plastics, we converted the obtained BDO into BL using a straightforward dehydrogenation method . This reaction employed the same ZnO-ZrO 2 /Cu catalyst at 220°C under a nitrogen atmosphere, resulting in a BL yield of 96% over 12 hours . This BL was then combined with the lactones obtained in the initial step, yielding a total of 1.3 g of lactones (BL/CL ratio of 11/1, mol/mol) . Additionally, both the fresh and spent ZnO-ZrO 2 /Cu catalysts underwent comprehensive characterization using techniques such as XRD, X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge structure (XANES) spectroscopy, extended X-ray absorption fine-structure (EXAFS), and transmission electron microscopy (TEM) . These analyses revealed no significant changes, confirming that the crystalline phase, chemical valence, coordination environment, and morphology of the ZnO-ZrO 2 /Cu catalyst remains highly stable throughout the catalytic processe. Section title: RESULTS AND DISCUSSION Educational score: 4.0313720703125 Domain: biomedical Document type: Study Language: en Aromatic diamines and lactones are key building blocks for diverse applications. In our strategy, the aromatic diamines and lactones obtained from the process were utilized to synthesize two high-value polymers: polyimide (PI) and polylactone (P(BL- co -CL)). As depicted in Fig. 1 , the 4,4′-methylenedianiline (0.9 g) derived from the PU tyre was reacted with dianhydrides—specifically, pyromellitic dianhydride (PMDA) and 4,4′-(hexafluoroisopropylidiene)diphthalic anhydride (6FDA)—to produce two types of PI films (PI1 and PI2, respectively) as shown in Fig. 4a and b . PI is a crucial engineering plastic, prized for its exceptional thermal stability, electrical insulation, and high mechanical strength . Section title: RESULTS AND DISCUSSION Educational score: 4.203372955322266 Domain: biomedical Document type: Study Language: en The successful synthesis of PI films was confirmed by infrared (IR) analysis, which revealed characteristic vibration peaks: at 710 cm −1 (imide ring), 1365 cm −1 (C–N stretch), 1715 cm −1 (C=O symmetric stretch), 1780 cm −1 (C=O asymmetric stretch), and between 2850 and 2950 cm −1 (C–H stretch associated with the –CH 2 – moiety) . The properties of the synthesized PI1, PI2, and commercial Kapton films were compared. All films demonstrated excellent solvent resistance, remaining insoluble in various solvents (DCM, NMP, DMF, THF, and DMSO) as shown in Fig. S20 . Their thermal stability was assessed using thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA) . The findings showed that the 5% weight loss temperatures and glass transition temperature ( T g ) of all films were above 450°C and 300°C, respectively, indicating superior thermal resistance. Additionally, the dielectric properties of the films, including the dielectric constant and loss tangent, were evaluated at a high temperature of 150°C . These properties remained stable across a frequency range of 10 to 10 7 Hz, demonstrating excellent dielectric stability and endurance under high voltage conditions. Section title: RESULTS AND DISCUSSION Educational score: 4.141779899597168 Domain: biomedical Document type: Study Language: en The PI1 and PI2 films synthesized in our study show great promise as dielectric materials for high-temperature capacitors. In comparison to commercial Kapton, the synthetic PI1 and PI2 films demonstrated notably higher maximum discharge energy densities ( U e ) of 2.4 and 6.0 J cm −3 , respectively, with charge-discharge efficiencies ( ƞ ) exceeding 90% at 150°C . This superior performance is likely attributable to their larger band gap compared to commercial Kapton, as evidenced in Fig. S22b . Furthermore, the PI2 film maintained its excellent performance, with a U e of 2.6 J cm −3 and η >90%, even under more challenging conditions at 200°C . This resilience under extreme temperatures highlights the potential of PI2 for advanced applications. Thus, the aromatic diamine recovered from the catalytic degradation of PU plastic waste is not just recycled but significantly upgraded into PI films with competitive properties, as shown in Fig. S23b . This transformation represents a major stride forward in converting waste materials into high-performance products. Section title: RESULTS AND DISCUSSION Educational score: 4.285059452056885 Domain: biomedical Document type: Study Language: en In parallel to producing polyimide, we utilized the lactones (1.3 g, BL/CL = 11/1, mol/mol) derived from the PU tyre to synthesize the biodegradable copolyester, P(BL- co -CL), through a ring-opening copolymerization reaction . Notably, P(BL- co -CL) is a green alternative to petrochemical-based polyolefins , first introduced by Chen et al. . We employed an yttrium complex supported with tetradentate aminoalkoxy-bis-phenolate ligands ( Y-N ), a highly efficient catalyst for the ring-opening polymerization of cyclic esters , for the copolymerization of the relatively ‘nonstrained’ BL and the more ‘strained’ CL. The copolymerization was conducted at −30°C to minimize the effect of the − T Δ S term on the Δ G of the reaction. After 17 hours, the random copolymer P(BL- co -CL) (Mn = 56.3 kg/mol, polydispersity index (Ð) = 1.41) was obtained, with a 73.5% incorporation of BL, alongside a conversion rate of 26.8% for BL and 93.7% for CL . Its thermal properties, analyzed via TGA and differential scanning calorimetry (DSC), revealed a decomposition temperature at 5% weight loss ( T d ) of 226°C , along with a crystallization temperature ( T c ) of −20.9°C and a melting temperature ( T m ) of 17.9°C, characterizing it as a semicrystalline random copolymer . Section title: RESULTS AND DISCUSSION Educational score: 4.27830696105957 Domain: biomedical Document type: Study Language: en The synthetic P(BL- co -CL) exhibited excellent mechanical properties, with a toughness of 171 MPa and an impressive elongation at break ( ε B ) of over 1000%, as determined by tensile testing of dog-bone-shaped samples at 5°C . These values surpass those of the corresponding homopolymers, poly (γ-butyrolactone) ( ε B <400%) and poly (ε-caprolactone) ( ε B ≈700%) . The copolymer also displayed an ultimate tensile strength ( σ B ) of 25.0 MPa and Young's modulus ( E ) of 228 MPa , comparable to poly(ethylene terephthalate) and low-density polyethylene . Remarkably, the synthetic P(BL- co -CL) can be fully recycled back to its original monomers (BL and CL) with a near-quantitative conversion rate of over 98% by heating at 250°C for 12.5 hours in the presence of Y(CH 2 SiMe 3 ) 3 (THF) 2 (5 mol%) . The composition of the recycled BL/CL was ∼2.75/1, aligning with the initial composition in P(BL- co -CL). Therefore, the lactones sourced from waste PU tyre have been successfully transformed into P(BL- co -CL) with outstanding chemical recyclability and ductility. Section title: CONCLUSION Educational score: 4.150876998901367 Domain: biomedical Document type: Study Language: en In conclusion, this study presents an efficient approach for the upcycling of PU waste, utilizing a novel catalytic process that transforms PU into important chemicals and then valuable polymers. By employing a heterogeneous catalytic system combining methanolysis and hydrogenation, we effectively depolymerized PU into aromatic diamines and lactones in CO 2 /H 2 media. These intermediates were then used to synthesize high-value polymers: polyimide (PI) for advanced engineering applications and polylactone (P(BL- co -CL)) as a biodegradable alternative to traditional plastics. The PI films demonstrated exceptional thermal and dielectric properties, while the synthesized P(BL- co -CL) exhibited remarkable ductility and recyclability. Our approach not only addresses the valorization of PU plastic waste but also offers a sustainable pathway for converting waste into high-performance materials, contributing to a circular economy. | Study | biomedical | en | 0.999998 |
PMC11697981 | Section title: INTRODUCTION Educational score: 4.035601615905762 Domain: biomedical Document type: Study Language: en Deoxyribonucleic acid (DNA) has recently received significant attention as a promising candidate for data storage media owing to its extended lifespan and inherent storage density [ 1–4 ], especially for cold data, which refers to data with low access frequency and reading speed requirements, but with large volumes that need to be stored and managed for the long term . Specifically, examples include three-dimensional medical imaging data , planetary science data monitoring changes in planetary states and meteorological data documenting weather fluctuations . These datasets typically require large-scale data volumes and persistent archiving for historical trend analysis and retrospective research, resulting in high storage costs when stored using conventional storage media. By examining the characteristics of such datasets, we observed that they commonly consist of multiple files generated at different time points, sharing the same format, and containing inherent continuous content. In the context of this study, we refer to them as time-series archival datasets. Section title: INTRODUCTION Educational score: 4.157925605773926 Domain: biomedical Document type: Study Language: en Besides, strict scientific standards require high accuracy in the recovery of such data. However, due to the unpredictability of biochemical reactions during the synthesis, manipulation and sequencing processes, the DNA data storage process is error prone . To enhance the reliability of DNA data storage, various concatenated codes have been proposed. In the process of inferring the order of disordered and duplicate DNA sequencing reads, the outer code typically assigns a unique index to each encoded oligonucleotide (oligo), enabling the identification of its location. Consequently, dropout errors can be treated as erasure errors. Erasure codes, such as the DNA fountain code [ 11–13 ], indexed Reed–Solomon (RS) code and Low-density Parity-check (LDPC) code , are proven effective in restoring the missing information. We refer to them as index-added encoding strategies. Meanwhile, several error-correcting codes, including the watermarker code , RS code , HEDGES code , DNA-Aeon code , Derrick code and SPIDER-WEB code are considered valid inner codes for checking and correcting nucleotide errors. Section title: INTRODUCTION Educational score: 3.5802173614501953 Domain: biomedical Document type: Study Language: en While numerous studies have proposed many coding schemes for DNA data storage, there is still potential for designing an encoding method that better adapts to time-series archival datasets. Moreover, most studies compress the raw information before encoding, which can lead to complete failure of data recovery even with a minor error. This phenomenon has been found in many studies . Current compression algorithms are not tailored for DNA data storage and are not suitable for scenarios with high error rates. It inspires us not to use compression algorithms, but to focus on the characteristics of the raw information itself, so as to design an adaptive encoding method to improve information density and correct errors. Section title: INTRODUCTION Educational score: 4.265876770019531 Domain: biomedical Document type: Study Language: en To achieve this goal, considering the characteristics of time-series archival datasets, we proposed a novel coding method called the DNA palette code. The main features of our coding scheme are that it does not require indexing, and can achieve high information density (i.e. the ratio of input bit information to the number of synthetic DNA nucleotides, excluding primers and adapters ) and a low decoding sequence coverage rate (i.e. the number of reads required to recover 100 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\%$\end{document} information divided by the number of encoded oligos). In scenarios where sequencing coverage is very low, leading to high dropout rates and byte error rates, the decoder is still capable of recovering partial information. Our coding scheme is resilient to residual byte errors, allowing it to recover partial information to prevent complete data loss even in the presence of such errors. We verified the performance of the DNA palette code by simulation and experimental validation. In our in vitro test, we encoded 11.28 MB of clinical brain magnetic resonance imaging (MRI) data into 255 248 oligos of 155-nt length (data payload only, no primers and adapters). The information was successfully recovered with 100 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\%$\end{document} accuracy at a median average coverage of 4.4 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\times$\end{document} . When the sequencing coverage is 2 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\times$\end{document} , the recovered pixel data can also provide medical information. Furthermore, we conducted simulations on a large public MRI dataset (10 GB) and two other applications (including observations of the Earth’s plasmasphere by the extreme ultraviolet camera on the Chang’E-3 Moon lander and daily melt results on the surface of the Greenland ice sheet). This illustrates the robustness and broad application of the DNA palette code. Section title: RESULTS Educational score: 4.115414619445801 Domain: biomedical Document type: Study Language: en A brain MRI scan yields a significant volume of slice data, where each slice is stored as an individual digital imaging and communications in medicine (DICOM) file . Adhering to the DICOM format , we introduced a data pre-processing scheme based on dictionary transforms, called the DNA ladder code, which can utilize the structural information of the dataset to convert it into a form more conducive to the DNA palette code encoding . Subsequently, we presented a ‘bit-to-oligo’ mapping approach grounded in combinatorial theory, termed the DNA palette code . The decoder undertakes trace reconstruction and nucleotide error-correcting tasks, accommodating duplicate sequencing reads without the need for clustering or multiple alignments . The DNA palette code is the major innovation, so we use it to refer to the coding scheme proposed in this work. Section title: DNA palette code Educational score: 4.351205348968506 Domain: biomedical Document type: Study Language: en The fundamental idea of the DNA palette code is to establish a bijection between \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {X}^N$\end{document} , the range of the raw information, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}$\end{document} , the family of oligo sets. Here, we use \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {X} = \lbrace 0,1\rbrace$\end{document} to denote the binary alphabet and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {D} = \lbrace \text{A},\text{T},\text{G},\text{C}\rbrace$\end{document} to represent four natural DNA nucleobases: adenine (A), cytosine (C), guanine (G) and thymine (T). The codeword corresponding to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{x} \in \mathcal {X}^n$\end{document} is a subset of the oligo set. Metaphorically, the DNA palette code regards each oligo as a pigment, distinguishing different binary strings by coloring them with distinct colors. It enables the mixing of different pigments to create new colors. Assuming that mixed colors are distinct, and pigments exhibit a total order relation, the resulting mixed colors will possess a lexicographical order defined by this relation. Similarly, we have also defined a total order on the range of the raw information. This allows us to establish a one-to-one mapping between binary strings and colors through these two total order relations. Consequently, the input can be uniquely encoded as a color. Since pigments are mixed without regard to the order or quantity added, the number of pigments used for encoding binary strings is not fixed and no index needs to be inserted for each pigment. Section title: DNA palette code Educational score: 4.301301956176758 Domain: biomedical Document type: Study Language: en When considering oligos as pigments, the mixing process of pigments can be viewed as sampling without replacement within the set of oligos. Here is a straightforward example. Let ‘001’ be the raw information, and let \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O = \lbrace \boldsymbol{o}_1, \boldsymbol{o}_2, \boldsymbol{o}_3\rbrace$\end{document} be the preset oligos. The range of the raw information is \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {X}^3 = \lbrace 000, 001, 010, 100, 011, 101, 110, 111\rbrace$\end{document} , and the family of oligo sets is \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}^3 = \lbrace O_0, O_1, \ldots , O_7\rbrace$\end{document} , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O_0 = \emptyset$\end{document} , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O_1 = \lbrace \boldsymbol{o}_1\rbrace$\end{document} , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O_2 = \lbrace \boldsymbol{o}_2\rbrace$\end{document} and so on, up to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O_7 = \lbrace \boldsymbol{o}_1, \boldsymbol{o}_2, \boldsymbol{o}_3\rbrace$\end{document} . We can define a map to encode sequences in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {X}^3$\end{document} to oligo sets in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}^3$\end{document} , such as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $000 \mapsto O_0$\end{document} , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $001 \mapsto O_1$\end{document} and so forth. The decoder can determine the raw information by identifying which oligo was received. Notably, the number of encoded oligos is not fixed due to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $|O_0| \ne |O_1|$\end{document} . This is a key feature of our encoding scheme, allowing fewer oligos/nucleotides than expected to represent the raw information. Specifically, using a typical transcoding method (e.g., 00 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\leftrightarrow$\end{document} A, 01 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\leftrightarrow$\end{document} T, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $10 \leftrightarrow {\rm G}$\end{document} , 11 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\leftrightarrow$\end{document} C), ‘001’ would be encoded as ‘AT’. In contrast, our method would encode ‘001’ into \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O_1 = \lbrace \boldsymbol{o}_1\rbrace = \lbrace \text{A}\rbrace$\end{document} when \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O = \lbrace \text{A, T, G}\rbrace$\end{document} . Section title: DNA palette code Educational score: 4.161932945251465 Domain: biomedical Document type: Study Language: en For a longer binary information sequence (i.e. \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{x}\in \mathcal {X}^N$\end{document} ) and a preset oligo set \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $O=\lbrace \boldsymbol{o}_1,\boldsymbol{o}_2,\ldots ,\boldsymbol{o}_n\rbrace \subseteq \mathcal {D}^m$\end{document} ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $n> N$\end{document} ), we designed a map f to encode this binary information into an oligo set. Firstly, the order ‘ \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $< $\end{document} ’ of these preset oligos is defined as follows: for any \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}_1 = (o_1^1, o_2^1, \ldots , o_m^1) \in \mathcal {D}^m$\end{document} and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}_2 = (o_1^2, o_2^2, \ldots , o_m^2) \in \mathcal {D}^m$\end{document} , if there exists i such that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $o_1^1 = o_1^2, o_2^1 = o_2^2, \ldots , o_{i-1}^1 = o_{i-1}^2$\end{document} and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $o_i^1 < o_i^2$\end{document} then \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}_1 < \boldsymbol{o}_2$\end{document} . The order of nucleotides is \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\rm A} < {\rm T} < {\rm G} < {\rm C}$\end{document} . For example, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\rm AAT} < {\rm AAG} < {\rm ATT}$\end{document} . It can be easily proved that this order is transitive, antisymmetric and strongly connected, thus constituting a total order on \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {D}^m$\end{document} . Without loss of generality, we defined \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}_1< \boldsymbol{o}_2< \cdots < \boldsymbol{o}_n$\end{document} . Then we defined a total order on \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}$\end{document} , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}$\end{document} is the family of the subsets of O : for \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $A=\lbrace \boldsymbol{o}^{A}_1,\boldsymbol{o}^{A}_2,\ldots ,\boldsymbol{o}^{A}_{m}\rbrace \subseteq O$\end{document} and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $B=\lbrace \boldsymbol{o}^{B}_1,\boldsymbol{o}^{B}_2,\ldots ,\boldsymbol{o}^{B}_s\rbrace \subseteq O$\end{document} , (i) if there exists j such that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}^{A}_m=\boldsymbol{o}^{B}_s$\end{document} , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}^{A}_{m-1}=\boldsymbol{o}^{B}_{s-1}$\end{document} ,..., \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}^{A}_{m-j+1} =\boldsymbol{o}^{B}_{s-j+1}$\end{document} , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{o}^{A}_{m-j}< \boldsymbol{o}^{B}_{s-j}$\end{document} , then \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $A< B$\end{document} ; (ii) otherwise, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $B< A$\end{document} . Next, we defined a map \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $f:\mathcal {X}^N \rightarrow \mathcal {O}^N$\end{document} such that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $f(\boldsymbol{x})$\end{document} is the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $(\sum _{i=1}^N2^{i-1}x_i)$\end{document} th set in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}$\end{document} . Here, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}^N$\end{document} denotes the first \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $2^N$\end{document} sets of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\mathcal {O}$\end{document} . It is easy to prove that f is a bijection. According to the map f , the raw binary information \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\boldsymbol{x}$\end{document} will be encoded into \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $f(\boldsymbol{x})$\end{document} . The decoder can recover the raw information via \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $f^{-1}$\end{document} , where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $f^{-1}$\end{document} is determined when given O and N . Section title: DNA palette code Educational score: 1.5818631649017334 Domain: other Document type: Other Language: en The above encoding scheme requires that both the encoder and decoder know the one-to-one mapping alphabet. This may pose a challenge when storing large-scale datasets. We propose a nested mapping method, as shown in Fig. 1b and Fig. S2 . This method splits the large mapping into a cascade of two small mappings. The details of the nested encoding scheme are shown in Section S1.1 within the online supplementary material . Besides, In practice, we adopted the nested mapping and presented the encoded oligos to satisfy the VT structure [ 23–25 ]. Section title: DNA palette code Educational score: 4.241449356079102 Domain: biomedical Document type: Study Language: en The decoding algorithm of DNA palette code can be regarded as a trace reconstruction process aimed at recovering the correct set of oligos from duplicate sequencing reads . Specifically, each read undergoes an initial check for compliance with the VT structure, encompassing error-correcting and verification processes. Subsequently, the reads are grouped and selected by the majority vote algorithm. Following these two steps, a substantial portion of the encoded oligos can be successfully restored. Notably, our decoder takes duplicate sequencing reads as input, rather than using the central sequence obtained from clustering or multiple sequence alignment algorithms as input. The decoding complexity of the majority vote algorithm scales linearly with the number of sequencing reads. Additionally, in adherence to the total order sorting rules, bits/oligos can be directly placed in their respective positions without necessitating the comparison and exchange process. This results in linear encoding and decoding complexity relative to the number of bits/oligos. Section title: DNA palette code Educational score: 4.054217338562012 Domain: biomedical Document type: Study Language: en Upon recalling the encoding process of the DNA palette code, it is noted that the number of encoded oligos is related to the Hamming weight of the raw binary information. To this end, we proposed a data pre-processing method called the DNA ladder code to convert the raw information into a new form containing a large number of zeros. This algorithm encompasses three stages: label alignment, differential encoding and block RS encoding. The initial two stages modify the structure of the raw information without introducing redundancy, while the third stage incorporates parity-check bits to address errors. Specifically, residual errors in the DNA palette decoder and the occurrence of dropout oligos might lead to a partial loss of information in the decoded binary string, which can be recovered through the RS code. A comprehensive description of the DNA ladder code is available in Section S1.3 . Section title: Testing in vitro Educational score: 4.071786880493164 Domain: biomedical Document type: Study Language: en In the in vitro experiment, we stored the medical imaging data from two brain MRI examinations of a patient with ischemic cerebrovascular disease conducted in November 2021 and October 2023. Each examination produced 21 DICOM files ( Data S1 ). The 42 DICOM files, totaling 11.28 MB, were encoded into 255 248 oligos, each with a length of 155 nt . The encoded oligos were synthesized by Twist Bioscience. The DNA pool was amplified through polymerase chain reaction, followed by a sequencing procedure on the Illumina sequencing platform. The mean coverage (i.e. the total number of reads divided by the number of encoded oligos) was 256 reads . Section title: Testing in vitro Educational score: 4.202755451202393 Domain: biomedical Document type: Study Language: en During the decoding process, we randomly sampled sequencing reads and gradually increased the sampling coverage. The sampling command is shown in Section S3.4 . When the mean value of sampling coverage is 5 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\times$\end{document} , the dropout rate is 1.63 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\%$\end{document} . As the average sequence coverage increases, the byte error rate (i.e. the byte error rate in the decoded output) decreases significantly, and the decoding time increases linearly . The minimum average coverage rates of the two examination files are 4.2 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\times$\end{document} and 4.6 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\times$\end{document} with a median of 4.4 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\times$\end{document} (Table 1 ). The format of the elements is the number of successful decoding times compared to the number of tests. The specific experimental results are shown in Tables S1–S4 . Images generated from decoded pixel information at different coverage rates are shown in Fig. 2c . In the presence of byte errors, mosaic artifacts may appear in the image; however, most of the information is still discernible. This shows that our decoder can recover part of the original data when only a partial sequencing read is received. It differs from compression algorithms such as DEFLATE, where even minor fragment loss can render the compressed data completely unrecoverable . The decoded data can be used for three-dimensional (3D) reconstruction of medical images, such as the maximum intensity projection image and 3D volume rendering image . Besides, the number of encoded oligos for the first MRI examination is less than the index-added method . Here, ‘without DNA palette encoding’ denotes the scenario where the raw information is sequentially encoded into oligos, and the oligo index is added. The redundancy of its error-correcting code is the same as that of the DNA palette code. This suggests that, for MRI data, the DNA palette code can encode information using fewer oligos. Section title: Simulation on large data scales and diverse data formats Educational score: 4.239841461181641 Domain: biomedical Document type: Study Language: en First, to evaluate the performance of our coding scheme under a large data scale, we collected 10-GB DICOM files from public MRI datasets . Simulations show that the DNA palette code has a stable effect on reducing the number of encoded oligos . When the coding redundancy is fixed, the number of encoded oligos can be reduced by approximately \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $1/3$\end{document} through DNA palette coding. We further conducted a series of simulations on random data with sizes ranging from 10 MB to 10 GB. The encoding time and the decoding time of the DNA palette code are linear in the length of the input . This is consistent with the results of the theoretical analysis. Our coding scheme also performs well in error handling across different DNA error rates and the number of duplicate sequencing reads . Here, we assumed that the IDS error rates are equal, and the total error rate is \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} ${\rm pr}= p_{\rm ins}+p_{\rm del}+p_{\rm sub}$\end{document} . The dropout rate \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $p_{\rm drop}=5\%$\end{document} and the duplication number M ranges in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\lbrace 1,3,5,10\rbrace$\end{document} . We also tested the byte error rates when there were only substitution, dropout, deletion and insertion errors . Experimental data analysis based on Twist synthesis and Illumina sequencing technology shows that the raw error rate of the DNA data storage system is less than \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $1\%$\end{document} . Simulations indicate that our coding scheme can achieve error-free decoding at such an error rate. Section title: Simulation on large data scales and diverse data formats Educational score: 4.107781410217285 Domain: biomedical Document type: Study Language: en We further tested our coding scheme on many different data formats. The first is the Planetary Data System (PDS) data format, which is a standardized form used for the archiving and distribution of planetary science data. Files in Table 2 record the Earth’s plasmasphere observations acquired by the extreme ultraviolet camera onboard the Chang’E-3 lander ( Data S2 ) . The second is the NetCDF Network Common Data Form (NetCDF), which is a software library and self-describing machine-independent data format that supports the creation, access and sharing of array-oriented scientific data. Files in Table 3 are based on the threshold method of the microwave radiometer’s day and winter brightness temperature difference to extract the Greenland ice sheet surface melt from the downscaling results, and obtain the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $0.05^\circ$\end{document} daily melt results of the Greenland ice sheet surface in 1985, 2000 and 2015 ( Data S3 ) [ 29–34 ]. Encoding results show that our coding scheme works well for such time-series archival datasets. Compared with the DNA fountain code, our code can effectively reduce the number of encoded nucleotides . Here, ‘ \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $r({b}/{n})$\end{document} ’ refers to the ratio of the number of bits in the binary form of the file divided by the number of encoded nucleotides. Simulations show that our coding scheme is capable of error-free decoding in a wide range of data formats (panels (e) and (f) of Fig. 3 ). Section title: DISCUSSION Educational score: 3.8408544063568115 Domain: biomedical Document type: Study Language: en In the DNA data storage system, short DNA strands are stored in a spatially disordered structure within a three-dimensional space. Decoders typically require additional information to determine the order of the DNA strands to restore the original bitstream. The DNA palette code is designed to accommodate this feature. It is based on a sampling without replacement method, using unordered combinations of oligos to indicate binary information. The encoded oligos do not contain indexes and are not fixed in number when encoding different binary strings of the same length. When the DNA palette code is combined with contextual transformation methods (such as our proposed DNA ladder code), we can encode time-series archival data with fewer oligos than expected. Section title: DISCUSSION Educational score: 4.150411605834961 Domain: biomedical Document type: Study Language: en Additionally, rather than employing a compression algorithm, we developed a direct transcoding method that converts raw information bits to nucleotides. Our coding scheme demonstrates resilience in recovering information even in scenarios characterized by high dropout rates and byte error rates. Specifically, even when the received sequencing data are significantly insufficient and the error rate is high, such as when the dropout rate exceeds \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $15\%$\end{document} and the byte error rate exceeds 9% , our code can recover part of the raw information. In addition, our method can achieve a net information density of more than 2 bits/nt when encoding time-series archival data, which has the effect of a compression algorithm, while avoiding the problem of being unable to recover information when there are a small amount of residual errors in the decoded data due to the use of a compression algorithm (such as the DEFLATE algorithm). Section title: DISCUSSION Educational score: 4.112607002258301 Domain: biomedical Document type: Study Language: en We verified the effectiveness of our code in DNA data storage systems through wet and dry experiments. In our wet experiment, we encoded 11.28-MB MRI data into 255 248 oligos with a length of 155 nt, whereas the expected oligo number is 397 972. As shown in Table 4 , compared with other studies, our wet experiment stored an average of 2.39 bits in one nucleotide and achieved 100 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\%$\end{document} data recovery at a median decoding coverage of 4.4 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $\times$\end{document} . In simulations, the reliability of our method has been verified on large data scales and diverse data formats. Section title: DISCUSSION Educational score: 3.116292715072632 Domain: biomedical Document type: Other Language: en The decoding results from wet experiments clearly reveal the presence of an acute cerebral infarction in the right frontal lobe of the patient in the medical images from November 2021 . In the medical images from October 2023, this cerebral infarction has evolved into a liquefied lesion, and a new acute cerebral infarction has appeared in the left cerebellar hemisphere . This highlights the significance of our scheme in storing medical images for disease screening and tracking. Section title: DISCUSSION Educational score: 3.928764820098877 Domain: biomedical Document type: Other Language: en The DNA palette code aligns with the spatial disorder of oligos, using unordered combinations of oligos as codewords. For binary input strings of the same length, the number of encoded oligos varies and does not require additional indexing. It performs well in both in vitro and in silico experiments and shows the potential to increase the information density and reduce decoding sequence coverage. The DNA palette code has the potential to expand new application scope for DNA data storage, offering robust support for historical trend analysis and retrospective studies. However, achieving the same high compression ratio as mature compression algorithms, such as the DEFLATE algorithm, presents a challenge for our encoder. This is an important direction for our next research. | Study | biomedical | en | 0.999997 |
PMC11697997 | Section title: Introduction Educational score: 3.906219720840454 Domain: biomedical Document type: Review Language: en Returning to sports after corrective surgery is a significant consideration in patients with adolescent idiopathic scoliosis (AIS). Despite the absence of standardized guidelines, current evidence indicates that patients can safely return to various sports, including those that require extreme spinal movements, without serious complications . On the other hand, there are reports that only 60% of AIS patients are able to return to sports at an equal or higher level of physical activity than before surgery; therefore, the actual situation is not clear . Adjacent segment disease (ASD) is a common complication in patients with long-term outcomes following spinal fusion surgery for AIS, with an incidence rate of approximately 26-32% . However, the new-onset spondylolysis after corrective fusion surgery for AIS is extremely rare . Section title: Introduction Educational score: 3.4782378673553467 Domain: biomedical Document type: Clinical case Language: en We report two cases of spondylolysis occurring in the caudal adjacent vertebrae of the lower instrumented vertebra (LIV) after posterior corrective fusion surgery for AIS (a 13-year-old girl and a 12-year-old girl). In both cases, no bony healing of the spondylolysis was observed. Here, we share our experience and consider the relationship between sports activity and lumbar spondylolysis after posterior corrective fusion surgery for AIS. Section title: Case presentation Educational score: 1.441061019897461 Domain: clinical Document type: Clinical case Language: en Case 1 first visited our institution in October 2019, and case 2 first visited our institution in February 2019; therefore, these cases were consecutive. Section title: Case presentation Educational score: 1.1937052011489868 Domain: clinical Document type: Clinical case Language: pt Case 1 Section title: Case presentation Educational score: 3.918478012084961 Domain: clinical Document type: Clinical case Language: en A 13-year-old girl was referred to our hospital with a chief complaint of right back and left lumbar prominence. She had no back pain or lower limb symptoms, and all neurological examinations were normal. There were no significant findings related to her growth or medical history, and she was a member of a swimming club in junior high school. Plain radiographs of the standing whole spine showed a 40° structural curve from T11 to L4 (32° in left side bending position) and a 31° non-structural curve from T5 to T11 (21° in right side bending position) . Computed tomography (CT) revealed no developmental abnormalities in the spinal structure, including lumbar spondylolysis. Therefore, the patient was diagnosed with AIS based on Lenke classification type 5C. She had not reached menarche, and Risser grade 2. Four months later, after orthotic bracing, plain radiographs of the whole spine showed that the T11 to L4 curve had progressed to 47°, and surgery was planned . The spino-pelvic parameters were the following: Pelvic incidence (PI): 65°, Pelvic tilt (PT): 19°, Sacral slope (SS): 44°, and Lumbar lordosis (LL): 55°. Section title: Case presentation Educational score: 3.927236557006836 Domain: clinical Document type: Clinical case Language: en Nine months after diagnosis, posterior corrective fusion surgery was performed from T5 to L3 . All dorsal laminae in the corrective fusion range were decorticated, and local bone obtained from the excision of the spinous processes and facet joints was grafted. The main thoracic curve at T5-T11 was non-structural, but the right-back prominence and low left shoulder were also the main complaints and were therefore deemed to be within the range of correction. The major lumbar curve from T11 to T4 was corrected to 9°, and the main thoracic curve from T5 to T11 to 5°. Postoperative spino-pelvic parameters were 66° for PI, 18° for PT, 46° for SS, and 67° for LL, indicating augmentation of lumbar lordosis. Preoperative and one week after surgery, CT scans show no abnormalities in the pars interarticularis (PI) of L4 . Section title: Case presentation Educational score: 3.3488738536834717 Domain: clinical Document type: Clinical case Language: en The postoperative course was uneventful, and the patient did not complain of lower back pain. She was instructed to wear a trunk orthosis for three months and to refrain from sports for six months after surgery. The patient was allowed to play sports from the seventh month after surgery, and she returned to swimming. Twenty-four months after the surgery, she joined her high school’s badminton club. She followed a routine of practicing for more than three hours on weekdays and participating in matches and tournaments on weekends. At 43 months after the operation (at age 17 years), she experienced severe lower back pain during a badminton match, which made it difficult for her to continue playing. She presented to our hospital, where CT revealed bilateral spondylolysis at the L4 . She was treated conservatively with cessation of sports activity, lumbosacral orthosis, and stretching was introduced to alleviate hamstring tightness. After three months of conservative therapy, CT was performed five months later to assess bony healing. Although bony healing of spondylolysis was not observed, the patient strongly desired a return to badminton competition. After returning to competition, she did not complain of lower back pain and could perform exercises at the pre-injury level. Twelve months after the onset of lumbar spondylolysis, the patient remained free of low back pain. We plan to conduct regular follow-up in the future. Section title: Case presentation Educational score: 1.036650538444519 Domain: clinical Document type: Clinical case Language: pt Case 2 Section title: Case presentation Educational score: 3.7982208728790283 Domain: clinical Document type: Clinical case Language: en A 12-year-old girl visited a doctor with a chief complaint of shoulder-height asymmetry. She had no back pain or lower limb symptoms, and all neurological examinations were normal. There were no significant findings in her growth or medical history, and she had not yet begun menstruation. She had been a badminton club member since the age of 11 years. Plain radiographs of the whole spine showed a 50° structural curve at T5 to T12 (47° in right side bending position) and a 27° structural curve at T1 to T5 (26° in left side bending position), and her condition was diagnosed as AIS of Lenke classification type 2 with Risser grade 0. Five months later, after orthotic bracing, plain radiographs of the whole spine showed that the T5 to T12 curve had progressed to 64°, and surgery was planned . The spino-pelvic parameters were the following: PI: 56°, PT: 14°, SS: 42°, and LL: 46°. Section title: Case presentation Educational score: 3.8323380947113037 Domain: clinical Document type: Clinical case Language: en Ten months after diagnosis, posterior correction and fusion surgery were performed from T3 to L2 . All dorsal lamina in the corrective range were decorticated, and local autogenous bone was grafted. The major thoracic curve from T5 to T12 was corrected to 9°, and the proximal thoracic curve from T1 to T5 to 15°. Postoperative spino-pelvic parameters were 58° for PI, 15° for PT, 43° for SS, and 51° for LL, indicating augmentation of lumbar lordosis. Preoperative and one week after surgery, CT scans show no abnormalities in the PI of L3 . Section title: Case presentation Educational score: 2.8908064365386963 Domain: clinical Document type: Clinical case Language: en The patient reported no postoperative back pain. She was instructed to wear a trunk orthosis for three months and to refrain from sports for six months after surgery. At the six-month follow-up examination, the patient complained of mild back pain; however, the radiographic examination revealed no obvious abnormalities. She was allowed to engage in sports from the seventh month after surgery. She joined a badminton club in junior high school and began to play. She occasionally experienced back pain that did not interfere with her daily life or sports activities. At a regular checkup 26 months after the surgery, the patient did not complain of back pain. She entered high school 27 months after the surgery and joined a badminton club. Compared with junior high school, the extent of badminton practice increased significantly, and the number of matches played during the weekend also increased. She practiced for three hours every weekday and played in matches every weekend. She experienced severe lower back pain immediately after a match 42 months after the operation (at age 17 years) and had difficulty moving. Section title: Case presentation Educational score: 2.448011875152588 Domain: clinical Document type: Clinical case Language: en The patient was treated with conservative therapy, such as medication and local injections, at a local clinic. As her lower back pain eased, she continued playing badminton without undergoing a thorough examination. At a regular checkup 50 months after surgery, plain radiography revealed suspected L3 spondylolysis. CT was performed, and the patient was diagnosed with bilateral L3 end-stage spondylolysis . As terminal spondylolysis was present, we did not expect bony healing to occur, and as the lower back pain resolved, no active treatment was performed. There were no further complaints of lower back pain, and the patient could resume badminton throughout high school. She retired from the sport after graduating from high school. The patient was scheduled for regular follow-ups. Section title: Discussion Educational score: 1.9290720224380493 Domain: biomedical Document type: Other Language: en Idiopathic scoliosis and spondylolysis in adolescence Section title: Discussion Educational score: 3.400426149368286 Domain: biomedical Document type: Study Language: en A significant number of patients with AIS have concomitant spondylolysis, with a prevalence of 7%. . However, to the best of our knowledge, there have been only three reports of new-onset spondylolysis or spondylolisthesis occurring after corrective surgery for scoliosis . Based on these reports, the two cases reported here are considered extremely rare. Table 1 shows a comparison of the background and course of development of lumbar spondylolysis in previous reports and the present cases. Section title: Discussion Educational score: 3.8619940280914307 Domain: biomedical Document type: Study Language: en In all previous cases, the LIV was L4 or L5, and spondylolysis occurred in L5 vertebrae. All of these cases were discussed as ASD caused by mechanical stress. However, since the L5 vertebrae are also commonly affected in ordinary spondylolysis and spondylolysis that occurs concomitantly with AIS, it is possible that there was a contribution from the anatomical characteristics of L5. In contrast, in the present cases, the injured vertebrae were L3 and L4, which were adjacent to the LIV, and the same mechanism as that of ASD after spinal fusion surgery was considered. Section title: Discussion Educational score: 1.6051443815231323 Domain: biomedical Document type: Other Language: en Return to sport after surgery for AIS and ASD Section title: Discussion Educational score: 4.139209747314453 Domain: biomedical Document type: Review Language: en AIS is the most common form of scoliosis, affecting approximately 2-4% of adolescents . Of these, approximately 10% require some form of treatment, and up to 0.1% undergo surgery . The goal of treatment is to prevent curve progression and improve cosmetic and functional outcomes. Surgical treatment of AIS has evolved significantly over the past two decades. Between 1997 and 2012, posterior fusion became the mainstay of treatment, with the rate of posterior fusion increasing from 63.4% to 94.1% . Recent studies have shown that adolescents can safely return to sports after surgery for AIS, and the use of modern instrumentation has enabled earlier resumption of activities . Most surgeons allow non-contact sports three months postoperatively, contact sports after six months, and collision sports after 12 months . However, a few reports suggest that the average time to return to sports is approximately eight months . Furthermore, there are also studies reporting a range of 6-18 months for return to sports activities . Factors affecting early return include being younger, having a higher Lenke type, and having lower main curve severity . Although many patients can resume their preoperative activities, some move on to low-impact sports because of reduced spinal mobility and flexibility . Despite the lack of established guidelines, current evidence suggests that patients can safely return to various sports, including those that require extreme spinal motion, without experiencing serious complications . Section title: Discussion Educational score: 3.8715336322784424 Domain: biomedical Document type: Study Language: en The incidence of ASD following spinal fusion surgery for AIS is approximately 26-32%. . The risk factors for ASD include a long follow-up period, fusion of 10 or more segments, and the extent of fusion, with the highest prevalence in East Asia . Age at the time of surgery and pre-existing disc degeneration were also significant risk factors . Most previous reports on ASD discussed disc degeneration in long-term postoperative cases, and reports on spondylolysis of the adjacent vertebrae are extremely rare . Section title: Discussion Educational score: 1.3958231210708618 Domain: biomedical Document type: Other Language: en Characteristics of the presented cases and learned precept Section title: Discussion Educational score: 4.282285690307617 Domain: biomedical Document type: Study Language: en Lumbar spondylolysis is a common condition in adolescent athletes, and its prevalence varies depending on the sport. The risk of spondylolysis differed by sex, with baseball, soccer, and hockey having the highest prevalence in males and gymnastics, marching band, and softball for female athletes . Although there are no reports that badminton is a risk factor for spondylolysis, it is an overhead sport that involves repeated extension and rotation of the lumbar spine, and it is thought to be a risk factor for acute and overuse disorders of the lower back in young elite players. Recent biomechanical research has shown that thoracic flexibility affects the stress on the lumbar intervertebral discs and PI. In other words, it is possible that in our cases, the decrease in thoracic flexibility due to spinal fusion increased the mechanical stress on the PI, leading to spondylolysis . In these two cases, the presence of a horizontal fracture line on the bilateral PI suggests that the cause of the spondylolysis was the stress of overextension rather than the rotational stress of the lumbar spine . In particular, in Case 1, the main thoracic curve was non-structural, which may have prevented the development of spondylolysis by reducing the thoracic fusion level and preserving thoracic mobility as much as possible. Furthermore, in both cases, a comparison of preoperative and postoperative spinopelvic parameters showed an increase in LL postoperatively. The increased LL is thought to be one of the causes of spondylolysis. The two cases we encountered were patients with AIS who had undergone posterior corrective fusion surgery and participated in high-level badminton competitions as members of organized teams. In addition to practicing for more than three hours on weekdays, they were exposed to high physical loads due to their participation in weekend matches and championships. Patients such as these commonly develop spondylolysis in the caudal adjacent vertebrae of the LIV. To prevent similar outcomes in the future, preserving the maximum possible number of mobile segments during corrective fusion should be considered in patients who strongly desire to return to high-level competitive sports. Particularly, the LIV should be set more cranially to preserve the mobile segment . In addition, because spinal flexibility decreases following surgery, transitioning to low-impact sports that do not involve rotational forces or excessive lumbar extension should be considered. Improving lower limb muscle tightness and strengthening the trunk muscles, especially the lower spinal extensor, are useful for postoperative AIS patients to return to sports . If lower back pain occurs during sports, it is important to visit a medical institution at the earliest for a thorough examination. It is especially advisable to consult a physician who performs scoliosis surgery. If a physician does not understand the pathophysiology, the diagnosis may be delayed. Although ASD is not an uncommon condition, it does not necessarily lead to clinical symptoms . In other words, long-term follow-up and regular screening are essential for the early detection and management of ASD, including spondylolysis. Section title: Conclusions Educational score: 3.9106147289276123 Domain: clinical Document type: Clinical case Language: en In this report, we present two cases of lumbar spondylolysis that occurred after corrective fusion surgery for AIS. Both patients participated in high-level badminton competitions postoperatively. Returning to sports after AIS remains a significant challenge, as high-level sports activities increase mechanical stress on the fixed adjacent segment, increasing the risk of developing lumbar spondylolysis. Sports activities involving rotational force or excessive lumbar extension should be approached cautiously. If a patient develops severe back pain after corrective fusion surgery for AIS, an early diagnosis by a specialist is necessary. | Review | biomedical | en | 0.999996 |
PMC11697999 | Section title: Introduction Educational score: 3.9523890018463135 Domain: biomedical Document type: Other Language: en Sump syndrome is a rare complication of biliary surgery, mainly choledochoduodenostomy (CDD) or choledochojejunostomy, that is now rarely seen in the Endoscopic Retrograde Cholangiopancreatography (ERCP) era, with a reported prevalence of between 0 - 9.6% . The CDD procedure may be performed when the common bile duct (CBD) drains improperly and has many indications, including strictures or obstruction of the bile duct and pancreas, biliary fistulas, recurrent bile duct stones, stenosis of the sphincter of Oddi, and choledochal cysts . Section title: Introduction Educational score: 4.108018398284912 Domain: biomedical Document type: Other Language: en Classically, in sump syndrome, the distal bile duct becomes obstructed after CDD, with the CBD segment between the anastomosis and the ampulla of Vater becoming a reservoir or sump. This likely occurs due to low filling pressure in the distal bile duct because the well-functioning anastomosis interferes with normal distal peristalsis and drainage. When debris accumulates in the sump, recurrent pain episodes, fever, cholangitis, pancreatitis, biliary obstruction, or hepatic abscesses may develop . Section title: Introduction Educational score: 2.852402925491333 Domain: clinical Document type: Clinical case Language: en We present the case of a 61-year-old female patient who exhibited clinical signs concerning for ascending cholangitis. Her detailed medical history, imaging studies, and ERCP led to the diagnosis of sump syndrome. This case was previously presented as a meeting abstract at the 2024 Michigan Chapter of the American College of Physicians Annual Scientific Meeting on October 26, 2024. Section title: Case presentation Educational score: 3.805997133255005 Domain: clinical Document type: Clinical case Language: en A 61-year-old female with a reported history of cholecystectomy, type 2 diabetes, and alcohol use disorder presented to the emergency department with two weeks of right-sided abdominal pain, nausea, and anorexia. She was hypertensive with right upper quadrant tenderness on physical exam. Her lab studies (Table 1 ) revealed elevated alkaline phosphatase (147 U/L) with otherwise normal transaminases, elevated lipase , total hyperbilirubinemia (1.6 mg/dL), leukocytosis with a left shift (WBC 17.9/L), hyperglycemia (596 mg/dL), high anion gap metabolic acidosis (venous pH 7.14, CO2 7 mmol/L, anion gap 31 mmol/L. A computed tomography (CT) scan of her abdomen with contrast showed abnormal appearing thick-walled proximal small bowel and a malrotated duodenum with surrounding inflammatory changes extending to the pancreas suspicious of fistulous communication to the bile ducts where there was extensive pneumobilia. She received fluids, ceftriaxone, metronidazole, and insulin and was transferred to our hospital. Section title: Case presentation Educational score: 3.8006746768951416 Domain: clinical Document type: Clinical case Language: en Her complete medical record was obtained following her arrival at our facility and revealed that she had undergone an open cholecystectomy and side-to-side choledochoduodenostomy two years prior. Magnetic resonance cholangiopancreatography (MRCP) demonstrated persistent extrahepatic biliary ductal dilation with a fistulous tract from the proximal CBD to the proximal duodenum and edema along the pancreatic bed, suggesting pancreatitis . Endoscopic retrograde cholangiopancreatography (ERCP) revealed an opening at the second part of the duodenum, appearing classic for a functioning choleduodenal anastomosis. The ampulla of Vater was consistent with a prior sphincterotomy; the CBD was cannulated without stenting, and fibrous food debris was extracted until no evidence of filling defects remained. The findings were consistent with the sump syndrome. The patient’s post-operative course was unremarkable, and she was discharged home in stable condition. Section title: Discussion Educational score: 3.921224355697632 Domain: biomedical Document type: Clinical case Language: en A sump is a pit or reservoir serving as a liquid drain or receptacle . In sump syndrome, a sump is formed as a complication of biliary bypass surgery, most commonly CDD, with an average timeframe to appear of 6 - 11 years postoperatively . The resulting anatomy after a CDD creates a potential space for sump syndrome to develop . The incidence of sump syndrome following a CDD is variable, with reported values ranging from 0 - 15.7% . This variation can be attributed partly to the length of time to presentation and the lack of a precise definition of the syndrome. Our patient presented two years after her CDD, making it an unusually early occurring case of sump syndrome. Section title: Discussion Educational score: 4.008777141571045 Domain: biomedical Document type: Other Language: en A combination of clinical and radiologic findings best characterizes the sump syndrome. Though not always present, clinical symptoms are often recurrent and include right upper quadrant pain, jaundice, fever, liver abscesses, pancreatitis, and signs of cholangitis. Ultrasound, CT, and MRCP are all imaging modalities that can suggest sump syndrome. Radiological signs of suspicion include debris or gallstones in the distal CBD and pneumobilia . Pneumobilia may indicate a functional anastomosis in a patient with an unknown surgical history. In a patient with a known history of CDD, this may be a normal finding. However, these radiographic findings warrant further investigation in conjunction with clinical symptoms or in a patient without detailed history. Section title: Discussion Educational score: 4.032479286193848 Domain: biomedical Document type: Study Language: en Despite clinical signs and symptoms indicative of sump syndrome, the diagnosis is confirmed with ERCP. Diagnosis and treatment may occur concomitantly because ERCP with sphincterotomy of the ampulla of Vater should be the first-line treatment in most instances of the syndrome . In a large retrospective cohort study of 70 patients with a history of CDD, Demirel et al. found that endoscopic sphincterotomy successfully diagnosed and definitively treated all 11 with sump syndrome . However, definitive surgery may be performed if endoscopic management fails or repeat intervention is required . Recurrence of the syndrome after endoscopic sphincterotomy is not uncommon, as indicated by Mavrogiannis et al. In a case series of 31 patients, nearly 20% experienced restenosis of the sphincterotomy opening . Surgical options are limited but include conversion to other biliary diversion options such as hepaticojejunostomy or distal gastrectomy with Roux-en-Y gastrojejunostomy . Section title: Conclusions Educational score: 3.827477216720581 Domain: biomedical Document type: Clinical case Language: en It is essential to consider sump syndrome in patients with cholangitis or pancreatitis who have a history of biliary surgical intervention, especially when their procedural details are unknown. The case presented affirms MRCP as a valuable diagnostic tool for sump syndrome and is notable as an early-occurring example of a typically late-presenting complication of CDD. Identifying the diagnosis of sump syndrome is critical for definitive treatment and avoiding future episodes of potentially life-threatening complications like cholangitis. | Other | biomedical | en | 0.999996 |
PMC11698019 | Section title: 1 Introduction Educational score: 4.300687789916992 Domain: biomedical Document type: Review Language: en In 2011, Ti 3 C 2 Tx was synthesized for the first time in the MXene family, attracting great attention since its first synthesis. MXene is characterized by atomic layers with sandwich-like layered morphology . Due to its high conductivity, high hydrophilicity and large specific surface area, MXene is widely used in various research fields such as energy storage, wireless communications, and biomedical applications. In the field of biomedical applications, MXene has been widely used in bioimaging, biosensors, photothermal therapies, drug delivery and antimicrobial drugs . To determine whether MXene-based biomaterials are biocompatible, they must be tested for biocompatibility in general biomedical applications. Recent developments in MXene-infused biomaterials with desirable physicochemical properties have been observed. A study by Lin et al. has found that electroactive MXene hydrogels can accelerate the healing process of skin wounds by coupling ES (Electrical Stimulation) with MXene . In a study by Ye et al., conductive Ti 2c-frozen gel enhanced cardiomyocyte function and myocardial infarction repai . Hu et al. prepared electroactive hydrogels by MXene and regenerated filament factor (RSF) to promote effective bone regeneration, and demonstrated that MXene/RSF hydrogels provide a unique and promising strategy for promoting direct bone formation, regulating the immune microenvironment, and neovasculation under ES. In their study, Yu et al. developed a novel polyvinylpyrrolidone/phytic acid/MXene hydrogel which is biocompatible and can be used for SCI repair. In a rat model of complete spinal cord amputation, hydrogels significantly accelerated spinal cord regeneration by accelerating angiogenesis, myelin regeneration, axon regeneration, and calcium channel activation . Researchers Yang et al. developed a diabetic wound healing injectable hydrogel that combined hyaluronic acid-graft-dopamine (HA-DA) and polydopamine (PDA) . Section title: 1 Introduction Educational score: 4.260565280914307 Domain: biomedical Document type: Study Language: en The electrospinning process is a general approach to preparing polymer fiber scaffolds ranging from microns to nanometers in diameter. These fibrous scaffolds mimic the natural extracellular matrix, and they are used to develop tissues, deliver drugs, coat scaffolds with polymers, and so forth in biomedical applications. There are several types of polymers that can be used in the production of nanofibers, including polycaprolactone (PCL), polylactic acid (PLA), polyglycolic acid (PGA), cellulose, chitosan, gelatin and silk fibroin (SF) . SF, as a natural fibrin, has become a promising polymer biomaterial for tissue engineering due to its extensive molecular structure, remarkable mechanical properties, controllable morphology, multifunctional processing capabilities, and surface modification options . The silk fibers of Bombyx mori are composed of silk fibroin (SF) coated with silk sericin (SS). The degummed silk obtained after boiling and degumming is silk fibroin . Electrospun SF fibers exhibit high surface area-to-volume ratios, high porosity, and high flexibility, which are highly desirable for biomedical and tissue regeneration applications. In the earlier studies, hydroxyapatite mineralized silk fibroin was synthesized from reclaimed silk fibroin and tussah silk fibroin for bone tissue engineering. In this study, it was found that silk fibroin composite scaffolds were biocompatible and conducive to cell attachment and growth . In a study on fibroin membrane by Liu et al. , it was found that fibroin membrane is an excellent biomaterial with good cellular compatibility and provides a framework for post-trauma repair in clinical applications. Section title: 1 Introduction Educational score: 3.929860830307007 Domain: biomedical Document type: Study Language: en At present, electrospinning technology in addition to the preparation of single-component nanofibers, composite electrospinning nanofibers can also be modified by introducing different components to obtain the required physical, chemical and biological properties . Adding other fillers to composite nanofibers, such as in situ and ex-situ methods. Nanofiber composites are synthesized in situ by combining precursors of fillers with polymer solutions. A difference between in situ and ex-situ methods is that ex-situ methods mix the pre-synthesized particles directly into the polymer before electrospinning . Section title: 1 Introduction Educational score: 4.083849906921387 Domain: biomedical Document type: Study Language: en By mixing different polymers with different fillers, such as carbon-containing materials (such as graphene, carbon nanotubes), nanoparticles (such as polymers and metals), biomedical materials have enhanced electrical, chemical, mechanical, and thermal properties . Additionally, MXene has recently been used to modify the surface of electrospun nanofibers for biomedical applications . As a coating nanomaterial for PLLA nanofibers, Zhu et al. proposed Ti 3 C 2 Tx MXene as a nanomaterial that provides a surface that is rich in functional groups, hydrophilic and rough, thereby supporting the adhesion and proliferation of NSCs. In this study, the MXene coating significantly increased NSC differentiation into neurons and astrocytes, providing PLLA nanofibers with multiple advantages, improving nerve regeneration in a synergistic manner . Section title: 1 Introduction Educational score: 4.082640171051025 Domain: biomedical Document type: Study Language: en We therefore prepared SF-MXene composite fibers by electrospinning technology using an ex-situ method in this study. A physicochemical and biological evaluation of synthetic composite fibers was performed to understand the potential of two-dimensional materials in biomedicine. Regenerative medicine and tissue engineering will greatly benefit in the future from the properties required for composite electrospun fiber reinforcement materials (such as hydrophilicity, mechanical properties, degradability, protein absorption, biomineralization, and cell viability) ( Scheme 1 ). Section title: 2.1 Materials Educational score: 1.579293131828308 Domain: biomedical Document type: Study Language: en Ti 3 C 2 Tx MXene multilayer clay-like materials were purchased from XinXi Nanomaterial Technology Co., LTD. (Guangzhou China). Bombyx mori was obtained from cannongjidi (Zhejiang, China). Formic acid (CH2O2, ≥99.5%) was purchased from Aladdin (Shanghai China). Mouse embryonic fibroblast (L929) and pre-osteoblastic cell (MC-3T3) cell lines were purchased from Boya Bio (Guangzhou, China). Simulated body fluid, Cell Counting Kit-8 (CCK-8), AM/PI dual staining kit, Dulbecco’s modified Eagle’s medium (DMEM) were purchased from Solarbio Science and Technology Co., Ltd. (Beijing, China). Bovine serum albumin (BSA), and BCA protein assay kit were purchased from Nanjing KeyGen Biotech Co., Ltd. (Nanjing, China). All chemicals and solvents were of analytical grade and used without further purification. Section title: 2.2 Preparation of SF Educational score: 4.207534313201904 Domain: biomedical Document type: Study Language: en The bombyx mori cocoons were cut into small pieces and immersed in 0.02 M Na2CO3 aqueous solution, followed by heating at 100°C for 30 min with continuous stirring to degum the cocoons. The degummed bombyx mori cocoons were then washed with deionized water 4-5 times to remove residual sericin on the surface and dried in a 60°C oven. The degummed silk fibers were then dissolved in a pre-prepared 9.3 M LiBr aqueous solution and stirred vigorously at 60°C to form a pale yellow solution. A semi-permeable membrane (12 kDa MWCO) was used to dialyze the pale yellow sericin-LiBr solution against deionized water at room temperature for 72 h to remove excess LiBr salt. The dialyzed solution was centrifuged at 6,000 rpm for 10 min to remove residual impurities. The sericin solution was frozen overnight at −80°C and freeze-dried to completely remove solid water, yielding a white solid sericin powder that was stored at −20°C for future use. Section title: 2.3 Fabrication o of electrospinning solutions Educational score: 3.9365901947021484 Domain: biomedical Document type: Study Language: en MXene of different quality was added to formic acid solution to obtain MXene of different mass fraction. After ultrasonic dispersion for 12 h, multi-layer clay Ti 3 C 2 Tx MXene was stratified into less/single layer until it was well dispersed in formic acid solution. SF (15 wt%) was then added to each prepared MXene dispersion and magnetically stirred overnight until the solution was mixed. The mass fractions of MXene in each solution were (0.1, 0.5 and 1 wt%). The other group prepared a pure SF solution by adding only SF (15 wt%) to the formic acid and slowly stirring it overnight. Section title: 2.4 Fabrication of SF-MXene composite electrospun fibers Educational score: 4.11991024017334 Domain: biomedical Document type: Study Language: en The prepared electrospinning solution was sucked into a 5 mL plastic syringe using a metal capillary tube (diameter = 0.51 mm) as a needle. The high voltage power supply (Dongwen Co., LTD., Tianjin) provides 21 kV voltage and is connected to the metal needle. The syringe is connected using a digital injection pump (Ximai Technology Co., Nanjing), and the solution is set at 0.5 mL/h. The distance between the needle and the drum collector with aluminum foil on the surface (Qingdao Nuokang Technology Co., LTD., Qingdao) is 10 cm. The speed of the drum was set to 1500 rpm/min. The prepared electrospinning film was placed in anhydrous ethanol for 10 min, then washed with pure water at 37°C and dried at room temperature. The nanofiber membranes prepared with different Ti 3 C 2 Tx MXene content solutions were labeled as SF, SFM0.1, SFM0.5 and SFM1, respectively. Section title: 2.5 Physicochemical characterizations Educational score: 4.1251444816589355 Domain: biomedical Document type: Study Language: en The surface morphology of the electrospun fibers was observed by field emission scanning electron microscopy . Fiber diameters were measured using ImageJ software (NIH, United States). The elemental composition of the electrospun fibers was confirmed by mapping with FESEM integration. Fourier transform infrared spectroscopy (FTIR; Thermo Scientific Nicolet iS20, United States), X-ray diffractometer (XRD; Panalytical Empyrean, Netherlands), has analyzed the chemical properties and crystal structure of the matrix. The hydrophobicity of electrospun fibers was measured using a contact Angle analyzer (JY-82C, China). Thermogravimetric analysis (TA Discovery TGA 550, United States) was performed at 10°C/min at 30–600°C under a nitrogen atmosphere. The mechanical strength of the nanofiber membrane was tested at a tensile speed of 5 mm/min using a universal material testing machine (MTS, China). Section title: 2.6 Determination of degradation rate of electrospun nanofibers Educational score: 4.109928131103516 Domain: biomedical Document type: Study Language: en To investigate the in vitro degradation rate of electrospun nanofibers, samples were immersed in PBS (PH = 7.0) for 14 days at 37°C. After different time points (0, 1, 3, 5, 7, 14 days), samples were collected from PBS and excess water was removed. The weight was recorded as Wd and compared with its original weight (Wo). The rate of degradation was calculated using the following equation: Degradation rate = Wo − Wd / Wo × 100 % Section title: 2.7 Protein adsorption capacity Educational score: 4.102420330047607 Domain: biomedical Document type: Study Language: en For the purpose of determining the synthetic nanomaterial’s adsorption efficiency, bovine serum albumin (BSA) was used as a model protein. The fiber film, cut into a 10 mm diameter circle, was placed in a test tube and incubated with 15 mL of BSA solution (2 mg/mL) at 300 rpm for 24 h. The protein concentration in the sample was measured using the BCA (bicinchoninic acid) assay, which specifically quantifies protein levels based on the colorimetric reaction between BCA reagent and proteins. The concentration of adsorbed BSA was determined by measuring the absorbance at 562 nm. Section title: 2.7 Protein adsorption capacity Educational score: 4.066739082336426 Domain: biomedical Document type: Study Language: en The protein concentration was calculated using the following formula: Protein concentration μ g / mL = A determination − A blank / × A standard − A blank * C standard where A determination is the absorbance of the sample, A blank is the absorbance of the blank solution, A standard is the absorbance of the BSA standard, C Standard: Standard concentration, 524 μg/mL. Section title: 2.8 Biomineralization test Educational score: 4.117005348205566 Domain: biomedical Document type: Study Language: en For the purpose of studying the effects of 2D MXene on SF fiber surfaces, biomimetic mineralization tests were conducted on electrospun fibers incubated with SBF. Electrospun SF and SF-MXene composite electrospun fiber pads were incubated in 5 mL SBF solution at 37°C. The fresh SBF solution is replaced every 24 h during the culture process. After incubation for 2 weeks, the sample was removed from the SBF and washed with deionized water. A FESEM analysis is conducted on the samples obtained at room temperature after they have been dried. Section title: 2.9 Biocompatibility assay Educational score: 4.131495475769043 Domain: biomedical Document type: Study Language: en In order to perform the experiment, the electrospun fiber pad was sterilized in the microwave for 20 min and then transferred to a 24-well plate under ultraviolet light for 12 h. Sterile samples were rinsed with phosphate-buffered saline (pH 7.4) and co-cultured with fibroblasts/osteoblasts in DMEM.2 × 104 cell and 1,000 μL medium were co-cultured with electrospinning fiber membrane of each group, and incubated at 37°C and 5% CO2. Change the medium every 1-2 days. Three parallel control groups were set up for each sample. Incubate in the incubator according to preset time nodes (1d, 2d, 3d). According to the operation method of the CCK-8 kit, 100μLCCK-8 solution and 900 μL medium were added to each well, and incubated at 37°C for 2 h away from light. The absorbance was then measured at 450 nm using an enzyme-labeler. Cell viability is calculated by the following formula: cell viability % = measured value − blank value / × control value − blank value × 100 % Section title: 2.9 Biocompatibility assay Educational score: 4.151473522186279 Domain: biomedical Document type: Study Language: en After the cells were incubated with the fibromembrane for 3 days, live and dead cells were labeled using a fluorescence-based live/dead cell toxicity kit according to the manufacturer’s protocol to assess cell viability. A 20-min incubation in the dark was performed on cells co-cultured with the membrane. An inverted fluorescence microscope (Nikon, Japan) was used to image staining samples after washing the cells with PBS. A software application called ImageJ was used to detect and count live cells (green fluorescence) and dead cells (red fluorescence). Cell viability is calculated using the following formula: cell viability % = number of live cells / × number of live cells + number of dead cells × 100 % Section title: 2.10 Alkaline phosphatase (ALP) activity Educational score: 4.112286567687988 Domain: biomedical Document type: Study Language: en Pre-osteoblasts (MC3T3-E1) were seeded on each electrospun fiber membrane, and alkaline phosphatase (ALP) activity was detected by alkaline phosphatase staining kit after 7 days of culture. Briefly, the medium from each well was carefully removed and the cells were washed three times with PBS. Then, BCIP/NBT staining solution was added and incubated at room temperature for 2 h, and the color reaction was terminated by washing once with distilled water. Alkaline phosphatase activity was semiquantitatively analyzed using ImageJ software (NIH, United States). Section title: 2.11 Statistical analysis Educational score: 3.127765417098999 Domain: biomedical Document type: Study Language: en Three parallel trials were performed for each experiment, and all data are reported as mean ± SD. All experimental results were compared using one-way ANOVA, and the data were statistically analyzed using GraphPad Prism 8.0 software. A statistical difference of P < 0.05 was considered significant. (*P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.001) Section title: 3.1 Physiochemical properties Educational score: 3.3344533443450928 Domain: biomedical Document type: Study Language: en Few/single-layer MXene nanosheets were obtained by ultrasonically exfoliating clay-like multilayer Ti 3 C 2 Tx MXene. Scanning electron microscope (SEM) images of the multilayer Ti 3 C 2 Tx MXene showed a distinct multilayer nanosheet structure . After 12 h of ultrasonic dispersion, the nanosheets exhibited an obvious few/single-layer structure under the SEM . Section title: 3.1 Physiochemical properties Educational score: 4.167529582977295 Domain: biomedical Document type: Study Language: en The surface morphologies of SF and SF-MXene composite electrospun fibers doped with different weight percentages of Ti 3 C 2 Tx MXene are shown in Figures 2A–D . As the content of Ti 3 C 2 Tx MXene increased, the fiber morphology of the composite fibers did not change significantly. Compared with SF fibers, the diameter of the composite fibers decreased after the incorporation of Ti3C2Tx MXene, and as the MXene content increased, the diameter gradually decreased. The histograms of fiber diameters for each group are shown in Figures 2E, F . The average fiber diameter decreased with increasing MXene content: SF fibers had a diameter of 0.105 ± 0.02 μm, 0.1 wt% MXene was 0.097 ± 0.02 μm, 0.5 wt% MXene was 0.071 ± 0.01 μm, and 1 wt% MXene was 0.068 ± 0.02 μm. Statistical analysis using ANOVA was performed to evaluate the significance of these changes. The results showed that the fiber diameter significantly decreased with increasing MXene content, with p-values of <0.0001, indicating a statistically significant difference between the groups. This change is likely due to the inherent conductivity of MXene, which increases the conductivity of the spinning solution, leading to a more pronounced stretching of the Taylor cone under the same electric field strength. After doping, the fiber surface remained smooth. In addition, the presence of Ti elements in the SF-MXene composite fibers was confirmed by SEM-EDS, indicating that Ti 3 C 2 Tx MXene had been incorporated into the fibers, as shown in Figure 3 . Section title: 3.1 Physiochemical properties Educational score: 4.465494155883789 Domain: biomedical Document type: Study Language: en As shown in the FTIR spectra , the SF fibers exhibit distinct absorption peaks at 3,288 cm^-1, 2,986 cm^-1, 1,645 cm^-1, 1,516 cm^-1, 1,233 cm^-1, 1,168 cm^-1, 1,055 cm^-1, and 542 cm^-1. The broad peak at 3,288 cm^-1 corresponds to the O-H stretching vibration in silk fibroin. The absorption peak at 2,986 cm^-1 is attributed to the C-H stretching vibration. The absorption peaks at 1,645 cm^-1, 1,516 cm^-1, and 1,233 cm^-1 are characteristic bands of amide I, amide II, and amide III of the protein in silk fibroin, respectively. The peaks at 1,168 cm^-1 and 1,055 cm^-1 are due to the C-OH and C-O stretching vibrations. These characteristic absorption peaks are consistent with the typical structure of silk fibroin . The presence of a prominent broad absorption band at 3,400 cm −1 in MXene indicates strong external water absorption on its surface . In SF-MXene composite electrospun fibers, the peak intensities at 542 cm -1 and 3,288 cm -1 are reduced. This attenuation is attributed to the formation of hydrogen bonds between MXene and silk fibroin molecules, which weakens the stretching vibrations of C-N and O-H bonds. The narrowing and reduced intensity of the characteristic peak at 1,645 cm -1 suggest that the incorporation of MXene destabilizes the β-sheet structure, leading to a transition towards an α-helix structure. Section title: 3.1 Physiochemical properties Educational score: 4.284861087799072 Domain: biomedical Document type: Study Language: en We further conducted XRD tests on various nanofiber groups, as shown in Figure 4B . Previous studies on silk fibroin (SF) have indicated that the main diffraction peaks of silk fibroin I structure appear at 12.2°, 19.7°, 24.7°, and 28.2°, while those of silk fibroin II structure are located at 9.1°, 18.9°, 20.7°, and 24.3° . In this study, the XRD curve of the silk fibroin membrane exhibited typical peaks at 19.7°, 20.7°, 24.7°, and 28.2°, providing strong evidence for the presence of silk fibroin I structure along with a small amount of silk fibroin II structure. As the Ti 3 C 2 Tx MXene content increased, the diffraction peak at 26.6°in the composite fiber XRD curve became more prominent. This might suggest that the introduction of Ti 3 C 2 Tx MXene altered the crystal structure of the composite material. MXene possesses abundant surface functional groups (such as -OH and -F), which could interact with amino or carbonyl groups in silk fibroin through hydrogen bonding or electrostatic interactions, enhancing the hydrophilicity and structural stability of the composite material and thus inducing changes in the structure of silk fibroin. This structural change might lead to a transition from a β-sheet structure to an α-helix structure, manifested as an enhancement associated with the 26.6°peak in the XRD pattern. Additionally, with increasing Ti 3 C 2 Tx MXene content, the diffraction peak at 17.6°in the silk fibroin-MXene (SFM) curve gradually decreased. This phenomenon could be attributed to the overlap of the characteristic peak of Ti 3 C 2 Tx MXene at 14.5°(004) with silk fibroin, resulting in a left shift of the peak position. This shift indicates an increase in the unit cell constant, suggesting the successful incorporation of Ti 3 C 2 Tx MXene into the silk fibroin structure, which may have led to microscopic adjustments in the structure of the composite material. Section title: 3.1 Physiochemical properties Educational score: 4.21026086807251 Domain: biomedical Document type: Study Language: en Thermogravimetric analysis (TGA) was performed on SF and SF-MXene composites, and the corresponding TGA curves are presented in Figure 4C . Both SF and SF-MXene composite fibers exhibited two distinct stages of mass loss during thermal degradation. The first stage was attributed to the loss of moisture from the fiber membranes. The second stage, occurring between 270°C–330°C, corresponded to the degradation of SF itself. This mass loss was due to the decomposition of SF polymer chains, primarily through the loss of volatile components such as small molecules and degradation products. Interestingly, as the weight percentage of Ti3C2Tx MXene increased, the residual mass of the composite fibers also increased. This suggests that MXene enhances the thermal stability of SF fibers, which may be related to the high thermal conductivity and stability of MXene nanoparticles. The increased residual mass confirms the successful incorporation of MXene into SF fiber membranes at different weight percentages . The presence of MXene particles serves as a thermal stabilizer, reducing the overall mass loss during thermal degradation. Section title: 3.1 Physiochemical properties Educational score: 4.302437782287598 Domain: biomedical Document type: Study Language: en The hydrophilicity of materials plays a crucial role in their interaction with cells, as it directly affects the material’s ability to adsorb proteins and interact with the biological environment. To evaluate whether the addition of MXene nanoparticles improves the hydrophilicity of composite electrospun fibers, we measured the water contact angle (WCA), as shown in Figure 5 . The pure SF fibers exhibited a contact angle of 113.36° ± 2.84°, indicating their hydrophobic nature. However, with increasing proportions of Ti3C2Tx MXene, the wettability of the composite fibers improved, evidenced by a gradual decrease in the contact angle: SFM0.1 had a contact angle of 95.57° ± 3.63°, SFM0.5 showed 91.27° ± 1.83°, and SFM1 demonstrated 85.27° ± 3.16°.The enhanced wettability with increasing MXene content can be attributed not only to the hydrophilicity of hydroxyl and oxygen-containing functional groups on the MXene surface but also to the increased surface roughness and porosity of the electrospun fibers. As the MXene content increases, the fiber diameter decreases, leading to an increased specific surface area of the fiber mat. This increase in specific surface area creates more contact points between the fiber mat and water molecules, thereby improving its wettability. Furthermore, the increased porosity aids in capillary action, allowing the fibers to absorb water more effectively, further enhancing their hydrophilicity. Thus, the increased MXene content improves not only the surface chemical properties of the fibers but also their physical structure, both of which contribute to the observed enhancement in wettability and hydrophilicity. Section title: 3.1 Physiochemical properties Educational score: 4.106143951416016 Domain: biomedical Document type: Study Language: en Good mechanical properties have better stability and ductility, which can play a better role in biological tissue engineering. To elucidate the effect of adding Ti 3 C 2 Tx MXene on the mechanical properties of the scaffolds, the tensile strength of various nanofibrous scaffolds was measured. Figure 6 shows the stress-strain curves of composite fibers without and with 0.1wt%, 0.5wt%, and 1wt% MXene. With the increase of MXene content, the mechanical strength of composite fiber at 0.5wt% and 1wt% was significantly higher than that of pure SF and 0.1wt%. This may be due to the interaction between MXene surface rich oxides or fluorides and a large number of amino acid residues in SF, especially hydroxyl groups and amino groups, through hydrogen bonding. Thus, the mechanical properties of the composite fibers are improved. Section title: 3.2 Degradation rate of electrospun nanofibers Educational score: 4.128568649291992 Domain: biomedical Document type: Study Language: en The degradation performance of biomaterials is also one of the important characteristics of their applications, and excellent degradation performance will be conducive to their wider application in more scenarios. In this study, we investigated the degradation properties of SF and electrospun fiber membranes with different contents of Ti 3 C 2 Tx MXene within 2 weeks. As shown in Figure 7 , panel A shows the degradation rate of each group’s fibrous membrane at different time points within 14 days, and panel B shows the degradation rate of each group’s fibrous membrane at 14 days. As can be seen from the degradation curve in FIG. A, the degradation rate of all samples reached the maximum at 5–7 days and tended to be flat at about 14 days. The results of panel B show that the degradation rate of the samples with high content of MXene addition (0.5wt% and 1wt%) is significantly lower than that of the samples with low content of mxene addition (0wt% and 0.5wt%). This may be due to the introduction of mxene nanoparticles, the fiber structure becomes compact due to hydrogen bonding, electrostatic interaction and other forces, the mechanical strength increases, and the degradation rate phase is relatively slow. Section title: 3.3 Protein adsorption capacity Educational score: 4.153504371643066 Domain: biomedical Document type: Study Language: en Bovine serum albumin (BSA) was used as a model protein to test the protein adsorption capacity of different materials. Figure 8 shows the amount of protein adsorbed by each group of materials over 24 h. The results showed that the protein adsorption rate of each nanofiber membrane group was significantly higher than that of the control group, indicating that both SF and MXene promoted the adsorption of proteins. With the addition of mxene nanoparticles, the protein adsorption rate of SF-MXene composite fiber materials also increased, and the protein adsorption rate of SFM1 group was significantly higher than that of SF and SFM0.1 groups. This outcome is likely due to the addition of Ti 3 C 2 Tx MXene, which provides various functional groups that offer more active binding sites for protein adhesion. The increased binding capacity of the fiber membranes for proteins is enhanced through electrostatic interactions, hydrogen bonding, and π-π interactions. Studies have shown that cell surfaces have numerous receptors that interact with proteins, which play a crucial role in the cellular response process . The excellent protein adsorption capability of the material allows for the rapid formation of a protein layer on its surface, providing more binding sites and thus enhancing cell adhesion and migration. Therefore, the increased protein adsorption capacity of the material significantly enhances its bioactivity. Our study results demonstrate that incorporating Ti 3 C 2 Tx MXene can significantly improve the protein binding ability of SF. This characteristic can also effectively facilitate the binding of scaffold materials with osteoinductive factors such as growth factors and drugs, thereby increasing the material’s application value. Section title: 3.4 Biomineralization Educational score: 4.195858001708984 Domain: biomedical Document type: Study Language: en The mineralization capability of SF-MXene composite fibers was evaluated using an in vitro biomineralization assay. SF fibers are well-known matrices for tissue engineering due to their good biocompatibility; it has not yet been evaluated whether composites containing Ti 3 C 2 Tx MXene mineralize. Therefore, the study investigated SF-MXene composites to evaluate their ability to adsorb calcium phosphate minerals in SBF solution. After 14 days of soaking in SBF solution, FESEM images of electrospun SF and SF-MXene composite electrospun fibers are shown in Figure 9 . As expected, the SF-MXene composite fibers successfully deposited calcium phosphate minerals . The deposition of calcium and phosphate ions on the electrospun fiber membrane may be due to the high hydrophilicity of MXene . In contrast, no significant calcium phosphate mineral deposition was observed on the pure SF electrospun fibers after 14 days of soaking in SBF solution . Further confirmation of the presence of calcium and phosphorus in the SBF-treated SF-MXene fiber scaffolds was obtained through EDS analysis. The results demonstrated that the substantial in vitro biomineralization and calcium/phosphorus deposition on the SF-MXene composite scaffolds endowed them with sufficient bioactivity, indicating their potential for further application in bone tissue engineering. Section title: 3.5 Biocompatibility Educational score: 4.132760047912598 Domain: biomedical Document type: Study Language: en To determine how SF-MXene composite electrostatic spinning fibers respond to cells, fibroblasts (L929) and pre-osteoblasts (MC3T3-E1) were co-cultured with different electrospun fibers for 1, 2, and 3 days. The biocompatibility of the fiber scaffolds was assessed using the CCK-8 assay and live/dead cell staining. Cells seeded without fiber membranes served as the control group. Figure 10A shows the viability of L929 cells cultured on the electrospun fiber scaffolds for 1, 2, and 3 days. The viability of L929 cells on both SF and SF-MXene composite fibers remained at a high level. Figure 10B shows the cell viability of pre-osteoblasts (MC3T3-E1) cultured on electrospun fibers on the same days. For MC3T3-E1 cells, the viability on both SF and SF-MXene composite fibers with different MXene contents also remained at a high level. Figure 10C shows live/dead cell staining on the third day to determine the viability of L929 and MC3T3-E1 cells on different electrospun fiber membranes. The images from the live/dead staining were analyzed with ImageJ software to determine the ratio of red to green fluorescence, which was used to assess the cell viability on each group of fiber membranes. Figures 10D, E further indicate that the nanofiber electrospun membranes did not exhibit cytotoxicity to L929 cells, as all groups maintained high cell viability. This finding is consistent with the previous CCK-8 assay results. Section title: 3.6 Alkaline phosphatase (ALP) activity Educational score: 4.134096145629883 Domain: biomedical Document type: Study Language: en Alkaline phosphatase (ALP) is crucial in bone formation and mineral deposition; thus, assessing ALP staining intensity can provide an indirect measure of cellular mineralization capability and mineral deposition. In this study, the ALP activity was examined by culturing MC3T3-E1 cells on nanofiber membranes with varying amounts of MXene, followed by ALP staining after 7 days of culture. As illustrated in Figure 11A , cells cultured on pure SF exhibited lower ALP intensity, while increasing MXene content led to a marked enhancement in ALP staining intensity , with the highest intensity observed at 1 wt% MXene content. Semi-quantitative analysis of the stained images confirmed that higher MXene content significantly elevated ALP activity, suggesting that MXene promotes early osteoblast differentiation and enhances cellular mineralization and mineral deposition . Section title: 4 Conclusion Educational score: 4.314945697784424 Domain: biomedical Document type: Study Language: en In this study, we successfully demonstrated the electrospinning of silk fibroin (SF)-MXene composite fibers. The obtained electrospun fibers were characterized for their physicochemical properties and in vitro biocompatibility. Our results indicate that both SF fibers and SF-MXene composite fibers exhibit excellent biocompatibility with L929 and MC3T3 cells, underscoring their potential for biomedical applications. Compared to pure SF fiber membranes, the SF-MXene composite fibers displayed notable improvements in wettability, mechanical properties, biomineralization, and protein adsorption. These enhancements not only improve the fibers’ biocompatibility but may also broaden their applicability in tissue engineering and regenerative medicine. We attribute the unique properties of SF-MXene composite fibers to the abundance of active hydrophilic groups on the MXene surface, which bind effectively to the amino acid residues on the SF surface. Furthermore, MXene itself possesses valuable properties, including hydrophilicity, non-toxicity, and the ability to promote cell proliferation and biomineralization. These composite electrospun fibers show promise for biomedical applications such as wound dressings and bone tissue engineering. Additionally, the approach presented here provides a theoretical basis for the development of MXene-based polymer fiber composites, supporting future applications in tissue regeneration engineering. | Review | biomedical | en | 0.999998 |
PMC11698196 | Section title: Introduction Educational score: 2.835667371749878 Domain: biomedical Document type: Study Language: en Sugarcane ( Saccharum spp.) is among the most important economic and commercial crops in tropical and subtropical regions of the world . The mosaic caused by the Sugarcane mosaic virus (SCMV) is one of the most devastating diseases of sugarcane, not only significantly affecting sugarcane productivity but also interfering with the production of maize, sorghum, Canna , and other gramineous species worldwide . Incidences of SCMV have been reported in at least 70 countries . According to a recent study, SCMV has spread throughout sugarcane plantations in Pakistan, with a 7.01% incidence rate and a 20% decline in sugar production . Section title: Introduction Educational score: 4.157497406005859 Domain: biomedical Document type: Study Language: en The SCMV genomic is around 10 kb in size and is a single-stranded positive sense RNA . The polyprotein produced by SCMV was cleaved, co- and posttranslationally, into its component gene products, including the coat protein (CP) gene, by viral coded proteases . Since the CP is predominantly conserved among SCMV isolates, serological methods can be used to detect the virus . Section title: Introduction Educational score: 2.5152854919433594 Domain: biomedical Document type: Other Language: en Plant viruses have been widely detected using numerous immunodiagnostic techniques as well as molecular techniques . Generally, molecular approaches for viral detection are not appropriate for large-scale sample indexing as routine tests since they are more expensive, and the technique is more complicated than serology-based detection . Section title: Introduction Educational score: 3.9125607013702393 Domain: biomedical Document type: Study Language: en Traditionally, a polyclonal antibody is developed using a pure virion from infected plant material for immunodiagnostics . However, the traditional approach to producing polyclonal antibodies has two drawbacks: the minimum viral concentration in the infected plant tissue and the purity of the virion. The process of propagating a virus in an appropriate host and purifying it is laborious . Moreover, certain viruses, such as potyvirus and phloem-limited luteoviruses, are particularly difficult since they have low viral concentrations. Section title: Introduction Educational score: 4.131996154785156 Domain: biomedical Document type: Study Language: en In the present study, we utilized in silico methods to enhance the development of a diagnostic tool for SCMV detection. Computational analyses, including examination of the physicochemical properties, immunogenicity, and subcellular localization of the SCMV CP, were used to predict the protein’s behavior and optimize its antigenic properties . These in silico approaches provide valuable insights that guide the design of recombinant proteins and improve the sensitivity and specificity of immunodiagnostic assays. By integrating in silico predictions with experimental validation, we aim to develop a rapid and reliable diagnostic tool for SCMV. This approach not only enhances the accuracy of SCMV detection but also reduces the time and resources required for diagnostic procedures, offering a significant advancement over traditional methods . Section title: Introduction Educational score: 4.115208625793457 Domain: biomedical Document type: Review Language: en Recombinant CP-based antibodies have been utilized extensively in immunodiagnostics to address the problem. Recombinant CPs have been used in several investigations as antigens to produce polyclonal antibodies, including Cucumber mosaic virus , Citrus psoriasis virus , Sugarcane mosaic virus , and Onion yellow dwarf virus . According to a recent report , CP-based antisera can detect viruses in symptomless primary and secondary hosts. Although the application of CP-based antisera for virus detection in symptomless plants may not constitute a novel approach, it is important to take into account that this method has a rich history in scientific research. For decades, researchers have relied on antisera specifically designed to target the CP of purified virus particles. This long-standing tradition highlights the enduring effectiveness and practicality of CP-based antisera in the field of virus detection; thus, serological detection is an easy, quick, and affordable technique suitable for virus identification. Therefore, crop damage can be reduced, and customized treatments can be used to tackle the pathogens. Section title: Introduction Educational score: 4.070427894592285 Domain: biomedical Document type: Study Language: en In the present study, the CP gene of an SCMV isolate infecting sugarcane in Pakistan was overexpressed in a bacterial expression system ( E. coli ) and the recombinant fusion CP was purified and mobilized in mice for the development of polyclonal antibodies. In addition, the optimization, validation, and standardization of ELISA immunodiagnostics were reported herein. Section title: 2.1. Phylogenetic and physicochemical analysis Educational score: 4.188241481781006 Domain: biomedical Document type: Study Language: en The CP gene sequence of the SCMV isolate was obtained from GenBank 1 and subjected to alignments by MUSCLE software, built into MEGA X v10.1.8 and phylogenetic analysis was performed by the maximum-likelihood (ML) method, using the codon-based alignments with 1000 bootstrap replicates. The physicochemical characteristics were meticulously computed using the widely recognized ExPASy ProtParam online tool 2 . A 3D structural model was generated using I-TASSAR 3 and SWISS-MODEL 4 , respectively. PyMOL-2.5.7 5 was used to illustrate the structure produced by the I-TASSER server’s PDB data . The presence of signal peptides and cellular localization was predicted using online web servers 6 like SOSUI series system 7 and PSORTb version 3.0.3 8 . Section title: 2.2. Immunogenic analysis Educational score: 4.093031406402588 Domain: biomedical Document type: Study Language: en Immunogenic analysis was performed using the immune epitope database (IEDB) 9 and the Optimum Antigen™ design tool (GenScript, Piscataway, NJ, USA) 10 and their potential B-cell epitopes were predicted with a default threshold of 0.1512 by BepiPred-3.0 Linear Epitope Prediction tool 11 . Section title: 2.3. Transformation and subcloning expression cassette Educational score: 4.131712913513184 Domain: biomedical Document type: Study Language: en The final expression cassette (SCMVCpaj405) was commercially synthesized from Macrogen Inc. Korea in pUC57 and subsequently cloned in pET28 (a+) vector using restriction endonuclease sites Nde I and Hind III (Cat #R008S) to generate the 6×His-tagged SCMVCpaj405- pET28 (a+) plasmid, which was then used to transform DH5 α ( E. coli ) competent cells. Positive transformants were screened using restriction digestion and DNA sequencing before being used to transform E. coli BL21 CodonPlus competent cells for gene expression. Section title: 2.4. Expression optimization and purification of fusion protein Educational score: 4.162685394287109 Domain: biomedical Document type: Study Language: en The expression of the 6×His-SCMVCpaj405 fusion protein was induced by adding the synthetic inducer, IPTG, at concentrations of 0.1, 0.5, and 1 mM for 3 and 6 h at 37 °C. The bacterial cultures were centrifuged for 15 min at 4000 rpm and 4 °C. The resultant pellets were suspended in 50 mM Tris-HCl pH 8.0 buffer and sonicated for 30 min on ice with a pulse of 20-s on, 40-s off cycle to disturb them. The total protein extracts were separated into fractions (soluble and insoluble) by centrifugation at 12,000 rpm for 20 min at 4 °C prior to the large-scale production of recombinant protein, which was induced for 6 h at a concentration of 0.5 mM IPTG. The purification was carried out under native conditions (as a soluble protein) using Ni-NTA (resin Bio-Rad Laboratories, Inc. California, USA) affinity chromatography. To remove the imidazole, the purified recombinant protein fractions were mixed and dialyzed against a phosphate buffer saline (pH 8.0) overnight at 4 °C. The protein’s purity was verified on 12% SDS-PAGE. The Bradford assay was used to determine the protein concentration by using bovine serum albumin (BSA; Merck, Germany) as a standard protein. This recombinant protein was then utilized as an antigen to develop mouse-based polyclonal antibodies in the following phase. Section title: 2.5. Production of mouse polyclonal antibodies and serum collection Educational score: 4.095710277557373 Domain: biomedical Document type: Study Language: en The animals were housed in a controlled environment (temperature, light, and 12-h light/dark cycle) at the School of Biological Sciences (SBS), University of the Punjab, Lahore, Pakistan, where they always had access to food and water. Mouse polyclonal antisera to fusion protein were raised in albino female mice (Swiss Webster white strain, 4–6 weeks old) upon the approval by the Ethics Committee of SBS according to the protocol outlined by Salem et al. . The mice were given an initial dose of 100 g of recombinant CP with the same volume of Freund’s complete adjuvant (Santa Cruz Biotechnology, Dallas, TX, USA), followed by four weekly intraperitoneal booster injections of 200 g without removing the 6×His-tag with incomplete adjuvants (Santa Cruz Biotechnology). The mice were given deep anesthesia with ketamine hydrochloride (50 mg/kg of animal body weight) and xylazine (5 mg/kg of animal body weight) through intraperitoneal administration prior to blood collection through the cardiac puncture . The blood was centrifuged at 4000 rpm after being incubated for 1 h at 37 °C and antisera were stored at −20 °C for further analysis. Section title: 2.6.1. Optimization of raised antisera and antigen Educational score: 4.17067813873291 Domain: biomedical Document type: Study Language: en According to the standard protocol, three independent experiments were performed for the preparation and characterization of raised antibodies in mice. Raised antisera and antigen coating conc was optimized by serial dilution method as outlined by Darsono et al. with modification of a dilution factor extended from 50X to 10,000X to accommodate the specific requirements of our study. The antigen (200 μL; 100 ng/well) was prepared in borate buffer (50 mM KCl borate, pH 8.0) and used to coat the wells of a microtiter plate. The next day, the coating solution was removed and washed three times with 1X PBST buffer with continuous shaking for 5 min. The vacant binding sites were saturated with a blocking reagent to reduce nonspecific binding to the surface, and 200 μL of blocking buffer (5% (W/V) skim milk in TBS-T) was added to each well followed by incubation at 37 °C for 2 h. After incubation, the wells were cleaned as before and dried. To detect the immunoreactivity the anti-mouse HRP conjugated IgG antibody produced in rabbits was diluted (50,000X) in blocking buffer and added to each well (200 μL/well). After incubation at 37 °C for 1 h, the wells were washed three times with 1X PBST buffer with continuous shaking for 5 min (200 μL/well) and dried. The plate was incubated at RT for 15 min for blue color development. The reaction was stopped by the addition of 2 M H 2 SO 4 (100 μL/well). To analyze the antibody titer, the differential OD450/630 absorbance was measured at 405 nm using a microplate reader (HUMAREADER plus, human GMBH). All the mice’s serum samples were replicated twice for their immunoreactivity, the values were recorded, and averages were calculated. The standard curve was plotted for different concentrations of antigen, i.e. 10 pg, 50 pg, 100 pg, 200 pg, 500 pg, 1 ng, 5 ng, 50 ng, 100 ng, 200 ng, 500 ng, 1 μg, and 2 μg were used in the optimization process with immunized mice and negative controls. The rest of the ELISA procedure followed the same methodology as described before. Section title: 2.7. Indirect ELISA Educational score: 4.0486602783203125 Domain: biomedical Document type: Study Language: en In the indirect ELISA, the sensitivity of the raised antisera was evaluated by serial dilution . The effectiveness and specificity of the raised antiserum in detecting the SCMV in various test samples were evaluated using targeted purified fusion protein, bacterial cell extracts (both recombinant and nonrecombinant plasmids), and total proteins extracted from healthy and SCMV-infected sugarcane plants . Section title: 2.8. RT-PCR Educational score: 4.06933069229126 Domain: biomedical Document type: Study Language: en Using TRI REAGENT ® (Cat. #TR118), total RNA was meticulously extracted from 0.1 g of plant leaf tissues sourced from the field, encompassing both healthy samples and those displaying characteristic mosaic symptoms suggestive of mosaic disease for subsequent RT-PCR analysis. For the confirmation of the SCMV-infected sugarcane sample, the CP gene-specific primers (SNd-Cp-F CATATGGCTG-GAACAGTCGATGC and SHd-Cp-R AAGCTTCTAGTGGTGCTGCTGCAC) were designed using Primer3Plus and used in QIAGEN OneStep RT-PCR analysis, according to the manufacturers’ instructions. Section title: 2.9. Statistical Analysis Educational score: 3.798809289932251 Domain: biomedical Document type: Study Language: en Before the statistical analysis, the data were checked for whether they were normally distributed or not. Then with the help of one-way analysis of variance (ANOVA), the Tukey post-hoc test, and GraphPad Prism software 8.0 (USA), statistical analysis and inferences were carried out. According to the Tukey post-hoc test using the least significant difference test, comparisons between treatments were deemed statistically significant at p < 0.05. All experiments were replicated twice. Data from three independent experiments are presented as mean and standard error. Section title: 3.1. Physicochemical and immunogenic analysis Educational score: 4.3544793128967285 Domain: biomedical Document type: Study Language: en The physicochemical characteristics of native and fused CP-SCMV protein sequences were compared using ExPASy ProtParam ( Table 1 ). The nucleotide sequence translation to amino acids showed that both the native and 6×His tag CP genes code for 314 and 321 aa proteins, respectively. The computational prediction of isoelectric point (pI) and molecular weight of the proteins showed that they have pI values approximately the same, with native CP having a pI of 6.80 and the 6×His tag CP having a pI of 7.00 with theoretical protein mass of 33.8 kDa (native CP) and 34.7 kDa (6×His tag CP). The predicted protein size for rCP is around 34.7 kDa since the pET 28a (+) vector adds a few amino acid linkers and a 6×His tag to the protein’s N-terminus, adding roughly ~1 kDa . Two different tools (PSORTb and SOSUI) were used to determine the subcellular localization of native and fused proteins in E. coli . The PSORTb result revealed an unknown subcellular localization for both proteins; however, the SOSUI analysis showed a periplasmic subcellular localization for both proteins. The soluble proteins were predicted by the tools SOSUI signal and Signal P 5.0 without a signal peptide . Furthermore, the antigenic determinants of CP-SCMV were located in eight distinct stretches: ETGSVTGGQRDKDV, MSKKMRLPKAKGKD, PQQQDISNTRATRE, KKEYEIDDTQMTVV, DGDEQRVFPLKPVI, YRNSTERYMPRYGL, EMNSRTPARA-KEAH, and NVGETQENTERHTA, which were present at the upper surface of the 3D structure ( Supplementary Table S3 ). Section title: 3.2. Production and purification of 6×His-SCMVCpaj405 fusion protein Educational score: 4.1704864501953125 Domain: biomedical Document type: Study Language: en A 40 kDa overexpressed protein band was observed in BL21 DE3 culture in setups transformed with the 6×His-SCMVCpaj405-pET-28a (+) vector and induced by IPTG (0.1, 0.5, 1.0 mM, 3 h and 6 h) at 37 °C, as shown in Figure 2a . When examining the intensity of the 40 kDa band size for 3 h and 6 h of incubation, there was an increase in band size. Protein was purified under native conditions. SDS-PAGE analysis of elution fractions (450 and 500 mM of imidazole) under native conditions using the Ni-NTA column confirmed that the eluted protein was SCMVCpaj405 tagged with 6×His . Protein elutions were mixed, and dialysis was used to eliminate extra imidazole. Using BSA as the standard, the resultant solution was subjected to the Bradford test to determine the eluted protein concentration. According to the findings, 2 mg of recombinant SCMVCpaj405 protein was produced per 200 mL of BL21 (DE3) culture . Section title: 3.3. Development and evaluation of polyclonal antibodies Educational score: 4.141902446746826 Domain: biomedical Document type: Study Language: en Initially, all three immunized and nonimmunized (control) animals’ antisera were tested for antibody production using indirect ELISA. The ELISA results for the immunized mice were positive and virtually comparable, in contrast with the nonimmunized mice, which showed negative results . To establish the optimal coating concentration for the raised primary pAb antibody, serial dilution was used with a fixed amount of pure SCMVCpaj405 fusion protein antigen (100 ng/well) . Antisera targeting the SCMVCpaj405 fusion protein effectively detected the antigen across a wide dilution range, from 50X to 10,000X. The mean absorbance at 405 nm of the SCMVCpaj405 fusion protein antigen exhibited a gradual decrease, ranging from 3.094 (50X) to 1.719 (10,000X). Notably, the absorbance values of the buffer and healthy control (0.183) were consistently lower than that of the antigen . The purified SCMVCpaj405 fusion protein antigen remained readily identifiable up to a 10,000X dilution, where the mean absorbance value of 1.719 surpassed the established threshold value (TV) of 0.312. A sample was deemed significant if its mean absorbance value exceeded the TV. Section title: 3.3. Development and evaluation of polyclonal antibodies Educational score: 4.104770183563232 Domain: biomedical Document type: Study Language: en The sensitivity of the antisera was further evaluated by using indirect ELISA analysis at dilutions ranging from 50X to 10,000X to crudely extracted proteins from both healthy and infected sugarcane leaves. The crude extracts’ dilution steadily dropped, from 2.0 (50X) to 0.028 (10,000X) dilution at A405 nm. The raised antibody generated the strongest signal to identify virus particles in plant sap that had been diluted 1:50 and 1:100 , with letters (a, b, c, d, etc.) showing statistically significant differences between variables. Section title: 3.3. Development and evaluation of polyclonal antibodies Educational score: 4.0705108642578125 Domain: biomedical Document type: Study Language: en Indirect ELISA was also used to evaluate the effectiveness and specificity of the raised antiserum to various test samples. The raised antibodies reacted positively against purified fusion protein, total cell lysate from bacterial cells transformed with recombinant plasmid , and total extracted proteins from SCMV-infected sugarcane plant in the indirect ELISA. Nevertheless, no signal was detected against the nonrecombinant plasmid extract or in the healthy plant total extract ( Table 2 ). Section title: 3.4. The standard curve Educational score: 4.205041408538818 Domain: biomedical Document type: Study Language: en To quantitatively measure SCMV in plant tissues using indirect ELISA, a standard curve was established by serially diluting SCMVCpaj405 fusion CP (10 pg to 2 μg). The resulting linear regression between SCMVCpaj405 fusion CP concentration and OD450 absorbance was described by the equation y = 0.0922x + 0.0471 with a correlation coefficient (R 2 ) of 0.957. This analysis indicated a minimum detection limit of approximately 100 pg/mL for SCMVCpaj405 fusion CP. Furthermore, the linear regression model demonstrated a working range of 100 pg/mL to 500 ng/mL . Finally, PCR-based confirmation was performed with SCMVCpaj405-specific primers SNd-Cp-F and SHd-Cp-R using the same healthy and SCMV-infected sugarcane field-grown plant used in the ELISA. Total extracted RNA was used as a template to create 1st strand cDNA by reverse transcription, and one-step RT-PCR successfully amplified the full length SCMV CP gene from infected sugarcane field-grown plant but not in a healthy one, which confirmed the presence of SCMV . Section title: Discussion Educational score: 2.860747814178467 Domain: biomedical Document type: Other Language: en SCMV significantly impacts sugarcane yield and quality, posing a challenge for the production of healthy, virus-free planting material, given that sugarcane is predominantly propagated through vegetative means. A high-throughput diagnostic method is crucial for ensuring the quality of planting material. Essential to such diagnostics are high-quality antisera, which can be produced by generating polyclonal antibodies against recombinant viral proteins. Section title: Discussion Educational score: 4.055974006652832 Domain: biomedical Document type: Study Language: en In the present study, we successfully subcloned the CP gene of SCMV and expressed it in E. coli BL21 (DE3) cells. CP is frequently utilized as an antigen for polyclonal antibody production because it is highly conserved across different virus strains. This conservation allows broad-spectrum detection of SCMV, whether the virus is in an active replication phase or in an inactive state . Section title: Discussion Educational score: 4.155726432800293 Domain: biomedical Document type: Study Language: en The pET28a (+) bacterial expression vector, equipped with a T7 promoter for protein expression in E. coli and an N-terminal 6×His tag for purification and detection, was chosen due to the anticipated nonimmunogenicity of the 6×His tag . As expected, the 6×His tag facilitated efficient affinity purification of the recombinant protein without compromising the diagnostic potential of the polyclonal antiserum. Induction of transformed E. coli BL21 (DE3) cells with 0.5 mM IPTG successfully yielded recombinant SCMV CP, with protein production increasing proportionally to the postinduction incubation time . Section title: Discussion Educational score: 4.21278190612793 Domain: biomedical Document type: Study Language: en Purification of the recombinant SCMV CP under native conditions revealed its predominant localization in the soluble fraction of E. coli whole-cell protein extract. The purified protein exhibited a molecular size of approximately 40 kDa, which was larger than the predicted 34.7 kDa. This observation aligns with previous findings by Jensen et al. that SCMV-induced CP size can vary among isolates in plant tissues, ranging from 34.4 to 39.7 kDa . Furthermore, it is consistent with studies on recombinant CPs from other plant viruses such as tomato spotted wilt tospovirus , apple stem grooving virus , and Citrus psorosis virus . The recombinant fusion protein was observed to be predominantly in the soluble phase. Section title: Discussion Educational score: 4.097768783569336 Domain: biomedical Document type: Study Language: en Evaluation of the antibody titer involved assessing the raw antiserum’s ability to recognize the target antigen in SCMV-infected sugarcane samples. The results indicated that the mouse anti-SCMV CP antibodies could successfully react to SCMV-infected sugarcane samples up to a dilution of 1:10,000 of raw antiserum . While cross-reactivity between antisera and their corresponding antigens is a potential concern, it is expected due to the frequent amino acid sequence and structural similarities among plant viral antigens within the same virus family, as documented in prior research . Section title: Discussion Educational score: 4.0809526443481445 Domain: biomedical Document type: Study Language: en The primary objective of immunodiagnosis in asymptomatic sugarcane plants is to determine the presence or absence of viral infections, regardless of the specific SCMV strain. Precise viral identification, a distinct goal, is better achieved through more specialized diagnostic techniques like PCR, monoclonal antibodies, or nanobodies . The concordance of indirect ELISA and PCR findings to identify SCMV in sugarcane shows that the anti-SCMV CP is applicable for SCMV detection in field-collected samples. Section title: Discussion Educational score: 4.100584030151367 Domain: biomedical Document type: Study Language: en The present study highlights the advantages of recombinant DNA technology over traditional viral purification methods, offering efficient bulk antigen synthesis for immunization. While native viral proteins from isolated virus particles maintain their original conformation, recombinant proteins can also be produced with similar structural integrity. The 6×His tag, shown to be beneficial in previous research, can be retained while optimizing protein expression conditions like incubation temperature and IPTG concentration to enhance solubility in E. coli . Section title: Discussion Educational score: 4.1696295738220215 Domain: biomedical Document type: Study Language: en Our findings and prior studies indicate that overexpressed proteins in E. coli often localize to the soluble phase. In silico predictions using SOSUI-GramN aligned with this observation, suggesting a periplasmic subcellular location for SCMV CP. Elfageih et al. reported that alkaline phosphatase facilitates the correct folding of proteins with disulfide bonds in the periplasm. Consequently, recombinant viral proteins expressed in E. coli can be reliably purified under native conditions, preserving their overall native conformation. Section title: Discussion Educational score: 4.006162166595459 Domain: biomedical Document type: Study Language: en However, our work demonstrates that recombinant DNA technology is a productive and economical method of producing polyclonal antibodies against SCMV CP. In order to enable efficient disease control within sugarcane plantations, the generated antisera against SCMV CP may be effectively employed for the detection of SCMV in asymptomatic sugarcane plants. Furthermore, future research that makes use of the preliminary results from the present study can address the problem of specificity to further distinguish or discriminate between SCMV strains-infected sugarcane. Section title: Conclusions Educational score: 3.447688341140747 Domain: biomedical Document type: Study Language: en In the present study, the antibodies developed against the SCMV CP proved effective for detecting both the purified CP and the virus itself using ELISA. The availability of these antibodies enhances the ability to screen plant material in sanitation programs and supports research into the virus’s pathogenicity. | Study | biomedical | en | 0.999997 |
PMC11698197 | Section title: Introduction Educational score: 4.009519577026367 Domain: biomedical Document type: Review Language: en The uncontrolled multiplication of melanocytes, skin pigment-producing cells, is the cause of melanoma, a type of malignant skin cancer. Despite being generally known to develop on the skin, melanoma can also occur on mucosal surfaces inside the body or in other regions including the uveal tract, where neural crest cells migrate 1 . Skin cancer is the prominent cause of malignancy and invasive melanoma accounts for around 1% of all skin malignancies; however, it is responsible for the majority of mortalities 1 . An estimated 325,000 new cases of melanoma (174,000 males and 151,000 females) were identified worldwide in 2020, with 57,000 deaths . Section title: Introduction Educational score: 4.416252136230469 Domain: biomedical Document type: Review Language: en While early detection and surgical removal of tumors remain the cornerstone of therapy, metastatic melanoma remains difficult to treat with limited treatment options. Therapy strategies, such as chemotherapy, targeted therapy, radiation therapy, surgical operation, and immunotherapy vary depending on the stage of melanoma, the thickness and growth rate of the tumor, and the genetic type of the melanoma . The most effective treatments are immunotherapy and radiotherapy compared to chemotherapy with the Food and Drug Administration-approved drug for melanoma, i.e. dacarbazine, which is less frequently preferred . Despite its potent action, the therapeutic impact of dacarbazine in the treatment of melanoma cancers is diminished by its poor water solubility and brief half-life (41 min) in blood circulation . Moreover, the limitations of a single agent therapy were demonstrated by a depressing response rate of between 10% and 25% and less than 5% total cancer recovery . Therefore, there is a high demand for novel chemotherapeutic approaches in the treatment of melanoma. Recent studies have provided evidence of the promising biological activities of all-trans retinoic acid (ATRA), and sphingomyelin (SM) on melanoma . Section title: Introduction Educational score: 4.6153082847595215 Domain: biomedical Document type: Review Language: en ATRA, a natural metabolite of vitamin A, has shown therapeutic potential against melanoma by inducing differentiation, apoptosis, growth arrest, and immune modulation in cancer cells . Specifically, ATRA mediates the transcription of many cell differentiation genes on retinoic acid receptors (RARs) in a variety of cancers such as acute promyelocytic leukemia and melanoma, resulting in the activation of ATRA-dependent RARs and retinoid X receptors in the nucleus, thereby providing differentiation in the cancer cells . ATRA treatment also leads to a decrease in DNA synthesis, alterations in cellular morphology, and extended doubling time, and the induction of cell cycle arrest, specifically in the G1 phase through the suppression of oncogenic signaling pathways . The current preclinical and clinical evidence provides support for its utilization in the context of melanoma treatment, which was approved under the name Vesanoid for the treatment of acute promyelocytic leukemia that does not respond to any chemotherapy . While ATRA has demonstrated significant efficacy in treating several forms of cancer such as melanoma, it is important to note that the use of ATRA as a standalone treatment can result in the development of resistance and subsequent relapse . Therefore, new strategies can offer valuable insights into the development of the advancement of strategies focused on enhancing the administration of ATRA as a standalone therapeutic agent or in combination with other treatments, as well as overcoming drug resistance. Section title: Introduction Educational score: 4.315202713012695 Domain: biomedical Document type: Study Language: en In addition, ATRA has an impact on the immune system through the differentiation of myeloid-derived suppressor cells (MDSCs) into macrophage and dendritic cells at the level of preclinical and clinical phase studies. In two clinical studies, ATRA was targeted in combination with immunotherapeutics to MDSCs in patients with cancer, including metastatic renal and lung cancers . Two clinical studies demonstrated that decreasing the quantity of MDSCs leads to improved patient survival. A phase 2 clinical study investigated the efficacy of combining ATRA with ipilimumab in individuals diagnosed with stage 4 melanoma . Furthermore, ongoing clinical trials are investigating the efficacy of combining the programmed death ligand 1 (PD-L1) inhibitor pembrolizumab (Keytruda) with ATRA (Vesanoid) as a treatment for metastatic melanoma . The clinical research assess the efficacy of the combination by decreasing the quantity and inhibitory function of immunosuppressive MDSCs in the peripheral blood of melanoma patients, hence halting the advancement of the illness. Considering the chemotherapeutic approach together with immunotherapy, the combinational treatment of ATRA and sphingolipids have been identified as potential anticancer agents that exhibit synergistic effects by inducing apoptosis and inhibiting cancer cell proliferation . Section title: Introduction Educational score: 4.7425737380981445 Domain: biomedical Document type: Study Language: en SM, a specific class of sphingolipids found in cell membranes, has lately gained attention in cancer research owing to its potential anticancer effects as tumor-suppressing biologically active lipids . The modulation of numerous signaling pathways involved in melanoma progression, such as the mitogen-activated protein kinase and phosphoinositide 3-kinase/protein kinase B (AKT) pathways, has been engaged in the regulation of cell proliferation, differentiation, and apoptotic cell death in melanoma cells . Moreover, SM has been reported to inhibit the growth and spread of melanoma cells by inducing cell death and limiting the formation of new blood vessels in the tumor . The anticancer properties of SM have been linked with the accumulation of ceramide and induction of apoptosis . Over the SM cycle, the destruction of SMs and the production of phosphocholine and ceramide result in the activation of neutral sphingomyelinases (nSMase). Ceramides reduce protein phosphorylation, and expression of protooncogenes such as c-Myc, and modulate apoptosis . León et al. showed that C2-ceramide has a cytotoxic effect on the SK-MEL-1 melanoma cell line, which was consistent with the other studies linked to the antitumor effects of ceramide-based nano-formulations on melanoma cells . Additionally, it was stated that the combinational treatment of nano-liposomal ceramide and sorafenib synergistically inhibited melanoma and breast cancer cell proliferation to reduce the development of the tumor . On the other hand, the effect of ATRA on the SM cycle was researched through sphingomyelinase (SMase) expression on MCF-7 (ATRA-sensitive) and MDA-MB-231 (ATRA-resistant) breast cancer cells . Accordingly, an increase in SMase activity was observed in the MCF-7 cell line, but not in the MDA-MB-231 cells, which are dependent on ATRA-sensitivity. In another study by Clarke et al. , they reported that growth arrest in ATRA-induced MCF-7 breast cancer cells was mediated by the SMase expression. Estrogen receptor-positive MCF-7 cells were employed as a model system in order to investigate the involvement of nSMase 2 (nSMase2) and sphingolipids in the growth arrest produced by ATRA . The findings indicated that ATRA leads to an elevation in ceramide levels and induces growth arrest in MCF-7 cells by upregulating the expression of nSMase2. Furthermore, nSMase2 was identified as the primary enzyme in the sphingolipid network of MCF-7 cells that was regulated by ATRA. These previous findings put the combinational approach forward as a prominent therapy for tumor-resistant agents such as ATRA. Section title: Introduction Educational score: 4.1184210777282715 Domain: biomedical Document type: Study Language: en With the implemented approach, the present study introduces the combinational therapy of ATRA and SM to synergistically improve activity and apoptosis, and hence attain a combinational anticancer effect on the in vitro B16F10 melanoma model, whereas determination of the safety of the treatment on immune cells was performed via cell viability studies on healthy macrophages. Also investigated was the overall effect of the combinational therapy on various cellular parameters, including cell viability, apoptotic cell death, and cell cycle, as well as gene expression levels to gain insights into the molecular interactions between the two active compounds and the B16F10 melanoma cells. Section title: 2.1. Materials Educational score: 1.9505828619003296 Domain: biomedical Document type: Study Language: en The materials used in the study comprised 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay (CellTiter96 AqueousOne Solution) (Promega UK Ltd., Chilworth, Southampton, UK); Annexin V-fluorescein isothiocyanate (FITC) Apoptosis Detection Kit (BD Biosciences Pharmingen, San Diego, CA, USA); propidium iodide and ribonuclease A (RNase A) (Sigma-Aldrich Chemie GmbH, Steinheim, Germany); octylphenoxypolyethoxyethanol (nonidet P-40) (AppliChem GmbH, Darmstadt, Germany); TRIzol reagent (Thermo Fisher Scientific Inc., Waltham, MA, USA); cDNA Synthesis Kit (Qiagen Inc., Germantown, MD, USA); and iTaq Universal SYBR Green Supermix (Bio-Rad, Hercules, CA, USA). Section title: 2.2. Cell culture Educational score: 4.101927757263184 Domain: biomedical Document type: Study Language: en The murine macrophage RAW264.7 (TIB-71) and murine melanoma B16F10 cells were obtained from the American Type Culture Collection (Rockville, MD, USA). The cells were cultured in Dulbecco’s modified eagle’s high medium supplemented with 10% inactivated fetal bovine serum (Invitrogen Life Technologies, Waltham, MA, USA). The medium also contained 2 mM of L-glutamine, as well as 100 U/mL of penicillin and 100 μg/mL of streptomycin (Gibco, Thermo Fisher Scientific Inc.). The cells were maintained at 37 °C in a controlled atmosphere containing 5% CO 2 . Section title: 2.3. Cell viability analysis Educational score: 4.126330375671387 Domain: biomedical Document type: Study Language: en The RAW264.7 macrophages and B16F10 melanoma cells were subjected to incubation in the presence of ATRA (in ethanol), SM, and various combinations of both for 24, 48, and 72 h. The determination of cell viability was conducted using MTS assay. Accordingly, the RAW264.7 and B16F10 cells were cultured in 96-well plates at a seeding density of 10,000 and 5,000 cells per well, respectively. Following incubation for 24, 48, and 72 h, the cells were subjected to treatment with varying doses of ATRA and SM at concentrations from 5 to 200 μM, both individually and in combination. After incubation, the cells were incubated in a solution of 10% MTS with glucose and 1X phosphate buffered saline (PBS) for 1 h. The absorbance at 490 nm was read using a microplate spectrophotometer (ELx800; BioTek Instruments Inc., Winooski, VT, USA). Cell viability was calculated as percentages by setting the absorbance of the untreated control group to 100%. The data were then analyzed using GraphPad Prism 8.0.1 (San Diego, CA, USA) to establish the half-maximal inhibitory concentration (IC 50 ), and half-maximal cytotoxic concentration (CC 50 ). The selectivity index (SI) of free ATRA and SM was calculated using the following equation: SI = CC 50 in the RAW264.7 macrophage cell line / IC 50 in the B16F10 melanoma cell line. Section title: 2.4. Cell cycle analysis by flow cytometry Educational score: 4.126434326171875 Domain: biomedical Document type: Study Language: en The distribution of the cell cycle in the B16F10 cells was assessed by flow cytometry at 24 h. The B16F10 cells were seeded in 12-well plates with a density of 60,000 cells per well and incubated for 24 h. Following incubation, the cells were treated with ATRA (123 μM), SM (136 μM), and a combination of both (123 μM ATRA+136 μM SM) for 24 h. After 24 h of incubation and fixation with 70% ethanol, the cells were mixed with 0.01% nonidet P-40, and 100 μg/mL RNase A for 30 min. The analysis was performed with a flow cytometer for the gating of 10,000 cells after 5 min of incubation with 5 μg/mL of propidium iodide (PI). The percentages of cell populations were determined in the gap 0 (G0)/G1, synthesis (S), and G2/mitosis (M) phases. Section title: 2.5. Apoptosis assay Educational score: 4.1229753494262695 Domain: biomedical Document type: Study Language: en Apoptotic cell death of the B16F10 cells was analyzed via the Annexin V FITC/PI assay using a flow cytometer. Briefly, the B16F10 cells were seeded on 12-well plates with a density of 60,000 cells per well and incubated for 48 h. After incubation, the cells were treated with ATRA (123 μM), SM (136 μM), and a combination of both (123 μM ATRA+136 μM SM). After 48 h of incubation, they were subsequently exposed to Annexin V-FTIC for 15 min, followed by PI for 1 min, in line with the manufacturer’s instructions. The samples were examined using a FACSCalibur instrument (BD Biosciences, San Jose, CA, USA). A minimum of 10,000 cell counts were obtained for each data file. The gating procedure was appropriately adjusted to remove cellular debris, doublets, and clumps. Section title: 2.6. Quantitative PCR (qPCR) analysis Educational score: 4.070454120635986 Domain: biomedical Document type: Study Language: en Primers for caspase 3 (CASP3) F: 5′ GGGAGCAAGTCAGTGGACTC 3′ and R: 5′ CCGTACCAGAGCGAGATGAC 3′; Bax F: 5′ TTGGAGCAGCCGCCCCAGG 3′ and R: 5′ CGGCCCCAGTTGAAGTTGCC 3′; programmed cell death-ligand 1 (PD-L1) F: 5′ TGGTCATTGTGCTGCTGCTA 3′ and R: 5′ TTACAGTTCGGCTGTCCACC 3′; cyclin-dependent kinase inhibitor 2A (CDKN2A) F: 5′ GAACTCGAGGAGAGCCATCTG 3′ and R: 5′ CCATCATCATCACCTGAATCGG 3′ were facilitated through the utilization of the Primer-BLAST online program, provided by the National Center for Biotechnology Information (Bethesda, MD, USA) and synthesized by Sentebiolab Biotech (Ankara, Turkey). The isolation of total RNAs from the samples was performed using TRIzol reagent. The cDNAs were synthesized using a cDNA-Synthesis Kit. iTaq Universal SYBR Green Supermix was employed in the qPCR analysis to measure the mRNA expression levels of the target genes. The gene ß-actin, a housekeeping gene, was employed to normalize the collected data. The iCycler reverse transcription (RT)-PCR machine (Bio-Rad) was utilized for all the RT-PCR assays. Section title: 2.7. Statistical analysis Educational score: 3.334528923034668 Domain: biomedical Document type: Study Language: en GraphPad Prism Software (version 8.0.1) was employed for the statistical analyses. Error bars were utilized to visually represent the standard error of the mean. The datasets underwent initial ordinary one-way analysis of variance (ANOVA), followed by two-way ANOVA, and were subsequently scrutinized using Tukey’s multiple comparison test. Statistical significance was established at the following thresholds: * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, and **** p ≤ 0.0001. Section title: 3.1. RAW264.7 macrophage and B16F10 melanoma cell viability after treatment with ATRA and SM Educational score: 4.093567371368408 Domain: biomedical Document type: Study Language: en The RAW264.7 macrophages and B16F10 melanoma cells were treated with ATRA, SM, and a combination of both at concentrations ranging between 5 and 200 μM for 24, 48, and 72h. In the combination treatments, the concentrations of ATRA (free) and SM (free) were based on their respective IC 50 values, as follows: IC 50 /2 ATRA + IC 50 /2 SM, IC 50 /2 ATRA + IC 50 SM, IC 50 ATRA + IC 50 /2 SM, IC 50 /3 ATRA+ IC 50 /3 SM, IC 50 /3 ATRA + IC 50 SM, IC 50 ATRA + IC 50 /3 SM, 200 μM ATRA+ IC 50 /2 SM, IC 50 /2 ATRA+200 μM SM. In the positive control group, the cells were treated with 0.1% (v/v) ethanol to track the impact of the presence of the solvent (i.e. ethanol). The cell viability data of the MTS assay are presented in Figure 1 . Section title: 3.1. RAW264.7 macrophage and B16F10 melanoma cell viability after treatment with ATRA and SM Educational score: 4.136136054992676 Domain: biomedical Document type: Study Language: en The cell viability data of the RAW264.7 cells as a healthy cell line indicated that treatment with SM led to a gradual decrease in the viability of the RAW264.7 cells as the SM concentration increased to 150 μM (from 20% to 17%) and 200 μM (from 6% to 4%) . On the contrary, there was no significant change in cell viability with 20 μM of SM (from 93% to 91%) at any of the time intervals. The viability of the RAW264.7 cells decreased insignificantly from 99% to 85% with 40 μM of SM, from 100% to 87% with 50 μM of SM, and from 91% to 80% with 75 μM of SM, within 24 and 72 h respectively. However, a significant decrease to 31% and 17% occurred when the RAW264.7 cells were treated with 150 μM of SM for 48 and 72 h, respectively . On the other hand, cell viability decreased gradually to 25% and 22% with 150 and 200 μM of ATRA at 72 h, respectively . No significant change occurred in the viability of the RAW264.7 macrophages when treated with 5, 10, and 40 μM of free ATRA at 24, 48, and 72 h. Section title: 3.1. RAW264.7 macrophage and B16F10 melanoma cell viability after treatment with ATRA and SM Educational score: 4.134820938110352 Domain: biomedical Document type: Study Language: en Treatment with SM up to 100 μM caused no significant alteration in the viability of B16F10 melanoma cells, while treatment with 150 and 200 μM led to a significant decrease to 8% and 5% in the B16F10 cell viability , respectively, at 24 h . Similarly, up to a 15% decrease in cell viability was observed at 48 h with 200 μM of SM, whereas at 72 h, cell viability of the B16F10 cells was 6% and 11% with 150 and 200 μM of SM, respectively . On the other hand, with 150 and 200 μM of ATRA, the cell viability decreased significantly below 15% at 72 h. With the 200 μM ATRA treatment, B16F10 cell viability decreased further down to 16%, 12%, and 8% at 24, 48, and 72 h, respectively (p ≤ 0.01) . On the other hand, treatment with 5–50 μM of ATRA led to an increase in cell viability above 100% with low concentrations (i.e. 5–20 μM) at 24 and 48 h . Section title: 3.1. RAW264.7 macrophage and B16F10 melanoma cell viability after treatment with ATRA and SM Educational score: 4.128808975219727 Domain: biomedical Document type: Study Language: en The growth inhibition in the B16F10 and RAW264.7 cells allowed the calculation of both the IC 50 and CC 50 values for the free ATRA and SM . While the IC 50 values for the free ATRA and free SM were 123 ± 16.23 and 136 ± 15.03 μM at 72 h, respectively, for the B16F10 cells, the CC 50 values for the free ATRA and SM were 99.54 ± 1.55 and 104.7 ± 2.05 μM, respectively, for the RAW264.7 macrophages. The selectivity index values for the ATRA and SM on the melanoma cancer model were 0.81 and 0.77, respectively. Considering the IC 50 and CC 50 values, among the effective concentrations on B16F10 melanoma cells, the optimum concentration of ATRA and SM for further combinational treatment studies (i.e. cell viability, apoptosis, cell cycle, and qPCR) was 123 and 136 μM, respectively, which was relatively safe in the healthy control RAW264.7 macrophage cells at 24, 48, and 72 h of incubation. Section title: 3.1. RAW264.7 macrophage and B16F10 melanoma cell viability after treatment with ATRA and SM Educational score: 4.107784748077393 Domain: biomedical Document type: Study Language: en As shown in the cell viability analysis of the RAW264.7 cells after the combinational therapy , there was no significant change in cell viability at 24 h with any of the concentrations, whereas 200 μM ATRA+68 μM SM and 61.5 μM ATRA+200 μM SM led to significant reductions in the macrophage cell viability at 48 and 72 h. Accordingly, the 200 μM ATRA+68 μM SM combination significantly decreased cell viability from 74% to 57% at 48 and 72 h. Likewise, the 61.5 μM ATRA+200 μM SM combination caused a significant decrease in cell viability to 25% at 72 h. On the contrary, the 123 μM ATRA+136 μM SM combination did not cause any significant change in the macrophage cell viability at 24, 48, and 72 h. Section title: 3.1. RAW264.7 macrophage and B16F10 melanoma cell viability after treatment with ATRA and SM Educational score: 4.197015762329102 Domain: biomedical Document type: Study Language: en Figure 1F shows the potential anticancer effect of the SM and ATRA combinational therapy, which was attributed to increasing the biological effect of the compounds on the B16F10 cells with the improved safety properties in the RAW264.7 macrophages. Combinations of 61.5 μM ATRA+68 μM SM, 123 μM ATRA+68 μM SM, 41 μM ATRA+136 μM SM, and 123 μM ATRA+45 μM SM did not lead to any significant alterations in the B16F10 cell viability at 24 and 48 h. While combinational treatments with concentrations up to 123 μM ATRA and 136 μM SM did not cause a significant decrease in the cell viability at 24 and 48 h, the values indicated a gradual decrease in B16F10 cell viability compared to the individual molecular treatments in a time-dependent manner. Furthermore, 72 h of incubation led to a significant decrease to 45.74% compared to the untreated group (p ≤ 0.01). When the B16F10 cells were treated with the 200 μM ATRA+68 μM SM combination, there was a significant decrease in cell viability (i.e. 17.81% and 25.79%) at 48, and 72 h, respectively . Similarly, the treatment of B16F10 melanoma cells with 61.5 μM ATRA+200 μM SM significantly decreased cell viability to 6.99% and 5.81% at 48 and 72 h, respectively . Accordingly, these results revealed that the coadministration of 123 μM of ATRA and 136 μM of SM enhanced the anticancer efficacy in the B16F10 melanoma cells by mitigating their cytotoxic effects on the RAW264.7 macrophages. Section title: 3.2. Effects of ATRA and SM on B1610 cell morphology Educational score: 4.129115104675293 Domain: biomedical Document type: Study Language: en Phase-contrast microscopy was employed to observe alterations in the morphological characteristics of the B16F10 cells treated with a combination of ATRA and SM . The untreated cells exhibited a flattened adherence to the surface , whereas 150 μM of SM , 150 μM of ATRA , as well as the 123 μM ATRA+136 μM SM combination , resulted in a significant alteration in the surface morphology and cell adhesion dramatically. The morphological characteristics of the flat surface underwent a transformation, resulting in a rounded spherical form, and they were separated from each other. Section title: 3.3. Cell cycle analysis Educational score: 4.0849151611328125 Domain: biomedical Document type: Study Language: en The cell cycle progression in the B16F10 cells after the SM and ATRA treatments was determined using flow cytometry analysis . The cell population percentage in the G0/G1 and G2/M phases varied depending on the treatment, demonstrating that cell cycle arrest was induced in the G0/G1 and G2/M phases at 24 h of incubation . Section title: 3.3. Cell cycle analysis Educational score: 4.157810688018799 Domain: biomedical Document type: Study Language: en At the end of 24 h, the mean ± standard deviation of the G0/G1 phase for the control group was 64.39 ± 2.32%, whereas it was 80.70 ± 6.08% for 123 μM of ATRA, 92.76 ± 4.45% for 136 μM of SM, and 64.53 ± 7.71 for the 123 μM ATRA+136 μM SM combination . Accordingly, as shown in Figure 3B , 123 μM of ATRA significantly increased the cell population (p ≤ 0.01) in the G0/G1 phase to 80.70 ± 6.08% in the B16F10 cells at 24 h. Similarly, the cell population in the G0/G1 phase increased significantly to 92.76 ± 4.45% with 136 μM of SM , whereas the 123 μM ATRA+136 μM SM combination significantly increased the cell population to 34.06 ± 7.30% (p ≤ 0.01) in the G2/M phase at 24 h. Overall, these results indicated cell cycle arrest in the G2/M phases after the combinational treatment of ATRA and SM at 24 h. Section title: 3.4. Effects of ATRA and SM on apoptotic cell death Educational score: 4.160778045654297 Domain: biomedical Document type: Study Language: en The apoptotic cell death in B16F10 cells following treatment with 123 μM of ATRA, 136 μM of SM, and the 123 μM ATRA+136 μM SM combination was assessed using Annexin V flow cytometry analysis, as illustrated in Figure 4 , after 48 h. Accordingly, the apoptotic population fraction of the cells was 37.98% with 123 μM of ATRA, 96.03% with 136 μM of SM, and 53.91% with the 123 μM ATRA+136 μM SM combination at 48 h . The early apoptotic population in B16F10 cells was 7.39% for the untreated control (NC), 21.81% for 123 μM ATRA, 34.19% for 136 μM SM, and 27.78% for the combined treatment. Meanwhile, the late apoptotic population rose from 5.32% in untreated cells to 16.17%, 61.84%, and 26.13% after exposure to 123 μM ATRA, 136 μM SM, and the combined treatment, respectively . Furthermore, apoptotic cell death increased to 37.98% and 96.03% with 123 μM of ATRA and 136 μM of SM alone when compared to the untreated group (i.e. 12.71%), and the 123 μM ATRA+136 μM SM combination led to a significant increase to 53.91% at 48 h (p ≤ 0.001) . On the contrary, the percentage of necrotic cells was negligible for all of the cell populations after incubation. Section title: 3.5. Effects of ATRA and SM on the gene expressions Educational score: 4.135406017303467 Domain: biomedical Document type: Study Language: en After treatment of the B16F10 cells with 123 μM of ATRA, 136 μM of SM, and the 123 μM ATRA+136 μM SM combination, the relative CASP3, Bax, PD-L1, and CDKN2A expressions of the cells were analyzed with qPCR at 24 h . The results showed that 136 μM of SM and the 123 μM ATRA+136 μM SM combination led to 5- and 2-fold increases in the CASP3 gene expression, respectively . The B16F10 cells treated with 136 μM of SM significantly overexpressed the Bax gene by 6 times , whereas the 123 μM ATRA+136 μM SM combination resulted in a 5-fold increase in the Bax gene expression (p ≤ 0.001) . However, 123 μM of ATRA alone did not change the relative Bax gene expression . On the other hand, the 123 μM ATRA+136 μM SM combination led to 0.13-fold and 0.5-fold (p ≤ 0.001) decreases in the PD-L1 gene expression in the B16F10 cells, respectively . In addition, treatment of the B16F10 cells with 123 μM of ATRA, 136 μM of SM, and the 123 μM ATRA+136 μM combination resulted in 6-fold (p ≤ 0.01), 17-fold , and 13-fold (p ≤ 0.001) increases in the CDKN2A gene expression, respectively, as depicted in Figure 5D . Section title: Discussion Educational score: 4.369278430938721 Domain: biomedical Document type: Study Language: en ATRA has been widely studied as a potent inhibitor of growth in melanoma cancer cells and displays very strong antineoplastic activity through the inhibition of cell proliferation, and induction of apoptosis in the cancer cells . Although ATRA indicates the efficacy in melanoma cells, it has some limitations, including the decrease in the concentrations due to its very short plasma pharmacokinetic profile, high volume of distribution, and excessive binding to tissues, thus leading to pharmacological limitations in its clinical use in cancer . Similarly, SM has recently garnered much attention in the cancer investigations due to its potential anticancer effects as tumor-suppressing biologically active lipids . However, the fast metabolic interconversions, and signaling functions occurring inside the biological membranes of sphingolipids pose biochemical and biophysical complexities when attempting to determine the precise roles of ceramides in the regulation of apoptosis. Furthermore, additional research is needed to investigate the potential modifications in sphingolipid signaling that could enhance immune cell (specifically macrophages) antitumor capabilities to improve the efficacy of immunotherapy in combating cancer. To address the limitations, a unique therapeutic approach involving the combination of ATRA and SM was devised herein for the treatment of melanoma, which has not been previously reported. The results demonstrated that the concomitant administration of ATRA and SM led to a substantial augmentation in anticancer activity, as evidenced by a notable decrease in the viability of the B16F10 melanoma cells with relatively less toxicity on the macrophages. Section title: Discussion Educational score: 4.596379280090332 Domain: biomedical Document type: Study Language: en Cell viability data indicated that the combination of 123 μM of ATRA and 136 μM of SM significantly inhibited the cell proliferation of the B16F10 cells at 72 h in a time-dependent manner . Furthermore, the combinational therapy improved the safety features of the ATRA and SM on the macrophages, in which the RAW264.7 viability was as high as 85.42% at 72 h of incubation with the 123 μM ATRA+136 μM SM combination compared to the standalone treatment of ATRA and SM . At 48 h of incubation with 100 μM of ATRA, the viability of the melanoma cells was approximately 80%, indicating consistency with the value in the literature (i.e. 70%–75% and 85%) for MCF7 breast and HCT116 colon cancer cells, respectively . In addition, Bidad et al. reported that ≤10 μM of ATRA had no significant impact on cell viability and proliferation. The IC 50 (123 ± 0.02 μM) and CC 50 (99.54 ± 1.55 μM) values of the ATRA indicated a selectivity of 0.81 for the B16F10 cells compared to the RAW264.7 cells . Previously, the effect of ATRA on the SM cycle was researched through SMase expression on MCF-7 (ATRA-sensitive) breast cancer cells, in which an increase in SMase activity was observed in the MCF-7 cell line in an ATRA-sensitivity-dependent manner . Clarke et al. reported that growth arrest in ATRA-induced MCF-7 breast cancer cells was mediated by SMase expression, and estrogen receptor-positive MCF-7 cells were employed as a model system to investigate the involvement of nSMase2 and sphingolipids in the growth arrest produced by ATRA. The underlying anticancer mechanism of the SM could be explained as the breakdown of SM by the SMase to produce ceramide after ATRA stimulation . Moreover, ceramide can also be used as a substrate for the generation of complex sphingolipids via conversion to glucosylceramide by glucosylceramide synthase . In terms of the anticancer mechanism, ceramide, a bioactive lipid, is thought to induce death, growth inhibition, and senescence in cancer cells, where classic mitochondria-dependent apoptosis was reported to be triggered by endogenous and exogenous ceramide signaling via ceramide-activated Ser-Thr protein phosphatases (CAPPs) and the expression of tumor suppressor genes (e.g., p38, Bax) . In addition, the effect of ceramide on CAPPs resulted in the inactivation of the antiapoptotic kinase AKT via protein dephosphorylation, and thus the downgrading of AKT by several signals (protein phosphatase 2A, protein kinase Cζ, and p38) decreases the phosphorylation of B-cell lymphoma 2 in intrinsic apoptosis . Section title: Discussion Educational score: 4.123594284057617 Domain: biomedical Document type: Study Language: en In line with the cell viability analysis, distinct morphological alterations were detected in terms of cell shrinkage, acquisition of a spherical form, and aggregation, as indicated by previous research , suggesting the signs of apoptosis. Treatment with ATRA and SM resulted in the transformation of cells to round-shaped cell morphologies, which was attributed to the loss of integrity and detachment of the B16F10 cells induced apoptosis . Section title: Discussion Educational score: 4.334063529968262 Domain: biomedical Document type: Study Language: en Parallel to the cell viability and morphological analysis, the cell cycle results suggested that the higher concentrations of ATRA and SM (i.e. ≥100 μM), alone, could alter the cell cycle frequencies at 24 h of treatment, thus inducing G0/G1 arrest in the B16F10 melanoma cells . The increase in the cell population in the G0/G1 phase and the induction of the cell cycle arrest by ATRA and ceramides alone in the cancer cells were compatible with the literature . Similar to ATRA, another study stated that the addition of ceramide in human leukemic cell lines (e.g., MOLT-4) caused cell cycle arrest in the G0/G1 phase, and cell cycle progression, accompanied by an increase in ceramide levels resulting from the breakdown of SM . On the other hand, the contribution of ceramide in the G0/G1 arrest was closely linked to the role of nSMase2 in facilitating growth arrest triggered by confluence . Clarke et al. demonstrated that nSMase2, a key ceramide-producing enzyme involved in cellular stress responses, plays a role in ATRA-induced growth arrest induced by ATRA in MCF7 cells. The observed phenomenon was ascribed to the dephosphorylation of β-catenin through the involvement of a protein phosphatase 1-γ, indicating the presence of a signaling mechanism that mediates this particular action . Recent research has elucidated the role of dihydroceramide in regulating G0/G1 arrest triggered by cell confluence in neuroblastoma . Section title: Discussion Educational score: 4.4367570877075195 Domain: biomedical Document type: Study Language: en On the other hand, codelivery of ATRA with SM reduced the cell population in the G0/G1 phase in terms of G0/G1-phase cell cycle arrest, while leading to increased G2/M phase cell populations at 24 h . Previously, it was reported that ATRA treatment stimulates the conversion of SM into ceramides, an anticancer metabolite, by the induction of the SMase enzyme . Since ceramide induces apoptosis, cell differentiation, and senescence, the combination of SM and ATRA could be used as an anticancer agent by stimulating the ceramide accumulation mechanism. In addition, ceramide may have an involvement in regulating the G2/M cell cycle checkpoint . Previously, it was observed that the introduction of threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol, an inhibitor of glucosylceramide synthase, resulted in an increase in the levels of ceramide in NIH 3T3 cells . The increase in ceramide levels was attributed to a decrease in the cyclin-dependent kinase CDK1 activity, thus resulting in G2/M cell cycle arrest . The observed phenomenon in the current study can be ascribed to the arrest of the cell cycle in the G2/M phase following the combinational treatment of 123 μM ATRA+136 μM SM. Similarly, the modulation of G2/M arrest induced by the chemotherapeutic drug paclitaxel was observed by Espaillat et al. , when β-glucosidase was knocked down, leading to the inhibition of ceramide formation . Elevation in ceramide levels has been documented to take place immediately during the G2/M transition in order to modulate the dephosphorylation of retinoblastoma (Rb) . Moreover, recent studies have indicated that ceramide could produce G2/M arrest in rhabdomyosarcoma cells. Section title: Discussion Educational score: 4.4165849685668945 Domain: biomedical Document type: Study Language: en The observation of elevated levels of CASP3 expression was consistent with the data obtained from the Annexin V FITC/PI flow cytometry analysis , indicating the incidence of higher cell death when the B16F10 cells were treated with the 123 μM ATRA+ 136 μM SM combination . Likewise, the CDKN2A gene was upregulated in the B16F10 melanoma cells when treated with 123 μM of ATRA, 136 μM of SM, and the 123 μM ATRA+136 μM SM combination, indicating consistency with the literature, in which germ-line mutations in the CDKN2A tumor-suppressor gene were related to the pathogenesis of hereditary melanoma, specifically concerning the development of melanoma. In addition, the gene CDKN2A is responsible for producing a cell-cycle regulator by suppressing the actions of CDK4 and CDK6, which are protein kinases that subsequently phosphorylate the Rb protein . Herein, overexpression in the CDKN2A was correlated with apoptosis after the ATRA and SM combinational treatment in the melanoma cells, thus inducing tumor suppression and reduction in cell viability. On the other hand, the PD-L1 gene was downregulated in the B16F10 cells following treatment with 136 μM of SM and the 123 μM ATRA+136 μM SM combination , verifying the results of previous studies in which ATRA exerted a suppressive effect on the expression of the PD-L1 gene in cellular systems . Interestingly, 123 μM of ATRA alone did not lead to an alteration in the expression of the PD-L1 gene in B16F10 melanoma cells . Recently, there have been effective applications of novel medicines that specifically target the surface expression of programmed cell death-1 (PD-1)/PD-L1 in the treatment of various solid malignancies, such as melanoma . The expression of PD-L1 has been linked to the occurrence of tumor metastases, the advancement of tumors, and worse prognosis. The downregulation of the PD-L1 gene in the combinational treatments could be attributed to the increased tumor suppression and cell cycle arrest on melanoma cells. Overall, the findings of the cell cycle and apoptosis were supported by an investigation of the mRNA expression levels. Section title: Discussion Educational score: 4.148908615112305 Domain: biomedical Document type: Study Language: en The combinational ATRA + SM treatment had a significant effect on cell proliferation and cell differentiation in melanoma cells, hence triggering apoptosis and causing cell cycle arrest. The combinational use of of 123 μM ATRA + 136 μM SM reduced cell viability, induced apoptotic cell death, caused cell cycle arrest, and overexpressed the Bax, CDKN2A, and CASP3 genes . Section title: Conclusion Educational score: 4.156989097595215 Domain: biomedical Document type: Study Language: en In summary, the hypothesis herein proposed that the concurrent use of two therapeutic components would augment the effectiveness of anticancer treatment in the treatment of B16F10 melanoma cancer cells, indicating the synergistic effects of this innovative treatment strategy. The findings provided evidence that the concurrent application of ATRA and SM results in a significant enhancement in anticancer efficacy, as indicated by a considerable reduction in the viability and proliferation of B16F10 melanoma cells with relative toxicity on RAW264.7 macrophages. The observed increase implies a possible interaction between the molecular pathways affected by ATRA and SM, resulting in a combined effect that exceeds the effects of each treatment on its own regarding the induction of apoptotic cell death, and cell cycle arrest on B16F10 cells. Section title: Conclusion Educational score: 4.016571044921875 Domain: biomedical Document type: Study Language: en The promising efficacy of the ATRA and SM combination in an in vitro model demonstrated remarkable efficacy, indicating its potential for future in vivo and clinical investigations in anticancer therapy. It is important to underscore that this study represents the first report revealing the combination of ATRA and SM enhancing the anticancer therapy on B16F10 melanoma cells. | Review | biomedical | en | 0.999998 |
PMC11698199 | Section title: Introduction Educational score: 4.639923095703125 Domain: biomedical Document type: Review Language: en MEIS genes, part of the TALE superclass of homeodomain proteins, are transcription factors crucial for diverse biological processes, such as development and tissue-specific gene expression . The MEIS gene family includes members like Meis1, Meis2, and Meis3 with multiple isoforms through alternative splicing . In recent years, there has been a growing acknowledgment of the crucial role played by MEIS proteins and their associated counterparts in a wide array of biological processes, spanning regeneration , stem cell functionality , cellular metabolism , tumor development , and modulation of lifespan. Notably, MEIS1 is essential for cardiac development and hematopoiesis , MEIS2 plays key roles in limb and eye development with relevance to neurodevelopmental disorders , and MEIS3, while less explored, contributes to specific developmental contexts . MEIS proteins play essential roles in critical pathways like HOX , Wnt , and Hedgehog signaling , exerting influence over body segment identity, limb development, neural tube formation , heart development , and eye development . Grasping the multifaceted functions of MEIS proteins in these pathways and their therapeutic modulation is of substantial relevance for the field of regenerative medicine and provides valuable perspectives into the underlying causes of developmental abnormalities and congenital disorders. Section title: Introduction Educational score: 4.476988792419434 Domain: biomedical Document type: Study Language: en Our recent research has been dedicated to developing MEIS1 inhibitors, capitalizing on our specialized tools and expertise in MEIS1 biology . Two recently identified MEIS1 small-molecule inhibitors, namely MEISi-1 and MEISi-2, have demonstrated the ability to enter cells and produce dose-dependent effects. Importantly, they operate by disrupting the interaction between the MEIS1 homeodomain and target DNA, thereby impairing the activation of MEIS1-targeted gene expression, including Hif-1α, Hif-2α, and p21. Furthermore, they show promise in expanding and enhancing the self-renewal potential of human and murine hematopoietic stem cells in vitro and in vivo. In addition, recent knockout studies in animal models showed that the elimination of Meis1 in adult cardiomyocytes triggers an increase in cardiomyocyte proliferation . Research has revealed that Meis1 plays a crucial role in the transcriptional network governing cardiomyocyte cell cycle, hematopoietic stem cell maintenance, and cellular metabolism. These discoveries imply that Meis1 holds promise as a therapeutic target for a range of conditions, including modifying cancer metabolism, targeting cancer stem cells, expanding HSC populations, and promoting cardiac regeneration and possibly preventing cardiotoxicity . Section title: Introduction Educational score: 4.437687397003174 Domain: biomedical Document type: Study Language: en Cardiotoxicity encompasses a spectrum of adverse effects on the heart due to drugs or other agents, which can lead to heart damage , arrhythmias , and cardiomyopathy . In severe cases, it may result in heart failure . This condition is particularly important in clinical medicine and drug development, notably in oncology, where some treatments have cardiotoxic effects, necessitating careful patient monitoring and potential treatment limitations . The downregulation of MEIS1 is associated with the enhanced maturation of oxidative phosphorylation during perinatal cardiomyocyte development, while Meis1 exerts inhibitory effects on angiotensin II-induced cardiomyocyte hypertrophy. Additionally, the restoration of Meis1 expression leads to improved electrophysiological function in cardiomyocytes . Here we investigated MEIS1’s pivotal role in regulating cardiomyocyte cell cycle arrest as a promising therapeutic target. We aimed to provide a compelling pathway for enhancing cardiomyocyte renewal through MEIS1 inhibition. This is supported by investigations involving neonatal cardiomyocytes, wherein two novel small molecules, MEISi-1 and MEISi-2, are used to stimulate neonatal and adult cardiomyocyte proliferation and cytokinesis by downregulating MEIS target genes and cyclin-dependent kinase inhibitors (CDKIs). Additionally, the study included the effect of MEIS1 inhibition in early development via the cultivation and differentiation of human induced pluripotent stem cells (hiPSCs) into cardiomyocytes. Section title: Introduction Educational score: 3.802560567855835 Domain: biomedical Document type: Study Language: en These findings could underscore the potential of MEIS inhibitors as a key regulator of cardiac gene expression, emphasizing their promise as therapeutic agents in regenerative cardiology. Section title: Isolation of rat neonatal ventricular cardiomyocytes Educational score: 4.2100067138671875 Domain: biomedical Document type: Study Language: en This protocol was conducted as previously described . Hearts were extracted from 1- to 2-day-old rat pups after decapitation. To avoid contamination, the hearts were briefly immersed in ethanol within a sterile hood before being placed in an enzyme solution for digestion. Only the ventricular portion of the heart was dissected and it was placed in the enzyme solution. The enzyme solution consisted of 0.1% Pancreatin, and 50 mL of the solution was used for each batch. Subsequently, the hearts were incubated at 37 °C for 20 min with gentle agitation at 100–120 rpm, followed by centrifugation at 2000 rpm for 10 min. To remove fibroblast cells in the pellet, the isolated ventricular cardiomyocytes were seeded into a specialized cell culture medium and incubated at 37 °C for 2 h. After the cells were gently collected, they were filtered through a 70–100 μm cell strainer and seeded in a cell culture medium precoated with gelatin, consisting of myocyte medium (3:1 DMEM: M199, Pen/Strep, L-Glutamine (2 mM), 10% normal rat serum, 5% FBS) at a density of 500,000 cells/mL and placed in a 37 °C incubator with 5% CO 2 . Section title: 2.2. Immunostaining in cardiomyocytes Educational score: 4.167797088623047 Domain: biomedical Document type: Study Language: en This protocol was conducted as previously described . Cardiomyocytes were expanded to a density of 50%–70% (5 × 10 5 cells/6-well plates). They were treated with putative Meis1 inhibitors (0.1, 1, and 10 μM concentrations), and an increase in cardiomyocyte division rates was assessed by examining the levels of Ph3, AuroraB, and TnnT in the cells after 3–5 days. Immunostaining was conducted for this purpose. Following applications of putative Meis1 inhibitors, cardiomyocytes were fixed with 4% PFA (10 min at room temperature). Subsequently, the cells were permeabilized with 0.1% Triton X-100 for 15 min at room temperature. The cells were then blocked with 1% normal bovine serum (for 30 min) after washing. Next, the cells were incubated at room temperature with antibodies for phospho-histone H3 (PH3) (cell division marker, Ser10, 1:250 dilution, rabbit polyclonal, Millipore), Aurora B (cytokinesis marker, 1:250 dilution, rabbit polyclonal, Sigma), and cardiac troponin T (TnnT2) (cardiomyocyte marker, Thermo Scientific MS-295-P1, 1:200 dilution, mouse monoclonal). Detection was performed using secondary antibodies such as Alexa Fluor 488 donkey anti-mouse and Alexa Fluor 555 donkey anti-rabbit (Invitrogen, 1:400 dilution), along with Hoechst 33342 (Invitrogen) DNA dye. The number of Ph3+TnnT2+ and AuroraB+TnnT2+ cardiomyocytes was determined using the GE Cytell imaging system. Section title: 2.3. Isolation of adult cardiomyocytes from mice heart Educational score: 4.0759687423706055 Domain: biomedical Document type: Study Language: en To isolate adult ventricular cardiac cells, we followed a previously described method , starting with the treatment of adult cardiac tissue with collagenase. For the collection of pure and viable ventricular cardiomyocytes from adult mouse hearts, we utilized the EASYCELL-CM system from Harvard Apparatus. Following enzymatic perfusion of the heart, the cells were gathered and allowed to undergo gravity settlement. Within just 5 min, a pellet formed, which contained the cardiomyocytes. These cardiomyocytes were isolated and examined under a microscope. Section title: 2.4. Primary cardiac fibroblast isolation and culture from adult mouse heart Educational score: 3.975705862045288 Domain: biomedical Document type: Study Language: en EASYCELL-CM and enzymatic processes allowed us to obtain both fibroblasts and cardiomyocytes. To separate the fibroblasts from the cardiomyocytes, we employed PRIMARI cell plates. The solution containing the fibroblasts was then seeded into two separate PRIMARI cell culture dishes (10 cm each), where the adhering fibroblasts were allowed to grow for 3–5 days in the cell culture. Section title: 2.5. Viability assay in primary cardiac fibroblasts Educational score: 4.103062629699707 Domain: biomedical Document type: Study Language: en Cardiac fibroblasts were cultured in a 20% FBS DMEM medium and seeded in a 96-well plate with 5000 cells per well, allowing them to attach over 24 h. Subsequently, MEISi-1 and MEISi-2 compounds were introduced to the cells at about 5 μM for each well. The cells were then incubated at 37 °C for 72 h. Following the incubation period, MTS solution was introduced to the cell cultures and left to incubate for 2 h under standard culture conditions. Absorbance measurements were recorded at 490 nm using a microplate reader (Thermo Fisher Multimode Reader Varioskan Lux). To obtain accurate readings, the absorbance of the blank group was subtracted from the absorbance values of the samples. Section title: 2.6. IPSC culture and CM differentiation Educational score: 4.225706100463867 Domain: biomedical Document type: Study Language: en hiPSCs , generously provided by the Köse Lab at Yeditepe University, were cultured at 37 °C with regular medium changes. Cells were passaged every 3 to 4 days, maintaining 80%–90% confluence . Passaging involved aspirating the medium, adding Versene, and transferring detached cells to Matrigel-coated plates at a 1:13 split ratio, with daily medium changes. Matrigel coating was prepared at 1.2 mg/mL in cold RPMI-1640, and the coated plates/flasks could be stored for up to 3 weeks. In the hiPSC-cardiomyocyte differentiation, we began with CDM3 + 6 μM CHIR on day 0, followed by CDM3 + 2 μM IWP2 on day 2, and continued with CDM3 medium until day 13 when cardiomyocytes were ready for expansion. Replating of differentiated hiPSC derived cardiomyocytes, suitable for cardiac expansion, occurred between days 10 and 14. This involved incubating cells with TrypLE Select, counting and replating them at a 1:10–20 split ratio in the desired culture system. Incubation was at 37 °C, 5% CO 2 , 21% O 2 , and 90% humidity, with gentle movements for even cell distribution. Section title: 2.7. Flow cytometric analysis in hiPSC-derived cardiomyocytes Educational score: 4.199889659881592 Domain: biomedical Document type: Study Language: en To evaluate the quality and expansion rates of hiPSC-derived cardiomyocytes, the cells underwent a series of procedures. Initially, the cells were gathered, fixed, and subjected to immunocytochemical staining for the cardiac markers α-actinin and troponin-T. Subsequently, the cardiomyocytes were dissociated. Following cell counting, 100,000 cardiomyocytes were collected in 1.5-mL tubes and centrifuged at 200 × g for 3 min. The supernatant was then discarded, and 50 mL of 4% PFA solution was added to each tube for a 10-min incubation period. The cells were later resuspended at a concentration of 1 × 10 5 cells in 50 mL of permeabilization buffer containing 5% BSA and 0.3% Triton X-100, and incubated for 30 min at 4 °C. Afterwards, the resuspended cardiomyocytes were placed in 50 mL of flow cytometry buffer, along with α-actinin antibody (1:300 dilution), troponin-T antibody (1:300 dilution), and a negative control containing 1 × 10 5 cells in 50 mL of flow cytometry buffer. This mixture was incubated for 30 min at 4 °C. The cells underwent subsequent washing steps, including centrifugation at 200 × g for 5 min at 4 °C, with the supernatant being discarded and the washing process conducted twice. The final step involved resuspending the cells in 50 mL of flow cytometry buffer containing secondary antibodies (goat anti-mouse and goat anti-rabbit, both at 1:300 dilution) for analysis using a flow cytometer. Section title: 2.8. RT-PCR analysis of hiPSC differentiation into cardiomyocytes Educational score: 4.045814514160156 Domain: biomedical Document type: Study Language: en Total RNA was prepared using the RNeasy Kit (Qiagen) and reverse-transcribed with the iScript cDNA Synthesis Kit (Bio-Rad) using random primers. qRT-PCR was performed using the i-Taq SBR Green Master Mix (Bio-Rad). The expression levels of the target genes were normalized to GAPDH levels ( Table 1 ). Section title: 2.9. Cell viability assay in hiPSCs Educational score: 4.1010637283325195 Domain: biomedical Document type: Study Language: en hiPSCs were grown in m-TESR1 complete medium supplemented with 10 mM Y27632 and were seeded in a 96-well plate with 5000 cells per well and left for 24 h to attach. MEISi-1 was dissolved in dimethyl sulfoxide (DMSO) as a 100 mM stock solution. The molecule was then delivered to the cells at the various increased doses of MEISi-1 (10 nM up to 5 μM) for each well and incubated at 37 °C for 72 h. After incubation, MTS solution was added to the cells and incubated for 2 h under standard culture conditions. Absorbance was measured at 490 nm using a microplate reader (Multimode Reader Varioskan Lux, Thermo Fisher). The absorbance of the blank group was subtracted from the absorbance of the samples. Section title: 2.10. Long-term and short-term MEISi-1 treatment of hiPSCs Educational score: 4.12071418762207 Domain: biomedical Document type: Study Language: en The hiPSCs were thawed and seeded onto Matrigel-coated six-well plates at a cell density of 0.8 × 10 4 cells/cm 2 in mTeSR1 medium for 4 days. Afterward, the hiPSCs were treated with 5 μM MEIS inhibitor (MEISi) for 18 days, with medium changes every 2 days. From day 10 onwards, the experiment was continued without further medium changes for an additional 8 days. On day 18, the cells were collected for qPCR experiments. Section title: 2.10. Long-term and short-term MEISi-1 treatment of hiPSCs Educational score: 4.186760425567627 Domain: biomedical Document type: Study Language: en In the short-term MEISi treatment method, hiPSCs are initially cultured on Matrigel-coated 6-well plates for 4 days using mTesR medium with the same density of cells. Subsequently, to induce mesoderm progenitor cell formation, a 6 μM GSK3 inhibitor (CHIR) is introduced in a differentiation medium containing RPMI, ascorbic acid, and albumin, and the cells are left to incubate for 48 h. After this stage, the differentiation medium (CMD3) is prepared, supplemented with WNT inhibitor (IWP2) and MEIS inhibitor1, and the cells are cultured for an additional 3 days to promote the differentiation of cardiac mesoderm and cardiac progenitor cells. Throughout the process, cellular changes are monitored with a qPCR experiment to investigate whether MEIS inhibitors play a role similar to WNT inhibitors in guiding mesoderm cells towards a cardiac mesoderm or cardiac progenitor cell fate. Section title: 2.11. Analysis of cardiac tissue post-MEIS injections Educational score: 4.130942344665527 Domain: biomedical Document type: Study Language: en To assess the expression of ventricular cardiomyocyte cell cycle regulators in cardiac tissue, we employed real-time qPCR following MEISi-1 and MEISi-2 injections into the animals, as outlined in our previous study . Whole cardiac tissue samples were collected and half of them subsequently powdered in liquid nitrogen using a mortar. Half of the cardiac tissue was used for parafilm sectioning and TnnT/Ph3 immunohistochemistry studies as outlined previously (. RNA isolation was performed using the TRIzol method. RNA concentration was determined with a NanoDrop (Thermo Fisher). For each tissue sample, 5 μg of RNA was converted into cDNA using random primers and the ProtoScript II First Strand cDNA Synthesis Kit (NEB, Cat. No: E656). Subsequently, the samples were stored at −20 °C after dilution. Gene-specific primers ( Table 2 ) were selected using NIH primer depot ( http://mouseprimerdepot.nci.nih.gov ) and ordered from Sentebiolab in Türkiye. The desired gene regions were then amplified from the cDNAs using a Bio-Rad FX96 Touch Real-Time qPCR Detection System, following the cycling conditions of 95 °C for 10 min, 95 °C for 10 s, 60 °C for 20 s, and 72 °C for 30 s (30 cycles). The expression of each amplified potential modulator gene was normalized against the GAPDH content using the ΔΔCt method. Section title: 2.12. Anesthesia Educational score: 4.1370086669921875 Domain: biomedical Document type: Study Language: en The mice were anesthetized as previously reported . In brief, they were placed in an induction chamber (Hugo Sachs Electronik) and 2%–3% vol/vol isoflurane delivered by 95% oxygen (1 L/min) was administered. After establishing narcosis, the mice were transferred to a surgical platform (Kent Scientific), equipped with a temperature control module (Kent Scientific), and fixed in a supine position with a rectal probe inserted for temperature maintenance at 37 °C throughout the entire procedure. The isoflurane concentration was regulated at 1.5% vol/vol using a vaporizer (Hugo Sachs Electronik) to maintain narcosis. Fentanyl (0.05 mg/kg body weight) was injected intraperitoneally for analgesia in the beginning of the experiment; additional doses (0.025 mg/kg) were given every 45 min. Depth of anesthesia was evaluated by the toe pinch reflex. Subsequently, once a negative response in the toe pinch reflex was confirmed, we could initiate the following experiments. Section title: 2.13. Echocardiography Educational score: 4.132216453552246 Domain: biomedical Document type: Study Language: en Echocardiographic studies were conducted using a VEVO-2100 Imaging ultrasonographic system (VisualSonic, Toronto, Canada) at a resolution of 100 dpi. After anesthesia induction, a 12.5 MHz transducer was applied to the left hemithorax and two-dimensional M-mode images from the short-axis view were acquired. LV end-diastolic and end-systolic diameters, as well as LV anterior and posterior wall thicknesses, were measured using the leading-edge convention of the American Society of Echocardiography. The LV ejection fraction (EF) percentage was computed as EF (%) = (LVIDd3-LVIDs3) / LVIDd3 × 100, where LVIDd3 and LVIDs3 represent LV end-diastolic and end-systolic diameters, respectively. Section title: 2.14. ECG Educational score: 4.043079376220703 Domain: biomedical Document type: Study Language: en Following anesthesia induction, three subcutaneous needle electrodes (29 G, AD Instruments) were inserted in both the upper and left lower limbs of the mice to allow recording of a Lead I ECG. To record and analyze ECGs, an amplifier (AD Instruments), a PowerLab system (AD Instruments), and LabChart Pro software (AD Instruments) were used. The ECG data were derived from 5-min recordings. Section title: 2.15. Statistical analysis Educational score: 3.412217855453491 Domain: biomedical Document type: Study Language: en The data are presented as the mean ± standard error of the mean (SEM). Significance levels were determined using a two-tailed Student’s t-test and one-way ANOVA. Statistical significance in the echocardiography data was evaluated using the two-sided Mann–Whitney test. Statistical significance was ascribed to results with p-values less than 0.05. Section title: 2.16. Approvals Educational score: 0.8106350302696228 Domain: biomedical Document type: Other Language: en All animal and human studies are approved by the local institutions of Yeditepe University, İstanbul, Türkiye (Ethical Committee Approval #673) and LMU Munich, Munich, Germany. Section title: 3.1. MEIS1 inhibitors stimulate cardiomyocyte proliferation and cytokinesis Educational score: 4.113286018371582 Domain: biomedical Document type: Study Language: en To investigate the dynamics of cell division within cardiomyocytes, we employed rat neonatal cardiomyocytes (RNCMs) as a model system . Then cellular division events were meticulously examined using immunostaining techniques. Upon successful isolation of RNCMs, they were cultured in 96-well plates and subjected to a progressive gradient of MEIS1 inhibitors at concentrations of 0.1, 1, and 10 μM. Following a 3-day incubation period, the cardiomyocytes were fixed and subsequently subjected to immunostaining using antibodies targeting specific markers: TnnT2 for cardiomyocytes, Ph3 for proliferation, and AuroraB for cytokinesis. Section title: 3.1. MEIS1 inhibitors stimulate cardiomyocyte proliferation and cytokinesis Educational score: 4.094943046569824 Domain: biomedical Document type: Study Language: en The research analysis was primarily centered on quantifying actively dividing cardiomyocytes, defined as TnnT2+Ph3+. In addition, an evaluation of cytokinesis rates was conducted by examining TnnT2+AuroraB+ markers . Our findings revealed a substantial augmentation in both the proportion and number of TnnT2+Ph3+ cardiomyocytes , demonstrating an increase of up to 2.5 times. Moreover, a similar enhancement, amounting to a twofold increase, is clearly observed in the population of cardiomyocytes undergoing cytokinesis subsequent to MEIS1 inhibitor treatment, as visually represented in Figures 1E–1G . Section title: 3.1. MEIS1 inhibitors stimulate cardiomyocyte proliferation and cytokinesis Educational score: 4.068603038787842 Domain: biomedical Document type: Study Language: en In conclusion, our study using neonatal rat cardiomyocytes and MEIS1 inhibitors demonstrated a substantial increase in actively dividing cardiomyocytes and those undergoing cytokinesis. These findings shed light on the potential for regulating cardiomyocyte division and offer valuable insights into the potential mechanisms that could be harnessed for cardiac regeneration and repair in the adult heart. Section title: 3.2. MEIS1 inhibitors promote adult ventricular cardiomyocyte proliferation and may inhibit fibroblast growth Educational score: 4.112496376037598 Domain: biomedical Document type: Study Language: en Cardiomyocytes in the adult heart often enter a quiescent state, displaying limited participation in the active cell cycle. To explore the dynamics of cell division within adult cardiac tissue, adult ventricular cardiomyocytes as well as noncardiomyocytes were isolated and cultured, and MEIS1 inhibitors at concentrations of 5 μM were applied. After a 3-day incubation period, immunostaining was performed using TnnT2 for cardiomyocytes and Ph3 for proliferation . Section title: 3.2. MEIS1 inhibitors promote adult ventricular cardiomyocyte proliferation and may inhibit fibroblast growth Educational score: 4.089354991912842 Domain: biomedical Document type: Study Language: en Our findings demonstrate a significant increase in the number of noncardiomyocytes (TnnT2-Ph3+) and cardiomyocytes (TnnT2+Ph3+) post-MEISi-2 treatments only. MEISi-1 did not show any effect on the proliferation of primary ventricular cells . Next, we assessed the effect of MEIS1 inhibitors in cultured cardiac fibroblasts . Intriguingly, both MEISi-1 and MEISi-2 treatments reduced cardiac fibroblast proliferation in vitro . Section title: 3.2. MEIS1 inhibitors promote adult ventricular cardiomyocyte proliferation and may inhibit fibroblast growth Educational score: 4.0492939949035645 Domain: biomedical Document type: Study Language: en In conclusion, our research conducted with adult cardiac tissue and the application of MEIS1 inhibitors underscores a significant augmentation in actively dividing ventricular cardiomyocytes and suggests the potential inhibition of fibroblasts originating from adult tissue. Section title: 3.3. Expression of Meis1/2 increased after cardiac differentiation of human IPSCs Educational score: 4.144600868225098 Domain: biomedical Document type: Study Language: en Next we wanted to assess if MEIS expression plays a role in cardiac differentiation in hiPSCs. To induce cardiac differentiation in these cells, we employed a strategic approach utilizing GSK3 and WNT inhibitors, as delineated in Figure 3A . These cells were cultured on Matrigel-coated six-well plates and maintained in mTeSR1 medium for 4 days. The differentiation process commenced with the introduction of CDM3 medium and CHIR99021 over 48 h, leading to the emergence of Brachyury-expressing cells. Subsequently, we introduced the IWP2 inhibitor for an additional 48 h to guide the cells towards a cardiac fate. The culture medium was refreshed every 2 days, and functional contracting cardiomyocytes were observed after 13 days . This was evident with the proportions of TnnT+ and actinin+ cells in hiPSC derived cardiomyocytes . Section title: 3.3. Expression of Meis1/2 increased after cardiac differentiation of human IPSCs Educational score: 4.170499801635742 Domain: biomedical Document type: Study Language: en We conducted an in-depth examination of gene expression patterns through real-time reverse-transcription PCR (RT-PCR). Our findings were consistent with established differentiation strategies and embryonic development principles. We observed a rapid downregulation of pluripotency markers OCT4, TERT, and Sox2, concomitant with the upregulation of cardiac mesoderm markers ISL1 and Brachyury . Notably, both early and late cardiomyocyte markers Nkx2.5 and TNNT2 exhibited robust expression, as depicted in Figure 3D . Furthermore, it is noteworthy that Meis1 and Meis2 displayed significant upregulation . Section title: 3.3. Expression of Meis1/2 increased after cardiac differentiation of human IPSCs Educational score: 3.966721773147583 Domain: biomedical Document type: Study Language: en In summary, the findings suggest that the upregulation of Meis1 and Meis2 genes following cardiac differentiation of hiPSCs underscores their significant roles in cardiac development. Section title: 3.4. Effect of long-term and short-term MEIS1 inhibition in hiPSC differentiation Educational score: 4.0870161056518555 Domain: biomedical Document type: Study Language: en We initially assessed whether inhibiting the MEIS pathway resulted in any cytotoxicity for iPSCs. To this end, we assessed hiPSCs’ cell viability and mitochondrial activity post-MEISi-1 treatments using the MTS tetrazolium assay. These experiments, which included a range of MEISi-1 doses, did not show significant changes in mitochondrial activity or cell viability compared to the control group treated with DMSO, the solvent for the MEIS1 inhibitor . Then the MEIS1 inhibitor treatment protocol was designed to explore the impact of MEISi-1 on hiPSCs and monitor gene expression alterations throughout the experiment . The hiPSCs were initially grown on Matrigel-coated plates and then subjected to MEISi-1 for an extended duration, with routine medium changes up to day 10. Following this, the medium remained unchanged for the subsequent 8 days. Cells collected on day 18 were employed for qPCR analysis, facilitating the assessment of gene expression profiles influenced by MEIS1i treatment. Section title: 3.4. Effect of long-term and short-term MEIS1 inhibition in hiPSC differentiation Educational score: 4.185795783996582 Domain: biomedical Document type: Study Language: en We observed that MEIS1 inhibition results in the upregulation of pluripotency markers, including TERT, OCT4, and Sox2 expression following MEISi-1 treatments in comparison to the control (DMSO). Additionally, cardiac mesoderm markers ISL1 and Brachyury exhibited increased expression, indicating increased mesodermal differentiation after MEISi-1 treatments . Conversely, later cardiomyocyte marker TNNT2 showed downregulation post-MEIS1 inhibition, suggesting a hindrance in terminal cardiomyocyte differentiation . Intriguingly, Meis1 and Meis2 exhibited a modest upregulation (16- and 47-fold increases, respectively) , which in turn is a significant downregulation compared to no treatment as seen in the previous study . Section title: 3.4. Effect of long-term and short-term MEIS1 inhibition in hiPSC differentiation Educational score: 4.349757671356201 Domain: biomedical Document type: Study Language: en In the short-term MEISi-1 treatment method, hiPSCs are initially cultured for 4 days. Subsequently, a 6 μM GSK3 inhibitor (CHIR) is introduced into a differentiation medium and the cells are incubated for 48 h to induce mesoderm progenitor cell formation . After this stage, the differentiation medium (CMD3), supplemented with WNT inhibitor (IWP2) and MEIS inhibitor 1 separately, is used for an additional 3-day culture to promote the differentiation from mesoderm stage to cardiac mesoderm . We analyzed the expression of ISL1 , Brachyury , and GATA4 after short-term MEIS inhibition. Interestingly, consistent findings for ISL1 gene expression were observed after short-term MEIS1 inhibition, indicating no significant changes. Another mesoderm marker, Brachyury expression, showed upregulation , highlighting the enhanced mesodermal differentiation under MEIS1 inhibition conditions. Furthermore, GATA4 expression was also notably upregulated, indicating that MEIS1 inhibition plays a pivotal role in promoting mesoderm formation and subsequent cardiac mesoderm commitment. These results collectively demonstrate the positive regulatory effect of MEIS1 inhibition on key cardiac mesoderm markers, underscoring its potential in influencing cardiac differentiation processes. Section title: 3.4. Effect of long-term and short-term MEIS1 inhibition in hiPSC differentiation Educational score: 4.294578552246094 Domain: biomedical Document type: Study Language: en Moreover, analysis of early (Nkx2.5) and late (Tnnt2) cardiac markers expression after short-term MEIS1 inhibition showed notable upregulation in their expression levels. This indicates that the MEIS1 inhibition during the differentiation process had a stimulatory effect on the activation of these cardiac markers. The increased expression of Nkx2.5 and Tnnt2 suggests that MEIS1 inhibition enhances the proper differentiation of cardiac mesoderm progenitor cells and their progression into more mature cardiac cell lineages. These findings highlight the regulatory role of MEIS1 in cardiac development and the potential for MEIS1 inhibitors to positively influence cardiac lineage commitment and maturation. Section title: 3.4. Effect of long-term and short-term MEIS1 inhibition in hiPSC differentiation Educational score: 4.129498481750488 Domain: biomedical Document type: Study Language: en The analysis of various markers, including ISL1, Brachyury, GATA4, Nkx2.5, and Tnnt2, offered insights into the effects of long- and short-term MEIS1 inhibition on hiPSC differentiation. Overall, our findings shed light on the intricate interplay between MEIS1 inhibition and the regulation of pluripotency and cardiac differentiation in iPSCs, providing valuable insights for future research in this field. Section title: 3.5. Investigating the effect of MEIS1 inhibitors on ventricular cardiomyocyte proliferation and gene expression Educational score: 4.093639373779297 Domain: biomedical Document type: Study Language: en These findings suggest that MEIS1 inhibitors may trigger cell cycle activation in ventricular cardiomyocytes, especially due to the decrease in the expression of CDKIs, which negatively regulate the cell cycle. To investigate this, we analyzed cardiac tissue after injection of MEIS1 inhibitors into mice . Studies involved mouse heart tissues to investigate the live imaging effects of Meis1 inhibitors on cardiomyocyte proliferation via immunohistochemistry and expression of CDKIs after serial MEISi-1 and MEISi-2 injections by qPCR . Section title: 3.5. Investigating the effect of MEIS1 inhibitors on ventricular cardiomyocyte proliferation and gene expression Educational score: 4.180752754211426 Domain: biomedical Document type: Study Language: en Immunostaining and quantitative analyses conducted in the left ventricle of mouse hearts following injections of DMSO (control), MEISi-1, and MEISi-2 distinctly demonstrate that MEIS1 inhibitors significantly enhance the proliferation of ventricular cardiomyocytes . Within the left ventricular regions, a remarkable increase in the number of cells labeled with TnnT2+Ph3+ (a proliferation marker) is observed. These findings indicate that MEIS1 inhibitors stimulate the division of ventricular cells, suggesting this process as a promising target for cardiovascular regeneration. Section title: 3.5. Investigating the effect of MEIS1 inhibitors on ventricular cardiomyocyte proliferation and gene expression Educational score: 4.143247604370117 Domain: biomedical Document type: Study Language: en Previous studies demonstrated that the expression of CDKIs decreases in Meis1 knockout experiments, and these inhibitors directly regulate the expression of genes such as p21, Hif-1α, and Hif-2α. Here we examined whether the MEIS1 inhibitors we developed trigger similar gene regulation in cardiac tissue. Following MEISi applications, we observed a reduction in the expression of genes targeted by Meis1, including Hif-2α, and several CDKIs including p16, p18, p19, p19arf, and p27 after both MEISi-1 and MEISi-2 injections . The efficacy of the Meis1 inhibitors MEISi-1 and MEISi-2 became apparent through the observed reduction in Meis1 as well as mRNA expression of the genes targeted by Meis1. Section title: 3.5. Investigating the effect of MEIS1 inhibitors on ventricular cardiomyocyte proliferation and gene expression Educational score: 4.14920711517334 Domain: biomedical Document type: Study Language: en In mouse heart tissue, we observed an increase in ventricular cardiomyocyte proliferation following MEIS1 inhibitor injections. These findings indicate that MEIS1 inhibitors have the potential to activate ventricular cardiomyocyte cell cycles by downregulating CDKIs. The reduced expression of CDKIs and Meis1-targeted genes further supports the effectiveness of these MEIS1 inhibitors, suggesting their promise for promoting cardiac cell division and cardiovascular regeneration. Section title: 3.6. Evaluating the short-term effect of MEIS1 inhibition on cardiac structure and function in vivo Educational score: 4.020395278930664 Domain: biomedical Document type: Study Language: en Given the above results implying a potential role for MEIS1 inhibition in activating cell proliferation in cardiomyocytes, we assessed the impact of MEIS1 inhibition on the heart in vivo. Compared to control mice, MEIS1 inhibitor-treated animals showed a trend towards an increased heart weight and heart weight/tibia length ratio . Section title: 3.6. Evaluating the short-term effect of MEIS1 inhibition on cardiac structure and function in vivo Educational score: 4.037628173828125 Domain: biomedical Document type: Study Language: en To investigate the effects of MEIS1 inhibitor treatment on cardiac dimensions and ejection fraction, echocardiography was performed. LV diameter and ejection fraction, however, were not affected by MEIS1 inhibition . In line with the gross anatomy findings, a nonsignificant trend towards an increased diastolic thickness of the interventricular septum was observed. Section title: 3.6. Evaluating the short-term effect of MEIS1 inhibition on cardiac structure and function in vivo Educational score: 3.928654432296753 Domain: biomedical Document type: Study Language: en To evaluate the potential effects of MEIS1 inhibition on cardiac conduction, ECGs were analyzed . None of the ECG parameters including heart rate, P wave duration, PR interval, QRS duration, or QTc interval was significantly altered after MEIS1 inhibition. Section title: Discussion Educational score: 4.07661247253418 Domain: biomedical Document type: Study Language: en Heart failure is a pervasive medical condition, affecting millions of individuals worldwide. At the heart of its pathophysiology lies the heart’s reduced contractile force, stemming from the replacement of deceased cardiomyocytes, following cardiac events such as ischemia, with noncontractile fibrotic tissue. Although the general mammalian heart is considered incapable of regeneration, a limited number of myocytes do exhibit cell cycling. However, this phenomenon falls short of achieving substantial functional recovery postheart attack. While the mechanisms behind cardiomyocyte cell cycling in adult mammalian hearts remain incompletely understood, the activation of cardiomyocytes is considered a promising strategy for cardiac regeneration. Section title: Discussion Educational score: 4.060831546783447 Domain: biomedical Document type: Study Language: en Research on the development of small-molecule compounds has primarily focused on revealing substances that could facilitate the transformation of various stem cells or progenitors into cardiac cells, rather than concentrating on regulators of the cardiomyocyte cell cycle . Notable among the small molecules discovered for this purpose are those such as SB-203580 , CHIR99021 , ERK , and CamKII inhibitors , which target stem cells and progenitors. These compounds exert their effects on signaling mechanisms like MAPK and GSK-3β . Additionally, there is knowledge that small molecules like NBI-31772 and bromoindirubin-30-oxime (BIO) have a proliferative effect in zebrafish and mammalian heart muscle. However, it is important to note that, thus far, these investigations have not yielded outcomes at the desired level in terms of heart regeneration. This limitation can be largely attributed to the absence of comprehensive tools for studying modulators of mammalian heart regeneration. Section title: Discussion Educational score: 4.276608467102051 Domain: biomedical Document type: Study Language: en The identification of novel cardiogenic factors, such as Meis1, has provided an innovative foundation for the development of treatments targeting the cardiomyocyte cell cycle. Our previous molecular studies have revealed that Meis1 exerts transcriptional influence, turning factors that typically exert a negative impact on the cell cycle, like the p21 and INK4b loci, into positive regulators and negatively affecting cell division in cardiomyocytes . Interestingly, these two gene families are capable of inhibiting the cell cycle at different stages, underscoring the role of cell cycle arrest as the fundamental mechanism in both cardiac cell renewal and the prevention of excessive proliferation in cardiomyocytes. Section title: Discussion Educational score: 4.427237033843994 Domain: biomedical Document type: Study Language: en The majority of studies suggest that in adult cardiomyocytes the levels of CDKIs increase and their activities are associated with positive cell cycle regulators such as cyclins and CDKs . Several studies have demonstrated that Cdk2 and c-myc serve as cell cycle regulators, contributing to the upregulation of CDKs like cyclin CDK4 and CDK4, thereby promoting cardiomyocyte growth . Moreover, the deletion of CDKIs p27Kip1 or p21Cip1 in cardiomyocytes leads to S-phase progression, consequently enhancing cardiomyocyte proliferation and increasing heart size . Recent research has shown that Meis1 deletion induces the upregulation of CDKs and downregulation of CDKIs like p16, p15, p19ARF, p21, and p57 . Additionally, Meis1 deletion results in increased downregulation of positive cell cycle regulators such as MCM3, Chek1, and Ccnd2, and an upregulation of negative cell cycle regulators like APbb1, TP53, and Gpr132 . Targeting Meis1 represents a viable mechanism for inducing cardiomyocyte proliferation. Section title: Discussion Educational score: 4.26357364654541 Domain: biomedical Document type: Study Language: en Research into small molecules that stimulate cardiomyocyte regeneration is advancing rapidly. Our study offers significant insights into the effects of MEIS inhibitors on cardiomyocyte proliferation and gene expression. In neonatal rat cardiomyocytes, MEIS inhibitors significantly increased the number of actively dividing and cytokinesis cells, suggesting their potential for cardiac regeneration. Similarly, in adult cardiac tissue, these inhibitors reactivated the cell cycle, enhancing cardiomyocyte proliferation, and reduced cardiac fibroblast proliferation, impacting noncardiomyocyte cells within the heart. Additionally, investigations with hiPSCs undergoing cardiac differentiation revealed upregulation of MEIS1 and MEIS2, underscoring their roles in cardiac development . Recent research further highlights MEIS2’s role in calcific aortic valve disease (CAVD), where its inhibition promotes osteoblastic transdifferentiation and reduces Notch1 and Twist1 expression, making MEIS2 a potential target for CAVD prevention. Section title: Discussion Educational score: 4.490106582641602 Domain: biomedical Document type: Study Language: en A recent study reexamined ISL1’s role in human embryonic stem cell-based cardiac development, revealing that ISL1 accelerates cardiomyocyte differentiation rather than stabilizing precursor cells . Depletion of ISL1 delays cardiac differentiation and alters cardiomyocyte identity, as ISL1 interacts with retinoic acid signaling and MEIS2, competing with the retinoic acid pathway and the atrial specifier NR2F1 for cardiomyocyte fate. These findings provide valuable insights for cardiac regeneration strategies. Although the neonatal heart has inherent regenerative potential through cardiomyocyte proliferation, this capacity diminishes after postnatal day 7. We previously demonstrated that deleting MEIS1 in mouse cardiomyocytes extends the postnatal proliferative period and reactivates cardiomyocyte mitotic activity in adult hearts. MEIS1 plays a crucial role in activating critical CDK inhibitors, such as p15, p16, and p21, marking it as a fundamental regulator of cardiomyocyte proliferation and a promising therapeutic target for heart regeneration . Our observations with mouse heart tissue further support the potential of MEIS1 inhibitors to stimulate ventricular cardiomyocyte proliferation, downregulate CDKIs, and enhance cardiovascular regeneration, highlighting their prospective role in developing regenerative treatment strategies. Section title: Discussion Educational score: 4.204897880554199 Domain: biomedical Document type: Study Language: en A recent study investigated the role of Meis1 in ischemic arrhythmias in mice . Meis1 overexpression was found to reduce ventricular arrhythmias and improve cardiac conduction velocity, partly by restoring the function of cardiac Na + channels. Additionally, the study revealed that E3 ubiquitin ligase CDC20 plays a role in this process, highlighting a new mechanism for Na V 1.5 channel dysregulation in infarcted hearts. Fascinatingly, through the utilization of a Cre-dependent CasRx knock-in mouse model enabling precise gene suppression, another research team effectively downregulated Meis1 and Hoxb13 expression in ventricular cardiomyocytes . This intervention spurred cardiac regeneration after a myocardial infarction while also inhibiting the lncRNA Mhrt. Section title: Discussion Educational score: 4.089958190917969 Domain: biomedical Document type: Review Language: en MEIS proteins have a well-established connection with cancer, being implicated in tumorigenesis, metastasis, and invasion. In different cellular contexts, they can act as either tumor suppressors or oncogenes, and their expression frequently becomes dysregulated in various cancers . Studies have indicated their upregulation in cancers such as leukemia, lymphoma, thymoma, pancreas, glioma, and glioblastoma, as well as downregulation in cervical, uterine, rectal, and colon cancers. It is noteworthy that, within each cancer type, at least one subtype exhibits elevated MEIS expression. Furthermore, research has identified the potential of MEIS proteins and their associated factors as diagnostic or therapeutic biomarkers for various diseases. Section title: Discussion Educational score: 4.128876686096191 Domain: biomedical Document type: Study Language: en There is a historical association between Meis1 and acute leukemia, a challenging hematological disease characterized by resistance to therapy and frequent relapses. Meis1 has been implicated in the pathogenesis of various cancers, with historical observations linking its overexpression to both acute lymphoblastic leukemia and acute myeloid leukemia . Elevated MEIS1 expression in leukemic blast samples is associated with resistance to conventional treatments. A recent study indicated that MEIS inhibitors have the potential to reduce the viability of leukemia stem cells by inducing apoptosis, suggesting their possible use in limiting leukemia relapse and overcoming chemotherapeutic resistance . These findings imply that MEIS inhibitors could be promising for the treatment of leukemia and potentially other disorders characterized by similar resistance mechanisms. Section title: Discussion Educational score: 4.04145622253418 Domain: biomedical Document type: Study Language: en In addition, we have recently shown that newly developed MEIS inhibitors selectively hinder the growth of prostate cancer cells with high MEIS expression, triggering apoptosis . MEIS inhibition effectively reduced the viability of various prostate cancer cell lines and increased apoptosis, particularly in cells with elevated MEIS levels. These findings suggested the potential use of MEIS inhibitors for targeting high MEIS-expressing prostate cancer, although further research is needed before clinical application. The observations in leukemia and solid cancer cases indicate the potential utility of MEIS inhibitors in the management of MEIS-dependent or MEIS-positive malignancies. Section title: Discussion Educational score: 4.506263732910156 Domain: biomedical Document type: Study Language: en It is intriguing that our findings reveal differential effects of MEIS inhibition on cardiac fibroblasts compared to cardiomyocytes. To understand why MEIS1 impacts the cell cycle of these cell types differently, it is crucial to recognize that the precise mechanisms by which MEIS1 and its cofactors regulate cardiomyocytes versus fibroblasts are not yet fully elucidated. MEIS1 plays a role in regulating gene expression programs specific to each cell type, but the exact mechanisms by which MEIS1 and its cofactors differentially influence cardiac fibroblasts and cardiomyocytes remain unclear. In fibroblasts, MEIS1 is part of a regulatory network that maintains fibroblast-specific gene expression and suppresses cardiomyocyte-specific genes . This function is crucial for preserving fibroblast identity and function. However, the impact of MEIS1 on the cell cycle and gene expression in cardiomyocytes is less well defined and may involve interactions with other transcription factors and regulatory elements that are unique to cardiomyocytes. Our current understanding is limited regarding how MEIS1 and its cofactors are expressed and function differently in cardiac fibroblasts versus cardiomyocytes. This gap in knowledge suggests that MEIS1’s role in these cell types could be more complex than previously thought, potentially involving distinct regulatory networks and mechanisms that influence cell cycle dynamics and differentiation. Further research is needed to elucidate these differences and understand how MEIS1’s actions in these cell types contribute to their unique behaviors and responses. Section title: Discussion Educational score: 4.524152755737305 Domain: biomedical Document type: Review Language: en Heart failure, a widespread medical condition marked by reduced cardiac contractility and limited cardiomyocyte regeneration, underscores the need for innovative strategies in cardiac regeneration. While the mammalian heart exhibits regenerative potential in neonatal stages, this capacity diminishes after postnatal day 7. Studies have identified Meis1 as a crucial regulator of the cardiomyocyte cell cycle, offering promise in enhancing cardiac regeneration. The use of MEIS1 inhibitors, which promote cardiomyocyte proliferation and gene modulation, may serve as a potential therapeutic approach to stimulate cardiac repair. In addition to their relevance in cardiac regeneration, MEIS inhibitors hold promise in the context of cancer. MEIS proteins are associated with tumorigenesis and research indicates that MEIS inhibitors have the potential to reduce the viability of leukemia stem cells and induce apoptosis, suggesting their utility in addressing chemotherapeutic resistance in leukemia. Moreover, newly developed MEIS inhibitors exhibit efficacy in selectively blocking prostate cancer cells with high MEIS expression, triggering apoptosis. These findings highlight the multifaceted potential of MEIS inhibitors in addressing cardiomyocyte regeneration and managing MEIS-dependent or MEIS-positive malignancies. | Review | biomedical | en | 0.999997 |
PMC11698223 | Section title: Introduction Educational score: 3.9894707202911377 Domain: biomedical Document type: Review Language: en Total hip arthroplasty (THA) is a highly common and successful procedure in the US with over 460,000 surgeries performed annually and expected to grow significantly by 2030 . Complication rates remain low with the most common reasons for failure being dislocation, fracture, and infection . With improvements in implant technology, failure rates from component failure have continued to improve over time. Improved polyethylene annealing and sterilization in inert gasses have led to improved wear characteristics and decreased component failure rates . Bearing surfaces have continued to evolve over the years, decreasing the component failure rates. Section title: Introduction Educational score: 4.166957378387451 Domain: biomedical Document type: Review Language: en The most common types of bearing surfaces applied in THA are metal-on-metal (MoM), metal-on-polyethylene (MoP), ceramic-on-ceramic (CoC), and ceramic-on-polyethylene (CoP). The most common bearing surfaces used in the US are MoP and CoP. MoP has shown higher wear rates in studies and is still susceptible to problems with trunnionosis, especially in large head sizes . First-generation ceramic heads were made from alumina, and due to their brittle nature had issues with ceramic head fracture rates of 13.4% . Zirconia and other metals have been added to ceramic components for their many benefits: increased hardness, scratch resistance, and lack of debris production . One major drawback to the use of CoC bearings is the ceramic commonly breaks without plastic deformation due to its high elastic modulus . Production processes have become more advanced, including the addition of zirconia to the BIOLOX delta heads, leading to increased durability and decreased fracture rates . Methods and tools used to implant the prosthesis have also changed slightly over time, leading to increased survivability rates and decreased revision rates . Despite the advancements in implant technology, ceramic head fractures still occur, although typically in CoC-bearing surfaces. Section title: Introduction Educational score: 3.1516735553741455 Domain: clinical Document type: Clinical case Language: en Herein we present a case of atraumatic ceramic head fracture from right THA in a CoP patient. To our knowledge, this is the first atraumatic case presented in the literature of a newer-generation ceramic head fracture with a polyethylene-bearing surface. Section title: Case presentation Educational score: 3.419325828552246 Domain: clinical Document type: Clinical case Language: en The patient is a 73-year-old female who underwent an uncomplicated, anterior approach cemented right total hip arthroplasty. Intraoperatively there was no trauma and we had good exposure of the femur and trunnion. Before implantation of the femoral head, the trunnion was cleaned in a typical fashion. We implanted a 36+0 standard femoral head and the hip was stable through all ranges of motion. She was doing well and was ambulating with physical therapy without pain or complication. Early on while working with PT, she felt a clunk and noticed some shortening of the leg. Radiographs were taken and showed a fracture of the femoral head . She still had minimal pain, and there was no fall or trauma. She was subsequently taken back and revised with the femoral head and liner. The liner was destroyed by the trunnion buried into the polyethylene liner. We slowly removed all of the fragments from the ceramic head and pieced them back together to ensure all pieces were removed . We also confirmed this with intraoperative fluoroscopy. Once this was done we removed the polyethylene liner and replaced this component with a new one. We replaced the head with a new 36+3 femoral head. During dissection to remove all of the ceramic debris further soft tissue release was required necessitating an increase in neck length for stability. The patient did well with physical therapy and was subsequently discharged to home. We followed her for three months postoperatively with no further complications and full range of motion without pain. The rest of her postoperative course was uneventful. The components were packaged and sent back to the manufacturer for analysis. The patient has a two-year follow-up with no pain and no complications. Informed consent was obtained from the patient for the publication of this case report and its images. Section title: Discussion Educational score: 4.103751182556152 Domain: biomedical Document type: Clinical case Language: en Ceramic head fracture following THA is a rare, but catastrophic complication. Rates have decreased following the switch from alumina to BIOLOX delta ceramic heads . Our case represents the only case of an atraumatic fracture of a BIOLOX delta ceramic on a polyethylene hip in the literature. One major category of ceramic materials used in hip arthroplasty is alumina (Al 2 O 3 ). Pure alumina heads are associated with a relatively high incidence of clinical fracture of 0.0201% when compared to the 0.0010% found with alumina matrix composite . Although both material’s fracture rates are extremely low, the reliability is even better with alumina matrix heads. Squeaking is a commonly associated problem with hard-on-hard bearing hip replacements and can be caused by improper fluid film lubrication in the bearing. Causes of this include stripe wear, edge loading, introduction of unwanted particles, and ceramic fracture . The rubbing of non-lubricated parts may produce sounds audible to humans, however, this complication has not been directly associated with pain. Section title: Discussion Educational score: 4.034693717956543 Domain: biomedical Document type: Study Language: en Stripe wear has also been found to play a role in the durability of ceramic bearings. Stripe wear is caused by a microseparation of the femoral head leading to impingement during different parts of the gait cycle. It has also been found that stripe wear may occur due to a lack of lubrication during edge loading . As stripe wear begins to form, it becomes more likely for the problem to progress faster with time. The wettability of the surface has been found to have an impact on the durability of prosthetic materials. Materials with high wettability allow a fluid to remain in contact with a surface. Ceramic materials are often harder and smoother than their metal alloy counterparts, allowing for better lubrication . High wettability is associated with the promotion of material-tissue interaction, but may also be associated with increased corrosion, therefore a material with well-balanced wettability characteristics must be used . Section title: Discussion Educational score: 3.3142354488372803 Domain: biomedical Document type: Other Language: en Although ceramic’s hardness is what makes it so good for use as a material in prosthetics, it is also one of its largest downfalls due to the likelihood of fracture with little plastic deformation due to its high elastic modulus . Increased material hardness is desired when making a prosthetic, especially for younger patients, due to its linkage to better corrosion resistance and overall toughness . Due to ceramic’s naturally high modulus of elasticity, it is naturally poor at dampening impacts made to the material and can lead to lubrication and durability issues in the future. Section title: Discussion Educational score: 4.175937652587891 Domain: biomedical Document type: Review Language: en BIOLOX delta ceramic heads were first introduced in 2003 and the delta-delta hip bearing was introduced in 2010. The ceramics used were combined with zirconia and several other materials to improve material hardness and further decrease the possibility of crack formation . This new ceramic was also produced as an attempt to minimize the production of minute commutia following a fracture by increasing bend strength . Recent registry data reveals a fracture risk for BIOLOX delta of 0.1% . This rate may be even lower for ceramic-on-polyethylene bearings, considering the data used was solely based on ceramic-on-ceramic bearings . With the low fracture rate of fourth-generation ceramic-on-ceramic bearings, other components are being analyzed for their contribution to revision rates. Ceramic surfaces also minimize or even negate the risk of trunnionosis, which has been found to account for up to 3% of all revisions . Wear patterns associated with ceramic-on-ceramic bearings have even been found to have improved performance during stop-dwell-start motions when compared to ceramic-on-polyethylene and metal-on-polyethylene bearings . Section title: Discussion Educational score: 3.377548933029175 Domain: biomedical Document type: Clinical case Language: en The literature contains many examples of traumatic ceramic head fractures in THA but does not contain many non-traumatic examples. This case is even more rare since the fracture occurred days following the procedure. In discussion with the company post-implant analysis, it was determined that this was likely a machining defect. There was either a slight defect in the ceramic head or a slight mismatch in the Morse taper leading to catastrophic failure. Another option would be a slight defect in the femoral stem taper but we had no further issues with the new ceramic head so that was excluded. It is also possible that the head was placed malaligned during impaction but there were no complications during surgery and we had a good fit intraoperatively. No other common causes of non-traumatic head fracture seem to be validated due to the paucity of these cases in the literature. Section title: Conclusions Educational score: 4.128005027770996 Domain: clinical Document type: Clinical case Language: en This case study highlights a rare instance of atraumatic ceramic head fracture in a CoP-bearing surface following THA. Despite advancements in ceramic technology, including the development of BIOLOX delta heads that are engineered for increased fracture resistance, this case demonstrates that ceramic fractures remain a possible complication. Although the fracture may have resulted from a machining defect or mismatch at the trunnion interface, the underlying cause remains speculative due to the low incidence of atraumatic ceramic fractures in THA. This case underscores the importance of ongoing advancements in implant manufacturing processes and material quality control to further reduce these rare complications. Overall, while THA continues to demonstrate excellent outcomes with low complication rates, this case emphasizes that vigilance and refinement in implant technology remain critical for optimizing patient outcomes. | Review | biomedical | en | 0.999997 |
PMC11698264 | Section title: Introduction Educational score: 1.6180777549743652 Domain: other Document type: Other Language: en Psychological well-being (PWB) is a multidimensional construct that encompasses various aspects of positive functioning, including self-acceptance, personal growth, purpose in life, environmental mastery, autonomy, and positive relationships with others. In recent years, there has been growing interest in understanding how different life roles and occupational status influence women's PWB, particularly in the context of evolving societal norms and expectations . Section title: Introduction Educational score: 1.286045789718628 Domain: other Document type: Other Language: en The comparison between housewives and working women's PWB has emerged as a significant area of research, especially in developing nations like India where traditional and modern roles often intersect . Working women often navigate multiple roles, balancing professional responsibilities with domestic duties, which can impact their PWB in complex ways . Studies have shown that employment can provide women with financial independence, social connections, and a sense of achievement, potentially enhancing their PWB . However, the relationship between employment status and PWB is not straightforward, as working women may experience additional stressors related to role conflicts and work-life balance . Section title: Introduction Educational score: 2.013676166534424 Domain: biomedical Document type: Study Language: en Conversely, housewives, who focus primarily on domestic responsibilities, may experience different challenges affecting their PWB . Recent research has highlighted that both groups face unique stressors that can influence their mental health and overall life satisfaction . A study conducted in North Bihar, India, found significant differences in PWB between housewives and working women, suggesting that occupational status may play a crucial role in determining mental health outcomes . Section title: Introduction Educational score: 2.470041036605835 Domain: biomedical Document type: Study Language: en The COVID-19 pandemic has further complicated this dynamic, with studies indicating varying impacts on women's PWB based on their occupational status . The lockdown periods particularly affected women's mental health, regardless of their working status, highlighting the need for continued research in this area . Additionally, recent studies have emphasized the strong connection between PWB and physical health outcomes, suggesting that understanding these differences has important implications for overall health . Section title: Introduction Educational score: 1.9133834838867188 Domain: other Document type: Study Language: en The measurement of PWB has evolved significantly since Ryff's pioneering work, which established the theoretical framework for understanding its multiple dimensions . This multidimensional approach has become increasingly important in assessing the complex nature of well-being among different populations . Recent studies in various parts of India have employed this framework to examine PWB among women, considering factors such as marital status, employment, and socioeconomic conditions . Section title: Introduction Educational score: 2.085442066192627 Domain: other Document type: Study Language: en Recent studies have also highlighted the importance of socioeconomic factors and regional variations in determining PWB among women . The economic development and social changes in Tamil Nadu have created unique opportunities and challenges for both working women and housewives . While some research has explored general well-being patterns, there is limited understanding of how specific domains of PWB might differ between these groups in semi-urban areas like Perambalur district . Furthermore, the use of standardized assessment tools, particularly the Ryff's PWB Scale (PWBS), has proven valuable in capturing these nuanced differences across various populations . Understanding these domain-specific variations could be crucial for developing targeted interventions and support systems for women in different occupational roles . Section title: Introduction Educational score: 2.3557627201080322 Domain: other Document type: Study Language: en Despite the growing body of research in this area, there remains a need for region-specific studies that can account for local cultural and social contexts . Tamil Nadu in India, with its unique social and cultural landscape, presents an important setting for examining these differences. Furthermore, while several studies have explored overall PWB, fewer have focused on domain-specific differences between homemakers and employed women . Hence, this study aimed to compare the PWB among homemakers and employed women in Perambalur district, Tamil Nadu, India, by assessing both overall and domain-specific scores using the 18-item Ryff's PWBS (PWBS-18). Section title: Materials and methods Educational score: 3.0022799968719482 Domain: biomedical Document type: Study Language: en This was a community-based cross-sectional study, conducted in the field practice area of Dhanalakshmi Srinivasan Medical College and Hospital (DSMCH), a tertiary care teaching hospital in the Perambalur district of Tamil Nadu, India, between March 2023 and February 2024. The study protocol was approved by the Institutional Ethics Committee of DSMCH (approval number: IECHS/IRCHS/No. 392). Written informed consent was obtained from all participants after explaining the study objectives and procedures in their preferred language. Participant confidentiality was maintained throughout the study, and data were stored securely following standard research protocols. Section title: Materials and methods Educational score: 2.023653268814087 Domain: biomedical Document type: Study Language: en Inclusion and exclusion criteria Section title: Materials and methods Educational score: 2.277235984802246 Domain: biomedical Document type: Study Language: en The study included married women aged 18 years and above who were either homemakers or employed in any occupation. Employed women were defined as individuals who engaged in paid employment outside the home, whether in the formal or informal sectors, and met the specific criteria: (a) They must receive regular monetary compensation; (b) They must work at least 20 hours per week in economic activities outside the home. Homemakers included women who failed to meet these criteria. Women with diagnosed severe psychiatric illnesses, those unable to comprehend the questionnaire, and those unwilling to participate were excluded from the study. Section title: Materials and methods Educational score: 1.761410117149353 Domain: biomedical Document type: Study Language: en Sample size estimation and sampling method Section title: Materials and methods Educational score: 3.839193105697632 Domain: biomedical Document type: Study Language: en The sample size was calculated based on a previous study by Choudhary and Ahmed in India, which reported that 55% of working women demonstrated high levels of perceived PWB . The minimum required samples in the study were calculated using Cochran's formula for calculating sample size: n = Z 2 × p × (1-p) / d 2 , where p = 0.55 (prevalence) and d = 0.05 (5% absolute precision) at 95% confidence level (Z 2 =3.84). The calculation yielded a minimum required sample size of 380 participants. The study population comprised adult women aged 18 years and above from both urban and rural areas within the field practice area of DSMCH. Participants were recruited using convenience sampling methodology. Section title: Materials and methods Educational score: 1.5420197248458862 Domain: biomedical Document type: Other Language: en Data collection procedure Section title: Materials and methods Educational score: 2.6453981399536133 Domain: biomedical Document type: Study Language: en An interviewer conducted face-to-face interviews with participants using a semi-structured questionnaire. The questionnaire included two main sections. The first section included sociodemographic information such as age, marital status, education, family type, residence, socioeconomic status, family size, spouse addiction status, occurrence of vital events, presence of chronic illness, and debt status. Socioeconomic status was classified based on the Modified BG Prasad classification . The second section includes the Ryff's PWBS-18. The interviews were conducted in the local language, with appropriate translation and back-translation procedures followed to ensure content validity. Each interview lasted approximately 30-45 minutes, and privacy was maintained throughout the data collection process. Section title: Materials and methods Educational score: 1.4197207689285278 Domain: biomedical Document type: Study Language: en Study tool Section title: Materials and methods Educational score: 2.7902934551239014 Domain: biomedical Document type: Study Language: en PWB was assessed using Ryff's PWBS-18 . This scale measures six dimensions of PWB: autonomy, environmental mastery, personal growth, positive relations with others, purpose in life, and self-acceptance . Each subscale item is evaluated on a six-point Likert scale, with 1 representing "strongly disagree" and 6 indicating "strongly agree." The components for the Autonomy subscale are Q15, Q17, and Q18. The items on the Environmental Mastery subscale are Q4, Q8, and Q9. The items for the Personal Growth subscale are Q11, Q12, and Q14. The items for the Positive Relations with Others subscale are Q6, Q13, and Q16. The items for the Purpose in Life subscale are Q3, Q7, and Q10. The items for the Self-Acceptance subscale are Q1, Q2, and Q5. Section title: Materials and methods Educational score: 1.9743551015853882 Domain: biomedical Document type: Other Language: en Questions 1, 2, 3, 8, 9, 11, 12, 13, 17, and 18 need reverse scoring. Reverse-scored items are phrased contrary to the intended measurement of the scale. To compute subscale scores for each participant, aggregate the respondents' responses to the items of each subscale. Elevated scores indicate enhanced PWB across each category. Section title: Materials and methods Educational score: 3.516298532485962 Domain: biomedical Document type: Study Language: en Table 1 shows the internal consistency reliability of the PWBS-18 was assessed using Cronbach's alpha (α = 0.682, standardized α = 0.709). While this reliability coefficient is slightly below the conventional threshold of 0.70, it is considered acceptable for a short-form version of an established scale . Therefore, all items were retained for analysis to maintain the scale's validated structure and enable comparability with existing literature. Section title: Materials and methods Educational score: 0.9184456467628479 Domain: biomedical Document type: Other Language: tl Data analysis Section title: Materials and methods Educational score: 3.9822096824645996 Domain: biomedical Document type: Study Language: en The data analysis was performed using IBM SPSS Statistics for Windows, Version 26.0 . The descriptive statistics for the sociodemographic variables were presented as frequency and percentage for categorical variables, and for continuous variables it was presented as mean and SD. The overall PWB scores and individual domain scores were presented as mean, standard deviation, median, and IQR for both homemakers and employed women. To compare the overall PWB scores between homemakers and employed women, an independent t-test was conducted. To compare the domain-specific PWB scores between homemakers and employed women, the Mann-Whitney U Test was conducted. For comparing the six domains of PWB between the groups, a one-way multivariate analysis of variance (MANOVA) was performed. The assumptions of MANOVA, including multivariate normality and homogeneity of variance-covariance matrices, were checked using Box's M test. MANOVA showed significant differences (p < 0.05), and subsequent post-hoc analyses using Bonferroni correction were conducted to identify which specific domains differ between the groups. Section title: Results Educational score: 1.784381628036499 Domain: biomedical Document type: Study Language: en Among the total participants (n= 308), 172 (55.8%) were homemakers, while 136 (44.2%) were employed women. Figure 1 illustrates the distribution of participants by their occupational status, showing a relatively balanced representation of both groups in the study population, with a slightly higher proportion of homemakers compared to employed women. Section title: Results Educational score: 3.6790475845336914 Domain: biomedical Document type: Study Language: en Table 2 shows the sociodemographic characteristics of study participants based on occupational status. The mean age of homemakers (44.7 ± 14.06 years) was higher than employed women (37.12 ± 9.96 years). Among married women, 143 (56.7%) were homemakers and 109 (43.3%) were employed women. For education status, most illiterate women were homemakers (n=21, 77.8%), while the majority of graduates were employed (n=84, 75%). In terms of family type, joint families had more homemakers (n=88, 71.5%), while nuclear families showed a more balanced distribution with 84 (46.2%) homemakers and 98 (53.8%) employed women. Rural residence was more common among homemakers (n=146, 72.3%), while urban residence was predominant among employed women (n=80, 75.5%). Regarding socioeconomic status, higher classes (Class 1 and 2) had more employed women (n=31, 73.8% and n=49, 69%, respectively), while lower classes (Class 4 and 5) had more homemakers (n=75, 78.1% and n=25, 92.6%, respectively). Family size distribution showed that medium-sized families (four to six members) were most common in both groups, with 104 (52.5%) homemakers and 94 (47.5%) employed women. Additional characteristics showed an equal distribution of spouse addiction between groups (n=36, 50% each). Vital events occurred in 21 (43.8%) homemakers and 27 (56.3%) employed women. Chronic illness was present in 33 (54.1%) homemakers and 28 (45.9%) employed women, while debts were reported by 82 (59%) homemakers and 57 (41%) employed women. Section title: Results Educational score: 3.5052402019500732 Domain: biomedical Document type: Study Language: en Table 3 shows the comparison of overall and domain-specific PWB scores between homemakers and employed women. The overall PWB score was slightly higher among homemakers (mean: 69.35 ± 6.595) compared to employed women (mean: 68.21 ± 6.046). Among the six domains, autonomy scores were higher in employed women (mean: 13.44 ± 2.121; median: 14) compared to homemakers (mean: 12.88 ± 2.716; median: 14). Environmental mastery showed higher scores in homemakers (mean: 9.53 ± 3.879; median: 9) than employed women (mean: 8.88 ± 3.703; median: 9). Personal growth and positive relations with other domains showed slightly higher scores among homemakers (mean: 11.05 ± 2.423 and 12.2 ± 3.051, respectively) compared to employed women (mean: 10.65 ± 3.042 and 11.99 ± 3.607, respectively). Purpose in life was similar between groups, with employed women showing a marginally higher score (mean: 13.4 ± 2.715; median: 14) compared to homemakers (mean: 13.24 ± 2.207; median: 13.5). Self-acceptance was higher among homemakers (mean: 10.44 ± 1.488; median: 10) compared to employed women (mean: 9.86 ± 1.005; median: 10). Section title: Results Educational score: 3.1496617794036865 Domain: biomedical Document type: Study Language: en Table 4 shows the comparison of overall PWB scores between homemakers and employed women. Homemakers demonstrated a marginally higher mean score (69.35 ± 6.60) compared to employed women (68.21 ± 6.05). Levene's test confirmed the homogeneity of variances (F = 1.410, p = 0.236). The independent t-test revealed no statistically significant difference in overall PWB scores between the groups (p = 0.121). Section title: Results Educational score: 3.7131831645965576 Domain: biomedical Document type: Study Language: en Figure 2 shows the comparison of the distribution of PWB domain scores between homemakers (n = 172, shown in blue) and employed women (n = 136, shown in red) using a Mann-Whitney U test. The autonomy domain demonstrated similar median scores between groups, though homemakers showed greater score variability. Environmental mastery exhibited a broader distribution pattern across both groups, indicating diverse levels of mastery over their environments. Personal growth scores revealed comparable patterns between the groups, with subtle differences in their distributions. The positive relations with other domains showed similar central tendencies between homemakers and employed women, suggesting comparable social relationship qualities. Purpose in life scores display relatively symmetrical distributions for both groups, indicating similar levels of life purpose perception. Finally, the self-acceptance domain showed more concentrated scores among employed women compared to a wider distribution among homemakers, suggesting more varied levels of self-acceptance in the latter group. The mean rank values are displayed for each group across all domains, providing quantitative measures of central tendency. Section title: Results Educational score: 2.415348529815674 Domain: biomedical Document type: Study Language: en A Mann-Whitney U test was conducted to examine differences in PWB dimensions between employed women and homemakers (n = 308). The analysis revealed that five of the six dimensions showed no statistically significant differences between the two groups (Table 5 ). However, a significant difference was found in self-acceptance scores between employed women and homemakers , indicating that employment status may influence individuals' level of self-acceptance. Section title: Results Educational score: 4.006818771362305 Domain: biomedical Document type: Study Language: en Table 6 presents the results of MANOVA comparing six domains of PWB between homemakers and employed women. Prior to the main analysis, Box's M test was conducted to examine the assumption of homogeneity of variance-covariance matrices. Box's M test indicated that the assumption of homogeneity of variance-covariance matrices was violated (M = 69.174, F = 3.22, p < 0.001). Given the relatively large and balanced sample sizes, we proceeded with MANOVA using Pillai's Trace as the test statistic due to its robustness to assumption violations. MANOVA revealed a significant multivariate effect of employment status on PWB domains (Pillai's Trace = 0.071, F (6, 301) = 3.827, p = 0.001, partial η² = 0.071). This result indicates that there are significant differences in PWB profiles between employed women and homemakers, though the effect size suggests these differences are modest in magnitude. Section title: Results Educational score: 3.5047614574432373 Domain: other Document type: Study Language: en Subsequent univariate analyses were conducted to examine differences between homemakers and employed women across six domains of PWB. The results revealed significant differences in two domains: self-acceptance and autonomy. Self-acceptance demonstrated the most robust difference between groups (p = 0.001, partial η² = 0.048), with homemakers reporting higher levels compared to employed women. The effect size indicates that group membership accounted for 4.8% of the variance in self-acceptance scores. Autonomy showed a marginally significant difference (p = 0.050, partial η² = 0.012), with employed women scoring higher than homemakers. The remaining four domains did not exhibit statistically significant differences between groups. The effect sizes for these non-significant domains were notably small, ranging from 0.001 to 0.007, suggesting minimal practical differences between the groups in these aspects of PWB. Section title: Discussion Educational score: 2.122373342514038 Domain: other Document type: Study Language: en The present study provides valuable insights into the PWB of homemakers and employed women in the Perambalur district, Tamil Nadu, revealing complex patterns in both overall well-being and specific psychological domains. The findings contribute to our understanding of how occupational status influences women's mental health in the Indian sociocultural context. Section title: Discussion Educational score: 3.553863763809204 Domain: biomedical Document type: Study Language: en Our analysis revealed that homemakers demonstrated slightly higher overall PWB scores (69.35 ± 6.595) compared to employed women (68.21 ± 6.046), though this difference was not statistically significant (p = 0.121). This finding aligns with research by Choudhary and Ahmad, who reported similar patterns in their study of women in North Bihar . The lack of significant differences in overall scores suggests that employment status alone may not be the primary determinant of women's PWB, supporting Sinha's assertion that multiple roles and their successful management are more crucial for psychological health than employment status per se . Section title: Discussion Educational score: 3.7500624656677246 Domain: biomedical Document type: Study Language: en The multivariate analysis revealed significant differences in PWB profiles between the groups (Pillai's Trace = 0.071, p = 0.001), particularly in the self-acceptance and autonomy domains. The higher self-acceptance scores among homemakers (p = 0.001, partial η² = 0.048) suggest that these women may have developed a stronger sense of identity and satisfaction within their chosen role. This finding resonates with research by Chaudhry and Chhajer, who emphasized the importance of role satisfaction in PWB . Section title: Discussion Educational score: 2.3966727256774902 Domain: biomedical Document type: Study Language: en Employed women demonstrated marginally higher autonomy scores (p = 0.050, partial η² = 0.012), consistent with findings by De-Juanas et al. regarding the relationship between autonomy and PWB . This increased autonomy might be attributed to financial independence and workplace empowerment, as suggested by Houston et al. in their comparative study of employed women and homemakers . Section title: Discussion Educational score: 2.380236864089966 Domain: biomedical Document type: Study Language: en The sociodemographic analysis revealed important patterns that may influence PWB. The higher prevalence of homemakers in rural areas (146,72.3%) and employed women in urban areas (80, 75.5%) reflects broader sociocultural and economic factors affecting women's employment choices. This geographic distribution pattern aligns with findings by Maeda et al., who identified significant associations between domestic work stress and psychological health outcomes across different residential settings . Section title: Discussion Educational score: 1.468489646911621 Domain: other Document type: Study Language: en The concentration of employed women in higher socioeconomic classes (n = 31, 73.8% in Class 1 and n = 49, 69% in Class 2) suggests that economic status and educational attainment significantly influence women's occupational choices. This observation supports research by Bramhankar et al., who found strong correlations between socioeconomic status and life satisfaction among Indian adults . Section title: Discussion Educational score: 1.337931513786316 Domain: other Document type: Study Language: en The absence of significant differences in environmental mastery, personal growth, positive relations, and purpose in life between groups is particularly noteworthy. This finding suggests that both homemakers and employed women can achieve similar levels of fulfillment in these domains through different pathways, supporting Ryff and Keyes' conceptualization of PWB as a multidimensional construct . Section title: Discussion Educational score: 1.8016293048858643 Domain: biomedical Document type: Study Language: en Recent research by Beulah suggests that the relationship between employment status and PWB is mediated by various factors, including social support, family dynamics, and personal aspirations . This may explain why both groups showed comparable scores in several domains despite different daily experiences and challenges. Section title: Discussion Educational score: 1.3946187496185303 Domain: other Document type: Study Language: en The similar scores in positive relations across both groups indicate that women can develop and maintain meaningful social connections regardless of their occupational status. This finding aligns with research by Arcos-Romero and Calvillo, who emphasized the importance of social relationships in women's overall well-being, regardless of their professional status . Section title: Discussion Educational score: 1.60987389087677 Domain: other Document type: Study Language: en The marginally higher environmental mastery scores among homemakers (mean: 9.53 ± 3.879) compared to employed women (mean: 8.88 ± 3.703) suggest that managing household responsibilities may enhance women's sense of control over their immediate environment. This finding corresponds with research by Parmar, who found that homemakers often develop strong organizational and management skills through their domestic responsibilities . Section title: Discussion Educational score: 1.1249622106552124 Domain: other Document type: Other Language: en The slightly higher personal growth scores among homemakers challenge the common assumption that professional employment is necessary for personal development. This finding supports research by Chaurasia and Kumari, who found that both employed and non-employed women can experience significant personal growth through different life experiences and responsibilities . Section title: Discussion Educational score: 1.950269341468811 Domain: biomedical Document type: Study Language: en The socioeconomic distribution pattern in our study, with employed women predominantly in higher classes, raises important questions about access to employment opportunities and its relationship with PWB. This observation aligns with findings by Dhanabhakyam and Sarath, who identified socioeconomic status as a significant moderator of PWB among women . Section title: Discussion Educational score: 3.458219289779663 Domain: biomedical Document type: Study Language: en The findings of this study have significant implications for developing targeted mental health interventions and support systems for women across different occupational statuses. The identification of distinct PWB profiles between homemakers and employed women suggests the need for tailored mental health promotion strategies . For instance, the higher autonomy scores among employed women indicate that workplace mental health programs should focus on maintaining and enhancing this strength while addressing potential challenges in self-acceptance. Conversely, community-based mental health initiatives for homemakers could focus on enhancing autonomy while building upon their stronger self-acceptance . Section title: Discussion Educational score: 4.048487186431885 Domain: biomedical Document type: Study Language: en The socioeconomic disparities observed in our study, particularly the concentration of employed women in higher socioeconomic classes, highlight the need for public health policies that address barriers to employment and mental health support for women in lower socioeconomic groups . Additionally, the similar scores in positive relations and purpose in life across both groups suggest that community-based support networks and social engagement programs could be equally effective for both homemakers and employed women, potentially serving as a cost-effective public health intervention strategy. Healthcare providers and public health practitioners should consider these findings when designing preventive mental health services and wellness programs, ensuring that interventions are culturally sensitive and address the specific psychological needs of both homemakers and employed women in different socioeconomic contexts . Section title: Discussion Educational score: 2.058208703994751 Domain: biomedical Document type: Other Language: en Strengths of the study Section title: Discussion Educational score: 4.120613098144531 Domain: biomedical Document type: Study Language: en The study demonstrated several notable strengths in its approach and execution. The research utilized the validated Ryff's PWBS-18, providing a comprehensive assessment of both overall and domain-specific well-being. The methodology was strengthened by relatively balanced sample sizes between groups and the application of appropriate statistical analyses, including MANOVA and Mann-Whitney U tests. The study's robustness was further enhanced by using Pillai's Trace to address violated assumptions in statistical analysis. Additionally, the research incorporated a detailed examination of socio-demographic variables, including various family-related factors such as family type, size, and spouse addiction, as well as health and financial considerations like chronic illness and debts. This comprehensive approach provided a rich context for understanding the relationship between occupational status and PWB. Section title: Discussion Educational score: 1.559439778327942 Domain: biomedical Document type: Other Language: it Limitations Section title: Discussion Educational score: 3.954470634460449 Domain: biomedical Document type: Study Language: en Several limitations should be considered when interpreting the study's findings. The cross-sectional design inherently limits causal inference, and the focus on a single geographic location (Perambalur district) may affect the generalizability of results to other populations. The study's measurement approach faced some challenges, including relatively low internal consistency (Cronbach's α = 0.682) and the use of a shortened version of the PWBS, which might not capture the full complexity of the PWB construct. There were also analytical limitations, such as the violation of the homogeneity assumption in MANOVA and limited control for potential confounding variables. The absence of analysis regarding interaction effects between demographic variables represents another limitation of the study's scope. Section title: Conclusions Educational score: 3.7175614833831787 Domain: biomedical Document type: Study Language: en This study provides valuable insights into the complex relationship between women's occupational status and PWB in the Perambalur district of Tamil Nadu. While the overall PWB scores were comparable between both groups, the study revealed significant domain-specific differences. Homemakers demonstrated higher self-acceptance, suggesting a more stable self-concept and greater acceptance of their life choices, while employed women showed higher autonomy, reflecting increased independence and decision-making opportunities. The absence of significant differences in environmental mastery, personal growth, positive relations, and purpose in life domains indicates that both groups find distinct ways to fulfill these aspects of PWB. These findings challenge common assumptions about the relative advantages of employment versus staying at home and suggest that PWB is more nuanced than previously understood, influenced by factors such as family support, personal choice, and social circumstances. Section title: Conclusions Educational score: 3.193157911300659 Domain: biomedical Document type: Other Language: en Future research should prioritize longitudinal studies across diverse geographical and socioeconomic contexts to better understand the temporal dynamics of PWB among women. Healthcare providers and policymakers should develop targeted mental health interventions addressing the specific needs of both homemakers and employed women while implementing community support programs that validate women's occupational choices. Establishing support groups and counseling services, along with educational initiatives focusing on coping strategies, would benefit both groups. Workplace policies should be designed to promote work-life balance, while community awareness programs should focus on destigmatizing and supporting women's choices regarding employment and domestic roles. | Other | other | en | 0.999996 |
PMC11698272 | Section title: Introduction Educational score: 4.620808124542236 Domain: biomedical Document type: Review Language: en Over the past few years, numerous research studies have focused on enhancing treatment approaches and transitioning from conventional methods to contemporary techniques to minimize harm to healthy cells and specifically target cells during drug delivery processes. 1 Nanomaterials based on drug delivery systems could improve drug transport and provide opportunities for active-targeting of drug delivery and controlled release. 2 Nanotechnology can facilitate delivering the correct drug dose to the right place at the appropriate time inside the body to help the drug concentration and effectiveness during treatment. 3 Magnetic nanoparticles are known as a new class of carriers for drug delivery systems. Paramagnetic iron oxide nanoparticles (MNPs) are unique due to their characteristics, including nano size, magnetic properties, large surface area, simple preparation process, and low toxicity. 4,5 MNPs possess the capability to bind with different compounds, enabling customization for specific uses such as magnetic separation, tissue regeneration, MRI, hyperthermia treatment, catalysis, molecular diagnostics, and drug delivery systems. 1,6 have been extensively researched for their ability to deliver drugs to specific organs within the body when subjected to an external magnetic field. 3 In recent years, polymer-based magnetic nanoparticles, especially cyclodextrins, have gained much attraction for targeting drug delivery. 7 Recently, polymer-based magnetic nanoparticles, particularly those incorporating cyclodextrins, have garnered significant interest for targeted drug delivery. For example, a folic acid-conjugated glycodendrimer featuring a magnetic β-cyclodextrin core has been developed as a pH-responsive system for the targeted delivery of doxorubicin and curcumin, 7 Additionally, pH-responsive β-cyclodextrin-assembled Fe 3 O 4 nanoparticles have been utilized for the selective loading and targeted delivery of stereoisomeric doxorubicin and epirubicin. 8 Furthermore, Fe 3 O 4 @SiN nanoparticles, where Fe 3 O 4 serves as the core and SiO 2 as the shell, have been functionalized with β-cyclodextrin for thymol drug delivery. Another innovative approach involves the fabrication of β-CD-PDA-MNPs through the surface coating of Fe 3 O 4 nanoparticles with polydopamine, followed by functionalization with 6-thio-β-CD and diclofenac as a model drug. 9,10 Lastly, CD-GAMNPs were engineered for targeted anticancer drug delivery of retinoic acid by grafting cyclodextrin onto Arabic gum-modified magnetic nanoparticles (GAMNPs) using hexamethylene diisocyanate as a linker. These developments illustrate the versatility and potential of magnetic nanoparticles in enhancing drug delivery systems, particularly in targeting specific tissues while minimizing side effects. 11 Section title: Introduction Educational score: 3.3707473278045654 Domain: biomedical Document type: Other Language: en These developments illustrate the versatility and potential of magnetic nanoparticles in enhancing drug delivery systems, particularly in targeting specific tissues while minimizing side effects. Section title: Introduction Educational score: 4.421618461608887 Domain: biomedical Document type: Review Language: en Cyclodextrins (CDs) are natural compounds that are made up of starch by the glycosyl transferase enzyme in bacterial degradation (CGTase). 12 The most common natural CDs are alpha-, beta-, and gamma-cyclodextrin, which are obtained from six, seven, and eight units of glucose, which are composed of α-(1,4) glycosidic bonds. 13 CDs have truncated cone shapes with hydrophobic internal cavities and hydrophilic outer surfaces. 14 CDs can accept lipophilic guests with the correct size in the cavity and form inclusion complexes. 15 CDs can improve solubility and stability, prevent volatility, mask flavors, and control the release of the guests. 15–18 CDs can also improve various pharmaceutical qualities, such as drug bioavailability, stability, solubility, and dissolution rate. 19–21 CDs are prominent tools for innovation in drug delivery systems. 3 Among cyclodextrins, β-CD is the most popular compound because of its suitable cavity size, reasonable price, non-toxicity, availability, and biodegradability. 22,23 Section title: Introduction Educational score: 3.995296001434326 Domain: biomedical Document type: Study Language: en To date, many studies have been conducted to introduce a magnetic composite with a facile route of preparation and substantial targeting drug delivery benefits. Among many composites, magnetic chitosan, cellulose, and hydrogel have gained more attention over the last decades. 24–26 However, magnetic cyclodextrin composites with their extraordinary structure may be considered as the better drug carrier due to their ability to form non-covalent interactions with a wide range of hydrophobic drugs, which results in the improved solubility, stability, and transport of lipophilic drugs. However, CDs provide a more controlled release, which is so advantageous when their magnetic composites have been guided to a local site to release a specific dosage of a bioactive substance at a particular time. 27,28 Section title: Introduction Educational score: 3.590243101119995 Domain: biomedical Document type: Other Language: en Amantadine ( Scheme 1 ) is a white, odorless, crystalline powder of the adamantane class of drugs. 29,30 In October 1966, amantadine was approved by the US Food and Drug Administration (FDA) specifically for the treatment of Asian influenza, and in 1976, it received approval to prevent influenza A. 31 However, the FDA coincidentally discovered that amantadine can be used to improve Parkinsonian symptoms. Also, it can be used as monotherapy or in combination with levodopa to control symptoms of Parkinson's disease. 30 It is also known to augment dopamine release and delay its reuptake. 32,33 Section title: Introduction Educational score: 4.3071160316467285 Domain: biomedical Document type: Study Language: en The existing literature lacks reports on the formation of an inclusion complex between adamantine and magnetic carboxymethylated β-cyclodextrin. This study introduces a novel magnetic nanocarrier system aimed at enhancing targeted drug delivery. We achieved this by functionalizing the surface of Fe 3 O 4 nanoparticles with carboxymethyl-β-cyclodextrin (CM-β-CD), creating a nanocarrier that demonstrates “smart” characteristics, allowing for precise control over drug loading and release. Amantadine was selected as a model drug to assess these functionalities. To thoroughly characterize the magnetic nanocarrier's structure and composition, we utilized a comprehensive suite of analytical techniques. Transmission electron microscopy (TEM) provided insights into particle size and morphology, while Brunauer–Emmett–Teller (BET) analysis assessed surface area. Fourier-transform infrared spectroscopy (FT-IR) was employed for functional group identification, and thermogravimetric analysis (TGA) evaluated thermal stability. Magnetic properties were examined using vibrating sample magnetometry (VSM), dynamic light scattering (DLS) analyzed size distribution in solution, and X-ray diffraction (XRD) determined crystal structure. The drug release profile of amantadine from the nanocarrier was meticulously investigated using UV-visible spectrophotometry, followed by the application of mathematical models to elucidate release kinetics and mechanisms. Furthermore, we evaluated the cytotoxicity of the developed nanocarrier against normal human umbilical vein endothelial cells (HUVECs) using the MTT assay, ensuring its biocompatibility. This research not only fills a significant gap in the literature but also contributes to advancing the field of targeted drug delivery systems through innovative magnetic nanocarrier technology. Section title: Materials Educational score: 1.6320600509643555 Domain: biomedical Document type: Other Language: en FeCl 2 ·6H 2 O, FeCl 3 ·6H 2 O, HCl, NH 3 , NaOH, and monochloroacetic acid were purchased from Merck (Germany); amantadine (purity >98%), β-cyclodextrin (β-CD), and carbodiimide were sourced from Sigma-Aldrich. The other reagents and chemicals used were of analytical purity. Section title: Instrumentations Educational score: 4.170392990112305 Domain: biomedical Document type: Study Language: en XRD patterns were recorded using an X-ray diffractometer (STOE, Germany) with Cu Kα radiation at a voltage of 45 kV and a current of 40 mA, scanning the diffraction angle (2 θ ) from 6° to 90° at a rate of 2° min −1 . The morphology of the samples was assessed using transmission electron microscopy (EM 208S) at an accelerating voltage of 100 kV. FT-IR spectra were obtained with an ATR PerkinElmer Spectrum IR Version 10.6.2 over the range of 400–4000 cm −1 . Specific surface areas and pore size distributions were measured using an ASAP 2010 analyzer (Micromeritics, USA). Thermal analysis was conducted with a thermal gravimetric analyzer (TG 209 F3) at a heating rate of 10 °C min −1 from 30 °C to 600 °C. The size distribution of nanoparticles was determined using a dynamic light scattering (DLS) instrument (Microtrac, USA). Magnetization measurements were performed with a vibrating sample magnetometer at room temperature, while UV-VIS analysis was carried out on a UV-Vis spectrophotometer in the range of 200 to 500 nm. Section title: Synthesis of Fe 3 O 4 NPs Educational score: 3.441328525543213 Domain: biomedical Document type: Study Language: en An aqueous solution (50 mL) of ferric chloride (10 mmol) and ferrous chloride (4.26 mmol) was refluxed for 30 min under nitrogen at 85 °C. After 15 min from the zero-time, 7.5 mL of ammonia solution (27%) was poured dropwise for 3 minutes. The color was changed to black immediately. Eventually, an external magnet was applied to collect the precipitates and washed 3 times by deionized water and ethanol. Finally, the precipitates were dried at room temperature. 34 Section title: Preparation of carboxymethylated β-CD (CM-β-CD) Educational score: 4.038552761077881 Domain: biomedical Document type: Study Language: en The carboxymethylated β-cyclodextrin was prepared according to a method that was reported previously. 35 β-CD (2.0 g, 1.76 mmol) and NaOH (1.87 g, 46.5 mmol) were dissolved in 7.4 mL of water at room temperature. Then, 5.4 mL of monochloroacetic acid solution (16.2%) was added to the mixture and stirred at 50 °C for 5 h. After reaching ambient temperature, the pH was adjusted (6–7) by adding HCl. Then, an excess amount of methanol was poured into a neutralized solution at room temperature to precipitate the yield. The white residues were filtered and placed under a hood to dry for 24 hours. Section title: Preparation of Mag/CM-β-CD Educational score: 4.1136980056762695 Domain: biomedical Document type: Study Language: en The magnetic drug carrier was synthesized according to a reported method. 4 A 100 mg of Fe 3 O 4 was suspended in phosphate buffer (2.0 mL, 0.003 M phosphate, 0.1 M NaCl, pH 6) and put in an ultrasonic bath for 10 min at room temperature. Then, carbodiimide solution (0.5 mL, 0.025 g mL −1 in phosphate buffer, pH = 6) was added and sonicated for 15 min at room temperature. Next, CM-β-CD solution (2.5 mL, 150 mg in 3 mL phosphate buffer, pH = 6) was added and sonicated for an extra 90 min at RT. Finally, the resulting magnetic nanoparticles were separated by an external magnet, rinsed five times with phosphate buffer, and dried in a vacuum oven for 24 hours. Section title: Loading of amantadine Educational score: 4.087227821350098 Domain: biomedical Document type: Study Language: en The Mag/CM-β-CD/Amn complex was synthesized using a co-precipitation. 36 A 10 mL methanolic solution of amantadine (0.1 g, 0.66 mmol) was stirred for 15 min at RT. After reaching equilibrium, 100 mg of Mag/CM-β-CD was poured and shaken for 24 h at RT. Then, the mixture was sonicated for 30 min and refrigerated for 12 h. The precipitated magnetic complex was separated using an external magnet, and after washing with methanol, it was placed in a vacuum oven at 40 °C for 24 h to dry. Section title: Loading of amantadine Educational score: 2.770714521408081 Domain: biomedical Document type: Study Language: en To obtain more yields, all procedures for the synthesis of Mag/CM-β-CD, Mag/CM-β-CD/Amn, and drug release were repeated at least 3 times. The results confirm the reproducibility of all assays. Section title: Determination of loading content of drug in Mag/CM-β-CD/Amn Educational score: 4.1072235107421875 Domain: biomedical Document type: Study Language: en 100 mg of Mag/CM-β-CD was dispersed in an amantadine solution (30 mg in 3 mL methanol), shaken for 24 h, and then placed in an ultrasonic bath for 30 min at RT. Next, the Mag/CM-β-CD/Amn were separated using an external magnet. The encapsulation efficiency (EE%) and loading content (LC%) of Mag/CM-β-CD/Amn were determined by analyzing the unloaded concentration of amantadine using UV-Vis spectroscopy at 286 nm and the following equations: 37 1 2 Section title: In vitro drug release study Educational score: 4.107087135314941 Domain: biomedical Document type: Study Language: en The releasing process of amantadine was performed according to a previous study. 38 For this purpose, a dialysis bag consisting of Mag/CM-β-CD/Amn (50 mg/5 mL PBS) was placed in the containers consisting of 200 mL PBS at different pH (5, 7.4, 8) stirred at 37 °C at 300 rpm. The solution absorbance was read at various times (1, 2, 4, 8, 12, 24, 48, and 72 h). For this purpose, 3 mL of the prepared mixture was withdrawn and replaced by the same volume of fresh PBS after measuring the absorbance at 267 nm. The experiments were performed three times. Section title: Kinetic studies of the drug release Educational score: 4.156008720397949 Domain: biomedical Document type: Study Language: en Mathematical studies were adopted to investigate the amantadine release mechanism from Mag/CM-β-CD/Amn. For this purpose, 60% of experimental data obtained from the drug release step was fitted with kinetic models (zero-order eqn (3) , first-order eqn (4) , Higuchi eqn (5) , and Korsmeyer–Peppas eqn (6) ), and their curves are plotted. 3 Q = K 0 t 4 Ln Q = Ln Q 0 − K 1 t 5 Q = K H t 1/2 6 Ln Q = n Ln t + Ln K P where Q is the percentage of released amantadine at time t ; n is the release exponent; K 0 , K 1 , K H , and K P are the rate constant of eqn (3) , (4) , (5) , and (6) , respectively. Section title: Cytotoxicity evaluation Educational score: 4.135997295379639 Domain: biomedical Document type: Study Language: en The cytotoxicity of Mag/CM-β-CD and Mag/CM-β-CD/Amn against HUVECs cell lines (human umbilical vein endothelial cells) was examined using the MTT assay. First, the cell lines were implanted in a 96-well plate and incubated under 5% CO 2 at 37 °C for 24 hours. After cells reached 80% confluence, Mag/CM-β-CD and Mag/CM-β-CD/Amn were added to the wells and incubated in the dark humidified environment along with DMSO (0.05% v/v) at 37 °C for 24 hours. Later, the cell layers were washed with PBS and incubated with 50 μL of the MTT solution (2 mg mL −1 ) for another 4 hours under the same conditions. Therefore, the cell cultures were centrifuged to remove extra supernatants. Finally, the blue-violet MTT crystals were dissolved by adding 200 μL of DMSO and 25 μL of Sorenson, respectively. The absorbance of each cell culture was measured spectroscopically at 570 nm. The absorbance of the control group was considered 100%. The treatments were assayed three times in independent experiments. The cell viability percentage was obtained from eqn (7) : 7 Section title: Results and discussion Educational score: 4.223801136016846 Domain: biomedical Document type: Study Language: en The capability of CDs in the formation of inclusion complexes is one of the most important aspects that makes the compounds desirable in the supramolecular chemistry field. CDs with different cavity sizes can form typical complexes, namely host–guest complexes, with various materials, including organic and inorganic compounds. 39 In this type of complex, the binding of the guest to the host molecules is not a covalent bond. 40 In addition to the importance of size, the binding strength of the complex depends on the interactions between the surface atoms of host and guest molecules. 41 The formation of Mag/CM-β-CD/Amn is presented in Scheme 1 . According to the scheme, the preparation of the Mag/CM-β-CD/Amn consists of three steps including (1) the formation of CM-β-CD by reaction of β-CD with NaOH and then by monochloroacetic acid; (2) the establishment of the linkage of CM-β-CD to Fe 3 O 4 , in this step, carbodiimide was used to activate the OH group of the carboxymethyl group of cyclodextrin to become a better-leaving group while the OH group of the surface of magnetite particles attacks for the formation of Mag/CM-β-CD; (3) the loading of Amn in the carrier using the co-precipitation method. Section title: FT-IR analysis Educational score: 4.3381195068359375 Domain: biomedical Document type: Study Language: en Fig. 1a presents the FT-IR spectra of β-CD, CM-β-CD, Fe 3 O 4, and Mag/CM-β-CD. For β-CD, two bands at 1016 and 1154 cm −1 were assigned to stretching vibrational bands of C–O. The prominent band at 3323 cm −1 was related to the hydroxyl bond (O–H). Furthermore, the band at 2926 cm −1 belonged to the aliphatic C–H bond. For the prepared CM-β-CD, a new peak at 1597 cm −1 related to the C <svg xmlns="http://www.w3.org/2000/svg" version="1.0" width="13.200000pt" height="16.000000pt" viewBox="0 0 13.200000 16.000000" preserveAspectRatio="xMidYMid meet"><metadata> Created by potrace 1.16, written by Peter Selinger 2001-2019 </metadata><g transform="translate scale" fill="currentColor" stroke="none"><path d="M0 440 l0 -40 320 0 320 0 0 40 0 40 -320 0 -320 0 0 -40z M0 280 l0 -40 320 0 320 0 0 40 0 40 -320 0 -320 0 0 -40z"/></g></svg> O bond of the carboxymethyl group, along with all peaks of pristine β-CD, approved the successful formation of CM-β-CD. The band shift to a low wavenumber could be attributed to the carboxylate anion form of the carboxyl functional group due to the use of sodium hydroxide to prepare CM-β-CD. 42 The spectrum of Fe 3 O 4 showed a band at 558 cm −1 assigned for Fe–O bond, the other one at 3400 cm −1 belonged to the O–H bond, which was found at the surface of the synthesized Fe 3 O 4 and indicated the successful synthesis of Fe 3 O 4 . 26 All the mentioned bands for CM-β-CD and Fe 3 O 4 were found in the Mag/CM-β-CD spectrum with little shifts. Besides, the peaks at 1623 cm −1 and 1574 were related to the bounded and unbounded C O of the carboxyl group. The presence of both CM-β-CD and Fe 3 O 4 characteristic peaks in Mag/CM-β-CD and a small shift in the C O bond from 1597 cm −1 to 1623 cm −1 confirmed the successful synthesis of Mag/CM-β-CD. Section title: FT-IR analysis Educational score: 4.228925704956055 Domain: biomedical Document type: Study Language: en The spectra of amantadine and Mag/CM-β-CD/Amn are exhibited in Fig. 1b . The spectrum of amantadine showed two peaks at 3358 and 1522 cm −1 for the stretching and bending vibrations of the N–H bond, respectively. The peak at 1667 cm −1 , belonged to the stretching vibrational band of C–N. Also, the bending vibrational band of CH 2 groups is found at 1428 cm −1 . The band at 2800 cm −1 was related to the stretching vibrational band of CH. The obtained FT-IR spectrum of Amn was similar to a previous report. 43 The FT-IR spectrum of Mag/CM-β-CD/Amn showed different peaks at 2926 (CH), 1667 (CN), 1522 (NH), and 558 (FeO) cm −1 , and the broad peak at 3300–3500 cm −1 belonged to OH and NH bonds. The presence of both amantadine and Mag/CM-β-CD characteristic peaks in the FT-IR spectrum of Mag/CM-β-CD/Amn with small changes in shape and intensity approved successful loading of amantadine in the prepared Mag/CM-β-CD carrier. Section title: XRD analysis Educational score: 4.258660316467285 Domain: biomedical Document type: Study Language: en The crystallinity of Fe 3 O 4, Mag/CM-β-CD, and Mag/CM-β-CD/Amn was investigated using the X-ray diffraction technique. The results are exhibited in Fig. 1 . The XRD pattern of pure Fe 3 O 4 shows six characteristic signals at 2 θ values of 30.12, 35.60, 43.52, 53.86, 56.95, and 62.80, which belong to the planes of (220), (311), (400), (422), (511), and (440), respectively. These data show that the synthesized Fe 3 O 4 has a cubic structure according to the JCPDS card standard and is in good agreement with magnetic particles (Fe 3 O 4 ) that were reported previously. 44,45 As can be seen in the diffractogram, the synthesized Fe 3 O 4 has a crystalline nature. The X-ray pattern of Mag/CM-β-CD depicts three diffraction signals at the values of 30.47°, 35.49°, and 43.55°, which are similar to those of pure Fe 3 O 4 with some modification. This observation confirms the linkage of Fe 3 O 4 to CM-β-CD; however, the peak intensity has been reduced. From the Mag/CM-β-CD/Amn XRD pattern , the main characteristic peak of Fe 3 O 4 is still visible in the resultant magnetic nanoparticles, with shifting to 36.01° at an angle of 2 θ . Besides, the crystalline nature of yield is completely different compared to the starting materials. The XRD pattern of Fe 3 O 4 was completely changed after modification with CM-β-CD and loading of amantadine. These changes in peaks' presence, shape, and intensity exhibit the successful preparation of Mag/CM-β-CD/Amn in a new solid crystalline phase. 46 Section title: Nitrogen adsorption/desorption isotherm (BET analysis) Educational score: 4.23384428024292 Domain: biomedical Document type: Study Language: en Brunauer–Emmett–Teller (BET) surface ( S BET ) area analysis is a sufficient technique to study the size and pores of carriers for drug delivery systems. These characters show a substantial impact on the drug encapsulation process. 47,48 In the present study, BET analysis was run along with the FT-IR technique to acquire more evidence about the successful loading of amantadine molecules in the Mag/CM-β-CD mesh. The porous features of Mag/CM-β-CD/Amn and Mag/CM-β-CD are represented in Fig. 2 . The S BET values and pore volume of Mag/CM-β-CD (59 m 2 g −1 , 0.19 cm 3 g −1 ) and Mag/CM-β-CD/Amn (108 m 2 g −1 , and 0.27 cm 3 g −1 ) were measured. An increase in values was observed after loading amantadine molecules in Mag/CM-β-CD. This phenomenon may be correlated to the formation of new pores after inserting amantadine in the magnetic carriers, resulting in more steric hindrance. 49 The mean pore diameter of Mag/CM-β-CD/Amn is relatively smaller than the pore diameter of pure Mag/CM-β-CD by 9.896 and 13.24 nm, respectively. This observation indicates that the entrapment of drug molecules in the Mag/CM-β-CD pores happened successfully. Besides, N 2 adsorption/desorption plots of Mag/CM-β-CD and Mag/CM-β-CD/Amn show IV isotherm, indicating the mesoporous structure. 7 It seems the formation of Mag/CM-β-CD was applied as a complex magnetic network. So, the entrance of Amn molecules into the network causes the increase of the gap between the network units and leads to an increase in the S BET and total pore volume of the product. Section title: Nitrogen adsorption/desorption isotherm (BET analysis) Educational score: 4.15372371673584 Domain: biomedical Document type: Study Language: en The BET analysis of Mag/CM-β-CD has been compared to the other magnetic carriers, which were reported previously (see Table 1 ). Among the carriers, a magnetic metal–organic framework conjugated with β-CD (Fe 3 O 4 -SiO 2 -MIL-100 (Fe)-β-CD) as a drug delivery system. 3 A polymer of β-CDs (β-CD-P) was synthesized using pyromellitic dianhydride to link the surface of Fe 3 O 4 nanoparticles (Fe 3 O 4 @β-CD-P NPs). Additionally, Fe 3 O 4 -β-CD and Fe 3 O 4 -β-CD-CTD-FA were developed as magnetic nanocarriers, where citric acid and triazine dendrimer were employed to attach folic acid to the surface of Fe 3 O 4 -β-CD. In comparison, Mag/CM-β-CD demonstrated a significantly higher BET surface area and pore volume than the other carriers. The increased porosity enhances drug encapsulation capabilities, which is crucial for improving the efficiency of drug delivery systems. Furthermore, this property indicates that Mag/CM-β-CD could serve as an effective adsorbent in other applications, such as water and air purification. Section title: Determination of magnetic properties Educational score: 4.209688663482666 Domain: biomedical Document type: Study Language: en The magnetization properties of Fe 3 O 4 , Mag/CM-β-CD, and Mag/CM-β-CD/Amn were analyzed using a vibration sample magnetometer (VSM). The results are shown in Fig. 3 . The amounts of 48, 40, and 38 were found for saturation magnetization ( M S ) values of Fe 3 O 4 , Mag/CM-β-CD, and Mag/CM-β-CD/Amn, respectively. The decrease in ( M S ) can be related to the stepwise introduction of dielectric particles to the Fe 3 O 4 surface. Also, the absence of a hysteresis loop ( B r ) and zero coercivity ( H c ) signify that the prepared Mag/CM-β-CD/Amn has a superparamagnetic nature, which is caused by nano-size particles. 3 By coating Fe 3 O 4 with CM-β-CD shells, the value of B r ( y -intercept where x = 0) was decreased. This phenomenon results from reducing the interaction between Fe 3 O 4 nanoparticles. This is a beneficial feature for Mag/CM-β-CD in biomedical applications by dispersing it in water for hours before precipitation. 3 So far, a few researches have been carried out on the formation and usage of magnetic carriers in drug delivery systems. A comparison between the obtained results of the present study and the reported ones is given in Table 2 , The M S value of Mag/CM-β-CD showed better magnetic properties in comparison with magnetic cyclodextrin/maltodextrin nanosponge (magnetic NSs), mefenamic acid-loaded magnetized seed hydrogel (Fe/POSH/MFA), 26 amine-functionalized Fe 3 O 4 /microporous silica nanoparticles (Fe 3 O 4 /MSN-NH 2 ), 52 poly- N -5-acrylamidoisophthalicacid grafted onto Fe 3 O 4 magnetic nanoparticles (MNPs@PAIP-CD), and β-CD surface grafted to Fe 3 O 4 @silica@MOF nanocomposite (Fe 3 O 4 @SiO 2 @MIL-100 (Fe)/β-CD). Therefore, the prepared Mag/CM-β-CD can be considered an appropriate drug delivery agent as it can be separated easily by an external magnet. 53 Section title: TEM imaging analysis Educational score: 4.150989532470703 Domain: biomedical Document type: Study Language: en Fig. 4a exhibits the TEM images and particle size distribution (PSD) of Mag/CM-β-CD and Mag/CM-β-CD/Amn. The results reveal a spherical shape for the magnetic nanoparticles with a mean diameter of 8.34 and 8.49 nm for Mag/CM-β-CD and Mag/CM-β-CD/Amn, respectively. Moreover, they exhibit a narrow size distribution ranging from 6.8 to 11.1 nm for the carrier and 5.6 to 11.3 nm for the final product. The CM-β-CD layer cannot be seen in TEM images. 4 Also, it is proved that the magnetic nanoparticles with zero coercivity and remanence that have a size smaller than 30 nm show superparamagnetic properties. 35 Therefore, the prepared Mag/CM-β-CD/Amn shows this remarkable feature, which is also approved by VSM results. Nanoparticles with spherical shapes are the best candidates for participation in drug delivery systems, as they provide a larger surface area. 7 The morphology and size of the final product indicate that Mag/CM-β-CD have significant capabilities for utilization as drug carriers. Section title: DLS analysis Educational score: 4.145171165466309 Domain: biomedical Document type: Study Language: en To evaluate the hydrophobic diameter of Mag/CM-β-CD and Mag/CM-β-CD/Amn, dynamic light scattering (DLS) analysis was run . According to previous reports, a high aggregation of products is an undesirable property in drug delivery systems. However, Mag/CM-β-CD shows appropriate dispersion with an average particle size of 40.40 nm and a polydispersity index (PDI) of 0.0931. Moreover, Mag/CM-β-CD/Amn shows approximately similar particle size distribution with an average of 41.70 nm. Because of the aggregation of Fe 3 O 4 in water, the diameter of the Mag/CM-β-CD and Mag/CM-β-CD/Amn is quite different from that proven by TEM analysis. 7 Section title: Thermal analysis Educational score: 4.189887523651123 Domain: biomedical Document type: Study Language: en Thermal analysis is an efficient method to investigate thermal stability and further evidence of the formation of the inclusion complex. 54,55 The thermal analysis of amantadine and the Mag/CM-β-CD/Amn are shown in Fig. 5a–c . As shown in Fig. 5a , an initial weight loss occurred at 96 °C due to moisture loss for amantadine. Then, the decomposition is observed at 206–391 °C, where 77.6% of weight is lost. In contrast, the weight of Mag/CM-β-CD/Amn stood quite constant by increasing in temperature, which reveals the high thermal stability of the prepared complex. Meanwhile, the TGA thermogram of Mag/CM-β-CD/Amn reveals the first weight loss (4.41%) at 100–150 °C due to the loss of physically adsorbed water. 28 The second weight loss (8.57%), which occurs at 150–420 °C, is related to the decomposition of organic residue on the nanoparticles. Mag/CM-β-CD/Amn indicated good stability in the range of 420–600 °C. Section title: Thermal analysis Educational score: 4.1648759841918945 Domain: biomedical Document type: Study Language: en DTG diagram is represented in Fig. 5b . Amantadine shows two minor reactions against temperatures at 102.7 and 231 °C and a maximum reaction at 312.42 °C. DTG profile of Mag/CM-β-CD/Amn displays no detectable decomposition. Also, the DTA graph is exhibited in Fig. 5c , where endothermic peaks of amantadine are placed at 143.5, 192.4, 505, and 556.46 °C, and exothermic peaks are located at 238, 288, and 366 °C. However, Mag/CM-β-CD/Amn shows two minor endothermic peaks at 242 and 391 °C, utterly different from the observed peaks for amantadine. DTG and DTA profiles reveal that the prepared inclusion complex is formed successfully, and there is no evidence of uncomplexed drug molecules in the final product. 56 Section title: Drug loading study Educational score: 4.319413661956787 Domain: biomedical Document type: Study Language: en To identify the capacity of Mag/CM-β-CD as a magnetic drug carrier in delivery systems, the co-loading behavior of amantadine on the surface of Mag/CM-β-CD was investigated. 7 For this case, a pre-determined amount of amantadine was loaded on the Mag/CM-β-CD. The concentration of the remaining drug was obtained by spectroscopic method at 286 nm and compared with the calibration curve of amantadine (10–100 mM). The loading percentage and EE% were found to be 26.9% and 81.51%, respectively. The Mag/CM-β-CD carrier shows a remarkable loading capacity. As the interaction of the host and guest molecules is a non-covalent such as van der Waals forces, hydrophobic interaction, hydrogen binding, and London dispersion forces, 41,57 different factors affect the high drug loading: (I) strong hydrogen bonding between the amino (–NH 2 ) group of amantadine and hydroxyl (–OH) or carboxyl (–COOH) groups of Mag/CM-β-CD. In addition, the p K a of amantadine is 10.48, so it has a positive charge in the PBS media (pH = 7.4). 58 During encapsulation, the –NH 2 group of amantadine protonated with a positive charge. On the other hand, the –OH and –COOH groups of Mag/CM-β-CD become deprotonated with many negative charges on the surface, which leads to the formation of an electrostatic interaction between amantadine and Mag/CM-β-CD. 7 (II) The high surface area and total pore volume of Mag/CM-β-CD cause the trapping of amantadine molecules in the pores and spaces of the carrier. (III) The geometrical dimension of the host molecule affects the efficacy of the co-loading process. 59 As can be seen in Scheme 1 , the specific three-dimensional structure of amantadine fit very well with the cavity of CM-β-CD. Accordingly, Mag/CM-β-CD shows high drug encapsulation efficiency. Section title: In vitro amantadine release study Educational score: 4.384119033813477 Domain: biomedical Document type: Study Language: en The in vitro amantadine release from Mag/CM-β-CD was conducted in different pH values simulated for tumor region pH (5), physiological pH (7.4), and pancreas pH (8) at 37 °C to find the cumulative release of the drug in different parts of the human body and examine the pH responsiveness of prepared magnetic nanocarrier. 60 Fig. 6a illustrates the obtained results for the drug release. The profiles show that nearly 20% of amantadine was released in the first hour in all pHs. This could be related to the desorption of amantadine molecules that are entrapped on the surface of the carrier. 61 While 96.6%, 90%, and 52% of the drug are released from Mag/CM-β-CD after 72 hours at pH = 5, followed by pH = 8 and pH = 7.4, which are related to amantadine molecules bound to cyclodextrins. 62 The best result was found for the acidic media because the acidic pH could weaken the π–π interaction between the drug and carrier. 7 The second result for drug release was obtained for pH = 8 with a value of 90%. This phenomenon may be explained by the specific physical property of β-cyclodextrins containing hydrophobic inner cavities. As the pH moves to 8, the concentration of hydroxide ions has risen in the solution. Consequently, –OH groups were replaced with amantadine molecules in the inner cavity of cyclodextrin due to its higher hydrophobic properties and preferred interaction between two hydrophobic molecules. 40 Besides, basic hydrolysis can affect the release of drug molecules from CDs in the basic pHs. On the other hand, the degree of protonation depends on the pH value. As the pH moves to acidic or basic values, the degree of protonation increases, which could weaken the hydrogen bondings between the drug and carrier. In this way, the release profile of amantadine is boosted in non-neutral pHs. At acidic pH, the –NH 2 group of amantadine converts to (NH 3 + ), so it cannot form hydrogen bonding. Besides, the –COOH and –OH groups of carriers deprotonate to (COO − ) and (O − ) cannot participate in the formation of hydrogen bonds. 63 From this point, the charge of both drug and carrier molecules stood neutral at pH = 7.4. It is assumed that the sustainable release of amantadine from Mag/CM-β-CD (52% after 72 hours) at this pH could result from this phenomenon. Because of the acidic environment of tumors, lysosomes, and endosomes, Mag/CM-β-CD, a pH-responsive drug carrier, is a promising candidate to transport cancer drugs to specific regions and release them with high efficiency. 62 Section title: In vitro amantadine release kinetics Educational score: 4.153182029724121 Domain: biomedical Document type: Study Language: en To evaluate the kinetic amantadine release, the results of the last section are fitted to standard mathematical equations, which were introduced previously. 64 Table 3 and Fig. 6b represent the calculated kinetic parameters and curves. The comparison of obtained mathematical data of all curves indicates that the Korsmeyer–Peppas model shows proper fitting to experimental results by higher R 2 values in all pHs. In addition, experimental data for release up to 60% was fitted to the Korsmeyer–Peppas equation. The Ln Q is plotted as a function of Ln t to determine the n (exponent of release) values. The n values signify the mechanism of drug release, where n ≤ 0.43 the release follows the Fickian model; for 0.43 < n < 0.85 follows non-Fickian and n > 0.85 indicates case II models. 65 Section title: In vitro amantadine release kinetics Educational score: 4.164775848388672 Domain: biomedical Document type: Study Language: en As can be seen in Table 3 , all the obtained n values are less than 0.43 at all examined pHs, which corresponds to the Fickian mechanism. The Fickian mechanism is a fundamental concept in drug release that describes the transport of drug molecules through a polymeric medium based on concentration gradients. 66 The Fickian model describes drug release from carrier systems based on diffusion. In other words, diffusion is the primary mechanism governing drug release in this model. In Fickian diffusion, the rate of drug release is independent of the drug concentration within the carrier. This means that even as the drug concentration decreases in the polymer, the release rate remains constant. 67 Section title: Cytotoxicity assay Educational score: 4.251106262207031 Domain: biomedical Document type: Study Language: en To evaluate the biocompatibility of the prepared drug carrier and its inclusion complex, the cytotoxicity of Mag/CM-β-CD and Mag/CM-β-CD/Amn were assessed against the normal cells of HUVEC at different concentrations . HUVECs are utilized to investigate the toxicity of various metallic nanoparticles. 68 As shown in Fig. 7a , Mag/CM-β-CD shows no obvious toxicity, even at high concentrations. This observation can be related to the presence of β-CD in the structure of the prepared drug carrier, which is a non-toxic ingredient. 69 Therefore, Mag/CM-β-CD can be considered a safe and biocompatible carrier in drug delivery systems. Besides, after loading the Amn drug on the Mag/CM-β-CD, the cell viability of the inclusion complex increases to 57.13%. The images of cells treated by Mag/CM-β-CD and Mag/CM-β-CD/Amn are shown in Fig. 7b and c . This observation may be related to the fact that Fe 3 O 4 has unoccupied orbitals that cause damage to the normal cells. After loading amantadine, these orbitals become occupied by amantadine's free electrons, and the cytotoxicity of the product decreases. The same result was reported in a previous paper. 70 Moreover, the prepared Mag/CM-β-CD/Amn shows higher cell viability compared to the other drug-loaded magnetic carriers, such as the magnetic composite hydrogel that was fabricated by the graft copolymerization of itaconic acid (IA) onto starch and alginic acid in the presence of graphene sheets and Fe 3 O 4 nanoparticles for guaifenesin delivery (85% cell viability at 3 μg mL −1 ), 71 and doxorubicin-loaded core–shell mesoporous silica folic acid-grafted nanocomposite for intracellular enzyme-triggered drug delivery (72% cell viability at 125 μg mL −1 ). 72 Magnetic Fe 3 O 4 coated by layered double hydroxide as a methotrexate delivery system for targeted cancer therapy (≈80% cell viability at 120 μg mL −1 ). 73 The low toxicity of Mag/CM-β-CD/Amn, even at the concentration of 1000 μg mL −1 , indicates that the prepared inclusion complex is a safe drug to replace instead of amantadine. Section title: Comparison of the present study with previous studies on amantadine Educational score: 4.306849956512451 Domain: biomedical Document type: Study Language: en To gain more insights into the advantages of the prepared drug delivery systems for amantadine, which were explored comprehensively in this study, we have compared some of the characteristics of the prepared Mag/CM-β-CD with others. In this way, poly( dl -lactic acid)–methacrylic acid nanospheres bound to the chelating ligand diethylenetriaminepentaacetic acid (DTPA) that was synthesized for targeted delivery of amantadine show substantially lower drug encapsulation by 35.84% compared to Mag/CM-β-CD by 81.51%. The low amount of drug encapsulation efficiency leads to the utilization of a higher amount of prepared drug delivery systems to obtain the recommended dosage of amantadine for appreciable affection. Moreover, the particle size of drug carriers is so critical in these types of materials, and these nanospheres were synthesized with a particle size of 81.94 nm, which is dramatically bigger than that of Mag/CM-β-CD. In addition, the cumulative release of amantadine from these nanospheres records just below 10% after 72 h. Even though this carrier shows a more prolonged drug release compared to the Mag/CM-β-CD, it should be considered that this carrier system can't provide a sufficient dosage of the amantadine in a certain region of the body even after 72 hours. 74 Moreover, the amantadine-based ion-pair amphiphiles were synthesized using oleic acid surfactant through a proton transfer reaction between amantadine and oleic acid molecules. These vesicles exhibited a broad size distribution, aggregating at 200–300 nm in aqueous solution, which is significantly larger than the 43 nm size of Mag/CM-β-CD/Amn. This aggregation is an undesirable property in drug delivery systems. Furthermore, the drug loading in the vesicles was found to be 34.87%, which is lower than the encapsulation efficiency (81.51%) achieved by Mag/CM-β-CD. Finally, the release rate of ion-pair amphiphile vesicles was much faster compared to Mag/CM-β-CD, with approximately 65% of amantadine being released in PBS within just 2 hours. After this initial burst, there was no significant further release, and the maximum drug release was around 70% after 6 hours. That has no remarkable difference from the free drug. 75 Section title: Conclusion Educational score: 4.39304256439209 Domain: biomedical Document type: Study Language: en In this study, we successfully synthesized magnetic nanoparticles (Fe 3 O 4 ) conjugated with CM-β-CD for targeted drug delivery applications, specifically focusing on the encapsulation and release of amantadine. The findings demonstrate that the MNPs exhibit a high encapsulation efficiency of 81.51%, attributed to the high surface area of the carrier and the strong interactions between amantadine and the functional groups on the CM-β-CD surface. The pH-sensitive release profile observed in vitro indicates that the MNPs can effectively release the drug in acidic environments, which is particularly relevant for targeting tumor tissues where the pH is often lower than in healthy tissues. The characterization techniques employed, including FT-IR, XRD, TGA, BET, and DLS, confirm the successful formation of the inclusion complex and highlight the favorable physicochemical properties of the synthesized MNPs. The thermal stability of amantadine increased dramatically and showed high particle magnetization. Furthermore, Mag/CM-β-CD/Amn has spherical geometry with a narrow particle size distribution in the nano-sized territory. The superparamagnetic nature of the nanoparticles allows for the potential application of an external magnetic field to enhance targeted delivery, minimizing systemic side effects and improving therapeutic outcomes. Looking forward, the approach of synthesizing magnetic CM-β-CD offers significant opportunities for further development in the field of drug delivery systems. Additionally, the biocompatibility and long-term stability of these carriers in biological systems warrant further investigation to assess their practical implementation in clinical settings. The potential for these designed carriers in medicine is promising, particularly in the treatment of diseases requiring targeted therapy, such as cancer and neurodegenerative disorders. By leveraging the unique properties of magnetic nanoparticles and cyclodextrins, we envision a new generation of drug delivery systems that can provide precise and controlled release of therapeutics, ultimately improving patient outcomes and advancing the field of personalized medicine. Section title: Data availability Educational score: 0.861021101474762 Domain: biomedical Document type: Other Language: en The data presented in this study are available on request from the corresponding author. Section title: Conflicts of interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Review | biomedical | en | 0.999996 |
PMC11698299 | Section title: Introduction Educational score: 3.8259332180023193 Domain: biomedical Document type: Other Language: en The goal for educators in Science, Technology, Engineering and Mathematics (STEM) disciplines is to foster understanding of difficult concepts that are inherent in these disciplines. Some common STEM courses in the undergraduate level are pre-requisites for upper-level courses in the major and for professional schools. As a result, students from diverse backgrounds and majors are enrolled in these courses, particularly physics, general chemistry, general biochemistry, with a high demand for students to comprehend enough material to be proficient at some arbitrary level . Continual student engagement in highly dense informational STEM courses is challenging in the traditional lecture format . To address this, educators have flipped their classrooms in which the lectures are provided online before class and class time is spent on the demonstration of application problems, case studies, question/answer periods, and other activities that engage the students . The addition of added activities in the classroom other than just a lecture promotes student centeredness and increases conceptualization of STEM principles . Flipping the classroom is not a new technique , but has become a more popular pedagogy in the past 15 years. In fact, there are instructional guides for implementing coursework in a flipped classroom format . The outcomes of flipping biochemistry courses at the university and medical school level have resulted in improved student satisfaction and engagement in the course , motivate and promote better learning , and even increase student understanding of the primary research literature . Variants of flipping have also included individual versus cooperative flipped formats , integration with team-based learning , and massive open online courses (MOOCs) . Section title: Introduction Educational score: 1.6161901950836182 Domain: other Document type: Other Language: en The flipped format does not solve all learning problems with students. Some students may not enjoy active learning or collaborate well with others . Additionally, the instructor may not invest enough time and effort in the preparation of in-class instructional material . There is some anecdotal evidence that if a student is enrolled in multiple flipped courses, the student may be overwhelmed with the volume of recorded material to review every day, affecting attitudes with the courses . The change in format, along with perceived extra work outside of the classroom to watch lectures, may produce feelings of anxiety, resistance to change, and adoption problems in students . To avoid or overcome obstacles, instructors should ensure students are well prepared for in-class activities, be organized in their instructional methodology, design learning materials and activities based on student feed-back, develop cooperation and sharing skills, and provide support within the class, especially for those who are struggling to understand the subject matter . Thus, the most important task for the instructor is the refinement of course pedagogy as a continual process to enhance student learning and satisfaction with the course. Section title: Statement of the problems Educational score: 4.11204719543457 Domain: biomedical Document type: Study Language: en Anecdotal statements about traditional lecture indicate that many students are accustomed to this methodology for teaching. However, in our experience there are a few persistent problems associated with the traditional lecture. First, in courses with a high amount of information given in each class period, it is easy for students to be overwhelmed . Overwhelmed students will either “zone out” or get mentally “lost” and rarely re-engage the class. Poorly engaged students lack the learning required to achieve the course objectives . This may lead to a lost opportunity to learn the material. Second, the classroom time is 75 min long, which is beyond the attention span of many individuals concerning the amount and level of material that is required to learn. For some subjects, the twice per week class that is about 1.5 h long per session/class time is optimal , but may be too long for some STEM subjects . Third, students come from a variety of disciplines and may not be as well prepared as their peers, even though they all take the same prerequisite courses such as general chemistry, algebra, calculus, and physics. Due to this variability, learning instruments have been developed to address this problem. For example, the Organic and Biochemistry Readiness Instrument (ORBI) reinforces critical knowledge gaps in inorganic chemistry to prepare students for organic and biochemistry courses . Unfortunately, ORBI nor any similar instrument was not applied here. This course (Biochemistry I) is a requirement for many health professions (medical, dental, pharmacology, etc.) and biochemistry majors. Therefore, students majoring in humanities, for example, are still held to the same academic performance bar as biochemistry majors. To address our observed classroom problems (poor engagement, long class, variable readiness), we asked the following question, “Does changing format and delivery of the material rather than the content increase student comprehension or performance in the course objectives of Biochemistry? This report on the results of our course should reinforce the notion that flipping a biochemistry course facilitates student learning through higher classroom engagement and repeated exposure to fundamental concepts. Section title: Demographics of the biochemistry course Educational score: 2.1051840782165527 Domain: biomedical Document type: Other Language: en The flipped classroom was implemented in a large undergraduate upper-division biochemistry course at a large research-intensive (R1) university in the Midwest region of the United States. The class had 105 students and consisted of 60% male and 40% female. About half of the students were juniors in their 3rd year of studies and 40% were seniors. The remaining 10% consisted of graduate students taking the course as a refresher as part of the PhD academic plan and there was one freshman (Table 1 ). Table 1 Demographics Population % of students Male 60 Female 40 Freshman 0.9 Sophomore 0 Junior 49 Senior 40 Graduate 10 Biochem Major 30 Non major 70 Section title: Demographics of the biochemistry course Educational score: 2.4968409538269043 Domain: biomedical Document type: Study Language: en Thirty percent of the students were biochemistry majors, and a majority of nonmajors had declared their major course of study in Biological Sciences. The remaining minority consisted of students from about a dozen other disciplines (Table 2 ). All the undergraduates had the same pre-requisite requirements whether they were biochemistry majors or non-majors. Pre-tests were not administered to assess baseline knowledge. Table 2 Non-major disciplines Non-majors % of students Biol. Sci 41 Education, human Sciences 1.3 Engineering 8 Microbiology 13 Nutrition 13 Anthropology 1.3 Finance 1.3 Psychology 7 Math 1.3 Animal Sci 9.2 Plant Biology 1.3 Chemistry 1.3 Section title: Ethics approval and consent Educational score: 1.1442233324050903 Domain: other Document type: Other Language: en The Internal Review Board of the university approved protocol IRB #20230622913EX that included all activities and curricula in this course. Students filled out a consent form on the first day of class without the instructor present and administrative staff collected the consent forms which were not available to the instructor until after final grades were submitted. Section title: Traditional lecture format of the Biochemistry course (weeks 8–15) Educational score: 1.3923958539962769 Domain: other Document type: Other Language: en In prior semesters before flipping the course, the scheduled lecture times were every Tuesday and Thursday of the week with classes that were 75 min long throughout a 15-week semester . This is equivalent to a standard three credit-hour course. Recitations are held every Friday afternoon for an hour with the instructor. Recitations do not require attendance and are primarily for those who want extra help in the course. In the traditional lecture format, weekly homework assignments were distributed on each Thursday and were due on the following Tuesday. The homework assignment covered the material presented in the week of when it was distributed. Two teaching assistants were available to grade homework, exams, and meet with students for up to 4 h/week throughout the semester. Lectures were recorded in class and posted to Canvas after class for those who may have missed class and for those who wanted to review the lecture as part of their study habits. iClicker technology was used in lectures to informally assess student comprehension. Table 3 Class organization Monday Tuesday Wednesday Thursday Friday Traditional 75 min Lecture HW due from previous week 75 min Lecture HW passed out and due next Tuesday Recitation by Instructor Flipped Students watch asynchronous online lecture 1. Short quiz on lecture principles 2. Short lecture on difficult concepts 3. Classwork and activities Students watch asynchronous online lecture 1. Short quiz on lecture principles 2. Short lecture on difficult concepts 3. Classwork and activities Recitation by Instructor Fig. 1 Class time organization. The utilization of class time in both the traditional lecture and flipped formats. The lecture is on continuous activity, whereas, the flipped course contains at least 3 different activities Section title: Lectures Educational score: 1.2845884561538696 Domain: other Document type: Other Language: en All lectures were pre-recorded and posted in Canvas, which is the Learning Management System available to all students at the university. Lectures were presented with PowerPoint slides with audio voice-over of the instructor. Each lecture was 30–60 min long depending on the amount of material that was presented and amenable for this type of presentation without student input. Lectures were made available at least 2 days prior to class times which means that all students had the opportunity to review the lectures on Mondays and Wednesdays prior to meeting on Tuesdays and Thursdays. Section title: In-class activities Educational score: 1.6110113859176636 Domain: other Document type: Other Language: en The first activity at the start of class is to take a comprehension quiz based on material that was present in the prior online pre-recorded lecture. The quiz was administered via Canvas and student could easily do this on their phones and laptops. The quiz questions were based on basic comprehension topics that did not involve much memorization or detail. The goal of the quizzes was to ensure that students listened to the recorded lecture and prepared themselves for the discussion and activities in the classroom. The second activity was to ask students about what were the “muddiest” points of the recorded lecture. This was to identify the most difficult concepts that students had trouble understanding. This was asked by a show of hands by the instructor or the instructor putting up a list of topics and students selecting by ranking which topics needed to be discussed the most. This part of the class lasted only about 10–15 min. The remaining 40–45 min of class was spent on the third activity which consisted of doing problems that were similar to the homework problems in the traditional lecture classes. The instruction would often incorporate scaffolding approaches . Normally, the instructor would do one as a demonstration of how to logically approach the problem and derive an answer. The second problem would then be given to the students in which they could work individually or in groups, depending on the difficulty or complexity of the problem. Sometimes the instructor would solve part of the problem and students would be asked to finish. There would often be discussions in class about why and what rationale is inherent in the problem or problem set. Students would each get a worksheet in which they could take notes and self-application of these in-class activities. Section title: iClicker Educational score: 1.0871275663375854 Domain: other Document type: Other Language: en The rationale for the use of iClicker over other response systems is that iClicker is integrated with Canvas and iClicker is widely used at the university in lower-division courses. There were two goals for using iClicker in this course. The first goal was to measure attendance, which was recorded throughout class time. The second goal was to get responses from students on survey questions that were integrated with the in-class activities, including muddiest point discussions and answer surveys for problems that were presented in class. Section title: Grading Educational score: 1.1640347242355347 Domain: other Document type: Other Language: en Four exams were given throughout the course with the first two exam coinciding with the flipped format and the last two exams based in traditional lecture format. These four exams consisted of 68% of the course grade. Other components of the grade include participation via iClicker (9.5%), in-class quizzes (8.5%), and homework during the traditional lecture series (14%). Final grades were distributed on a 10% scale (90–100 = A, 80–89 = B, 70–79 = C, etc.). Section title: Statistics Educational score: 2.505281925201416 Domain: biomedical Document type: Study Language: en This course was administered in the Fall semester (Aug–Dec) of 2023. All single group comparisons were calculated using the Student’s T test. For calculations in which this was not appropriate, comparisons were calculated using the Mann–Whitney algorithm. Multi-group comparisons were performed by one-way ANOVA statistical analyses. All statistical calculations were performed with SigmaPlot version 11.2 software. Section title: Online lecture viewership Educational score: 1.4078153371810913 Domain: other Document type: Other Language: en Canvas is the learning management systems (LMS) used by all courses at the university so students are very familiar with this software. All videos were pre-recorded using a 3rd-party vendor, Yuja, that is integrated with Canvas and videos were posted at least two days prior to meeting in class. Yuja software is able to gather video analytics and, from the eleven flipped courses that were posted, viewership remained consistent throughout the entire length of the video. Most lecture videos had a small drop-off of about 12% in the last few minutes, but overall, viewership is robust . There are a few peaks in the data suggesting that students were rewatching specific segments of the video. This was confirmed in several discussions with students as some of them related that if the material was in any way confusing or difficult to understand, they would re-watch certain segments. Fig. 2 Online recorded lecture viewership. YuJa software embedded in Canvas LMS recorded views every 5 seconds during each lecture and the length of time vs views was normalized to 100%, regardless of play time. The first and last minute of each lecture was not included in the data due to false starts and end-times that were silent due to how the lecture was recorded by the instructor. Peaks within each line plot represent repeated views by students Section title: Quiz and participation performance Educational score: 2.320582389831543 Domain: other Document type: Study Language: en For each flipped class period, one of the first activities of the day was a short 5-min quiz administered on Canvas. The primary purpose of the quizzes were to motivate student to come prepared for class by watching the online lecture. Students were given 5 questions with multiple choice answers that covered the basic concepts of the online lecture made available at least 2 days prior to class. The quiz was timed, and the students had one chance to make their answer selection. Immediately after the quiz, the instructor would review each question with the students to clarify any misunderstandings. Results of the quizzes indicate that students averaged 4.25/5 points per quiz and the standard deviation revealed that the vast majority of students did not score lower than a score of 3/5. However, there were a few outliers in which students scored 0–2 points per quiz. Using a one-way ANOVA test using all pairwise multiple comparison procedures or Dunn’s Method in which the cut-off for significance is p < 0.05 and a Q value of greater than 2.55, all the scores of the following quiz dates were significantly different from each other except for the following comparison days: 5 versus 8, 5 versus 7, 2 versus 9, 1 versus 3 and 4 versus 6 . It is notable that there is a downward trend in the first four days that rebounds again. This may have resulted from the rigor of the quizzes and that students were reminded to avoid complacency after the 4th quiz since these quizzes had a significant impact on final grades. Fig. 3 Quiz and Participation scores during the flipped format. ( A ) In-class quizzes (5 pts each) were administered at the beginning of each class and recorded in Canvas LMS, n = 105 using one-way ANOVA with significance of p ≤ 0.05 and Q>2.55. ( B ) Participation during in-class activities were recorded by iClicker with at least one response required for the full 5 points, n = 105 Section title: Quiz and participation performance Educational score: 2.0330538749694824 Domain: other Document type: Study Language: en Participation was measured with the use of iClicker. In the presentation of individual and group problem solving during class activities, the instructor would post a question with multiple choice answers on the overhead screen in which the students had to select a correct answer. Most students used a cell phone or laptop using iClicker software; however, there were a few students who had the iClicker device and some of these were problematic. To accommodate these few students using outdated iClicker hardware, the instructor had a printed sheet of problem sets and these were turned in at the end of class time and counted toward their participation score. Participation was either all or nothing with the threshold of answering at least one question by iClicker. Typically, there were at least 3 questions for each flipped class day. Using the same ANOVA test to compare multiple groups, a comparison of the medians were significantly different ( p = 0.014), however, the Q values were all too low, so overall, there was no real statistical significant differences between participation levels for each of the flipped class days . Section title: Exam performance Educational score: 2.704357385635376 Domain: other Document type: Study Language: en The course had 4 exams throughout the semester that were graded with equal weight values. The first two exams covered the flipped course and the last 2 exams covered the traditional lecture. Our inquiry was to find out if student performance was improved with the flipped classes. To do this, we compared the same content that was taught in the traditional lecture in pre-covid versus post-covid versus the flipped content . Comparing the traditional lecture pre- and post-Covid for exam 1, the difference is insignificant ( p = 0.148) using the Student’s T test. However, the difference between the post-Covid exam 1 and the flipped class exam 1 was different ( p = 0.002) in that the student scored lower in the flipped class on average by several points . Likewise, for exam 2, the pre- and post-Covid exams were not significantly different ( p = 0.07); however, the exam outcome for the flipped course exam 2 was higher ( p < 0.001) by an average of 9 points . The significantly higher outcome for the exam was correlated to higher satisfaction with the course organization and presentation of material. From our perspective, students were becoming more accustomed to the format of the course and student engagement remained high. Fig. 4 Exam scores. Exam scores from 3 pre-Covid and 3 post-Covid courses in the traditional lecture were compared with the flipped course ( A ) Exam 1 and ( B ) Exam 2. Statistical analysis by Student’s T test followed by the Mann–Whitney U test revealed that the both pre- and post-Covid exams were not significantly different in Graph A (p = 0.148) and in Graph B (p = 0.07). However, the flipped course exam 1 and exam 2 were significantly different from the traditional lectures *p = 0.002 and #p < 0.001 Section title: Mid-course survey Educational score: 1.4437785148620605 Domain: other Document type: Study Language: en During the fourth week of the course during lecture 8, which was in between exams 1 and 2, an informal survey was presented during class and recorded by iClicker. The motivation for this survey was to ensure that the instructor was deploying the course with intended results due to the outcome of the first exam. The first questions was “Is this course structure working for you?” . The result was that 2 out of 3 students (68%) confirmed that the outlay of the course and their ability to learn the material within this structural organization was satisfactory. The second question was “What class format works best for you?” and this focused on what students liked as far as their comfort level with course organization . Approximately the same results were given in that (69%) indicated that the flipped format works best for them. For those who disagreed with this format, 25% confirmed that they enjoyed the traditional lecture and 6% were more comfortable with Zoom only courses. It should be noted that the student’s perception of traditional lecture is from previous courses as traditional lecture had not yet been practiced in this course. Fig. 5 Brief mid-term survey. The questions for ( A ) Is this course structure working for you? and ( B ) What class format works best for you? were informally surveyed in class using iClicker. n = 102 Section title: End-of-semester survey Educational score: 3.069255828857422 Domain: biomedical Document type: Study Language: en During the last week of classes, the students were given an anonymous survey to assess their experience with both the flipped and traditional formats of the same course. Of the 105 students that were enrolled in the course, 57 students responded. The motivation for an anonymous survey was to include an honest write-in answer to the question “What advice would you give the instructor to make this class better?” at the end of the survey. There was no extra credit or grade for this survey and students filled it out on their own motivation to improve the course. Anonymity promoted critically honest answers and their written responses are found in Fig. S1 . A majority of the students enrolled in the course found it difficult to very difficult with 28% responding that it was moderately difficult . Concerning the content, most students (81%) found that the difficulty was on par for an upper-level division biochemistry course with 16% and 4% citing that it was either too difficult or too easy, respectively . After experiencing both flipped and traditional formats of the course, 89% preferred the flipped format, 9% preferred traditional lecture style, and 2% preferred Zoom-delivered course only which is online lecture and no class attendance required . Fig. 6 End-of-semester survey on difficulty, content, and format. ( A ) Students were survey with the question “How difficult is this course?” with 1 = easy, 2 = moderately easy, 3 = slightly challenging, 4 = difficult, 5 = very difficult. ( B ) Students were surveyed with the question “Was the content of this material 1) more difficult than it should be, 2) About right for an upper division biochemistry course, 3) Generally easy”. ( C ) Students were surveyed with the question “What format do you prefer learning this course material 1) Traditional Lecture, 2) Flipped, 3) Zoom only”, n = 57 Section title: End-of-semester survey Educational score: 2.7224814891815186 Domain: biomedical Document type: Study Language: en Activities were an important part of the flipped classroom portions of the course. To determine if the quizzes were actually helpful for the students, about half of those surveyed (53%) said that they were helpful in learning the material . The other 47% responded in either the no or neutral category. Concerning learning the concepts of the course, 86% of those surveyed preferred that the instructor work out the problems with students in class . This consumed most of the time of in-class activity. Group work in-class or out-of-class as well as traditional homework were all less than 10% preferred, strongly suggesting that new concepts are better understood when demonstrated in the classroom setting in an interactive format. Their next question focused on what was most and least helpful in the course. The clear stand-out answer for the most helpful aspect of the course was the instructor doing homework problems and interacting with the class followed by the online lecture . The least helpful aspect of the course was the in-class lecture during the traditional lecture part of the class . It was also interesting to note that no one voted for classwork as the least helpful part of the course. The last surveyed question was “If you had to take the course again, what format would you prefer?” The majority (75%) would have liked to see it flipped, while 21% preferred the present course structure of the first half flipped and the second half traditional. Only 4% would have preferred the traditional format . Fig. 7 End-of-semester survey on course activities and structure. ( A ) Students were surveyed with the question “During the flipped portion of the course, were the in-class quizzes helpful for understanding the material?” ( B ) Students were surveyed with the question “With regards to learning the concepts of biochemistry, which activity do you prefer?” ( C ) Students were surveyed with the question “What was the most helpful activity of the course for learning biochemistry?” ( D ) Students were surveyed with the question “What was the most helpful activity of the course for learning biochemistry?” and ( E ) Students were surveyed with the question “If you had to take the course again, what format would you prefer?” n = 57 Section title: Discussion Educational score: 2.3975565433502197 Domain: biomedical Document type: Other Language: en Students entering this course had no familiarity with the flipped course format. All of them came from traditional lecture pre-requisite courses that used a variety of teaching methods such as backward design, think-pair-share, and other activities that supplemented traditional lecture methodology. Students were a bit slow to catch on to the flipped format and that is evident in lecture 2 which had the lowest viewership of all the recorded lectures. This lecture is also the first “flipped” lecture in the course. In the literature, comparative studies often split biochemistry classes into a flipped class or a blended-learning class with a traditional control . However, this course combined the flipped with traditional teaching methods which is not unprecedented . The reason why we selected this pedagogy is that some of the subject matter tended to be more amenable for better classroom activities while other subjects were more difficult for making meaningful activities. Course material that was dependent on mathematical equations and problem solving tend to be more intuitive for in-class activities, in contrast to material that tends to focus more on pathway analysis. The level of difficulty remained about the same according to the majority of students as this course did not start out easier than it ended. Going forward, we plan to flip the entire class and diversify the types of activities that we are planning for class. Section title: Discussion Educational score: 2.5896987915039062 Domain: other Document type: Study Language: en Was there an improvement in student overall grades? By the second exam, the answer would be yes. However, taking in all the scores accumulated across all 4 exams (2 flipped, and 2 traditional), there was no significant difference in the final grades as compared to previous traditionally taught classes, with the exception in one area. The course had a twofold lower number of failing students at 2% of the class. In contrast, in the prior 3 years, the failure rate was 9%, 8% and 5% for the years 2020, 2021, and 2022 . For these 3 years, the failure rate has been trending downward anyway, so it is impossible to know if the 2% failure rate follows that trend or if the flipped pedagogy actually helped those students who were having major academic problems. In this course, 2% represented 2 students who stopped showing up to class during the traditional lecture and never dropped the course. Therefore, it is probable that the students who were attending class throughout the semester benefited. The cohort of students who earned C grades increased to 21% from 19% in 2022 and 2021 and 12% in 2020. Students earning A and B grades were always high suggesting that the current flipped/traditional pedagogy helped the students who were struggling but had no real impact on high achievers earning A and B scores. Published results from the flipped pedagogy have varied. There are some who argue that even though students are more engaged in the flipped format, there is no actual improvement in student scores , which is seen more in the K-12 classes. This may be attributed to many other factors concerning young children as they live at home with many other things going on. With college students, flipping the class has the benefit of increasing the learning capabilities of those who normally struggle . This is evident in more recent meta-analyses comparing many of these studies to assess college student learning outcomes. The flipped pedagogy is directly linked with increased student learning across a wide variety of STEM courses at the college level, but there is a major caveat to this. Consistently, when instructors do not plan the classroom activities very well, there is no guarantee that the flipped pedagogy will improve student learning . It is easy to fall back on re-lecturing which commonly occurs when there is a lack of activity preparation or poor online lecture quality. From the instructors’ perspective, the amount of work it takes to prepare the course doubles since good quality video must be recorded and the material for class also needs to be prepared . From our experience, developing good worthwhile classroom activities that enhance what the student previously viewed online is the most difficult and challenging aspect of developing and executing a flipped class. One of the major impediments that we encountered was that the classroom had fixed, theater-style seating so group work and dividing the class into subsections was difficult to achieve. All the group work that we used in this course was very transient (think-pair-share) and only utilized 2–3 people in groups due to physical limitations of the physical classroom. Fig. 8 Final grades for this course. Percentage of passing and failing grades of students in the course . It should be noted that years 2020-2022 were traditional lecture and year 2023 was the flipped course. Section title: Discussion Educational score: 2.0085604190826416 Domain: other Document type: Other Language: en The effects of activity and participation in the development for learning and memory retention are well-known for decades . At the college level, high performing students who do well often can conceptualize and understand new information. Students that cannot do this struggle; therefore, approaching a new concept from different approaches can help reinforce learning and memory . Their first encounter with new information occurs during the online lecture, the second encounter is in class, which reinforces it several ways. First, by a concept quiz. Second, by instructional activity and, third, by working alone or in groups with problem solving. We believe that this is why many of the struggling students performed better with the multiple approaches/reinforcements found in the flipped format than they would have in just the traditional lecture format. During the flipped section of the course, students were awarded points for participation in quizzes and using iClicker. In the traditional lecture, students could still participate with iClicker to in-class surveys and for some participation points. In lectures that did not utilize iClicker participation points, attendance decreased by 18% as recorded by iClicker attendance as lecture recordings were still made for review. Section title: Discussion Educational score: 3.9039533138275146 Domain: biomedical Document type: Study Language: en Is there evidence that flipping the classroom improves student learning and retention? In our survey, this pedagogy was effective for the weaker cohort of students. Others who have performed meta-studies to systematically and quantitatively assess the flipped model argue that student performance improves over the traditional lecture model in several disciplines . The addition of pre-class, in-class, and post-class material to support a recorded lecture reinforces concepts that are either difficult to understand or that are easily missed in the traditional lecture. Now specifically in the biochemistry subject material, most instructors and researchers have found that there is improved learning, teamwork, and perception of the subject material . Not all of these and others report improved final grades for their courses. Anecdotal evidence from this author in discussions with other instructors at national conferences focusing on biochemistry education is that there are many flipped/inverted class failures. Reasons for this can vary from preparation of in-class activity to classroom layout. In supplemental Fig. 2 , we provide the in-class material for other instructors to get started. This material is derived from several common textbooks as well as original ideas from the instructors . Feedback from multiple instructors and students within the discipline suggests that our methodology is more successful than in traditional = based biochemistry classes. Section title: Discussion Educational score: 2.0599396228790283 Domain: biomedical Document type: Other Language: en How does technology-based learning (TBL) factor in with the flipped/inverted biochemistry class? We did not incorporate any advanced technology such as virtual reality or animation other than what is provided by iclicker and publisher produced videos. A big advantage to the flipped technique is that there is more time in class to review concepts with any of these technology tools. There are several reports in the literature who all say that the incorporation of TBL has its place and is generally well received. These include animated videos to demonstrate concepts , WeChat platforms , and experimental simulation platforms such as Icourse and DingTalk . TBL may be seamlessly incorporated within the classroom activity and teaching to foster greater understanding and reinforcement of difficult concepts. Section title: Discussion Educational score: 1.4525389671325684 Domain: other Document type: Study Language: en Some of the weaknesses of this course study are apparent. First, the end-of-course survey was entirely voluntary, in which 54% of the students responded. Students that voluntarily respond tend to be high performing, attention-seeking, or have a strong opinion about the course, whereas those who have a neutral feeling about the course tend not to do any extra work or activity. Yet, our sample size can still give adequate guidance for what did and did not work in this combined flipped/traditional lecture class. Data in the impromptu survey aligns well with the end-of-semester survey . Second, this study only encompassed one large class in one semester and not several classes over several semesters. Nonetheless, all of our data, both quantitative and anecdotal, can still give guidance on how to improve the course. Section title: Conclusions Educational score: 2.429732322692871 Domain: biomedical Document type: Other Language: en In a content-heavy course such as biochemistry where there are many new concepts and many “pieces” to understand and even memorize, the preferred execution of the course, according to our data, is to flip the class with an online lecture and then activities in class to challenge what the students learned in the online lecture and to reinforce those concepts. Student participation in activities were higher in the flipped course, and by exam 2, the students understood more of the basic concepts compared to the traditional lecture. Going forward, we intend to flip the entire course with a focus on enriched in-class activities to reinforce learning the concepts of basic biochemistry. Section title: Supplementary Information Educational score: 1.2997462749481201 Domain: biomedical Document type: Other Language: en Supplementary Material 1 | Other | biomedical | en | 0.999995 |
PMC11698300 | Section title: Introduction Educational score: 4.249600887298584 Domain: biomedical Document type: Review Language: en Driven by evolving consumer preferences for convenience, health, and satisfaction, the food product market constantly pushes the envelope of innovation. One area of noteworthy progress has been in functional foods and biopharmaceuticals. These advancements cater to consumers’ inclination toward health-promoting foods that offer potential protection against diseases . Functional foods are those that provide health benefits beyond their basic nutritional value. They can be naturally occurring, nutrient- or ingredient-enriched, and recognized for their diverse health-promoting properties. On the other hand, a nutraceutical is identified as a product extracted or purified from food sources and typically marketed in medicinal forms, which are not commonly associated with traditional food items. The term "nutraceutical" is often used synonymously with functional food, highlighting their shared health-benefiting characteristics. Despite their growing popularity, an acceptable, all-encompassing definition for these terms remains elusive, contributing to their continued interchangeability. The varieties and nuances of functional foods are numerous, ranging from foods naturally containing bioactive compounds to those synthesized to have an increased level of such compounds. The diversity of functional food categories and their examples is further elucidated in Table 1 . Table 1 Different categories of functional foods Category Definition Examples Basic foods Food/ food products that naturally contain the bioactive • Carrots with beta-carotene • Oat bran and barley cereals with beta-glucan • Green vegetables rich in lutein • Fruits, tea, and citrus containing neutralize free radical Processed foods with added bioactive The bioactive does not exist naturally in the food and is added during processing • Orange juice with added calcium • Milk with added omega-3 fatty acids • Salmon and other fish oils rich in omega-3 fatty acids • Cheese, meat products (a good source of Conjugated Linoleic Acid (CLA)) • Soy-based foods with Isoflavones: Daidzein Genistein • Yogurt and other dairy products (essential source of Lactobacillus) Food ingredients synthesized to have more bioactive compounds The level of the bioactive compounds is modified or concentrated beyond its natural level by traditional breeding, special livestock feeding, or genetic engineering • Yogurt with increased levels of probiotics • Tomatoes with increased levels of lycopene • Eggs with increased levels of omega-3 fatty acids • Foods fortified with indigestible carbohydrates Source: [ 1 – 6 ] Section title: Introduction Educational score: 3.934159755706787 Domain: biomedical Document type: Review Language: en Simultaneously, the field of biopharmaceuticals has seen tremendous strides. Biopharmaceuticals, comprising biomolecules such as proteins, nucleic acids, antibodies, enzymes, hormones, and vaccines, have been recognized and utilized for their immense therapeutic potential for decades . However, the efficient preservation and processing of these beneficial products pose a remarkable challenge due to their heat-sensitive nature. Both functional foods and biopharmaceuticals contain bioactive components that, while contributing to their health benefits, are highly susceptible to heat, and therefore, careful selection of drying methods and conditions is required . Section title: Introduction Educational score: 4.048947334289551 Domain: biomedical Document type: Review Language: en Drying, an integral part of the food and biopharmaceutical industry, serves as an effective preservation technique, ensuring a longer and safer shelf-life of the products. The drying process, however, must be conducted judiciously to minimize damage to the heat-sensitive bioactive components . The current review aims to amalgamate the research and advancements in drying methods, shedding light on their suitability for different biomaterials, their associated problems, and strategies to preserve the active ingredients in biopharmaceuticals, nutraceuticals, and functional foods. Section title: Introduction Educational score: 4.050404071807861 Domain: biomedical Document type: Review Language: en This review explores the nature of functional foods and biopharmaceuticals, addressing the challenges of drying these heat-sensitive materials. It will examine various drying techniques used to preserve diverse, valuable functional foods and biopharmaceuticals, elaborating on the advantages and disadvantages of each method. The discussion extends to hybrid drying technologies that enhance product performance and quality . By providing a comprehensive overview of these drying techniques and their applications this review is poised to stimulate further research into developing even more effective preservation methods for these invaluable resources by providing a comprehensive overview of these drying techniques and their applications. Fig.1 Overview of the review methodology Section title: History of Drying of Sensitive Bioproducts Educational score: 4.0783185958862305 Domain: biomedical Document type: Review Language: en The world has witnessed the emergence of new technologies in modern medicine and health care, followed by the Second World War. Freeze-dried plasma and antibiotics were the two remarkable medical advances made during wartime. After the discovery of penicillin by Alexander Fleming in 1928, a series of curious investigations were conducted to stabilize pure penicillin. Later, in 1939, Dr. Howard Florey and Ernst B. Chain, working at Oxford, used freeze-drying to stabilize penicillin, earning them the Nobel Prize in 1945 . Later, numerous research studies were done in the field of drying, and many were primarily focused on drying heat-sensitive products. At the end of the 19th century, spray-drying technology emerged, and a patent was issued for spray-drying liquid eggs. The technique proved suitable for drying heat-sensitive biopharmaceutical products as well. With the advent of technology and research, different modifications and designs were studied in various drying methods to improve the quality and safety of dried products, retaining their functional and nutritional properties. Section title: Major Concerns in Drying of Heat-Sensitive Materials Educational score: 3.940009593963623 Domain: biomedical Document type: Study Language: en In the large-scale production of bioactive ingredients for nutraceuticals and functional foods, drying is a critical operation demanding significant energy. As demonstrated in Fig. 2 , the removal of moisture in the drying process can occur in different ways: simple evaporation as in hot air or vacuum drying, condensation and evaporation as in superheated stem drying, atomization and evaporation as in spray drying, sublimation as in freeze drying, and precipitation as in supercritical fluid (SFC) drying . Several factors, such as temperature, humidity conditions, pressure, and exposure time, can influence the end product's quality and functionality. Although drying's primary objectives include microbial stability, reducing chemical degradation, facilitating storage, and minimizing transportation costs, researchers also aim to develop drying strategies to mitigate the loss and deformation of bioactive compounds in the dried product . Fig. 2 Different mechanisms of removing moisture in the drying process Section title: Major Concerns in Drying of Heat-Sensitive Materials Educational score: 3.970853090286255 Domain: biomedical Document type: Review Language: en Key indicators of product quality include cellular shrinkage, reduced rehydration capacity, absorbency, solid mobility, surface hardening, and the diminution of volatile aromatic compounds. The evolution of drying methods has led to the categorization of drying technologies into four generations. The first-generation drying technologies, being the most rudimentary, primarily relied on natural elements like sun and wind for drying. With the second generation, artificial heat sources such as ovens and stoves were introduced, greatly improving the reliability and control over the drying process. The third generation brought about mechanized drying techniques, employing hot air ovens, spray drying, and drum drying. This generation saw widespread use in industrial settings, demonstrating enhanced efficiency and control over drying conditions. Currently, we are in the era of fourth-generation drying systems, which use advanced technologies like microwave, infrared, radiofrequency, refractance window, heat pump fluid bed drying, and various hybrid systems. The central aim of these fourth-generation systems is to prioritize preserving food quality, ensuring the retention of essential nutritional components and taste attributes [ 17 – 20 ]. With each progressive generation, the field of drying technology becomes increasingly refined, balancing efficiency, energy consumption, and quality retention. Section title: Major Concerns in Drying of Heat-Sensitive Materials Educational score: 4.072020530700684 Domain: biomedical Document type: Study Language: en Drying processes are characterized by conductive and/or convective heat-transfer mechanisms. The primary aim of these processes is to diminish the concentration of residual volatile components in process streams rich in nonvolatile compounds. These procedures facilitate the transfer of energy from the outer surface to the interior of the wet material, resulting in the generation of internal heat within the solid substance. The different types of functional foods, including dairy, meat, grain, and plant-based functional food ingredients, are rich in bioactive elements such as vitamins, essential fatty acids, minerals, antioxidants, etc. These components, however, are highly susceptible to damage from high temperatures. The process of dehydrating these biological molecules may result in substantial chemical, physical, and nutritional degradation, including but not limited to browning reactions, lipid oxidation, colour and aroma depletion, and loss of vitamins and minerals . Section title: Major Concerns in Drying of Heat-Sensitive Materials Educational score: 4.032687187194824 Domain: biomedical Document type: Study Language: en Certain products are solvent-wet forms that are centrifuged before drying to minimize degradation. However, intense evaporation during drying can still cause a carry-over of solid product particles by the vapour flow. This carry-over can cause clogging of the filters and ducts, resulting in damage to the dryer system. Another common issue with biopharmaceutical and functional products is the agglomeration of particles and their hygroscopic nature, often leading to undesired “lumps” in the end product. Moreover, in the case of organic solids, in which the drying process is controlled by the diffusion of the liquid through the solid, larger lumps lead to longer processing times . Section title: Major Concerns in Drying of Heat-Sensitive Materials Educational score: 2.040189504623413 Domain: biomedical Document type: Other Language: en Moving forward, the discussion shifts to hybrid drying systems. These represent an advanced frontier in processing heat-sensitive materials. The forthcoming section will delve into these technologies, focusing on preserving the inherent qualities of functional foods and biopharmaceuticals. Section title: Drying Systems for Heat-Sensitive Biomaterials Educational score: 4.325955390930176 Domain: biomedical Document type: Review Language: en As most functional foods, nutraceutical foods, and biopharmaceutical ingredients are thermos-liable with a tendency for structural and functional deformation at extreme drying conditions, selecting the appropriate drying system is key. These drying methods and strategies are also chosen based on the nature of end products, such as food powders, flakes, leathers, or sheets from juices, purees, pastes, or suspensions . Thermal degradation models for various biomolecules and nutrients are essential for understanding and predicting the behavior of heat-sensitive biomaterials under various temperature conditions . Several numerical models aim to describe the kinetics of degradation reactions, assess the impact of temperature on biomaterial stability, and optimize processing parameters to minimize thermal degradation . Thermal degradation of the primary macro-nutrients such as carbohydrates, proteins, and lipids is sometimes essential for converting them to more digestible forms for enhancing nutrient intake. On the other hand, changes to micronutrients such as vitamins, minerals and other functional micronutrients may significantly affect on their functionality and bioavailability . Table 2 summarizes the thermal degradation mechanism and models of macro-nutrients and micro-nutrients. The following section delves into an array of drying methods commonly used in the food and biopharmaceutical industries, specifically focusing on their application in the drying of functional foods and biopharmaceuticals. These methods are critical for preserving the products' quality, nutritional value, and bioactive properties while ensuring safety for consumption or use. The methods discussed include heat pump drying (HPD), freeze-drying, spray drying, vacuum drying, fluidized bed drying (FBD), superheated steam drying, infrared (IR) drying, microwave drying, osmotic drying, and supercritical fluid drying. Each method will be discussed in detail, highlighting its working principle, advantages, limitations, and particular applications in drying functional foods and biopharmaceuticals. Table 2 Thermal degradation mechanism and models of macro-nutrients and micro-nutrients Nutrient type Mechanism and effects of thermal degradation Models Reference Macro-nutrients Carbohydrate Mechanism • Temperature < 200 °C -loss of free water and hydroxyl groups in physical and polymeric changes • Temperature 220 °C -550 °C -formation of dehydrated anhydrides with structural and chemical changes • Temperatures > 550 °C further carbonization to degrade to smaller molecules CO 2 , H 2 , CH 4 , etc. Effects o Caramelization of carbohydrates leading to the formation of brown color, aroma and flavor compounds o Pyrolysis of carbohydrates, resulting in the breakdown of complex carbohydrates The Arrhenius equation and Reaction rate models: k = k 0 · e −Ea/RT Ea is the activation energy (kJ mol −1), k is the rate constant, and k 0 is the frequency/pre-exponential factor. R is the universal gas constant (8.314·10 −3 kJ mol −1 K −1), and T is the absolute temperature (°K) E.g.: Friedman model, Ozawa model, Kissinger model, Flynn-Wall-Ozawa model, Coast-Redfern model [ 24 – 30 ] Proteins Mechanism • Temperature 100 °C -200 °C -spatial structure changes -thermal aggregation • Temperature > 200 °C – thermal degradation Effects o Denatured protein molecules undergo aggregation or covalent cross-linking, leading to the formation of insoluble protein aggregates o Pyrolysis of proteins, resulting in the breakdown of peptide bonds First and second-order Kinetic Models Arrhenius model and reaction model [ 31 – 33 ] Lipids Mechanism • Thermal oxidation 100 ~ 200 °C • Polymerization Effects o Free radicals formation leading to the formation of off-flavors, rancidity, and potentially harmful compounds such as lipid peroxides o Hydrolysis of lipids, resulting in the free fatty acids Second-order polynomial model Arrhenius model [ 24 , 34 – 37 ] Micro-nutrients Vitamins Mechanism • Thermal oxidation and degradation Effects o Lower bioactivity, irreversible binding to other molecules, or degradation to inactive compounds o 300–500 °C, some vitamins (Vitamin A) decomposes to form aromatic substances Vitamin C, D, & β-carotene- first-order reaction kinetic \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ln\left(\frac{{C}_{t}}{{C}_{0}}\right)=-kt$$\end{document} l n C t C 0 = - k t Where, C 0 -initial concentration of vitamin, C t – measured concentration of vitamin at time t and k temperature- dependent rate constant [ 24 , 38 – 42 ] Minerals Mineral stability and availability are reported to have minimal impact by drying processing than other macro- and micronutrients - Phenols, Flavonoids and Glycosides Mechanism • Maillard reaction Effects o Some polyphenols and flavonoids may increase during drying, but long-term exposure of heat reducing their concentration and bioavailability First-order reaction kinetic Section title: Heat Pump Drying Educational score: 3.8082268238067627 Domain: biomedical Document type: Study Language: en The Heat Pump Dryer System (HPDS) represents an innovative and energy-saving approach to drying and dehydration processes that harnesses low-grade energy to heat the drying medium. Heat pump drying technology is used in high-value foods and biomaterials where low-temperature drying generally ranges from 45 to 70 °C and well-controlled conditions are essential . Its potential as a waste heat recovery system and high drying efficiency have boosted HPD’s popularity . Heat pumps can be classified into different designs, such as gas-engine-driven heat pumps [ 50 – 53 ], ground source heat pumps (GSHP), solar heat pumps [ 54 – 56 ], photovoltaic/thermal (PV/T) heat pumps , chemical heat pumps , and desiccant heat pumps . Section title: Heat Pump Drying Educational score: 4.034559726715088 Domain: biomedical Document type: Study Language: en This technology is particularly suitable for high-value products, as it allows for controlled transient drying conditions in terms of temperature, humidity, and air velocity, thereby improving product quality attributes and reducing drying costs. HPD has proven to be a reliable method for biomaterials or food materials, including aquatic food products with a high content of phenolics, chlorophyll, ascorbic acid, phycocyanin, and antioxidant activity [ 48 , 61 – 64 ]. Some of the advantages of HPD include : Lower energy consumption (about 60%) for each unit of water removed, and therefore, higher energy efficiency with improved heat recovery Well-controlled temperature profiles, making it highly suitable for heat-sensitive high-value products with better quality outcomes Flexibility in drying conditions as it can generate temperatures typically ranging from -20 to 70 °C (with auxiliary heating) and a relative humidity of 15–80% (with a humidification system). Section title: Heat Pump Drying Educational score: 2.7102549076080322 Domain: biomedical Document type: Other Language: en Despite these numerous benefits, HPD also has some limitations. The dryers require regular maintenance of components (compressor, refrigerant filters, etc.), and using CFCs in the refrigerant cycle presents environmental concerns. The technique is also not universally suitable for preserving all bioactive compounds. For instance, HPD can negatively affect ascorbic acid in functional food or biomaterials . Section title: Heat Pump Drying Educational score: 3.8742153644561768 Domain: biomedical Document type: Review Language: en Another notable hindrance to the widespread adoption of HPD is the constraints in achievable drying temperatures and the substantial capital required for setting up the system. However, these challenges do not overshadow the key benefits of this technology. Its ability to precisely control the operating temperature and relative humidity makes it ideal for drying functional foods, yielding minimal discoloration and ascorbic acid degradation. Despite the limits on temperature range, this precision positions HPD as a promising technology for enhancing the preservation of high-value foods and biomaterials. Section title: Freeze Drying Educational score: 3.830122470855713 Domain: biomedical Document type: Other Language: en Freeze drying, also known as lyophilization, is primarily utilized to remove water from sensitive biological molecules. This procedure prevents damage, enabling their preservation in a storable state that can be reconstituted simply by adding water. This method is optimal for preserving biopharmaceutical/nutraceutical products (Table 2 ) like antibiotics, bacteria, vaccines, diagnostic medications, protein-containing, biotechnological products, cells and tissues, and chemicals . Furthermore, freeze-drying is apt for preserving and drying various high-value functional foods like fruits, dairy products, meat proteins, eggs, etc. . Section title: Freeze Drying Educational score: 4.358929634094238 Domain: biomedical Document type: Study Language: en Owing to the water being removed in its frozen state rather than its liquid state, the material's morphology, solubility, and chemical integrity are largely maintained after freeze-drying . Freeze-drying is a three-phase process: initially, the product is frozen, decreasing the temperature to cause most of the water to crystallize, leaving only a small fraction unfrozen and incorporated within the product. Subsequently, the primary drying phase occurs, during which the chamber pressure is reduced to enable sublimation while heat is concurrently supplied to the product. The sublimation process is initiated from the material surface, which is driven by the vapor pressure gradient above the sublimation surface P vi and the evaporated surface P a and the rate of sublimation is computed by Eq. 1 . 1 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$S=\frac{\left({P}_{iv}-{P}_{a}\right)}{\left({R}_{d}+{R}_{d}+{R}_{i}\right)}$$\end{document} S = P iv - P a R d + R d + R i where S is the sublimation rate, kg/(m 2 ·s); R d is the resistance inside the dry layer, m 2 /(Pa·s kg); R s is the resistance to mass transfer from the dry surface to the resublimation surface, m 2 /(Pa·s kg); and R i is the ice sublimation resistance, m 2 /(Pa·s kg). Section title: Freeze Drying Educational score: 1.4226627349853516 Domain: biomedical Document type: Other Language: en And 1a \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${R}_{i}= \frac{\sqrt{{T}_{i}}}{{K}_{i}}$$\end{document} R i = T i K i Section title: Freeze Drying Educational score: 2.8889646530151367 Domain: other Document type: Study Language: en Under the general assumption that the resistance of the convective mass transfer from the evaporation surface to the resublimation surface is negligible, the maximum sublimation rate possible can be computed as: 2 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${S}_{max}= \frac{{P}_{iv}{K}_{i}}{\sqrt{{T}_{i}}}$$\end{document} S max = P iv K i T i Section title: Freeze Drying Educational score: 4.089569568634033 Domain: biomedical Document type: Study Language: en In primary stage drying, there is a moving interface of freeze-dried layer and frozen layer, and there is no distinctive boundary between the first and second phases of freeze-drying . Equations 3a and 3b give the initial conduction heat transfer from the material surface to the sublimation interface and the frozen layer to sublimation interface, respectively . 3a \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${Q}_{d}=\frac{2{\lambda }_{d}}{\left(\nicefrac{1}{\sqrt{\pi {A}_{s}}}\right)-\left(\nicefrac{1}{\sqrt{\pi {A}_{ext}}}\right)}\left({T}_{ext}-{T}_{s}\right)$$\end{document} Q d = 2 λ d 1 π A s - 1 π A ext T ext - T s 3b \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${Q}_{i}=\frac{2{\lambda }_{i}}{\left(\nicefrac{1}{\sqrt{\pi {A}_{f}}}\right)-\left(\nicefrac{1}{\sqrt{\pi {A}_{s}}}\right)}\left({T}_{s}-{T}_{f}\right)$$\end{document} Q i = 2 λ i 1 π A f - 1 π A s T s - T f where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${Q}_{d}$$\end{document} Q d and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${Q}_{i}$$\end{document} Q i are the heat flux through dried layer and frozen layer in (W), respectively; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\lambda }_{d}$$\end{document} λ d and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\lambda }_{i}$$\end{document} λ i are the thermal conductivity of dried layer and frozen layer in (W/mK), respectively; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${A}_{s}$$\end{document} A s , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${A}_{f}$$\end{document} A f , and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${A}_{ext}$$\end{document} A ext are the surface area of the sublimation interface, frozen layer, and external surface in (m 2 ), respectively; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{s}$$\end{document} T s , \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{ext}$$\end{document} T ext , and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{f}$$\end{document} T f are the temperature of the sublimation interface, external surface, and frozen layer in (K), respectively. Section title: Freeze Drying Educational score: 4.307249069213867 Domain: biomedical Document type: Study Language: en In the secondary drying phase, the product's temperature is increased to remove residual moisture, including bound and unfrozen water . The heat transfer rate by conduction can be defined as the heat flux conducted through the frozen layer of the material (Eq. 3b ). This technique has captivated researchers due to its capability to dry materials at lower temperatures, thereby maintaining their original colour, texture, and quality . The application of novel freeze-drying technologies such as Thin film freeze-drying (TFFD) enabled the production of uniform-sized aerosol particles for biopharmaceutical products such as Inhalation-based medication delivery. TFFD has several advantages over traditional freeze-drying processes in biopharmaceutical applications. TFFD uses an intermediate freezing rate, typically between 10 2 and 10 3 k/s, which is faster than standard freeze-drying . This intermediate freezing rate improves the structural integrity and bioactivity of sensitive biopharmaceutical compounds enabling the production of engineered dry powders and facilitating precise dosing. Table 3 illustrates the freeze-drying conditions for different foods with bioactive components in FBD. Table 3 Freeze drying conditions for different foods with bioactive components Product Drying condition Drying Pressure (Pa) References Green banana flours (Starch and crude fibre) Temperature: - 47 to - 50 °C 700 Brazilian ginseng root (beta-ecdysone & fructo-oligosaccharides) Temperature: - 40 °C Atmospheric Symbiotic drink with lactobacillus casei Temperature: - 49 °C 1000 Seabuckthorn berries (phenolic, carotenoids, fatty acids, and vitamin contents) - 20 to - 50 °C shelf plate temperature Atmospheric Blueberries (polyphenols, antioxidant activity, and ascorbic acid) Temperature: - 30 °C Atmospheric Submicron lactate dehydrogenase (LDH) protein particles lyophilization (1 K/min) and spray freeze-drying (SFD) (10 6 K/s), temperature –50 to -140 oC Atmospheric Encapsulated Probiotic bacteria chamber freeze-drier at -80 oC 0.02 mbar Encapsulated Spirulina Maxima in whey protein Temperature: −50 °C 0.04 mbar Monoclonal antibodies formulated with lactose/leucine Temperature - - 100 °C Atmospheric Section title: Freeze Drying Educational score: 4.03585958480835 Domain: biomedical Document type: Other Language: en Among the key advantages of freeze-drying for food and biomaterial drying are: Preservation of structural, biochemical, and immunological characteristics Enhanced viability or activity rates, along with improved textural attributes, owing to drying at low temperatures Effective recovery of volatile substances, maintaining structural integrity, surface area, and stoichiometric balances, leading to high product yield, prolonged shelf life, and decreased weight for easier storage, transportation, and handling Minimal oxidative reactions due to the absence of oxygen during drying, maintaining the quality of the final product. Section title: Freeze Drying Educational score: 4.0061726570129395 Domain: biomedical Document type: Study Language: en However, the broad implementation of freeze-drying is constrained by the significant capital investment required. It is a high-energy, high-cost process for both operation and maintenance. Despite these limitations, freeze-drying remains an effective method for protein powder production. Nevertheless, issues such as ice formation, solute and protein concentration affecting protein stability, and potential cold denaturation during the freezing process are concerns. To address these issues, hybrid techniques such as combined spray- and freeze-drying, thin film freeze-drying, etc., have been developed, which involve spraying the product into a cryogenic medium, followed by the standard primary and secondary drying processes of freeze-drying [ 86 – 90 ]. Section title: Spray Drying Educational score: 2.9711945056915283 Domain: biomedical Document type: Other Language: en Spray drying, a popular particle formation and drying method, is particularly effective for continuously producing dry solids. These can be either powder or agglomerated particles derived from a liquid feedstock . This technology excels when the final product must meet specific quality standards, such as particle size distribution, residual moisture content, bulk density, and particle morphology. Section title: Spray Drying Educational score: 4.400147914886475 Domain: biomedical Document type: Study Language: en The spray drying process involves rapid heat and mass transfer as the liquid feed is atomized into fine droplets and introduced into a hot airstream. The water evaporates from the droplet during this process, and the resulting dried powder is cooled and collected using cyclone separators. Spray drying modelling is one of the most commonly simulated models using computational fluid dynamics (CFD) . The advanced computational power of CFD was reported to be effective in solving very sophisticated models such as the continuous phase flow model, droplet agglomeration models, particle droplet tracking, and wall depositions models . The mechanism of increased surface area for evaporation of moisture from the atomized particles is attributed to the uniform and faster drying of spray droplets. Consequently, a single heat transfer equation can be utilized to model the heat flux to the droplet in the heating period and the following wet bulb temperature period (Eq. 4 ) . 4 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\frac{d{T}_{p}}{dt}=h\left({T}_{g}-{T}_{p}\right)\frac{4\pi {R}_{p}^{2}}{{C}_{pp}{m}_{p}}- \frac{{h}_{l}{m}_{r}}{{C}_{pp}{m}_{p}}$$\end{document} d T p dt = h T g - T p 4 π R p 2 C pp m p - h l m r C pp m p where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{g}$$\end{document} T g and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{p}$$\end{document} T p are the drying medium and spray particle temperature in (K), respectively; R p is the spray particle diameter in m; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${C}_{pp}$$\end{document} C pp is the specific heat capacity of spray particle in (J/kg⋅K); \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${m}_{p}$$\end{document} m p represents spray particle mass; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${m}_{r}$$\end{document} m r is mass flow rate and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${h}_{l}$$\end{document} h l is the latent heat of vaporization in (J/kg). Section title: Spray Drying Educational score: 4.111355781555176 Domain: biomedical Document type: Study Language: en The spray drying technique has widespread application in the biopharmaceutical industry and in drying of encapsulated food ingredients (Table 3 ). It is mainly used for microencapsulating the active ingredients of many biological materials, such as flavours, lipids, essential fatty acids, carotenoids, and more. The spray drying technique with microencapsulation was also reported to be a potential solution for manufacturing food additives for food fortification applications such as minerals . The active ingredient is homogenized in an emulsion, which forms the microcapsules' coating. Subsequently, the active ingredient emulsion is spray-dried (Table 4 ). Table 4 Drying conditions for different encapsulated active ingredients in spray drying Encapsulated ingredient Wall material Air inlet temperature (°C) Air outlet temperature (°C) References Anhydrous milk fat Whey proteins/lactose/ Maltodextrin 160 80 Ethyl butyrate ethyl caprylate Maltodextrin/gum arabic 160 80 Caraway essential oil Maltodextrin/Skim milk powder 175–185 85–95 Cardamom oleoresin Gum arabic/modified starch/maltodextrin 176–180 115–125 Bixin Maltodextrin/gum arabic/modified starch 180 130 d -Limonene Maltodextrin/gum arabic/modified starch 200 100–120 l -Menthol Gum arabic 180 95–105 Black pepper oleoresin Gum arabic/whey protein concentrate 176–180 105–115 Cumin oleoresin Maltodextrin/ gum arabic/modified starch 158–162 115–125 Arachidonyl l -ascorbate Maltodextrin/gum arabic/soybean polysaccharides 200 100–110 Fish Oil konjac glucomannan, Soybean protein isolate, potato starch 200 80 Fish oil Sugar beet pectin/glucose syrup 170 70 Short-chain fatty acid Maltodextrin/gum arabic 180 90 Hawthorn Berry polyphenols β-cyclodextrin, whey protein isolate, gum arabic 165 Lycopene Gelatin/sucrose 190 52 Turmeric oleoresin Maltodextrin/gum arabic 150–200 90 Section title: Spray Drying Educational score: 3.9478180408477783 Domain: biomedical Document type: Other Language: en This prevalent method for drying liquid products has numerous advantages, including: Drying time is comparatively less than other drying methods since the heat transfer rate is high Good reconstitution capacity and product quality Minimal chances of thermal denaturation as the droplet's surface temperature is maintained at the wet-bulb temperature, significantly lower than the drying gas temperature Enhanced bioavailability of active ingredients and controlled release in encapsulated products Improved control over particle size as the feed droplet size can be easily regulated. Section title: Spray Drying Educational score: 2.675661087036133 Domain: biomedical Document type: Other Language: en However, it's essential to note that spray-dried products are thermoplastic and hygroscopic. As such, product recovery post-drying should be done swiftly and carefully to avoid the product sticking to the dryer walls, which could reduce overall efficiency. Moreover, these dried products are highly sensitive to moisture and temperature fluctuations during storage. Therefore, meticulous efforts must be made to maintain precise relative humidity and temperature levels during storage . Section title: Fluidized Bed Drying Educational score: 4.327213287353516 Domain: biomedical Document type: Study Language: en Fluidized bed drying is widely applied in the drying of granular solids in various industries such as food, ceramics, biopharmaceuticals, and for drying phytochemicals like organic acids, carbohydrates, reducing sugars, lipids, and proteins [ 126 – 131 ]. This method is suitable for drying powders in the 50–2000 μm range, thanks to its high heat and mass transfer rates. FBD's effectiveness lies in its fluidization process, allowing for improved drying rates and reduced drying time. The fluidized bed drying process is another multiphase drying model, as the fluid and solid phases are in an interacting continuum. The drying process is governed by the continuum phase heat transfer from the drying medium into the solid phase. Therefore, the general continuum equation for heat, mass and momentum transfer for the fluid medium is set as the boundary conditions for the solid phase drying modelling. The solid phase dying is governed by diffusion equations (Eqs. 5a and 5b ) for energy and mass transfer, respectively . 5a \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\frac{\partial {T}_{m}}{\partial t}=\frac{{\lambda }_{m}}{{\rho }_{m{C}_{pm}}}\frac{{\partial }^{2}{T}_{m}}{\partial {{R}_{m}}^{2}}$$\end{document} ∂ T m ∂ t = λ m ρ m C pm ∂ 2 T m ∂ R m 2 5b \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\frac{\partial {M}_{m}}{\partial t}=Deff\frac{{\partial }^{2}{M}_{m}}{\partial {{R}_{m}}^{2}}+\frac{2}{{R}_{m}}\frac{\partial {M}_{m}}{\partial {R}_{m}}$$\end{document} ∂ M m ∂ t = D e f f ∂ 2 M m ∂ R m 2 + 2 R m ∂ M m ∂ R m where, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${M}_{m}$$\end{document} M m is the moisture content of the material in kg/kg; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{m}$$\end{document} T m is the temperature of the material in K; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${C}_{pm}$$\end{document} C pm is the specific heat capacity of the material; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\lambda }_{m}$$\end{document} λ m is the thermal conductivity of the material; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\rho }_{m}$$\end{document} ρ m is the density of the material kg/m 3 ; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${R}_{m}$$\end{document} R m is the effective radius of the material in m; Deff is the effective diffusivity coefficient m 2 /s. Section title: Fluidized Bed Drying Educational score: 4.064330101013184 Domain: biomedical Document type: Study Language: en In FBD, the product is subjected to a high flow velocity greater than its specific gravity. This flow lifts it above the periphery of the dryer mesh. It then decelerates and falls onto an annular zone between the central core and the equipment wall. This flow pattern establishes a unique solid–fluid suspension, ensuring uniform and faster drying . This drying system has several advantages, such as: Rapid drying speeds, facilitated by superior contact between gas and particles, results in high rates of heat and mass transfer Enhanced thermal efficiency and a reduced flow area in comparison to traditional pneumatic dryers Ease of control of the drying process by controlling the fluidization velocity and pressure drop. Section title: Fluidized Bed Drying Educational score: 4.225531101226807 Domain: biomedical Document type: Study Language: en However, the method does come with its limitations. It involves high power consumption, requiring suspending the entire bed in the gas phase, leading to a substantial pressure drop. There's an increased chance of attrition and, in some instances, granulation or agglomeration. FBD also has low flexibility for the type of product that can be dried (e.g., it is unsuitable for wet products). Furthermore, frequent issues during the drying of phytochemicals include instability within the drying bed, accumulation of products, coating on non-reactive substances, clumping of particles, and potential system failure. Moreover, there can be losses in bioactive components due to thermal degradation . Therefore, precise control of the drying conditions is necessary for such products with bioactive components, as detailed in Table 5 . Table 5 Drying conditions for different foods with bioactive components in fluidized bed drying and superheated steam drying Product and bioactive compound Drying condition (air or superheated steam) References Phytochemicals Inlet temperature: 60 to 180 °C Feed flow rate: 3 to 12 g/min Green vegetables (broccoli) Inlet temperature: 60 to 80 °C Particle size: 1-3 cm Air flow rate: 1-3 m/s Pellet coated pharmaceuticals Inlet temperature: 90 °C Gas flow rate: 50 kg/h Soybeans Inlet temperature: 110–140 °C Air velocity: 2.4–4.1 m/s Probiotic bacteria Inlet temperature: 40 °C Bee pollen Inlet temperature: 40 °C Air velocity: 6.0 m/s Muskmelon seed Inlet temperature: 40–60 °C Air velocity: 7–11 m/s Wheat grains (dietary fibre and polyphenols) Steam temperature: 110 to 180 °C Fish (omega-3 fatty acid) Steam temperature: 300 °C Flow rate: 150 kg/h Beef (Bioactive antihypertensive peptides) Steam temperature: 130 to 180 °C Flow rate: 35 -55 kg/h Shrimps (carotenoprotein, calcium) Steam temperature: 120 to 180 °C Soybeans (Lysine content) Steam temperature: < 135 °C Steam velocity: 3.2 m/s Oats (beta-glucan) Steam temperature: 110 to 160 °C Steam velocity: 0.35 to 1.0 m/s Waxy rice (Amylose content, Gamma-aminobutyric acid) Steam temperature: 130–150 °C Steam velocity: 3.5 m/s Section title: Superheated Steam Drying Educational score: 2.6397831439971924 Domain: biomedical Document type: Other Language: en Superheated steam drying is a non-polluting, safe, and energy-efficient method [ 147 – 149 ]. Its capacity to dry materials at temperatures above 100 °C makes it widely applicable in the food industry, as illustrated in Table 5 . This method offers various benefits, including reduced drying time and dryer size, ease of integration into production lines, and the ability to recover the energy supplied to the dryer in a usable form. Section title: Superheated Steam Drying Educational score: 4.345842361450195 Domain: biomedical Document type: Study Language: en The drying medium in this method is superheated steam, which operates in a closed cycle, picking up moisture from the wet product in the drying chamber and then condensing the evaporated water in a heat exchanger . Since the drying occurs in a closed environment, the probability of oxidative reaction is minimal, preserving the quality and aroma of the dried material . Moreover, superheated steam drying resembles high-temperature short-time (HTST) treatment in which food gets decontaminated while drying . Low-pressure superheated steam is highly suitable for drying heat-sensitive products like fruits and vegetables, herbs, and other bioactive materials. Low-pressure superheated steam drying takes place in the pressure range of 5–10 kPa , at which the steam becomes saturated [ 152 – 154 ]. Compared to hot air-based drying, superheated steam drying has a faster drying rate, as part of the initial accelerated heat transfer is aided by latent heat contributed by the initial condensation and the subsequent free water evaporation (Eqs. 6a and 6b ) followed by the diffusion model (Eqs. 5a and 5b ) . 6a \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathrm{If\,T_{m}}<\mathrm{T_{sat}},\frac{d{M}_{m}}{dt}=\frac{{h}_{f}\left({T}_{sat}-{T}_{m}\right)}{{h}_{l}}$$\end{document} If T m < T sat , d M m dt = h f T sat - T m h l 6b \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathrm{If\,T_{m}}\,=\,\mathrm{T_{sat}},\frac{d{M}_{m}}{dt}=\frac{h\left({T}_{ss}-{T}_{sat}\right)}{{h}_{l}}$$\end{document} If T m = T sat , d M m dt = h T ss - T sat h l where, T m , T sat , T ss are the material temperature, saturation temperature and superheated steam temperature in K, respectively; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${h}_{f}$$\end{document} h f is the film condensation heat transfer coefficient; h is the convective heat transfer coefficient; and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${h}_{l}$$\end{document} h l is the latent heat of condensation/evaporation. Section title: Superheated Steam Drying Educational score: 4.0085039138793945 Domain: biomedical Document type: Study Language: en Various scholars have utilized superheated steam drying to investigate its ability to preserve bioactive components, primarily antioxidant components, in multiple products. These include tea leaves, where studies have shown significant preservation of antioxidant properties compared to conventional oven drying methods , and in other products like onions, where low-pressure superheated steam drying has demonstrated better retention of bioactive components . Another relevant work Suvarnakuta et al. examined the effects of drying methods on the assay and antioxidant activity of xanthones in mangosteen rind. They concluded that hot air drying or low-pressure superheated steam drying at 75 °C is the most suitable drying method to maximize the quantity and quality of mangosteen. Section title: Superheated Steam Drying Educational score: 3.4596989154815674 Domain: biomedical Document type: Other Language: en Superheated steam drying has several advantages over hot air drying, including [ 159 – 162 ]: Improved drying efficiency when compared to other drying techniques, especially with the closed-loop system. Clean process without any emission of flue gases and odor emissions to the environment. Absence of direct contact between the product and hot, oxygen-rich gas, reducing the likelihood of oxidation Beyond drying, hot steam serves as a sterilizing agent Improved control over the drying process by regulating the amount of steam introduced into the compressor, aiding in achieving precise product dryness. Section title: Superheated Steam Drying Educational score: 3.691077470779419 Domain: biomedical Document type: Study Language: en The primary concern with superheated steam drying is the phenomenon known as initial condensation. This occurs when superheated steam comes into contact with a cold solid feed at ambient temperature, leading to vapor condensation on the material surface. This condensed moisture could increase the drying time unless the feed material is preheated by other means. A low-pressure superheated steam system is required to minimize prolonged drying of heat-sensitive bioactive compounds . The full energy efficiency advantage of superheated steam drying can only be fully utilized in a closed-loop system, where the output steam is diverted elsewhere in the processing plant. Such design modifications could add to the system’s complexity and cost . Section title: Infrared Drying Educational score: 3.9765920639038086 Domain: biomedical Document type: Study Language: en Infrared drying technology uses IR energy directly transferred from a heating element to the food, bypassing the need to heat the surrounding air. Thus, it helps to save energy and drying time. In IR drying, the radiant energy penetrates the product and converts it into heat, heating its surface and inner layers. This intense heating produces a higher heat and mass transfer rate than conventional drying methods. Recent research has highlighted this technique's capability to preserve bioactive components in foods post-drying, showing its effectiveness in maintaining the quality of various food products by preserving their phytochemical content and minimizing the loss of antioxidant activity [ 163 – 167 ]. Section title: Infrared Drying Educational score: 4.319711685180664 Domain: biomedical Document type: Study Language: en The drying mechanism is also governed by the diffusion equation as explained in " Fluidized Bed Drying " section, and the energy balance is governed by the conduction, convection and radiation energy as given by Eq. 7 . Lee et al. studied the effects of far-IR drying on the antioxidant and anticoagulant activities of Ecklonia cava (brown seaweed) extracts. Their findings indicated that far-infrared radiation releases and activates low molecular weight bioactive compounds, such as polyphenols, due to its ability to heat materials without degrading their surface molecules . Senevirathne et al. reported that far-infrared radiation drying at 80 °C is an effective and economical method for drying citrus press cakes with minimal loss of antioxidant activity. 7 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\rho }_{m{C}_{pm}\left(\frac{\partial {T}_{m}}{\partial t}\right)={Q}_{m}-h\left({T}_{m}-{T}_{g}\right)+\zeta \sigma \varepsilon \left({{T}_{r}}^{4}-{{T}_{m}}^{4}\right)-{\dot{m}}_{v}\left({h}_{v}-{h}_{d}\right)}$$\end{document} ρ m C pm ∂ T m ∂ t = Q m - h T m - T g + ζ σ ε T r 4 - T m 4 - m ˙ v h v - h d where T m , T g , T r are the material temperature, drying medium (hot air) temperature, and radiation temperature in K, respectively; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${Q}_{m}$$\end{document} Q m is the material energy, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\zeta$$\end{document} ζ is the material shape factor; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sigma$$\end{document} σ is the Stefan-Boltzmann constant, W/cm 2 ·K 4 ; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varepsilon$$\end{document} ε is the emissivity of the material; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${h}_{v}$$\end{document} h v is Latent heat of vaporization, J/g; \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${h}_{d}$$\end{document} h d is the heat of desorption. Section title: Infrared Drying Educational score: 2.1469810009002686 Domain: biomedical Document type: Other Language: en IR drying offers several advantages, including: Reduced drying time due to higher dehydration rates and high heat transfer rates are achievable with compact heaters High energy efficiency Rapid process control while maintaining the final product's quality. Section title: Infrared Drying Educational score: 2.3090901374816895 Domain: biomedical Document type: Other Language: en The IR drying systems suffer from disadvantages, especially for food and biomaterial drying, such as i) browning reactions resulting in darkening, ii) increased hardness, especially with increased IR power, and iii) deterioration of qualitative parameters [ 172 – 174 ]. Section title: Infrared Drying Educational score: 4.154979228973389 Domain: biomedical Document type: Study Language: en Moreover, IR drying is an effective intermittent irradiation method when combined with convective air drying for heat-sensitive materials. An infrared-augmented convective dryer can rapidly remove surface moisture during the initial drying stages, followed by intermittent drying for the remainder of the process. This approach ensures a faster initial drying rate and offers better process control, as the IR power source can be easily cut off in the event of excessively high temperatures in the chamber, preventing overheating of the product. Ratseewo et al. reported that far-infrared radiation drying of pigmented rice enhanced the content of total phenolic, flavonoid, tocopherols, anthocyanins, gallic and ferulic acids, and quercetin compared to traditional hot air drying. Overall, as demonstrated in Table 6 , the IR drying method is reported to be appropriate for drying high-valued heat-sensitive food products. Table 6 Drying of different functional foods with bioactive components in Infrared Radiation drying Product and bioactive compound Drying condition References Ecklonia cava (Brown seaweed) (antioxidants) Temperature: 40 to 80 °C Optimum temperature: 80 °C Citrus press-cakes (antioxidants) Temperature: 40 to 80 °C Optimum temperature: 80 °C Saffron (antioxidants and aroma compounds) Temperature: 50 to 80 °C Optimum condition: 80 °C for 30 s Gamguk flower (herb) ( Chrysanthemum indicum L. ) (phenolic and flavonoid) Temperature: 50 °C Rice hulls (phenolic compounds) Temperature: 100 °C Peanut hulls (antioxidants and radical scavenging activity) Temperature: 150 °C for 60 min Ginkgo biloba seeds (Flavanoids and anti-oxidants) Temperature: 80 °C Garlic (thiosulfinates, phenolic compounds and antioxidants) Temperature: 50 to 80 °C optimum temperature - < 70 °C Section title: Microwave Drying Educational score: 4.297132968902588 Domain: biomedical Document type: Study Language: en Microwave drying, or microwave-assisted drying, is a rapid drying technique extensively used in the food industry. This method involves transmitting microwave energy through the product, generating heat due to dipolar polarization and ionic conduction phenomena. This method is distinguished by its volumetric heating, propelled by electromagnetic radiation at 915 or 2,450 MHz frequencies. The heat is generated by the interaction between microwaves and the material, converting a portion of the electromagnetic energy into heat throughout the volume, primarily heating polar molecules like water in the product . The heat transfer mechanism by internal heat generation results in a volumetric heating mechanism of electromagnetic energy supplied by microwaves. The volumetric heat flux is represented by the Eq. 8 . 8 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V\rho {C}_{p}\frac{\partial T}{\partial t}=V\left[\frac{\partial }{\partial x} \left(\frac{\partial T}{\partial t}\right)\right]+P$$\end{document} V ρ C p ∂ T ∂ t = V ∂ ∂ x ∂ T ∂ t + P where, V is the product volume in m 3 , and P is the Power in W , generated by the absorption of Microwave. This microwave power absorbed by water molecules (polar) is converted to heat. Section title: Microwave Drying Educational score: 4.0824151039123535 Domain: biomedical Document type: Study Language: en Various studies have explored the potential of microwave drying in producing high-quality end products. The utilization of a two-stage microwave power system, which adjusts the power levels during the drying of functional food products, was proposed by . They proposed that adjusting the power levels of microwave energy (1- 2 kW/kg depending on the initial moisture content) could facilitate higher retention of β-carotene in dried carrots. Microwave-assisted vacuum drying has also been recognized as an appropriate drying method for thermolabile products, including certain foods (e.g., cranberries, carrots, garlic, mushrooms) and biopharmaceutical powders and granules . Condurso et al. found that microwave drying considerably increased the concentration of trisulfides and cyclic sulfur compounds, which contribute to the specific aroma of garlic and possess potent anticancer and chemoprotective properties, in Sicilian garlic compared to hot air drying. Moreover, Berteli et al. studied the microwave vacuum drying process for biopharmaceutical granules and found that it is faster than other drying techniques. They highlighted several benefits: Enhanced heat and mass diffusion through biomaterial due to its volumetric heating nature Quicker formation of internal moisture gradients, leading to enhanced drying speeds Accelerated drying rates achieved without raising the surface temperatures Enhanced product quality, making it suitable for heat-sensitive products (such as carrots, garlic, mushrooms). Section title: Microwave Drying Educational score: 2.111964225769043 Domain: biomedical Document type: Study Language: en However, despite these advantages, further research is needed to address specific challenges associated with this method. These include problems such as non-uniform product heating and uneven distribution of the electromagnetic field in a microwave cavity (Table 8 ). Section title: Osmotic Drying Educational score: 3.690117120742798 Domain: biomedical Document type: Other Language: en Osmotic dehydration is a critical process in drying functional foods such as grapes, berries, tomatoes, carrots, and mushrooms, as it minimizes the loss of functional components [ 192 – 196 ]. The technique operates on the principle of osmotic pressure difference caused by the salt and sugar concentration gradient between the cells of the food product and the surrounding medium. This method minimizes organoleptic and nutritional elements in the product, preserving its flavour and nutritional value . Section title: Osmotic Drying Educational score: 4.367519378662109 Domain: biomedical Document type: Study Language: en Singh et al. conducted studies on drying carrots by osmotic dehydration using sucrose (50° to 80°Brix) and salt solutions (5 to 15%). They reported that the drying occurs through a simultaneous process of water loss and solute diffusion, effectively drying the food product without excessive loss of nutrients following the Ficks diffusion equation. The osmotic pressure of the drying surface rises until it reach a critical level as the diffusion proceeds, resulting in cell membrane rupture. This facilitates increased cell permeabilization index which is measured by electro-physical measurements . The chemical potential gradient, closely associated with the concentration gradient, represents the force exerted on each penetrant molecule during osmosis and diffusion. Under constant temperature and pressure conditions, the chemical potential (μ) can be described by the following equation : 9 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mu ={\left(\frac{\partial {E}_{G}}{\partial n}\right)}_{{T}_{i}, {P}_{i}}$$\end{document} μ = ∂ E G ∂ n T i , P i where, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left(\frac{\partial {E}_{G}}{\partial n}\right)$$\end{document} ∂ E G ∂ n is the partial derivative of the ratio of Gibbs free energy and number of moles of the penetrant. The chemical potential in a liquid phase as a function of temperature and water activity is determined by Eq. 10 . 10 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mu =\mu^\circ +RT \,\text{ln}\,{a}_{w}$$\end{document} μ = μ ∘ + R T ln a w where, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mu^\circ$$\end{document} μ ∘ is the standard chemical potential, R is the universal gas constant (J/Kmol), and T and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${a}_{w}$$\end{document} a w are the absolute temperature (K) and water activity of the substance in the liquid phase, respectively. Section title: Osmotic Drying Educational score: 3.994178056716919 Domain: biomedical Document type: Study Language: en García-Segovia et al. investigated the effect of osmotic dehydration on Aloe Vera, focusing on retaining its immunomodulatory, anti-inflammatory, and antibacterial properties. Their research found that optimal results were achieved when osmotic drying was conducted at lower temperatures, specifically at 40 °C, demonstrating the potential for preserving bioactive compounds during the osmotic dehydration process. Section title: Osmotic Drying Educational score: 3.910332202911377 Domain: biomedical Document type: Review Language: en Overall, the osmotic drying process is particularly effective for fruits and vegetables. The technique can dewater these items without compromising their nutritional and functional elements, preserving their inherent health benefits. Moreover, the capability to fine-tune the osmotic solution allows for optimization based on the specific properties of the food product, making it a versatile and efficient drying method. However, the technique has limitations, such as potential changes in texture and the need to remove the osmotic agents from the product after drying, which warrant further research and technological improvements. Also, the diffusion rate of water differs for different materials depending on their composition, geometry, and size, and this limits the drying rates, affecting their nutritional quality and organoleptic properties . Section title: Pressure-Regulating Drying (Vacuum Drying) Educational score: 3.7842090129852295 Domain: biomedical Document type: Study Language: en Leveraging the universal gas laws, where temperature and pressure are directly proportional, pressure-regulating drying, commonly known as vacuum drying, has gained widespread attention among researchers. By reducing atmospheric pressure, vacuum drying enables water to evaporate at lower temperatures, making it an ideal choice for drying heat-sensitive food products like herbs, curry leaves, and carrots. This approach allows for achieving the desired dryness level without compromising the product's quality, as it operates in a pressure-regulated environment [ 204 – 206 ]. Typically, the operating pressure range varies from a vacuum to close to one atmosphere . Section title: Pressure-Regulating Drying (Vacuum Drying) Educational score: 3.711649179458618 Domain: biomedical Document type: Study Language: en Orikasa et al. investigated the effect of vacuum drying on the quality attributes of kiwi fruit. They reported that vacuum drying helps to improve the quality and nutritional value of the dried kiwifruit when compared to hot air drying by retaining l -ascorbic acid, a crucial vitamin. In another relevant study, Šumić et al. noted a remarkable retention of functional elements such as phenols, anthocyanins, and total solids after vacuum-drying frozen sour cherries. Section title: Pressure-Regulating Drying (Vacuum Drying) Educational score: 2.904289960861206 Domain: biomedical Document type: Other Language: en Moreover, the vacuum drying technique offers considerable flexibility and is less costly than freeze drying, making it a preferred choice for many custom or hybrid drying systems to preserve heat-sensitive biomolecules. Examples include vacuum-assisted microwave and vacuum foam drying . Section title: Pressure-Regulating Drying (Vacuum Drying) Educational score: 2.443735361099243 Domain: biomedical Document type: Other Language: en However, while vacuum drying offers several advantages, it's important to consider its potential limitations. Some challenges include the need for specialized equipment to maintain a constant vacuum, potential issues with oxidation, and slower drying times due to reduced pressure. Despite these challenges, the potential for high-quality dried products positions vacuum drying as an attractive method in the food industry. Continuous research and technological improvements can help address these challenges, increasing the efficiency and applicability of this method. Section title: Supercritical Fluid Drying Educational score: 4.116377353668213 Domain: biomedical Document type: Study Language: en Supercritical fluid drying is a relatively new drying method utilized in the food and biopharmaceutical field, especially in the drying of proteins [ 211 – 215 ]. This technique leverages the anti-solvent properties of SCFs to induce protein precipitation and remove water from formulations. SCFs, existing at temperatures and pressures beyond their critical points, exhibit distinctive characteristics of both liquid and gas states. Their density can exceed that of a liquid under increased pressure, yet they maintain the diffusivity and viscosity similar to a gas, facilitating effective mass transfer. When subjected to a supercritical jet of cosolvent, it dissolves the free water in the material and as penetrates deeper to dissolve entrapped water and bound water. The convective mass transfer is driven by the concentration gradient of cosolvent between the material surface and the fluid medium. This mechanism has it’s disadvantages as there is a high risk of removing water-soluble nutrients and bioactive compounds along with the water. Hence, solvent pressure, flow rate, temperatures, etc., impact the techno-functional properties of the dried material. Section title: Supercritical Fluid Drying Educational score: 4.048252105712891 Domain: biomedical Document type: Review Language: en Supercritical carbon dioxide (CO2) is commonly employed in supercritical fluid drying due to its relatively low critical temperature of 31.5 °C, significantly lower than water's 374.4 °C. Additionally, the Food and Drug Administration recognizes it as a safe substance for food treatment applications. However, research in this drying area is somewhat limited, and potential issues such as residual CO2 in the product, which may alter the pH of the end product, need further investigation . SCF drying is primarily utilized for drying foods and biopharmaceuticals where preserving the structures of the material pores is not critical . Some notable patented applications of SFD in drying foods and biopharmaceuticals are detailed in Table 7 . Table 7 Applications of SCD in Foods and biopharmaceuticals Compounds SC-Solvents Reference Protein, peptides, nucleic acids, bacterial cells, antibodies, serums, liposomes, and viruses Near supercritical CO 2 [ 217 – 222 ] β-Carotene, α-tocoferol and rosmarinic acid Supercritical CO 2 Strawberries (ascorbic acid, anthocyanins) Supercritical CO 2 drug substance, liposome CO 2 or other gases /co-solvent (ethanol) Theophylline ethanol/CO 2 Phenolic compounds (gallic acid resveratrol) Supercritical CO 2 Salmon calcitonin Supercritical CO 2 Insulin Supercritical CO 2 Fenofibrate particles Supercritical CO 2 + ethanol Green tea extract Supercritical CO 2 Section title: Supercritical Fluid Drying Educational score: 2.5052597522735596 Domain: biomedical Document type: Other Language: en While supercritical fluid drying presents a new approach for drying functional foods and biopharmaceuticals, several challenges persist. These include the need for high pressure, potential residual solvents in the product, and substantial investment for setup and operation. Section title: Supercritical Fluid Drying Educational score: 4.020581245422363 Domain: biomedical Document type: Review Language: en In conclusion, " Drying System for Heat-Sensitive Biomaterials " section provided a comprehensive review of the several drying methods used in drying food and biopharmaceuticals. It is evident that the preservation and retention of the nutritional value and bioactive properties of functional foods and biopharmaceuticals during drying is an area that needs further research. Our thorough research of the published work also showcased that each reviewed method offers unique advantages and presents certain limitations, influencing its suitability for different applications. Despite the challenges associated with each method, ongoing research and development efforts are continually seeking to optimize these techniques and address their limitations. The following section will build on this foundation to explore hybrid drying methods that combine the strengths of multiple techniques, pointing toward the future of drying technology. Section title: Hybrid Drying Methods: Innovation and Opportunities Educational score: 4.280436992645264 Domain: biomedical Document type: Review Language: en The effectiveness and appropriateness of the aforementioned drying methods depend on the of biomaterial or bioactive compound type, the initial state of the material to be dried, and the desired final product form and functionality. Table 8 provides a comprehensive summary of the various drying methods, highlighting their strengths and limitations and the biomaterials for which each method holds the greatest application potential. As reported in Table 8 , many of these drying techniques have limitations that could be minimized by combining the different techniques to improve the overall drying process, preserving the product integrity, efficacy, and quality of biopharmaceuticals and nutraceuticals while enhancing efficiency and cost-effectiveness. Table 8 A comprehensive summary of the various drying methods, highlighting their strengths and limitations and the suitability for biomolecules or bioproducts Drying Method Suitable Biomolecules/Products Benefits Overall Limitation References Heat Pump Drying High-value foods, aquatic products preserve essential amino acids Lower energy consumption, well-controlled temperature profiles Regular maintenance, environmental concerns, high capital cost Freeze Drying Biopharmaceuticals, high-value functional foods and ingredients such as Gelatin, isolated proteins, probiotics Preserves structure, biochemical and immunological characteristics High energy and cost, ice formation, protein stability issues Spray Drying Microencapsulation of biopharmaceuticals and biomaterials, food additives, gelatins, active biomolecules Rapid drying, good reconstitution capacity, suitable liquid suspensions, higher foam expansion Sensitive to moisture, potential for product sticking, non-uniform particle size, high temperatures driven denaturation Fluidized Bed Drying Granular solids, phytochemicals, coating/tableting for pharmaceutical and probiotics Rapid drying speeds, enhanced thermal efficiency High power consumption, attrition, unsuitable for highly wet products Superheated Steam Drying Fruits, vegetables, herbs, aquatic products Non-polluting, preserves quality and aroma, faster drying rates Complex setup, risk of overcooking, expensive equipment, Infrared Drying Antioxidant-rich foods, herbs, nuts and seeds, green tea, fruit peels Reduced drying time, high heat transfer rates, Uneven heating, high initial setup cost, limited to certain products due to browning reactions and changes to functional properties Microwave Drying Heat-sensitive foods, biopharmaceutical powders. Volumetric heating, enhanced heat and mass diffusion, improved energy efficiency. Suitable for hybrid drying Non-uniform heating, high equipment cost, shielding needed Osmotic Drying Fruits, vegetables for bioactive compounds Minimizes loss of functional components, preserves flavor, suitable as a pre-treatment Texture changes, nutrient leaching, time-consuming [ 243 – 246 ] Vacuum Drying Herbs, heat-sensitive foods, fruits, formulation of proteins High-quality dried products, retains nutritional value, Suitable for hybrid drying for bioactive compounds Expensive equipment, slower drying times, oxidation issues Supercritical Fluid Drying Proteins, peptides, sensitive biomolecules Effective for heat-sensitive materials, minimal nutrient loss, suitable for bioactive compound extractions and hybrid drying High pressure, residual solvents, complex setup, scaling challenges Section title: Hybrid Drying Methods: Innovation and Opportunities Educational score: 2.9346582889556885 Domain: biomedical Document type: Other Language: en The ongoing quest to retain the bioactive properties of foods and biopharmaceuticals during drying has sparked numerous innovations, including developing hybrid drying methods. By integrating two or more existing techniques, these hybrid methods are designed to leverage the strengths of each approach, thereby compensating for their limitations. Section title: Hybrid Drying Methods: Innovation and Opportunities Educational score: 4.239930629730225 Domain: biomedical Document type: Review Language: en The industry and researchers increasingly recognize emerging hybrid techniques such as microwave-assisted vacuum drying, microwave sprouted bed drying, superheated steam fluidized bed drying, vacuum double-drum drying, spray freeze drying, and infrared-assisted drying in functional foods and biopharmaceuticals due to their superior efficiency and performance . The advent of particle engineering, encapsulation, and the development of novel functional food ingredients in biopharmaceuticals have underscored the need for comprehensive research on tailored drying strategies and hybrid methods. Table 9 presents examples of hybrid drying methods and their applications in various functional foods. Table 9 Hybrid drying methods for various functional foods Functional Food Product Drying method and condition Reference Viable Probiotics Fluidized bed drying with encapsulation Egg White Powder Foam mat freeze-drying Lactobacillus plantarum in aloe vera and agave fructans, whey protein Spray Freeze-Drying Apple pomace powder, blueberries Microwave-assisted vacuum drying Biologics and Vaccines Microwave Vacuum Drying Passionflower ( Passiflora alata ) Spray and spouted bed Mexican plum fruit extract Spray Drying and Spout-Fluid Bed Drying Microencapsulation Wolfberry ( Lycium barbarum L. ) Far-infrared radiation heating assisted pulsed vacuum drying (temperature of 65 °C, vacuum pressure for 15 min, and normal pressure for 2 min) Pre-osmodehydrated watermelon CO 2 convective drying with Far-Infrared radiation heating assisted pulsed vacuum drying Potato slices (Phenolic and Flavonoids) Ultrasound-assisted far-infrared radiation drying (ultrasonic resonant frequency of 28 ± 0.5 kHz and temperature of 50 °C) Pear slices (Phenolic and Flavonoids) Contact ultrasound-assisted far-infrared radiation drying (ultrasonic resonant frequency of 28 ± 0.5 kHz and temperature of 30 °C) Garlic Slices (allicin content) Ultrasonic-assisted vacuum drying (ultrasonic resonant frequency of 40 kHz and temperature of 60 °C Acai puree (anthocyanin, phenolic compounds, antioxidants) Infrared-assisted freeze-drying Polyphenol-enriched maple sugar Vacuum double-drum drying (80 °C and 87.99 kPa) Mulberry leaves extract Supercritical fluid extraction and spray drying Chrysanthemum cake (Phenols) Infrared and Hot Air Drying Section title: Novel Drying Techniques Educational score: 4.061942100524902 Domain: biomedical Document type: Review Language: en The novel, fourth-generation dryers primarily focus on product quality, drying efficiency, time and temperature changes. This category's major types of dryers are high-vacuum, microwave, radio-frequency, and refractive window drying . Among them, microwave and radio-frequency drying have gained comparatively faster commercial applications and attention from food processors and researchers over the others. Even though the technologies using electromagnetic heating, such as radio-frequency and microwave drying, have been researched for decades, the commercial application is still lagging behind the other types. The commercial-level scale-up of radio-frequency drying is limited by the large number of parameters that control the drying efficiency, such as dielectric, physical, and thermal characteristics of the biomaterial to be dried, voltage of electrode, electrode distance, etc. All these factors result in non-uniform heating and uneven distribution of temperature . Hence, there is ongoing research on novel drying technologies such as halogen drying and refractive window drying [ 269 – 271 ]. Refractive window drying has recently been researched for its specific indirect heating of the material and its potential application for low-temperature and short-time processes to dry delicate, heat-sensitive products . This novel drying technique is based on all three modes of heat transfer through conduction, convection, and radiation. It is ideally suitable for liquid materials where high moisture material is spread over a thin infra-red film; the refractive indices of the water and the material become similar, reducing reflection at the interface and enhancing the transmissivity of radiant energy to the product. The method is reported to maintain product temperature between 60–70 °C due to evaporative cooling and convective heat transfer to the ambient air above the material . Despite the greater research and development in novel drying techniques, the commercial application of these techniques in the biopharmaceutical and nutraceutical food industries is limited by various factors such as cost, scalability, infrastructure requirement, technical expertise, etc. Section title: Integration of Automation and Control Technologies Educational score: 2.296630620956421 Domain: biomedical Document type: Other Language: en The landscape of drying technologies for functional foods and biopharmaceuticals is transforming substantially by integrating intelligent automation and control technologies. As advancements in artificial intelligence (AI), machine learning, the Internet of Things (IoT), and cyber-physical systems continue, new opportunities for improving precision, efficiency, and sustainability in drying technologies are revealed. Section title: Integration of Automation and Control Technologies Educational score: 2.7190096378326416 Domain: other Document type: Other Language: en Central to this transformation is the role of process automation, which involves using advanced software and hardware to manage and monitor drying processes. Control systems equipped with programmable logic controllers (PLCs) and supervisory control and data acquisition (SCADA) systems offer precise control over process variables such as temperature, humidity, and air velocity. These systems ensure consistent product quality while minimizing energy consumption and waste by maintaining optimal drying conditions. Furthermore, automation remarkably reduces the need for manual supervision, thereby cutting labour costs and human error . Section title: Integration of Automation and Control Technologies Educational score: 3.890397310256958 Domain: biomedical Document type: Review Language: en Implementing AI and machine learning has demonstrated its efficacy across various sectors, including biopharmaceuticals [ 275 – 277 ], drying technologies [ 278 – 280 ], and agri-food quality monitoring [ 281 – 283 ]. Alongside automation, incorporating AI and machine learning within drying technologies has unveiled new avenues for enhancing process efficiency. Machine learning algorithms can analyze historical and real-time data, enabling the prediction of optimal drying conditions and swift responses to changes in process variables. Likewise, predictive models serve to optimize drying schedules, reduce energy consumption, and improve product quality. Moreover, advanced control systems developed with the help of AI and profound learning neural networks can learn, adapt, and make autonomous decisions based on complex data inputs, thus managing the nonlinear and dynamic nature of drying processes [ 278 , 280 , 284 – 286 ]. Section title: Integration of Automation and Control Technologies Educational score: 1.774266242980957 Domain: other Document type: Other Language: en The complexities and scale of modern drying processes necessitate managing and analyzing large volumes of data, a demand met by cloud computing and big data analytics. Cloud computing and big data analytics provide scalable computational resources and tools for extracting valuable insights from complex data sets. Such capabilities support advanced AI and machine learning applications, predictive modelling, and real-time process optimization . Section title: Integration of Automation and Control Technologies Educational score: 2.027900457382202 Domain: other Document type: Other Language: en Smart sensors and IoT technologies complement these developments, facilitating real-time monitoring and control of drying processes. Smart sensors gather granular data on various process parameters and environmental conditions, while IoT ensures interconnectivity among these sensors, forming a comprehensive and synchronized data network . This real-time data fuels AI and machine learning systems, empowering predictive analytics, real-time adjustments, and proactive maintenance. Moreover, IoT integration can extend beyond individual drying systems to include entire production lines or even multiple manufacturing sites, fostering systemic efficiency and coherence. Section title: Integration of Automation and Control Technologies Educational score: 2.9405195713043213 Domain: other Document type: Other Language: en Advancing this integration further, cyber-physical systems (CPS) represent the next fusion level between hardware and software in drying technologies. These systems tightly couple the computational (cyber) elements with the physical components of a drying process. Creating a digital twin – a real-time virtual replica of the physical process – is possible with CPS. Such digital twins can simulate and evaluate different process conditions and control strategies, yielding substantial improvements in system design and operation [ 291 – 294 ]. Section title: Integration of Automation and Control Technologies Educational score: 2.1826794147491455 Domain: biomedical Document type: Other Language: en Ultimately, these integrated advancements in automation, AI, machine learning, IoT, and cyber-physical systems drive the evolution of drying technologies for functional foods and biopharmaceuticals. The continued exploration of these cutting-edge technological advancements will further shape and enhance the efficiency and sustainability of drying processes. Section title: Trends and Research Directions Educational score: 4.036116600036621 Domain: biomedical Document type: Study Language: en Drying technologies for functional foods and biopharmaceuticals have made remarkable strides, yet the future has potential for further innovation and refinement. A fundamental challenge lies in developing drying techniques that balance energy efficiency, cost-effectiveness, scalability, and preservation of nutritional and bioactive properties. To discern patterns and trends of advancement and innovations in the drying of biopharmaceuticals, nutraceuticals, and functional foods, a network visualization map was generated using VOSviewer as shown in Fig. 3 . The figure visualizes the trends in drying of biopharmaceuticals, nutraceuticals, and functional foods over the years classified with keywords/terms with a technique of full counting generating 5 clusters of keywords. Based on the network visualization map, the advancement and innovations landscape in the drying of biopharmaceuticals, nutraceuticals, and functional foods showed that the earlier years of studies and focus were more skewed to the application of spray drying and micro-encapsulated spray-drying for biopharmaceuticals, nutraceuticals, and functional foods. This trend in technology and research has turned more towards hybrid drying systems and the application of machine learning, AI and IoT technology for improved hybrid drying systems for better drying efficiency and techno-functional properties of the final products in recent years. Fig. 3 Network visualization map on advancement and innovations landscape in drying of biopharmaceuticals, nutraceuticals, and functional foods Section title: Trends and Research Directions Educational score: 3.6702072620391846 Domain: biomedical Document type: Review Language: en In the meantime, as discussed in " Advancements and Future Directions in Drying Technoligies " section, the digital age allows further integration of advanced technologies into these drying methods. Artificial intelligence, machine learning, and smart sensor technologies can profoundly transform drying processes. These technologies enable superior control, permit real-time modifications, and facilitate comprehensive optimization of drying processes, effectively ushering in a new era of intelligent and responsive drying techniques. These technologies use advanced sensors, data analytics, automation, and connection to improve drying efficiency, reduce energy consumption, and maintain product quality and safety. Preliminary studies on the IoT-based control system for smart drying technologies demonstrated the potential to preserve food's functional qualities and nutraceutical values, such as rehydration capacity, crude fibre, protein, and vitamin C levels, etc., compared to conventional drying method counterparts . Section title: Trends and Research Directions Educational score: 4.059659004211426 Domain: biomedical Document type: Study Language: en In parallel with technological innovations, the shift towards sustainable production systems necessitates a thorough understanding of the environmental impact and sustainability of drying techniques. This includes an evaluation of energy consumption, water usage, waste production, and how these techniques align with evolving regulatory requirements worldwide. The specific energy consumption (SEC) of drying technologies refers to the energy required to remove a unit of moisture from a product. Even though SEC is considered a good indicator of the energy performance of drying methods, it is often not proportional to the techno-functionality of this drying technology application in biopharmaceuticals and nutraceuticals. Figure 4 compares available data on SEC of different drying methods . For instance, freeze-drying (lyophilization) is often preferred for biopharmaceuticals and certain nutraceuticals despite its relatively high energy consumption compared to other drying methods . It has been reported to have a lower specific energy consumption (SEC) than freeze-drying, although it reduces total phenolic compounds . Consequently, a hybrid infrared-freeze drying method has been reported effective for bioactive compounds to combine the benefits of both techniques, ensuring quality and energy efficiency . Therefore, the choice of drying technology involves a trade-off between energy efficiency (as measured by SEC) and other factors such as product quality, safety, and regulatory compliance. Fig. 4 Comparison of specific energy consumption (SEC) for different drying techniques [ 161 , 174 , 245 , 296 – 299 ] Section title: Trends and Research Directions Educational score: 1.2266972064971924 Domain: other Document type: Other Language: en From an economic perspective, detailed analyses are needed to evaluate the financial aspects of various methods as a function of techno-functionality. These would consider elements such as capital and operating costs and return on investment, providing insights into the economic feasibility of each method. This information would guide industries in making informed decisions on adopting these drying techniques. Section title: Trends and Research Directions Educational score: 3.2575509548187256 Domain: biomedical Document type: Other Language: en Lastly, it is crucial to continue exploring the challenges and limitations inherent in different drying techniques, the potential integration of drying techniques for enhanced quality and sustainability, and the dedication of research efforts to finding potential pathways for digital transformation in the automation of these drying systems. This exploration will shape the evolution of drying technology, ensuring its practical viability and suitability for both functional foods and biopharmaceuticals. Section title: Trends and Research Directions Educational score: 2.612783193588257 Domain: biomedical Document type: Other Language: en Looking ahead, the emphasis should be on developing drying techniques that are not only efficient and sustainable but also economically viable. These methods must retain the quality of end products, ensuring that the therapeutic and nutritional benefits remain intact. Achieving harmony among these aspects will be pivotal in shaping the future landscape of drying techniques in the food, nutraceutical, and biopharmaceutical industries. Section title: Conclusion Educational score: 4.189502239227295 Domain: biomedical Document type: Review Language: en The process of drying functional foods and biopharmaceuticals poses unique challenges to industries due to the heat-sensitive nature of these products. Consequently, selecting the appropriate drying strategy and methods requires careful consideration, as different products require varying initial conditions to maintain their bioactive and functional components. Ongoing research focuses on enhancing existing systems and designing innovative hybrid solutions to improve drying outcomes. Functional foods and biopharmaceuticals are commonly dried under controlled conditions - either at lower temperatures or higher temperatures for brief periods - to safeguard the intrinsic functional properties. Critical to this process is a deep understanding of particle engineering for optimal rheology and microstructure and devising product-specific drying strategies. This understanding is fundamental given that several chemical instabilities, such as oxidation, aggregation, chemical bonding, and glycation, are commonplace in biomolecules. As such, optimizing various drying methods, including freeze-drying, vacuum drying, and superheated steam drying techniques, is essential for each category of these products, necessitating a comprehensive study of their nutritional and functional properties. The ongoing evolution of drying techniques is pivotal for the future of functional foods and biopharmaceuticals, seeking to balance quality retention, efficiency, and industrial feasibility in an ever-changing landscape. This comprehensive account of the advantages and limitations of each commonly used drying method provides researchers with a critical first building block to devise future innovative modifications to push the state-of-the-art into its future for drying products rich in bioactive volatiles. | Review | biomedical | en | 0.999999 |
PMC11698305 | Section title: Introduction Educational score: 4.058829307556152 Domain: biomedical Document type: Study Language: en The environment is getting increasingly contaminated with xenobiotic pollutants, including polycyclic aromatic hydrocarbons (PAHs) mainly due to the expansion and rapid rise in industrialization. These hazardous PAHs are ubiquitous and pose a potential threat to ecosystems including human beings as they are mutagenic, carcinogenic, and endocrine disruptors . Sixteen PAHs are recorded as priority contaminants by the United States Environmental Protection Agency (USEPA) because of their deleterious effects on ecosystems . PAHs are a group of organic compounds composed of two/more merged benzenoid rings. They are ubiquitous in the environment that originate both from natural phenomena such as fires and volcanic activities, and from anthropogenic sources like fossil fuel combustion, carbon black processing, coal tar, and petroleum seepage [ , , , , ]. More aromatic rings, more structural angularity, and higher hydrophobicity make PAHs more electrochemically stable, persistent, and biodegradation resistant making them difficult to degrade . Section title: Introduction Educational score: 4.182358264923096 Domain: biomedical Document type: Study Language: en Zhang and Tao stated that the global PAHs emission was 530,000 tons into the atmosphere resulting from various man-made actions like biofuel combustion (56.7 %) and wildfire (17 %) in 2004. While traffic fuel, and domestic coal burning accounted for 4.8 %, and 3.7 % respectively. China is the major contributor of PAHs emission with 114,000 tons, followed by India with 90,000 tons, the USA contributing 32,000 tons . Through dry or wet deposition processes, atmospheric PAHs accumulate in water, soil, sediment, and vegetation . In fact, soil and sediment are considered as long-term repository of PAHs and, as such, soil can be considered as a representative of the pollution status with respect to the PAHs . The low vapor pressure and high hydrophobicity of PAHs higher benzenoid rings result in their intense adsorption to soil particles . In research by Hoffman et al. 79 %–93 % of PAHs were linked with suspended solids, indicating that their physical state is mostly solid. The absorption and translocation of PAHs by plants can result in groundwater and food contamination as a result of their accumulation in soil. Exposure to PAHs is inevitable and primarily occurs through ingestion, inhalation, and dermal contact . One cigarette can introduce 20–40 ng of benzo [a]pyrene to smokers, while non-smokers can expose themselves to up to 70 % of their PAHs through their diet . Section title: Introduction Educational score: 4.638736248016357 Domain: biomedical Document type: Review Language: en Conventionally, PAHs are categorized into two groups based on their molecular weight. The low molecular weight PAHs (LMW-PAHs) include naphthalene (NAP), acenaphthene (ACE), fluorene (FLR), phenanthrene (PHE), and anthracene (ANT), all of which contain fewer than four rings. The high molecular weight PAHs (HMW-PAHs), which contain four or more rings include compounds such as pyrene (PYR), chrysene (CHRY), fluoranthene (FLU), benzo [a]anthracene (BAA), benzo [a]pyrene (BAP), benzo [b]fluoranthene (BBF), benzo [k]fluoranthene (BKF), dibenzo [a,h]anthracene (DBA), benzo [g,h,i]perylene (BghiP), and indeno [1,2,3-c,d]pyrene (ICP) . HMW-PAHs, including PYR, BAP, and BBF, are generally resistant to microbial degradation due to their low solubility and bioavailability, making them persistent in the environment, resistant to degradation and prone to bioaccumulation . BAP is linked to cardiopulmonary disorders, psychiatric conditions, and various cancers, including skin, lung, bladder, and gastrointestinal cancers . NAP, PYR, FLR, and ANT have been associated with pulmonary disorders, while CHRY induces oxidative stress and cytotoxicity in human hepatocytes . BAA, BAP, and NAP are known to be embryotoxic as reported in animal studies . Skin contact with PAHs like NAP, ANT, and BAP can cause irritation, allergic reactions, and inflammation . PAHs such as PHE and FLR induce oxidative stress and inflammation in human lung epithelial cells . PAHs are associated with skin, bladder, lung, and gastrointestinal cancers. Short term exposure to PAHs leads to headaches, nausea, and eye irritation, whereas long-term contact causes respiratory difficulties, lung infection, asthma, and various cancers . PAHs are carcinogenic due to the presence of bay or K region in their molecular structure, directly associated with the generation of bay or K region epoxides, which are extremely reactive and have high affinity towards mammalian DNA . Furthermore, this might lead to the creation of DNA adducts, which can alter normal cells into tumorigenic cells, exacerbating the health hazards linked to PAHs . Fig. 1 displays the interactions between PAHs and DNA and other cellular organelles, specifically demonstrating cytotoxicity and genotoxicity. Remediation measures are implemented to address these problems, combat PAH contamination, and protect both humans and the environment . Several techniques for reducing the toxicity of PAHs by degradation or transformation, including physical, chemical, and biological mechanisms that can be used to protect the ecosystem and eradicate the toxicity of PAH contamination, which is crucial for remediation . Fig. 1 Toxicity of PAHs in soil and marine ecosystem. Fig. 1 Section title: Introduction Educational score: 4.616772651672363 Domain: biomedical Document type: Study Language: en Nanomaterials have drawn significant attention due to their unique properties which motivates for potential applications, particularly in bioremediation . Their small size and large surface area-to-volume ratio offer distinct advantages for increasing the adsorption and biodegradation of hazardous contaminants like PAHs in contaminated soil . However, the nanomaterials have certain limitation such as nanotoxicity, antimicrobial properties, high production cost, and poor eco-sustainability. Therefore, nanomaterials such as carbon nanotubes (CNTs), biopolymers, metal-oxide, and nanoscale zeolites, combined with microorganisms, provide a sustainable, eco-friendly, and resourceful approach to remediation . Nanoparticles (NPs) are particularly suitable for PAH bioremediation due to their larger surface area, offering abundant active sites for PAH adsorption . They immobilize and concentrate PAH molecules through interactions like Van der Waals forces, hydrophobic interactions, and π-π stacking facilitating degradation . Some nanomaterials also possess catalytic properties, accelerating PAH breakdown. Yang et al. found that the photocatalytic degradation of FLT in soil was facilitated by a graphitic carbon nitride/iron (III) oxide (g-C3N4/α-Fe2O3) photocatalyst when exposed to sunlight. A dual-doped FeCo/NC catalyst exhibited 24 % better catalytic performance compared to catalysts doped with only Fe or Co, this catalyst was capable of effectively removing 98.87 % of ANT from the soil within 6 h . The interaction between microbes and nanomaterials is complex and varies based on bacterial strain and NPs properties, with mechanisms suggesting bacteria may secrete enzymes immobilized on nanomaterials to aid PAH adsorption and degradation . S-layers and lipopolysaccharides in bacterial cells play a crucial role in NPs attachment and contaminant degradation, affecting biofilm development and microbial colonization. Combining nanomaterials with biochar, enhances bioremediation by increasing porosity and surface area, promoting microbial colonization and PAH adsorption . Nanomaterials can also be designed for the controlled release of agents or enzymes, allowing sustained PAH degradation over time. The synergistic effect between nanomaterials and microorganisms improves PAH uptake and degradation, while the easy dispersion of NPs in the environment ensures better distribution and accessibility to contaminated areas. Section title: Introduction Educational score: 4.126054763793945 Domain: biomedical Document type: Review Language: en Most reviews in the scholarly databases focused on either nanomaterial-based remediation or microbe-mediated PAHs remediation, rather than the combined approach of bioremediation and nanomaterial application. Very few articles addressed the integration of these two remediation approaches . Basak et al. provides the first review offering information on the global use of functionalized NPs for aromatic hydrocarbon remediation. However, none of the reviews provide a clear view on how much the efficiency of PAHs degradation increases while incorporating nanomaterial in bioremediation. There is a lack of systematic reviews, current research compilation, and secondary data analysis on how nanomaterials enhance bioremediation for eliminating PAHs. As such, no strategies for nano-bioremediation of PAHs have been mentioned so far. To overcome this literature gap, this review offers an overview of how the application of nanomaterials influences bioremediation. It also discusses the current research scenario focusing on emerging trends in the use of specific types of PAHs, nanomaterials, and microbes. Section title: Introduction Educational score: 4.07945442199707 Domain: biomedical Document type: Review Language: en The primary objective of the article is to systematically review studies involving both bioremediation and nano-bioremediation of PAHs, discussing the different nanomaterials used and their attributes. It investigates how these nanomaterials influence microbial degradation, thus improving the remediation of PAHs in both liquid and soil environments. Another objective of the study to identify current research trends and international collaborations on this topic. The paper also focuses on different strategies of microbes-mediated nanomaterial for PAHs degradation, highlighting the synergistic effects and mechanisms through which nanomaterials enhance microbial degradation of PAHs. Additionally, it addresses the challenges and future direction involved in using nanomaterials and their implications for remediation. Section title: Methodology Educational score: 4.073652744293213 Domain: biomedical Document type: Study Language: en A comprehensive and impartial systematic literature search was conducted using Web of Science, Scopus, and Google Scholar for the keywords “Nanomaterials”, “nanoparticles”, “nanotechnology”, “bioremediation”, “microbial degradation”, “biodegradation”, “Polycyclic Aromatic Hydrocarbons”, and “PAHs” from 2013 to 2023. Boolean search terms combined “AND” logic to widen the scope and “OR” logic within each category to limit irrelevant papers. A total of 4731 articles were exported from the mentioned databases. The review focused on current experimental research, so review papers, book chapters, and duplicates were excluded during the screening process. This filtering resulted in 360 research articles being retained. After reviewing the abstracts and full texts, 26 research publications were selected based on criteria such as the use of standard analytical methodologies and efficient PAH measurement instruments. Additionally, each article included information on the bioremediation and nano-bioremediation PAH degradation percentages for better understanding and analysis. The articles were precisely analyzed for specific data such as the percentage of removal, and the initial and final concentrations of PAHs. If the articles did not directly mention this information but depicted it, the data was extracted directly from the articles by using software like GetData Graphical Digitizer when necessary. The inclusion criteria were directed toward only those datasets that provide a direct comparison between nano-bioremediation and traditional bioremediation under the same experimental conditions. The methodologies and filters used during the literature search are followed by a Prisma flowchart . Fig. 2 PRISMA flowchart for literature search. Fig. 2 Section title: Cooccurrence network Educational score: 4.201011657714844 Domain: biomedical Document type: Study Language: en The exported dataset was utilized to construct a co-occurrence network using VOSviewer software , trend topics and country wise contributions were analyzed using the Biblioshiny Package in R Studio version 2023.06.1. Fig. 3 illustrates a fractionalization network generated using VOSviewer software , where five co-occurrence keywords have been precisely screened and aligned. These keywords represent the most commonly occurring search terms in the research articles analyzed. In this analysis of keyword co-occurrence, a total of four distinct clusters were identified. Varying sizes and colours, highlighting the anecdotal relations, represent the connecting lines between co-occurring keywords and each cluster. Cluster 1 (Red): Bioremediation, sustainable approach employs specific bacterial strains to degrade petroleum hydrocarbons like PAHs found in crude oil. To enhance this process, biosurfactants are produced by these bacteria, which aid in emulsifying the oil, making it more accessible for degradation. Moreover, NPs, such as iron or titanium dioxide (TiO 2 ), can be employed in combination with immobilized microbes, enhancing the efficiency of PAH and crude oil degradation. Cluster 2 (Green) Nano-enhanced biodegradation synergistically employs TiO 2 NPs to catalyze the photocatalytic degradation of PAHs while harnessing bacteria to enhance the degradation of pollutants such as PAHs, crude oil, waste water, and other organic pollutants. Cluster 3 (Blue): Nanomaterials have the potential to substantially alter the bioavailability of organic pollutants like PAHs through enhanced sorption properties, affecting their environmental mobility. Microbes, in turn, play an important role in the biotransformation of these sorbed pollutants, influencing their ultimate fate and environmental impact. Cluster 4 (Yellow): In contaminated or polluted soil, the collaborative act of microbes and NPs such as zero-valent iron initiates the efficient biodegradation of PAHs, offering a sustainable approach to soil remediation. Fig. 3 Keywords co-occurrence network analysis. Fig. 3 Section title: Trend topics and country-wise contributions Educational score: 4.2942609786987305 Domain: biomedical Document type: Study Language: en Nanomaterial-assisted bioremediation of PAHs and other organic pollutants has emerged as a significant trend within the broader scientific landscape. The data reveals that while nanomaterials and bioremediation were trending topics independently and their convergence gained prominent attention from 2019 to 2022 (high frequency) depicted in Fig. 4 a. This synergy offers a promising avenue for addressing the persistent challenge of PAH contamination in the environment. Nanomaterials, including NPs and nanofibers, have shown significant potential for enhancing the performance of bioremediation processes. The porous nanofibers generated through electrospinning cause a substantial surface area that enables the electrostatic attraction of various chemical groups, resulting in the formation of ion exchange membranes. The surface groups of these membranes can be either derived from the polymer or introduced through surface modification. They can be positively, negatively, or both charged . Recent research has been facilitated by advancements in nanotechnology, resulting in the immobilization of microbes or enzymes on electrospun polymeric fibres. PHE, FLT, BAA, and BAP were all removed with efficiencies exceeding 95.1 %, 93.2 %, 79.1 %, and 72.5 % in 6 h, respectively, using laccase carrying electrospun nanofibers. Here, laccase was utilized as the biocatalyst for the degradation of PAHs . By emulsion electrospinning, laccase carrying electrospun fibrous membranes with high laccase catalytic activity and sorption capacity were fabricated, eliminating BAP at 70 % and PHE at 93.8 % from contaminated water. The degradation efficiencies of PAHs by laccase could be noticeably improved by the sorption of PAHs on the laccase-carrying electrospun fibrous membranes, which is higher than free enzyme . These materials can serve as carriers, catalysts, or immobilization matrices for microorganisms, such as Mycobacterium or Arthrobacter , facilitating their action in degrading PAHs. Additionally, discussions on the bioavailability of pollutants, such as PAHs, have been prominent from 2016 to 2022, highlighting the importance of understanding how nanomaterials can improve the accessibility of these compounds to biodegrading microbes. This trend reflects the global growing interest in developing sustainable and effective remediation techniques for PAH contamination. Fig. 4 Bibliometric analysis 4a) Global landscape of nano-bioremediation research on PAHs: Country contributions; 4b) Convergence of nanomaterials and bioremediation trends. Fig. 4 Section title: Trend topics and country-wise contributions Educational score: 2.6092464923858643 Domain: biomedical Document type: Other Language: en Based on the literature search, it was observed that nano-bioremediation of PAHs has gathered significant research attention globally, with China leading to 281 articles . India and the USA also contribute significantly with 149 and 51 articles, respectively, highlighting the extensive work on sustainable remediation approaches. Iran, Korea, and other nations like Brazil, Canada, Malaysia, Pakistan, Saudi Arabia, and Egypt have made notable contributions, collectively emphasizing the worldwide interest in harnessing nanotechnology-based bioremediation for PAH remediation. Section title: Metallic NPs Educational score: 4.130667686462402 Domain: biomedical Document type: Study Language: en Metal NPs, including iron (Fe), silver (Ag), and gold (Au), have received extensive attention in the field of PAH bioremediation due to their considerable surface area and reactivity. These NPs act as carriers for PAH-degrading enzymes or electron mediators, thereby aiding in PAH degradation. Apart from metallic NPs, various other nanomaterials, such as photocatalytic nanomaterials, biopolymers, and CNTs, have also been explored for their potential to address PAH contamination . NPs have proven effective in breaking down PAHs in both water and soil environments. In the study by Al-Zaban et al. study, indigenous fungi, specifically Aspergillus flavus and Trichoderma harzianum , were employed for in situ crude oil bioremediation by employing silver NPs (AgNPs). As much as 57.8 % crude oil degradation was achieved within one week of incubation under optimum conditions at 30 °C, pH 7, 4 g/L of crude oil concentration, 0.05g of AgNPs, and two fungal strains with equal proportion. This demonstrates the potential of low concentrations of NPs in enhancing the biodegradation process, emphasizing the role of nanomaterials in environmental remediation. Section title: Metal oxide NPs Educational score: 4.311574935913086 Domain: biomedical Document type: Study Language: en Metal oxide NPs (e.g. Fe 3 O 4 , ZnO, and TiO 2 ) exhibit potent photocatalytic properties, enabling the degradation of PAHs when exposed to light. These nanomaterials effectively break down PAHs within the aquatic and soil environments . Innovative 3D-printed photocatalyst-polymer composites are also promising for PAH degradation in complex mixtures . The microbial strain B . licheniformis showed its bioremediation efficiency to crude oil especially when combined with biosurfactant and NPs (Zn 5 (OH) 8 Cl 2 at 0.1 g/100 ml concentration or Fe 2 O 3 at 0.2g/100 ml concentration), was 60 % of crude oil . Oyewole et al. observed that Alcaligenes faecalis , in combination with iron oxide NPs and biosurfactants, exhibited increased crude oil biodegradation of up to 84 % of petroleum from contaminated soil. Biosurfactants prevented NPs oxidation and aggregation, enhancing their reactivity for petroleum remediation. According to Parthipan et al. , the iron NPs (Fe 3 O 4 ) were employed to enhance the mineralization process of blend PAHs (PYR, ANT and BAP) by a bacterial consortium composed of Pseudomonas stutzeri and Acinetobacter baumannii . An integrated approach, involving B . subtilis producing biosurfactants, iron NPs, and the bacterial consortium led to an impressive 85 % degradation of mixed PAHs. The inclusion of iron NPs not only enhanced microbial biomass but also facilitated the adsorption of PAHs, ultimately contributing to the proficient removal of these complicated contaminants found in soil and aquatic surroundings. Section title: Carbon-based materials (CBMs) Educational score: 4.628986835479736 Domain: biomedical Document type: Study Language: en CBMs are composed of sp2-hybridized carbon atoms, exhibiting multi-dimensional hybridization. CBMs, such as CNTs, carbon quantum dots (CQDs), carbon black, graphene oxide, and graphene, constitute a versatile class of nanomaterials well-known for their proficiency in PAH adsorption . These nanomaterials could be further improved by incorporating functional groups like carboxyl groups, hydroxyl, and carboxylic acid, thereby imparting hydrophilic properties. This modification enables them to effectively sorb polar compounds with relatively lower molecular weights . CQDs are an advanced carbon nanomaterial that are universally employed in a variety of disciplines due to their exceptional properties. CQDs have been employed to enhance the electronic transmission capabilities of binary semiconductor nanomaterials . Fluorescence, water solubility, biocompatibility, low toxicity, small size and ease of modification, inexpensive scale-up production, and versatile conjugation with other NPs are among the numerous advantageous properties of CQDs . CQDs utilizes selective absorption wavelength for PAHs elimination . Labedella gwakjiensis demonstrated potent PAHs biodegradation capabilities in saline oil-contaminated soils. With the addition of carbon quantum dots iron oxide (CQD.Fe 3 O 4 ) NPs at a concentration of 0.5 g/L significantly enhanced PAHs degradation, particularly PHE, with a degradation rate of 63.63 % and 81.77 % after 48 and 72 h, respectively . The use of graphene-based NPs for PHE extraction has proven to be successful reported by Zhao et al. . Mahpishanian et al. effectively utilized a composite of graphene oxide nanosheets and silica-coated Fe 3 O 4 microparticles, modified with 2-phenylethylamine, for the isolation of a variety of PAHs from aqueous solutions. The hybrid nanostructure formed by gold NPs immobilized in laccase enzyme (laccase-AuNPs@vesicles) achieves a 98.5 % reduction in 4-nitrophenol, surpassing free laccase efficiency by 2.3 times, indicating its superior catalytic performance in environmental remediation . Graphene oxide has proven effective as the substrate for immobilizing bacteria, offering protection in intricate soil environments and enhancing their capabilities in addressing hydrocarbons polluted sites . CNTs, such as single-walled CNTs (SWCNTs) and multiwalled CNTs (MWCNTs) are valued for their chemical stability, thermal resistance, strong adsorption, pH tolerance, and π-π and Van der Waals interactions with PAHs making them excellent adsorbents for contaminant removal . Section title: Magnetic NPs Educational score: 4.176036834716797 Domain: biomedical Document type: Study Language: en A magnetic adsorbent was created by blending Fe 3 O 4 NPs, MWCNTs, and polypyrrole. Interactions between π–π were crucial, facilitated by CNTs and polypyrrole's π bonds. Polypyrrole's –NH 2 groups aided material dispersion in water. Versatile iron and carbon composites are also promising. NPs like ZnFe 2 O 4 were enclosed in a carbon matrix for superparamagnetic C/ZnFe 2 O 4 . The nanocomposite effectively removed NAP and 2-naphthol from water, driven by electrostatic interactions between PAHs and C/ZnFe 2 O 4 for efficient pollutant remediation . Magnetic NPs are a potential agent for environmental remediation facilitated by huge surface area, magnetic receptiveness, and affluence of functionalization . Utilization of magnetic chromium ferrite (CrFe 2 O 4 ) NPs aid in the degradation of ANT, PHE and NAP up to 99 %, 90 %, and 86 % respectively . Section title: Nanocomposites Educational score: 4.3792314529418945 Domain: biomedical Document type: Study Language: en Composites are solid materials with at least one phase <100 nm. Combining metallic NPs and nano supports creates nanocomposites, boosting surface area and adsorption. They protect microorganisms, preventing degradation by toxins, making them ideal for removing pollutants. Magnetic activated carbon nanocomposite from green tea leaf waste effectively removed PAHs, adsorbing them at rates of 28.08, 22.75, 19.14, and 15.86 mg/g for BBF, BAP, CHRY, and BAA respectively . In another study, Mukwevho et al. synthesized a ZnO/Ag/GO nanocomposite, preserving ZnO hexagonal structure. That nanomaterial demonstrated a notable adsorption capacity of 500 mg/g for NAP removal. Through photodegradation, it achieved an 80 % reduction in NAP within 20 min, with further enhancement to 92 % reduction in 50 min. Rani et al. reported that iron oxide based chitosan nanocomposites, specifically ZnFe₂O₄-CS, achieved degradation efficiencies of 95 % for ANT and 92 % for PHE. The NiO–ZnO bimetallic oxide nanocomposites able to degrade 2 ppm of PAHs, achieving 98 % degradation of ANT and 93 % of PHE within 12 h under sunlight exposure . TiO 2 based zinc hexacyanoferrate framework (TiO 2 @ZnHCF) nanocomposite demonstrated superior photocatalytic degradation of PAHs, achieving removal rates of 93%–96 % in water, 82%–86 % in soil, and 81.63%–85.43 % in river sediment . The bacterial consortium of Flavobacterium johnsoniae and Shewanella baltica , immobilized on a goethite-chitosan nanocomposite, achieved a maximum PAHs degradation efficiency of 93.32 % within 3 days . Bioremediation of crude oil in polluted surface water can be effectively achieved using specialized alginate-based nanocomposite beads containing iron oxide NPs immobilized with Bacillus, Pseudomonas , and Klebsiella pneumoniae on biochar, able to degrade 93.7 % of PAHs . This nanocomposite shows promise for efficient PAHs degradation. Section title: Metal-organic frameworks (MOFs) Educational score: 4.480293273925781 Domain: biomedical Document type: Study Language: en MOFs are highly specialized nanomaterials characterized by their unique porous and crystalline structure, created through the coordination of metal ions or clusters with organic ligands. MOFs are renowned for their exceptional surface area and customizable porosity, reusability, and versatile design options, making them invaluable for gas storage, separation, catalysis, and drug delivery applications. These materials offer a precisely engineered structure, allowing them to be tailored for specific uses. MOFs, along with other advanced nanosorbents like nano-polymers, represent the forefront of petroleum wastewater treatment, showcasing their potential in the efficient removal of pollutants like PAHs . Using bimetallic metal-organic frameworks with 1,4-benzenedicarboxylic acid activated through peroxymonosulfate, 99 % of PHE removal efficiency was reported at pH 3.15, 1.0 mg/L PHE, and a reaction time of 30 min . While MOFs offer benefits like low energy consumption and high efficiency, it often suffers from instability in aqueous environments, leading to phase changes, loss of crystallinity, and structural decomposition. Research suggests that incorporating secondary metal nodes can enhance both catalytic activity and stability, resulting in bimetallic MOFs. Peroxymonosulfate activated molecularly imprinted bimetallic MOFs (Al/Co-MOFs@MIP) effectively target the removal of PAHs from soil washing effluents, resulting in 94 % PHE degradation in 1 h 30 min . The study found that using nanomaterials like zeolite imidazolate framework-8 (ZIF-8) and combining it with citric acid (CA) greatly improved the removal of PHE by B . subtilis . The integration of ZIF-8 and CA significantly improved the growth and cell viability of Bacillus subtilis ZL09–26, while also reducing the toxic effects of PHE stress. Acting as an anionic surfactant, CA modified the surface charge of ZIF-8, facilitating the formation of a biomimetic mineralized protective shell around the bacteria. This ZIF-8-CA coating, characterized by surface roughening and particle aggregation, effectively encapsulated the bacteria, enhancing their ability to degrade PAHs. Compared to the control condition ( Bacillus subtilis ZL09–26 alone), these nano-modified conditions showed significant increases in PHE removal rates. Particularly, Bacillus subtilis ZL09–26@ZIF-8-CA was highly influential, removing 94.14 % of PHE in just 6 days. These highlights are the vital character of the nanomaterials in enhancing PAHs cleanup when combined with bacteria . Section title: Nanomaterial attributes facilitating PAH removal Educational score: 3.952481508255005 Domain: biomedical Document type: Study Language: en Recently, as an emerging technology, interest growing in utilizing nanomaterial-based tools for practical solutions for the remediation of various pollutants in contaminated sites. In this regard, a wide array of nanomaterials has been introduced into the market as nanosorbents, offering enhanced capabilities for treating water contaminated with PAHs, ultimately making it suitable for reclaim . Nanomaterials possess structural elements with dimensions ranging from 1 to 100 nm (nm) in at least one dimension. These materials stand out due to their unique characteristics, notably a significantly increased surface-to-volume ratio as well as enhanced magnetic and catalytic traits when compared to their bulk materials . Section title: Nanomaterial attributes facilitating PAH removal Educational score: 4.838578224182129 Domain: biomedical Document type: Study Language: en Nanomaterials are characterized by their diminutive dimension, which enables them to have a greater surface-to-volume ratio. This attribute allows them to engage in more significant interactions with the molecules in their environment. As the dimension decreases, the concentration of ions on the surface increases, thereby increasing their reactivity. Nanomaterials possess distinctive characteristics that render them highly desirable in various applications, such as catalysis and sensing . In many cases, nanomaterials exhibit distinctive magnetic properties. By treating hydrocarbon-degrading microbial cells like Alcanivorax borkumensis having a positively charged polymer i.e., polyallylamine hydrochloride and layered magnetic nanomaterials, a protective shell of about 70–100 nm was formed on the cell wall. Polycation coated magnetic NPs utilize the direct deposition of positively charged iron oxide NPs onto microbial cells during brief incubation in high NP concentrations. Gram-negative bacteria have cell walls with a thin peptidoglycan layer between the outer membrane and inner plasma membrane. The presence of lipopolysaccharides gives the cell walls a negative charge, attracting cationic particles through electrostatic interactions. These intact cells exhibit a negative potential of −16 mV, facilitating the rapid deposition of cationic magnetic complexes on the bacterial cell walls. A cationic charge of polyallylamine and 20 nm iron oxide NPs enables a swift, single-step encapsulation process by exploiting electrostatic interactions with bacterial surfaces. The cationic polycation-coated magnetic NPs act as electron donors, while the negatively charged bacterial cell walls serve as electron acceptors. This electrostatic interaction facilitates the rapid deposition of cationic magnetic complexes on the bacterial surfaces, forming a charge transfer complex . This innovative approach enhances the efficacy and endurance of cells in the degradation of hydrocarbons. The extensive surface area of nanomaterials leads to a highly active reaction environment, which in turn enhances their catalytic efficacy. Quantum size effects at the nanoscale enhance the efficacy of catalytic processes by modifying electronic structures. Nano-catalysts enhance reaction selectivity at lower temperatures, reduce side reactions, promote recycling, and reduce environmental and health risks. These advances in catalytic nanotechnology promote greener and more sustainable processes by replacing low-quality materials with NPs . Immobilized microbial cells not only improve process stability and catalytic efficiency but also simplify the cell recovery for subsequent reuse. Enzymes can be fixed onto NPs via methods such as adsorption, entrapment, covalent bonding, or membrane confinement. Immobilized enzymes exhibited approximately a twofold increase in catalytic activity compared to their native counterparts, primarily due to heightened surface hydrophobic nature. Their stability depends on the number of bonds formed between the NPs and enzymes . Acevedo et al. harnessed manganese peroxidase (MnP) from the chilean white-rot fungus Anthracophyllum discolor , immobilizing it onto nano clay (100 nm) derived from volcanic soil. Interestingly, physical adsorption process successfully immobilized 75 % of the enzyme. The immobilized MnP demonstrated superior PAH degradation, particularly with PYR (>86 %) and ANT (>65 %) individually. It also exhibited some capacity to degrade FLT (<15.2 %) and PHE (<8.6 %). Section title: Nanomaterial attributes facilitating PAH removal Educational score: 4.143834114074707 Domain: biomedical Document type: Study Language: en Nanomaterials possess remarkable mechanical properties, including high strength and flexibility. This is attributed to an increased density of defects and interfaces in nanoscale structures. CNTs and graphene are especially well-known for their exceptional mechanical strength, with applications in nanocomposites [ , , ]. Combining crude enzymes from Trametes maxima and Paecelomices carneous within alginate beads and trimetallic TiO 2 –C–Ag NPs enhances their mechanical stability and resistance to protease attack. This hybrid nanomaterial exhibits increased PHE removal capacity, achieving 94.3 % removal in continuous mode . Nanomaterials possess distinct electrical conductivity properties due to their size and unique characteristics, differing from macroscopic materials. However, they generally exhibit lower thermal and electrical conductivity than bulk materials. Section title: Bioremediation and nano-bioremediation for PAHs degradation in liquid and soil samples Educational score: 4.199358940124512 Domain: biomedical Document type: Study Language: en Table 1 , Table 2 provide a comparative analysis of nano-bioremediation and bioremediation for PAHs remediation under the same experimental design, specific to liquid and soil samples, respectively. The compilation of data extracted from 26 current research papers focusing on the assessment of bioremediation rates, initial and final concentrations of PAHs, as well as nano-bioremediation rates, type of nanomaterial used initial and final concentrations, and various other parameters ( Tables S1 and S2 ). Zhoa et al. reported that reduced graphene oxide demonstrated a 99 % degradation of NAP in nano-bioremediation with Burkholderia cepacia, compared to 67.3 % with bioremediation alone. Therefore, addition of nanomaterial in bioremediation increased the PAHs remediation. The degradation condition for ANT was achieved using titanium dioxide NPs with Alcaligenes faecalis in a nano-bioremediation approach, resulting in a 37.9 % degradation, compared to 24.2 % with Alcaligenes faecalis . In bioremediation (phytoremediation) without NPs, Proteobacteria, Actinobacteria, Bacteroidota, and Firmicutes achieved a 55.5 % degradation of BBF. Using graphene oxide in a nano-bioremediation approach with the same microbial consortia, the degradation of BBF increased to 74.22 % . Chai et al. reported that bioremediation using lignin peroxidase (LiP)-extracted from Pichia methanolica targeting PHE achieved 23.7 % efficiency, whereas nano-bioremediation with chitosan-modified halloysite nanotubes and Pichia methanolica (LiP) targeting PHE achieved approximately double the removal efficiency at 51.3 %. Table 1 Bioremediation and Nano-Bioremediation for PAHs Degradation in Liquid samples. Table 1 Remediation method Type of NP Bioagent PAHs type Size of NP (nm) Shape of NP PAHs degradation (%) References Bioremediation Without NP Labedella gwakjiensis PHE NA NA 37.12 Nano-Bioremediation Carbon Quantum Dots conjugated with Iron (III) Oxide Labedella gwakjiensis PHE 10 Spherical 81.77 Bioremediation Without NP Alcaligenes faecalis ANT NA NA 10.4 Nano-Bioremediation Titanium Dioxide NPs Alcaligenes faecalis ANT 17.11 Spherical and granular 21.3 Bioremediation Without NP Achromobacter sp. PHE NA NA 56.24 Nano-Bioremediation Titanium Dioxide with biochar Achromobacter sp. PHE 276.1 Stacked graphite sheet structure and rectangular shaped 72.58 Bioremediation Without NP Burkholderia cepacia NAP NA NA 67.3 Nano-Bioremediation Reduced graphene oxide Burkholderia cepacia NAP NM NM 99.0 Bioremediation Without NP Pseudomonas sp. Rhodocucus sp. ANT NA NA 58.3 Nano-Bioremediation Polyimide aerogels Pseudomonas sp. Rhodocucus sp. ANT NM NM 78.6 Bioremediation Without NP Pseudomonas stutzeri and Acinetobacter baumannii ANT, PYR, BAP NA NA 52.6 Nano-Bioremediation Iron nanoparticles Pseudomonas stutzeri and Acinetobacter baumannii ANT, PYR, BAP 134 Spherical 65.7 Nano-Bioremediation Iron nanoparticles Biosurfactant ( Bacillus subtilis ) Pseudomonas stutzeri and Acinetobacter baumannii ANT, PYR, BAP 134 Spherical 85 Bioremediation Without NP Penicillium oxalicum PYR NA NA 72 Nano-Bioremediation Carbon nanotube composites Penicillium oxalicum PYR NM NM 90 Bioremediation Without NP Biofilm from consortia Planococcaceae, Oxalobacteraceae etc PHE NA NA 12.97 ± 0.44 Nano-Bioremediation Copper and Nitrogen co-doped Titanium Dioxide Biofilm from consortia Planococcaceae, Oxalobacteraceae etc PHE 10–30 NM 88.63 Bioremediation Without NP Biofilm from consortia Planococcaceae, Oxalobacteraceae etc PYR NA NA 6.65 Nano-Bioremediation Copper and Nitrogen co-doped Titanium Dioxide Biofilm from consortia Planococcaceae, Oxalobacteraceae etc PYR 10–30 NM 63.89 Bioremediation Without NP Candida tropicalis ICP NA NA 61 Nano-Bioremediation Iron nanoparticles Candida tropicalis ICP 50 Spherical 75 Bioremediation Without NP Rhodotorula sp. Debaryomyces hansenii and Hanseniaspora valbyensis BghiP NA NA 60.0 Nano-Bioremediation Zinc Oxide Rhodotorula sp. Debaryomyces hansenii and Hanseniaspora valbyensis BghiP 10 Rod 60.7 Bioremediation Without NP Rhodotorula sp. Hanseniaspora opuntiae and Debaryomyces hansenii BAP NA NA 76.0 Nano-Bioremediation Zinc Oxide Rhodotorula sp. Hanseniaspora opuntiae and Debaryomyces hansenii BAP 50 Spherical 77.2 Bioremediation Without NP Bacillus thuringiensis PHE NA NA 65.71 Nano-Bioremediation Multi-Walled Carbon Nanotube Buckypaper Bacillus thuringiensis PHE 200 Spherical 93.81 Bioremediation Without NP Sphingomonas sp. PHE NA NA 74.6 Nano-Bioremediation Nano bamboo charcoal Sphingomonas sp. PHE NM NM 93.01 Bioremediation Without NP Paracoccus sp. BAP NA NA 60 Nano-Bioremediation Hematite NPs Paracoccus sp. BAP NM NM 45.8 Bioremediation Without NP Sphingomonas sp. PHE NA NA 69.83 Nano-Bioremediation Nano bamboo charcoal Sphingomonas sp. PHE 401.9 Irregular 94 Bioremediation Without NP Methanosarcina and Methanosaeta, Pseudomonas, Cloastridia, and Synergistetes PYR NA NA 40.8 Nano-Bioremediation Iron (II) Sulfide Methanosarcina and Methanosaeta, Pseudomonas, Cloastridia, and Synergistetes PYR 20–50 NM 77.5 Nano-Bioremediation Magnetic carbon Methanosarcina and Methanosaeta, Pseudomonas, Cloastridia, and Synergistetes PYR 20–50 NM 72.1 Bioremediation Without NP Archaea and methanogen PHE NA NA 60.52 Nano-Bioremediation Magnetite powder Archaea and methanogen PHE 50–100 Spherical 70.94 Nano-Bioremediation Nanoscale Iron (III) Oxide Archaea and methanogen PHE 50–100 Spherical 70.89 NA=Not Applicable, NM=Not Mentioned. Table 2 Bioremediation and Nano-Bioremediation for PAHs Degradation in soil sample. Table 2 Remediation method Type of NPs Bioagent PAHs type Size of NPs (nm) Shape of NPs PAHs degradation (%) References Bioremediation Without NP Alcaligenes faecalis ANT NA NA 24.2 Nano-Bioremediation Titanium Dioxide NPs Alcaligenes faecalis ANT 17.11 Spherical and granular 37.9 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) FLT NA NA 92.60 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) FLT NM NM 95.57 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) PYR NA NA 90.11 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) PYR NM NM 95.88 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BAA NA NA 87.70 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BAA NM NM 93.30 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) CHRY NA NA 88.85 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) CHRY NM NM 91.82 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BBF NA NA 55.50 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BBF NM NM 74.22 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BKF NA NA 55.97 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BKF NM NM 62.00 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BAP NA NA 56.15 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) BAP NM NM 67.37 Bioremediation (phytoremediation) Without NP Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) DBA NA NA 58.03 Nano-Bioremediation Graphene oxide Proteobacteria, Actinobacteria, Bacteroidota,Firmicutes etc and Fire Phoenix (Plant Species) DBA NM NM 67.75 Bioremediation Without NP Proteobacteria, Acidobacteria, Gemmatimonadota, Bacteroidota (Soil microbes) PAHs NA NA 19.57 Nano-Bioremediation Graphene oxide Proteobacteria, Acidobacteria, Gemmatimonadota, Bacteroidota (Soil microbes) PAHs NM Irregular 41.07 Bioremediation Without NP Geobacter and Geothrix PAHs NA NA 8.7 Nano-Bioremediation Magnetite NPs Geobacter and Geothrix PAHs 100 Spherical 86 Bioremediation Without NP Pichia methanolica (LiP) PHE NA NA 23.7 Nano-Bioremediation Chitosan-modified halloysite nanotubes Pichia methanolica (LiP) PHE NM Rod 51.3 Bioremediation Without NP Pichia methanolica (LiP) FLU NA NA 25 Nano-Bioremediation Chitosan-modified halloysite nanotubes Pichia methanolica (LiP) FLU NM Rod 38.1 Bioremediation Without NP Soil Microbes NAP NA NA 92.7 Nano-Bioremediation Silver Phosphate on Iron (III) Oxide NP Soil Microbes NAP 20–40 Irregular 93.7 Bioremediation Without NP Soil Microbes ANT NA NA 84.8 Nano-Bioremediation Silver Phosphate on Iron (III) Oxide NP Soil Microbes ANT 20–40 Irregular 91.9 Bioremediation Without NP Soil Microbes PHE NA NA 86 Nano-Bioremediation Silver Phosphate on Iron (III) Oxide NP Soil Microbes PHE 20–40 Irregular 94.6 Bioremediation Without NP Soil Microbes FLU NA NA 68.6 Nano-Bioremediation Silver Phosphate on Iron (III) Oxide NP Soil Microbes FLU 20–40 Irregular 82.3 Bioremediation Without NP Soil Microbes PYR NA NA 63.4 Nano-Bioremediation Silver Phosphate on Iron (III) Oxide NP Soil Microbes PYR 20–40 Irregular 78.8 Bioremediation Without NP Paracoccus aminovorans + Soil microbes PAHs NA NA 46.9 Nano-Bioremediation Graphene oxide Paracoccus aminovorans + Soil microbes PAHs 17.92 Irregular 62.86 Bioremediation Without NP Bacillus cereus, Acidovorax wohlfahrtii, and Bacillus thuringiensis PYR NA NA 88 Nano-Bioremediation Hematite NPs Bacillus cereus, Acidovorax wohlfahrtii, and Bacillus thuringiensis PYR 28–55 Spherical 96 NA=Not Applicable, NM=Not Mentioned. Section title: Correlation matrix Educational score: 4.161680221557617 Domain: biomedical Document type: Study Language: en Fig. 5 a and b shows that the degradation of PAHs effectively lowers their final concentration, since there is a negative link between degradation and concentration in both soil and liquid samples as per different studies cited in Supplementary Tables S1 and S2 . A moderate positive association was seen between the presence of bioagents and the degradation of PAHs in both the soil and liquid samples, suggesting that specific bioagents can accelerate degradation in these settings. In contrast, soil samples show a moderate positive correlation with duration and a negative correlation with pH, indicating that higher duration may extend the degradation process and lower pH levels, respectively. Nevertheless, there is a strong negative correlation of temperature, showing that higher temperatures considerably shorten the degradation duration. Liquid samples reveal that the type of NPs affirms a stronger positive correlation with PAHs degradation and bioagent, indicating that NPs play a substantial role in both liquid and soil medium for improving degradation and interacting with bioagents. Temperature significantly influences PAH breakdown in soil samples, time and bioagents exert a minor influence whereas the effects of pH and NP type are minimal. Temperature impacts duration and pH in liquid samples, while bioagents are more important in solid samples. When compared to soil samples, NP type has a more significant impact on bioagent interaction and degradation. Fig. 5 Correlation matrix heatmap for A) Liquid samples B) Soil samples. Fig. 5 Section title: Size and shape of NPs Educational score: 4.0680460929870605 Domain: biomedical Document type: Review Language: en The small size of nanomaterials provides with high surface area and are strongly adsorbed on the surfaces of microbial cells. Additionally, electrostatic interactions are a crucial factor of the interacting force between cells and NPs . The desirable modifications in size and shape of nanomaterials improve its functioning, which may offer important advantage for elimination of contaminants . On reviewing, it was generally found that the most frequent sizes of NPs were 40 nm and 50 nm. No studies utilized particles smaller than 10 nm due to their ability to penetrate inside cells, although some involving complex structures exhibited a wider range of nano-sizes. As per the literature, most common shape for nanomaterial was spherical. Spherical shapes often enhance mobility and stability, while irregular shapes may offer more active sites for adsorption. Spherical nanomaterials tend to aggregate less, enhancing their effectiveness in nano-bioremediation. Different shapes of nanomaterials affect their surface area, reactivity, and interaction with contaminants and microorganisms in bioremediation . Section title: Size and shape of NPs Educational score: 4.154444694519043 Domain: biomedical Document type: Study Language: en Biosynthesized palladium NPs, due to their smaller size and higher surface-to-volume ratio, validated superior catalytic performance compared to chemically reduced palladium . Its small size allows it to penetrate deep into polluted regions that microbes cannot reach, thereby extending the applications of nano-bioremediation. Therefore, it is crucial to understand the interactions between NPs and microbes. However, the small size of NPs presents both advantages and limitations. Less soluble NPs, such as gold, platinum, and silver, are generally less toxic compared to others. NPs sized 1–12 nm can enter microbial cells, stimulating the production of reactive oxygen species and thereby reducing microbial growth . El Bestawy et al. found that NPs (10–20 nm) penetrated cells causing cell destruction when incubated for 6 h. To prevent the toxicity, the experiment runs for 4 h creating effective Fe₃O₄-immobilized bacterial cultures capable of degrading total petroleum hydrocarbons by 85 %. Therefore, research should be focused on optimizing methods to avoid NPs toxicity in soil and water, understanding their interactions with biotic and abiotic agents. Section title: Bioremediation versus nano-bioremediation Educational score: 4.108007907867432 Domain: biomedical Document type: Study Language: en The compilation of collected secondary data, irrespective of types of PAHs, microbial strains, nanomaterial types, concentrations, and other experimental setups, yielded a generalized outcome, and its graphical representation is illustrated in Fig. 6 . It was observed that, when compared, traditional bioremediation achieved an average removal efficiency of 52.2 %, while nano-bioremediation exhibited a higher average removal efficiency of 71.1 %. The application of NPs in bioremediation greatly enhanced the efficiency of remediation, resulting in an 18.9 % increase in the elimination of PAHs in liquid samples. Soil sample analysis consistently revealed that traditional bioremediation attained an average removal efficiency of 60.8 %. However, when nano-bioremediation is included, there is a significant increase of 14.3 %, resulting in an average removal efficiency of 75.1 %. The pattern emphasised the exceptional hybrid capabilities of nano-bioremediation in effectively eliminating PAHs from the environment. Fig. 6 Different attributes of nano-bioremediation facilitating PAHs breakdown. Fig. 6 Section title: Nanomaterial-aided microbial PAH degradation strategies Educational score: 4.180834770202637 Domain: biomedical Document type: Review Language: en Nano-bioremediation technology offers a potential remedial approach for PAH in contaminated soil, contributing to environmental welfare. Its application enhances water and soil quality, nurturing agricultural productivity, vegetation growth, and microbial survival . An additional advantage is its ability to prevent hazardous compounds from leaching into groundwater . The interaction between NPs functional surfaces and biological interfaces enhances environmental restoration. Emerging NPs types and concentrations provide a solution for recalcitrant PAH biodegradation . Previous research highlights specific roles of NPs in enhancing biodegradation rates. For a decade, environmental specialists have focused on remediating PAHs at contaminated sites, facing multifaceted challenges such as soil properties, secondary pollution, treatment duration, and budget constraints. Physicochemical and biological remediation methods, like incineration, electrokinetic, soil washing, and phytoremediation, have been explored . Physicochemical approaches involve limitations such as high costs and monitoring complications . In contrast, integrating nanotechnology and biological methods offers an environmentally friendly approach to addressing the environmental impact of PAHs contamination. Section title: Nanomaterial-aided microbial PAH degradation strategies Educational score: 4.198467254638672 Domain: biomedical Document type: Review Language: en The interaction between microbes and NPs in the adsorption of PAHs is complicated, mainly attributed to the complex molecular structures of PAHs. Mechanistic insights into this interaction remain limited, and studies assuming these mechanisms are not yet fully elucidated. Numerous research endeavors have attempted to elucidate the potential degradation strategies of PAHs, which exhibit variation across microbial strains and NP characteristics . The review explores various strategies for nano-bioremediation aimed at the breakdown of PAHs. Fig. 7 illustrates the key mechanisms of nano-bioremediation strategies for PAH degradation. Nanoparticle-mediated electron transfer demonstrates the transfer of electrons from NP to microbes, initiating reactions that lead to the degradation of PAHs. Enzyme-immobilized NP, where microbes secrete enzymes that are immobilized onto NPs through linkers, enabling effective interactions for PAH breakdown. NP enhances microbial activity by promoting enhanced cell metabolism and new metabolic pathways that contribute to the degradation of PAHs. The microbial cell immobilized NPs, employ techniques such as cross-linking, entrapment, and encapsulation for efficient immobilization and targeted PAH biodegradation. Lastly, integrated nano-bioremediation is mentioned, emphasizing the combined action of nanomaterials and biodegradation pathways for comprehensive PAH remediation. Fig. 7 Nano-bioremediation strategies for enhanced PAH degradation. Fig. 7 Section title: Microbial cell immobilized NPs Educational score: 4.3989644050598145 Domain: biomedical Document type: Study Language: en NPs offer an advanced means of immobilizing microbial cells or consortia for targeted chemical degradation or reclamation . Immobilization confines microbial cells or enzymes within a solid space, preserving their catalytic activity for reuse. Techniques include cross-linkage, encapsulation, adsorption, and entrapment. Surface-confined microbes exhibit resistance to harsh conditions, enhanced stability, greater biomass, and improved contaminant degradation potential . In contrast to conventional methods involving micron-sized media or fixed surfaces, magnetic NPs like Fe 3 O 4 , functionalized with ammonium oleate, have been applied to coat P . delafieldi . Employing an external magnetic field, these coated microbial cells gather at specific reactor wall sites, separate from the surrounding solution, and can be reused for treating the same substrate. This approach not only enhances microbial activity and strength but also facilitates their recyclability and recovery, maintenance them against adverse environmental conditions . This process presents a comprehensive strategy, ensuring prolonged and effective biodegradation while enhancing cellular resilience to harsh environmental challenges . This strategy influences the immobilization of microbial cells through NPs, presenting the remarkable synergy between nanotechnology and bioremediation for sustainable developmental solutions. Section title: Microbial cell immobilized NPs Educational score: 4.120573997497559 Domain: biomedical Document type: Study Language: en Biofunctionalized NPs are created by incorporating microbes, enzymes, or biostabilizers onto their surfaces, enhancing their affinity for PAHs. The process entails the initial adsorption of PAHs onto the NPs surface, followed by π–π interactions that drive degradation. After successful degradation, these NPs can be efficiently recycled for additional rounds of PAHs remediation, illustrated in Fig. 8 . An exogenous bacterial consortium ( Enterobacter cloacae and P . otitidis ) immobilized with Fe 3 O 4 NPs achieved prominent oil degradation efficiencies, with the highest removal rates of total petroleum hydrocarbons, and grease recorded at 85 %, and 83.9 %, respectively, within just 4 h . Fig. 8 Mechanisms of biofunctionalized nanoparticles in enhancing PAHs degradation. Fig. 8 Section title: Microbial enzyme-immobilized NPs Educational score: 4.340700149536133 Domain: biomedical Document type: Study Language: en One potential mechanism involves the secretion of specialized enzymes by bacteria, which become immobilized on NPs, facilitating the adsorption of PAHs and subsequently mediating their degradation. Alternatively, bacteria may efficiently degrade PAHs extracellularly, but its efficiency can be upregulated by applying NPs. The nature and strength of interactions between microorganisms and NPs are likely crucial factors influencing the enhanced biodegradation of PAHs . Enzymes functioning as biocatalysts in bioremediation are highly specific and effective, but their practical utility is hindered by instability and short lifetimes . Oxidation reduces enzyme stability and efficiency, limiting their application as cost-effective alternatives to synthetic catalysts. NPs offer a solution to address this by magnifying enzyme stability, longevity, and reusability. Binding enzymes to these magnetic NPs enable easy separation using a magnetic field, significantly prolonging their activity from hours to weeks . The study employs trypsin, peroxides, and catabolic enzymes uniformly coated onto core-shell magnetic NPs, demonstrating a remarkable increase in enzyme lifetime and activity. These nanoparticle-enzyme conjugates prove to be more stable, efficient, and cost-effective, shielding enzymes from oxidation. The magnetization of these NPs allows efficient magnetic separation, further enhancing enzyme productivity . Section title: Microbial enzyme-immobilized NPs Educational score: 4.1235761642456055 Domain: biomedical Document type: Study Language: en In a recent study, Deng et al. investigated the potential of immobilized laccase from T . versicolor for efficient degradation of PAHs. When immobilized on Fe 3 O 4 –SiO 2 -chitosan, the laccase demonstrates distinguished operational stability and reusability, with a capacity of 158 mg/g. Within 48 h, remarkable degradation efficiencies of 81.9 % for ANT and 69.2 % for BAP are achieved. Quantum calculations and mass spectrum analyses reveal anthraquinone and BAP-dione as degradation products. This recoverable magnetic immobilized laccase indicates significant promise for PAH remediation, emphasizing its potential application in environmental restoration. Section title: Integrated nano-biodegradation Educational score: 4.5222930908203125 Domain: biomedical Document type: Study Language: en Bioremediation has limitations due to its time-dependence, high cost, and low bioavailability, especially in highly contaminated environments with HMW-PAHs. To overcome these challenges, integrated approaches like physical-chemical or physical-biological methods may be employed, combining techniques such as solvent extraction, chemical oxidation, and bioremediation for more effective remediation . Recent advancements in nanotechnology have significantly enhanced integrated remediation approaches by leveraging nano-sized materials to modify the physicochemical properties of contaminants. This technology synergizes with chemical methods like surfactant addition, to increase bioavailability and biological methods, such as biodegradation. However, cautious attention is essential, including choosing non-toxic nanomaterial biomolecules for functionalization and avoiding toxic reducing agents in nanomaterial synthesis. To address this, adopting green and biologically synthesized NPs emerges as a promising solution to mitigate environmental impact . However, biosurfactant-producing bacteria such as B. subtilis and iron NPs address the proficient degradation of hazardous PAHs. Biosurfactant enhances PAH bioavailability, aiding bacterial settlement, while iron NPs promote biomass growth and PAH adsorption. This integrated approach achieved an 85 % degradation efficiency for mixed PAHs (ANT, PYR, and BAP) in versatile ecosystems. This strategy highlights the efficient and comprehensive PAH pollutant removal . Section title: NPs enhanced microbial activity Educational score: 4.395160675048828 Domain: biomedical Document type: Study Language: en NPs have demonstrated the ability to boost microbial activity during the biodegradation of PAHs by creating a conducive microenvironment for microorganisms. Notably, magnetic iron NPs have been observed to enhance cell adhesion, increase nutrient availability, and facilitate metabolic processes, thereby significantly expediting PAH degradation . Bioaugmentation with graphene oxide-immobilized bacterial pellets (GOBP) enhances PAHs degradation in contaminated soil. High-efficiency degrading bacteria Paracoccus aminovorans embedded in GO-alginate-Luria-Bertani composites show 18.51 % higher removal of PAHs (62.86 % over 35 days) than traditional pellets. GOBP focuses on high-molecular-weight PAHs while increasing the abundance of embedded bacteria and enriching potential indigenous degraders like Pseudarthrobacter and Arthrobacter . This innovative approach offers an advanced technique for remediating organic pollutants in challenging soil environments using bioaugmentation . GO promotes microbial degradation of PAHs, stimulating bacterial growth and gene expression participating in microbial mobility (flagellar assembly), microbial chemotaxis, the two-component system, and phosphotransferase system in soil. In short-term exposure, GO enhances the abundance of degrading microbes, accelerating PAH breakdown. However, extended exposure may lead to degradation saturation. This study indicates GO's impact on microbial PAHs degradation, providing insights into effective environmental remediation and emphasizing the importance of microbial movement and related genetic processes . Section title: Nanoparticle-mediated electron transfer Educational score: 4.593306064605713 Domain: biomedical Document type: Study Language: en Nano-bioremediation of PAHs employs NPs and zero-valent iron (nZVI) to enhance electron transfer, a crucial step in the degradation process . Electron transfer intensifies the transformation of recalcitrant PAHs into simple and less hazardous intermediates through breaking down complex molecules into simpler. Microbial fuel cells (MFCs) offer a sustainable approach to electricity generation and organic contaminant removal. Carbon nanomaterials, including graphene, reduced graphene oxide, and CNTs, enhance MFC performance due to their increased surface area, conductivity, and electrochemical capacity . In a sediment MFC study, reduced graphene oxide -modified anodes exhibited the highest voltage output (30.60–48.61 mV) and PHE removal rates up to 71.2 %. PHE degradation correlated positively with Pseudomonas, Thauera, Diaphorobacter, Tumebacillus, and Lysobacter abundances, while PYR degradation correlated with loss on ignition (LOI) degradation. Carbon nanomaterial-modified MFCs show the ability for efficient electricity generation and organic pollutant removal . Lv et al. found enhanced anaerobic-aerobic treatment with nZVI supplemented with rhamnolipid (biosurfactant) and anthraquinone-2,6-disulfonic acid (AQDS) achieved significant degradation rates of 72.81 % for total PAHs and 79.47 % for HMW-PAHs. Key PAHs-degrading bacteria, including Clostridium , Geobacter , and Rhodococcus were dominant contributors. The breakdown route of PAHs, which involves both aerobic and anaerobic processes, was identified by the study of metabolic enzyme function, where nZVI oxidation under anaerobic conditions released effective electron donors for microbial degradation and nZVI-microorganism interactions aided soil pollutant removal. Utilized as an electron shuttle, AQDS facilitates extracellular electron transfer, expediting the exchange between anaerobic bacteria and nZVI. This process enhances system reduction and boosts the microbial transformation rate of soil PAHs . While nZVI is a player, other NPs like Nano-MoO 2 also activate peroxymonosulfate for PAH derivative degradation . Continuous research aims to refine nano-bioremediation strategies, exploring novel techniques and NPs to achieve more effective PAH degradation. Section title: Biogenic nanomaterial-mediated PAHs degradation Educational score: 4.613788604736328 Domain: biomedical Document type: Study Language: en Biogenic nanomaterials, such as those synthesized using microorganisms and plant extracts, have gained significant attention in the field of green nanotechnology for the remediation of PAHs. These environmentally friendly nanomaterials offer a promising alternative to outdated chemical techniques. In contrast to the time-consuming and challenging top-down approaches, biogenic NPs are bottom-up products formed through biological reduction processes. Microbial enzymes and plant phytochemicals act as efficient reducing agents, facilitating the degradation of PAH contaminants in various environmental matrices. This approach aligns with the principles of green chemistry, emphasizing safety and sustainability [ , , ]. Bacterial biogenic nanomaterials have emerged as a potent and eco-green solution for addressing the degradation of PAHs. These nanomaterials are synthesized using various bacterial strains and metabolites, making them environmentally sustainable reducing agents. Biogenic NPs are formed through the addition of a metal precursor to bacterial or plant metabolites, followed by the introduction of ligands or biostabilizers to functionalize the NPs. These functionalized NPs adsorb photons, initiating the degradation of PAHs into harmless metabolites, constituting an environmentally friendly degradation process . For instance, A . extremophiles have been employed for the synthesis of crystalline zirconium dioxide (ZrO 2 ), where metabolites discharged into the growth medium efficiently reduced ZrOCl 2 to ZrO 2 . Lactobacillus bacterial strains have been utilized to synthesize titanium dioxide (TiO 2 ) NPs , while a thermophilic bacterium, Geobacillus stearothermophilus , played a pivotal role in the biogenic synthesis of silver (Ag) and gold (Au) NPs . These bacterial strains and their metabolites have been suitable for reducing metal compounds into NPs, facilitating the green remediation of PAH contaminants . B . subtilis , found in rhizosphere soil, exhibited the ability to biosynthesize iron oxide NPs . Moreover, various other bacterial species have demonstrated their capacity to serve as biofactories for synthesizing diverse NPs, including gold, silver, copper, iron, and more. Fig. 9 Eco-sustainable degradation of PAHs using biogenic nanomaterials: Synthesis and mechanism. Fig. 9 Section title: Biogenic nanomaterial-mediated PAHs degradation Educational score: 4.3163299560546875 Domain: biomedical Document type: Study Language: en Fungi have emerged as eco-friendly and economically viable candidates for NPs synthesis due to their unique attributes . Ganesan et al. utilized the endophytic fungus Periconium sp. for ZnO NPs synthesis, while Clarance et al. employed Fusarium solani for gold NPs production, with key roles played by secreted polypeptides and proteins. Kobashigawa et al. demonstrated the bio-reduction of AgNPs using the ligninolytic fungus Trametes trogii , while Gudikandula et al. employed white-rot fungi for AgNP synthesis. A . oryzae facilitated SeNP reduction from fermented lupin extract . Vago et al. harnessed Aspergillus, Penicillium, and Trichoderma fungi for AuNP reduction. Fungi offer high bioaccumulation capacity, metal resistance, ease of handling, and enzymatic capabilities, making them promising for NPs production. Chakravarty et al. investigated the biodegradation potential of ANT was investigated using a novel approach involving green-synthesized TiO 2 NPs derived from Paenibacillus sp. and Cyperus brevifolius , known for their PAHs remediation abilities, in conjunction with the bacterium A . faecalis , isolated from crude oil-contaminated soil. The combined application of TiO 2 NPs and A . faecalis led to a considerable reduction in ANT concentration, achieving a 21.3 % decrease in liquid culture after 7 days and a remarkable 37.9 % reduction in soil microcosms over 30 days. GC-MS analysis identified five metabolites, including 1,2-anthracenedihydrodiol, 6,7-benzocoumarin, 3-hydroxy-2-naphthoic acid, salicylic acid, and 9,10-anthraquinone, elucidating a novel ANT biodegradation pathway. These examples illustrate the potential of bacterial biogenic nanomaterials in the sustainable remediation of PAH pollutants, offering a promising avenue for eco-sustainable approaches to tackle this environmental challenge. Section title: Discussion Educational score: 4.186126708984375 Domain: biomedical Document type: Review Language: en This review highlights the role of nanomaterials in bioremediation to remediate PAHs in both liquid and soil samples. It compiles recent research leading to the interpretation of significant advancements in applying both nanomaterials and bioagents for PAH remediation. Bibliographical analysis indicates a growing trend in this research area, though limited studies exist. This review also spotlights the potential and need for further exploration in this field. Elumalai et al. reported the degradation of crude oil by 97 % by the combined effect of iron oxide NPs synthesized using Aerva lanata floral part and biosurfactant produced by Bacillus subtilis and Paenibacillus dendritiformis . Similarly, Muthukumar et al. documented the bacterial species Pseudomonas aeruginosa and iron NPs having 5–50 nm size able to synergistically remediate 67 % of ANT. Nickel oxide NPs achieved 79 % degradation of PYR at 2 μg/mL ANT within 60 min under UV and sunlight, confirmed by XRD and SEM analysis showing cubic crystalline structures sized 37–126 nm . Nanomaterials are crucial for addressing hazardous contaminants . Bioelectrochemical systems are versatile, and used in bioremediation, biosensors, microbial fuel cells, and microbial electrolysis cells. When combined with nanotechnology, they significantly enhance the degradation of PAHs. This integration boosts efficiency and effectiveness in environmental cleanup . Besides this advanced research, emphasis is placed on understanding microbial influences on nanomaterials and their effects on toxicity, transport, fate, and bioaccumulation. Developing systems to monitor, detect, and treat trace contaminants in air, water, and soil is crucial for sustainable pollution management . Section title: Challenges and consideration Educational score: 4.021438121795654 Domain: biomedical Document type: Review Language: en Nanomaterials offer significant advantages in the bioremediation of PAHs due to their high surface area-to-mass ratio, enhanced reactivity, and improved mobility, which enable efficient pollutant degradation. These materials stand out due to their unique characteristics, particularly a significantly increased surface-to-volume ratio as well as enhanced magnetic and catalytic traits compared to their bulk counterparts. Quantum size effects at the nanoscale enhance the efficacy of catalytic processes by modifying electronic structures. They can act as catalysts and be tailored for specific contaminants, making them versatile and cost-effective for large-scale applications. However, potential toxicity to microorganisms, environmental persistence, and high production costs poses challenges. Additionally, the interactions between nanomaterials and microbial cells are not fully understood, and there are regulatory hurdles and risks of unintentional ecological impacts . Section title: Challenges and consideration Educational score: 4.293011665344238 Domain: biomedical Document type: Review Language: en A significant limitation of nanomaterials lies in their potential environmental impact, as their uncontrolled release can lead to widespread harm to abiotic and biotic components of ecosystems, including microorganisms, algae, plants, and animals . Compared to their bulk counterparts, the raised surface area to volume ratio of NPs results in increased reactivity and efficacy; however, their attributes are parallel to their parent chemical species. Consequently, their active participation in diverse physicochemical and biochemical processes within the environment can have detrimental effects on ecological systems. Certain metal NPs such as ZnO, AgO, CuO, and Fe 2 O 3 are recognized for their toxicity and antimicrobial properties, particularly when present in excessive quantities . Challenges include the long-term presence of NPs in the environment their accumulation in organisms, potential for toxicity. The nano-size attributes provide a high surface area and enhanced adsorption capabilities. However, NPs smaller than 20 nm may pose nanotoxicity risks. Small size NPs able to penetrate beneath the microbial cell causing cell malfunction . Section title: Challenges and consideration Educational score: 4.042906761169434 Domain: biomedical Document type: Study Language: en The challenges also lie in the intricacies of soil complexity. Understanding the behavior of NPs within the soil is a complex task, primarily because of the solid phase nature of the soil and the interactions NPs engage in with soil constituents, including charged humic acids and clay particles. Many studies about NPs have focused on soil suspensions rather than intact soil, as analyzing and characterizing NPs within the soil matrix presents significant difficulties. The utilization of physico-chemical methods to eliminate these NPs from soil and water may prove impractical due to cost inefficiency and environmental concerns. Moreover, the high production costs associated with NPs and their integration with microbial processes pose significant obstacles to scaling up and implementing these techniques on a larger, more practical scale. Hence, a pressing requirement exists to pioneer an eco-friendly, sustainable, and cost-effective bioremediation technology that can specifically target and address these issues. As nano-bioremediation is still in its evolving stage, there is a critical need for standard guidelines governing the application of nanomaterials in bioremediation practices. Section title: Ethical and environmental implications Educational score: 4.183862209320068 Domain: biomedical Document type: Review Language: en Health concerns arise from the potential adverse effects of NPs when inhaled, ingested, or absorbed through the skin, raising questions about occupational safety and consumer exposure. The long-term effects of NPs exposure on human health and the environment remain uncertain, requiring ongoing research . It poses significant threats to biological models, and biomarkers including cell death, oxidative stress, DNA damage, apoptosis, and inflammatory responses . Nanomaterial toxicity, which can vary based on size, shape, and surface chemistry, complicates safety assessments. The risk of unintended NPs release during production, use, and disposal poses potential threats to ecosystems and human health. Regulatory and ethical challenges include establishing safety standards, monitoring environmental release, and addressing ethical concerns related to misuse, such as in surveillance and minimizing direct contact with humans. Balancing innovation with ethical considerations and developing strong governance frameworks are essential to ensure the responsible use of nanotechnology in bioremediation . Section title: Future research directions Educational score: 4.008016109466553 Domain: biomedical Document type: Review Language: en The future of nanomaterials in bioremediation appears promising, as ongoing research is focused on improving their sustainability and efficacy. Improvements in the synthesis and modification of nanomaterials are anticipated to enhance their stability, reactivity, and adsorption capacities in a variety of environmental conditions. The objective of upcoming research is to create nanomaterials that are cost-effective, biodegradable, and non-toxic by optimizing the formulation process at the nanoscale. Furthermore, the integration of nanomaterials with biochar, immobilized enzymes, and electrokinetic methods could provide a variety of approaches to expedite the degradation of PAHs and other contaminants. The potential for eco-friendly and sustainable remediation solutions is further enhanced by the use of biogenic nanomaterials and genetically modified organisms. Understanding the behavior of NPs within soil is a complex task, primarily due to the solid-phase nature of the soil. However, large-scale production of NPs may reduce expenses, and their reusability can make them a realistically cost-effective solution for environmental remediation. Section title: Future research directions Educational score: 4.0093536376953125 Domain: biomedical Document type: Review Language: en Bioremediation efficacy and microbial metabolic activity can be improved by incorporating “omic” approaches, including transcriptomics, proteomics, and metabolomics. By facilitating the precise monitoring and optimization of remediation processes, the integration of artificial intelligence and machine learning techniques in phytoremediation has the potential to transform the field. The successful implementation of nanomaterials in large-scale bioremediation initiatives will be contingent upon the resolution of challenges related to nanotoxicity, environmental persistence, and implications. In general, the ongoing investigation and innovation in this field hold significant potential for the effective and sustainable management of environmental contamination. Section title: Conclusion Educational score: 4.116848468780518 Domain: biomedical Document type: Review Language: en PAHs, known for their mutagenic and carcinogenic properties, pose substantial threats to human health and ecosystems. Their hazardous nature emphasizes the need for effective remediation methods. Nanomaterials, including metal oxides, CNTs, biopolymers, and nanoscale zeolites, have gained attention due to their potential for remediation. Their small size and significant surface area-to-volume ratio make them valuable tools for improving the adsorption and biodegradation of PAHs in contaminated soil. It is understood from the review that nano-bioremediation exhibits a higher removal efficiency of PAHs compared to traditional bioremediation. This would mean that the application of NPs could enhance the bioremediation process, leading to a more significant reduction in PAH contamination. The strategies such as nanomaterial-assisted microbial degradation, microbial cell immobilization on nanomaterials, and promoting microbial activity through enzymes and electron transfer mediated by nanomaterials provides for enhanced removal of PAHs. These approaches exhibit the versatile role of nanomaterials in upregulating PAH elimination processes, thereby ameliorating the effectiveness of bioremediation techniques. Section title: Conclusion Educational score: 3.97613787651062 Domain: biomedical Document type: Review Language: en The use of biogenic nanomaterials, synthesized through microorganisms and plant extracts, offers a sustainable approach to PAH degradation by utilizing microbial enzymes and plant compounds as reducing agents, aligning with green chemistry principles. Future research in nano-bioremediation will likely focus on developing optimization systems, standard protocols, and health safeguard standards for remediating PAHs from the environment. Additionally, standardizing the recovery process of NPs will help reduce production costs. Extending the application of nanomaterials to large-scale bioremediation by integrating other remediation approaches will aid in overcoming challenges and enhancing degradation capability. A standard protocols and regulations might help for a responsible application of nanomaterials in bioremediation endeavors to eliminate PAHs from the environment with a sustainable approach. Section title: CRediT authorship contribution statement Educational score: 0.9863011837005615 Domain: other Document type: Other Language: en Nitu Gupta: Writing – original draft, Visualization, Software, Resources, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Apurba Koley: Writing – review & editing, Software, Formal analysis, Data curation. Sandipan Banerjee: Writing – review & editing, Software, Methodology, Formal analysis, Data curation. Anudeb Ghosh: Writing – review & editing, Methodology, Formal analysis, Data curation. Raza Rafiqul Hoque: Writing – review & editing, Validation, Supervision, Project administration, Methodology, Conceptualization. Srinivasan Balachandran: Writing – review & editing, Validation, Supervision, Project administration, Methodology, Conceptualization. Section title: Disclosure statements Educational score: 0.9629508852958679 Domain: other Document type: Other Language: en The authors declare that there are no conflicts of interest as far as they aware of. Section title: Funding Educational score: 1.0071338415145874 Domain: other Document type: Other Language: en This work was supported by the 10.13039/501100001407 Department of Biotechnology , India, under the 10.13039/501100001407 DBT Twinning Project [No. BT/PR25738/NER/95/1329/2017 dated December 24, 2018]. Nitu Gupta acknowledged the funding provided by the 10.13039/501100001501 UGC NET- 10.13039/100003289 JRF Fellowship through 10.13039/501100012624 Tezpur University , Tezpur, India. Apurba Koley is financially supported by BEFWAM project: Bioenergy, Fertilizer and Clean water from Invasive Aquatic macrophytes [Grant Ref: BB/S011439/1]. Section title: Ethical Approval Educational score: 1.0706669092178345 Domain: other Document type: Other Language: en Research does not report on or involve the use of any animal or human data or tissue. Section title: Consent to participate Educational score: 1.0266131162643433 Domain: other Document type: Other Language: fr Not applicable. Section title: Consent for publication Educational score: 0.8673436641693115 Domain: other Document type: Other Language: en All the authors gave consent for the publication of this journal. Section title: Data availability Educational score: 0.6840232014656067 Domain: biomedical Document type: Other Language: en Data supporting this study are included within the article. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Study | biomedical | en | 0.999998 |
PMC11698355 | Section title: Background Educational score: 4.054279804229736 Domain: biomedical Document type: Review Language: en Gastrointestinal tract (GI) cancers, comprising oral, gastric, and colorectal malignancies, impose a huge burden on global health. These cancers are responsible for one-quarter of oncological diagnoses and approximately one-third of cancer-related deaths. 1 Screening and surveillance pathways have helped reduce the incidence rate of certain forms of these cancers. For example, the use of colonoscopy to remove precancerous polyps has become the paradigm of an effective cancer-reducing intervention. 2 However, interventional endoscopy isn’t a ‘magic bullet’ as it does not necessarily prevent cancer development in certain GI organs such as the stomach. 3 In addition, issues such as poor patient adherence to endoscopy screening (∼ only 75%), financial cost , and accessibility to adequate infrastructures in remote and deprived regions, hinder the optimization of screening programes. As a consequence of the aforementioned factors, only about 10% of GI cancers are diagnosed via screening programes. Therefore, evaluation of accessible and economical cancer prevention strategies remains the mainstay of current clinical aspiration. Section title: Background Educational score: 3.9561171531677246 Domain: biomedical Document type: Review Language: en Environmental factors such as a low-quality diet (i.e., dietary habit comprising of high saturated fats/trans-fats, highly processed, low fiber, high salt, and/or high sugar content meals) and smoking significantly influence the development of GI cancers. 4 These risk factors bring about a chronic inflammatory state that creates the conducive microenvironment which enables the multi-step process preceding the development of malignancy in mucosal tissues. Consequently, the use of anti-inflammatory agents has garnered attention for a potential role in cancer prevention, particularly chemoprevention. Section title: Background Educational score: 3.9852964878082275 Domain: biomedical Document type: Review Language: en Chemoprevention entails the use of chemical agents (natural or synthetic) to inhibit or delay cancer development. Jankowski and Hawk summarized all key chemoprevention agents in their review, ranging from aspirin, acid suppression, hormone replacement therapy (HRT) to fish oil. 5 These agents have the potential to impair dysfunctional protein activities that lead to initiation, promotion, and progression of tumorigenesis. As chemoprophylactic agents reduce malignant properties and tendencies, they could ultimately play a significant role in anticancer and systemic cancer treatment strategies. 6 Section title: Background Educational score: 4.252409934997559 Domain: biomedical Document type: Study Language: en Importantly, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) have chemoprotective properties against cancer via multiple pathways. Grancher and colleagues have illustrated these pathways ; most importantly, they demonstrated the ability of aspirin to irreversibly inhibit cyclooxygenase-2 (COX2) enzyme and the subsequent production of prostaglandin E2 (PGE 2 ). COX-2 and PGE 2 are inflammatory mediators released by tumour cells, and they induce apoptosis, cell migration, invasion, and angiogenesis, thus the progression of carcinogenesis. 7 Section title: Background Educational score: 3.2692761421203613 Domain: biomedical Document type: Review Language: en The aim of this paper is to discuss existing data that promotes the use of aspirin as a prophylaxis for GI cancers. Section title: Method Educational score: 3.999216318130493 Domain: biomedical Document type: Study Language: en English-language studies dating back to year 2006 were identified manually by the lead author. Publication search engines used in this search were Cochrane and PubMed. Key terms included in the search were gastrointestinal, esophageal, gastric, colorectal, and hepatobiliary cancer, and aspirin chemoprevention. A manual search of articles within the reference lists of publications was also conducted. This paper explores data which covers the use of aspirin as a chemoprophylaxis for GI and digestive tract cancers, the data reviewed are from randomized control trials (5), meta-analysis (3), cohort studies (2), and population-based studies (1), and the studies excluded are i) research that assesses non-aspirin anti-inflammatory agents as a chemoprophylaxis and ii) research that did not stratify the types of GI or digestive tract cancers. Existing guidelines on aspirin use as a chemoprophylaxis were identified via manual search. Section title: Supporting evidence Educational score: 2.7986648082733154 Domain: biomedical Document type: Study Language: en Many studies have demonstrated that the use of NSAIDs lowers the risk of GI cancers ( Table 1 ). 8 Section title: Colorectal cancer (CRC) Educational score: 4.062294960021973 Domain: biomedical Document type: Study Language: en Ren et al.’s UK Biobank cohort study with over 300,000 participants illustrated that regular use of COX-PGE 2 inhibiting NSAIDS lowers the incidence of CRC by 36%. 9 Aspirin has been the preferred NSAID due to its safer toxicity profile, and the vast knowledge base it has compared to other agents like celecoxib. A dose of aspirin as low as 81 mg daily inhibits COX-PGE 2 mechanism by 45%, whereas other agents such as ibuprofen required much higher doses, such as 800 mg four times daily for a 63% decrease in PGE 2 synthesis. 10 Section title: Colorectal cancer (CRC) Educational score: 4.060510158538818 Domain: biomedical Document type: Study Language: en Interestingly, regular aspirin use has been associated with protective changes in the gut microbiota. Particularly, aspirin intake prevents the growth of some pro-inflammatory bacteria that promote neoplastic transformation in the gut. Prizment et al.’s randomized control trial (RCT) supports this; they found a difference in the diversity and proportionality of varied bacteria within the gut microbiota of patients taking aspirin compared to the placebo cohort. For example, a larger proportion of Akkermansia bacteria was seen in patients taking aspirin. Akkermansia is known for its beneficial impact in colonic health. 11 Section title: Colorectal cancer (CRC) Educational score: 4.023904800415039 Domain: biomedical Document type: Study Language: en Rothwell and colleagues also reported that the prophylactic effects associated with aspirin were stronger with tumors within the proximal colon, the burdensome site where tumors are usually missed during colonoscopy. 12 Similarly, Hull et al.’s ‘seAFOod Polyp Prevention Trial’ which evaluated the effect of omega-3 and aspirin on the reduction of colorectal adenomas, found that aspirin was the only chemoprotective agent that decreased the number of adenomas in the proximal colon. Colorectal adenoma was explored, given that it’s a well understood pathological predictor for CRC development, but they were unable to conclude that both drugs significantly reduced risk of CRC development in high-risk individuals. Nevertheless, both aspirin and omega-3 decreased the number of colorectal adenomas in participants at year 1 of colonoscopy surveillance. 13 It is probable that significant benefit was not deduced as the research was run for only a short time (1 y). It is therefore likely that the study was underpowered as the benefits of chemopreventative measures are typically delayed by at least several years. Section title: Esophageal and gastric cancers Educational score: 3.973010301589966 Domain: biomedical Document type: Review Language: en In addition to CRC, other GI cancers have had favorable associations with low dose aspirin (LDA) therapy, Garcia et al showed that the use of LDA as low as 75 mg daily for at least 1 y was associated with a 41% and 54% risk reduction for esophageal and gastric cancer, respectively. Even though they found an increasing benefit with the duration of LDA use, there was no significant difference when comparing the duration of 1 to 3, 3 to 5 or >5 yrs. 14 On the contrary, Rothwell’s meta-analysis showed that the benefit was strongest after 10 to 20 yrs follow up. 12 This suggests the benefits of LDA use are much delayed than expected and it would ideally benefit individuals who are able to take aspirin for a lengthened duration of time. Thus, more research is required to help form an informative guideline which incorporates factors such as patient age and duration of aspirin use. Section title: Esophageal and gastric cancers Educational score: 4.083901405334473 Domain: biomedical Document type: Study Language: en The ‘AspECT’ trial by Jankowski and colleagues evaluated the benefits of aspirin and proton pump inhibitors (PPIs) in precancerous metaplasia i.e., Barrett’s esophageal adenocarcinoma, and the mortality caused by both diseases. They found both drugs protected against all-cause mortality. However, high-dose PPI was the most protective of the two; it significantly prevented the progression of Barrett’s’ to cancer. The most impactful finding from this study was the additive chemoprotective effect of both drugs; the greatest protection and survival was found with the concurrent use of high-dose PPIs and LDA. 15 Furthermore, serious adverse events from concurrent use of both agents were exceptionally low, less than 1%. Section title: Hepatobiliary (HPB) and pancreatic cancers Educational score: 4.118814468383789 Domain: biomedical Document type: Study Language: en There is also some evidence that aspirin might be beneficial in other digestive tract cancers. However, research here is not as extensive as that of GI luminal gut cancers. The meta-analysis conducted by Bosetti et al acknowledged that aspirin’s chemoprotective effect is present in HPB and pancreatic cancers. They found a stronger relative risk (RR) in liver cancers e.g., hepatocellular (HCC) than cholangiocarcinoma (Liver; RR of 0.71, 95% confidence interval (CI) 0.46 – 1.09, Cholangiocarcinoma; RR of 0.53 95% CI 0.24 – 1.14). Regarding pancreatic cancers an inverse relationship with aspirin was seen; a 20% deduction in pancreatic cancer risk was reported, which contradicts their previous study that found no significant reduction. 8 In similarity to benefits seen in GI cancers, the protective effects seem to also increase with longer duration of aspirin use. 8 Although liver cancers have the highest impact from aspirin (amongst HPB subgroup), the reports of chemo-preventative benefit are inconsistent and has been identified mainly in hepatitis B-virus related HCC. 16 Section title: Hepatobiliary (HPB) and pancreatic cancers Educational score: 3.938037157058716 Domain: biomedical Document type: Review Language: en Controversial findings seen in HPB, and pancreatic cancers could be due to the more diverse etiological factors that progress into malignancy. In correspondence to GI cancers, risk factors such as advancing age, alcohol and smoking predispose the chronic inflammatory changes that lead to neoplastic transformation. However, HPB and pancreatic cancers have a wider range of risk factors such as diabetes mellitus, cholelithiasis, and infections such as hepatitis and liver fluke. 17 These all potentially have varied mechanisms which may or may not incorporate COX-2 pathway. Therefore, more research is still required to review the potential of chemoprophylaxis in this subgroup. Other chemical agents, that have been associated with reduced risk of these cancers include statins and metformin. 18 , 19 Section title: Potential limitations for regular aspirin use Educational score: 3.9964404106140137 Domain: biomedical Document type: Review Language: en So far, the main hesitancy towards the consideration of aspirin as a prophylaxis for GI cancers is the risk of hemorrhage. Ingestion of aspirin leads to the inhibition of thromboxane-A2 platelet aggregation; as a result, bleeding time is prolonged, and this could last hours to days as this inhibitory process could persist throughout the platelet cells’ life span. 20 Major hemorrhagic events come with significant complications such as bleeds which require transfusions, intracranial hemorrhage that can lead to neurological deficit or death. Thus, the benefit of regular LDA use is becoming increasingly questioned in day-to-day clinical practice, especially its use as a primary prevention for cardiovascular diseases (CVD) or strokes in the older population. Section title: Potential limitations for regular aspirin use Educational score: 4.023497104644775 Domain: biomedical Document type: Study Language: en Aspirin and other NSAIDS also cause GI wall damage, leading to ulcers and predisposition to GI bleeds. In fact, it has been advised that routine prescription of doses higher than 81 mg should be avoided due to dose-dependent adverse effects. 21 However, in the aforementioned AspECT Trial, the combined use of LDA and PPIs had an exceptionally low GI bleed rate ∼ <0.1% over 9 yrs. 15 Section title: Existing guidelines and promising studies Educational score: 4.034111976623535 Domain: biomedical Document type: Review Language: en The use of aspirin in GI cancer prevention has been incorporated in some countries, albeit with some variations in recommended dosage and target populations. Australia implemented LDA use for CRC prevention in their general population in 2017. There, Cancer Council Australia released a guideline recommending daily use of 100 to 300 mg aspirin for 2.5 to 5 yrs amongst people aged 50 to 70 yrs. 22 Thereafter, RCTs such as the ‘Should I take Aspirin trial’ (SITA) trial were initiated to guide patients’ decision on aspirin use. Although, the SITA trial revealed that exposure to the decision aid they designed prompted participants to discuss aspirin with their care provider, there was no statistical evidence to show that it led to an increase in the uptake of regular aspirin. 23 This suggests that clinical knowledge is not enough to guide patients’ informed choices, and these clinical encounters could benefit from the addition of a clinical scoring system. Whereby, clinicopathological risk factors (such as nutritional status or predisposition to chronic GI inflammation) that estimate patients’ likelihood of developing colorectal cancer are used alongside decision aids. Section title: Existing guidelines and promising studies Educational score: 3.817220687866211 Domain: biomedical Document type: Other Language: en In England, the National institute for health and Care Excellence (NICE) released a new guideline for an off-label use of daily aspirin for people living with lynch syndrome to decrease their risk of CRC. However, their recommended dose has not been decided and current practice is to use 150 to 300 mg aspirin. 24 The United States proposes aspirin prophylaxis in a multi-systemic fashion. They have initiated a dual recommendation where individuals aged 50 to 59 yrs with a ≥ 10% likelihood of developing CVD in 10 yrs, and who also have an inherited risk of colorectal cancer are advised to take up LDA for at least 10 yrs for primary prevention of CVD and CRC. 25 Section title: Existing guidelines and promising studies Educational score: 4.042029857635498 Domain: biomedical Document type: Study Language: en Within the world of oncology, the impressive benefits of aspirin have also been noted in non-GI cancers such as breast and prostate cancer, as its use have led to better cancer outcomes. 26–28 Coyle et al are currently running a phase III trial, the ‘ADD-aspirin trial. This trial is assessing the use of 100 and 300 mg aspirin for prevention of cancer recurrence. Patients treated for early-stage breast, colorectal, gastric, esophageal, and prostate cancers have been recruited and will be revaluated after ≥ 5yrs of aspirin use. 29 Such an integrative trial is promising, as it can help weigh risk and benefits, and thus help with a much distinct guideline, as people who have previously had cancer have a substantial risk of relapse or developing new cancers. Section title: Existing guidelines and promising studies Educational score: 4.0068039894104 Domain: biomedical Document type: Review Language: en The 5-year survival rate for localized and distant CRC is 91% and 13% respectively. 30 The sizeable difference in the estimated outcome between these CRC extremes illustrates the significant burden posed by disease progression. On this account, it would be worthwhile to generate further guidelines where prognostics factors such as the manner of surgery (radical or non-radical), genetic mutations such as TP53, and/or basic blood tests such as albumin level are incorporated to recommend aspirin prophylaxis to improve disease outcome. Several scoring systems such as Gustave Roussy Immune (GRIm-Score), MD Anderson Cancer Centre (MDACC), Royal Marsden Hospital (RMH) scores that use diverse clinicopathological parameters have been generated and are currently being used to guide prognostication and patient selection for clinical trials. 31 , 32 Section title: Discussion Educational score: 3.5460636615753174 Domain: biomedical Document type: Review Language: en Aspirin is readily available and is one of the most used drugs globally. Its potential as a preventative measure against GI cancers is supported by a growing body of evidence. Aspirin’s beneficial association is not limited to chemoprevention; its preventative effects are well known in ischaemic diseases such as stroke and myocardial infarction. 33 Thus, regular aspirin use benefits overall morbidity and mortality, and possibly lengthens an individual’s lifespan. Section title: Discussion Educational score: 3.898724317550659 Domain: biomedical Document type: Review Language: en The main limitation with the use of aspirin is its link with hemorrhage. However, there are many factors to bear in mind when understanding the bleeding risks. Some of these risks, such as GI hemorrhage are curbed with the use of PPIs; their synergistic uptake has been proven to enhance chemoprevention in cancers such as esophageal cancer. Even though aspirin inhibits coagulation cascades, its use is usually not the primary cause of bleed, and research has shown that other factors, such as Helicobacter pylori exposure and chronic hypertension, exacerbate the clinical impact of hemorrhaging arterioles and capillaries. 34 Section title: Discussion Educational score: 3.6667323112487793 Domain: biomedical Document type: Review Language: en So, we know that aspirin works; we can appreciate that a dose as low as 75 mg daily is effective; and furthermore, we know that the longer a patient uses aspirin, the more likely they will gain the chemoprotective benefits over time. As seen in current studies, a 10-year duration is associated with the reduction of GI cancer risk; thus, the ideal population would be middle-aged patients who have been deemed to have low bleeding risk following a risk assessment by their care provider. Regarding recommendations for HPB and pancreatic cancers, there are some benefits, but more research is still required to deduce considerable conclusions. Section title: Discussion Educational score: 3.9607903957366943 Domain: biomedical Document type: Review Language: en On a molecular level aspirin impacts on multiple cancer signaling pathways and studies have also illustrated the benefits of aspirin across many digestive tract cancers. Although for some cancers the benefits are more modest than others. The existing aspirin-GI chemoprevention guidelines discussed earlier have different recommendations for aspirin use. For example, in Australia it is recommended for a specific age bracket, whilst in the UK it is recommended for patients with lynch syndrome. This further emphasizes the need for more research on how to best implement aspirin chemoprophylaxis. All aspects considered it remains clear that aspirin use makes sense. As deduced from the SITA study more measures are also required to reinforce patient decision aids and thus, successfully implement aspirin introduction for GI cancer prevention. Additionally, benefits of aspirin in established cancer patients are also being uncovered. Section title: Discussion Educational score: 3.508185625076294 Domain: biomedical Document type: Study Language: en Whilst the facts discussed in this paper are from published sources, there are some limitations that should be acknowledged. Firstly, no statistical analysis was performed and the discussions in this paper are based on previously published research. Secondly, a few of the reports were from case control studies which are prone to biases such as recall, selection, or interviewer bias. Also, similar to any research that looks at the relationship between factors such as lifestyle or medication history to a specific disease, there is usually a risk of healthy population bias where participants are possibly healthier than the general population. Therefore, the presence of other external factors could potentially augment the good results seen from regular aspirin use. Section title: Discussion Educational score: 3.9201009273529053 Domain: biomedical Document type: Review Language: en In conclusion, the use of LDA as a chemoprophylaxis has a huge role in the future of gastrointestinal cancer prevention schemes. Low-cost cancer prevention schemes are readily used in other medical fields e.g., the use of retinoids and sunscreen in dermatology, for skin cancer incidence. 35 , 36 Therefore, application of these chemoprophylaxis findings into day-to-day clinical practice is promising, especially for patients who are at increased risk or who have previously had GI cancers. There are still some loopholes in the interpretation of the existing studies. Firstly, an agreed dose needs to be determined; more work is still required in the future to help determine the lowest effective dose that would inhibit micro-oncogenic inflammatory processes without causing harm. Secondly, the complexity of drug history and existing comorbidities in middle aged adults’ results in some level of uncertainty regarding the exact effect of aspirin. For instance, patients who are on regular aspirin, tend to be on statins also, which both have an influence in GI chemoprevention. Thus, these confounding factors need to be considered in future research. Section title: Take home message Educational score: 2.357132911682129 Domain: biomedical Document type: Other Language: en Avoid aspirin if you have had an allergy to it or have risks of bleeding in the GI tract (GI ulcers or Inflammatory bowel disease) or brain (aneurysm or high blood pressure). Section title: Take home message Educational score: 2.246868371963501 Domain: biomedical Document type: Other Language: en Consider taking aspirin for 5–10 yrs, sometime between 50–70 yrs of age, to maximize the benefits and minimize the risks. Section title: Take home message Educational score: 2.7237441539764404 Domain: biomedical Document type: Other Language: en Combination of aspirin and acid suppression agents seems synergistic in esophageal cancer. | Review | biomedical | en | 0.999995 |
PMC11698378 | Section title: Introduction Educational score: 4.110666275024414 Domain: biomedical Document type: Review Language: en Sentinel lymph node biopsy (SLNB) is the established technique for staging clinically node-negative breast cancer. SLNB, first described by Giuliano et al. in 1994, has superseded the need for axillary lymph node dissection (ALND) as the standard procedure . The minimally invasive nature of SLNB reduces the morbidity associated with ALND . The use of a radiotracer in combination with blue dye has resulted in sentinel node detection rates of up to 97% . Therefore, SLNB using a radioisotope with blue dye is the gold standard for intraoperative axillary node assessment . Section title: Introduction Educational score: 3.996487855911255 Domain: biomedical Document type: Other Language: en Technetium-99m (99mTc), a metastable nuclear isomer of technetium-99, is the most commonly used radiotracer for SLNB . Subareolar or peritumoral radioisotope dye injection is performed preoperatively . 99mTc decays into its ground state through gamma emissions permitting the intraoperative assessment and identification of positive nodes using a gamma probe . Blue dye also may be used to stain positive lymph nodes . 99mTc is generally considered safe for both patients and staff; however, the radioactive nature of the isotope results in the strict regulation of its use, management, and disposal to prevent unintended contamination . Furthermore, 99mTc is not easily accessible in most parts of the world, and the increased costs associated with the special handling required of the radiotracer limit the expansion of conventional SLNB . Section title: Introduction Educational score: 3.980581045150757 Domain: biomedical Document type: Study Language: en Superparamagnetic iron oxide nanoparticles (SPIO) have been studied as an alternative to radioisotope tracers for SLNB . The superparamagnetic properties of the nanoparticles allow for high spatial resolution and sensitivity through the detection of the net magnetization of the particles when an external magnetic field is applied . Magtrace® (Endomagnetics Limited, Cambridge, United Kingdom) has been introduced as an SPIO-based tracer which can be detected using the SentiMag® handheld probe (Endomagnetics Limited, Cambridge, United Kingdom) . The use of SPIO-based agents in staging the axilla, which has been studied in different trials, has shown non-inferiority to the 99mTc for axillary SLN detection in early-stage breast cancer . Section title: Introduction Educational score: 3.9415476322174072 Domain: biomedical Document type: Other Language: en Given the equivalence of SPIO-based tracers to the current gold standard, it may be preferential to the 99mTc-based radiotracer due to the logistical benefits associated with SPIO. Firstly, since SPIO-based tracers are not radioactive, there is no requirement for the special handling and disposal of the dye itself and any consumable equipment contaminated by the radioactive dye . Furthermore, Magtrace® can be injected up to 30 days prior to the procedure, unlike the radiotracer which can only be injected up to a maximum of 24 hours prior to the procedure owing to the six-hour half-life of the isotope . This allows for increased flexibility for the patient. Additionally, the increased buffer time allows for redundancy in case of operating list delays or cancellations which is not possible with the radiotracer . Section title: Introduction Educational score: 4.12477970123291 Domain: biomedical Document type: Study Language: en The aim of this study was to evaluate the potential equivalency of the new Magtrace® and SentiMag® techniques in comparison to the "gold standard" technique using 99mTc-based radiotracer. The primary outcome was the node detection rate per patient and the number of lymph nodes retrieved. The secondary outcome was the postoperative length of stay and postoperative complication rates . Section title: Materials and methods Educational score: 4.014128684997559 Domain: biomedical Document type: Study Language: en We conducted a retrospective cohort study at the Rotherham NHS Foundation Trust, UK. The study period was from October 1, 2021, to January 31, 2022. The study data was collected from physical and digital patient medical records. A master list of all adult female patients who underwent breast surgery with SLNB for invasive breast cancer was compiled. This was then stratified into two groups: the "control" group using the 99mTc radiotracer and the "intervention" group using Magtrace. Thirty patients were randomly assigned to each group using simple random sampling. Ethical approval was obtained from the Local Ethics Department of the Rotherham NHS Foundation Trust . Section title: Materials and methods Educational score: 3.7940804958343506 Domain: biomedical Document type: Study Language: en The inclusion criteria for this study were as follows: primary breast cancer stages T1-T3 and >18 years of age of any gender. Patients who underwent neoadjuvant chemotherapy were excluded as well as any metastatic disease at the diagnosis. Additional exclusion criteria were pregnancy, previous axillary surgery, radiation therapy to the axilla, or impaired axillary lymphatic function. Section title: Materials and methods Educational score: 3.211731195449829 Domain: biomedical Document type: Study Language: en The primary endpoint for this study was the nodal detection rate. The number of nodes retrieved, postoperative complications, and the total length of stay were measured as the secondary outcomes. Section title: Materials and methods Educational score: 2.914477825164795 Domain: biomedical Document type: Study Language: en Categorical variables were compared using Fisher's exact test. Student's t-test was performed to compare continuous variables. A p-value of <0.05 was considered statistically significant. All statistical tests were performed using MATLAB version: 9.14.0 (The MathWorks Inc., Natick, Massachusetts, United States; https://www.mathworks.com ). Section title: Results Educational score: 1.456114649772644 Domain: biomedical Document type: Other Language: en Patient characteristics Section title: Results Educational score: 4.075685501098633 Domain: biomedical Document type: Study Language: en We analyzed a total of 60 patients, of which 30 received SLNB using Magtrace® and 30 received SLNB using 99mTc. The mean age of all patients was 64.25±11.6 (33-85) years. Between both groups, the mean ages were slightly dissimilar, but not statistically significant (Magtrace®: 66.9±11.8 vs. 99mTc: 61.6±11.1; p=0.077). The mean BMI of all patients was 28.8±6.2 (16-47). BMI was similar in both groups (Magtrace®: 29.8±6.7 vs. 99mTc: 27.9±5.8; p=0.189). Other patient characteristics such as tumor lateralization, tumor and nodal stage, tumor histopathology, and estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER-2) status were similar and are shown in Table 1 . Section title: Results Educational score: 1.7272286415100098 Domain: biomedical Document type: Other Language: en Intraoperative characteristics Section title: Results Educational score: 4.129146575927734 Domain: biomedical Document type: Study Language: en We found the total operative time matched for patients who only had wide local excision (WLE) with SLNB to be statistically significantly higher in the Magtrace® cohort than the 99mTc cohort (Magtrace®: 89.0±36.9 (30-146) minutes vs. 99mTc: 69.4±17.6 (36-101) minutes; p=0.012). We also found the surgery type between the two groups to be significantly variable with a p-value of 0.049. The breakdown of surgery type can be seen in Table 2 . Section title: Results Educational score: 3.652834892272949 Domain: biomedical Document type: Study Language: en Nodal detection was similar in both cohorts; however, the 99mTc cohort had a 100% nodal detection rate compared to 93.3% with Magtrace®. Nonetheless, the results were statistically comparable in our study. Additionally, lymph node retrieval and SLN detection were similar with both techniques. The detailed characteristics have been documented in Table 2 . Section title: Results Educational score: 1.6048096418380737 Domain: biomedical Document type: Other Language: en Postoperative characteristics Section title: Results Educational score: 4.054125785827637 Domain: biomedical Document type: Study Language: en The median length of stay was identical in both groups at postoperative day 1 (p=1). We found an overall complication rate of 20% (n=12): eight complications in the Magtrace® group and four complications in the 99mTc group. Axillary seroma was the most common complication (n=10), with six axillary seromas developing in the Magtrace® cohort and four seromas developing in the 99mTc cohort. Additionally, there was one instance of breast superficial skin necrosis in the Magtrace® group. There was no statistical significance between complication rates in the two cohorts with a p-value of 0.333 as shown in Table 2 . Section title: Discussion Educational score: 3.690594434738159 Domain: biomedical Document type: Study Language: en Our study aimed to evaluate the role of Magtrace® at our district general hospital by comparing its efficacy with the established gold standard 99mTc radioisotope-based SLNB. This novel technique has already demonstrated its efficacy and equivalence in trial settings. However, our aim was to determine whether these results can be replicated in everyday practice. Section title: Discussion Educational score: 4.1060991287231445 Domain: biomedical Document type: Study Language: en Our primary outcome measure was the nodal detection rate. We found no statistical significance in the nodal detection rate which supports the findings in published literature. The SentimagIC trial established Magtrace® as non-inferior to 99mTc radioisotope-based SLNB by undertaking nodal detection with Magtrace®, followed by confirmation using the dual tracer method. In this study, the dual tracer method identified nodes in 98.6% of patients, while the magnetic tracer identified nodes in 99.3% of patients . Furthermore, there was a 100% concordance between dual tracer and magnetic tracer node detection . Our study reflects similar findings with a 93.3% node detection rate in the Magtrace® arm and a 100% node detection rate in the 99mTc arm. Section title: Discussion Educational score: 3.8727328777313232 Domain: biomedical Document type: Study Language: en The number of lymph nodes retrieved was similar in both cohorts. Nevertheless, SPIO-based tracers have been associated with higher nodal retrieval rates in a meta-analysis conducted by Karakatsanis et al. in 2016 . It has been hypothesized that increased nodal retrieval may be associated with increased postoperative morbidity; however, no such association has been proven. Conflicting results have been reported in the literature following the 2016 meta-analysis with Shams et al. also finding a significant association between magnetic tracers and an increased node retrieval rate, whereas the SMART study found no difference between their cohorts. Section title: Discussion Educational score: 4.092191696166992 Domain: biomedical Document type: Study Language: en Our study found the total operative time to be significantly higher in the Magtrace® cohort versus the 99mTc tracer group (89.0±36.9 minutes vs. 69.4±17.6 (36-101) minutes; p=0.012, respectively). As this was a retrospective study, we were unable to acquire data for lymph node detection time alone. Furthermore, due to there being a significant variation in the procedures performed between the groups, an accurate conclusion cannot be drawn in this regard due to the possible confounding effect. There is a relative paucity in the literature regarding the differences in the mean operative time between both techniques; however, Shams et al. did report no difference in the mean operative time in their study. Section title: Discussion Educational score: 3.1909425258636475 Domain: biomedical Document type: Study Language: en With an identical postoperative length of stay in both groups and no significant difference in postoperative complications, this was a secondary outcome measure that we had specified at the beginning of this study. Given the comparability of results between the study groups, within our study, the postoperative complication rate and postoperative length of stay associated with Magtrace® were equivalent to the established gold standard technique using 99mTc. Section title: Discussion Educational score: 3.0544381141662598 Domain: biomedical Document type: Other Language: en The 99mTc-based tracer must be administered 3-24 hours preceding the procedure owing to its short half-life of <6 hours. Furthermore, the administration of this must take place within a nuclear medicine department. Careful coordination between the nuclear medicine department and operating department is essential, to ensure adequate 99mTc during the procedure. Section title: Discussion Educational score: 3.5312628746032715 Domain: biomedical Document type: Other Language: en SPIO-based tracers afford both clinician and patient flexibility, unlike the 99mTc-based tracer as Magtrace® can be administered on the operating table not only 20 minutes prior to the procedure but also up to 30 days prior to the procedure as licensed by the National Institute for Health and Care Excellence (NICE). This not only mitigates the unnecessary radiation exposure to the patient in the event of the cancellation of a procedure but allows for patients to have adequate time and flexibility prior to the procedure, unlike the restrictive timing necessitated by 99mTc-based tracer injection. Section title: Discussion Educational score: 2.9337103366851807 Domain: biomedical Document type: Study Language: en At our institution, 22 patients received the Magtrace® injection on the operating table. This obviated the need for the patient to come into the hospital prior to the procedure for the tracer injection. As a result, the increased operative time observed with the Magtrace® cohort may not be as significant as the pre-surgical procedure was not required. Furthermore, given that clinicians must wait 20 minutes after the administration of Magtrace® to start the procedure, this may explain the significantly longer operative time seen with the Magtrace® cohort. Section title: Discussion Educational score: 2.3154237270355225 Domain: biomedical Document type: Study Language: en The main limitation of this study is its small sample size and retrospective design. We believe that including a larger number of patients would enhance the significance of the findings. Section title: Conclusions Educational score: 4.0855512619018555 Domain: biomedical Document type: Study Language: en Our study demonstrates that Magtrace® can successfully be implemented in our institution and similar district general hospitals with outcomes equivalent to the current established gold standard practice of using 99mTc-based tracers to facilitate SLNB in breast cancer. Furthermore, not only were detection rates equivalent in the Magtrace® cohort, but postoperative length of stay and complication rates were similar in both groups as well. Therefore, Magtrace® can be feasibly and safely implemented in a district general setting with equivalent efficacy. | Review | biomedical | en | 0.999996 |
PMC11698379 | Section title: Introduction Educational score: 3.936569929122925 Domain: biomedical Document type: Other Language: en Erythrodermic psoriasis (EP) is a rare and severe form of psoriasis vulgaris, with a 1-2.25% prevalence among psoriatic patients . It is defined by considerable erythema that covers at least 80-90% of the body surface and is frequently associated with fever, chills, headache, and general discomfort . EP often mimics a burn-like appearance of the skin due to the intense inflammation, and the associated systemic symptoms can make it difficult to differentiate from other severe skin conditions. Section title: Introduction Educational score: 4.090505599975586 Domain: biomedical Document type: Other Language: en The onset might be abrupt or gradual and can be triggered by a range of factors, such as mental stress, infections, or new medications . The pathophysiology of EP requires additional research; however, certain immunological biomarkers, like interleukin-4, interleukin-10, IgE antibodies, and T-helper 2 lymphocytes, are suspected to be implicated. EP is a medical emergency because it disrupts the skin’s normal barrier functions, which are crucial for regulating body temperature, preventing infections, and maintaining fluid and electrolyte balance. The loss of these protective functions can lead to severe fluid loss, multiorgan failure, and an increased risk of infections. The management of EP can be very challenging, and if left untreated, the patient could be at risk of experiencing multi-system organ failure and high-output heart failure due to cutaneous volume loss . Section title: Introduction Educational score: 3.88838791847229 Domain: clinical Document type: Clinical case Language: en We present a case where EP is evident in a patient, serving as a manifestation of recent psychological stress on a background of multiple treatment failures. The extent of the disease in this report was measured using the Dermatology Life Quality Index (DLQI). DLQI is a questionnaire comprising 10 questions aimed at assessing the influence of skin conditions on an individual's quality of life. Each question receives a score between 0 and 3, resulting in a total score range from 0 (indicating no effect of the skin condition on quality of life) to 30 (suggesting the highest impact on quality of life) . Section title: Case presentation Educational score: 2.8583452701568604 Domain: clinical Document type: Clinical case Language: en A 76-year-old woman with poorly controlled psoriasis (DLQI 28) was referred to the medical expected unit after experiencing generalized weakness with limited movement, fever, tachycardia, leg swelling associated with pain and redness, decreased appetite, and a reduced level of consciousness. The patient had recently visited her general practitioner for leg cellulitis, for which she was given oral antibiotics that were ineffective. Section title: Case presentation Educational score: 2.2751009464263916 Domain: clinical Document type: Clinical case Language: en She has been struggling with psoriasis and psoriatic arthritis for about 30 years, for which she was under both dermatology and rheumatology specialists. She had tried various disease-modifying anti-rheumatic drugs, notably sulfasalazine, leflunomide, and cyclosporin, which provided marginal benefits. The patient is presently undergoing treatment with 25 milligrams (mg) of subcutaneous methotrexate administered weekly. Additionally, it has been observed that she recently experienced the loss of her daughter, an event that may have exerted a psychosocial impact on her. Section title: Case presentation Educational score: 3.8787310123443604 Domain: clinical Document type: Clinical case Language: en During the clinical assessment, psoriasis was observed to involve the entire body surface area, accompanied by a low-grade fever. The skin was warm to touch, dry, and thickened with prominent silvery-white scaling . Notably, there was substantial edema in the lower extremities with localized cellulitis, resulting in restricted mobility . In the hospital setting, the patient was initially treated with intravenous clindamycin at a dose of 600 mg four times daily for two days, after which therapy was switched to oral clindamycin, and the patient subsequently remained afebrile. Methotrexate was withheld while treating the acute infection, and the patient was started on adalimumab following a short course of intravenous hydrocortisone. The results of the blood tests during admission indicated an improvement in C-reactive protein and normalization of serum creatinine following fluid management (Table 1 ). Mild thrombophilia had also improved after discharge from the hospital, and neutrophilia was observed to be related to steroid initiation. Section title: Case presentation Educational score: 1.7673662900924683 Domain: clinical Document type: Clinical case Language: en The effectiveness of adalimumab was re-evaluated after a period of six weeks. Notable improvement in the skin symptoms was observed. Nevertheless, the patient continued to exhibit some visible signs of the disease, and hence, another assessment of adalimumab's efficacy will be conducted at 16 weeks. Section title: Case presentation Educational score: 0.9269686937332153 Domain: biomedical Document type: Other Language: en Photography Section title: Case presentation Educational score: 1.607897162437439 Domain: clinical Document type: Other Language: en Photography of this patient was quite restricted due to her condition and lack of mobility. However, with nursing help and patient compliance, a variety of different views were obtained to illustrate the condition. There was plenty of natural light available in the room, so an ISO (film speed) of 3200 was used with some additional fill-in-flash to enhance the texture and detail of the condition within the images . Section title: Discussion Educational score: 3.681910276412964 Domain: biomedical Document type: Other Language: en Psoriasis (psoriasis vulgaris) is a chronic (long-term) autoimmune condition characterized by extensive scaling caused by epidermal cell hyperproliferation. It typically presents with large oval-circular plaques over the scalp, trunk, and extensor body surface . More commonly, EP arises as a complication of psoriasis vulgaris . Section title: Discussion Educational score: 4.065632343292236 Domain: biomedical Document type: Study Language: en Although EP is classified as a subtype of psoriasis, the pathogenic processes are distinct from those seen in plaque psoriasis , IL36RN mutations have been linked to pustular psoriasis, and the class I antigens HLA-Cw6, HLA-B57, HLA-B13, and HLA-B17 have been linked to psoriasis vulgaris. However, very little is known about the genetic foundation of EP . Several studies suggest that the disease is associated with a predominantly T-helper 2 phenotype. Section title: Discussion Educational score: 3.682748794555664 Domain: clinical Document type: Clinical case Language: en In this report, the patient’s symptoms were classic EP, including widespread erythema, desquamation, and systemic involvement. Notably, the patient also developed cellulitis of the lower limbs . Given the severity of the infection, the cellulitis was treated with antibiotics to prevent further complications, such as sepsis, which can occur if left untreated. The co-occurrence of an infection with EP underscores the delicate nature of the skin’s integrity in this condition. Section title: Discussion Educational score: 2.638458490371704 Domain: biomedical Document type: Other Language: en A contributing factor to the relapse of EP in this patient might have been the psychological stress related to a significant life event that the patient described. Stress is well-known to trigger or exacerbate psoriasis by altering immune system activity and increasing inflammation. Section title: Discussion Educational score: 4.085594177246094 Domain: biomedical Document type: Study Language: en The mechanism by which psychological stress contributes to the onset or worsening of psoriasis is not yet fully understood. Psychological stress activates the hypothalamic-pituitary-adrenal axis, leading to the release of stress hormones (cortisol, adrenaline, and noradrenaline) that interfere with immune regulation and amplify inflammatory responses, fostering a pro-inflammatory environment . Although cortisol typically exerts anti-inflammatory effects, prolonged stress may diminish its regulatory capacity, allowing unopposed inflammatory pathways . Section title: Discussion Educational score: 4.189909934997559 Domain: biomedical Document type: Study Language: en EP, in particular, is propelled by an immune response dominated by T-cells, particularly Th1 and Th17 subsets, along with dendritic cells that produce potent pro-inflammatory cytokines such as IL-17, IL-22, TNF-α, and IFN-γ . Chronic stress further amplifies T-cell activation, significantly intensifying the immune response. This excessive cytokine production may result in a “cytokine storm,” a widespread and severe inflammatory reaction that manifests as extensive skin redness, scaling, and edema . Section title: Discussion Educational score: 3.9565889835357666 Domain: biomedical Document type: Study Language: en Additionally, EP compromises the skin’s barrier function, heightening the risk of infection and fluid loss. In cases triggered by stress, dysregulated cortisol levels may further undermine skin barrier integrity. Together with the high systemic inflammation, these factors render the skin highly susceptible to infections, while stress-related immune suppression increases the body’s vulnerability to opportunistic infections . Section title: Discussion Educational score: 3.9047441482543945 Domain: biomedical Document type: Review Language: en Nonpharmacological treatments, such as effective stress management techniques, mindfulness meditation, cognitive-behavioral therapy, relaxation techniques, and physical exercise, can help patients reduce their physiological stress response. In five out of six randomized control trials, participants demonstrated improvements in self-administered psoriasis area and severity index scores following eight or 12 weeks of meditation and/or mindfulness interventions. Additionally, two studies indicated psychological benefits for psoriasis patients after engaging in these practices. Collectively, these findings imply that meditation may serve as an effective method for enhancing both psoriasis severity and the quality of life for patients . Section title: Discussion Educational score: 4.0885491371154785 Domain: biomedical Document type: Other Language: en Pharmacological treatment usually includes oral hydration, topical steroids, vitamin D analogs, and a trial of biological therapy. In this instance, due to the severity of the condition and the risk of further systemic complications, the decision was made to initiate treatment with adalimumab, a TNF-alpha inhibitor. Adalimumab was chosen because of its potent anti-inflammatory properties, which specifically target the overactive immune response seen in psoriasis. It effectively neutralizes TNF activity by impeding its interaction with TNF receptors on the cell surface. This inhibition curtails the migration of leukocytes, subsequently reducing the proliferation and differentiation of keratinocytes . Section title: Discussion Educational score: 2.4599311351776123 Domain: biomedical Document type: Other Language: en In combination with adalimumab, the patient was also prescribed methotrexate, a well-known immunosuppressive medication that inhibits the rapid turnover of skin cells and reduces immune system activity. Methotrexate is often used alongside biologics to enhance treatment efficacy and to provide more comprehensive immune suppression. Section title: Conclusions Educational score: 4.045541286468506 Domain: biomedical Document type: Clinical case Language: en This case report represents a rare presentation of EP associated with psychological stress. When patients present critically ill with an erythrodermic rash, it is important to consider EP in the differential diagnosis, especially with recent psychological stress. The mechanisms through which psychological stress interferes with psoriasis onset or exacerbations are not completely understood. However, psychoneuroimmunology studies have shown that acute and chronic stress can affect immune function, leading to a worsening of psoriasis by inducing keratinocyte proliferation and incomplete maturation. | Other | biomedical | en | 0.999998 |
PMC11698405 | Section title: BACKGROUND Educational score: 3.8793296813964844 Domain: biomedical Document type: Other Language: en Visual methods represent a novel approach in qualitative evidence synthesis (QES) by introducing another dimension to the synthesis process and contributing to the understanding and generation of knowledge . The terminology “qualitative data or evidence” broadly refers to findings from primary qualitative studies (e.g., analysis of data from interviews, focus groups, and the production of new theories or theoretical insights), or qualitative data (such as narrative responses to open ended questions). Numerous methods can be used for data synthesis in a QES including meta‐ethnography , thematic synthesis , and framework synthesis . Irrespective of the method used for analysis and synthesis, additional visual methods can play a crucial role in aiding review authors and readers to comprehend, organize and display qualitative data collected from included studies . Section title: BACKGROUND Educational score: 4.019562721252441 Domain: biomedical Document type: Study Language: en There is a tendency for review authors to underutilize the diverse array of visual display methods, tools, and techniques available to enhance a chosen synthesis method . Some review authors may assume that their selected synthesis method includes all necessary supplementary methods, tools, and processes, while others may lack the skills or confidence to generate alternative formats for their synthesis. This paper provides an overview of accessible visual methods supporting the synthesis stages of a QES, with examples and their application in the development of a Cochrane QES using meta‐ethnography. The paper also addresses the role of stakeholders, considerations of equity, diversity, and inclusion, and reflexivity in selecting and employing additional visual methods. Although the focus is on QES, the visual methods described here can also be used to facilitate communication of complex and sensitive topics in primary qualitative research during data collection and analysis . Section title: Overview of visual methods and their uses Educational score: 2.41593861579895 Domain: other Document type: Other Language: en Table 1 presents an overview of visual methods according to their role in the synthesis process (i.e., support and develop synthesis, facilitate stakeholder engagement, and record the synthesis process). Visual methods can be used in different ways at various timepoints to support the synthesis of qualitative evidence, such as data display and management, initial exploration of data, and synthesis. Visual methods can help with the development of new insights from data allowing a deeper understanding and construction of new knowledge . Section title: Considerations when selecting a visual method to support the synthesis Educational score: 1.6850759983062744 Domain: biomedical Document type: Other Language: en Visual methods should be selected based on whether they can add value to facilitating the synthesis or be used as an integral part of the analytical process (e.g., use of diagrams to develop and visualize the synthesis). All of the visual methods listed in Table 1 are flexible and adaptable to different tasks and the creativity of the review team. Section title: Considerations when selecting a visual method to support the synthesis Educational score: 1.9640330076217651 Domain: other Document type: Other Language: en When selecting visual methods, it is important to first consider the content and objectives of the synthesis. The choice of method should align with the analytical goals, such as enhancing understanding or encouraging collaboration within the research team. For example, some visual methods may be more effective for developing early‐stage ideas, while others might help to present findings more clearly. Section title: Considerations when selecting a visual method to support the synthesis Educational score: 1.7046183347702026 Domain: other Document type: Other Language: en Delivery considerations, particularly when working remotely, also play a key role. Resources such as internet connectivity, relevant hardware (e.g., computers), and software (e.g., Microsoft Teams) are essential if implementing visual methods online. Remote working also demands technical knowledge from the research team. In addition, visual methods involving a group of researchers (whether in person or remotely) can involve high costs, preparation, and may require a facilitator. Practical considerations, such as preparing materials (e.g., paper labels) and developing a plan for how the method will be used, are crucial for group meetings. If using arts or performance‐based methods, the presence of artists or actors may be required. Section title: How to apply visual methods in qualitative evidence synthesis Educational score: 4.094588756561279 Domain: biomedical Document type: Review Language: en To illustrate the use of visual methods to support a synthesis, a worked example of a recent QES using meta‐ethnography is used . Meta‐ethnography is one of the most complex QES methods designed to synthesize mainly rich data from primary qualitative studies in a series of steps to develop new theoretical insights and theory . The review authors investigated how children and young people with chronic noncancer pain and their families experience and understand their condition, pain services and treatments . The whole team was involved in conducting the analytic synthesis with two members leading on and carrying out the majority ofthe analytic synthesis. They produced three lines of argument, a model and a theory of chronic pain management. The combination of their lines of argument was named “The journey of living with chronic pain” which expressed the experiences of children and young people with chronic pain and their families from the onset of chronic pain; their struggle to navigate health services seeking a cure, and to have their needs and expectations met; and the outcome, moving on either to prioritize living well with pain or give up hope . Section title: Stakeholder involvement and engagement Educational score: 2.4065744876861572 Domain: biomedical Document type: Review Language: en The review involved a diverse stakeholder group of health professionals, third sector organizations, policy makers, academics, and the public as well as a patient and public involvement (PPI) group of children and young people with chronic pain aged 8–20 years old and parents from across the United Kingdom. The PPI and stakeholder groups were involved throughout the entire review including making decisions about which studies to include in the synthesis and how to group studies in order to analyze and synthesize them, and the analysis and interpretation of findings from primary studies and of preliminary synthesis findings. Section title: Visual methods to display data Educational score: 2.956052303314209 Domain: biomedical Document type: Review Language: en France used a variety of visual data display methods at different stages of their meta‐ethnography to help convey the complex evidence and synthesis, especially to PPIs. The review authors worked mainly remotely as a dispersed team with few opportunities to meet face‐to‐face due to the COVID‐19 pandemic, hence they developed and delivered most of their visual methods virtually. In the absence of guidance on the selection of visual methods, the review authors drew on high‐quality relevant QES reports that used visual display methods successfully . Once the review team gained confidence and found that these visual methods were highly valuable, they selected visual methods to further enhance the synthesis process . Section title: Visual methods to display data Educational score: 1.7236409187316895 Domain: biomedical Document type: Study Language: en In the following sections, we discuss and evaluate the contribution of each method used in the meta‐ethnography. Section title: Paper labels Educational score: 4.122054576873779 Domain: biomedical Document type: Study Language: en This method was used among the review team only between phases 5 and 6 as part of the analytic synthesis process (to translate the studies into one another and in synthesizing translations). The review authors used paper labels to initiate the synthesis process and start developing novel insights . In a previous step, at least two review authors interpreted the meaning of every relevant finding, concept, or theme from the studies using NVivo version 12. The authors then compared the meanings within and across studies to identify common or unique concepts. Where possible, the common concepts were then matched, merged, and further interpreted by two review authors and discussed with the wider team of review authors to develop new interpretations. The common concepts and new interpretations were summarized on paper labels. Unlike NVivo 12 , paper labels provided the necessary visual and textual components needed to allow a larger number of researchers to work together during in‐person analysis. For instance, labels included a title and a short summary explaining the specific findings and contributing studies. All labels were color‐coded according to health condition and whose interpretation was presented (i.e., that of the primary study author or the review team). Paper labels were also numbered to match the structure of an accompanying detailed Word document which gave the full details of the primary study data underpinning the short summary of the findings. This strategy of visually displaying all findings helped the review authors to iteratively test different ways of thematically grouping the findings. It also helped to conduct a thematic analysis with the creation of new themes signposted using Post‐it notes. Photos were taken to record different versions (e.g., version 1, version 2, etc.) so that the review authors could follow the development of their analysis and subsequent synthesis. Section title: Paper labels Educational score: 1.3250107765197754 Domain: other Document type: Other Language: en The use of paper labels supported the development of new themes and an initial draft of thematic groupings. Labels helped the review authors to efficiently analyze a large volume of rich data and findings as a team. Paper labels enabled teamwork in the identification of overarching concepts and creation of new understandings or concepts during a synthesis meeting. Section title: Paper labels Educational score: 3.4069719314575195 Domain: biomedical Document type: Study Language: en When working remotely, the review authors adapted the method by recreating all paper labels virtually using Padlet , a real‐time collaborative web platform. Padlet virtual labels were color‐coded according to whose interpretation was presented (i.e., whether it was the interpretation of the primary study author or of the review team) and included a title and description of the construct. Both physical and virtual labels were used together during the team meeting. The idea was that members joining remotely via Microsoft Teams could participate in the thematic synthesis in real time using the virtual labels. However, the review authors learned that constantly updating Padlet to match the thematic groupings in real time was challenging and time‐consuming. This process could have been more efficient with the involvement of a dedicated facilitator, who could have taken responsibility for regularly updating the Padlet . As a result, the review authors that were joining the meeting online were updated verbally regarding the changes in the configurations of labels and Padlet was used only as a visual aid. At the end of the meeting, photos showing the labels that were used to create “new constructs” or understandings were uploaded on Padlet to facilitate discussion with the whole team and to provide a record of the analysis (Appendix S1 ). Section title: Interactive whiteboard—Google Jamboard Educational score: 3.854807138442993 Domain: biomedical Document type: Study Language: en A digital interactive whiteboard, Google Jamboard, was used during phase 6 of the meta‐ethnography to display data and develop analytic categories remotely . Google Jamboard is composed of different “frames,” similar to pages or slides. The authors used each frame to analyze a specific cluster of related themes, which were grouped together into a broader “analytic category,” for instance, as shown in the frame in Figure 4 . All findings were recreated as notes that were color‐coded according to the “analytic category” to which they belonged. All notes included a title, the contributing studies, the health condition, and whose interpretation was presented (i.e., that of the primary study authors or the review team). The “analytic categories,” themes, and their constituent findings and all notes were numbered to match the same structure as the textual synthesis (i.e., a Word document containing the full details of the primary study data underpinning the findings, themes, and analytic categories). This strategy allowed the authors to easily transfer any changes or new interpretations into the textual synthesis document. Google Jamboard also facilitated the tracking of how the themes were organized according to the different interpretations from the team and facilitated team discussions of the different interpretations. Section title: Interactive whiteboard—Google Jamboard Educational score: 1.7536154985427856 Domain: biomedical Document type: Other Language: en Using Google Jamboard to display the analytic categories, themes, and their constituent findings resulted in the creation of five analytic categories that organized the whole textual synthesis. This visual method was crucial to allow interactive online analytic synthesis meetings using all the different perspectives and expertise from the whole research team . Section title: Interactive whiteboard – Microsoft Whiteboard Educational score: 4.010222434997559 Domain: biomedical Document type: Study Language: en This method was used during phase 6 of the meta‐ethnography to visualize and further develop the synthesis. Microsoft Whiteboard is a multiplatform application which simulates a virtual whiteboard and enables real‐time collaboration. The review authors used Microsoft Whiteboard to express and understand how findings were connected to one another to create a coherent “storyline” [line of argument] (see Section 1.3 ). Initially, the authors included all themes under their respective category as text boxes on Whiteboard . All text boxes were color‐coded according to context (i.e., different colors were used to indicate starting points, potential links with other categories, and findings representing a positive impact). The authors used arrows to indicate which findings/themes were related, and the result was a large diagram linking all five categories (Appendix S2 ). Short descriptions for each analytic category were created based on the diagrams and these were discussed during an analysis meeting with the research team. At this point, the review authors focused on creating a better understanding of each analytic category. Subsequently, the diagram was further developed incorporating different interpretations and perceptions from the multidisciplinary team, resulting in major modifications to allow a more in‐depth exploration of these data (Appendix S3 ). Section title: Interactive whiteboard – Microsoft Whiteboard Educational score: 3.0590012073516846 Domain: biomedical Document type: Study Language: en At this stage, the visual representation of all analytic categories in the form of diagrams allowed the team to develop their understanding of and start developing the initial “overarching storylines” or lines of argument. The initial interpretations and hypotheses were inserted in the diagram as virtual notes. The final step was the creation of a further simplified version of the diagram that displayed how all four final analytic categories and findings were connected. The researchers used this last version of the diagram to further develop the description of the diagram to include how all categories and themes/findings were related which was used to create the textual synthesis. Section title: Interactive whiteboard – Microsoft Whiteboard Educational score: 1.2756792306900024 Domain: other Document type: Other Language: en Microsoft Whiteboard was used to develop the overarching storylines which culminated in the development of three lines of argument. This process also resulted in the development of four analytic categories and the initial textual synthesis. While the Whiteboard allowed real‐time collaboration and facilitated teamwork, it only worked well with the core research team of two people as it was hard for the wider team to keep track of or readily interpret the large and complex diagrams. Section title: Cartoons and infographic Educational score: 2.2668192386627197 Domain: biomedical Document type: Study Language: en Cartoons and an infographic were used during phase 6 (synthesizing translations) of the meta‐ethnography to engage stakeholders and further develop and clarify the synthesis findings. PPI was fundamental to help clarify ambiguous or unclear findings. The review authors delivered virtual workshops with parents and young people to discuss, clarify, and interpret preliminary findings of the synthesis. Storyboard was used to create cartoons to convey ambiguous and unclear findings to prompt discussion among the PPI members and a scenario was created for each cartoon to facilitate this process. Section title: Cartoons and infographic Educational score: 1.9668270349502563 Domain: biomedical Document type: Other Language: en The cartoons were representative, including people of different ethnicities and genders and the language used was accessible and engaging for children around 8–9 years of age. Patient and public members received the cartoons along with an infographic explaining the preliminary findings a week prior to the workshop. The use of cartoons and an infographic to engage PPI members in facilitated discussions on what some concepts and findings would mean to parents and young people, providing context and adding nuances based on lived experience to some of the findings. Subsequently, new data and insights were incorporated into the analytic synthesis and were used to further refine and develop the interpretation of findings. Section title: Diagrams to express the synthesis findings Educational score: 4.033414840698242 Domain: biomedical Document type: Study Language: en Diagrams were used by the review authors during phases 6 and 7 to further understand and express how the three lines of argument they developed were related. They used the final diagram they had produced using Microsoft Whiteboard , data from the PPI workshop, and the textual synthesis, to create an initial version of a visual model to refine and represent the findings of the synthesis connecting all lines of argument in Microsoft Word . The initial synthesis model was developed following feedback from the whole research team and depicted the nonlinear nature of the phenomenon of interest (i.e., families' journeys living with chronic pain and how they are affected by services). Subsequently, the researchers used Drawio to draw and refine the model with the inclusion of more context and nuance. This process of further refining the model consisted of rich interpretative discussions among the core members of the research team until an intuitive final version was constructed . The synthesis model expressed the concept of a journey families are navigating while they deal with chronic pain and access services. To express the concept of the journey and time, the researchers used rounded arrows to create an illusion of a cycle and described (text in red) where families might stay “stuck.” Two text boxes between both pathways indicated how families might navigate between these distinct pathways. Section title: Diagrams to express the synthesis findings Educational score: 1.4519578218460083 Domain: other Document type: Other Language: en The output was the final development and expression of the synthesis with a model produced initially in Microsoft Word and finalized in Drawio The model was fundamental to finalizing the synthesis, as it allowed remote teamwork and the incorporation of nuances and context provided during the PPI workshop. The model also enabled the expression of the overarching storyline connecting all lines of argument and the visualization of a complex nonlinear phenomenon. Section title: Diagrams to develop and express theory Educational score: 4.055095672607422 Domain: biomedical Document type: Study Language: en Diagrams were used during phases 6 and 7—synthesizing the translations and expressing the synthesis. The review authors produced a theory explaining their phenomenon of interest (i.e., theory of good chronic pain management). This process included multiple analysis meetings with the core review authors and it also integrated insights from PPI lived experience and the key findings from the synthesis of the studies included in the review data. The authors used two of their main analytic categories (related to family life and their social relationships and their experiences navigating health services) to construct the initial structure for the theory in the center of the diagram on Microsoft Whiteboard . The review authors then placed all factors that had a positive impact on family life on the right side of the diagram, and factors with a negative impact on the left side. They used arrows to indicate when an aspect could be modified by the factors placed on each side of the diagram. The final version of the diagram mapped all factors that had the potential to “modulate” families' experiences with chronic pain (Appendix S4 ). Figure 9 shows the simplified version of the diagram. Section title: Diagrams to develop and express theory Educational score: 2.6314969062805176 Domain: biomedical Document type: Study Language: en The factors that positively impacted family life and their experiences with services were then developed into actions in a whole systems biopsychosocial theory. This was achieved with further interpretation of the key findings (i.e., key outcomes families consider as important) while drawing from expertise from the research team and PPI lived experiences. The Drawio software was used to continue developing the theory, as it enabled clear visualization of the processes and facilitated discussions with the core research team. The final product expressed the whole system approach underpinning the theory through different background colors indicating different environments within the system . Section title: Diagrams to develop and express theory Educational score: 2.389612913131714 Domain: biomedical Document type: Other Language: en The output was the conceptualization and expression of a theory produced initially with MS Whiteboard and finalized in Drawio . The diagrams were fundamental to developing the theory as they allowed remote teamwork and the mapping of all factors modulating the phenomenon of interest. The expression of the theory through the diagram also allowed a clear visualization of gaps in the data, and where the evidence was based on lived experiences or on the research team's hypothesis. The use of the diagrams enabled complex analysis and supported the convergence of evidence from different sources into a detailed theory. More examples illustrating the use of diagrams in QES are available in Table 1 . Section title: DISCUSSION Educational score: 3.8139891624450684 Domain: biomedical Document type: Study Language: en We have shown that the use of additional visual methods in a QES facilitated better data visualization, remote analysis group meetings, interpretation of large amounts of data, and meaningful PPI during synthesis. Visual methods varied in complexity, costs, and required expertise, allowing flexibility to adapt to different contexts, whether virtual or face‐to‐face. For instance, certain methods such as paper labels worked better in face‐to‐face settings and facilitated group work involving multiple people. This method was essential to allow group work when dealing with large amounts of data. In contrast, the use of labels in virtual platforms such as Padlet was time‐consuming and demanded the presence of a facilitator and could only cope with moderate amounts of data. Section title: DISCUSSION Educational score: 1.4655475616455078 Domain: other Document type: Other Language: en Virtual platforms for implementing virtual methods remotely also worked differently depending on the task. For example, whilst Google Jamboard facilitated collaboration with the wider team as it was more accessible and interactive compared to the textual synthesis, it did not allow the analysis of a large amount of data. Each frame could only cope with one main analytic category and required a facilitator to enable discussion. In contrast, Microsoft Whiteboard allowed the processing of a large amount of data but only the collaboration of a small team of two people. Irrespectively, both methods allowed interactive online analytic synthesis meetings in different phases of the QES and were crucial for the development of findings. Section title: DISCUSSION Educational score: 3.1035540103912354 Domain: other Document type: Review Language: en It is imperative to carefully consider equity, inclusion, and diversity in the development and application of visual methods to ensure their accessibility and relevance across diverse populations. In addition, when developing and tailoring all virtual methods or outputs, the review authors need to carefully consider their personal biases and professional perspectives and positioning concerning what they would choose to present visually and how they interpret it. As such, it is essential that visualizations are either informed by or created with those they represent so they are inclusive and relatable to their audience. For example, in France's meta‐ethnography the authors co‐developed cartoons with members of the public and were careful to ensure these were representative of different ethnicities, and genders and did not promote an idealized context. The review authors also carefully considered the scenario and context of each cartoon ensuring these were appropriate and inclusive (e.g., a plain doctor's surgery and non‐descript hospital settings). Visual methods should also use accessible and engaging language and include accessibility features such as subtitles, image, and audio descriptions. Section title: CONCLUSIONS Educational score: 4.002470016479492 Domain: biomedical Document type: Study Language: en To the best of our knowledge, this is the first study to date showing the application of additional visual methods in a published QES. Visual methods are currently underused and underreported in QESs. QES authors should consider making use of available visual methods, particularly when involving members of the public during synthesis. Selecting the appropriate visual method for synthesis should be guided by its ability to enhance analysis and align with the study's objectives. Methods must suit the content and stage of synthesis, whether for idea development or presenting findings. Practical factors, including available resources and the team's technical skills, are crucial, especially for remote work. Additionally, group‐based methods may require significant preparation, facilitation, and specialized skills. Careful consideration of these aspects will ensure the effective and efficient use of visual methods. Section title: AUTHOR CONTRIBUTIONS Educational score: 0.9811396598815918 Domain: other Document type: Other Language: en Dr. Mayara Silveira Bianchim, Professor Emma France and Professor Jane Noyes all participated in conceptualization, data curation, formal analysis, investigation, methodology, project administration, resources, software, visualization, writing of original draft and review and editing. Section title: CONFLICT OF INTEREST STATEMENT Educational score: 0.871033251285553 Domain: other Document type: Other Language: en The authors declare no conflict of interest. Section title: PEER REVIEW Educational score: 1.0693377256393433 Domain: other Document type: Other Language: en The peer review history for this article is available at https://www.webofscience.com/api/gateway/wos/peer-review/10.1002/cesm.70009 . | Other | biomedical | en | 0.999997 |
PMC11698477 | Section title: Introduction Educational score: 2.315654754638672 Domain: biomedical Document type: Other Language: en Shark populations have been in decline worldwide due to the rapid growth of global fishing capacity coupled with high bycatch rates . In addition, sharks generally have life history characteristics ( e . g ., low fecundity, late age at maturity, and relatively slow growth rates) that constrain reproductive capacity and render them intrinsically sensitive to fishing mortality . Despite these concerns, recreational angling is a popular leisure activity worldwide with recreational landings of sharks in the United States exceeding commercial landings in recent years , furthering the need to better understand the impacts of non-lethal recreational fisheries interactions on shark populations. Section title: Introduction Educational score: 2.9927196502685547 Domain: biomedical Document type: Study Language: en Although the practice of catch-and-release fishing is advocated in recreational fisheries, questions remain about levels of post-release mortality as well as more cryptic sub-lethal effects on growth and fitness due to stress, injuries, and increased susceptibility to predation [ 9 – 12 ]. While some studies have examined the physiological stress caused by catch-and-release fishing on sharks using other fishing techniques ( e . g ., longlining or drumlining) [ 13 – 15 ], there have been comparatively fewer studies evaluating the physiological stress response of sharks to common recreational angling gears or methods . Section title: Introduction Educational score: 4.13266658782959 Domain: biomedical Document type: Study Language: en Unlike large-scale commercial fisheries, which typically take place at a greater distance from shore, recreational anglers often access coastal environments that are critical habitat for many fish species at multiple life stages and can be especially important for juveniles . While shallow waters may offer young teleost fishes and sharks protection from natural predators or access to coastal resources, proximity to land increases the probability of recreational fishing interactions and exposes them to capture stress during a critical life stage [ 19 – 21 ]. Additionally, species with nearshore distributions and strong site fidelity, like the nurse shark ( Ginglymostoma cirratum ), are more accessible to recreational anglers, including the probability of repeated captures, and in turn, are potentially more susceptible to angling-related impacts. Nurse sharks are a coastal species found in the eastern Pacific and western Atlantic Oceans with neonates and juveniles remaining close to shore in seagrass flats and mangrove islands . Tagging studies have revealed a high degree of site fidelity in adults, including long-term mating site fidelity , and particularly limited movement patterns compared to other shark species [ 22 – 23 , 25 ]. The Everglades National Park Creel survey reported that between 1972 and 2002, nurse sharks were the second most frequently caught species from sport fishing trips . Although nurse sharks are common in South Florida and are often encountered in recreational fisheries, and their population there is believed to be increasing, the western Atlantic population overall is listed as “Vulnerable” by the IUCN with a decreasing population trend due to ongoing fishing pressures, habitat degradation, and the impacts of climate change . Section title: Introduction Educational score: 4.115126609802246 Domain: biomedical Document type: Study Language: en As a resident, largely non-migratory species, the nurse shark is especially susceptible to exposure to repeated capture stress in frequently fished environments. A study by Hammerschlag et al. found nurse sharks in Biscayne Bay did not avoid urbanized areas, even during periods of higher human activity. Furthermore, Whitney et al. reported nurse sharks have the lowest mass and temperature-adjusted metabolic rate known for any shark species, and suggested they may incur a much higher relative metabolic cost of activity in switching from rest to movement compared to more active elasmobranch species. Perhaps as a result of these characteristics, nurse sharks exhibit a relatively passive “fight” during capture compared to other species . However, these studies captured adults and used commercial or scientific fishing methods that have relatively long standardized soak times. Therefore, they lack key data on how juveniles respond to capture and the behavioral and physiological responses that this species exhibits as a result of recreational angling methods . With a relatively high cost of movement and low metabolic rate, nurse sharks are energetically suited for, and perhaps dependent on, a minimally active lifestyle and may experience negative physiological consequences if forced to actively ‘fight’ on a line. Identification of these angling-related consequences and their impact is essential for the development of best management and conservation practices for this species as they are often captured by shore-based recreational anglers and they are commonly perceived as a robust shark species by both scientists and recreational anglers in South Florida . Section title: Introduction Educational score: 4.153318405151367 Domain: biomedical Document type: Study Language: en The purpose of this study was to collect data on the physiological stress response of juvenile nurse sharks ( Ginglymostoma cirratum ) to catch-and-release recreational angling and the potential influence of biotic and abiotic factors in shaping that response. Specifically, we sought to measure the physiological status of juvenile nurse sharks at multiple points in time during an active fight on hook and line. To assess these impacts, lactate, glucose, hematocrit and osmolality were measured, and the relationship between these parameters and fight time, shark size, and water temperature were evaluated. This is the first study to examine the physiological disturbance caused by recreational angling in nurse sharks and therefore provides information on a data limited species. Understanding these physiological impacts could have applications for species-specific management of recreational fisheries and better support conservation initiatives for nurse sharks. Section title: Study site, fishing and capture methods Educational score: 1.7309715747833252 Domain: other Document type: Study Language: en Sampling was conducted in Northern Biscayne Bay near Miami, Florida from November 2019 to October 2020 along shorelines with similar depths ranging from 3 to 9 feet. Biscayne Bay is a large, shallow marine estuary encompassing coral patch reefs, seagrass beds and mangrove shoreline. The Bay serves a significant ecological role, supporting substantial biodiversity . Biscayne Bay has experienced rapid urbanization due to human population growth over the course of the 20th century as it borders Miami-Dade County, Florida, a major U.S. county with a current population of approximately 2.67 million people . Urban land use change and anthropogenic pressure has resulted in habitat degradation, eutrophication, overfishing and localized die-offs of seagrasses, mangroves, and coral reefs . Section title: Study site, fishing and capture methods Educational score: 4.184782028198242 Domain: biomedical Document type: Study Language: en Sharks were captured via hook and line using 8-foot recreational rods equipped with 50 lb. test monofilament, a stainless steel leader, and size 13/0 barbed circle hooks to reduce the risk of foul hooking ( i . e ., hooking in any part of the body other than the jaw) and increase the probability of successful landing. The time was recorded from the first sign a shark was detected on the line until the initial blood sample was taken (“time 0”), based on the methods of Hoffmayer and Parsons . Once hooked, sharks were retrieved as quickly as possible (within 3 min) to allow for the best estimate of pre-disturbance blood parameters . After the initial blood sample, each shark remained on the hook-and-line and was returned to the water where it was angled for the additional time between blood samples. Between blood draws the sharks were continuously engaging in active swimming against the line and not allowed to rest. Over a period of 30 min, 4 small blood samples (2 ml each) were drawn from the caudal vein of each animal. After each blood sample, the shark was returned to the water and the fight continued with each subsequent blood sample taken with variable fight time intervals between sampling ( i . e ., randomized ordering of an interval of 5, 10, and 15 min between each sampling event to control for the influence of shark handling and the blood draw procedure; Table 1 ). During the final landing, the sharks were also rapidly measured (pre-caudal length, fork length, total length, and girth), sexed (visual survey of cloaca), and tagged with small, plastic Floy-brand spaghetti tags (individuals < 1 m) or NOAA cooperative tags (individuals > 1 m; S1 Dataset ). Lastly, small fin clip samples were collected to be used in future genetic studies, and surface water temperature was recorded. Section title: Blood draw and processing Educational score: 4.165793418884277 Domain: biomedical Document type: Study Language: en At each time interval, individuals were retrieved from the water and whole blood samples (<2 ml) were drawn with 18-gauge 3-inch needles within 1 min of landing the shark via caudal venipuncture. Lactate and glucose were immediately measured by adding approximately 10 μl of blood each to a glucose meter (Accu-Chek glucose meter; Roche Diagnostics, Basel, Switzerland) and to a lactate meter . The remainder of the blood was then added to blood collection tubes spray-coated with lithium heparin (BD Vacutainer® Heparin Tubes) and stored on ice until returning to the lab. Hematocrit was immediately determined upon returning to the lab through centrifugation (13,000 g x 5 min) of plain capillary tubes and visual measurement of the packed red blood cell volume (% Hct). The remainder of the heparinized blood was transferred into vials and spun via centrifugation (13,000 g x 5 min) for plasma extraction. Vials containing plasma were frozen at -20°C for later lab-based analysis using a Westcor Vapor Pressure Osmometer to measure osmolality. Section title: Statistical analyses Educational score: 4.124385356903076 Domain: biomedical Document type: Study Language: en Linear mixed models (LMM) were used to explore how total fight time (the total amount of time a shark has been on the line) and fight time (the amount of time the shark fought on the line between blood draws, i . e ., 5, 10, or 15 min) relate to physiological parameters (lactate, glucose, hematocrit and osmolality). Total length, sex, water temperature, and fishing site were also included in the analysis as covariates. To control for the influence of shark handling and the blood draw procedure, the order of the fight time intervals (5, 10, and 15 min) varied randomly. Additionally, two variations of the model were used for each physiological parameter. The first model for each physiological parameter explored total fight time while the second model included blood draw number as a variable to investigate the potential influence of the blood draw procedure on the model output while also investigating relationships between physiological parameters and fight time. A separate LMM was used to determine the relationship between initial levels of each physiological parameter and the time it took to obtain the initial blood sample. For all the models, a random intercept (shark ID number) was included to account for between-subject variation. The sum of squared residuals was calculated for each model. Relative effect sizes were computed following Cohen with d = 0.2 representing a small effect size, d = 0.5 a medium effect size, and d = 0.8 a large effect size. Individual models were run using the “lme4” and “EMAtools” packages in R version 3.6.3 and statistical significance was set a priori at p < 0.05 ( S2 Dataset ). Section title: Statistical analyses Educational score: 3.905210256576538 Domain: biomedical Document type: Study Language: en Based on Giesy , the Lactate Pro meter overestimates lactate concentrations, but in a predictable way. Therefore, all lactate concentrations were converted using a calculated adjustment curve equation (y = 1.79x – 0.08). There were no differences in statistical significance for the variables in either model between the original Lactate Pro values and the adjusted lactate concentrations. The Accu-Chek glucose meter has not been validated with laboratory analysis. Therefore, the data presented were not converted to laboratory-based values. Section title: Results Educational score: 4.116454601287842 Domain: biomedical Document type: Study Language: en Between November 2019 and October 2020, a total of 27 nurse sharks (15 females, 12 males), with a total length ranging from 63 to 153 cm (mean ± SD = 101.8 ± 25.0 cm), were caught and sampled ( Table 2 ). Four sharks were recaptured and resampled (31 total angling events) one of which was caught three separate times and another of which was recaptured one day after being caught for the first time. The remaining two sharks were recaptured after 14 days and assumed to be fully recovered; therefore, data from all capture events were pooled for analysis. Additionally, one shark was able to break free from the line before the final blood draw could be performed. This individual had a NOAA cooperative tag and total length was estimated based on previous capture data from seven months prior linked to the tag. It was found that sex had no significant (all p > 0.05) effect on the stress response across any physiological parameter, so it was excluded from the models. Water temperature at the time of capture ranged from 21.1 to 33.9°C (mean ± SD = 30.5 ± 3.4°C). Fishing site was found to only be significant for osmolality (all other p > 0.05), so it was excluded from the other physiological parameter models. Section title: Results Educational score: 4.116481304168701 Domain: biomedical Document type: Study Language: en All initial blood samples in this study were collected within 3 min (mean ± SD = 1.84 ± 1.02 min) with the exception of two of the largest sharks. There were no statistically significant relationships between initial levels of lactate, glucose, hematocrit or osmolality and the time (0.55 to 2.58 min for all other sharks, 4.25 and 5.33 min for the two largest sharks) it took to obtain the initial blood sample (Lactate: p = 0.195, Glucose: p = 0.297, Hematocrit: p = 0.469, Osmolality: p = 0.519). The average initial lactate value was 1.22 ± 0.64 mmol/L ( Table 3 ). Section title: Results Educational score: 4.184144020080566 Domain: biomedical Document type: Study Language: en Lactate increased by an average of 611% (6.7 ± 2.17 mmol/L) over the 30-min fight . Furthermore, the LMM established a significant linear relationship between lactate, total fight time, and temperature . When blood draw number was added as a variable, model results indicated that blood draw number, fight time, and temperature were all significantly related to lactate ( Table 4 ). Glucose values increased by 72% (2.2 ± 0.87 mmol/L) , but only significantly changed with blood draw number ( Table 4 ). Hematocrit decreased by 0.7 ± 1.9% on average over the 30-min fight . Model results indicated increasing total fight time and blood draw number were inversely related to hematocrit and total length was positively related to hematocrit values ( Table 4 ). Osmolality decreased by 1.2% (17.9 ± 196.8 mOsm/kg) over the 30-min fight time , but fishing location was the only variable to have a significant correlation to osmolality ( Table 4 ). Section title: Discussion Educational score: 4.19825553894043 Domain: biomedical Document type: Study Language: en The stress from a capture event elicits a complex physiological response in fish. Although this physiological response has been relatively well-studied for some elasmobranchs [ 15 , 42 – 44 ], little research has been done to understand this response in nurse sharks, and what is known focuses on adults and scientific fishing methods . Their strong site fidelity and low metabolic rates make them particularly susceptible to repeated captures at recreational fishing sites and chronic exposure to localized stressors . Indeed, in this study, a total of four angling events were of recaptured sharks, with one shark caught three separate times and one caught only one day after it was first captured. It has been well-documented in previous studies that other species of elasmobranchs use shallow, subtidal zones as refuges from predators, and it is likely that juvenile nurse sharks are using these fishing sites around shallow, highly impacted urban areas ( e . g ., areas near marinas and sea walls) for protection from predation . Recaptures in this study suggest they may be site attached with small home ranges, which is supported by existing literature on other species . For example, juvenile lemon sharks ( Negaprion brevirostris ) use subtidal mangrove habitat to decrease the likelihood of encounters with predators even under conditions of decreased habitat quality . Although nurse sharks appear to be generally more resilient to capture stress than many other species , their strong site fidelity increases the risk of repeated captures and subsequent physiological responses. This potential chronic stress has been shown in other species to suppress growth, reduce reproductive success, and limit foraging energy, and can lead to increased predation risk and reduced survival . Section title: Discussion Educational score: 4.180298805236816 Domain: biomedical Document type: Study Language: en The results of the LMM for lactate revealed a significant linear relationship with fight time, although this and other physiological studies have been unable to distinguish between the stress response to an initial hooking event and the response to the “fight”. The relationship between fight time and lactate is reflected in existing literature including for juvenile sand tiger sharks . Similarly, Gallagher et al. found lactate to be the sole blood parameter to be significantly affected by increased time on the line for several shark species. The increase in lactate over time indicates that the “fight” on the line caused a shift to anaerobic respiration, which resulted in the accumulation of lactate as a byproduct. The elevated lactate levels (6.7 mmol/L on average) measured after 30 min in this study are consistent with previous research on other species, and similar increases in lactate are known to have negative physiological effects . Therefore, lactate values can serve as a proxy for assessing the immediate condition or health of a shark . Fuller et al. found lactate was able to significantly predict a shark’s behavior upon release with higher lactate values corresponding to more sluggish behavior post-release. Higher lactate values were also significantly correlated with moribund shortfin mako , blue , and blacktip sharks . Although our study did not observe post-release behavior or record post-release mortality rates, the literature suggests the observed increases in lactate represent a considerable physiological cost that could impact short-term health, potentially rendering juveniles more susceptible to predation or disease. Section title: Discussion Educational score: 4.094738006591797 Domain: biomedical Document type: Study Language: en Nurse sharks have regularly exhibited low behavioral and physiological response to capture stress. For example, Jerome et al. found nurse sharks consistently had the lowest relative levels of physiological disturbance among studied species, including lactate levels and reflex impairment. Likewise, nurse sharks caught on longlines exhibited low-intensity exercise in response, with maximum lactate levels only reaching 3.25 mmol/L , compared to a maximum of 22.1 mmol/L in this study. However, previous studies reporting lower lactate results used commercial or scientific fishing methods ( e . g ., drumlines or longlines) where the nurse sharks are able to settle on the bottom for the duration of the soak time (1 hour). This is the first study to examine the effects of active recreational angling on nurse sharks, and the first to explore physiological stress in juvenile nurse sharks. Section title: Discussion Educational score: 4.219698905944824 Domain: biomedical Document type: Study Language: en A period of hyperglycemia is expected after stress or exhaustive exercise in fish as utilization of glucose mobilized through the stress response or depletion of hepatic glycogen stores is suggested to occur [ 55 – 57 ]. Manire et al. observed a substantial decrease in glucose for both bonnethead and bull sharks caught with gillnets. Conversely, significant increases in glucose levels were detected in both Atlantic sharpnose and blacktip sharks caught using hook-and-line . In this study, a weak relationship between glucose and fight time was measured. Results from the initial model showed a significant, positive relationship existed between glucose and total fight time for nurse sharks. However, in the final model, blood draw number was significant and fight time was nearly significant, which suggests juvenile nurse sharks may exhibit a more pronounced stress response from handling and air exposure than from short periods of exhaustive exercise. Longer periods of air exposure were found to increase blood-based disturbances and mortality rates in bonefish , and significantly disrupt physiological parameters in little skates ( Leucoraje erinacea ) with acute thermal stress exacerbating these impacts . Previous work on elasmobranchs has also documented no meaningful change in glucose as a result of capture stress . The combination of these results suggests changes in glucose values may be species-specific, a finding that is supported in the literature . It should be noted that the relationship and accuracy of the Accu-Chek glucose meter compared to values obtained with a colorimetric assay in the laboratory has not been validated for nurse sharks, due to insufficient laboratory data . Inconsistencies between values obtained by the glucose meter versus a colorimetric assay could explain why there is only a weak relationship between glucose and fight time. Further investigation is needed to understand the accuracy of the Accu-Chek glucose meter. Section title: Discussion Educational score: 4.151668548583984 Domain: biomedical Document type: Study Language: en Several previous studies have found that capture stress either causes significant increases in elasmobranch hematocrit values or no significant changes . Conversely, the final model for hematocrit in this study found blood draw number decreases hematocrit values. These lower hematocrit levels suggest that blood loss, potentially from the venipuncture site or hooking location, may result in hemodilution in small nurse sharks. This has been measured in other studies of elasmobranchs, and given that many studies engage in serial sampling including of small sharks , should be considered in analysis. Repeated blood sampling of Port Jackson sharks and gummy sharks resulted in a significant decrease in hematocrit values, suggesting that the decline in hematocrit over the serial blood sampling protocol used here was likely a consequence of repeated blood extraction . Similarly, Mohan et al. measured significantly reduced hematocrit levels with increased handling times in blacktip sharks that were not related to the physiological stress associated with a capture event, and hypothesized the decrease was due to blood loss. Section title: Discussion Educational score: 4.138659477233887 Domain: biomedical Document type: Study Language: en Capture stress can lead to disruption in the ability to osmoregulate in aquatic animals due to water shifting out of vascular compartments in response to increased intercellular lactate in the blood . This is consistent with recent data showing an increase in osmolality with fight time in blacktip sharks and Atlantic sharpnose sharks . Interestingly, there was no evidence of a significant difference in osmolality in juvenile nurse sharks due to fight time. Similar results were observed in another study on blacktip sharks . It is possible that the decrease in hematocrit, which in theory could also have resulted from plasma water moving into the circulation from the tissues, may have offset any increase in osmolality that occurred during the 30-min fight . Additionally, it may take longer than 30 min for the effects of capture stress on osmolality to be clearly detectable. Section title: Discussion Educational score: 4.173887252807617 Domain: biomedical Document type: Study Language: en It is well known that many shark nurseries are susceptible to environmental fluctuations in salinity due to their shallow, coastal nature . In this study, osmolality varied significantly by fishing site with lower osmolality levels corresponding to sharks caught at a location near water outflows from canals that affect the salinity of surrounding habitats. Therefore, for species that typically have high site fidelity, local abiotic conditions may matter and proximity of the stress event to an outflow could affect the capture stress response. Additionally, coastal locations like the fishing sites in this study provide essential habitat for many elasmobranch species but are subjected to various anthropogenic disturbances. Aquatic animals are exposed to pollutants via the delicate respiratory surface of the gills and these environmental toxins are known to impair overall fish health and cause both acute and chronic stress . Some studies have found that sharks residing in wastewater-impacted areas are exposed to and can accumulate measurable quantities of human pharmaceuticals . Furthermore, Rangel et al. found that juvenile nurse sharks sampled in highly impacted urban areas of Biscayne Bay in Miami had higher concentrations of plasma-saturated and bacterial fatty acids, suggesting they consumed lower-quality food resources than conspecifics in less urban-impacted areas. Therefore, these juvenile nurse sharks may already be under environmental stresses that could affect their long-term health and ability to respond physiologically to capture stress, which may pose a greater threat to these animals than previously believed. Additional research is needed to understand the relationship between environmental factors, especially in highly-human-impacted areas, and capture stress. Section title: Discussion Educational score: 3.9468486309051514 Domain: biomedical Document type: Study Language: en Although fishing effort for this study largely focused on the summer months, precluding concrete comparisons, the estimated Catch Per Unit Effort (CPUE) was approximately three times higher in this study in summer than in winter. This suggests juvenile nurse sharks may not be utilizing these popular fishing locations during the cooler months or may not be feeding as frequently, and therefore are likely caught less frequently during the winter months. In addition, model results revealed that higher lactate levels corresponded to warmer water temperatures; a relationship that has been previously noted for several other elasmobranch species . This indicates juvenile nurse sharks may experience increased capture stress during summer months when water temperatures are higher. Increased likelihood of being caught by recreational fishers and the amplified physiological response to capture during the summer months could represent a meaningful stressor to juvenile nurse sharks around South Florida, but this warrants additional research. Section title: Discussion Educational score: 4.174322605133057 Domain: biomedical Document type: Study Language: en This study suggests juvenile nurse sharks exhibit a greater physiological stress response when exposed to recreational angling than some other shark species or their adult counterparts captured using other fishing methods. This provides insight into nurse shark stress responses that was not previously available, which can help to inform age- and practice-specific management and conservation strategies around shore-based recreational fisheries. Furthermore, results revealed blood draw number to be significant for lactate, glucose, and hematocrit, suggesting that handling and air exposure can cause substantial physiological stress for juvenile nurse sharks. These results and others suggest air exposure and handling by recreational anglers should be limited whenever possible, in line with other findings from recreational fisheries for teleosts . Therefore, policy decisions should be centered around reducing fight time as well as handling and air exposure in order to moderate the physiological stress experienced by juvenile nurse sharks caught on hook-and-line. Future studies should assess the primary endocrine stress response to capture as well as additional physiological variables (e.g., fatty acids and electrolytes) to gain a better understanding of the entirety of the capture stress response. | Other | biomedical | en | 0.999995 |
PMC11698478 | Section title: Introduction Educational score: 3.8797683715820312 Domain: biomedical Document type: Review Language: en Anemia is one of the most commonly prevalent nutritional deficiency disorders globally. It is characterized by decreased hemoglobin (Hb) concentration in relation to age, sex, altitude, and smoking status. Anemia can result from physiological factors such as pregnancy or pathological factors like increased loss or decreased production of blood or its components . Globally, about half a billion women are anemic. In the developing world, such as in a low to middle-income country like India, anemia is a major public health issue . Alarmingly, the prevalence of anemia in children, adolescent girls, and pregnant women is in excess of 50.0%, according to the National Family Health Survey-5 (NFHS-5) . The prevalence is higher in rural areas compared to urban areas . Section title: Introduction Educational score: 3.492497205734253 Domain: biomedical Document type: Other Language: en Adolescence is a period of rapid growth and development characterized by major physiological and biochemical changes in the body. In terms of nutrient requirement, it is a phase of increased demand. In both adolescent girls and boys, increased iron uptake is required to meet a rapid growth spurt; also, in girls, further supply is required to compensate for menstrual blood loss. Worldwide, one in four individuals aged 10-24 years suffers from anemia, which amounts to 430 million individuals. India is considered a nation of youth, and it is home to 253 million adolescents, out of which 72 million were anemic in 2018. Uttar Pradesh has the largest adolescent population in India and has twice the number of anemia cases compared to other Indian states . Section title: Introduction Educational score: 4.002662658691406 Domain: biomedical Document type: Study Language: en According to WHO, anemia is defined as a Hb concentration of less than 13 g/dL in males (15 years and above) and less than 12 g/dL in non-pregnant females (15 years and above) . Anemia in adolescents may lead to decreased growth and productivity and low scholastic performance, and, in the long term, can cause cardiomegaly and left ventricular failure. Additionally, anemia also causes complications related to pregnancy and childbirth in young females. This study was planned to assess the prevalence of anemia in the adolescent age group, as well as to examine the association between the prevalence of anemia and the sex of the participants, and the role of deworming tablets in preventing anemia. Section title: Materials and methods Educational score: 3.872063636779785 Domain: biomedical Document type: Study Language: en A community-based cross-sectional study was conducted in a rural area of Meerut district from September to December 2023. The study population involved adolescent beneficiaries of the Anemia Mukt Bharat program in the Behsuma area. The inclusion criteria were as follows: all adolescent health beneficiaries of the Anemia Mukt Bharat program. Those not willing to participate or those suffering from any chronic debilitating illness were excluded from the study The sample size was calculated based on the following formula: N = \begin{document}\frac{Z^2_{\alpha/2} \times p \times q}{d^2}\end{document} ; based on the NFHS-5 data for the prevalence of anemia in Meerut district (45.1%), and at 7.5% absolute precision, the required sample size came out to be 170. Section title: Materials and methods Educational score: 2.315845251083374 Domain: biomedical Document type: Study Language: en A simple random sampling method was employed for data collection. Out of 31 rural primary health centers (PHC) in Meerut district, one PHC was randomly selected using the lottery method, which turned out to be PHC Behsuma. The first household adjacent to the PHC was selected using the pencil tip method, and then subsequent households towards the left of the first house were considered until the desired sample size was reached. Section title: Materials and methods Educational score: 3.5790412425994873 Domain: biomedical Document type: Study Language: en Data were collected using a pre-designed and pre-tested questionnaire (see Appendices). Consent and assent were obtained from the guardians and beneficiaries, respectively, after explaining the nature of the study. A capillary blood sample was taken after cleaning and drying the index or ring finger of the non-dominant hand. Hb estimation was performed using a True-Hb hemoglobinometer (Wrig Nanosystems, New Delhi, India). WHO classification of anemia was used to classify beneficiaries. Data were tabulated and analyzed using Microsoft Excel. Chi-square was used as the test of statistical significance, and a p-value less than 0.05 was considered significant. Ethical approval was obtained from the institutional ethical committee . Section title: Results Educational score: 3.0559399127960205 Domain: biomedical Document type: Study Language: en Out of the 170 respondents, 60 (35.3%) were males, while 110 (64.7%) were females. Of note, 102 (60.0%) of the total respondents were found to be anemic, while 68 (40.0%) were non-anemic. Among males, 27 (45.0%) were anemic, whereas among females, 75 (68.2%) had anemia, as shown in Table 1 . There was a significant association between the sex of the participant and the prevalence of anemia, as females were more anemic compared to males . Section title: Results Educational score: 3.986558675765991 Domain: biomedical Document type: Study Language: en Among anemic individuals, moderate anemia was the most common entity, affecting 69 (67.6%) participants, followed by mild anemia in 20 (19.6%) and severe anemia in 13 (12.8%) individuals. Amongst anemic males and females, moderate anemia was present in 14 (51.9%) and 55 (73.3%) participants, respectively. Mild and severe anemia was present in eight (29.6%) and five (18.5%) anemic males, and 12 (16.0%) and eight (10.7%) anemic females respectively. The association between the sex of the participant and the severity of anemia was not significant (p=0.123), as indicated in Table 2 . Section title: Results Educational score: 4.0338897705078125 Domain: biomedical Document type: Study Language: en Among the 170 participants, 110 (64.7%) had consumed deworming tablets in the last six months, while 60 (35.3%) had not. As shown in Table 3 , we observed a slightly lower prevalence of anemia (n=65, 59.1%) in participants who had consumed deworming tablets as compared to those who had not consumed deworming tablets (n=37, 61.6%). The findings were not significant (p=0.74). Among 102 anemic participants, 65 (63.7%) had consumed deworming tablets in the last six months, while 37 (36.3%) had not. Among anemic individuals who had consumed deworming tablets, mild, moderate, and severe anemia was present in 13 (20.0%), 45 (69.2%), and seven (10.8%), respectively; in anemic individuals who had not taken deworming tablets, seven (18.9%), 24 (64.9%) and six (16.2%) had mild, moderate, and severe anemia respectively. Although the findings were not significant (p>0.05), severe anemia was more common in those who had not consumed deworming tablets in the last six months, as demonstrated in Table 4 . Section title: Discussion Educational score: 4.057986259460449 Domain: biomedical Document type: Study Language: en The present study revealed the overall prevalence of anemia in the adolescent age group to be 102 (60.0%), which is slightly higher compared to NFHS-5 data for rural areas of Uttar Pradesh. This study has shown a higher prevalence of anemia among females (n=75, 68.2%) compared to males (n=27, 45.0%). There was a significant association between the sex of the participant and the prevalence of anemia (p<0.05). Similarly, NFHS-5 data for rural areas of Uttar Pradesh revealed a higher prevalence of anemia in non-pregnant females (15-49 years), i.e., 50.7% as compared to males (15-19 years), in whom the prevalence of anemia was 29.9%. Kishore et al.'s study conducted in Rishikesh (Uttarakhand) showed that the overall prevalence of anemia was 53.2%, out of which 45.1% were males and 54.6% were females. The increased prevalence of anemia in females can be due to increased physiological demand, menstrual blood loss, poor eating habits in females, as well as social neglect. Section title: Discussion Educational score: 4.0650835037231445 Domain: biomedical Document type: Study Language: en In the present study, moderate anemia was the most common type, affecting 69 (67.6%) of the anemic individuals, whereas mild and severe anemia was present in 20 (19.6%) and 13 (12.8%), respectively. Similar findings were reported by Bajaj et al. from Pune, Maharashtra, where moderate anemia was the most prevalent form, affecting 55.0% of the study participants. This was followed by mild anemia at 40.7% and severe anemia at 4.3%. Among anemic males, mild, moderate, and severe anemia was present in eight (29.6%), 14 (51.9%), and five (18.5%), respectively; among anemic females, the prevalence was 12 (16.1%), 55 (73.3%), and eight (10.7%) respectively. Moderate anemia was more common in females, while mild and severe anemia was common in males. Kishore et al. reported that moderate and severe anemia were more common in females than males, whereas mild anemia was common in males. The reason for this prevalence of moderate and mild anemia could be that moderate anemia can go unnoticed for long periods with nonspecific symptoms like weakness and fatigue while severe anemia causes more pronounced symptoms like dyspnea on slight exertion or even at rest and hence is treated promptly in clinical settings. Section title: Discussion Educational score: 4.062599182128906 Domain: biomedical Document type: Study Language: en In this study, 110 (64.7%) children had consumed deworming tablets in the last six months and they exhibited a slightly lower prevalence of anemia: (n=65, 59.1%) as compared to those who had not consumed (n=37, 61.6%). However, the difference was not statistically significant (p>0.05). This shows that deworming alone is not effective in anemia prevention. The most probable reasons for ineffective deworming could be low nutritional intake, increased iron demand in the adolescent age group, recurrent worm infestations in rural settings, and poor service utilization. Scott et al. reported that 25.8% of children in their study had consumed deworming tablets in the last six months and that deworming tablets are an effective intervention in anemia prevention in southern India (OR: 1.77). Section title: Discussion Educational score: 3.9182703495025635 Domain: biomedical Document type: Study Language: en Kamble et al. reported that anemia prevalence among adolescent girls who received albendazole tablets for deworming on National Deworming Day was significantly lower as compared to those who did not undergo deworming (p<0.001). Alamneh et al.'s study from Ethiopia among different age groups (children aged 6-59 months) reported that deworming was effective in reducing moderate anemia by 21.0%, but its effect on mild and severe anemia was not significant. Severe anemia was reported in a lower proportion of participants (n=7, 10.8%) who had a history of deworming in the last six months compared to those who had not undergone deworming (n=6, 16.2%), although the difference was not significant (p>0.05). There is a paucity of research on the effects of deworming in reducing the severity of anemia. Section title: Discussion Educational score: 1.7324336767196655 Domain: biomedical Document type: Other Language: en Limitations of the study Section title: Discussion Educational score: 2.1419966220855713 Domain: biomedical Document type: Study Language: en This study has a few limitations. Primarily, it had a relatively smaller sample size, which may make generalizing the results to the broader population challenging. Moreover, calibrating and recalibrating the instruments may have affected the results - a lower proportion of the male population in the study. Section title: Conclusions Educational score: 4.068218231201172 Domain: biomedical Document type: Study Language: en The present study included adolescent beneficiaries (aged 10-19 years) of the Anemia Mukt Bharat program in a rural area of Meerut, Uttar Pradesh. About two-thirds of the study population were females. More than half of the study participants were anemic, and anemia was significantly higher in females compared to males. This can be attributed to increased menstrual blood loss, selective food habits among females, and, perhaps, ignorance due to gender discrimination. Among anemic participants, more than two-thirds were moderately anemic. The association between deworming and the prevalence of anemia was not significant. Among the anemic population, severe anemia was more common in those who had not consumed deworming tablets, but the results were not significant. Deworming alone can neither effectively prevent anemia nor decrease its severity significantly. Dietary patterns, nutritional deficiencies, vitamin C supplementation, and other non-nutritional causes of anemia need to be addressed promptly and extensively. | Review | biomedical | en | 0.999999 |
PMC11698479 | Section title: Introduction Educational score: 3.987257480621338 Domain: biomedical Document type: Review Language: en Diabetes mellitus (DM) is a chronic endocrine disorder caused by insulin deficiency or resistance. Insulin is a hormone produced by β-cells in the pancreas that helps maintain normal blood glucose levels . A large portion of the world's population is affected by diabetes and its associated complications. Dental problems should not be ignored in patients with DM. Poor oral health can be a major barrier to maintaining normal blood glucose levels in diabetic patients. DM is a metabolic disorder with long-term complications, often accompanied by comorbidities such as obesity, hypertension, cardiovascular problems, and renal diseases. Emergencies such as cardiac failure, cerebrovascular disease, pneumonia, and infections are common among diabetic patients and can be fatal if left untreated. Dental practitioners can assist in diagnosing DM based on early oral symptoms. Preventative measures to control metabolic health and maintain oral health pave the way for a healthier lifestyle. Therefore, dental practitioners play a significant role in improving the quality of life for diabetic patients . Section title: Introduction Educational score: 3.9645750522613525 Domain: biomedical Document type: Other Language: en According to a World Health Organization (WHO) report, more than 400 million people are affected by this chronic disease, with global prevalence increasing each year. Diabetes has become a major cause of blindness, kidney failure, heart attacks, stroke, and lower limb amputation. In 2016, it was identified as the seventh leading cause of death by the WHO . Consequently, dental patients with DM require comprehensive care to avoid disruptions in metabolic homeostasis. Both diagnosed and undiagnosed diabetic patients may seek various dental treatments. Proper precautions are essential while treating diabetic patients to avoid life-threatening risks . Therefore, clinicians must have a thorough understanding of the symptoms and management strategies for diabetes to minimize the risks associated with dental treatment . Additionally, patients need to be educated on diabetes-related oral health issues and the importance of maintaining oral hygiene through preventative care routines to minimize dental complications . Section title: Introduction Educational score: 2.385042905807495 Domain: biomedical Document type: Study Language: en A thorough understanding of diabetes and proper management of diabetic patients in dental clinics is crucial. Hence, this study aims to evaluate the knowledge and attitudes of Jouf University’s dental students and interns regarding diabetic patient management in dental clinics. Section title: Materials and methods Educational score: 1.753111720085144 Domain: biomedical Document type: Study Language: en Study design and setting Section title: Materials and methods Educational score: 3.815308094024658 Domain: biomedical Document type: Study Language: en A quantitative study was conducted at the College of Dentistry, Jouf University, involving dental students from the third to fifth year and interns working in the clinical setting. A self-reported survey was used to assess the knowledge and attitudes of these participants regarding the management of diabetic patients in dental clinics. The survey instrument was developed based on validated tools and relevant literature in diabetes management within dental settings to ensure content validity. Expert input from faculty members specializing in diabetes management and dental education was incorporated to finalize the survey questions. To refine the instrument further, a pilot test was conducted with a small subset of dental students and interns. Section title: Materials and methods Educational score: 2.058962106704712 Domain: biomedical Document type: Study Language: en Data collection took place between 15 March 2022 and 02 May 2022, with participants who voluntarily provided informed consent included in the study. Those who did not consent failed to complete the questionnaire, or did not provide basic demographic information were excluded. To minimize potential biases, anonymity and confidentiality were assured during the consent-taking process, encouraging honest and accurate responses. Section title: Materials and methods Educational score: 1.8246489763259888 Domain: biomedical Document type: Other Language: it Sample size calculation Section title: Materials and methods Educational score: 2.2650716304779053 Domain: biomedical Document type: Study Language: en The sample size was calculated based on the formula for finite population: Section title: Materials and methods Educational score: 1.7111064195632935 Domain: biomedical Document type: Other Language: ca \[ n = \frac{NX}{X + (N - 1)} \] Section title: Materials and methods Educational score: 2.0949718952178955 Domain: biomedical Document type: Other Language: en \[ X = \frac{\left(\frac{Z_{\alpha/2}}{2}\right)^2 p(1-p)}{(MOE)^2} \] Section title: Materials and methods Educational score: 3.2133145332336426 Domain: biomedical Document type: Study Language: en Also, Zα/2 is the critical value of the normal distribution at α/2 (for a confidence level of 95%, α is 0.05, and the critical value is 1.96), MOE is the margin of error (5%), and p is the sample proportion (50%). Section title: Materials and methods Educational score: 2.1603636741638184 Domain: biomedical Document type: Study Language: en No published study on this topic was identified from the extensive review of the literature in the KSA, covering the entire healthcare system. Therefore, the research team took the expected proportion (p) as 50% to get the maximum sample size. N is the population size, which is the total number of students and interns in the Jouf University dental training center = 160. Section title: Materials and methods Educational score: 1.2947086095809937 Domain: biomedical Document type: Other Language: en Therefore, Section title: Materials and methods Educational score: 2.029661178588867 Domain: biomedical Document type: Other Language: ca \[ X = \frac{(1.96)^2 (0.5)(1 - 0.5)}{(0.05)^2} = 385.6 \] Section title: Materials and methods Educational score: 1.7578520774841309 Domain: biomedical Document type: Other Language: cy \[ n = \frac{(160)(385.6)}{544} = 113 \] Section title: Materials and methods Educational score: 1.0735617876052856 Domain: biomedical Document type: Other Language: en Data collection Section title: Materials and methods Educational score: 2.4713540077209473 Domain: biomedical Document type: Study Language: en Data collection for this study was carried out using a customized and pretested questionnaire. The study comprised two main sections. The first section gathered demographic data, including age, gender, and educational level, from participants, while the second section focused on assessing their knowledge and attitudes through a structured set of questions. This included queries about their prior participation in educational programs related to the management of diabetic patients in dental clinics. Section title: Materials and methods Educational score: 2.055760145187378 Domain: biomedical Document type: Study Language: en Participants were approached in person within the clinical setting of the College of Dentistry, Jouf University. Each participant received a detailed informed consent form that outlined the purpose, objectives, and significance of the study, emphasizing the importance of understanding and improving the management of diabetic patients in dental care. Participants were informed that their role would involve completing a questionnaire based on their experiences, attitudes, and knowledge, with no additional follow-up commitments. Participation was entirely voluntary. Section title: Materials and methods Educational score: 1.5728188753128052 Domain: biomedical Document type: Other Language: en The informed consent form assured participants that no identifying information would be collected or disclosed. Personal data, including names or other personal details, were neither requested nor recorded. All data collected would remain anonymous and confidential, with no identifying information being published or shared. Participants were explicitly instructed not to write their names or any identifying information on the questionnaire. Section title: Materials and methods Educational score: 2.1844911575317383 Domain: biomedical Document type: Study Language: en The questionnaires were distributed in person in hardcopy format. After completion, male and female students from each academic year were asked to submit their completed forms to the designated leader of their respective level. The completed forms were then collected and submitted by the group leader. This method ensured an organized collection process while maintaining anonymity and preserving the integrity of participant responses. All responses were handled confidentially to protect the privacy of all participants. A shared Google spreadsheet (Google LLC, Mountain View, CA, USA) was then used to simplify the process of data entry and collaboration among researchers. To ensure data integrity and minimize the risk of unauthorized edits, each section of the spreadsheet was restricted to specific researchers assigned to that section. Permissions were managed to allow editing only by the designated researcher, while other team members had view-only access to those sections. This approach ensured data accuracy and accountability throughout the data management process. Section title: Materials and methods Educational score: 1.0534944534301758 Domain: other Document type: Other Language: en Ethical consideration Section title: Materials and methods Educational score: 1.3056696653366089 Domain: biomedical Document type: Other Language: en The Local Committee on Bioethics approved the study design and data collection at Jouf University (approval number: 3-05-43) on 10 March 2022. All participants were aware of the study objectives to ensure complete privacy and confidentiality. In addition, participants were advised that they could withdraw from the study at any time without consequences. Section title: Materials and methods Educational score: 1.4600969552993774 Domain: biomedical Document type: Other Language: en Statistical analysis Section title: Materials and methods Educational score: 3.5600619316101074 Domain: biomedical Document type: Study Language: en The Microsoft Excel data (Microsoft Corporation, Redmond, WA, USA) collected from the Google spreadsheet was exported to SPSS Statistics version 21 and encoded. Initially, a Wilk-Shapiro test was performed to assess the normality assumption of the collected data. A skewed distribution was observed, and non-parametric tests, Spearman's test, Mann-Whitney test, and Kruskal-Wallis test were performed based on the independent variables considered for the study. A p-value of <0.05 was considered statistically significant. Section title: Results Educational score: 1.6632226705551147 Domain: biomedical Document type: Study Language: en Demographic characteristics of the participants Section title: Results Educational score: 2.0600759983062744 Domain: biomedical Document type: Study Language: en Based on the population (p=160) considered, 113 participants' responses were sufficient to validate the study. However, we received 133 responses, all of which met the inclusion criteria and were included for evaluation. Table 1 describes the demographic data of the participants, while Figure 1 and Figure 2 illustrate the knowledge and attitude categories in this study. Section title: Results Educational score: 1.8098424673080444 Domain: biomedical Document type: Study Language: en Association between background details and knowledge score Section title: Results Educational score: 2.0749752521514893 Domain: biomedical Document type: Study Language: en The age and gender of the participants did not influence the knowledge score. However, the study level of the participants showed a significant difference. Fifth-year dental students exhibited maximum knowledge scores (Table 2 ). Section title: Results Educational score: 1.57291841506958 Domain: biomedical Document type: Study Language: en Association between background details and attitude score Section title: Results Educational score: 2.0463240146636963 Domain: biomedical Document type: Study Language: en The attitude scores differed significantly based on the gender and study level of the participants. Male participants exhibited better attitudes compared to female participants. Similarly, a comparable trend in knowledge scores was observed for attitudes regarding the variable of study level. The maximum positive attitude was observed among fifth-year dental students (Table 3 ). Section title: Results Educational score: 2.0459415912628174 Domain: biomedical Document type: Study Language: en Analysis between knowledge and attitude toward diabetic patient management Section title: Results Educational score: 3.8348517417907715 Domain: biomedical Document type: Study Language: en A significant positive correlation was observed between the knowledge and attitude of the dental students (Table 4 ). As knowledge increased, attitudes also improved. The open-ended inquiries revealed participants' knowledge and attitudes toward diabetic patient management techniques. Most participants suggested scheduling early appointments, while a few recommended providing proper counseling before treatment to alleviate diabetic patients' anxiety about dental procedures. Additionally, participants were aware of the possible complications associated with diabetic patients during dental treatment, including the risks of syncope, hypoglycemia, and hyperglycemia. However, most considered delayed healing to be an immediate complication during dental treatment. Section title: Results Educational score: 3.450594663619995 Domain: biomedical Document type: Other Language: en Most importantly, many students were unaware of how to manage medical emergencies involving diabetic patients during dental treatment. However, those who had previously attended educational programs on diabetic patient management provided appropriate responses. They suggested stopping dental treatment if symptoms of hypoglycaemic shock occurred. They also recommended checking the blood glucose level and administering fast-acting carbohydrates if necessary to prevent further complications. If the patient was unconscious or had difficulty swallowing or breathing, they advised seeking immediate medical attention and administering subcutaneous glucagon. Section title: Discussion Educational score: 3.9355361461639404 Domain: biomedical Document type: Study Language: en Oral health problems, such as periodontal diseases, dental caries, and xerostomia, are common in people with uncontrolled or poorly controlled diabetes. Diabetes and periodontal disease have a bidirectional relationship: periodontal disease can worsen glycemic control, and poorly managed diabetes can lead to periodontitis. Additionally, uncontrolled diabetes and certain medications used for diabetes management can cause xerostomia by impairing the normal function of the salivary glands. Elevated blood glucose levels also increase glucose in the saliva, creating an environment that promotes microbial accumulation and biofilm formation on the tooth surface, thereby increasing the risk of dental caries and gum disease. Therefore, it is essential to educate diabetic patients on maintaining oral hygiene. Dental practitioners should have a thorough understanding of diabetes-related oral health problems and risk factors . A study conducted among future dentists at Jouf University, Saudi Arabia, observed a positive correlation between knowledge and attitude toward diabetic patient management. Similar results were found in studies among oral health professionals in Australia and India . Section title: Discussion Educational score: 4.099958419799805 Domain: biomedical Document type: Study Language: en As shown in Table 1 , participants' age, gender, and level of education were considered to assess their knowledge and attitudes toward diabetic patient management in dental clinics. Age and gender differences did not affect participants' knowledge. However, academic level showed a significant variation in the knowledge score, with interns having lower knowledge compared to other study groups (Table 2 ). This may be due to the structure of the dental curriculum, where medical courses are integrated in the initial years to build a strong foundation for understanding diabetes and its systemic implications. Additionally, problem-based learning sessions are incorporated to enhance the application of knowledge in clinical contexts. As students progress, particularly in the later years, the focus shifts toward dental specialties, which may reduce the emphasis on medical subjects. In the fifth year, the "Problem Solving in Dentistry" course specifically addresses the management of medically compromised patients, reinforcing both practical and theoretical knowledge relevant to dental practice. These findings align with those of Komerik et al., who reported that dental students showed negative enthusiasm toward learning medical subjects in their curriculum. The dental students in their study felt that certain course content, including aspects of the human body unrelated to dentistry, was unnecessary and that they quickly forgot this information . Section title: Discussion Educational score: 4.074615478515625 Domain: biomedical Document type: Study Language: en Furthermore, attitudes toward managing diabetic dental patients varied based on gender and academic level. As shown in Figure 3 , males displayed more positive attitudes than females despite there being no significant difference in knowledge. This difference may be attributed to higher levels of confidence in managing diabetic patients, which could result from prior exposure to and participation in workshops specifically focused on diabetic patient management. These workshops likely provided them with a stronger foundation of both knowledge and practical experience, enhancing their comfort levels and promoting a more proactive approach to patient care. A similar trend in knowledge scores was observed for attitudes based on academic level . The least positive attitude was observed among interns (Table 3 ), which is consistent with Mussalo et al.'s findings. They reported that students' interest in biomedical sciences declined as they progressed through their dental program and entered the clinical phase . The current study supports these findings, confirming that positive attitudes toward managing patients in clinical settings are closely linked to both knowledge and confidence levels . Section title: Discussion Educational score: 4.103395462036133 Domain: biomedical Document type: Study Language: en The responses related to participants' knowledge and attitudes highlighted the need for educational programs on diabetic patient management for dental students. Although some participants demonstrated basic knowledge of diabetes, most were unaware of the proper management of diabetic emergencies during dental treatment. Clinicians must be efficient in managing hypoglycemic shock, which is associated with symptoms such as confusion, shakiness, tremors, agitation, anxiety, sweating, dizziness, tachycardia, a feeling of impending doom, seizures, and loss of consciousness . If any of these symptoms arise, it is advisable to stop dental treatment immediately. Administering 15 grams of rapid-acting carbohydrates is recommended to prevent further complications. Additionally, monitoring glucose levels is essential to determine if the patient requires further treatment. If the patient is unconscious or has difficulty swallowing or breathing, immediate medical attention should be sought, and glucagon should be administered subcutaneously . The participants in the current study were not confident in recognizing hypoglycemic shock symptoms and indicated that they would seek advice from supervisors, reflecting their anxiety about managing such patients in the dental clinic. However, students who had attended a previous workshop on diabetic patient management showed a more positive attitude toward managing medical emergencies. Section title: Discussion Educational score: 3.932978391647339 Domain: biomedical Document type: Study Language: en The participants in this study represent the future of dental practice. Therefore, the findings suggest that special training in diabetic patient management should be provided to dental students during their internship years. To build on these findings, it is recommended to integrate hands-on workshops, role-playing scenarios, and practical resources such as clinical posters or digital guides into the dental curriculum to strengthen the application of skills. Additionally, conducting regular evaluations, including periodic surveys, can help assess retention and ensure the ongoing effectiveness of the training. This would help dental graduates recall the basic medical knowledge learned in the early years of their graduate programs and apply that knowledge in practice. Section title: Discussion Educational score: 1.7324336767196655 Domain: biomedical Document type: Other Language: en Limitations of the study Section title: Discussion Educational score: 2.6880290508270264 Domain: biomedical Document type: Study Language: en The study's findings may not be generalizable beyond Jouf University due to differences in educational structures. Participants' knowledge and attitudes were potentially influenced by recall bias and varied prior training experiences. Specifically, differences in prior educational opportunities were evident, as some students attended workshops on diabetic patient management, potentially skewing the results toward more positive attitudes among those with additional exposure. Furthermore, a study involving a larger, more diverse population is recommended to enhance the generalisability of the findings. Section title: Conclusions Educational score: 4.051247596740723 Domain: biomedical Document type: Study Language: en The study found that education level significantly influenced dental students' knowledge and attitudes toward managing diabetic patients, with fifth-year students performing better than interns. Gender differences impacted attitudes, though knowledge remained unaffected, while age showed no influence on either. A positive correlation between knowledge and attitude was observed, particularly among students with prior training. These findings highlight the need for specialized training, interactive workshops, regular assessments, and resources like posters to enhance students' confidence and preparedness in managing diabetic patients. | Review | biomedical | en | 0.999996 |
PMC11698481 | Section title: Introduction Educational score: 4.502194404602051 Domain: biomedical Document type: Review Language: en Hemosuccus pancreaticus (HP) is a rare yet recognized cause of upper gastrointestinal (GI) bleeding, with delayed diagnosis often contributing to significant mortality . Chronic pancreatitis is the most common risk factor (60-65% of cases), while less common causes include peripancreatic arterial pseudoaneurysms (10-20%), pancreatic pseudocysts (10-20%), and acute pancreatitis (5-10%) . The pathophysiology of HP involves chronic enzymatic autodigestion of peripancreatic vessels, which leads to aneurysmal formation and rupture, resulting in bleeding through the pancreatic duct . Rupture often involves major peripancreatic arteries, including the splenic, pancreaticoduodenal, and gastroduodenal arteries . Notably, HP accounts for only 1 in 1,500 cases of upper gastrointestinal bleeds . In most cases, bleeding is usually intermittent and presents as abdominal pain, GI bleeding, and anemia, but severe cases can cause hemorrhagic shock and rapid bleeding into the duodenum, with mortality rates around 10%, higher in males (7:1 ratio) . Section title: Introduction Educational score: 4.011247158050537 Domain: biomedical Document type: Other Language: en Diagnosis is challenging due to coexisting conditions common in GI bleeding, such as cirrhosis, critical illness, and alcohol use . Despite the low index of suspicion for HP due to its rarity, HP should be considered in individuals with pancreatic disease and unexplained or recurrent GI bleeding . Acute GI hemorrhage should prompt suspicion for HP in cases with peripancreatic arterial pseudoaneurysms, pancreatic hematomas, or acute necrotizing pancreatitis, with alcohol use adding further complexity given its overlap with other etiologies of upper GI bleeding . Section title: Introduction Educational score: 3.9323601722717285 Domain: clinical Document type: Clinical case Language: en We present a case of HP and hemorrhagic shock in a 34-year-old with acute necrotizing pancreatitis and decompensated alcoholic cirrhosis. Initially, the patient presented with altered mental status and melena. Computed tomography (CT) angiography revealed a pancreatic tail hematoma and pancreatic head calcification, without evidence of aneurysm or necrosis. After several days, further imaging revealed a peripancreatic pseudoaneurysm and enlarging pancreatic tail hematoma amid acute onset necrotizing pancreatitis. Esophagogastroduodenoscopy (EGD) showed large clots and bleeding through the ampullary duct, leading to hemorrhagic shock and a worsening prognosis. Section title: Introduction Educational score: 3.9788365364074707 Domain: clinical Document type: Clinical case Language: en This case highlights HP as a severe complication of acute necrotizing pancreatitis, demonstrating the diagnostic challenges in patients with cirrhosis and GI bleeding, as well as the importance of a multidisciplinary approach in managing HP-associated hemorrhagic shock. The case also addresses the prognostic implications in patients with pancreatitis-related vascular complications, particularly in those with end-stage liver disease. Section title: Case presentation Educational score: 3.878774881362915 Domain: clinical Document type: Clinical case Language: en A 34-year-old male with a history of alcoholic cirrhosis (MELD 3.0 score of 30) presented after being found unconscious following heavy alcohol use, along with intermittent episodes of melena. The initial laboratory evaluation revealed elevated aspartate aminotransferase (AST), alanine transaminase (ALT), and total bilirubin with associated leukocytosis, normocytic anemia, elevated lipase, lactic acidosis, and acute kidney injury. On exam, he had encephalopathy, jaundice, scleral icterus, and mild, non-tender abdominal distention. A CT angiogram of the abdomen revealed a 6.2 cm hematoma anterior to the pancreatic tail, extending into the splenic hilum and abutting the greater curvature of the stomach, along with possible pancreatitis and splenic vein thrombosis . Section title: Case presentation Educational score: 3.8400940895080566 Domain: clinical Document type: Clinical case Language: en He required multiple packed red blood cell (pRBC) transfusions for suspected ongoing GI bleeding and treatment for alcohol withdrawal. Initial EGD demonstrated LA grade D esophagitis, no esophageal varices, mild portal hypertensive gastropathy, and mild extrinsic compression of the greater gastric curvature from the hematoma. Magnetic resonance cholangiopancreatography (MRCP) revealed a 6.9 cm pancreatic tail mass with possible pancreatic duct dilation. A follow-up CT confirmed a 6.5 cm pancreatic tail hematoma, an 18 mm splenic artery pseudoaneurysm, nonocclusive splenic vein thrombosis, and suspicion of necrotizing pancreatitis. Antibiotics were initially withheld due to the absence of signs of active infection. Section title: Case presentation Educational score: 3.8343918323516846 Domain: clinical Document type: Clinical case Language: en A repeat CT on day 13 of hospitalization confirmed necrotizing pancreatitis, an enlarged 2.5 cm splenic artery pseudoaneurysm, and a significantly increased pancreatic tail hematoma (10 cm x 19 cm x 13 cm) . The patient developed worsening ascites, confirmed as portal hypertensive ascites without spontaneous bacterial peritonitis (SBP), followed by an episode of hematochezia. Urgent CT angiography showed no active extravasation but noted a stable lesser sac hematoma and persistence of splenic artery pseudoaneurysm. Section title: Case presentation Educational score: 3.032503843307495 Domain: clinical Document type: Clinical case Language: en On day 18 of hospitalization, during preparation for a colonoscopy, the patient developed fever, tachycardia, and hypotension, requiring intensive care unit (ICU) transfer and vasopressor support. He was started on vancomycin and piperacillin-tazobactam for suspected septic shock secondary to necrotizing pancreatitis, alongside hemorrhagic shock from GI bleeding. Section title: Case presentation Educational score: 3.713960886001587 Domain: clinical Document type: Clinical case Language: en Repeat EGD revealed a small distal esophageal varix, moderate portal hypertensive gastropathy, and blood with clots in the duodenum. A side-viewing duodenoscope revealed a large clot extruding from the ampulla of Vater, consistent with HP . Compression of the greater curvature of the stomach by the expanding pancreatic tail hematoma was also noted. Section title: Case presentation Educational score: 3.830848455429077 Domain: clinical Document type: Clinical case Language: en Interventional radiology (IR) was consulted and diagnostic angiography was performed on the peripancreatic vasculature, identifying a pseudoaneurysm involving an unnamed pancreatic perforator artery from the splenic artery, anastomosed with the pancreatica magna artery. Initial attempts to embolize were unsuccessful due to prominent arterial spasms; however, a repeat attempt showed active arterial extravasation seen from a small pancreatic arterial branch that was successfully treated with coil embolization . Section title: Case presentation Educational score: 3.1983675956726074 Domain: clinical Document type: Clinical case Language: en The antibiotic regimen was escalated to meropenem for three days for suspected ongoing infection. Despite the resolution of septic and hemorrhagic shock, persistent hematochezia necessitated near-daily pRBC transfusions. A repeat CT angiography revealed a 7 mm residual pseudoaneurysm. IR advised against repeat angiography or embolization due to the development of multiple aneurysms. General surgery was consulted, and he was deemed a poor surgical candidate due to his decompensated cirrhosis. Given the patient's deterioration and risks of complications, a goals-of-care discussion held with the patient and family led to the decision to not escalate medical care. Section title: Case presentation Educational score: 2.159677267074585 Domain: clinical Document type: Clinical case Language: en The patient’s hematochezia and hepatic encephalopathy worsened. Therapeutic paracentesis was performed for comfort due to worsening ascites. A few days later, he developed severe shock, likely secondary to acute GI bleeding, along with profound hypoxia with altered mental status. The patient's family at this time elected for comfort care measures, and he passed away shortly thereafter. Section title: Discussion Educational score: 4.037622451782227 Domain: clinical Document type: Clinical case Language: en This case presents a unique presentation of HP secondary to acute necrotizing pancreatitis, resulting in hemorrhagic shock in a patient with decompensated cirrhosis. HP with coexisting cirrhosis is exceptionally rare, with only a few reports documenting this combination . In a retrospective study at a single center, only 1 out of 17 patients treated for HP had cirrhosis . Most documented cases attribute intermittent GI bleeding in HP to a pseudoaneurysm from chronic pancreatitis, with rare instances of severe bleeding or hemorrhagic shock . Section title: Discussion Educational score: 4.04539680480957 Domain: clinical Document type: Clinical case Language: en Notably, no previous reports associate HP with acute necrotizing pancreatitis, making this case significant as the first to link HP, severe hemorrhagic shock, and death with end-stage liver disease. Our patient’s severity was compounded by a pancreatic pseudocyst, arterial pseudoaneurysm, and a pancreatic tail hematoma, emphasizing the complexity of managing HP in patients with cirrhosis, where treatment options are often limited. This case contributes to the growing literature on HP, emphasizing the need to promptly recognize and manage comorbidities to enable timely diagnosis and intervention, potentially preventing fatal outcomes. Section title: Discussion Educational score: 3.275468111038208 Domain: biomedical Document type: Other Language: en Pathophysiological links between hemosuccus pancreaticus, cirrhosis, and acute necrotizing pancreatitis Section title: Discussion Educational score: 4.318819522857666 Domain: biomedical Document type: Clinical case Language: en In this case, the patient’s decompensated cirrhosis (MELD 30, Child Pugh C) significantly worsened the prognosis, as cirrhosis-mediated portal hypertension and coagulopathy amplified the risk of severe hemorrhage . In cirrhosis, elevated pressures in the portal venous system, including the splenic and mesenteric veins, drive collateral formation, indirectly promoting the formation of pseudoaneurysms . Splenic vein congestion or thrombosis increases stress on local vasculature, including the splenic artery . Splenomegaly, resulting from venous congestion, places extrinsic pressure on the splenic artery, raising the likelihood of aneurysms, as shown in studies linking enlargement of the splenic vein with splenic artery aneurysm . Chronic elevation in portal pressure, leading to the formation of collateral circulation, further increases hemodynamic demand on the arterial system. This compensatory hyperdynamic circulation places increased strain on arterial walls, resulting in localized vessel weakening and dilation . Section title: Discussion Educational score: 4.053837776184082 Domain: biomedical Document type: Study Language: en Cirrhosis-associated coagulopathy also worsened the patient’s condition, as impaired clotting factor synthesis, vitamin K deficiency, and platelet sequestration from splenomegaly elevated the risk of bleeding . Overactive fibrinolytic pathways, in addition to vessel fragility, increase susceptibility to severe hemorrhage in acute necrotizing pancreatitis . Section title: Discussion Educational score: 4.1169753074646 Domain: biomedical Document type: Clinical case Language: en Vascular involvement occurs early in acute pancreatitis in up to 25% of cases, increasing to 43% of cases in necrotizing pancreatitis, manifesting as venous phlebitis, arteritis, venous thrombosis, or pseudoaneurysms . Hemorrhage occurs in 3-6% of necrotizing pancreatitis cases, with over half due to pseudoaneurysmal rupture . In this case, we propose that acute necrotizing pancreatitis triggered a rupture in a pancreatic arterial branch of the splenic artery, leading to hemorrhagic via HP. Bleeding typically occurs in the retroperitoneum, but in cases like this, blood may flow through the pancreatic duct into the gastrointestinal tract . Section title: Discussion Educational score: 4.328126907348633 Domain: biomedical Document type: Study Language: en Necrotizing pancreatitis results in HP through mechanisms such as vascular erosion, tissue necrosis, and pseudocyst formation . Pancreatic enzymes induce autodigestion, eroding vessels and promoting pseudoaneurysms, which develop in approximately 4% of necrotizing pancreatitis cases, with a mortality of up to 14% . The splenic artery is most affected (38%), followed by the gastroduodenal and pancreaticoduodenal arteries . Pancreatic tissue necrosis compromises the integrity of surrounding vasculature, facilitating hemorrhage in the acute setting . Pancreatic pseudocysts may also exacerbate HP by compressing and rupturing nearby vessels, where compromised vasculature leads to rapid GI hemorrhage . Section title: Discussion Educational score: 1.9307482242584229 Domain: biomedical Document type: Other Language: en Diagnosis and treatment of hemosuccus pancreaticus Section title: Discussion Educational score: 3.900357961654663 Domain: biomedical Document type: Review Language: en HP is a challenging diagnosis due to its anatomic complexity and poor visualization of the pancreaticobiliary system during endoscopy . Intermittent bleeding further complicates detection, as endoscopy may fail to detect HP if active bleeding is absent . Studies report that upper endoscopy identifies HP in only ~30% of cases, with improved success using a side-viewing duodenoscope for ampulla visualization . Negative endoscopy does not rule out HP, as other causes of bleeding like hemobilia and ampullary tumors remain in the differential diagnosis . Section title: Discussion Educational score: 3.9726099967956543 Domain: clinical Document type: Clinical case Language: en In our case, the initial EGD demonstrated esophagitis and portal hypertensive gastropathy, without ampullary bleeding. Subsequent imaging revealed a pseudoaneurysm and an enlarging pancreatic tail hematoma, leading to repeat endoscopy and observation of clots protruding from the ampulla using a side-viewing duodenoscope. Diagnosis often requires multi-modal imaging, with contrast-enhanced CT used to detect pseudoaneurysms, pseudocysts, and extravasation . Angiography of peri-pancreatic vessels enables both diagnosis and treatment through embolization . Section title: Discussion Educational score: 3.9607338905334473 Domain: biomedical Document type: Other Language: en Angiographic embolization is currently the first-line treatment for HP from pseudoaneurysmal bleeds and has seen technical success rates of 97%, with long-term success rates around 82-88% . Technological advances have improved outcomes considerably over the past decade . In cases of concurrent cirrhosis, the management of HP is multidisciplinary, requiring collaboration amongst gastroenterology, interventional radiology, surgery, and critical care physicians. For initial stabilization, crystalloid fluids, blood transfusions, and vasopressors are crucial for achieving hemodynamic stability until definitive intervention is performed . Section title: Discussion Educational score: 3.5584685802459717 Domain: biomedical Document type: Other Language: en In cirrhotic patients, management includes coagulopathy correction using vitamin K, fresh frozen plasma (FFP), and platelets . Vasoactive agents such as octreotide or terlipressin reduce portal pressure, alleviating strain on collateral vessels, while antibiotics prevent bacterial translocation and spontaneous bacterial peritonitis . Section title: Discussion Educational score: 4.033961296081543 Domain: biomedical Document type: Other Language: en When coil embolization is unsuccessful, surgical hemostasis may be necessary to prevent exsanguination, with procedural options including distal or central pancreatectomy, splenectomy, or aneurysm ligation, depending on the bleeding location . However, in cirrhotic patients with high Child-Pugh scores, surgical intervention has high operative mortality, especially in patients with Class C cirrhosis (up to 80%) . For this patient, distal pancreatectomy might have been an option if embolization had failed but was contraindicated due to advanced cirrhosis . Effective long-term management, which includes nutritional support, pancreatic enzyme replacement, and management of pancreatic pseudocysts or vascular abnormalities, remains critical for improving patient outcomes and long-term survival. Section title: Discussion Educational score: 1.8166067600250244 Domain: biomedical Document type: Other Language: en Recent advancements in treatment and the role of endoscopic ultrasound Section title: Discussion Educational score: 3.986260414123535 Domain: biomedical Document type: Review Language: en Recent advancements in endoscopic technology have highlighted the utility of contrast-enhanced endoscopic ultrasound (EUS) for diagnosing and managing HP. EUS, particularly with contrast enhancement, provides a detailed view of vascular structures surrounding the pancreas, allowing for precise localization of pseudoaneurysms responsible for bleeding . While non-contrast EUS is valuable in delineating pancreatic anatomy, it lacks the sensitivity needed to identify small, bleeding culprit vessels within the pancreatic tissue . Contrast enhancement overcomes this limitation, making EUS a suitable option even for patients with renal impairment, as it avoids nephrotoxic contrast agents used in CT angiography. Section title: Discussion Educational score: 3.9438130855560303 Domain: clinical Document type: Clinical case Language: en A recent case report describes successful EUS-guided treatment in two cases of HP using cyanoacrylate injection into the pseudoaneurysm, resulting in hemostasis and no recurrence over follow-up periods of three and six months . This outcome highlights the potential role of EUS not only for diagnosis but also as a minimally invasive therapeutic intervention. Although underreported, EUS-guided management of HP may emerge as a critical intervention for managing pseudoaneurysmal bleeding in HP, particularly when traditional imaging and treatments pose greater risks or fail to control bleeding effectively. Section title: Conclusions Educational score: 3.9210731983184814 Domain: biomedical Document type: Review Language: en To summarize, acute necrotizing pancreatitis can lead to severe vascular complications, including pseudoaneurysmal rupture, ultimately resulting in HP. The mortality associated with pseudoaneurysmal rupture is high in cases of massive hemorrhage and hypovolemic shock. In patients with decompensated cirrhosis, underlying coagulopathy and hemodynamic changes exacerbate bleeding and further worsen outcomes. Section title: Conclusions Educational score: 3.933336019515991 Domain: biomedical Document type: Other Language: en Therefore, early identification and intervention through endovascular coiling or surgical intervention is paramount for survival, alongside fluid resuscitation, and blood transfusion. While coil embolization remains the gold standard for endovascular intervention, newer therapies such as contrast-enhanced endoscopic ultrasound (EUS) are emerging as promising diagnostic and therapeutic tools. Ultimately, a multidisciplinary approach is essential for improving outcomes, particularly in navigating complex cases. | Review | biomedical | en | 0.999994 |
PMC11698532 | Section title: Introduction Educational score: 4.044600486755371 Domain: biomedical Document type: Review Language: en Glioblastoma is the most common primary malignant brain tumor, accounting for 48.6% of all malignant central nervous system tumors . Despite advancements in treatment over the past two decades, patient outcomes remain dismal, with a median overall survival (OS) of only 15 months following initial diagnosis . The standard treatment for glioblastoma includes maximal safe resection followed by radiotherapy with concomitant temozolomide . Typically, external beam radiotherapy (EBRT) is administered five days a week over six weeks, delivering a total dose of 60 Gy in 30 fractions. However, even with aggressive adjuvant chemoradiotherapy, tumor recurrence is nearly universal. Salvage treatment options for recurrent disease remain limited, with bevacizumab being the primary standard option. Section title: Introduction Educational score: 3.872502088546753 Domain: biomedical Document type: Other Language: en Approximately 85% of recurrences occur within the margins of the prior resection cavity , making intracavitary adjuvant brachytherapy an attractive strategy. This approach offers potential advantages, including the immediate initiation of radiation therapy, the elimination of multiple visits required for EBRT, and intensified radiation delivery to areas most prone to disease progression. Section title: Introduction Educational score: 4.010859489440918 Domain: biomedical Document type: Study Language: en Intracranial brachytherapy has been previously investigated using iodine-125 (I-125), but it was associated with high rates of adverse radiation effects (14-33%), likely due to I-125’s long half-life of 59.4 days . GammaTile ® (GT) brachytherapy, incorporating Cesium-131 (Cs-131), may provide a better therapeutic ratio due to Cs-131’s shorter half-life of 9.7 days and higher dose rate of 0.342 Gy/hr . GT received FDA approval in 2018 for recurrent brain tumors and in 2020 for newly diagnosed malignant brain tumors . Section title: Introduction Educational score: 4.093890190124512 Domain: biomedical Document type: Study Language: en GT utilizes a bioresorbable collagen matrix embedded with four Cs-131 seeds. This design allows for precise dosimetry and delivers 88% of the therapeutic dose (80-120 Gy to the first few millimeters from the implantation site) within 30 days, and over 95% within six weeks (equivalent to four half-lives of Cs-131), during which the collagen matrix fully dissolves . This fixed-seed configuration offers more predictable radiation distribution compared to the earlier “loose-seed” implantation methods. Section title: Introduction Educational score: 3.603142499923706 Domain: biomedical Document type: Study Language: en While GT appears to reduce the incidence of adverse radiation effects , its impact on improving progression-free survival and OS in recurrent glioblastoma patients remains an active area of investigation. Furthermore, survival outcomes in patients treated with repeat brachytherapy are rarely reported in the literature. Section title: Introduction Educational score: 3.488640308380127 Domain: clinical Document type: Clinical case Language: en This report presents a case of two separate GT implantations in the management of multiple recurrent glioblastoma. The patient achieved more than three years of survival from the initial diagnosis while maintaining good functional status, without evident treatment-related toxicity or surgical wound complications. Section title: Case presentation Educational score: 3.912017583847046 Domain: clinical Document type: Clinical case Language: en The patient was a 62-year-old right-handed male who presented to the emergency department of an outside hospital with several weeks of worsening headaches and gait instability. MRI with and without contrast revealed a large right temporal mass accompanied by significant vasogenic edema . During that hospital admission in November 2020, the patient underwent partial resection of the mass with Gliadel wafer implantation. Histopathological analysis of the tumor sample confirmed a high-grade glioma consistent with glioblastoma, characterized as IDH-wild type, MGMT-unmethylated, and BRAF V600E-mutated. Following the resection, the patient received standard-of-care treatment at our institution, consisting of temozolomide chemotherapy (140 mg) in combination with radiation therapy (60 Gy in 30 fractions). Section title: Case presentation Educational score: 3.7164089679718018 Domain: clinical Document type: Clinical case Language: en Four months after the initial resection and following one cycle of pembrolizumab, the patient presented with blurry vision, and MRI confirmed tumor recurrence . Given his relatively good performance status, the patient was offered and underwent repeat resection, with placement of seven GTs and a prescribed dose of 60 Gy to a depth of 0.5 cm. Postoperative MRI showed near-total resection of the previously noted enhancing lesion. Representative dosimetric images are presented in Figure 5 . Section title: Case presentation Educational score: 3.6164703369140625 Domain: clinical Document type: Clinical case Language: en The patient was discharged home a few days later without postoperative complications or the need for steroids. Final surgical pathology confirmed a diagnosis of recurrent glioblastoma. However, three days after discharge, the patient returned to the emergency department with low-grade fevers and fatigue. A CT head was negative for acute findings. The patient was discharged with symptomatic management and presented to the clinic three days later with persistent fevers, mild headache, and neck pain. Lumbar puncture revealed a normal opening pressure, but elevated protein and white blood cell count (total nucleated cells of 1,159 per µL, with normal percentages of neutrophils and lymphocytes) and decreased glucose. A diagnosis of aseptic meningitis was made, and the patient was treated with dexamethasone, resulting in symptomatic improvement. The patient subsequently restarted temozolomide at a dose of 380 mg daily. Section title: Case presentation Educational score: 4.073762893676758 Domain: clinical Document type: Clinical case Language: en The patient’s clinical status and surveillance MRIs remained stable until December 2022 (25 months following the initial resection), during which time temozolomide had been discontinued. The patient then reported a new left-sided peripheral visual field deficit, and MRI findings were consistent with tumor progression. A third resection was performed, followed by a second GT implantation involving eight tiles, with a prescribed dose of 60 Gy to a depth of 0.5 cm. A cumulative dose, including external beam treatment and the two GT implants, was calculated in the treatment planning system. The optic apparatus (both nerves and chiasm) received a maximum point dose of 81 Gy, with a 0.1 cc dose of 74 Gy. The brainstem received a maximum point dose of 141 Gy, and the doses of 0.1 cc, 1 cc, and 10 cc were 133 Gy, 114 Gy, and 49 Gy, respectively. These accumulated doses represent algebraic sums, with no correction for biologically equivalent doses. Section title: Case presentation Educational score: 1.894836664199829 Domain: clinical Document type: Clinical case Language: en Surgical pathology was consistent with a recurrent tumor admixed with radiation necrosis. The patient was discharged home two days later without complications and reported visual improvement during a follow-up clinic visit two days after discharge. Section title: Case presentation Educational score: 3.5622661113739014 Domain: clinical Document type: Clinical case Language: en Vemurafenib was initially started but discontinued shortly afterward due to poor tolerance and negative BRAF V600E testing on the updated surgical specimen. The patient was then started on bevacizumab and lomustine approximately three months following his third resection. The patient was later hospitalized for a perforated colon and entered a period of observation, during which chemotherapy treatment was paused. A surveillance MRI in December 2023 (37 months following the initial resection) showed enhancement along the posterior wall and right ventricular margin of the prior resection cavity . At the time of the last follow-up in our clinic, the patient had a good neurological status but elected to enter hospice care in January 2024 due to his refusal to undergo further abdominal surgery. Section title: Discussion Educational score: 3.8477487564086914 Domain: biomedical Document type: Clinical case Language: en The use of brachytherapy in glioblastoma patients presents a potential alternative or complement to existing therapeutic approaches, such as EBRT and radiosurgery, particularly in cases of recurrent disease. To our knowledge, this report represents the first published case of a patient treated with two separate GT implants. The patient survived for 10 months following the second brachytherapy treatment and approximately 37 months from the initial diagnosis. Section title: Discussion Educational score: 3.8855478763580322 Domain: biomedical Document type: Study Language: en Brachytherapy has an established role in the treatment of other malignancies, such as cervical, uterine, and prostate cancers, among others . However, its effectiveness in treating intracranial neoplasms remains less clear. Two prior randomized controlled trials did not show significant survival benefits when I-125 implants were combined with EBRT or with EBRT and carmustine in patients with high-grade glioma. These trials were conducted before the routine use of neuronavigation to aid in achieving gross-total resection and before the widespread use of sensitizing chemotherapy . Additionally, there may be advantages to using Cesium-containing GT compared to traditional iodine-based seeds, given its higher dose rates and more predictable dosimetry. Section title: Discussion Educational score: 4.078672409057617 Domain: biomedical Document type: Study Language: en While GT has shown promise in treating recurrent meningiomas and metastatic brain tumors , its use in glioblastoma cases is less well documented. In a study of 22 patients with IDH-wild type recurrent glioblastoma treated with GT, the median OS for the treatment group was 24.4 months, compared to 17 months in the control group who did not receive GT implantation . Importantly, the study reported no differences in length of hospital stay or postoperative complication rates between the two groups . Another report involving 20 patients with recurrent glioblastoma found the median post-recurrence OS to be nine months for those treated with Cs-131, with no cases of radiation necrosis in patients treated concurrently with bevacizumab . However, it is important to recognize that the patients eligible for intensified therapy may have had clinical characteristics that predisposed them to improved survival, and thus, selection bias must be considered when interpreting these results. Ongoing trials are expected to provide further insight into the role of GT in the treatment of newly diagnosed and recurrent glioblastoma. Two randomized trials, the GammaTile and Stupp in Newly Diagnosed GBM (GESTALT) trial and NCT04427384, are currently enrolling patients. Section title: Discussion Educational score: 3.901343584060669 Domain: biomedical Document type: Clinical case Language: en The eventual clinical decline of our patient was likely multifactorial, including the challenges of multiple recurrences requiring repeat resections and other health complications, which ultimately led to the family’s decision to pursue hospice care. Nonetheless, survival of 37 months in a case of MGMT-unmethylated glioblastoma is significantly above the expected median survival for this patient population. Further research is needed to better understand the role of GT brachytherapy in recurrent high-grade glioma and whether repeat implantation is a safe and viable treatment option. Section title: Conclusions Educational score: 4.05087947845459 Domain: biomedical Document type: Clinical case Language: en Despite advances in chemotherapy, EBRT, and tumor-treating fields over the past two decades, outcomes for patients with glioblastoma remain poor, and there is currently no established standard of care for recurrent disease. Repeat resection and GT brachytherapy offer a potential treatment option for patients with recurrent high-grade glioma, and studies are ongoing to evaluate its use in newly diagnosed glioblastoma. This report highlights a case in which a patient diagnosed with glioblastoma underwent two separate GT implantations during their treatment course and survived for 37 months without evident treatment-related toxicity. | Review | biomedical | en | 0.999997 |
PMC11698533 | Section title: Introduction and background Educational score: 4.048039436340332 Domain: biomedical Document type: Review Language: en Until recently, it was common practice to categorize musculoskeletal disorders as a single entity . As our knowledge of the human body has improved, etiopathogenetic differences between disorders affecting various components of the musculoskeletal structure have emerged . Researchers used to focus on the physiology and pathology of certain muscle components and the therapeutic interventions targeting them . However, research results from the past 20-30 years suggest it is a mistake to treat contractile muscle tissue as a standalone entity separate from connective tissue, even if the relationship is not yet clear . Recent findings indicate that what has traditionally been identified as muscle is, in fact, largely composed of connective tissue, which we now refer to as fascia, and which plays a fundamental role . Section title: Review Educational score: 1.2622963190078735 Domain: biomedical Document type: Other Language: en An introduction to fascia Section title: Review Educational score: 3.736323356628418 Domain: biomedical Document type: Review Language: en As stated in a recent article , an examination of the literature available on PubMed shows that the earliest mention of fascia in the medical and clinical field dates back to 1814 , while the term "fasciæ" appears in a journal from 1824 . According to the American Heritage Stedman’s Medical Dictionary , fascia is defined as "a sheet or band of fibrous connective tissue enveloping, separating, or binding together muscles, organs, and other soft structures of the body." Therefore, only well-defined fibrous connective tissue layers should properly be referred to as fascia, and it is inaccurate to use this term to describe all connective tissues in the body. Section title: Review Educational score: 4.346280574798584 Domain: biomedical Document type: Study Language: en Fascia is a viscoelastic tissue that forms an uninterrupted, three-dimensional collagen matrix . This tissue permeates the entire body, surrounding, supporting, protecting, connecting, and dividing the multiple muscular and visceral components of the organism . Fascia performs several physiological and functional roles related to joint stability, general movement coordination, proprioception, and nociception . Most importantly, it is responsible for transmitting mechanical forces (mechanotransduction) . Due to its presence in every tissue at multiple hierarchical levels, fascia represents the main structural interconnective element, both externally and internally, between the different constituents of the human body. Huijing et al. found that only 70% of muscle tension is transferred through tendons, which confirms their mechanical role. However, the remaining 30% of muscle force is conveyed to the connective tissue surrounding muscles, underscoring the deep fasciae's function in coordinating agonist, antagonist, and synergistic muscles at the peripheral level. Section title: Review Educational score: 1.982890009880066 Domain: biomedical Document type: Other Language: en Fascia and fascia system classification Section title: Review Educational score: 4.276074409484863 Domain: biomedical Document type: Review Language: en In the literature, various classifications of fascia exist . For example, in an attempt to organize the nomenclature for fascial structures provided by the Federative International Committee on Anatomical Terminology (FICAT) , a functional classification system was developed that includes four categories of fascia: connecting, fascicular, compressive, and separating fascia. Each category was developed from descriptions in the literature on macroscopic anatomy, histology, and biomechanics; the category names reflect the function of the fascia. More recently, the Foundation of Osteopathic Research and Clinical Endorsement (FORCE), an organization that brings together various scientific figures from a multidisciplinary perspective, tried to find a common nomenclature that can be shared, starting from the scientific notions currently available . Additionally, the Fascia Nomenclature Committee has proposed the following definition for the term fascia: "A fascia is a sheath, a sheet, or any other dissectible aggregations of connective tissue that forms beneath the skin to attach, enclose, and separate muscles and other internal organs” . Instead, the final definition of the Fascial System proposed by a subcommittee of five members from the Fascia Nomenclature Committee is: "The fascial system consists of the three-dimensional continuum of soft, collagen-containing, loose and dense fibrous connective tissues that permeate the body. It incorporates elements such as adipose tissue, adventitiae and neurovascular sheaths, aponeuroses, deep and superficial fasciae, epineurium, joint capsules, ligaments, membranes, meninges, myofascial expansions, periostea, retinacula, septa, tendons, visceral fasciae, and all the intramuscular and intermuscular connective tissues including endo-/peri-/epimysium” . Section title: Review Educational score: 4.004561901092529 Domain: biomedical Document type: Study Language: en For the purpose of this work, we will consider the simplified subdivision by Stecco et al. , an Italian researcher who has significantly contributed to the study of fascial systems. He classifies the simple fascial component involved in mechanotransduction into three main areas: (a) Superficial: This fascial layer is closest to the body’s surface and includes tissues such as the superficial fascia of the body and the subcutaneous fascia. (b) Deep: This fascial layer is located deeper than the first layer and includes structures such as the deep muscle fascia and the epimysial fascia that envelop the muscles. (c) Visceral: This is the innermost of the three fascial layers and surrounds the internal organs, providing structural support and facilitating organ movements within the body. The deep fascia is a continuous layer running from the trunk through to the upper and lower limbs and is considered the key element for transmitting loads in parallel, bypassing the joints . Section title: Review Educational score: 3.017616033554077 Domain: biomedical Document type: Study Language: en The focus of this work will primarily be on the fascia involved in the transmission of tension essential for body movement, such as that produced by muscles, as it provides the insertion and/or origin for all muscle fibers, with an estimated percentage of approximately 30% . Section title: Review Educational score: 1.560522198677063 Domain: biomedical Document type: Other Language: en Composition of fascia Section title: Review Educational score: 4.284965991973877 Domain: biomedical Document type: Study Language: en Fascia is an uninterrupted structure composed of layers of dense connective tissue (type I and III collagen) interfaced with loose connective tissue. It exhibits the typical properties of viscoelastic structures . In addition to fibers and cells, connective tissue systems also comprise an extracellular matrix (ECM) . This ECM surrounds cells, protects them, holds them together, and also provides physical and biochemical signals that play a key regulatory role in determining the shape and activities of a cell. It can take various forms in different tissues but is generally composed of similar fibrous (non-globular) macromolecules secreted into the extracellular space, where they self-assemble. The macromolecules that make up the ECM are mainly glycoproteins; in animals, collagen is by far the most abundant protein. In addition to collagen, the matrix also contains proteoglycans, fibronectin, and laminin. According to Bordoni et al. , it is important to include the liquid component (liquid fascia) as part of the fascia's composition. Section title: Review Educational score: 1.9818750619888306 Domain: biomedical Document type: Other Language: it Myofascial pain Section title: Review Educational score: 4.209526062011719 Domain: biomedical Document type: Review Language: en The "motor unit" or "muscle" has traditionally been seen as the fundamental unit in movement control. However, recent research has highlighted the significant interaction between muscle fibers and intramuscular connective tissue, as well as between muscles and fasciae, indicating that muscles alone cannot be regarded as the sole organizers of movement. Additionally, muscle innervation and blood supply are closely linked with intramuscular connective tissue . This realization led Luigi Stecco, in 2002 , to coin the term "myofascial unit" to emphasize the interconnected relationship, both anatomically and functionally, between fascia, muscles, and their associated structures. Section title: Review Educational score: 4.283785820007324 Domain: biomedical Document type: Review Language: en The stiffening of connective tissue is a feature of various painful syndromes . Indeed, localized increases in fascial rigidity are observed in certain "muscular" contractures - an abnormal increase in the passive stiffness of muscles - which are marked by dense connective tissue abundant in myofibroblasts and often linked to ongoing inflammatory processes . Some studies have clarified the mechanisms by which stretching, applied to conditions of myofascial stiffening, can improve the range of motion (ROM) and reduce pain, as reported by a review study . The painful syndromes most frequently associated with the stiffening of localized connective tissue include compartment syndrome of the lower leg induced by exercise, runner's knee (iliotibial friction band), tennis/golfer's elbow, frozen shoulder, plantar fasciitis, and Dupuytren's disease . Other examples of conditions caused by localized stiffness that can manifest even without pain include scoliosis and high-arched feet. General conditions of increased stiffness include spastic paralysis such as after a stroke, neuromuscular diseases such as Parkinson's disease, and autoimmune diseases such as rheumatoid arthritis or scleroderma. Section title: Review Educational score: 4.228750705718994 Domain: biomedical Document type: Study Language: en In these pathological conditions, histological studies reveal accumulations of fibroblasts or contractile myofibroblasts . Although hypotheses have been proposed, it is still not entirely clear if and how these cells contribute to the development of connective tissue-induced contractures . Recent findings also indicate that the fascial epimysium is pivotal in the pathogenesis of delayed onset muscle soreness (DOMS), which occurs following intense physical activity without adequate preparation . In addition, increased ECM density may contribute to myofascial pain . Painful contractures are especially associated with an increase in fascial tissue thickness, resulting in increased relative stiffness . Section title: Review Educational score: 4.410494804382324 Domain: biomedical Document type: Study Language: en It has also been suggested that nonspecific back pain may be mediated, at least in part, by fascial structures ; the thoracolumbar fascia, in particular, absorbs a significant portion of the mechanical force transmitted during lumbar flexion and is rich in nociceptive nerve endings . Tears, microlesions, and mechanical irritations of the thoracolumbar fascia can cause malfunctions and painful contractures. The same applies to the musculo-connective structures of the hip, where a significant number of nerve endings have been found not only in the skin (64.0 ± 5.2/cm 2 ), where they are most concentrated, but also in the subdermal tissue (24.0 ± 1.4/cm 2 ), superficial fascia (33.0 ± 2.5/cm 2 ), and deep fascia (19.0 ± 5.0/cm 2 ) . It is interesting to note that in men with chronic back pain, there is a tendency toward increased thickness of the thoracolumbar fascia compared with healthy subjects . Furthermore, a reduction in shearing movement, or the ability to glide during passive lumbar flexion, has been documented in this fascial structure in relation to the underlying musculature in both sexes . According to Stecco et al. , one of the issues with fascial system gliding, which causes densification and pain, is partly due to an alteration in the production of hyaluronic acid, an important lubricant located between fascial layers. Section title: Review Educational score: 2.1421947479248047 Domain: biomedical Document type: Other Language: en Myofascial pain syndrome Section title: Review Educational score: 4.438845157623291 Domain: biomedical Document type: Review Language: en Although experts in the field have not reached a consensus on the etiology and pathogenesis of myofascial pain syndrome , primarily due to the lack of specific laboratory markers and imaging evidence that would enable a unified diagnostic criterion, in general, the term myofascial pain syndrome describes sensory, motor, and autonomic symptoms attributed to myofascial trigger points (MTrPs) . MTrPs, which consist of numerous contraction knots, are defined as highly sensitive areas within taut, discrete bands of hardened muscle, leading to localized and referred pain along with other symptoms. Each contraction knot appears as a section of muscle fiber characterized by markedly contracted sarcomeres and an increased fiber diameter. The integrated MTrP hypothesis suggests that, in cases of myofascial pain, motor endplates release excessive acetylcholine, histopathologically indicated by shortened sarcomeres . These zones of intense focal sarcomere contraction have been documented in both animals and humans. Although MTrPs are thought to be quite prevalent, there is limited quality literature available on their exact prevalence . Section title: Review Educational score: 4.003716468811035 Domain: biomedical Document type: Other Language: en MTrPs can be divided into active or latent types. An active MTrP causes a clinical pain disturbance. It is always tender and produces recognizable pain upon compression. It inhibits the full extension of the muscle, weakens the muscle, and mediates a local contraction response of muscle fibers when adequately stimulated . A latent MTrP is clinically asymptomatic and only painful when palpated with some force. A latent MTrP may have all the other physical characteristics of an active MTrP and always presents within a tight band that increases muscle tension and limits the ROM . Section title: Review Educational score: 4.462187767028809 Domain: biomedical Document type: Study Language: en The underlying mechanisms of MTrPs have only recently started to be elucidated. Jarvholm et al. report that elevated intramuscular pressure in the supraspinatus substantially restricts local muscle blood flow, likely resulting in hypoperfusion and ischemia in the area. The partial oxygen pressure (pO 2 ) within regions of muscle hardening, termed myogeloses - presumed clusters of multiple MTrPs - has been found to be extremely low (near zero) at the center of an MTrP region . This notably low pO 2 is likely associated with a deficiency in adenosine triphosphate (ATP), a factor that may contribute to the localized hypercontractions (contractures) observed in these areas. ATP is essential for breaking myofilament bonds and stopping muscle contraction. Current data on myofascial pain indicate that the discomfort linked to active MTrPs may be indirectly related to reduced blood supply in the affected region. Hypoperfusion, for instance, can lead to low pO 2 and contractures. Additionally, it is known that low pO 2 significantly promotes the release of bradykinin, which sensitizes muscle nociceptors. Section title: Review Educational score: 4.275347709655762 Domain: biomedical Document type: Study Language: en Since capillary pressure ranges from around 35 mmHg at the beginning (arterial side) to approximately 15 mmHg at the end of the capillary network (venous side), capillary blood flow is transiently obstructed during muscle contractions . Blood flow immediately restores with relaxation, consistent with its normal physiological mechanism. In dynamic rhythmic contractions, intramuscular blood flow is improved by this contraction-relaxation rhythm, also known as the muscle pump. However, during sustained muscle contractions, muscle metabolism is highly dependent on oxygen and glucose levels, which are reduced due to altered vascular dynamics. Contractions performed at 10% to 25% of maximal voluntary contraction are sufficient to produce high intramuscular pressures that significantly compromise intramuscular blood flow . Section title: Review Educational score: 3.96894907951355 Domain: biomedical Document type: Study Language: en According to Bron and Dommerholt , these increases in pressure gradient, even during low-level efforts, producing hypoxia, can contribute to the formation of MTrPs and ultimately to the development of pain symptoms . Often referred to in the literature as myofascial pain syndrome , its symptomatology involves the muscular, sensory, motor, and autonomic nervous systems, caused by the stimulation of MTrPs . Section title: Review Educational score: 2.271136522293091 Domain: biomedical Document type: Other Language: en Fascia and the simplified model of force transmission Section title: Review Educational score: 4.073725700378418 Domain: biomedical Document type: Study Language: en In the functional classification of the fascial system , as previously outlined, one of the main roles is the transmission of forces. To understand how the fascial system performs the task of force transmission, in terms of both stability and movement, we must refer to Hill's model. One of the most common and simplified versions of the muscle model proposed by Hill consists of three elements: a contractile (active) element in series with an elastic (passive) element and both in parallel with another elastic (passive) element . It is the contractile element that is responsible for the change in muscle length and the generation of force when the muscle is activated. Section title: Review Educational score: 4.189906597137451 Domain: biomedical Document type: Study Language: en Although this simplified interpretation is not unanimously accepted, as it is considered one-dimensional , it remains a useful model to explore this topic in greater depth in this article. Its basic structure is schematically composed of (a) contractile component, typically identified with the sliding filaments of actin and myosin, where the force generated depends on the number of active cross-bridges between these filaments; (b) connective component, often linked to the intrinsic elasticity of the myofilaments and cross-bridges, as well as the tendons; and (c) parallel component, associated with the elasticity of connective tissues such as the epimysium, perimysium, and endomysium, along with the sarcolemma . Section title: Review Educational score: 3.8105056285858154 Domain: biomedical Document type: Study Language: en According to Huijing , the real situation becomes further complicated because these individual units in turn combine in series and in parallel. While the role of the in-series connective systems is to transfer, usually to the bone, the tension developed by the shortening of the muscle contractile component, the parallel component is responsible for energy recycling. Indeed, many movements in animals, including humans, are cyclic in nature and are associated with a stretch-shortening cycle of the myofascial complex . Section title: Review Educational score: 4.105733871459961 Domain: biomedical Document type: Study Language: en Many myofascial systems are built to take mechanical and energetic advantage of the stretch-shortening cycle through their parallel elastic elements, influencing the rate of change of the muscle’s contractile elements , storing and releasing potential energy , and increasing work output during the shortening phase through mechanisms of residual force enhancement . The effectiveness of energy storage in fascial tissue is further exemplified by animals such as gazelles and kangaroos, which use the fascial tissue in their lower limbs as an elastic spring . Another example can be observed in athletes with below-knee amputations, who, using a passive system made of elastic metal blades that essentially replace the parallel myofascial component, are able to reach high speeds during running . Section title: Review Educational score: 2.2045738697052 Domain: biomedical Document type: Other Language: en Myofascial pain syndrome - new etiopathogenetic hypothesis Section title: Review Educational score: 4.3832478523254395 Domain: biomedical Document type: Study Language: en The hypothesis we propose is that myofascial pain syndrome, caused by the formation of MTrPs, may be linked to an altered load of connective systems, as schematized by Hill's model . In the case of incorrect use of parallel connective systems, which are crucial for joint stability, the serial fascial system may be compensating through muscle activation. This activation is constant, not for dynamic purposes (i.e., for producing movement), but for static purposes related to stabilization. Muscle activation within a non-extensible connective sheath may increase internal pressure, reducing blood flow as proposed by Jarvholm et al. in the supraspinatus muscle. This mechanism seems plausible in cases of lower back pain (LBP) where the absence of the flexion relaxation phenomenon (FRP) represents the compensation of serial connective systems, with associated muscle activation observed electromyographically during trunk flexion postures. Section title: Review Educational score: 4.170282363891602 Domain: biomedical Document type: Study Language: en FRP, as studied by Floyd and Silver in maximum trunk flexion during upright standing, has also been observed in subjects during slumped sitting postures . These postures are commonly adopted during daily life, especially given the time many people spend sitting in chairs, sofas, and armchairs. Such compensatory muscle contraction may trigger a vascular crisis, which may in turn lead to the formation of MTrPs, as identified via ultrasound in the thoracolumbar fascia and erector spinae muscles . The results of a study focusing on ultrasound measurements of the thickness of the thoracolumbar fascia and multifidus muscle indicate that individuals with chronic LBP exhibit thickening of the thoracolumbar fascia and thinning of the lumbar multifidus muscle compared with healthy control groups. In particular, an increase in thoracolumbar fascia thickness was correlated with pain intensity, while a reduction in multifidus muscle thickness was associated with decreased lumbar flexion capacity. The authors emphasized the importance of incorporating tailored rehabilitation regimens for LBP patients that target both fascial and muscular components. Another study confirms the reduction in multifidus thickness in patients with LBP. Section title: Review Educational score: 1.7033437490463257 Domain: biomedical Document type: Other Language: en Fascial treatment - stretching Section title: Review Educational score: 3.9673023223876953 Domain: biomedical Document type: Study Language: en Many studies suggest treatments aimed at stretching the fascia , including manual techniques and stretching exercises . The goal of these therapies is to modify the mechanical properties of the fascia, such as density, stiffness, and viscosity so that it can more easily adapt to physical stress . In fact, manual therapists report a localized release of tissues following the application of slow manual force to abnormally tense fascial areas . These outcomes have been explained as a disruption of fascial cross-links, a transition from a gel state to a sol state in the ECM, as well as other passive viscoelastic changes in the fascia . Section title: Review Educational score: 1.976141333580017 Domain: biomedical Document type: Other Language: en Therapeutic fascial stretching Section title: Review Educational score: 4.095462799072266 Domain: biomedical Document type: Review Language: en In the early 1900s, Sherrington defined the underlying concepts of neuromuscular facilitation and inhibition. These later led to the development of clinical stretching techniques described by Kabat as proprioceptive neuromuscular facilitation (PNF). PNF is based on neurophysiological phenomena, particularly reciprocal inhibition: the process wherein, when a muscle group is activated, its antagonist is inhibited. Initially, PNF techniques were used for the rehabilitative treatment of patients with spasticity and paresis, facilitating muscle stretching. Soon after, the therapeutic use of PNF was extended to patients with conditions of non-neurological origin , including more common complaints treated in sports medicine . Section title: Review Educational score: 3.9049532413482666 Domain: biomedical Document type: Other Language: en Two commonly used PNF-stretching techniques are contract-relax (CR) and contract-relax followed by agonist contraction (CRAC). During the CR technique, the therapist passively brings the target muscle group of the patient - the group to be stretched - to the point of maximal resistance, referred to as the barrier , where further stretching or ROM is limited. In this position, the treated muscles are contracted isometrically for a few seconds and then stretched to a new barrier. Section title: Review Educational score: 4.107290267944336 Domain: biomedical Document type: Study Language: en Some authors further differentiate between CR techniques and the hold-relax (HR) method, depending on the type of contraction used before stretching . Theoretically, CR involves an isotonic contraction resisted by the therapist, while HR requires a resisted isometric contraction . Both methods, rooted in the PNF approach, are applied with the intention of stimulating sensory receptors that provide information about body position and movement to facilitate the desired movement . In both cases, the joint or body part is actively or passively repositioned to the new limit of the ROM following contraction . The primary mechanism underlying this technique is postulated to be the inverse myotatic reflex, also known as autogenic inhibition, due to the action of Golgi tendon organs (GTOs) . In autogenic inhibition, maximal muscle contraction activates the GTOs - structures sensitive to force - thereby inhibiting the alpha motor neurons of the same muscle via type-Ib inhibitory interneurons. Section title: Review Educational score: 4.167840957641602 Domain: biomedical Document type: Review Language: en A 2006 review reports that these techniques often vary in their descriptions and are referred to by different names. For example, the CRAC technique consists of two phases: the first is identical to the CR technique, while the second phase adds a contraction of the antagonist muscle group as the therapist stretches the target muscle group. The CRAC technique appears to exploit the myotatic reflex, meaning that the increased discharge frequency of the spindles in the antagonist muscle (due to isometric contraction) stimulates Ia inhibitory interneurons, which in turn inhibit the alpha motor neurons of the antagonist muscles . This should lead to a relaxation of the activated muscles and/or a reduction in the amplitude of the muscle stretch reflex response . Kabat attributed this to the induction resulting from the second phase and used it to develop a PNF strengthening technique, which became known as "antagonist reversal" . Several studies have reported that PNF stretching techniques led to greater increases in ROM compared with static or ballistic stretching. This response seems to be due to the relaxation of the muscle being stretched, as a result of reflex inhibition . Section title: Review Educational score: 4.087394714355469 Domain: biomedical Document type: Study Language: en The hypothesis that PNF exerts its effects through muscle activity inhibition has been challenged by several researchers. Using surface electromyography (EMG), Moore and Hutton studied the relative level of relaxation of the hamstring muscles achieved during different types of stretching. They found that the CRAC technique not only produced the greatest increase in ROM but also significantly higher EMG activity compared with the static or CR technique. Subsequent surface EMG studies evaluating various stretching techniques confirmed, as defined by Etnyre and Abraham , the apparent paradox that, when using PNF stretching techniques, the greatest ROM gains coincide with increased EMG activation of the stretched muscle, rather than a reduction. Section title: Review Educational score: 4.361898422241211 Domain: biomedical Document type: Study Language: en Furthermore, several years ago, Chalmers questioned the neurophysiological foundations of CR, particularly the role of GTOs. After this article appeared, several other authors also expressed doubts about the actual mechanisms underlying PNF techniques and stretching methods in general. Traditionally, it has been considered that GTOs serve as "safety devices" that help prevent excessive force during muscle contraction . When the forces of muscle contraction and external factors combine to a point where injury to the muscle, tendon, or bone becomes possible, GTOs generate inhibitory postsynaptic potentials on the cell bodies of the agonist motor units . According to Moore , recent research has demonstrated that these concepts regarding GTO physiology are inaccurate. The new evidence can be summarized as follows: (a) GTOs respond throughout the entire ROM, even to weak active and passive contractions, although they are much less sensitive to passive contractions than active ones. (b) GTO impulses likely reach the cerebral cortex, informing the spatial position of the limbs. (c) GTOs and their autogenic inhibition reflex reduce, but do not deactivate, the excitability of the motor neurons and the innervated muscle. (d) During CR stretching, the GTO autogenic reflex induces a momentary inhibition that persists only for the duration of the active muscle contraction. Therefore, it is unlikely that GTO activity significantly influences the subsequent relaxation phase, as proposed in earlier literature . Section title: Review Educational score: 4.145544528961182 Domain: biomedical Document type: Study Language: en The cause of the hypothesized change in stretch perception with PNF stretching remains unknown. Increased stretch tolerance has been proposed to explain the acute increases in ROM observed with static stretching and as the basis for the greater ROM in individuals with greater relative physiological flexibility, particularly in the hamstring muscles . However, if we simply attribute the increased ROM induced by stretching to greater pain tolerance during the stretch, this cannot explain how, in addition to increased joint mobility, there is also a reduction in "muscular stiffness" immediately after exercise, as assessed by ultrasound shear-wave . Other studies using the same method have confirmed the acute reduction in muscle stiffness at rest following stretching . Section title: Review Educational score: 1.4895774126052856 Domain: biomedical Document type: Other Language: en Considering all this data, the question put forward by Carla Stecco in her article becomes more plausible: "Fascial or muscle stretching?" Section title: Review Educational score: 1.900591254234314 Domain: biomedical Document type: Other Language: en Neural aspect of stretching Section title: Review Educational score: 3.9950642585754395 Domain: biomedical Document type: Study Language: en The global relationship between the nervous system and the fascial system is highly complex. Starting with the simple constitution of what is referred to as nervous tissue, it actually involves a significant participation of supporting fascial tissue (endoneurium, perineurium, and epineurium). Further complicating the picture is the response of these fascial structures to mechanical stress in relation to the activity of the autonomic nervous system (sympathetic and parasympathetic systems), which certainly plays a role in the determination of baseline tension states. Based on the current information available, there is insufficient data to fully define these relationships. For this reason, we will limit our discussion to the hypothesized afferent responses of fascial system receptors, specifically regarding force transmission. Section title: Review Educational score: 4.098744869232178 Domain: biomedical Document type: Study Language: en According to Schleip , the immediate fascial plasticity observed after manual treatment cannot be explained solely by the mechanical properties of the connective tissue system. The fascia is densely innervated by mechanoreceptors, which include Ruffini endings and a rich network of interstitial receptors with a high reactivity to tangential pressure. The manual stimulation of these sensory endings by the therapist’s manipulation likely leads to changes in the tone of motor units mechanically linked to the tissue involved. Therefore, it is not just mechanical action that is seen but also profound changes in the autonomic nervous system triggered by the stimulation of these receptors. Section title: Review Educational score: 3.927762508392334 Domain: biomedical Document type: Study Language: en Supporting Schleip's proposal is the work of Guissard and Duchateau , whose title “Neural aspects of muscle stretching” clearly reflects the authors’ stance. The idea that stretching interacts not only with the muscle component but also with the nervous component is not a recent discovery. To our knowledge, the earliest data date back to the work of Robinson et al. in 1982 , when the authors used the Hoffman neurological reflex evaluated with EMG to investigate the effect of stretching, which was erroneously termed muscular, referring to muscle as the tension-producing system. Section title: Review Educational score: 4.1025285720825195 Domain: biomedical Document type: Study Language: en Unlike rapid muscle stretching, static stretching does not enhance reflex activity in the stretched muscle but instead reduces spinal reflex excitability. This inhibitory effect can be evaluated in the soleus muscle by measuring the Hoffmann reflex (H-reflex) and the tendon reflex (T-reflex) through EMG. The H-reflex is triggered by electrically stimulating the Ia fibers of the tibial nerve in the popliteal fossa , whereas the T-reflex is elicited by tapping the Achilles tendon with a reflex hammer. Section title: Review Educational score: 2.463953733444214 Domain: biomedical Document type: Other Language: en Myofascial stretching and Hill's model Section title: Review Educational score: 2.4924352169036865 Domain: biomedical Document type: Study Language: en According to Shleip and Müller , different stretching styles seem to target the various components of fascial tissue, as described in Hill's model. Figure 2 illustrates some of these different target tissues affected by various loading regimes. Section title: Review Educational score: 4.070668697357178 Domain: biomedical Document type: Study Language: en Traditional weight training loads the muscle within its typical ROM, thereby reinforcing the fascial tissues aligned in series with the active muscle fibers. Additionally, the transverse fibers within the muscle sheath are also stretched and activated. However, minimal effects can be expected on extramuscular fascia and on those intramuscular fascial fibers arranged parallel to the active muscle components, as proposed by Huijing . On the other hand, classical stretching, in which the muscular contractile component is inactive, will show minimal effects on those fascial tissues arranged in series with the active muscle component. The reason is that relaxed myofibers, being much more elastic than their fascial/tendinous extensions arranged in series, can absorb most of the stretch . However, slow, light, and constant stretching provides good stimulation for tissues like the extramuscular fascia and the intramuscular fascia arranged parallel to the myofibers. Section title: Review Educational score: 2.397047758102417 Domain: biomedical Document type: Other Language: en In light of this presentation, a question arises: Is it possible that different stretching methods act on different components of fascial connective tissue? Section title: Review Educational score: 4.054098606109619 Domain: biomedical Document type: Study Language: en The classic method proposed in the 1980s by Anderson involves passively stretching the myofascial structures by separating the insertion points . In this situation, the first barrier to stretching is the parallel fascial component. Indeed, the muscular contractile component, due to the greater elasticity of the relaxed myofibrils, reduces the tension induced by the stretch on the series fascial component. Therefore, this method might stimulate the elongation only of the fascia arranged in parallel. Section title: Review Educational score: 4.11987829208374 Domain: biomedical Document type: Study Language: en The CR stretch, by activating the contractile component of the muscular system while in the stretched position produced by the previous method, may tend to primarily load tension onto the series fascial component in the Hill model, while simultaneously reducing the tension on the parallel system . On the other hand, the CRAC technique, especially in the second phase , which involves the contraction of the antagonist anterior muscles, further separates the insertion points of the posterior fascial system, involving the parallel fascial component. Section title: Review Educational score: 3.878558397293091 Domain: biomedical Document type: Other Language: en This model is novel because, instead of relying on the neurophysiological principles outlined by Sherrington (particularly considering the reconsideration of the function of the Golgi tendon organ previously discussed), it is primarily based on the effect of mechanical load on fascial components arranged in series and parallel. This model should also be considered when applying certain manual therapy techniques, such as muscle energy technique (MET) , which are directed toward the fascial system. Section title: Conclusions Educational score: 4.155831336975098 Domain: biomedical Document type: Study Language: en This article is the first, to our knowledge, to address fascia dysfunction in two modalities: excessive stiffness and reduced stiffness. This first part of an investigation of physical exercise and the fascial system provides an introduction to the composition of fascia and an overview of the methods proposed in the literature to address dysfunctions caused by excessive fascial rigidity. In addition, the neurophysiological principles underlying traditional muscle stretching are questioned, exploring a model that shifts the focus more toward the fascial component rather than the muscle's contractile component. By revisiting models that schematize the fascial system, such as Hill's finite element model, it attempts to apply these to the techniques most commonly proposed in the literature. This article presents a new hypothesis on how MTrPs may develop as a result of imbalanced tension loading on the fascial components arranged in series and parallel to the contractile muscular component. If future research were to confirm these hypotheses, it would follow that, for an effective and complete treatment of fascial system stretching, all three methods should be used in sequence. This model should also be considered when applying certain manual therapy techniques. | Review | biomedical | en | 0.999997 |
PMC11698535 | Section title: Introduction and background Educational score: 3.6195483207702637 Domain: biomedical Document type: Other Language: en Precision medicine, an approach that considers individual variability in genes, environment, and lifestyle to allow for more precise prediction and treatment, has significantly influenced various medical specialties . Integrating genomic data and advanced diagnostics has led to personalized therapies, particularly in fields such as oncology and cardiology . However, applying precision medicine principles in emergency medicine (EM) remains relatively underexplored. Section title: Introduction and background Educational score: 3.6376867294311523 Domain: biomedical Document type: Other Language: en EM is characterized by the need for rapid assessment and immediate decision-making to manage acute illnesses and injuries. Traditional EM practices often rely on generalized protocols designed for the average patient, which may not account for individual variations that can impact clinical outcomes . The heterogeneous nature of emergency department (ED) presentations underscores the potential benefits of adopting precision medicine approaches to tailor interventions more effectively. Section title: Introduction and background Educational score: 3.9537980556488037 Domain: biomedical Document type: Other Language: en Incorporating precision medicine into emergency care, termed precision emergency medicine (PEM), holds promise for enhancing diagnostic accuracy and optimizing therapeutic strategies. By leveraging patient-specific data such as genetic profiles, biomarkers, and point-of-care diagnostics, PEM could transform emergency care from a protocol-driven practice to one that is more personalized and outcome-focused . For example, pharmacogenomics could guide medication selection and dosing in the ED, reducing adverse drug reactions and improving efficacy. Section title: Introduction and background Educational score: 3.847815752029419 Domain: biomedical Document type: Review Language: en Several studies have begun to explore the integration of precision medicine in emergency settings, highlighting both opportunities and challenges. Kingsmore et al. demonstrated the potential of rapid whole-genome sequencing in critically ill infants, enabling timely and precise diagnoses that can significantly alter clinical management . Additionally, point-of-care ultrasound (POCUS) has been identified as a tool for delivering precision care in pediatric emergencies, allowing for individualized assessment and intervention . Section title: Introduction and background Educational score: 3.838728666305542 Domain: biomedical Document type: Review Language: en Despite these advancements, the literature on PEM is limited, with only a handful of studies directly addressing the topic. A recent search identified only a limited number of papers specifically focused on PEM, indicating a significant gap in research . This paucity of data underscores the need for comprehensive evaluations of how precision medicine principles can be effectively implemented in emergency care to improve patient outcomes. Moreover, challenges such as limited time for data analysis in acute settings, the need for rapid diagnostic tools, and ethical considerations related to genetic testing remain significant barriers to widespread adoption . Section title: Introduction and background Educational score: 4.051963806152344 Domain: biomedical Document type: Review Language: en This systematic review aims to critically evaluate the existing literature on PEM, focusing on the limited number of studies available. Specifically, it will analyze how precision medicine principles have been applied in emergency care settings, assess preliminary impacts on clinical outcomes, and identify reported barriers and facilitators to implementation. By synthesizing findings from these studies, the review seeks to provide a foundational understanding of PEM, highlight gaps in current knowledge, and propose directions for future research to advance the field. Section title: Review Educational score: 1.3877626657485962 Domain: biomedical Document type: Other Language: cy Methods Section title: Review Educational score: 1.3672782182693481 Domain: biomedical Document type: Other Language: da Study Design Section title: Review Educational score: 3.9882280826568604 Domain: biomedical Document type: Review Language: en This systematic review was conducted to evaluate the application of precision medicine principles in emergency care settings. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to ensure a transparent and replicable methodology . Section title: Review Educational score: 1.073331356048584 Domain: other Document type: Other Language: en Search Strategy Section title: Review Educational score: 4.014564514160156 Domain: biomedical Document type: Study Language: en A comprehensive literature search was conducted across multiple electronic databases, including PubMed, Embase, Cochrane Library, Scopus, and Google Scholar, covering articles published from January 2010 to October 2024 to capture the latest advancements in PEM. The search, completed in October 2024, employed a strategy that combined keywords and Medical Subject Headings (MeSH) terms related to precision and emergency medicine. Example search terms included phrases such as "precision medicine", "personalized medicine", "individualized medicine", "genomic medicine", "machine learning", and "artificial intelligence", combined with terms specific to emergency settings such as "emergency medicine", "emergency department", "acute care", and "emergency services". Additionally, the reference lists of relevant articles were manually reviewed to identify further studies that met the inclusion criteria. Section title: Review Educational score: 2.023653268814087 Domain: biomedical Document type: Study Language: en Inclusion and Exclusion Criteria Section title: Review Educational score: 4.0327911376953125 Domain: biomedical Document type: Study Language: en The inclusion and exclusion criteria for this study were defined to ensure relevance and rigor. The inclusion criteria encompassed studies involving patients in emergency care settings where precision medicine principles, such as genomics, machine learning (ML), point-of-care diagnostics, biomarkers, or personalized therapeutic strategies, were applied. Eligible study types included original research articles, reviews, editorials, consensus statements, and meta-analyses, focusing on English-language publications from January 2010 to October 2024. The exclusion criteria ruled out studies not directly related to precision medicine in emergency care, including case reports, conference abstracts, letters to the editor, non-peer-reviewed articles, and research focused on non-emergency settings or specialties outside EM. Section title: Review Educational score: 1.4356588125228882 Domain: biomedical Document type: Study Language: en Study Selection Section title: Review Educational score: 3.8846471309661865 Domain: biomedical Document type: Study Language: en All identified articles were imported into EndNote (Clarivate, Philadelphia, Pennsylvania) reference management software, and duplicates were removed. Two independent reviewers screened the titles and abstracts of the retrieved articles for eligibility based on the inclusion and exclusion criteria. Discrepancies between reviewers were resolved through discussion or consultation with a third reviewer. Additionally, full-text articles were obtained for studies that met the initial screening criteria. The same two reviewers independently assessed the full-text articles for final inclusion. The study selection process is documented in Figure 1 . Section title: Review Educational score: 1.2585316896438599 Domain: biomedical Document type: Other Language: en Data Extraction and Management Section title: Review Educational score: 4.032407760620117 Domain: biomedical Document type: Study Language: en Data extraction and management were conducted using a standardized form to capture essential information from the included studies. The extracted data encompassed study characteristics, including author(s), year of publication, and study design; focus areas, detailing specific precision medicine applications in emergency care settings; and key findings, highlighting the application of precision medicine principles, impacts on clinical outcomes, and identified barriers and facilitators to implementation. Two reviewers independently performed the data extraction, with any discrepancies resolved through discussion or consultation with a third reviewer to ensure accuracy and consistency. Section title: Review Educational score: 1.128065586090088 Domain: biomedical Document type: Other Language: en Quality Assessment Section title: Review Educational score: 3.9557557106018066 Domain: biomedical Document type: Review Language: en The quality of the included studies was assessed through a general appraisal of their relevance, credibility, and contribution to the topic of PEM. Given the diversity of study designs, including original research articles, reviews, an editorial, and a consensus conference report, and the exploratory nature of this review, a formal quality appraisal using standardized tools was supplemented with a detailed bias assessment. Each study was evaluated based on its relevance to the research question, ensuring that it directly addressed the application of precision medicine principles in emergency care settings. Section title: Review Educational score: 4.000439167022705 Domain: biomedical Document type: Study Language: en To provide a transparent evaluation of study quality, we examined potential biases specific to each study type, categorizing risks as low, high, or unclear. Table 1 presents a summary of the risk of bias across the included studies, focusing on factors such as selection, performance, detection, reporting, confounding, and conflict of interest biases. Additionally, the clarity and transparency of objectives, methodologies, and findings were considered to determine the reliability of the information presented. Finally, the contribution of each study to the field was assessed by examining the significance of its findings in advancing the understanding of PEM. Section title: Review Educational score: 1.208998680114746 Domain: biomedical Document type: Other Language: en Data Synthesis Section title: Review Educational score: 3.3570501804351807 Domain: biomedical Document type: Study Language: en A qualitative synthesis of the findings was conducted due to the heterogeneity of the studies in terms of interventions and outcomes measured. The studies were grouped based on the focus area of precision medicine applications in emergency care, such as genomic applications, ML, point-of-care diagnostics, and education. Section title: Review Educational score: 1.065622329711914 Domain: biomedical Document type: Other Language: et Results Section title: Review Educational score: 3.9565205574035645 Domain: biomedical Document type: Review Language: en The initial database search yielded 218 records. After removing duplicates and screening titles and abstracts, 35 articles were selected for full-text review. Of these, 25 articles were excluded for not meeting the inclusion criteria, such as not focusing directly on PEM or lacking relevant data. Ultimately, 10 studies were included in the systematic review. The 10 included studies comprised original research articles (n = 5), reviews (n = 3), an editorial (n = 1), and a consensus conference report (n = 1). The studies were published between 2015 and 2024. The characteristics of the included studies are summarized in Table 2 . Section title: Review Educational score: 2.167273759841919 Domain: biomedical Document type: Other Language: en Application of Precision Medicine Principles in Emergency Care Section title: Review Educational score: 3.8772518634796143 Domain: biomedical Document type: Review Language: en Genomic and molecular applications: Several studies highlighted the use of genomic data in emergency settings. Limkakeng et al. described how systematic molecular phenotyping, including genomics, proteomics, and metabolomics, can transform emergency care by enabling precise diagnoses based on individual patient profiles . They emphasized that while this approach holds great promise, challenges such as cost, turnaround time, and the need for rapid interpretation of complex data in acute settings are significant barriers that need to be addressed. Section title: Review Educational score: 3.406024694442749 Domain: biomedical Document type: Review Language: en ML and data science: Lee et al. explored the role of ML and artificial intelligence (AI) in EM, discussing how these technologies enhance precision medicine by enabling predictive analytics and personalized care plans . They highlighted that ML is transforming diagnostic processes, especially in predicting conditions such as sepsis, thus improving real-time clinical decision-making, risk stratification, and personalized treatment. Section title: Review Educational score: 3.2241618633270264 Domain: biomedical Document type: Other Language: en Salhi et al. developed a framework for integrating big data and technology to improve healthcare delivery and access in EM . They identified core domains such as personalized ED care, expedited prehospital care, and prediction tools for system readiness, underscoring the importance of data science in advancing PEM. Section title: Review Educational score: 3.867473840713501 Domain: biomedical Document type: Review Language: en Point-of-care diagnostics and biomarkers: POCUS was identified as a valuable tool for delivering precision care. Kessler et al. reviewed cutting-edge applications of POCUS in pediatric emergency care, suggesting that it allows for personalized assessment and intervention . Shaban et al. conducted a systematic review and meta-analysis demonstrating that POCUS is highly effective in diagnosing abdominal aortic aneurysm (AAA) in the ED, supporting its role in PEM . Section title: Review Educational score: 3.8018910884857178 Domain: biomedical Document type: Review Language: en Both Kessler et al. and Sanz-García et al. emphasized the importance of using biomarkers and early warning scores (EWS) to create individualized diagnostic pathways in emergency settings . Biomarkers and EWS help identify patients at risk for clinical deterioration, adding specificity to diagnostics and optimizing treatment timing and choice, thereby improving outcomes. Section title: Review Educational score: 3.359013795852661 Domain: biomedical Document type: Other Language: en Biomarkers and EWS: Sanz-García et al. highlighted the need for incorporating biomarkers and EWS to enhance diagnostic accuracy and patient outcomes in acute settings . The use of these tools facilitates high-precision EM by enabling clinicians to identify subtle changes in a patient's condition that may indicate impending deterioration. Section title: Review Educational score: 3.6125800609588623 Domain: biomedical Document type: Other Language: en Health professions education: The integration of PEM into medical education was addressed by Chan et al. , who emphasized the existing gap in precision medicine education among emergency physicians . They proposed a research agenda for educating future emergency physicians, stressing the importance of comprehensive training programs that include structured education in genomic medicine, ML, and AI. By equipping clinicians with these skills, the EM workforce can be better prepared for future precision medicine applications. Section title: Review Educational score: 1.5754873752593994 Domain: biomedical Document type: Other Language: en Impact on Clinical Outcomes Section title: Review Educational score: 3.7888176441192627 Domain: biomedical Document type: Review Language: en While the studies suggest potential improvements in diagnostic accuracy and personalized care, direct evidence of improved clinical outcomes is still emerging. Kingsmore et al. reported that rapid genomic diagnostics could alter clinical management in critically ill infants, potentially improving outcomes by enabling timely, targeted interventions . Shaban et al. found that the use of POCUS in diagnosing AAA led to accurate detection and management, which could translate into reduced morbidity and mortality . Section title: Review Educational score: 1.6376445293426514 Domain: biomedical Document type: Other Language: en Barriers and Facilitators to Implementation Section title: Review Educational score: 4.058914661407471 Domain: biomedical Document type: Study Language: en Barriers: Common barriers identified across the studies include time constraints, technological limitations, education and training gaps, and ethical and privacy concerns. The acute nature of emergency care limits the time available for comprehensive data analysis , making it challenging to integrate complex genomic data into fast-paced emergency environments. Technological limitations are evident in the need for rapid and accurate diagnostic tools that can be feasibly implemented in the ED, as the cost and turnaround time for technologies like whole-genome sequencing can be prohibitive . Additionally, there is a noted lack of familiarity among emergency physicians with precision medicine tools and techniques , highlighting the need for comprehensive training programs. Ethical and privacy concerns related to genetic testing and data security further complicate the adoption of precision medicine, with issues such as informed consent, potential for genetic discrimination, and data security being significant . Section title: Review Educational score: 3.733327627182007 Domain: biomedical Document type: Other Language: en Facilitators: Facilitators for implementing PEM include advancements in technology, interdisciplinary collaboration, and education initiatives. The development of rapid sequencing technologies and portable diagnostic tools supports the practical application of precision medicine in EDs . Interdisciplinary collaboration among data scientists, clinicians, educators, and policymakers is essential for integrating precision tools into EM , as it helps address technological and logistical challenges. Furthermore, incorporating precision medicine into medical curricula prepares future physicians to utilize these tools effectively , with structured training in genomic medicine, ML, and AI being crucial for advancing PEM. Section title: Review Educational score: 3.6442954540252686 Domain: biomedical Document type: Review Language: en The existing literature on PEM is limited but growing. The studies reviewed provide insights into various aspects of precision medicine in emergency care, including genomic applications, ML, point-of-care diagnostics, biomarkers, and educational needs. While there is enthusiasm for the potential of PEM, significant barriers, such as time constraints, technological limitations, ethical concerns, and training gaps, must be addressed to realize its full impact on patient care. Section title: Review Educational score: 3.24526309967041 Domain: biomedical Document type: Other Language: en These findings illustrate the current applications and challenges of PEM. Advances in ML, genomic profiling, point-of-care tools, and education are driving the future of this field. Addressing ethical and logistical barriers is crucial for the full implementation of precision medicine in emergency settings, with the goal of enhancing patient outcomes in real-life clinical settings. Section title: Review Educational score: 1.083368182182312 Domain: other Document type: Other Language: de Discussion Section title: Review Educational score: 3.9836370944976807 Domain: biomedical Document type: Review Language: en This systematic review critically evaluated the existing literature on PEM, focusing on the application of precision medicine principles in emergency care settings, their impact on clinical outcomes, and the barriers and facilitators to implementation. The inclusion of additional in-depth analyses in our results has enriched our understanding of how precision medicine is currently being integrated into EM and the potential it holds for transforming patient care. Section title: Review Educational score: 3.9002604484558105 Domain: biomedical Document type: Study Language: en The findings demonstrate that precision medicine applications in emergency settings can significantly enhance diagnostic accuracy and personalize patient care. An illustrative example is provided by Kingsmore et al. , who utilized rapid whole-genome sequencing (STATseq) in critically ill infants, resulting in timely and precise diagnoses that significantly influenced clinical management and outcomes . This breakthrough underscores the practical feasibility and clinical impact of integrating genomic profiling into acute care settings. Section title: Review Educational score: 3.7419633865356445 Domain: biomedical Document type: Review Language: en Similarly, the use of POCUS has been shown to facilitate personalized assessment and intervention. Kessler et al. and Shaban et al. demonstrated the efficacy of POCUS in pediatric emergencies and AAA diagnosis, respectively, highlighting how point-of-care diagnostics can contribute to precision care by providing immediate, patient-specific information that guides clinical decisions . Section title: Review Educational score: 3.627626419067383 Domain: biomedical Document type: Review Language: en Another promising development is the incorporation of ML and AI into EM. Lee et al. discussed how ML algorithms are transforming diagnostic processes, particularly in predicting conditions such as sepsis, thereby improving real-time clinical decision-making and risk stratification . These technologies enable the analysis of large datasets to identify patterns and predict outcomes on an individual level, aligning with the goals of precision medicine. Section title: Review Educational score: 3.733356237411499 Domain: biomedical Document type: Other Language: en Despite these advancements, the integration of precision medicine into emergency care is not yet widespread. Several barriers contribute to this gap between potential and practice. Time constraints inherent in emergency care limit the feasibility of complex data analysis and interpretation required for genomic and molecular applications . Technological limitations, including the cost and turnaround time of advanced diagnostics such as whole-genome sequencing, further impede adoption . Section title: Review Educational score: 2.3145203590393066 Domain: biomedical Document type: Other Language: en Ethical considerations, particularly regarding genetic testing and data privacy, are significant concerns. The use of genomic data raises questions about informed consent, potential genetic discrimination, and the security of sensitive information . These issues necessitate the development of robust ethical guidelines and data protection measures. Section title: Review Educational score: 3.398071527481079 Domain: biomedical Document type: Other Language: en Insufficient education and training among emergency physicians is another critical barrier. Chan et al. emphasized the need for comprehensive training programs to equip clinicians with the necessary skills in genomic medicine, ML, and AI . Without adequate education, clinicians may be hesitant to adopt new technologies or may not utilize them effectively, limiting the potential benefits of precision medicine. Section title: Review Educational score: 3.818084955215454 Domain: biomedical Document type: Review Language: en When comparing our findings with previously published work, there is a consensus on both the potential benefits of PEM and the challenges that impede its adoption. Rizos et al. highlighted that while precision medicine has revolutionized fields like oncology, its application in EM is limited due to the acute nature of care and the need for rapid decision-making . This aligns with the barriers identified in our review and underscores the unique challenges of integrating precision medicine into EM. Section title: Review Educational score: 3.8704094886779785 Domain: biomedical Document type: Review Language: en The theoretical implications of these findings suggest that PEM could significantly enhance patient outcomes by tailoring interventions to individual needs. Practical applications are vast, ranging from the use of ML algorithms to predict patient deterioration to employing genomic data for precise pharmacotherapy in acute settings . As discussed by Sanz-García et al. , the use of biomarkers and EWS further illustrates how precision tools can aid in early detection and intervention, potentially reducing morbidity and mortality . Section title: Review Educational score: 4.130619049072266 Domain: biomedical Document type: Review Language: en Despite the promise, the path to implementing PEM is fraught with challenges. Addressing these barriers will require a multifaceted approach. First, investment in rapid, cost-effective diagnostic technologies suitable for emergency settings is essential, including the development of portable devices and point-of-care tools that provide immediate results to mitigate time constraints and enhance feasibility. Second, collaboration among clinicians, data scientists, educators, and policymakers is crucial, as such interdisciplinary partnerships can drive innovation, address technological limitations, and develop practical solutions tailored to the emergency care environment . Third, integrating precision medicine into medical curricula will prepare current and future emergency physicians to adopt these approaches effectively, with training programs focusing on genomic literacy, data interpretation, and ethical considerations . Fourth, establishing standardized protocols and ethical guidelines is imperative to address concerns related to data privacy, informed consent, and genetic discrimination, necessitating prioritization by policymakers and professional organizations . Lastly, advocacy for policies that support the integration of precision medicine into EM, including funding for research and infrastructure, can facilitate widespread adoption. By pursuing these strategies, the implementation of PEM can overcome existing barriers and realize its potential to transform emergency care. Section title: Review Educational score: 1.5644861459732056 Domain: biomedical Document type: Other Language: de Main Findings Section title: Review Educational score: 4.031054496765137 Domain: biomedical Document type: Review Language: en Our review highlights several key findings. First, the evidence base for PEM is limited but growing, with only 10 studies directly addressing the topic. This underscores a significant gap in research and emphasizes the need for more studies to build a robust evidence base. Second, the application of precision medicine principles in emergency settings shows promise for enhancing diagnostic accuracy and personalizing patient care, potentially leading to better clinical outcomes. Third, significant barriers to implementation have been identified, including time constraints, technological limitations, lack of education and training, and ethical concerns, all of which need to be addressed to facilitate the integration of PEM into clinical practice. Fourth, advancing PEM will require interdisciplinary collaboration and education, necessitating cooperation between clinicians, data scientists, educators, and policymakers, as well as the incorporation of precision medicine into medical education to prepare future emergency physicians. Lastly, the development of standardized protocols and guidelines is crucial for the safe and effective implementation of PEM. Section title: Review Educational score: 1.559439778327942 Domain: biomedical Document type: Other Language: it Limitations Section title: Review Educational score: 3.8506252765655518 Domain: biomedical Document type: Review Language: en This review has limitations. The small number of studies included reflects the limited research available on PEM, which may affect the generalizability of the findings. Additionally, the heterogeneity of the studies in terms of focus areas and methodologies makes it challenging to draw definitive conclusions. Publication bias may also be present, as studies with negative findings are less likely to be published. Section title: Review Educational score: 1.1585639715194702 Domain: other Document type: Other Language: fr Future Directions Section title: Review Educational score: 4.022106170654297 Domain: biomedical Document type: Other Language: en To advance PEM, several key directions should be pursued. Large-scale, multicenter studies are needed to assess the effectiveness of precision interventions in emergency settings, providing robust evidence for their impact on patient outcomes. Investment in technological innovations is crucial to developing rapid and accurate diagnostic tools that align with the fast-paced nature of emergency care . Additionally, integrating precision medicine into EM curricula will equip clinicians with the necessary skills to utilize these tools effectively. Establishing ethical guidelines and policies that address data privacy and consent issues is essential to ensuring patient trust and compliance with regulatory standards. Finally, fostering interdisciplinary collaboration will help bridge the gap between technological capabilities and clinical application, enabling a more seamless integration of precision medicine into emergency care . Section title: Conclusions Educational score: 3.902811288833618 Domain: biomedical Document type: Review Language: en PEM is an emerging field with the potential to significantly improve patient care in emergency settings. These advanced diagnostic tools, including genomic profiling, ML algorithms, and point-of-care technologies, highlight the significant potential of PEM to transform emergency care. While the current literature is limited, the studies reviewed highlight promising applications and underscore the importance of addressing barriers to implementation. By fostering interdisciplinary collaboration, investing in education and technology, and developing supportive policies and ethical guidelines, the integration of precision medicine into emergency care can be realized, ultimately enhancing patient outcomes in acute settings. | Other | biomedical | en | 0.999994 |
PMC11698537 | Section title: Introduction Educational score: 4.176023483276367 Domain: biomedical Document type: Study Language: en Hepatoblastoma is the most common primary malignant hepatic tumor in children. Hepatoblastoma accounts for 79% of liver cancers in children under the age of 15 but only makes up one percent of all pediatric cancers . Hepatoblastoma typically presents asymptomatically with an enlarging abdominal mass, elevated alpha-fetal protein (AFP), and less commonly with anorexia, weight loss, and pain . Some cases have reported the production of ectopic adrenocorticotropic hormone (ACTH), parathyroid hormone-related peptide (PTHRP), and beta-human chorionic gonadotropin (hCG), presenting with a paraneoplastic presentation of precocious puberty, which is speculated to be related to the ectopic beta-hCG secretion . Section title: Introduction Educational score: 3.8803186416625977 Domain: biomedical Document type: Other Language: en Precocious puberty is defined as early signs of sexual development in children. The age of onset of precocious puberty is defined as eight in female patients and nine in male patients. In male patients, signs and symptoms of precocious puberty include penile and testis enlargement, pubic or axillary hair growth, deepening of voice, and development of body odor . In female patients, this precocious puberty would present as early breast development, axillary hair growth, menstruation, and rapid height growth . The exact mechanism by which hepatoblastoma causes precocious puberty is still unknown. However, reports of this rare presentation have been increasing over the last three decades as indicated by the increased number of reported cases. However, delays in diagnosis as with our patient are still prevalent, which indicates a need to highlight this presentation for diagnostic application. Section title: Case presentation Educational score: 3.879009246826172 Domain: clinical Document type: Clinical case Language: en We present a two-year-old male patient with persistent abdominal and genital pain for three months. His weight was 25.4 kg, and his height was 105 cm, both of which are above the 99th percentile for his age group. A physical exam revealed Tanner stage three pubic hair, a mature-appearing phallus, a large rugated scrotal sac, and deepened voice. Laboratory studies revealed normal liver function, ACTH, and cortisol levels. Testosterone was noted as 666 ng/dL (normal <9 ng/dL), dehydroepiandrosterone (DHEA) sulfate was 16 mcg/dL (normal <15), androstenedione was 50 ng/dL (normal <22), 17-hydroxyprogesterone was 256 ng/dL (normal <134), and beta-hCG was 72 mIU/mL (normal <50). Section title: Case presentation Educational score: 3.831439256668091 Domain: biomedical Document type: Clinical case Language: en An abdominal X-ray revealed course calcifications within the right upper quadrant . Abdominal ultrasound revealed a right upper quadrant soft tissue mass measuring 8.1 x 7.9 x 7.2 cm, which contained hyperechoic shadowing calcifications and internal vascularity . CT of the chest, abdomen, and pelvis revealed a large heterogeneously enhancing right suprarenal mass measuring approximately 10.1 x 8.7 x 8.4 cm with calcifications and surrounding the intrahepatic inferior vena cava (IVC) and abutting the right hepatic vein . Section title: Case presentation Educational score: 4.188225269317627 Domain: biomedical Document type: Clinical case Language: en A definitive diagnosis of hepatoblastoma was made via ultrasound-guided biopsy. The tumor was staged as a Pretext 1. It encompassed the right posterior section of the liver, without caudate or additional hepatic foci, that partially encased the right hepatic vein and intrahepatic IVC. There was no evidence of tumor rupture, portal vein involvement, or distant metastasis. At this time, AFP was measured as 113,601 ng/mL (normal 0.5-7.9 ng/mL). Histological evaluation demonstrated epithelial hepatoblastoma with three subtypes, which included fetal subtype, embryonal subtype, and small-cell undifferentiated cells . Furthermore, membranous staining highlighted the fetal and embryonal subtypes, while the nuclear was positive in the embryonal subtype in beta-catenin staining . Lastly, microphotographs demonstrated that the mesenchymal portion of the tumor consisted of osteoid and osteoid-like tissue and that the calcifications had melanocytes as part of their composure . Section title: Case presentation Educational score: 3.8812530040740967 Domain: clinical Document type: Clinical case Language: en The tumor was determined to be resectable, so the patient underwent a right hepatic lobectomy with right retroperitoneal nodal sampling. Final pathology identified a 10.5 x 8.5 x 5.0-cm hepatoblastoma that consisted of mixed epithelial (fetal) and mesenchymal (small-cell undifferentiated pattern (5%)) types and mitotically active with teratoid features. Parenchymal margins were negative for tumor, and lymphovascular invasion was not identified. Post-operatively, the patient recovered well and was discharged home on post-operative day nine. After resection, AFP levels decreased to 8,563.0 ng/mL. The patient went on to receive two cycles of cisplatin therapy. After his first round of cisplatin, his AFP dropped to 28.7 ng/mL, and after the second round, his AFP was within normal limits at 5.5 ng/mL. Beta-hCG remained within normal limits after treatment, and a repeat CT scan showed no evidence of pulmonary metastasis or local disease recurrence. The patient was determined to be in remission, and therefore, his port was removed. Section title: Discussion Educational score: 4.080666542053223 Domain: biomedical Document type: Study Language: en There have been approximately 40 reported cases of hepatoblastoma presenting as precocious puberty . While the true mechanism by which hepatoblastoma leads to the presentation of precocious puberty is still unknown, there are several theories that speculate on the etiology of this relationship. The two potential hypotheses for the paraneoplastic manifestation of precocious puberty secondary to hepatoblastoma are the following: (1) beta-hCG produced by the tumor stimulates Leydig cells to produce testosterone and (2) beta-hCG’s structural similarity to luteinizing hormone and follicle-stimulating hormone leads to direct testosterone secretion in a gonadotropin-releasing hormone-independent manner . It is imperative to note that all reported cases of virilizing hepatoblastoma were seen in patients who presented with elevated beta-hCG levels, highlighting the central role that it has in the development of this presentation . Section title: Discussion Educational score: 3.96301531791687 Domain: biomedical Document type: Study Language: en Early studies suggested that virilizing hepatoblastoma carried worse outcomes compared to non-virilizing, but more recent studies report positive prognosis with long-term survival following surgery and chemotherapy, as seen in our patient . The majority of reported cases were recorded over three decades ago and therefore fail to reflect the progress that has been made in diagnostic, imaging, and treatment modalities, which have the potential to facilitate better outcomes within this population. In the 1970s, the cure rate was around 30%, but the development of better neoadjuvant chemotherapy and surgical resection has increased this value to 70% . This highlights a need for further studies that evaluate potential differences in prognostic outcomes and mortality between virilizing and non-virilizing hepatoblastomas. Section title: Discussion Educational score: 4.0399885177612305 Domain: biomedical Document type: Review Language: en The surgical management of hepatoblastomas remains complex and subject to ongoing debate. While upfront resection via laparotomy at the time of diagnosis has historically been the standard approach, recent advancements have led to the development of risk stratification systems to guide treatment decisions. Leaders of the four cooperative trial groups (SIOPEL, Children’s Oncology Group, the German Society for Paediatric Oncology and Haematology, and the Japanese Study Group for Paediatric Liver Tumours) developed a risk stratification system that divides patients into four risk groups: very low risk (group A), low risk (group B), intermediate risk (group C), and high risk (group D) . These groups are determined with consideration of the PRETEXT group, a radiologic system that describes the extent of a liver tumor before treatment, age at diagnosis, AFP level, and the presence of a PRETEXT annotation factor . Section title: Discussion Educational score: 3.9312620162963867 Domain: biomedical Document type: Review Language: en Tumors that are characterized as low risk are resected at the time of diagnosis. However, for tumors that do not fall into this category, the determination of surgery is less straightforward. Surgical intervention is determined after a thorough evaluation of imaging and after neoadjuvant therapy, with general recommendations suggesting that upfront resection be performed only when segmentectomy or nonextended hemihepatectomy with at least 1 cm margins is possible on middle hepatic vein and/or main portal vein division, and there is no concern for macrovascular involvement . However, there is still much debate on whether complete resection is the gold standard, what margins are acceptable, and how/when to manage metastasis. Section title: Conclusions Educational score: 3.9801790714263916 Domain: biomedical Document type: Other Language: en The presentation of precocious puberty in hepatoblastoma remains an intriguing paraneoplastic phenomenon, with elevated beta-hCG levels being a key factor in its manifestation. Although virilizing hepatoblastoma is a rare presentation, the growing frequency of reports indicates that there is a need for the incorporation of this presentation as part of the work-up and diagnosis of precocious puberty presentations. There is an increased need to share this presentation with multidisciplinary providers, such as general pediatricians, endocrinologists, and oncologists, to prevent delays in diagnosis, as was seen in this patient, and to treat the underlying cancer. Section title: Conclusions Educational score: 3.997061014175415 Domain: biomedical Document type: Review Language: en As surgical management continues to evolve, the adoption of sophisticated risk stratification systems, like those pioneered in the Paediatric Hepatic International Tumour Trial, represents a significant step forward in personalizing treatment strategies. The debate surrounding optimal surgical approaches, whether upfront resection or the timing and extent of surgery following neoadjuvant therapy, remains active. Continued refinement of these protocols, alongside comprehensive studies comparing outcomes across risk categories, will be crucial in enhancing the quality of life for affected patients. | Study | biomedical | en | 0.999996 |
PMC11698539 | Section title: Introduction Educational score: 3.651370048522949 Domain: biomedical Document type: Review Language: en In recent decades, women have achieved substantial progress in entering the medical profession. Notably, in 2017, women medical school matriculants surpassed their men counterparts for the first time . However, gender disparities persist in science and medicine. Numerous studies have identified a persistent achievement gap between men and women faculty in areas such as research productivity, career advancement, leadership roles, compensation, and scientific recognition . Women researchers often offer distinct viewpoints, such as addressing health concerns specifically related to gender or prioritizing the inclusion of a diverse range of populations. This can result in outcomes that are more equitable and pertinent. The absence of their representation can lead to the continuation of biases and neglect of essential research areas, which ultimately restricts the significance and relevance of the results produced. Section title: Introduction Educational score: 3.997413396835327 Domain: biomedical Document type: Study Language: en Clinical trials are integral to evidence-based medicine and critical for advancing new medical therapies and devices. Leading a clinical trial as a principal investigator (PI) provides physicians with enhanced visibility, national recognition, and opportunities for career progression, including promotions, tenure, and future funding . Despite these benefits, women remain underrepresented as PIs in clinical trials. For example, a study of hip and knee arthroplasty clinical trials found that only two of 192 (1%) PIs were women from January 2015 to December 2021 . Similarly, Nguyen et al. reported that from December 2014 to August 2019, just six of 266 (9.5%) cardiac surgery clinical trials were led by women . Section title: Introduction Educational score: 3.8761963844299316 Domain: biomedical Document type: Study Language: en Although these disparities are well documented in other specialties, the representation of women in genetic clinical trial leadership remains largely unexplored. Investigating the gender distribution of PIs in genetic clinical trials can provide valuable insights into the extent of this gender gap. This study aimed to address the following questions: (1) What proportion of genetic clinical trial PIs are women, and how has this changed over time? (2) Are certain trial characteristics (such as phase, status, funding source, or intervention) associated with women PIs? (3) What is the geographic distribution of genetic clinical trials led by women PIs within the United States? Section title: Materials and methods Educational score: 1.3672782182693481 Domain: biomedical Document type: Other Language: da Study design Section title: Materials and methods Educational score: 4.001335144042969 Domain: biomedical Document type: Study Language: en We performed a thorough analysis of clinical trials using the publicly accessible ClinicalTrials.gov database, managed by the National Institutes of Health (NIH). This platform provides comprehensive data on registered trials, including information such as trial phase, sponsor, submission date, and location. In the United States, it is legally required to register all Phase II, III, and IV trials on ClinicalTrials.gov . To focus on genetic-related clinical trials, we conducted a targeted search using specific Medical Subject Heading terms and keywords such as "genetics", "genetic testing", "gene therapy", "genomic sequencing", and similar terms. All trials found with these search terms were included in the screening process. Section title: Materials and methods Educational score: 0.9117360711097717 Domain: biomedical Document type: Other Language: it Data acquisition Section title: Materials and methods Educational score: 3.9087936878204346 Domain: biomedical Document type: Study Language: en On March 4, 2024, data from clinical trials were extracted in XML format from ClinicalTrials.gov and imported into Microsoft Excel (Microsoft Corporation, Redmond, Washington) for further processing. Our analysis focused on studies initiated in 2007 or later, aligning with the implementation of the US Food and Drug Administration Amendments Act. This legislation requires the registration of all Phase II, III, and IV trials conducted in the United States on ClinicalTrials.gov . Collected information included the trial phases (I, II, III, IV, or unspecified), sources of funding (industry, federal, NIH, or other), the year the trial started, types of interventions (behavioral, drug, device, procedure, etc.), the lead investigator's first name, and details of the trial's location (city, state, country). The US Census Bureau's definitions of Northeast, Midwest, South, and West were used for regional categorization. Section title: Materials and methods Educational score: 0.9680196642875671 Domain: other Document type: Other Language: it PI gender identification Section title: Materials and methods Educational score: 3.9706757068634033 Domain: biomedical Document type: Study Language: en We compiled a list of investigators' first names using their full names and titles. Drawing from methods used in prior studies, we utilized Genderize.io ( https://genderize.io ), a well-known tool for determining gender from first names . Genderize.io predicts gender based on a large dataset of names and their associated probabilities. Each first name was analyzed to provide a predicted gender with a probability value. In accordance with previous studies, names were categorized as man or woman, with a 60% threshold for gender assignment to ensure a balance between accuracy and inclusivity . Mapping PI names to Genderize.io posed several challenges, particularly ambiguous or unisex names. Before entering names into Genderize.io , we manually extracted the first name of each PI from our XML file, which was a time-intensive process. The tool itself relies on probabilistic assignments based on name patterns, leading to inaccuracies for uncommon, culturally specific, or unisex names. Additionally, names with regional or linguistic variations often resulted in low confidence scores. Names with lower probabilities or inconclusive results were excluded. Section title: Materials and methods Educational score: 1.9640095233917236 Domain: biomedical Document type: Other Language: en Selection of clinical trials Section title: Materials and methods Educational score: 4.112456321716309 Domain: biomedical Document type: Study Language: en Our study initially included 9,133 genetic trials conducted in the United States, drawn from the ClinicalTrials.gov database. To narrow our analysis, we selected only trials that had a PI listed and had a defined trial phase as per FDA standards (ranging from Phase I to Phase IV). Trials without a defined phase, those with organizations as PIs, or those with incomplete or unclear PI names were excluded as per previous studies . We focused on trials with a defined phase to ensure consistency and facilitate meaningful comparisons. Phase designation reflects the structured progression of clinical trials, aligning with FDA standards. Including non-phase-based studies could introduce variability, making analysis less reliable, so narrowing the scope helped maintain clarity and comparability. After applying these criteria, 4,112 genetic trials were retained for the final analysis . Section title: Materials and methods Educational score: 1.5020114183425903 Domain: biomedical Document type: Other Language: fr Outcomes Section title: Materials and methods Educational score: 2.596153497695923 Domain: biomedical Document type: Study Language: en Our primary goal was to analyze the percentage of women PIs in genetic clinical trials and how this figure has changed over time. We compared the proportion of women PIs in genetic trials for each year from 2007 to 2024. To ensure accuracy, each trial was included only in the first year it was registered. Section title: Materials and methods Educational score: 2.7541725635528564 Domain: biomedical Document type: Study Language: en In addition, our secondary objectives were to examine the geographic distribution of woman PIs across the United States and investigate potential associations between trial characteristics and women PIs. Specifically, we looked at the proportion of women PIs across four key trial factors: trial phase, study status, funding source, and type of intervention. Section title: Materials and methods Educational score: 1.9083342552185059 Domain: biomedical Document type: Study Language: en Statistical methods Section title: Materials and methods Educational score: 4.042924880981445 Domain: biomedical Document type: Study Language: en We presented the basic characteristics of the trials using frequencies and percentages for categorical variables such as geographic region, study phase, funding source, study status, and trial year. Fisher's exact test was used to assess the association between gender and categorical trial attributes, such as geographic region, study phase, funding source, and study status. This method was chosen because it provides accurate results for categorical data, even when some categories have low frequencies, as observed in certain subsets of our data. By applying this test, we ensured a robust analysis of gender differences across trial characteristics, maintaining the validity of our findings. Drawing from methodologies used in prior research, we employed univariate linear regression to analyze trends in the annual percentage of woman PIs . We used heat maps with color gradients to visualize geographic variation. All statistical analyses were conducted using RStudio software version 2023.12.1 (Posit, Boston, Massachusetts), with statistical significance set at p < 0.05. Mapping was performed using QGIS 3.36.0. Section title: Results Educational score: 1.489465355873108 Domain: biomedical Document type: Other Language: en The proportion of women PIs over time Section title: Results Educational score: 2.578774929046631 Domain: biomedical Document type: Study Language: en The overall number of women serving as PIs was 1,552 out of 4,112 (37.7%) leadership roles held by women. This proportion fluctuated over the study period but showed no consistent upward or downward trend (p = 0.35, R 2 = 0.054). The number of women leading clinical trials ranged from seven out of 24 (29.2%) in 2008 to a peak of 17 out of 29 (58%) in 2010 before leveling off to 573 out of 1,712 (33%) in 2024, as outlined in Table 1 and Figure 2 . Section title: Results Educational score: 1.2770007848739624 Domain: other Document type: Other Language: en Women's representation and trial characteristics Section title: Results Educational score: 3.919421672821045 Domain: biomedical Document type: Study Language: en The distribution of trial phases showed significant differences between men and women PIs . Trials with no applicable phase had the highest representation of women leaders, with 604 out of 1,552 (38.9%), compared to 666 out of 2,560 (26%) for men leaders. For trials with specified phases, Phase II had the highest representation of women leaders, with 393 out of 1,552 (25.3%), whereas Phase IV had the lowest, with 82 out of 1,552 (5.3%) of women PIs. Similarly, the highest percentage of men PIs was in Phase II, with 821 out of 2,560 (32.1%) (Table 2 ). Section title: Results Educational score: 3.611564874649048 Domain: biomedical Document type: Study Language: en There was also a statistically significant difference in trial status between men and women PIs . A higher proportion of women PIs led active or recruiting trials, with 516 out of 1,552 (33.2%) compared to 709 out of 2,560 (27.7%) for men. Conversely, more men PIs led discontinued trials, with 439 out of 2,560 (17.1%) compared to 193 out of 1,552 (12.4%) for women PIs (Table 1 ). Section title: Results Educational score: 2.545715093612671 Domain: biomedical Document type: Study Language: en There was a statistically significant difference in funding sources between men and women PIs (p = 0.003). Women PIs received a higher percentage of federal funding, with 24 out of 1,552 (1.5%), compared to 17 out of 2,560 (0.6%) for men PIs. Additionally, women PIs had a higher percentage of studies funded by other sources, with 1,045 out of 1,552 (67.3%), compared to 1,670 out of 2,560 (65.2%) for men PIs. In contrast, a slightly higher percentage of men PIs received industry funding at 695 out of 2,560 (27.1%), compared to 386 out of 1,552 (24.9%) for women PIs (Table 2 ). Section title: Results Educational score: 3.8541958332061768 Domain: biomedical Document type: Study Language: en There was a significant difference in the distribution of intervention types between men and women PIs . Women PIs led a larger proportion of studies involving behavioral interventions, with 240 out of 1,552 (15.5%), and other interventions with 218 out of 1,552 (14%), compared to their men counterparts, who had 196 out of 2,560 (7.7%) and 222 out of 2,560 (8.7%), respectively. On the other hand, men PIs had a higher proportion of studies involving genetic interventions, with 111 out of 2,560 (4.3%), and drug interventions, with 1654 out of 2,560 (64.6%), compared to 44 out of 1,552 (2.8%) and 841 out of 1,552 (54.2%) for woman PIs (Table 2 ). Section title: Results Educational score: 1.476775050163269 Domain: biomedical Document type: Other Language: en Geographic distribution of women PIs Section title: Results Educational score: 3.0187156200408936 Domain: biomedical Document type: Study Language: en There was no significant difference in the geographic distribution of trials led by men and women PIs (p = 0.062). The proportion of women PIs was relatively similar across US Census regions to that of their male counterparts. The states with at least 10 trials that had the highest proportions of women PI were New Mexico (7 of 10, 70%), the District of Columbia (33 of 66, 66%), Virginia (15 of 30, 50%), and Nebraska (7 of 14, 50%). Conversely, the lowest proportions of woman PIs were found in Kentucky (2 of 16, 13.3%), Utah (4 of 26, 15.4%), and Arizona (30 of 160, 18.9%) (Table 3 ) . Section title: Discussion Educational score: 4.134445667266846 Domain: biomedical Document type: Study Language: en Clinical trial leadership is a prestigious role for academic physicians, offering opportunities for increased visibility, career advancement, and access to future funding. It also allows physicians to make substantial contributions to the medical field and improve patient outcomes. The representation of women in leadership roles within genetic clinical trials has not been thoroughly studied or characterized. Our findings revealed that while the proportion of women leading clinical trials fluctuated over time, there was no consistent upward or downward trend. Representation ranged from a low of seven out of 24 (29.2%) in 2008 to a peak of 17 out of 29 (58%) in 2010 before leveling off to 573 out of 1,712 (33%) in 2024. Notably, women surpassed men as PIs during only two years of the study period, making up only 1,552 out of 4,112 (37.7%) of the entire PIs of clinical trials. Women PIs were more likely to lead studies focusing on behavioral and other interventions, whereas men PIs led a higher proportion of genetic and drug trials. Additionally, women PIs received more funding from other sources, while men PIs were more likely to secure industry funding. These findings underscore the need for continued efforts to address gender disparities in clinical trial leadership and highlight the importance of developing strategies to promote equity in this field. Achieving sustained progress will require targeted policies, mentorship opportunities, and collaboration to create an inclusive research environment that supports diverse leadership. Section title: Discussion Educational score: 3.835731029510498 Domain: biomedical Document type: Study Language: en Since 2007, there have been more than two times as many clinical trials led by men as women in genetics. The proportion of women leading clinical trials showed fluctuations over time but remained stagnant between 2007 and 2024, with women comprising 33% of PIs in both years. This is not consistent with women's representation as PIs in other medical specialties . For instance, Burkhart et al. reported that the proportion of women leading orthopedic clinical trials increased from 13% in 2007 to 22% in 2022 . One possible explanation for this discrepancy is that genetics began with a greater baseline of female PIs in 2007, which lessened the perceived urgency of equity initiatives. This early lead may have resulted in fewer measures focused on improving representation, as opposed to other fields that benefitted from focused campaigning to address disparities. Section title: Discussion Educational score: 4.126165390014648 Domain: biomedical Document type: Study Language: en Furthermore, genetics may have received less institutional push to enhance leadership diversity, resulting in stagnation over time. Even though there was a higher proportion of women PIs in genetic trials as compared to other medical specialties, the lack of growth is concerning. Certain specialties have demonstrated substantial growth in women's representation, with women comprising the majority of clinical trial PIs in some cases. For example, the proportion of women PIs in Phase III gynecologic oncology trials increased markedly from 10% in 2010 to 60% in 2020 . This suggests there is still substantial room for improvement. Women exceeded men as PIs in genetic clinical trials only in 2008 and 2010, suggesting isolated advances rather than a sustained trend toward gender parity in this discipline. These brief periods of female predominance might be attributed to external influences such as specific regulations, financial campaigns, or cultural transformations that emphasized women's leadership in science during those years. However, their brief existence shows that such attempts were either not sustained or insufficient to overcome larger systemic obstacles. To increase the number of women PIs in genetics, institutions and professional organizations should implement mentorship programs focused on career development and provide networking opportunities tailored to their needs. Continuous evaluation of clinical trial leadership is crucial as the presence of women in academic leadership roles within genetics evolves. Understanding these trends can guide the development of effective strategies to reduce gender disparities and promote equity in the field. Section title: Discussion Educational score: 4.129263877868652 Domain: biomedical Document type: Study Language: en Our analysis revealed that women were more likely to receive federal or other funding, whereas men were predominantly funded by industry sources. This aligns with previous studies indicating that men receive a disproportionately larger share of industry funding. For instance, a 2016 study found that women academic orthopedic surgeons received only 29% of industry payments, even after adjusting for factors such as faculty rank, H-index, and subspecialty selection . These funding disparities are not isolated to orthopedics but are widespread across medical specialties for women surgeon-scientists . A potential explanation for this inequity is that 75% of physicians with financial ties to biomedical companies are men . Funding differences between male and female PIs may impact trial scope and results. Women PIs' dependence on federal and "other" funding sources indicates a preference for fundamental or exploratory research, which may have less immediate economic appeal but contributes to scientific progress. Men PIs, on the other hand, may receive more industry funding, allowing them to conduct larger, commercially motivated investigations. These disparities may influence the types of research conducted and how findings are translated into clinical practice, emphasizing the importance of fair financing to promote a balanced research environment. Section title: Discussion Educational score: 4.120786666870117 Domain: biomedical Document type: Study Language: en Interestingly, our findings differ slightly from those of Burkhart et al., who reported no significant differences in the distribution of men and women across trial phases, statuses, or funding sources in orthopedics . The distinctions from Burkhart et al. might stem from the distinctive characteristics of genetics research, encompassing a variety of interventions such as gene therapy and diagnostics, which draws a wider array of researchers and funding opportunities. Genetics trials may additionally provide greater chances for exploratory or federally supported studies, where there is a higher representation of women, in contrast to orthopedics, which is generally more influenced by industry and consistent in trial attributes. Furthermore, our results showed an increased number of female PIs in Phase II trials, which might be attributed to the collaborative character of these investigations, which involve input from interdisciplinary teams and are consistent with leadership styles that emphasize cooperation and communication. Furthermore, Phase II trials frequently obtain funding from smaller organizations or agencies that encourage diversity, possibly increasing prospects for women-led research. These trials are usually carried out in academic or research-focused institutions, where women are more likely to be represented than in industrial settings, and they benefit from mentorship and support networks. Furthermore, the combination of clinical practice and research in Phase II studies may appeal to women who want to combine patient care with medical advancements. Additionally, our analysis demonstrated that women PIs led a higher proportion of studies focused on behavioral and other interventions, while men PIs were more involved in drug-related trials. This observation is consistent with other studies showing that women are more likely to lead observational studies . Section title: Discussion Educational score: 3.906792640686035 Domain: biomedical Document type: Study Language: en Understanding the distribution of PIs across various trial phases and intervention types is critical for informing research strategies, guiding funding allocation, and shaping policy decisions to address gender disparities in clinical trial leadership. The lack of women in higher-phase trials, such as Phase III and IV, may stem from obstacles related to resources and career growth. These trials demand significant funding and leadership experience, which tend to be more readily available to men due to systemic issues such as implicit bias in funding, limited mentorship, and fewer opportunities for leadership. Such challenges restrict women's capacity to oversee extensive, resource-heavy studies, thereby sustaining the gender disparity in advanced clinical research. Section title: Discussion Educational score: 3.89894700050354 Domain: biomedical Document type: Other Language: en A diversified strategy is needed to address the differences in clinical trial PIs between men and women in the field of genetics. Mentorship programs should be established by institutions and professional associations to assist and guide women who wish to pursue careers as PIs in genetics. To ensure fair representation, department heads must aggressively advance women faculty members to prominent roles in leadership and research. Grant programs aimed at women researchers should be created and extensively publicized in order to further address these inequities. Making successful women academics more visible through prizes, press attention, and high-profile conference speaking engagements can motivate and inspire others to follow in their footsteps. Equal funding distribution should also be required by institutional and governmental policy reforms, guaranteeing that women researchers have the tools necessary to conduct and complete clinical studies. These could also be integrated with efforts to minimize implicit bias in hiring and funding choices, guaranteeing women equal chances. Ultimately, instituting transparency standards regarding gender representation in leadership roles could ensure accountability for institutions while offering metrics for assessing progress toward equity. When these strategies are used together, they can foster a more equitable and inclusive research setting. Section title: Discussion Educational score: 4.122922897338867 Domain: biomedical Document type: Study Language: en Our analysis has several limitations that should be considered when interpreting the findings. First, our reliance on data from ClinicalTrials.gov , a global registry for clinical trials, introduces a potential bias, as trials not requiring FDA regulation are not mandated to register, potentially underrepresenting international studies. Second, the use of Genderize.io to determine the gender of PIs carries inherent risks of misclassification, particularly for names with ambiguous or culturally diverse origins. Although we excluded names with lower prediction probabilities to improve accuracy, this approach may have inadvertently removed some correctly classified individuals, potentially affecting the representativeness of our findings. Additionally, our analysis was limited to gender as the sole diversity variable, excluding other important dimensions of social identity such as race, ethnicity, and socio-economic background. Finally, we did not provide a detailed breakdown of subspecialties within genetic trials or account for other potential confounding variables, such as trial initiation year, that may influence gender representation. Future studies should address these limitations by incorporating broader datasets, expanding diversity metrics, and utilizing software that can more accurately determine the gender of a name or directly contacting PIs to determine accurate gender to capture the intersectionality of social identity factors and their impact on clinical trial leadership. Section title: Conclusions Educational score: 4.023432731628418 Domain: biomedical Document type: Study Language: en Our findings highlight significant gender disparities in clinical trial leadership within genetics, with women underrepresented as PIs and showing limited progress over time. While women were more likely to receive federal or other funding, men predominantly secured industry funding, reflecting broader inequities seen across medical specialties. Despite some fields achieving notable growth in women's representation, the standstill in genetics underscores the need for targeted interventions. Addressing these disparities will require a comprehensive approach, including mentorship programs, equitable funding policies, increased visibility for women researchers, and active promotion of women into leadership roles. By fostering an inclusive research environment and addressing funding imbalances, we can work toward achieving greater equity in clinical trial leadership, ultimately enhancing the diversity and impact of genetic research. | Review | biomedical | en | 0.999997 |
PMC11698540 | Section title: Introduction Educational score: 1.7429560422897339 Domain: biomedical Document type: Other Language: en Tobacco is a botanical species indigenous to South America. Tobacco has been utilized not only to smoke but also for chewing, ingestion, topical application, and ocular administration throughout its history, yet smoking remains the most enduring method . With the acknowledgment of its pleasurable attributes, its utilization has proliferated significantly . Section title: Introduction Educational score: 3.5568625926971436 Domain: biomedical Document type: Review Language: en The World Health Organization (WHO) defines cigarette addiction as a chronic illness characterized by progression and recurring relapses . This epidemic, spanning centuries, has severe consequences in terms of morbidity and mortality . Annually, more than seven million people worldwide and upwards of 100 thousand people in Turkey die as a result of smoking-related diseases . Considering variables such as the age of smoking initiation, duration of use, daily consumption volume, and quality of the product used, it has been observed that as exposure to the dose increases, smoking-related diseases and mortality increase . Section title: Introduction Educational score: 2.192723035812378 Domain: biomedical Document type: Other Language: en The age of starting smoking varies between genders, with females typically beginning smoking at a slightly later age than males. The prevalence of smoking is significantly higher among males than females. The male-to-female ratio is highest in Egypt and lowest in Poland and Uruguay . Individuals in Asia and Africa tend to initiate smoking at a later age compared to those in Europe and Latin America . Turkey is one of the 10 countries with the highest smoking rates in the world . According to 2016 data on current smoking rates in Turkey, approximately two out of every five males, one out of every eight females, and an average of one out of every four individuals in the general population are reported to be smokers . Section title: Introduction Educational score: 3.9467520713806152 Domain: biomedical Document type: Review Language: en The toxins in cigarette smoke permeate the bloodstream and harm nearly every organ in the body . Smoking is linked to the onset of chronic obstructive pulmonary disease (COPD), as well as chronic respiratory diseases, such as asthma and interstitial lung disease . Smoking is critical due to its status as the leading preventable factor associated with cardiovascular diseases . The risk of myocardial infarction is directly correlated with the quantity of smoking. Over half of the deaths attributed to coronary artery diseases (CADs) are sudden in nature, and the cessation of tobacco can lead to a decreased risk of sudden death . Section title: Introduction Educational score: 3.59928035736084 Domain: biomedical Document type: Review Language: en Quitting smoking can diminish smoking-related diseases and fatalities, decelerate the rate of disease progression, and augment life expectancy . Smoking cessation therapies are extensively utilized, and smokers now have more access to smoking cessation methods than ever before. Smokers who receive smoking cessation treatment, a combination of behavioral interventions and medication, are five times more likely to succeed in quitting compared to those who attempt to quit independently . Section title: Introduction Educational score: 3.9338982105255127 Domain: biomedical Document type: Review Language: en Numerous studies report disparate findings regarding the factors influencing the success of smoking cessation. Prominent factors include motivation and determination, sociodemographic attributes, addiction severity, psychological and environmental influences, and comorbidities . Approximately 70-80% of tobacco users desire to quit, with approximately one-third attempting to quit independently each year. However, less than 10% succeed in their cessation endeavors . Two approaches have proven beneficial in the endeavor to quit smoking. These approaches encompass motivational interviewing and pharmacotherapy, incorporating behavioral therapy techniques . Section title: Introduction Educational score: 3.656282424926758 Domain: biomedical Document type: Other Language: en In their routine clinical practice, physicians ought to inquire of every patient, irrespective of the reason for the visit, regarding their smoking status, the quantity of smoking, and their contemplation of cessation. Additionally, healthcare professionals should support those wishing to quit and conduct motivational interviews with those not yet ready. Research has demonstrated that the mere act of physicians delicately inquires patients' smoking habits and issuing admonitions prompts contemplation toward cessation, culminating in a success rate of 1-3% in quitting . Section title: Introduction Educational score: 3.112947463989258 Domain: biomedical Document type: Other Language: en Motivational interviewing is based on identifying and exploring the underlying issues pertinent to smokers, aiming to effect behavioral change. The dynamic is grounded in a collaborative and amicable partnership, diverging from the traditional consultant-client paradigm . Randomized controlled trials have shown that motivational interviewing for smoking cessation yields superior efficacy compared to dispensing brief advice . Section title: Introduction Educational score: 1.7626607418060303 Domain: biomedical Document type: Other Language: en The pervasive recurrence of cessation failures and relapses underscores the imperative for smokers to pursue professional assistance. Section title: Introduction Educational score: 3.349470853805542 Domain: biomedical Document type: Study Language: en In our study, we administered motivational interviews for smoking cessation to a specific cohort comprising both patients and healthy smokers. Our objective was to demonstrate the impact of motivational interviewing on smoking cessation. Furthermore, we investigated the influence of medical conditions and individual traits on the efficacy of motivational interviewing for smoking cessation. Section title: Materials and methods Educational score: 1.4882196187973022 Domain: biomedical Document type: Other Language: en Participants and study design Section title: Materials and methods Educational score: 4.1205596923828125 Domain: biomedical Document type: Study Language: en This prospective study was conducted with smokers who presented at the pulmonology and cardiology outpatient clinic. The study encompassed 100 participants each from asthma, COPD, and healthy individuals with smoking (HIWS) habit cohorts who were admitted to the pulmonary outpatient clinic, along with 100 individuals diagnosed with CAD who attended the cardiology outpatient clinic during the period spanning from April 20, 2023, to July 20, 2023. Our study enrolled healthy individuals of any gender, aged 18 years or older, who had smoked for at least 15 years. Individuals with deficient medical documentation, immune system disorders, malignancy, a second chronic disease other than COPD/asthma/CAD, and a smoking history of less than 15 years were not included in the study. Routine laboratory tests, electrocardiography (ECG), pulmonary function testing (PFT), chest radiography, Fagerstöm nicotine dependence test (FTND), and hospital-scale anxiety-depression test (HAD-A/HAD-D) were performed on patients. In addition, low-dose chest computed tomography (CT) was administered for lung cancer screening among individuals aged over 50 years of age and with a smoking history exceeding 20 pack years. Section title: Materials and methods Educational score: 3.9129750728607178 Domain: biomedical Document type: Study Language: en FTND serves as a standardized instrument for evaluating the degree of physical nicotine dependence. Uysal et al. adapted the FTND into Turkish, confirming its validity and reliability through a study conducted in 2004 . The assessment comprises six items, yielding a cumulative score from 0 to 10. In this study, an FTND score of 9 or higher defined very high dependence, with categorizations ranging from very low (0-2), low (3-4), moderate (5-6), and high levels of dependence levels. Section title: Materials and methods Educational score: 3.18841290473938 Domain: biomedical Document type: Study Language: en The HAD scale was devised to detect anxiety and depression among patients grappling with physical diseases . The scale comprises a total of 14 items. Of these, seven items measure symptoms indicative of anxiety, while the remaining seven assess symptoms indicative of depression. Following studies conducted in Turkey, the cut-off score for the anxiety subscale (HAD-A) was set at 10, and for the depression subscale (HAD-D), it was established as 7. Section title: Materials and methods Educational score: 1.4313400983810425 Domain: biomedical Document type: Other Language: en Smoking Cessation Motivational Interview Section title: Materials and methods Educational score: 3.3432741165161133 Domain: clinical Document type: Study Language: en Interviews were conducted by pulmonologists. The pulmonologists gave a concise lecture covering topics such as nicotine addiction, nicotine withdrawal syndromes, the adverse effects of smoking, the advantages of quitting, strategies to manage weight gain, and techniques to navigate trigger situations. Patients were scheduled for outpatient clinic follow-up appointments at the conclusion of the first month, the third month, and the sixth month. In addition, brief support and behavioral interviews were conducted with the patients via telephone weekly for the first month, followed by sessions every 15 days after that. During the follow-up visit, the patient's smoking cessation status was assessed. Patients who were unable to quit smoking received another brief support session. During each visit, discussions averaging about 10 minutes centered on motivational factors, identification of triggers, management of weight gain, and utilization of medications. Section title: Materials and methods Educational score: 0.9690467119216919 Domain: other Document type: Other Language: it Ethical approval Section title: Materials and methods Educational score: 1.2440401315689087 Domain: biomedical Document type: Other Language: en This study was approved by the hospital institution ethics committee . Consent forms were obtained from all patients. Section title: Materials and methods Educational score: 1.4600969552993774 Domain: biomedical Document type: Other Language: en Statistical analysis Section title: Materials and methods Educational score: 3.855884313583374 Domain: biomedical Document type: Study Language: en The statistical analysis utilized the IBM SPSS Statistics software, version 17.0 (IBM Corp., Armonk, USA). The Kolmogorov-Smirnov test was used to assess the normal distribution of the data, while the ANOVA test was employed to evaluate the homogeneity of the data. Medians with 25-75th percentiles were reported as continuous variables, discontinuous variables were presented as frequencies and percentages, and a chi-square test was applied. Mann-Whitney U and Kruskal-Wallis H tests evaluated median comparisons. Statistical significance was determined at a P-value below 0.05. Section title: Results Educational score: 1.8477859497070312 Domain: biomedical Document type: Study Language: en Demographic characteristics and laboratory findings Section title: Results Educational score: 3.848792791366577 Domain: biomedical Document type: Study Language: en The study included 400 smokers, comprising 100 individuals with asthma, 100 with COPD, 100 healthy smokers, and 100 patients with CAD, without gender-based differentiation. The median age of the patient cohort was 52 (44-58) years. Among the 400 patients, 177 (44.2%) were female, with a median age of 50 (42-58) years, and 223 (55.8%) were male, with a median age of 53 (46-59) years. The median body mass index was 29.75 (26.51-31.23) kg/m 2 . Section title: Results Educational score: 2.564735174179077 Domain: biomedical Document type: Study Language: en The median age of starting smoking was 18 (15-20) years, and the smoking pack-year history was 33 (25-40). All demographic data, smoking history, laboratory findings, FTND, HAD-A, and HAD-D for all study populations and the patients in the four subgroups are depicted in Tables 1 - 2 . Section title: Results Educational score: 1.2296150922775269 Domain: biomedical Document type: Other Language: it Smoking cessation data Section title: Results Educational score: 3.8528964519500732 Domain: biomedical Document type: Study Language: en According to smoking cessation, 85 (21.3%) patients quit smoking at the end of the first month. It was 55 (13.8%) at the end of the third month and 42 (10.5%) at the end of the sixth month. Within all subgroups, the smoking cessation ratios were higher at the end of the first month than in the third and sixth months, with the asthma subgroup exhibiting a particularly notable increase. Although, by the end of the sixth month, smoking cessation rates declined across all subgroups, the most notable smoking cessation rate was observed among the asthma subgroup, with a ratio of 3.5%, but it was statistically insignificant (Table 3 ). Section title: Results Educational score: 3.9951603412628174 Domain: biomedical Document type: Study Language: en At the end of the sixth month, all variables within the study population, encompassing age, age of smoking initiation, smoking quantity, FTND, HAD-A, and HAD-D, were examined concerning smoking cessation. Upon analyzing these variables, no statistically significant difference was identified between individuals who had ceased smoking and current smokers. Conversely, females (26, 61.9%) demonstrated superior outcomes in smoking cessation compared to males (16, 38.1%). In addition, the majority of individuals who quit smoking had a high dependence on nicotine, but it was statistically insignificant (Table 4 ). Section title: Results Educational score: 4.032083511352539 Domain: biomedical Document type: Study Language: en A linear correlation was observed between the first month of smoking cessation (p=0.007) and smoking pack-year history (p=0.025) (Table 5 ). Furthermore, a significant correlation was found between the third month of smoking cessation and HAD-D (p=0.027). A difference was found between the third month of smoking cessation in median values of smoking pack-year history, but it was not statistically significant (p=0.053) (Table 6 ). Furthermore, a relationship was found between the sixth month of smoking cessation and gender (p=0.015) and smoking pack-year history (p=0.022) (Table 4 ). Females exhibited a higher propensity to cease smoking. As the smoking rate decreased, the smoking cessation rate increased. However, according to smoking cessation, no difference was found between subgroups in the first month (Table 3 ). Section title: Discussion Educational score: 2.6440372467041016 Domain: biomedical Document type: Study Language: en The WHO recognizes smoking as one of the leading preventable health hazards . Numerous methodologies have been devised to aid patients in the endeavor of smoking cessation. In our investigation, we conducted interviews focused on smoking cessation. More than 20% of the smokers subjected to interviews successfully quit smoking by the conclusion of the initial month. It was noted that 50% of these individuals restarted smoking during the subsequent follow-up. The smoking cessation rate among the interviewed cohort was 10.5% by the conclusion of the sixth month. According to gender, the cessation of smoking in the sixth month was significantly higher in females. Section title: Discussion Educational score: 2.2162058353424072 Domain: biomedical Document type: Study Language: en The global estimate of tobacco smokers is approximately 1.3 to 1.5 billion individuals. Turkey is among the 10 nations where one-third of global smokers reside . We investigated the effectiveness of smoking cessation interviews in Turkey, which has a high prevalence of smokers. In this context, such endeavors can contribute to reducing smoking prevalence. The adequacy of our patient cohort led us to anticipate greater clarity in the information obtained. Additionally, we devised strategies to elucidate differences by incorporating various patient cohorts into the study design. Section title: Discussion Educational score: 4.094110488891602 Domain: biomedical Document type: Study Language: en Numerous studies document disparate findings regarding the determinants influencing the efficacy of smoking cessation efforts . Approximately 70-80% of tobacco users desire to quit, with approximately one-third endeavoring to do so independently each year. Nevertheless, the success rate is less than 10% . In a study conducted in Taiwan, it was demonstrated that augmenting one's comprehension regarding the deleterious ramifications of smoking within the context of transtheoretical model (TTM)-based smoking cessation interventions markedly enhanced the endeavor to cease smoking . In an alternative study, the efficacy of the health belief model and the TTM model in smoking cessation was evaluated, determining that both methodologies were effective, albeit with the TTM model demonstrating superior effectiveness . In the study by Sharifirad et al., the smoking cessation rate after a six-month follow-up period was revealed to be 3.3% in the control group and 46.0% in the intervention group. Notably, all components of the TTM model yielded significant outcomes . A meta-analysis study concluded that motivational interviews are effective in quitting smoking . Numerous additional studies have corroborated the effectiveness of motivational interviews as a valuable method for facilitating smoking cessation efforts . In our research, following the smoking cessation interview and regular follow-up sessions, the success rate for smoking cessation was 21% at the end of the first month. At the end of the sixth month, our smoking cessation rate declined to 10.5%. The main reason for this decline could potentially be attributed to a dilution in patient follow-up after the initial month. Section title: Discussion Educational score: 4.082226753234863 Domain: biomedical Document type: Study Language: en In our study, during the initial evaluation at the outpatient clinic, comprehensive inquiries were made regarding the demographic profiles of individuals and smoking histories. The patients were also assessed using respiratory function tests, FNBT, and the HAD-A/HAD-D scales. The data were compared with those at the end of the sixth month. Studies have demonstrated that certain sociodemographic attributes, including male gender, older age, higher education attainment, elevated socioeconomic status, employment status, and having a stable partnership (such as being married or cohabiting), positively influence the success of quitting smoking . Conversely, there are also publications asserting that no discernible gender disparity exists in smoking cessation outcomes . Studies have indicated that varenicline treatment exhibits greater efficacy in facilitating smoking cessation among females compared to males. Conversely, nicotine replacement therapy and bupropion treatment demonstrated a lower success rate in smoking cessation among females relative to males . Enhancing smoking cessation rates among women could be achievable through the implementation of gender-specific studies . One study from China observed variations in smoking behaviors based on gender and rural-urban distinctions . Monsó et al. demonstrated that age, gender, and housing conditions exert a notable influence on smoking cessation outcomes among European participants engaged in smoking cessation programs . Our study gave results that were diverged from those reported in previous studies. In our study, after the sixth month, females exhibited higher smoking cessation rates compared to males. Females had a twofold propensity to quit smoking compared to males. Within the disease categories, the most notable smoking cessation rate was observed within the asthma cohort. This trend could be attributed to the elevated presence of females in the asthma cohort. Section title: Discussion Educational score: 4.028006553649902 Domain: biomedical Document type: Study Language: en Several studies indicate that the duration of tobacco use serves as a pivotal factor in the efficacy of cessation efforts. In the study conducted by Górecka et al., smoking duration emerged as a significant variable influencing the likelihood of successful cessation . In a study conducted in Turkey, it was discovered that individuals who commenced smoking prior to the age of 15 exhibited a markedly reduced likelihood of smoking cessation compared to those who initiated tobacco use later . Likewise, in our study, a correlation was observed between the quantity of tobacco consumed and the cessation status of smoking. However, no significant association was detected between the age of smoking initiation. Numerous studies in the literature assess the correlation between smoking cessation status and FNBT, HAD-A, and HAD-D scores. While some studies have reported a significant relationship, others have not. In our study, a statistically significant relationship was identified between smoking cessation status and HAD-D (in the first and third months of control), but not with FNBT and HAD-A scores. Section title: Discussion Educational score: 3.9790077209472656 Domain: biomedical Document type: Study Language: en Study outcomes vary regarding the impact of chronic disease presence on the efficacy of smoking cessation. The study by Salepçi et al. found that the presence of comorbidities among smokers did not influence their success in quitting . Conversely, Uzaslan et al. found that the participants' health problems positively influenced the success of smoking cessation endeavors . Komiyama et al. reported that the success rate of smoking cessation among COPD patients, psychiatric patients, females, and minors was low . In addition, Perret et al. elucidated the relationship between asthma and smoking in their review . Furthermore, Gratziou et al. demonstrated the importance of an intensive smoking cessation program with regular and prolonged follow-ups for smokers with asthma or COPD. Regular and frequent follow-up visits, particularly within the initial three months, were positively correlated with cessation success . Ludvig et al., in their review, compared smoking cessation success rates among patients with CVD and noted that the success rate during treatment reached up to 25%. However, they also noted that the relapse rates were notably high . A meta-analysis by Taylor et al. highlighted that the success rate could increase to 45% with diligent follow-up and cardiac rehabilitation for patients following acute coronary syndrome . In our study, no difference was observed among disease subgroups (asthma, COPD, HIWS, CVD) regarding smoking cessation. The highest rates of smoking cessation were observed during the initial month of intensive follow-up. Consistent with numerous studies, the smoking cessation rates at six months were 10%. Section title: Discussion Educational score: 1.559439778327942 Domain: biomedical Document type: Other Language: it Limitations Section title: Discussion Educational score: 1.725326657295227 Domain: biomedical Document type: Study Language: en We did not experience any significant limitations in our study. The only limitation was the reluctance of patients to receive regular calls and regular check-ups. Although they liked to have a health check-up and be followed up for health, they had a hard time adapting. Section title: Conclusions Educational score: 4.016526222229004 Domain: biomedical Document type: Study Language: en When we evaluated our study together with other studies, we thought that motivational interviewing was effective in smoking cessation treatment. We interviewed our patients for smoking cessation support, and at the end of the first month, we achieved success in about a quarter of them. At the end of the sixth month, this success rate decreased to around 10%. Considering that patient interviews were made more frequently in the first months, it is suggested that these rates may not change if patient follow-ups are made frequently in other months. Smoking cessation success was higher in the female population than in males. In addition, the smoking cessation rate was higher in the first months in groups with respiratory disease. Throughout the entire study, the asthmatic patient group showed a higher smoking cessation success than the other groups. It is evident that supporting motivational interviewing with psychosocial and quality-of-life support tests would increase smoking cessation. | Other | biomedical | en | 0.999998 |
PMC11698543 | Section title: Introduction Educational score: 4.301061630249023 Domain: biomedical Document type: Clinical case Language: en Hypokalemia-induced rhabdomyolysis caused by primary hyperaldosteronism is a rare occurrence. Primary hyperaldosteronism, also known as Conn's syndrome, is typically due to bilateral adrenal hyperplasia (BAH) or, less commonly, an adrenal adenoma. Hyperaldosteronism leads to sodium retention and potassium excretion. It mostly presents as hypertension, although a minority of patients may experience symptoms of hypokalemia, such as muscle weakness, cramps, and fatigue . A severe decrease in serum potassium levels can disrupt the skeletal muscle vascular dilation system, which results in ischemia and necrosis of the muscle fibers, leading to rhabdomyolysis. Rhabdomyolysis classically manifests as progressive weakness, fatigue, and dark urine due to the release of myoglobin and other toxic intracellular elements such as creatine kinase (CK) and lactic acid. Myoglobin has the potential to cause acute kidney injury (AKI), and in severe cases, rhabdomyolysis can also be fatal. More common causes of rhabdomyolysis include traumatic muscle injuries, exertion due to exercise or seizures, and alcohol abuse . In this case, the patient used a massage gun to relieve the soreness in her legs, the use of which has been reported to result in rhabdomyolysis . However, further investigation revealed a left-sided adrenal adenoma, which, after being surgically removed, led to the resolution of her symptoms, suggesting that the causative factor in this case was hyperaldosteronism, leading to hypokalemia. Section title: Case presentation Educational score: 3.599195718765259 Domain: clinical Document type: Clinical case Language: en We present the case of a 37-year-old female with a prior history of hypertension, diabetes, and schizoaffective disorder. She was also a known case of chronic hypokalemia secondary to primary hyperaldosteronism. She presented to the Emergency Department (ED) with complaints of bilateral lower extremity weakness for seven days, along with fatigue. She had been using a massage gun extensively to alleviate the discomfort in her legs. A day before her presentation, she experienced extreme weakness and was unable to hold up her weight and fell on her lower back. She denied other symptoms like fever, dizziness, abdominal pain, cough, shortness of breath, or headache. However, a few nights ago, she experienced chest discomfort without pain and was unable to fall asleep. Section title: Case presentation Educational score: 3.449493408203125 Domain: clinical Document type: Clinical case Language: en A year ago, during her pregnancy, she had multiple presentations with similar symptoms of weakness. Her lab results showed raised aldosterone levels (113 ng/dL, reference values < 3.0-23.2 ng/dL), decreased plasma renin levels (0.59 pg/mL/hour, reference values ≤33.2 pg/mL/hour), and decreased serum potassium levels (3.0 mmol/L, reference values 3.5-5.1 mmol/L), for which she received both IV and oral potassium chloride (KCl). She was discharged with a prescription for KCl supplements, which she had run out of a week prior to her ED visit. She had not obtained a refill due to her upcoming appointment with an endocrinologist. Section title: Case presentation Educational score: 3.6751275062561035 Domain: clinical Document type: Clinical case Language: en Blood work at her current presentation showed an initial serum potassium level of 2.6 mmol/L and a raised CK level (9,306 U/L, reference values 20-170 U/L). Blood pressure was 153/80 mmHg. EKG showed U waves . A computed tomography (CT) lumbar spine scan was done in the ED to evaluate the bilateral lower extremity weakness, which revealed a 3.3 cm low-density cystic mass arising from the left adrenal gland versus the superior pole of the left kidney . She received 3 L of normal saline (NS) in the ED and KCl three times. Her potassium level dropped to 1.9 mmol/L, and she received IV KCl twice and 80 mEq orally; however, her potassium further dropped to 1.7 mmol/L, and she was admitted to the stepdown unit (SDU). Section title: Case presentation Educational score: 3.721911668777466 Domain: clinical Document type: Clinical case Language: en In the SDU, endocrinology was consulted, and the patient was started on D5-half NS with 40 mEq KCl and 100 mg spironolactone. Serum potassium remained low despite aggressive repletion, and CK levels continued to rise despite aggressive hydration and no further massage gun usage. CK levels rose to a maximum of 22,000 U/L and began to downtrend when potassium started to normalize in a sustained manner (Table 1 and Table 2 ). Her erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were minimally elevated, ruling out inflammatory myopathy. The patient was discharged once stable and had a follow-up with an endocrinologist and endocrine surgeon. Section title: Case presentation Educational score: 3.955965757369995 Domain: clinical Document type: Clinical case Language: en A month later, she had a dedicated CT abdomen with contrast, which showed a 3.2 cm left adrenal nodule with precontrast, dynamic, and delayed phase imaging as 16, 81, and 36 Hounsfield units, respectively. The relative percent washout value was greater than 40% and was compatible with adenoma . The right adrenal gland was unremarkable. Her latest potassium level was 4.8 mmol/L with potassium supplementation and spironolactone. Laparoscopic adrenalectomy was then performed, after which her potassium and aldosterone levels returned to normal. Histopathology report further supported the diagnosis of an adrenal adenoma due to positive melanin A and calretinin, focal weak positive synaptophysin, and negative chromogranin and paired-box gene 8 (PAX8). After her discharge, she had no recurrence of her symptoms. Section title: Discussion Educational score: 4.288939476013184 Domain: biomedical Document type: Clinical case Language: en Rhabdomyolysis is a pathological condition in which skeletal muscle breakdown leads to the release of muscle-breakdown products such as CK, myoglobin, lactic acid, and lactate dehydrogenase (LDH) into the bloodstream . The causes of rhabdomyolysis are typically categorized as physical and non-physical. Physical causes include crush syndrome in approximately 37% of cases, intense physical activity, e.g., strength training, which makes up about 38% of cases related to physical activity, and muscle exertion due to seizures . Non-physical causes include multiple factors such as chronic alcoholism, drugs like cocaine and amphetamines, medications like statins, infections, inflammatory myopathies, heat stroke, neuroleptic malignant syndrome (NMS), and genetic disorders of glycogen storage like McArdle's disease . During pregnancy, women are at risk of hypokalemia-induced rhabdomyolysis due to causes such as hyperemesis-induced hypokalemia and underlying distal renal tubular acidosis, which can be unmasked in pregnancy . There has also been a reported case of rhabdomyolysis following intravenous iron sucrose administration during pregnancy . Meanwhile, in non-pregnant adults, iron-dextran and ferric gluconate supplements have led to rhabdomyolysis . In this case, the patient had no history of anemia or iron supplementation during or after her pregnancy. She reported using a percussion massage gun to alleviate cramps and muscle weakness, the use of which has been attributed as a cause of rhabdomyolysis . However, the discovery of an adrenal adenoma and the subsequent resolution of her symptoms suggest that the adrenal pathology was most likely the causative factor. Section title: Discussion Educational score: 4.203293323516846 Domain: biomedical Document type: Clinical case Language: en Rhabdomyolysis, the breakdown of muscle tissue, releases potassium into the bloodstream, leading to hyperkalemia; it also releases toxic substances like myoglobin, which can result in multi-organ failure, with AKI being the most serious complication. Increased levels of myoglobin can cause up to 40% of patients with rhabdomyolysis to develop acute renal failure . A commonly used clinical definition for rhabdomyolysis is CK levels almost five times the normal limit, and typically, CK levels >5,000 are correlated with severe muscle injury and AKI . This patient was diagnosed as having rhabdomyolysis due to extremely high CK levels (9,306 U/L) on presentation, which further rose to a maximum of 22,000 U/L. Section title: Discussion Educational score: 4.181026935577393 Domain: biomedical Document type: Other Language: en Rhabdomyolysis associated with hypokalemia is a rare presentation, as hyperkalemia is generally the expected outcome of muscle breakdown. Typically, rhabdomyolysis occurs when potassium levels fall below 2.0 mmol/L . Hypokalemia can be due to several causes; these include medications such as diuretics and laxatives, diarrhea, renal diseases like types I and II renal tubular acidosis, inadequate nutrition, and insulin overdose . Low potassium levels lead to ECG findings like T-wave and ST segment depression, QT-prolongation, and the appearance of a U-wave - potentially causing fatal cardiac arrhythmias . Other complications may include intestinal and respiratory paralysis . Hypokalemia usually presents as progressive muscle weakness, more commonly in the lower limbs, as seen in this patient, along with other symptoms such as fatigue, constipation, and palpitations . Section title: Discussion Educational score: 4.405492782592773 Domain: biomedical Document type: Clinical case Language: en Another cause of hypokalemia is hormonal imbalance, particularly that of aldosterone. This can result from primary hyperaldosteronism, also known as Conn Syndrome, which may be caused by either an adrenal adenoma (30%) or BAH (60%) . Secondary hyperaldosteronism is usually due to hyperactivity of the renin-angiotensin-aldosterone system (RAAS), usually due to a renin-producing tumor. Excessive aldosterone causes sodium retention and potassium excretion due to the activation of mineralocorticoid receptors on renal cells, which then leads to sodium reabsorption via the epithelial sodium channels (ENaC) on the luminal side of the cortical collecting duct and potassium excretion via the sodium-potassium exchange pumps. Sodium reabsorption leads to water retention, which, alongside aldosterone's direct action of vasoconstriction, causes hypertension . In the majority of cases, potassium levels are within the normal range. Because hypokalemia is observed in only about 28.1% of patients with hyperaldosteronism, this case report highlights how unusual it is for hypokalemia to be severe enough to result in rhabdomyolysis . Section title: Discussion Educational score: 4.114539623260498 Domain: biomedical Document type: Other Language: en One proposed explanation for the connection between hypokalemia and rhabdomyolysis is that potassium plays a role in dilating arterioles in skeletal muscles, particularly during physical activity. This dilation is impaired when serum potassium levels are low, resulting in reduced blood flow and relative ischemia in the muscle fibers . Another theory suggests that hypokalemia inhibits the production and storage of glycogen within cells and disrupts normal ion movement across cell membranes . Given the vital role potassium plays in maintaining normal physiological functions like muscle contraction and normal heart rhythm, inpatient management of such patients is crucial to replete total body potassium stores and correct serum potassium levels to prevent them from developing critical illnesses such as muti-organ failure and AKI. Section title: Conclusions Educational score: 3.9945614337921143 Domain: biomedical Document type: Other Language: en Primary hyperaldosteronism leading to hypokalemia is a rare but important cause of rhabdomyolysis and should be considered as a differential when patients present with muscle weakness and lab findings consistent with rhabdomyolysis. Therefore, physicians must maintain a high degree of clinical suspicion for this diagnosis, especially in the setting of muscle weakness, elevated CK levels, and low serum potassium. Recognizing the potential link between hypokalemia and rhabdomyolysis is essential for guiding further investigation and ensuring appropriate management of affected patients. Early recognition and intervention can prevent serious complications, ultimately improving patient outcomes. | Clinical case | biomedical | en | 0.999997 |
PMC11698544 | Section title: Introduction Educational score: 4.273148059844971 Domain: biomedical Document type: Clinical case Language: en Craniosynostosis is a congenital condition in which one or more of the sutures in the skull fuse prematurely, restricting skull growth and leading to an abnormal head shape. These sutures are normally flexible joints that allow the skull to expand as the brain grows; however, when they fuse too early, the skull cannot grow in the affected areas, resulting in compensatory growth in other regions. Oxycephaly is a rare form of craniosynostosis that causes the skull to have a cone or tower-shaped appearance. It occurs due to the premature fusion of the coronal and sagittal sutures, which prevents the skull from growing normally in width . This condition is typically identified shortly after birth and is often treated with surgical intervention aimed at reducing pressure on the brain and correcting the abnormal skull shape. The management of craniosynostosis has seen significant advancements in recent years, with innovations in both surgical techniques and supportive care. Traditional open cranial vault remodeling, once the primary approach, has been refined to improve outcomes and reduce recovery time. If left untreated, oxycephaly can lead to developmental delays and blindness . We present this case to highlight key aspects of late-presenting multi-suture craniosynostosis and its management. Section title: Case presentation Educational score: 3.4841506481170654 Domain: clinical Document type: Clinical case Language: en A five-year-old girl, born preterm at 35 weeks via lower-segment cesarean section (LSCS) from a non-consanguineous marriage, had a birth weight of 1.7 kg. She presented with a history of frequently rubbing her right eye. Although her mother did not observe any signs of visual impairment, she had noted an abnormal head shape since birth. The child had no significant systemic history, and her developmental milestones were achieved on time without any delays. General examination revealed alert child with GCS 15. Physical examination revealed a high, peaked forehead and a shortened, pointed head shape indicative of oxycephaly . Section title: Case presentation Educational score: 4.018237113952637 Domain: biomedical Document type: Clinical case Language: en Notable craniofacial features included maxillary recession, a trapezoid-shaped skull with right facial scoliosis, bony nasal septal deviation to the left, and right brow asymmetry. The recorded anthropometric measurements included a head circumference of 44 cm (normal range: 49-51 cm), a weight of 26 kg (normal range: 15-23 kg), a height of 136 cm (normal range: 105-115 cm), and a calculated body mass index (BMI) of 14.1 kg/m² (normal range: 14-17 kg/m²). The ocular assessment revealed a best corrected visual acuity (BCVA) of 1/60 in the right eye and 6/6 in the left eye, with bilateral proptosis. The right eye exhibited defective color vision and generalized field depression. Fundus examination revealed a pale disc with peripapillary infarction in both eyes . Section title: Case presentation Educational score: 4.218173980712891 Domain: biomedical Document type: Study Language: en CT brain imaging with 3D reconstruction confirmed pan-sutural craniosynostosis, showing a flattened forehead, prominent pre-coronal hump, and inner calvarial table scalloping, all indicative of raised intracranial pressure (ICP). Contrast-enhanced MRI (CEMRI) with MRV and MRA revealed normal brain architecture but severe optic nerve sheath edema. MRV demonstrated partial transverse sinus hypoplasia with collateral circulation & venous shunts, suggesting long-standing raised ICP . Section title: Case presentation Educational score: 2.7944693565368652 Domain: clinical Document type: Clinical case Language: en Genetic testing was performed and returned negative. The diagnosis was compressive optic neuropathy due to non-syndromic craniosynostosis (oxycephaly). Treatment involved bilateral frontal-orbital advancement and posterior vault remodeling to relieve optic nerve compression . Section title: Case presentation Educational score: 3.803098440170288 Domain: clinical Document type: Clinical case Language: en Exposure keratitis was identified as an early postoperative complication, with signs observed on the first postoperative day, including mild conjunctival hyperemia, punctate epithelial erosions, and mild lagophthalmos. Management included the use of lubricating eye drops and ointment, along with a temporary tarsorrhaphy, which was removed after one month. These interventions effectively addressed the ocular surface concerns during the early postoperative period. The follow-up schedule for the study included weekly evaluations for the first month, followed by monthly visits for three months, and subsequently monitored every six months till date. Post-surgery, the patient's vision improved to 6/24 in her right eye at the end of one year follow-up . Section title: Discussion Educational score: 4.210488319396973 Domain: biomedical Document type: Review Language: en Craniosynostosis is a relatively rare condition that affects approximately 1 in 1000 infants . Craniosynostosis is a developmental disorder characterized by the premature fusion of cranial sutures, which restricts normal skull and brain growth. Typically, the sutures in an infant’s skull remain open to allow the skull to expand as the brain grows. However, early fusion results in restricted growth perpendicular to the fused sutures (Virchow's law), causing cranial deformities, increased intracranial pressure, and potential neurological deficits . This condition is due to abnormal development of the primitive mesoderm. Recent studies have highlighted a concerning rise in the occurrence of craniosynostoses, a medical condition where the skull sutures fuse prematurely. The increase in craniosynostosis cases is thought to result from both genetic and environmental factors . Environmental risks include fetal head constraint, abnormal fetal position, low amniotic fluid, exposure to teratogens, maternal smoking, and specific medications during pregnancy . Section title: Discussion Educational score: 4.275912761688232 Domain: biomedical Document type: Clinical case Language: en About 20% of craniosynostosis cases have a genetic basis, often due to autosomal dominant FGFR (Fibroblast growth factor receptor) mutations-FGFR1 in Pfeiffer's syndrome and FGFR2 in Apert’s and Crouzon’s syndromes . Non-inherited mutations, as observed in our case, account for approximately 50% of cases. Craniosynostosis primarily affects the sagittal suture (60%), followed by the coronal (25%), metopic (15%), and lambdoid sutures (2%) . In our case, the patient presented with premature pansutural craniosynostosis, leading to a tower-shaped skull due to restricted transverse brain growth. The absence of developmental delay, focal neurological deficits, or feeding problems made this condition challenging to detect during infancy. Furthermore, measuring head circumference during routine pediatric vaccination visits can aid in the early detection of craniosynostosis. Regular vision screenings conducted by school teachers play a crucial role in identifying any problems at an early stage and preventing complications like amblyopia. Interdisciplinary team care is important for diagnosis and treatment. Ophthalmic manifestations of craniosynostosis include optic atrophy, exophthalmos, exotropia, nystagmus, and mental deficiency . Optic atrophy is one of the most concerning ocular consequences of craniosynostosis. It occurs due to increased intracranial pressure, mechanical traction, compression, and narrowing of the optic foramen . The occurrence of asymmetric vision loss may stem from disparate sizes of optic canals, as depicted in our case. The primary goals of treatment are to ensure normal brain development and achieve a cosmetically acceptable appearance. Section title: Discussion Educational score: 4.15875244140625 Domain: biomedical Document type: Review Language: en The optimal time for surgery is debated, but it is generally considered between six and twelve months of age . The type and extent of surgery depend on the patient's age and presentation. The options for surgical intervention include open craniotomy and reconstruction or an endoscopic procedure. Endoscopic intervention is more suitable until the age of 6 months when cranial bones are still flexible. After surgery, additional corrections with helmets may be needed for four to six months. After six months, open surgery is preferred due to bone stiffness as done in our case. In particular, frontal advancement open surgery is an effective surgical method for expanding the cranial vault, regardless of age . This procedure involves removing the fused sutures and reshaping the forehead, which can significantly reduce the pressure on the optic nerve. Ideally, surgery should be performed in the first year of life . In craniosynostosis surgery, specifically frontal orbital advancement combined with posterior vault remodeling, several factors regarding its benefits and potential complications must be considered. This combined approach addresses both anterior and posterior cranial vaults, facilitating balanced expansion to accommodate normal brain growth while significantly improving craniofacial aesthetics by correcting deformities and enhancing facial symmetry. Additionally, it reduces the risk of elevated intracranial pressure, thereby preventing neurodevelopmental complications. Despite the improved safety of craniosynostosis surgery, complications remain a concern . Section title: Discussion Educational score: 4.068406105041504 Domain: biomedical Document type: Study Language: en A study conducted by Esparza et al. analyzed the complications associated with the surgical treatment of craniosynostosis and craniofacial syndromes involving 306 transcranial procedures . The most frequent complication was postoperative hyperthermia, occurring in 13.17% of cases, followed by infections (8.10%), subcutaneous hematomas (6.08%), dural tears (5.06%), and cerebrospinal fluid leakage (2.7%). Notably, endoscopic-assisted osteotomies reported the lowest complication rate at 2.5%, while complete cranial vault remodeling had the highest rates of complications. Section title: Discussion Educational score: 4.170571327209473 Domain: biomedical Document type: Study Language: en Despite these complications, all cases were resolved without permanent deficits, highlighting the effectiveness of surgical interventions . Endoscopic correction offers certain advantages over open cranial vault reconstruction, including shorter surgery times, reduced blood loss, and quicker recovery periods, with fewer ICU and hospital stays. However, endoscopic techniques often require postoperative use of helmet-molding orthoses for several months to guide proper bone alignment and prevent suture refusion as the brain continues to grow. Both surgical approaches require long-term follow-up to monitor for late complications such as irregular bone contour, incomplete bone healing, or refusion of the sutures, which may necessitate reoperation. These considerations highlight the importance of tailored surgical planning and diligent postoperative care to optimize outcomes and minimize risks. However, even if the diagnosis is made at a later stage, the prognosis can be improved through intervention as seen in our case. The study by Gutierrez-Pineda F et al. demonstrated a 1% reoperation rate, a 95% success rate for achieving excellent aesthetic outcomes, and an 86% requirement for transfusions during procedures. Furthermore, the pooled complication rate was 2%, underscoring the minimal morbidity and highlighting the overall safety and efficacy of these surgical techniques . Fortunately, our patient experienced no serious complications post-surgery. Regular follow-ups are essential to monitor head growth, detect increased ICP, and identify any potential issues. Section title: Conclusions Educational score: 1.8662869930267334 Domain: biomedical Document type: Other Language: en Oxycephaly poses a serious health concern that has the potential to affect both vision and neurological impairment. It is crucial for medical professionals to meticulously screen children for this condition. However, with the aid of surgical procedures, the prognosis for children with oxycephaly has significantly improved. | Clinical case | biomedical | en | 0.999997 |
PMC11698545 | Section title: Introduction Educational score: 4.24106502532959 Domain: biomedical Document type: Review Language: en Nephrogenic bladder adenoma is a rare benign metaplastic lesion of the urothelium, also called nephrogenic adenoma, mesonephroid metaplasia, or adenomatous metaplasia . Although it is most often observed in the urinary bladder (68.6%), it can also affect other parts of the urinary tract, such as the urethra (13.3%), ureter (8.2%), renal pelvis (8.2%), and in rare cases, the prostate (2%) . Research shows that environmental factors and specific lifestyle behaviors, such as cigarette smoking, can contribute to its development . This condition is often associated with previous inflammatory processes in the bladder, such as recurrent infections, inflammation caused by bladder stones, foreign bodies, intravesical therapy, chemical exposure, radiotherapy, or previous bladder surgery . Nephrogenic adenoma is of particular importance due to the differential diagnosis, which can favor clear cell adenocarcinoma, endocervicosis, papillary urothelial carcinoma, prostatic adenocarcinoma of the bladder, and nested variant of urothelial carcinoma. Section title: Introduction Educational score: 3.8134524822235107 Domain: biomedical Document type: Other Language: en Nephrogenic adenoma manifests clinically with nonspecific symptoms of the urinary tract, with irritative symptoms such as urgency and frequent urination being the most common. Hematuria is uncommon . An altered mucosal appearance, which is typically characterized by vesicles and bullae, is typically revealed by cystoscopic examination. This appearance can be closely resembling that of papillary carcinoma of the urinary bladder . Section title: Introduction Educational score: 4.118232727050781 Domain: biomedical Document type: Study Language: en Histologically, nephrogenic adenoma is defined by tubular and papillary formations lined by low cuboidal to columnar epithelial cells. Its immunohistochemical profile can vary but is often marked by positivity for paired box (PAX) 2, PAX8, and cytokeratin 7 (CK7), along with negativity for p63 and prostate-specific antigen (PSA) . Section title: Case presentation Educational score: 3.543649435043335 Domain: clinical Document type: Clinical case Language: en An 84-year-old female patient presented for examination with a history of hematuria and stated that she had been passing sandlike granules in her urine for the past few months. It also provides anamnestic data on recurrent urinary infections. Urinalysis revealed a significant number of leukocytes and 5-10 erythrocytes per high-power field. Echosonographic examination of the urinary tract revealed bilateral microcalculosis up to 6 mm as well as hyperechoic thickening with a diameter of about 10 mm on the right side wall of the urinary bladder . Section title: Case presentation Educational score: 4.123378753662109 Domain: biomedical Document type: Clinical case Language: en Rigid cystoscopy, performed based on prior sonographic findings, showed bullous and hyperemic changes on the right lateral wall, partially covered by fibrin deposits, which were suggestive of a tumorlike lesion . Transurethral resection of the lesion was subsequently performed, along with electrocauterization of the surrounding mucosa. Histopathological examination, including hematoxylin and eosin (H&E) and immunohistochemical staining (AE1/AE3, CK7, CK20, CD34, p63), confirmed the diagnosis of nephrogenic adenoma vesicae urinariae, characterized by chronic inflammatory infiltrates and metaplastic mucosa forming papillary, cystic, and tubular structures lined by a single layer of cuboidal cells with minimal atypia . Section title: Case presentation Educational score: 3.6621744632720947 Domain: clinical Document type: Clinical case Language: en At the first follow-up, one month after surgery, the patient reported no symptoms. Urinalysis, which included checking the appearance of color, clarity/turbidity, pH, specific gravity, glucose, ketones, nitrites, leukocyte esterase, bilirubin, urobilinogen, blood, protein, erythrocytes, leukocytes, squamous epithelial cells, crystals, and bacteria, was normal. Microbiological analysis, urine culture, was also performed, which was free of bacterial growth, while urine cytology did not show the presence of abnormal cells. Follow-up with rigid cystoscopy was planned every three months, followed by periodic urinalysis and culture. Although significant bacteriuria was occasionally detected, the patient remained asymptomatic and was treated with non-antibiotic preparations. Section title: Case presentation Educational score: 3.628666877746582 Domain: clinical Document type: Clinical case Language: en Nine months after the first surgery, cystoscopy revealed hyperemic bullous-cystic changes on the posterior wall and roof of the bladder as well as near the scar from the previous surgery. These lesions measured up to 10 mm and bled easily when manipulated. A second transurethral resection was performed, and histopathological findings were consistent with the previous diagnosis of nephrogenic adenoma vesicae urinariae. Section title: Case presentation Educational score: 1.4471219778060913 Domain: clinical Document type: Clinical case Language: en The patient has been regularly monitored for 48 months after the second surgery, with rigid cystoscopy performed every six months. No new tumor changes have been observed during this period. Her follow-up regimen also includes urine analysis and culture every three months, as well as periodic sonographic examination of the urinary tract. Section title: Discussion Educational score: 2.816018581390381 Domain: biomedical Document type: Other Language: en Nephrogenic adenoma of the urinary bladder was first described by Davis in 1949 as a bladder hamartoma . Although it is considered a benign metaplastic lesion due to the possibility of recurrence and the rare possibility of malignant transformation, long-term follow-up is crucial. Section title: Discussion Educational score: 4.0411176681518555 Domain: clinical Document type: Clinical case Language: en This case highlights the importance of accurate histopathological diagnosis and careful follow-up of patients with nephrogenic adenoma due to the lack of standardized treatment protocols. An accurate diagnosis reduces potential diagnostic confusion, as changes that mimic other lesions such as urothelial carcinoma or chronic inflammation can be seen. It reduces the need for additional diagnostic procedures such as imaging and invasive biopsy. It reassures patients and allows them to focus on an appropriate treatment plan, thereby ensuring the preservation of urinary tract function. Misdiagnosis can lead to delays in appropriate treatment and can cause significant psychological distress, leading to anxiety and uncertainty about the prognosis. However, overtreatment of a benign lesion could result in unnecessary surgical risks, prolonged recovery time, and potential complications. Section title: Discussion Educational score: 2.5818092823028564 Domain: biomedical Document type: Clinical case Language: en The patient who has been monitored for the last five years shows a recurrence of the disease but without pathohistological findings that would show signs of malignant transformation. This raises the question of whether such transformation occurs at the site of the initial lesion, the nephrogenic adenoma, or whether a new neoplastic formation of the bladder could develop elsewhere. Section title: Discussion Educational score: 4.248968124389648 Domain: biomedical Document type: Review Language: en Vemulakonda et al. reported a case of recurrent nephrogenic adenoma of the bladder in a 10-year-old boy with a history of plum syndrome. They stated in their opinion that their reported case was the first reported case of recurrent nephrogenic adenoma in a patient with a history of plum belly syndrome. While most cases of nephrogenic bladder adenoma have a benign and unrepeatable biological behavior, the conclusion drawn from this report indicates that regular follow-up cystoscopies would be necessary in order not to miss a recurrent nephrogenic bladder adenoma. Boscolo-Berto et al. described a case in which a patient experienced three relapses within the same diverticulum, with an identical pathohistological finding of a nephrogenic adenoma that was treated with transurethral resections. Since they considered the nephrogenic adenoma to be a benign lesion without any direct evidence of possible evolution into malignancy, they conducted several years of cystoscopic follow-up. Their work is also one of the first reports of a nephrogenic adenoma showing recurrence, but the first case of a highly recurrent nephrogenic adenoma in the same diverticulum that was treated conservatively with routine transurethral resection. Hartmann et al. documented the case of a 70-year-old woman who experienced multiple recurrences of nephrogenic metaplasia in the bladder, which eventually led to the development of clear cell adenocarcinoma. The results of the molecular studies they conducted suggested the clonal evolution of nephrogenic metaplasia to the appearance of cellular adenocarcinoma in this case. Hungerhuber et al. reported a 25-year-old man who had trauma to the urinary bladder caused by a traffic accident. After the patient recovered from the accident, he developed a nephrogenic adenoma and recurrent urinary tract infections. Since the accident, he had a nephrogenic bladder adenoma for 18 months. The adenoma was treated several times with transurethral resections. Initial pathological findings were benign; however, the last resection revealed that the previously benign adenoma had transformed into a moderately differentiated bladder adenocarcinoma. Dhaliwal et al. present a rare case of clear cell adenocarcinoma arising in the area of nephrogenic metaplasia. This is an unusual case because the morphology of nephrogenic metaplasia has been seen to change over time with the subsequent development of clear cell adenocarcinoma. Section title: Conclusions Educational score: 3.974719762802124 Domain: biomedical Document type: Review Language: en Nephrogenic adenoma, though benign, presents notable clinical challenges due to its rare but documented risk of malignant transformation and potential for recurrence. Its unpredictable nature combined with the lack of standardized treatment protocols underscores the need for careful, long-term monitoring. While transurethral resection remains the main treatment option, it is not always definitive, as recurrence can still occur even after complete resection. To improve management strategies that address both its benign and possible malignant aspects, further research is needed to better understand the underlying pathogenesis of nephrogenic adenoma. | Review | biomedical | en | 0.999996 |
PMC11698547 | Section title: Introduction Educational score: 4.143304347991943 Domain: biomedical Document type: Review Language: en Carotid body tumors (CBTs), also known as paragangliomas or chemodectomas, are uncommon neuroendocrine neoplasms that develop in glomus cells generated from the embryonic neural crest close to the carotid bifurcation. CBTs are reported to occur in 1-2 individuals per 100,000 people . Most of these tumors are asymptomatic and are typically discovered incidentally during radiological imaging or clinical examination. However, in symptomatic cases, discomfort, dysphagia, and autonomic dysfunction are the most commonly reported symptoms. The diagnosis of paragangliomas is primarily based on imaging, with computed tomography angiography (CTA) being the examination of choice. If a paraganglioma is suspected, a biopsy is contraindicated due to the high risk of hemorrhage . The preferred treatment is surgical excision, although embolization may also be performed to reduce tumor size and minimize bleeding during surgery . In cases where surgery is not feasible or necessary, radiotherapy may be considered . Through this article, we aim to contribute to the collective understanding and knowledge surrounding the incidental discovery and diagnosis of this rare, slow-growing CBT. Section title: Introduction Educational score: 0.921967089176178 Domain: other Document type: Other Language: en This article was previously posted as a preprint on the Research Square preprint server on 17 May 2024 . Section title: Case presentation Educational score: 3.7932779788970947 Domain: clinical Document type: Clinical case Language: en A 75-year-old woman with a 34-year history of diabetes and hypertension presented to the emergency room (ER) after experiencing multiple episodes of nausea and vomiting over the past 24 hours. She also reported a severe headache but denied any chest pain, abdominal pain, diarrhea, or dysuria. Upon admission, her blood pressure was 196/134 mmHg, and her heart rate was 140 beats per minute (bpm). The electrocardiogram (EKG) revealed atrial fibrillation (AF) with a rapid ventricular rate. She denied any prior history of AF and reported being compliant with all her medications with regular follow-ups with her primary care physician. She also reported no history of fever, cough, weight loss, anorexia, night sweats, diaphoresis, palpitations, dizziness, lightheadedness, or syncopal episodes. Physical examination showed elevated jugular venous pressure (JVP) with normal cardiac auscultation, and the rest of the systemic examinations were unremarkable. Section title: Case presentation Educational score: 0.9857860803604126 Domain: biomedical Document type: Other Language: en Investigations Section title: Case presentation Educational score: 3.930461883544922 Domain: clinical Document type: Clinical case Language: en Initial blood tests, including a complete blood count, renal function tests, liver function tests, and thyroid function tests (Table 1 ) were all within the normal limits. Additionally, a urine toxicology screen was negative for cannabinoids, amphetamines, or cocaine. The chest X-ray revealed no acute abnormalities. Similarly, the contrast-enhanced CT scan of the thorax and abdomen was normal. The CT scan of the head with contrast also indicated no acute abnormalities, except for an unclear submandibular mass. Further evaluation with a contrast-enhanced CT scan of the neck and an MRI of the neck with and without contrast revealed a stable mass measuring 38 x 53 x 15 mm on the left side, consistent with a carotid body paraganglioma (CBP) . This mass had remained stable in size compared to the previous examination seven years ago. Given the patient's newly diagnosed AF and hypertension, concern arose about a functionally active tumor. The hormonal evaluation showed elevated levels of spot plasma and urine metanephrines, while an abdominal CT scan showed no adrenal tumors. Section title: Case presentation Educational score: 1.0102065801620483 Domain: biomedical Document type: Other Language: en Treatment Section title: Case presentation Educational score: 3.2980215549468994 Domain: clinical Document type: Clinical case Language: en Her home medications of lisinopril 40 mg and amlodipine 10 mg were resumed. Despite being on two antihypertensives, her blood pressure remained at 180/94 mmHg, with a heart rate of 140 bpm. She was initially treated with intravenous (IV) metoprolol, and once her blood pressure and heart rate stabilized, she was switched to oral metoprolol. A conservative dosage of 12.5 mg metoprolol was given twice daily, with gradual increases based on her tolerance. Nausea was managed appropriately, and her electrolytes were optimized, allowing for diet advancements as tolerated. Given her age and associated comorbidities, radiotherapy was planned; however, the patient declined the treatment. Section title: Case presentation Educational score: 1.4808173179626465 Domain: biomedical Document type: Other Language: pt Outcome Section title: Case presentation Educational score: 1.8662093877792358 Domain: clinical Document type: Clinical case Language: en Once her vital signs stabilized and her nausea and vomiting subsided, there was significant improvement in her overall clinical condition. Metoprolol effectively controlled her heart rate and blood pressure, allowing for her discharge. Section title: Discussion Educational score: 4.417598724365234 Domain: biomedical Document type: Study Language: en A paraganglioma is a type of tumor that arises from paraganglia, which are clusters of neuroendocrine cells derived from neural crest cells. These tumors commonly arise in areas with abundant paraganglia, such as the carotid body, the vagus nerve in the head and neck, the jugular foramen, the middle ear, the aortopulmonary window, and the organ of Zuckerkandl . Among these, the carotid body is the most significant as it contains the largest concentration of paraganglia in the head and neck. This structure functions as a chemoreceptor, primarily monitoring oxygen levels in the blood. The carotid body helps regulate vital autonomic functions by initiating a sympathetic nervous system response to detect arterial hypoxemia. Typically, the carotid body measures around 3-5 mm, though it can grow over 8 cm in response to persistent hypoxic conditions . As a chemoreceptor, the carotid body responds to acidosis, hypoxia, and hypercapnia, playing a vital role in regulating blood pressure, heart rate, respiration, and blood temperature through increased sympathetic nervous system activity . Section title: Discussion Educational score: 4.135798454284668 Domain: biomedical Document type: Study Language: en CBTs account for approximately 65% of all paragangliomas in the head and neck . These tumors can manifest at any age, though they are most commonly seen in individuals aged 50-70 years, with a range from 18 to 94 years. Women are slightly more affected than men, with a male-to-female ratio of 1:1.9 . CBTs are typically sporadic, with around 25% having a hereditary basis due to mutations in succinate dehydrogenase genes, including SDHD, SDHB, and SDHC . Genetic mutations are the only identified risk factor for the development of CBTs, aside from hypoxic stimulation, and familial cases often present with bilateral CBTs at a higher frequency . Section title: Discussion Educational score: 4.446539878845215 Domain: biomedical Document type: Review Language: en CBTs and paragangliomas in the head and neck are typically painless, slow-growing tumors that often remain undetected for years before patients seek medical attention. The tumors can grow to significant sizes and may exhibit infiltrative growth, with local recurrence posing a risk of fatality. Five percent of paragangliomas secrete catecholamines (dopamine, epinephrine, and norepinephrine), with hypertension being the most common manifestation. This hypertension can be continuous, intermittent, or paroxysmal . The classic triad of headache, sweating, and palpitations occurs in 40% of cases . Dopamine-producing paragangliomas, which are rare, can present with normal blood pressure or even hypotension. Limited case reports suggest that CBTs, like pheochromocytoma, may present with AF. In cases of elevated catecholamine levels, additional imaging is recommended to exclude intra-abdominal tumors. Malignancy rates range from 10% to 50%. Histologic features indicating malignancy include necrosis, extensive capsular or vascular invasion, increased mitotic activity, atypical mitotic figures, loss of a well-differentiated zellballen pattern, reduction in the S-100 positive sustentacular cell population, and tumor cell spindling . Section title: Discussion Educational score: 4.147839546203613 Domain: biomedical Document type: Review Language: en CBTs are most commonly discovered incidentally during imaging studies or through clinical assessments. The most effective screening method for CBTs is a color-flow carotid duplex, where CBTs are identified by a well-defined hypoechoic mass causing the splaying of the internal carotid artery (ICA) and external carotid artery (ECA). Color Doppler imaging reveals hypervascularity within the lesion with a low-resistance flow pattern. Surgical removal depends on the tumor's relationship with the artery bifurcation and its proximity to cranial nerves, which can be accurately assessed through CTA or MR angiography (MRA). MRI is often more precise than CT due to its lack of ionizing radiation. Dynamic contrast-enhanced MRI and diffusion-weighted imaging (DWI) are particularly effective in distinguishing paragangliomas from other benign neoplastic tumors . Section title: Discussion Educational score: 3.78527569770813 Domain: biomedical Document type: Other Language: en Radical surgical resection is performed to prevent malignant transformation . The preoperative adrenergic blockade is recommended, while preoperative embolization remains controversial due to potential risks . Although embolization may be considered for large tumors, it increases the risk of transient ischemic attacks and ischemic strokes . Radiotherapy, recommended for patients with various medical conditions at risk during general anesthesia, has been shown to reduce tumor size or halt its growth. Section title: Discussion Educational score: 4.017676830291748 Domain: clinical Document type: Clinical case Language: en This case involves a 75-year-old woman with carotid body paraganglioma (CBP), complicated by new-onset AF and severe hypertension. While Hoang et al. focused on the presentation and surgical management of CBTs, this case offers novel insights into the association between paragangliomas and cardiovascular complications like AF, which are rarely documented . This case discusses the successful management of AF and severe hypertension using IV and oral metoprolol, illustrating the importance of careful cardiovascular management in patients with functionally active paragangliomas. This approach, particularly in an older patient with multiple comorbidities, adds value to the literature by focusing on the nonsurgical management of cardiovascular symptoms in CBT patients. Section title: Discussion Educational score: 4.095604419708252 Domain: biomedical Document type: Clinical case Language: en Compared to the case review by Hoang et al. , which focused on more typical symptoms of CBTs (e.g., neck mass, dysphagia, and hoarseness), this case demonstrates an atypical presentation without overt neck swelling, hoarseness, or swallowing issues. This challenges the assumption that CBTs present predominantly with local symptoms, expanding the understanding of the disease’s clinical spectrum. This report contributes to the literature by documenting the occurrence of AF, which has not been commonly emphasized in previous case studies of paragangliomas, including the study by Hoang et al. . The link between paragangliomas and secondary cardiovascular complications, particularly in the absence of adrenal tumors, is an emerging area that this case explores, offering an update on potential complications that should be monitored. Section title: Discussion Educational score: 3.981079339981079 Domain: biomedical Document type: Study Language: en The detailed hormonal workup and the discovery of elevated plasma and urine metanephrines underscore the importance of assessing functional activity in suspected paragangliomas. This reinforces the need for comprehensive hormonal evaluation, an aspect that may not have been emphasized in earlier reports. This finding is particularly relevant for clinicians when considering differential diagnoses for patients with new-onset AF and uncontrolled hypertension. Section title: Conclusions Educational score: 3.9660940170288086 Domain: biomedical Document type: Clinical case Language: en This article shares our insights and experiences in managing CBTs, which are rare, slow-growing, hypervascular neuroendocrine tumors with the potential for malignant transformation. Diagnosis typically involves a thorough assessment, including patient history, physical examinations, and radiological studies. This report presents an older patient with CBP and new-onset AF, highlighting the need for further research into the cardiovascular manifestations of paragangliomas. | Review | biomedical | en | 0.999997 |
PMC11698549 | Section title: Introduction Educational score: 4.055700302124023 Domain: biomedical Document type: Other Language: en Clostridium difficile is a spore-forming, Gram-positive, anaerobic bacillus ubiquitously found in the intestinal tracts of humans and animals, as well as in various environmental settings. Transmission occurs via the fecal-oral route through the ingestion of spores . Healthcare environments often facilitate transmission through contaminated surfaces and the hands of healthcare workers . C. difficile infection (CDI) is a leading cause of antibiotic-associated diarrhea, predominantly acquired as a nosocomial infection . Section title: Introduction Educational score: 3.0090606212615967 Domain: biomedical Document type: Other Language: en Since the late 20th century, CDI rates have risen markedly, particularly among individuals with recent or ongoing hospitalizations, with prevalence rates ranging from 3% to 26% . In India, CDI has emerged as a significant cause of antibiotic-associated diarrhea, with reported prevalence rates of 5-20% in the western and central regions . Section title: Introduction Educational score: 3.9514400959014893 Domain: biomedical Document type: Other Language: en CDI is a toxin-mediated gastrointestinal disease caused by the exotoxins A and B, produced by C. difficile . The clinical spectrum ranges from mild, watery diarrhea and abdominal pain to severe conditions like life-threatening colitis . Potential complications include toxic megacolon and intestinal perforation . Risk factors for CDI include broad-spectrum antibiotic use, advanced age, prolonged hospitalization, and colonization by C. difficile . Section title: Introduction Educational score: 3.7930402755737305 Domain: biomedical Document type: Review Language: en CDI imposes a substantial burden on healthcare systems by prolonging hospital stays, increasing ICU admissions, and raising treatment costs. It also contributes significantly to morbidity and mortality, with all-cause mortality rates estimated between 13% and 30% . While some patients recover with prompt treatment, others face challenges such as recurrent infections . Effective prevention of CDI requires timely case detection and the implementation of comprehensive prevention strategies . Section title: Introduction Educational score: 4.003114700317383 Domain: biomedical Document type: Other Language: en Case detection involves identifying clinical symptoms, particularly diarrhea defined as three or more loose or unformed stools within 24 hours , alongside diagnostic methods like stool culture, enzyme immunoassays, or PCR to detect C. difficile toxins or their genes . Treatment typically involves antibiotics such as vancomycin, fidaxomicin, and metronidazole, although recurrence rates remain high, necessitating novel approaches like fecal microbiota transplantation for recurrent cases . Section title: Introduction Educational score: 3.680091619491577 Domain: biomedical Document type: Study Language: en CDI represents a significant global health challenge, with increasing rates of community-acquired infections. Its impact on healthcare systems, particularly through heightened mortality, underscores the importance of understanding its burden in both hospital and community settings. However, studies on CDI in the eastern region of India remain limited, despite its unique sociodemographic and healthcare dynamics. The 2021 ICMR national surveillance study reported that less than 5% of its data originated from eastern India, highlighting significant knowledge gaps regarding CDI's epidemiology and burden in this region . Section title: Introduction Educational score: 3.355970621109009 Domain: biomedical Document type: Other Language: en Determining the incidence of CDI and identifying the factors associated with infection among hospitalized patients can provide valuable insights for healthcare workers and stakeholders. These findings can guide the implementation of effective diagnostic methods, optimize therapeutic strategies, and strengthen infection control practices to mitigate the burden of CDI in healthcare settings. Section title: Introduction Educational score: 2.675671339035034 Domain: biomedical Document type: Study Language: en Keeping these considerations in mind, the study was conducted with the aim of determining the incidence of CDI among adult patients admitted to the inpatient department of a tertiary care hospital and identifying the risk factors associated with CDI. Section title: Materials and methods Educational score: 3.342587471008301 Domain: biomedical Document type: Study Language: en A prospective observational study was conducted over six months, from October 2022 to March 2023, after obtaining Institutional Ethics Committee approval . The study was carried out at the Kalinga Institute of Medical Sciences in Bhubaneswar, India. All consecutively admitted patients aged over 18 years, regardless of clinical condition or gender, and who consented to participate, were enrolled. A total of 200 patients were included in the study. Section title: Materials and methods Educational score: 3.9354538917541504 Domain: biomedical Document type: Study Language: en Patient demographic data, including age and sex, as well as medical history, were collected via a case record form. This included information on underlying diseases such as irritable bowel syndrome, inflammatory bowel disease, type 2 diabetes mellitus, and other immune-related disorders. Clinical variables, including provisional diagnoses at admission, broad-spectrum antibiotic usage during hospitalization (such as fluoroquinolones, third- and fourth-generation cephalosporins, and carbapenems), and hospital-related variables for gastrointestinal symptoms like diarrhea, dysentery, and abdominal pain occurring after 72 hours of hospitalization, were also recorded. The duration of hospital stay was noted as well. Section title: Materials and methods Educational score: 3.7120206356048584 Domain: biomedical Document type: Study Language: en Two stool samples were collected from each patient: the first within 24 hours of admission and the second on the day of discharge or after one week, whichever was longer. Patients were provided with wide-mouth sterile containers with lids for stool collection and were instructed not to take any laxatives the night before collection. Fresh stool samples of 10-15 grams, either formed or unformed, were placed in leakproof containers and transported to the laboratory in ice packs to maintain a temperature of 4-8°C, then stored in a refrigerator for further testing. Section title: Materials and methods Educational score: 3.8388168811798096 Domain: biomedical Document type: Study Language: en Stool samples were processed in the microbiology laboratory. A routine microscopic examination was performed to detect fecal leukocytes or pus cells. The samples were tested for C. difficile toxins A and B using the enzyme-linked immunosorbent assay (ELISA) method in a multi-step process to confirm CDI cases. Section title: Materials and methods Educational score: 1.7418032884597778 Domain: biomedical Document type: Other Language: en ELISA kit and procedure Section title: Materials and methods Educational score: 4.017660617828369 Domain: biomedical Document type: Study Language: en The Epitope Diagnostics ELISA kit for C. difficile Toxin A and B was used for toxin detection. The kit included all required reagents and instructions specific to toxin detection. The procedure was performed according to the manufacturer’s guidelines. At the end of the ELISA procedure, the absorbance (optical density, OD) of each microwell was measured using a Bio-Rad ELISA reader at 450 nm, with duplicate readings for each well. Section title: Materials and methods Educational score: 0.8369439840316772 Domain: biomedical Document type: Other Language: en Interpretation of results Section title: Materials and methods Educational score: 3.9634382724761963 Domain: biomedical Document type: Study Language: en The average OD value for each well was calculated. Results were interpreted according to the manufacturer's guidelines: a positive result was defined if the OD value exceeded the positive cutoff (0.168), negative if the OD was below the negative cutoff (0.138), and equivocal if the OD was between the two cutoffs (0.139-0.167). For equivocal results, the test was repeated with a different sample. Section title: Materials and methods Educational score: 3.7262890338897705 Domain: biomedical Document type: Study Language: en Clinical and laboratory data were entered into Microsoft Excel. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 26.0 . Descriptive statistics such as mean, standard deviation, and median were calculated for continuous variables. Proportions were determined for categorical variables. The Mann-Whitney U test was used to assess associations between continuous variables, while the chi-square or Fisher’s exact test was used for categorical variables. A p-value of less than 0.05 was considered statistically significant. Section title: Results Educational score: 3.9324862957000732 Domain: biomedical Document type: Study Language: en The present study enrolled a total of 200 patients admitted to the medicine wards of a tertiary care hospital. The incidence of CDI during the study period was found to be 9% (18/200). The median age of the participants was 45.5 years, with a range from 18 to 80 years. Male patients (60%) outnumbered female patients (40%). A total of 38 patients (19%) had a history of prior hospitalization, and 22% had underlying diseases. The median duration of hospitalization among participants was four days. Broad-spectrum antibiotic exposure during hospitalization was noted in 60% of patients. Section title: Results Educational score: 3.931959867477417 Domain: biomedical Document type: Study Language: en After 72 hours of hospitalization, 21% of the participants developed loose stools. At the time of admission (when the first stool samples were collected), none of the samples showed the presence of pus cells on routine microscopic examination or C. difficile toxin on the ELISA test. However, stool samples collected at discharge or after one week (second stool sample) tested positive for both stool pus cells and C. difficile toxins by ELISA in 9% of cases. Table 1 provides the sociodemographic and clinical parameters of the study participants. Section title: Results Educational score: 2.5001800060272217 Domain: biomedical Document type: Study Language: en Figure 1 shows that among the 200 admitted patients, acute febrile illness was the most common provisional diagnosis, accounting for 36% of cases, followed by urinary tract infection at 17%. Section title: Results Educational score: 4.048391342163086 Domain: biomedical Document type: Study Language: en Table 2 presents the sociodemographic and clinical profile of the C. difficile -infected cases. The mean age of the C. difficile toxin-positive patients was 50.77 ± 16.12 years, with a median age of 49 years. CDI was detected in 10% (12/120) of male patients and 7.5% (6/80) of female patients. Among participants with and without a history of prior hospitalization, CDI was found in 4/38 (10.5%) and 14/162 (8.6%), respectively. Fourteen of the 18 toxin-positive cases had no underlying comorbidities. There was no significant association between CDI-positive cases and prior hospitalization or underlying comorbidities. Section title: Results Educational score: 4.126332759857178 Domain: biomedical Document type: Study Language: en The median duration of hospital stay was significantly longer in ELISA-positive cases (eight days) compared to ELISA-negative cases (three days). All CDI cases (100%) were exposed to broad-spectrum antibiotics during hospitalization. After 72 hours of hospitalization, 42/200 patients developed loose stools, 28.6% of whom were C. difficile toxin ELISA positive. Stool pus cells were detected in all CDI-positive cases. The development of CDI was significantly associated (p < 0.001) with the mean duration of hospitalization, exposure to broad-spectrum antibiotics, the development of gastrointestinal symptoms, and the presence of stool pus cells. Section title: Results Educational score: 2.6779744625091553 Domain: biomedical Document type: Study Language: en Figure 2 shows that CDI cases were most commonly detected among patients with acute febrile illness, pneumonia, and enteric fever. Section title: Results Educational score: 4.022825241088867 Domain: biomedical Document type: Study Language: en In Figure 3 , the frequency of antibiotic use among C. difficile toxin ELISA positive and negative cases is presented. Among the 200 study participants, the majority (32%) were treated with a combination of various antibiotics, followed by third-generation cephalosporins. Of the 18 CDI cases, the majority (six cases) were treated exclusively with third-generation cephalosporins, followed by a combination of antibiotics (four cases). Section title: Discussion Educational score: 3.645765781402588 Domain: biomedical Document type: Study Language: en CDI is a significant healthcare concern, primarily due to its association with antibiotic use and nosocomial transmission. This study aimed to investigate the incidence of CDI among patients attending a tertiary care teaching hospital and explore the associated risk factors and clinical characteristics. Section title: Discussion Educational score: 4.073790550231934 Domain: biomedical Document type: Study Language: en Our findings revealed that the incidence of CDI among hospitalized patients during the study period was 9%, aligning with previous studies reporting incidence rates ranging from 3% to 29% . Notably, this rate was slightly higher than that reported by Ozaki et al. , but consistent with studies by Chaudhry et al., which reported a 6% incidence rate . Interestingly, studies from India have shown considerable variation in CDI prevalence, with some reporting rates as high as 25-30% among hospitalized patients with diarrhea. In contrast, Segar et al. reported a prevalence rate of 4% in their study . These differences can be attributed to variations in population characteristics, diagnostic methods, and hospital settings. Section title: Discussion Educational score: 3.833317995071411 Domain: biomedical Document type: Study Language: en The relatively low prevalence observed in our study could be due to several factors, including selective prescribing of probiotics to patients on prolonged and broad-spectrum antibiotic therapy, stringent surveillance with an improved antibiotic policy, and the active involvement of the hospital infection control team. Additionally, we did not include ICU-admitted patients in our study, who are typically exposed to higher antibiotic use and have longer hospital stays, increasing the likelihood of CDI occurrence. Section title: Discussion Educational score: 4.041341781616211 Domain: biomedical Document type: Study Language: en Although age was not found to be a significant factor for CDI development in this study, the mean age of the C. difficile toxin-ELISA positive cases was numerically higher (50.77 ± 16.12 years) than that of the negative cases. This finding is consistent with previous studies by Vishwanath et al. and Segar et al. , which reported a higher prevalence of CDI among older patients. Advanced age (≥60 years) is a recognized risk factor for CDI, likely due to increased healthcare exposure, antibiotic use, and the presence of underlying comorbidities. However, this observation was not statistically significant in our study and should be interpreted with caution. Section title: Discussion Educational score: 4.056060791015625 Domain: biomedical Document type: Study Language: en Regarding gender distribution, our study showed a higher proportion of C. difficile toxin-positive cases among males (60%), consistent with findings by Chaudhry et al. . This finding contrasts with reports by Vaishnavi et al., suggesting variability in CDI gender distribution across different studies . Gender differences in CDI incidence may result from biological factors such as differences in immune responses and sociocultural factors like variations in healthcare-seeking behavior or antibiotic exposure. Further studies are needed to understand the factors contributing to gender disparities in CDI prevalence. Section title: Discussion Educational score: 4.094818592071533 Domain: biomedical Document type: Study Language: en In this study, cases of acute febrile illness, pneumonia, and enteric fever were associated with CDI development, likely due to the widespread use of broad-spectrum antibiotics and prolonged hospital stays. Remarkably, the majority of toxin-positive cases in our study lacked underlying comorbidities, indicating that CDI can affect individuals regardless of their health status. The mean duration of hospitalization among ELISA-positive cases was significantly longer (8.0 ± 1.53 days) than that of ELISA-negative cases (3.75 ± 1.25 days). The strong association between hospitalization duration and CDI positivity highlights the role of prolonged hospital stays as a risk factor for CDI acquisition, which is consistent with research conducted by Choudhury et al., emphasizing the importance of hospital infection control measures and antimicrobial stewardship programs . Section title: Discussion Educational score: 4.098270893096924 Domain: biomedical Document type: Study Language: en Our study highlighted antibiotic exposure as a critical risk factor for CDI, as all toxin-positive cases (100%) were exposed to broad-spectrum antibiotics during hospitalization. Third-generation cephalosporins were the most frequently implicated antibiotic class, in line with findings from studies showing an association between cephalosporin use and CDI incidence . This reinforces the need for cautious and judicious antibiotic prescribing practices to mitigate CDI risk in hospital settings. Section title: Discussion Educational score: 4.046573638916016 Domain: biomedical Document type: Study Language: en The development of gastrointestinal symptoms after 72 hours of hospitalization was significantly associated with CDI in our study, consistent with findings from previous research . Additionally, the presence of fecal leukocytes in stool samples from CDI-positive patients indicated an inflammatory response, which is commonly associated with CDI. However, studies by Reddymasu et al. have noted the poor predictability and low sensitivity of fecal leukocyte counts for CDI detection . Section title: Discussion Educational score: 1.559439778327942 Domain: biomedical Document type: Other Language: it Limitations Section title: Discussion Educational score: 3.761319398880005 Domain: biomedical Document type: Study Language: en Our study had a few limitations. The study duration was short, and the sample size was relatively small. Only ELISA was employed for CDI detection, and we only included patients from indoor wards. Including patients from all hospital wards and ICUs could provide a more comprehensive analysis of CDI trends. Furthermore, molecular testing, such as PCR for toxin gene detection, is more sensitive and specific, and using this method might yield a more accurate CDI rate. Section title: Conclusions Educational score: 4.123003005981445 Domain: biomedical Document type: Study Language: en The present study provides valuable insights into the incidence rate, risk factors, and clinical characteristics of CDI among hospitalized patients. The incidence of CDI was found in one-tenth of the study population. Patients admitted with provisional diagnoses of acute febrile illnesses and pneumonia were more likely to develop CDI. Significant factors for CDI development included the use of third-generation cephalosporins and longer hospitalization durations. These findings suggest that targeted interventions are needed to reduce CDI incidence and associated morbidity and mortality. The results emphasize the importance of implementing effective infection control measures, including hand hygiene, contact precautions, surface disinfection, antimicrobial stewardship programs, and diagnostic strategies to mitigate the CDI burden in healthcare settings. Further research is needed to explore CDI diagnostics, risk factors, pathogenesis, and community-acquired CDI to develop targeted diagnostic, therapeutic, and preventive strategies. | Other | biomedical | en | 0.999998 |
PMC11698572 | Section title: Introduction Educational score: 4.13555908203125 Domain: biomedical Document type: Study Language: en Feeding practices and growth patterns during the early months of life are linked to future body mass index levels . Rapid weight increase in the initial months is a predictor of obesity in later years . Current recommendations suggest exclusive breastfeeding for the initial six months, followed by the gradual introduction of specific solid foods, which is associated with reduced fat mass in children . Introducing solid foods earlier than recommended can lead to quick weight gain during infancy, potentially impacting the risk of obesity in childhood . Infants who followed dietary guidelines closely, consuming high amounts of fresh fruits and vegetables, meals prepared at home, and breast milk, experienced more significant weight and skin fold thickness increases between six and 12 months compared to their peers, regardless of the type of milk consumed, when solids were introduced, and maternal influences . Bioelectrical impedance (BIA) is a painless, non-invasive, and easily portable technique that may clarify how the human body is operational. Body composition (BC) assessment is commonly established as a clinical technique for evaluating and estimating disease status . Strong debates are still present about the effect of timing and type of introduction of complementary food on metabolic programming and later on obesity, so this study aimed to assess the effect of feeding practices in the first two years of life on the body composition of preschool-age children and to highlight the importance of using Bioelectrical Impedance Analysis (BIA) in clinical settings for identifying individuals at risk of overweight and obesity. Section title: Materials and methods Educational score: 1.3672782182693481 Domain: biomedical Document type: Other Language: da Study design Section title: Materials and methods Educational score: 3.720611333847046 Domain: biomedical Document type: Study Language: en This is a cross-sectional study that was carried out on preschool-aged children over one year from the 1st of January 2022 to the end of December 2022. The sample size was calculated using OpenEpi, Version 3, open source calculator-SSPropor, for proportion with the prevalence of exclusive breastfeeding of 28% and a total population of 350, and a confidence limit of 5%. The calculated sample was 165. A total coverage of all eligible children yielded only 160 children (with a dropout rate of 3%). Section title: Materials and methods Educational score: 1.8619040250778198 Domain: biomedical Document type: Study Language: en Inclusion criteria Section title: Materials and methods Educational score: 2.03784441947937 Domain: biomedical Document type: Study Language: en Children aged from three to five years old, born full terms with no history of chronic disease were included in our study. Section title: Materials and methods Educational score: 1.6803547143936157 Domain: biomedical Document type: Other Language: ro Exclusion criteria Section title: Materials and methods Educational score: 2.5573718547821045 Domain: biomedical Document type: Study Language: en Preterm children and full-term children who had an inborn error of metabolism or any chronic disease, congenital malformations, previous operative history, or those who were fed cow milk or buffalo milk were excluded. Section title: Materials and methods Educational score: 2.588852643966675 Domain: biomedical Document type: Other Language: en Breastfeeding is defined as exclusive breastfeeding for four months and continues until 12 months of age and beyond . Early introduction of the first food is giving complementary feeding to the baby before 17 weeks and late introduction of the first food is giving complementary feeding after 26 weeks . Section title: Materials and methods Educational score: 2.625922203063965 Domain: biomedical Document type: Study Language: en Data were collected by personal interviews with mothers of eligible children in the form of personal history (name, age, sex, and weight at birth), nutritional history that includes the type of feeding (exclusive breast, formula, or mixed feeding), and type and timing of first food introduced. Body composition analysis was done by using ACCUNIQ BC380 . Section title: Materials and methods Educational score: 1.4600969552993774 Domain: biomedical Document type: Other Language: en Statistical analysis Section title: Materials and methods Educational score: 4.0316162109375 Domain: biomedical Document type: Study Language: en Data were analyzed using IBM SPSS software package version 25.0 (IBM Corp., Armonk, NY, USA). Qualitative data were described using numbers and percent, using the Chi-square test as well as the Fisher's exact test for variables with small expected numbers. The Kolmogorov-Smirnov test was used to verify the normality of the distribution. Quantitative data were described using range (minimum and maximum), mean, and standard deviation, and then compared using an independent t-test or Mann-Whitney test for the analysis of data between two groups. One-way ANOVA if the comparison between more than two groups, significant level when the p-value <0.05. Receiver operating characteristic curve (ROC) was generated by plotting sensitivity (TP) on the Y axis versus 1-specificity (FP) on the X axis at different cut-off values. The area under the ROC curve denotes the diagnostic performance of the test. An area of more than 50% gives acceptable performance, and an area of about 100% is the best performance for the test. Section title: Materials and methods Educational score: 1.1117407083511353 Domain: biomedical Document type: Other Language: en Ethics approval and consent to participate Section title: Materials and methods Educational score: 1.4189484119415283 Domain: biomedical Document type: Other Language: en The study was approved by the ethics committee of the Faculty of Medicine, Assiut University . Written informed consents were taken from parents. Privacy and confidentiality of all obtained information were observed without intervention in the prescribed treatment. Section title: Results Educational score: 4.1076531410217285 Domain: biomedical Document type: Study Language: en The study included 160 full-term children; 91 of them were males (56.9%) with a mean birth weight of 3.00±0.48 kg. Breastfeeding was the most common feeding method in 83 children (51.9%) and the first food introduced to the children was vegetables and fruits in 98 children (61.3%) followed by yogurt in 35 children (21.9%). Regarding the time of the first food introduced, 42 children i.e. more than a quarter of children (26.25%) began complementary feeding early (before 17 weeks) while the majority of them (96 children, 60%) received complementary feeding at the optimum time. The average body composition for the subjects included 9.57 ± 1.83 kg of water, 2.54 ± 0.48 kg of protein, 0.88 ± 0.22 kg of minerals, 4.98 ± 2.07 kg of fat, and 5.67 ± 1.48 kg for skeletal muscle mass. The mean height, weight, and BMI of children were 105.23 ± 7.2 cm, 17.97 ± 3.50 kg, and 16.56 ± 1.79, respectively with 39.4% of children being overweight/obese (Table 1 ). Section title: Results Educational score: 4.061591625213623 Domain: biomedical Document type: Study Language: en Regarding factors affecting body composition, formula-fed children showed significantly higher body fat mass and mean BMI (p-values of 0.002 and 0.001, respectively). Neither the type nor timing of the first food introduced showed a significant difference in the body composition of children. As regards BMI classification, the percentage of infants with a normal BMI was significantly lower in the formula feeding group (40.9%) vs. in the breastfeeding (71.1%) and mixed feeding groups (50.9%). The percentage of infants who were obese or overweight was higher in the formula feeding group than in the other two groups with a significant association between being overweight/obese and formula feeding/mixed (p-value 0.003) (Table 2 ). Section title: Results Educational score: 2.783053159713745 Domain: biomedical Document type: Study Language: en Also, obesity was significantly associated with dairy products as the first type of food introduced to the child (p = 0.041) (Table 3 ). Section title: Results Educational score: 2.155292510986328 Domain: biomedical Document type: Study Language: en The timing of the first food introduced showed no significant effect on the body composition of children (Table 4 ). Section title: Results Educational score: 4.1073808670043945 Domain: biomedical Document type: Study Language: en With regards to the prognostic performance of BIA to discriminate overweight patients (n = 97) from normal BMI (n = 63), it was found that BIA has significantly excellent discrimination power for fat mass (p-value < 0.001 & AUC = 0.916). The cut-off point for body fat mass is ≥5.2, and it has a high sensitivity of 85.71% and specificity of 89.69%. The positive predictive value (PPV) is 84.4%, while the negative predictive value (NPV) is 90.6%. These results suggest that body fat mass is a good predictor for discriminating between overweight and normal BMI individuals . Section title: Discussion Educational score: 3.6023337841033936 Domain: biomedical Document type: Review Language: en Breastfeeding has been observed to have a modest but consistent protective effect against obesity in children . It is a well-established fact that traditional formula milk contains higher levels of protein compared to breast milk. Protein-rich formulas are considered a factor that can accelerate plasma insulin levels and lead to the release of insulin-like growth factor-1, consequently resulting in weight gain and later obesity . Section title: Discussion Educational score: 3.925297260284424 Domain: biomedical Document type: Study Language: en Aligning with findings from the present study, Malekzadeh et al. detected that despite similar weight for age and weight-for-length Z-score (WLZ) at birth in the studied groups, WLZ was significantly higher in the formula-fed group at six months of age, indicating that formula feeding can lead to higher weight gain than breast milk in infants . Section title: Discussion Educational score: 3.716543436050415 Domain: biomedical Document type: Study Language: en Li et al. found that predominantly formula-fed infants weighed more than the exclusively human milk-fed group at term-corrected age, and their greater change in weight Z-score throughout the study was accompanied by higher non-adipose tissue mass deposition . Section title: Discussion Educational score: 2.316101551055908 Domain: biomedical Document type: Study Language: en Contrasting these findings, Raju et al. stated that there is no significant difference in the weight of babies who are breastfed, formula-fed, or mixed-fed . Section title: Discussion Educational score: 4.03672981262207 Domain: biomedical Document type: Study Language: en When comparing the first food introduced (dairy product group, vegetable/fruit group, and fortified cereals group), the results indicated no significant differences in body composition measures between the three groups. A randomised trial studied the effect of feeding on body weight composition and insulin resistance and found that decreased weight was most associated with increased intake of legumes and decreased intake of total meat, fish, and poultry . Those consuming a low-fat vegan diet also increased their intake of carbohydrates, fibre, and several micronutrients and decreased fat intake. Reduced fat intake was associated with reduced body weight (r = +0.15; P = 0.02) . Section title: Discussion Educational score: 2.1778855323791504 Domain: biomedical Document type: Study Language: en The results show no significant differences in body composition among the early, optimum, and late introduction of the first food groups. This suggests that the timing of the first food introduction does not significantly impact body composition in infants. Section title: Discussion Educational score: 3.87837553024292 Domain: biomedical Document type: Study Language: en In the current study, the BMI of infants did not show significant differences based on the timing of food introduction. Similarly, a meta-analysis by Pearce et al. concluded that there is no clear association between the timing of introducing complementary foods and childhood overweight or obesity, although a very early introduction of solid foods (≤4 months of age) may result in an increase in childhood BMI . Section title: Discussion Educational score: 2.5349032878875732 Domain: biomedical Document type: Review Language: en A review by Qasem et al. found no difference in fat mass between groups that received complementary foods (CF) at 4 vs. 6 months of age when studied at six months of age . Section title: Discussion Educational score: 2.695028305053711 Domain: biomedical Document type: Review Language: en Contrasting these findings, an earlier review by Lanigan reported an increased fat mass at follow-up in seven-year-old children who had CF introduced before 15 weeks compared to six-year-old children who had CF introduced after five months . Section title: Discussion Educational score: 3.6056454181671143 Domain: biomedical Document type: Review Language: en However, two systematic reviews did not find a clear association between the timing of CF introduction and measures of adiposity, such as skin-fold thicknesses, fat mass, and percentage fat mass measured by dual-energy X-ray absorptiometry and/or bioelectrical impedance . Section title: Discussion Educational score: 4.096652507781982 Domain: biomedical Document type: Study Language: en In the current study, the prognostic performance of BIA to discriminate overweight children from normal BMI was evaluated; the AUC for skeletal muscle mass is 0.655, indicating that it has a fair statistically significant discrimination power (P = 0.043). The cut-off point for skeletal muscle mass is ≥5.7, and it has a sensitivity of 65.08% and specificity of 52.58%. The PPV is 47.1%, and the NPV is 69.9%. These results suggest that skeletal muscle mass is a less reliable predictor than body fat mass in discriminating between overweight and normal BMI individuals. Section title: Discussion Educational score: 3.032043695449829 Domain: biomedical Document type: Study Language: en Aligning with this study, Khan et al. found that BIA machines vary in relative accuracy when measuring body composition in children who are obese and severely obese . Section title: Discussion Educational score: 4.03275728225708 Domain: biomedical Document type: Study Language: en However, two other studies in obese/severely obese children demonstrated an underestimation of body fat percentage using an SF4 BIA device (Omron Portable Fat Analyser; Omron, Dongguan, China) or an alternate MF4 BIA (Tanita MC-180MA; Tanita, Dongguan, China) device compared to DXA, with similarly wide limits of agreement (−15 to +5%). de Silva et al., using their MF4 BIA machine-generated resistance data with both published paediatric-specific and their own derived equations for estimating body fat and free fat mass, were able to reduce systematic bias to <1%, but the limits of agreement remained wide (−9 to +9%) . Section title: Discussion Educational score: 1.7324336767196655 Domain: biomedical Document type: Other Language: en Limitations of the study Section title: Discussion Educational score: 2.049551248550415 Domain: biomedical Document type: Study Language: en Only the first food introduced was asked for and not attaining a history of subsequent diets given to infants as detailed food history would be subjected to recall bias. Weight and height at the beginning of the study weren’t correlated to growth charts to determine whether it was normal for age or not. Finally, the study was conducted in an international school with a relatively high socioeconomic class compromising the variation in feeding type and practices by socioeconomic levels. Section title: Conclusions Educational score: 3.896036148071289 Domain: biomedical Document type: Study Language: en Breastfeeding has a protective effect against the risk of obesity in children where formula-fed children have higher body fat mass and BMI than breastfed. A greater proportion of infants who started food with cereals had a normal BMI, in contrast to groups that started with dairy products and were mostly obese. Body fat mass as detected by BIA is a good predictor for obesity, and skeletal muscle mass is less reliable for discriminating between overweight and normal BMI individuals than body fat mass in obese. | Study | biomedical | en | 0.999998 |
PMC11698603 | Section title: 1. Introduction Educational score: 4.607817649841309 Domain: biomedical Document type: Review Language: en The temporomandibular joint (TMJ) is among the most complex joints in the human body and serves as a crucial growth site within the craniofacial complex due to its unique anatomical, histological, and biomechanical properties. Its cartilaginous tissue is capable of remodeling in response to external forces, even after growth has ceased. Therefore, the condyles are not only primary targets in orofacial orthopedics, but also key determinants of long-term stability in orthognathic surgeries. TMJ morphology can vary significantly among individuals and may even differ between the right and left sides of the same individual. Given the close relationship between form and function, orthodontists often anticipate a correlation between condylar characteristics and craniofacial morphology . The morphology and position of the TMJ are critical for the stability of orthodontic treatments and can be influenced by several factors, including age, gender, growth patterns, muscular activity, and occlusal changes . The type of skeletal pattern can impact the morphology and position of the condyle and the glenoid fossa . The ANB angle is a recognized cephalometric measurement used to evaluate the anteroposterior relationship between the maxilla and mandible. Clinically, this angle is crucial for diagnosing skeletal relationships. Its measurement provides insight into whether a patient has a Class I, Class II, or Class III skeletal pattern, which in turn influences the therapeutic approach in both orthodontics and maxillofacial surgery. The ANB angle is a key factor in clinical treatment decision-making. Some studies found significant correlations between ANB and masticatory function, including masseter muscle activity and abnormal chewing patterns. These results highlight the ANB angle's role in determining treatment type, helping clinicians decide between camouflage orthodontics and surgical intervention . Some studies have explored the correlation between serological variables and temporomandibular disorders (TMDs) in patients with systemic and chronic autoimmune diseases, such as rheumatoid arthritis (RA), which involve inflammation of the synovial joints. Certain serological factors may serve as predictive markers for specific TMDs . Section title: 1. Introduction Educational score: 3.9723103046417236 Domain: biomedical Document type: Review Language: en Imaging plays a crucial role in accurate diagnosis. Conventional radiographic techniques used in orthodontic treatments, such as cephalometry and panoramic radiography, do not provide a clear, multidirectional view of the TMJ . Cone beam computed tomography (CBCT) has proven valuable in detecting significant changes in condyle position in patients with TMJ disorders . CBCT allows for the assessment of TMJ anatomy without the superimposition of structures, thereby, facilitating the analysis of bone structure, joint space, and dynamic function in three dimensions. This technology surpasses the limitations of other imaging techniques like panoramic radiography and traditional computed tomography . Section title: 1. Introduction Educational score: 4.268784523010254 Domain: biomedical Document type: Review Language: en Various studies have examined the relationship between skeletal malocclusions and TMJ morphology, highlighting significant differences across Angle's classifications. For instance, some studies found that patients with Class III malocclusion exhibited significant changes in joint space, with a more anteriorly displaced condyle compared to those with Class I or II malocclusions . Differences in condylar morphology, joint space, and fossa dimensions between skeletal patterns, suggesting that these variations could play a role in the development of TMDs across different skeletal classes. In particular, class III subjects were characterized by a wider mandibular fossa and a more superior condylar position, whereas Class II patients showed more pronounced changes in joint space and condylar height . The morphology and position of the condyles are significant in orthodontics as they can influence the outcomes and stability of orthodontic treatments . The ideal position of the condyle within the glenoid fossa remains a fundamental question in dentistry . There is ongoing debate regarding the clinical importance of condylar positioning in the TMJ. The position of the condyle is the result of various dynamic processes, including growth, remodeling, and responses to functional and occlusal changes [ 15 – 17 ]. The impact of occlusion on the condyle–fossa relationship continues to be a subject of research. Some studies have recognized the role of occlusion in the relationship between the condylar process and the mandibular fossa [ 18 – 20 ]. Beyond the position, occlusion may also be associated with the vertical height, anteroposterior, and mediolateral thickness of the condylar head . The condyle–fossa relationship may or may not be associated with variables such as sex, age, and laterality (left and right sides), as suggested by various studies . Section title: 1. Introduction Educational score: 3.8852367401123047 Domain: biomedical Document type: Study Language: en Orthognathic surgeries and growth modification treatments can affect the position of the condyle and the dimensions of the joint spaces. Numerous studies have indicated that orthognathic surgeries can alter the position of the condyle within the joint space, though these changes are often not significant in the long term . However, other studies have reported that such changes can be significant even over the long term . Changes in condylar position and joint spaces can impact the recurrence of surgical outcomes [ 27 – 29 ]. Growth modification treatments can also alter the position of the condyle, potentially causing its displacement . Furthermore, the correction of Angle's Class I malocclusions using fixed orthodontic appliances has been associated with significant posterior movement of the condyle. The posttreatment position of the condyle is crucial as it can aid orthodontists in predicting the condylar position during treatment planning . Section title: 1. Introduction Educational score: 4.09873628616333 Domain: biomedical Document type: Study Language: en Significant variations in the dimensions and spatial orientation of the mandibular condyles within the glenoid fossae have been observed between male and female subjects with different sagittal skeletal relationships. These morphological differences, as demonstrated through CBCT analysis, are likely to correlate with specific malocclusion classifications. Consequently, these anatomical variations may influence the efficacy and long-term stability of orthodontic interventions. Therefore, understanding the extent of joint spaces and the condylar position across different anterior–posterior skeletal patterns is essential for optimizing outcomes in orthognathic surgery and growth modification treatments, aiding orthodontists and surgeons in treatment planning. Additionally, there is still a gap in comprehensive knowledge regarding the relationship between TMJ morphology and various types of malocclusions, particularly within the Iranian population. The aim of this study is to evaluate and compare the size and position of the right and left condyles in the glenoid fossa among male and female patients with different skeletal patterns in the anterior-posterior dimension using CBCT images. Section title: 2. Materials and Methods Educational score: 1.059536337852478 Domain: biomedical Document type: Other Language: en This study was approved by the Ethics Committee of Shahid Beheshti University of Dental Medicine under the approval number IR.SBMU.DRC.REC.1401.021. Due to the retrospective nature of the study and the anonymization of patients' data in the final report, specific ethical considerations were not applicable. Section title: 2. Materials and Methods Educational score: 3.972787618637085 Domain: biomedical Document type: Study Language: en From March 2019 to April 2023, a total of 153 CBCT images were collected from two oral and maxillofacial centers. The inclusion criteria required appropriate image quality, coverage of the examined area, symmetrical skeletal appearance, complete dentition (with or without the third molars), and participants aged over 16 years. Exclusion criteria included evidence of trauma or surgery, crossbite or open bite, a history of orthodontic or orthopedic treatment, congenital syndromes, and craniofacial deformities. Ultimately, 119 images (33 males and 86 females) met the criteria and were analyzed in the study. Section title: 2. Materials and Methods Educational score: 4.059783935546875 Domain: biomedical Document type: Study Language: en Based on the ANB angles, the samples were categorized into three groups: Class I ( n = 49), Class II ( n = 52), and Class III ( n = 18). The classifications were defined as follows: ANB < 0 for Class III, 0 < ANB < 4 for Class I, and ANB > 4 for Class II. For borderline cases, an additional Wits analysis was performed. In this analysis, Points A and B were projected perpendicularly onto the functional occlusal plane in the midsagittal section of the three-dimensional view, and the distance between these points was measured. Individuals were categorized as Class I if the measurement ranged from −1 to 1, Class II if greater than 1, and Class III if less than −1. In cases where discrepancies existed between Steiner and Wits analyses, the Wits analysis was used as the primary reference. Section title: 2. Materials and Methods Educational score: 4.110334396362305 Domain: biomedical Document type: Study Language: en The CBCT images were acquired using a CBCT device (HDX-WILL, South Korea) with a field of view (FOV) of 14.5 cm × 16 cm and exposure settings of 110 kVp, 17 s exposure time, voxel size of 300 µm, and a current of 4 mA. Participants were instructed to remain still, refrain from swallowing, and maintain centric occlusion with relaxed lips and tongue during imaging. The images were analyzed using the OnDemand3D software (version 10.1). The Frankfurt plane was aligned parallel to the horizontal plane. The horizontal reference axis of the condyle was established by selecting the innermost and outermost points of the condyle head in the axial section . Based on this reference, the condyle and articular eminence were examined in three planes: axial, coronal, and sagittal, for both the right and left joints. Section title: 2. Materials and Methods Educational score: 4.103172302246094 Domain: biomedical Document type: Study Language: en In the sagittal plane, the upper joint space was determined by measuring the distance between the SG point (located at the top of the glenoid fossa) and the SC point . Additionally, in this plane, a line tangent to the anterior edge of the condyle head was drawn from the SG point, intersecting at a point designated as AC. A perpendicular line from AC to the anterior wall of the glenoid fossa was measured as the anterior articular space . Similarly, a tangent line from the SG point to the posterior limit of the condyle head identified a point called PC. A perpendicular line from PC to the posterior wall of the glenoid fossa was measured as the posterior articular space . Section title: 2. Materials and Methods Educational score: 3.992805004119873 Domain: biomedical Document type: Study Language: en In the coronal plane, from the SC point, a line was drawn perpendicular to a line connecting the MC point (the most medial part of the condyle head) and the LC point (the most lateral part of the condyle head), measuring the height of the condyle . The width of the condyle was determined by measuring the distance between the MC and LC points in the coronal plane . In the sagittal plane, the length of the condyle was measured as the distance between the AC and PC points . Section title: 2.1. Sample Size Calculation Educational score: 3.996062755584717 Domain: biomedical Document type: Study Language: en The sample size for this study was determined using PASS15 software for a one-way ANOVA design. The parameters used for calculation were a type I error rate ( α ) of 0.05 and a type II error rate ( β ) of 0.2 (80% power). The following parameters were considered for the main dependent variable: • Mean for Group 1 ( μ 1 ): 18.48 • Mean for Group 2 ( μ 2 ): 17.01 • Mean for Group 3 ( μ 3 ): 18.55 • Standard deviation ( σ ): 2.78 Section title: 2.1. Sample Size Calculation Educational score: 4.031318664550781 Domain: biomedical Document type: Study Language: en Based on these parameters, the sample size calculation for each group was conducted using the formula for a one-way ANOVA: n = 2 σ 2 Z α / 3 + Z β 2 μ 1 − μ 2 2 , where Z α /3 is the critical value of the standard normal distribution at α /3 to adjust for multiple comparisons (for three groups). Section title: 2.1. Sample Size Calculation Educational score: 2.615736484527588 Domain: biomedical Document type: Study Language: en Using the provided parameters, the calculated sample size per group was 51. Accounting for potential dropouts and to ensure adequate power, a total sample size of 153 participants (51 per group) was determined. Section title: 2.2. Statistical Analysis Educational score: 4.047154903411865 Domain: biomedical Document type: Study Language: en The position (superior–anterior–posterior articular space) and size (width–height–length of the condyle) were measured for each individual on both the right and left sides using OnDemand software. The average measurements were recorded. Statistical analyses were performed using SPSS software (version 24.0 for Windows). The Shapiro–Wilk test was utilized to assess the normality of data distribution, while Levene's test was applied to evaluate the equality of variances. A T -test was conducted to compare gender differences across various skeletal patterns. The Bonferroni method was employed for pairwise comparisons of the dependent variables across different skeletal patterns. An analysis of covariance (ANCOVA) was used to examine the effects of variables such as gender and different skeletal patterns on the dependent variables, adjusting for the impact of age. Statistical significance was set at p < 0.05. Section title: 3. Result Educational score: 2.506544351577759 Domain: biomedical Document type: Study Language: en CBCT images of 119 patients, consisting of 86 women (72.5%) and 33 men (27.5%), were analyzed. The participants ranged in age from 16 to 77 years, with an average age of 32.86 years ( Table 1 ). Section title: 3. Result Educational score: 4.028809547424316 Domain: biomedical Document type: Study Language: en Different skeletal patterns did not show a statistically significant effect on the superior space (SS; p = 0.392). However, a statistically significant difference in SS was observed between genders, with men exhibiting a higher SS compared to women ( p ≤ 0.001). The interaction between gender and skeletal patterns was not statistically significant ( p = 0.337), but SS values were consistently higher in men than in women. The analysis indicated that the impact of different skeletal patterns was not significant in women ( p = 0.443) or men ( p = 0.367; Table 2 ). Section title: 3. Result Educational score: 3.9223005771636963 Domain: biomedical Document type: Study Language: en Similarly, different skeletal patterns ( p = 0.481), gender ( p = 0.386), and the interaction between them ( p = 0.257) did not significantly affect the anterior space (AS). The influence of different skeletal patterns was not significant in women ( p = 0.236) or men ( p = 0.196; Table 2 ). The evaluation of gender effects within each skeletal pattern group revealed a statistically significant difference only in the Class I group ( Table 3 ). Section title: 3. Result Educational score: 4.04740047454834 Domain: biomedical Document type: Study Language: en For posterior space (PS), different skeletal patterns ( p = 0.027) and gender ( p = 0.001) had statistically significant effects. However, the interaction between them did not significantly impact PS ( p = 0.556). PS values were consistently higher in men than in women, with the skeletal pattern differences ranked as follows: Class III > Class II > Class I. A significant difference was noted only between the Class I and Class III groups, with the PS value being lower in Class I compared to Class III; no other group comparisons showed statistically significant differences ( Table 4 ). Section title: 3. Result Educational score: 4.092890739440918 Domain: biomedical Document type: Study Language: en There were no significant effects of different skeletal patterns ( p = 0.367), gender ( p = 0.100), or the interaction between them ( p = 0.825) on the height of the condyle ( Table 5 ). However, gender had a significant effect on condyle width, with men consistently showing a larger condyle width than women ( p ≤ 0.001). The interaction between gender and skeletal patterns did not significantly affect condyle width ( p = 0.720; Table 5 ). Different skeletal patterns significantly influenced condyle length ( p = 0.002), though gender ( p = 0.198) and the interaction between gender and skeletal patterns ( p = 0.851) did not ( Table 5 ). Significant differences in condyle length were observed between Class I and Class II and between Class II and Class III, with Class II exhibiting the lowest values ( Table 6 ). Section title: 4. Discussion Educational score: 4.0005292892456055 Domain: biomedical Document type: Study Language: en Our study investigated the relationship between the morphology and position of the condyle and different skeletal patterns in the sagittal dimension using CBCT images. The morphology and position of the condyle are critical features in diagnosing and planning treatment for issues related to the TMJ. Various factors, such as gender, erosion, hyperplasia, and different syndromes, can affect the morphology of the condyle. The impact of condylar morphology and position on the function of the masticatory system and the development of malocclusions has been extensively researched. However, comprehensive knowledge of the relationship between TMJ morphology and various types of malocclusions, especially in the Iranian population, remains limited. Section title: 4. Discussion Educational score: 4.086771488189697 Domain: biomedical Document type: Study Language: en Systemic diseases, such as RA, can significantly alter the dimensions and positioning of TMJ structures. Youssef Mohamed et al. identified that patients with RA exhibited significantly reduced condylar height and increased radiographic osteoarthritic changes compared to a control group. Additionally, there was a significant inverse correlation between anticitrullinated protein (ACCP) levels, disease activity score 28 (DAS28), and high to moderate disease activity with condylar anteroposterior dimensions. Consistent with these findings, our study demonstrated that individuals with a Class II skeletal pattern had significantly shorter condylar lengths compared to other skeletal groups. Moreover, our results corroborated Youssef Mohamed et al.'s observation that ACCP levels did not significantly correlate with mediolateral dimensions. Furthermore, we found no statistically significant differences in condylar height and width across various skeletal patterns. Section title: 4. Discussion Educational score: 4.058765411376953 Domain: biomedical Document type: Study Language: en Previous research has provided important insights into how TMJ morphology is clinically relevant in individuals with different skeletal malocclusions. Variations in condylar position and joint space across skeletal classes may contribute to an increased risk of TMDs in specific populations. For instance, Song et al. found that Class III malocclusions were linked to more anteriorly positioned condyles and reduced joint space, which could lead to higher stress on the TMJ and worsen TMD symptoms. In contrast, Alhammadi, Fayed, and Labib found that Class II patients exhibited larger condylar height and anterior joint space, potentially presenting different biomechanical challenges. Additionally, they highlighted the importance of understanding the three-dimensional aspects of TMJ morphology, as both Class II and Class III patients showed notable differences in condylar and fossa dimensions, which may influence orthodontic treatment decisions and TMD management. Section title: 4. Discussion Educational score: 4.123837947845459 Domain: biomedical Document type: Study Language: en In alignment with Chae et al. , the current study found no statistically significant differences between the size of the upper joint space and different skeletal patterns. Akbulut and Kılınç reported that the superior joint space, defined as the distance from the condyle to the fossa, had the highest values in Class II subjects on both sides, with statistical significance on the right side but not on the left. Tariq and Jan observed that the upper joint space was smallest in Class III subjects and largest in Class I subjects. Arieta-Miranda et al. and Song et al. also reported the highest values in Class I individuals, but contrary to their findings, did not find significant differences between Class II and Class III individuals. In our study, there was no statistically significant difference between the size of the anterior joint space and malocclusion, consistent with studies conducted by Chae et al. and Song et al. . Arieta-Miranda et al. used different landmarks from our study to measure the anterior space and concluded that Class I individuals have the largest amount of anterior space compared to Class II and Class III individuals. Posterior joint space values in Class I individuals were significantly lower than those in Class III subjects, aligning with the findings of Tariq and Jan . Contrary to our results, studies by Chae et al. , Akbulut and Kılınç , and Arieta-Miranda et al. found no statistically significant differences in the size of the posterior joint space across different skeletal patterns. Akbulut and Kılınç and Arieta-Miranda et al. used the external auditory canal as the posterior border of the posterior joint space. Discrepancies in joint space size between our study and others can be attributed to differences in sample size and racial variations. Section title: 4. Discussion Educational score: 4.108252048492432 Domain: biomedical Document type: Study Language: en This study found no statistically significant differences in condylar height across different skeletal patterns. In contrast, Song et al. reported that Class I individuals had the highest condylar height values, using the same measurement method as ours. This difference may be attributed to racial variations. Hasebe et al. and Santander et al. , who used different landmarks than the present study to define condylar height, concluded that condylar height was greatest in Class III individuals. There was no statistically significant difference in condylar width across different skeletal patterns, similar to the findings of Chae et al. . However, other studies have reported different results. Our study found a statistically significant relationship between condylar length and different skeletal patterns, with Class II individuals exhibiting lower condylar length values than Class III and Class I individuals. Hasebe et al. and Tariq and Jan measured condylar length using the AC and PC points, selected on the anterior and posterior limits of the condyle head at a distance of 4 mm from the uppermost point of the condyle head in the sagittal dimension, and found no statistically significant difference between the three groups. In contrast, Song et al. , using the most anterior and posterior points of the condyle head in the axial dimension, concluded that Class I individuals have the highest values. Santander et al. and Chae et al. used methods similar to ours, connecting the most anterior and posterior points of the condyle head in the sagittal dimension. Santander et al. concluded that Class III individuals have the lowest values, whereas Chae et al. found no statistically significant differences between the three groups. The differences in results between our study and others may be due to variations in measurement methods and inclusion and exclusion criteria. For example, Chae et al. excluded cases with discrepancies between CO-CR and underlying diseases affecting metabolism, which were not considered in the present study. Section title: 4. Discussion Educational score: 4.065940856933594 Domain: biomedical Document type: Study Language: en A limitation of this study is the unequal distribution of male and female participants across skeletal classes, with an overrepresentation of Class II in females. This imbalance may affect the generalizability of the findings and limiting their interpretability. Future studies with a more balanced gender distribution are recommended for more reliable conclusions on the relationship between TMJ morphology and skeletal patterns. The limited number of Class III individuals and the lack of access to patient histories to account for other potential factors, such as TMD, in the development of skeletal malocclusions were another limitations of this study. Future studies should include larger sample sizes from various regions and consider additional factors that may influence the development of different skeletal patterns in the sagittal, vertical, and transverse dimensions. Section title: 5. Conclusion Educational score: 3.71431040763855 Domain: biomedical Document type: Study Language: en Based on the results of this study, Class I individuals had smaller posterior joint space compared to Class III individuals, while Class II individuals had shorter condyle length than both Class I and Class III. These findings emphasize the role of skeletal patterns in TMJ morphology, with potential implications for orthodontic treatment and TMJ disorder management. | Review | biomedical | en | 0.999994 |
PMC11698605 | Section title: 1. Background Educational score: 4.082538604736328 Domain: biomedical Document type: Study Language: en Complications, such as arterial puncture, pneumothorax, hemothorax, and infections, are reported to occur less frequently with the placement of peripherally inserted central venous catheters ([CVCs] PICCs) than with the placement of other CVCs . The use of PICC has increased in clinical settings, including during the perioperative period. Consequently, more patients undergo surgery under general anesthesia with PICCs inserted presurgically. PICC use has become more widespread due to newly introduced and more convenient insertion techniques, such as those adopting passive magnet tracking and the electrocardiogram (ECG)-guided tip confirmation system (TCS) , which facilitates catheter placement at the bedside without confirmatory imaging, and insertions performed by trained nurse practitioners. It is well known that guidewires used during PICC placement may cause cardiac arrhythmias if they progress too far into the right atrium (RA) . There are limited case reports on positional change–related arrhythmias as the insertion of PICCs is usually performed in awoken patients . Moreover, arrhythmias that occur during general anesthesia and are induced by a catheter inserted with the TCS-guided technique have not been reported. Section title: 1. Background Educational score: 3.8834731578826904 Domain: biomedical Document type: Clinical case Language: en Arrhythmias related to PICCs are rare. In three cases , nonsustained ventricular tachycardia (VT) occurred in awoken patients when their body positions were changed following PICC placement and confirmation of the tip position in the lower superior vena cava (SVC) by fluoroscopy or chest radiography. We presented a case of nonsustained VT that developed after a change in the patient's position under general anesthesia. We also discussed the factors affecting positional change–related arrhythmias in patients with preoperatively inserted PICCs using TCS and suggested possible measures for their prevention and treatment. Section title: 2. Case Presentation Educational score: 3.9681198596954346 Domain: clinical Document type: Clinical case Language: en The patient was a 44-year-old woman (height 155 cm and weight 62 kg) scheduled for laparoscopic right adrenalectomy for primary aldosteronism. She had no previous history of arrhythmia and had not taken any medications that cause arrhythmias. On the day before surgery, a PICC (PowerPICC, Becton, Dickinson and Company, NJ, USA) was inserted via the right brachial–basilic vein and the Sherlock 3CG TCS (Becton, Dickinson and Company, NJ, USA) was used to confirm the position of the catheter tip. It was placed 41 cm from the insertion site based on the maximal P -wave on the ECG, observed after confirmation of P -wave inversion. The correct position of the tip was then confirmed using chest radiography . After induction of anesthesia, when the patient was placed in the left lateral decubitus position with adduction followed by internal rotation of her right shoulder and flexion of the elbow, monomorphic nonsustained VT occurred . With further, almost maximal, internal rotation of the shoulder, the arrhythmia ceased, and the surgery was commenced as planned. Intraoperatively, the right atrium (RA) and right ventricle (RV) pressures were measured using a PICC lumen . The data indicated respiration-related movements of the catheter in the RV; however, no further arrhythmias were observed. When the patient was returned to the supine position after surgery, arrhythmia did not occur, and the postoperative course was uneventful. Section title: 3. Discussion Educational score: 4.110723495483398 Domain: biomedical Document type: Review Language: en “The Practical Guidelines for Safe CVC Placement and Management” issued by the Japanese Society of Anesthesiologists recommend Zone B , an area around the junction of the left and right innominate veins and the upper SVC, as the optimal position of the catheter tip following insertion ; these guidelines pertain to all CVCs and do not particularly focus on PICC tips. The European Society for Clinical Nutrition and Metabolism guidelines also pertain to all CVCs, presumably including PICCs, and accordingly, the adequate site for catheter placement is when “the tip is in the lower third of the SVC, at the cavoatrial junction (CAJ), or in the upper portion of the RA” . Similar recommendations are presented in “Safe Vascular Access ” (the United Kingdom), where the lower SVC or the upper RA position is considered optimal ; however, some American authors exclude the upper RA and limit the optimal position to the lower SVC and in the vicinity of the CAJ . Hence, adequate placement of the catheter, as recommended in the Japanese Society of Anesthesiologists guidelines, is slightly lower ; however, these guidelines have been established to reduce the frequency of CVC-related complications (vessel or myocardium perforations, thromboses, occlusions, catheter-related infections, pneumothorax, and arrhythmias) and are based on reported data where CVC tip positions were confirmed either with fluoroscopy or portable chest radiography. Section title: 3. Discussion Educational score: 4.081679344177246 Domain: biomedical Document type: Study Language: en With technological advancements in magnetic tracking and intracavity ECG, PICCs have recently been inserted at the bedside without postinsertion imaging. PICCs placed with the Sherlock 3CG TCS, where the tip position at the CAJ is considered correct according to the observed inversion of the electrocardiographic P -wave (NICE Medical Technology Guidance), tend to be inserted too far into the RA. Malpositioning of the catheter tip with the Sherlock 3CG occurs in 56.1% or 20.5% of patients, depending on the definition of the adequate tip position (low SVC/CAJ or mid SVC/low SVC/CAJ/high RA, respectively) . According to Johnston et al., malpositioning might be due to specific characteristics of the 3CG technology (targeting the CAJ, which is sometimes impossible to achieve in clinical settings), difficulty in defining the CAJ position on chest radiographs, and/or inconsistent CVC placement guidelines . Thus, even if the catheter is inserted and fixed in an optimal position, complications may still occur. Section title: 3. Discussion Educational score: 4.144959449768066 Domain: biomedical Document type: Clinical case Language: en In our case, PICC was inserted with the Sherlock 3CG TCS one day before surgery, and arrhythmia did not occur until the patient was positioned for the operation. Movements of the catheter tip (caudally up to 5.3 cm [or 2.2 rib spaces]) due to shoulder adduction have been reported, but only rarely induce VTs. The catheter tips constantly move according to the blood/injection fluid flow changes in the vicinity of the CAJ (lower risk of thrombosis) , or the upper RA might occasionally contact the atrioventricular (AV) node/RV wall; however, if this contact is only momentary, arrhythmia will presumably not occur. In contrast, in the lateral decubitus or prone position, contact with the AV node/RV wall may be sufficient to induce VT, which is not observed immediately after PICC insertion (usually in the supine position). A minor change in the body position (in our case, further adduction of the shoulder) might terminate the arrhythmia, but respiration- and blood flow–related movements would not cease . In an awoken patient, arrhythmia may produce symptoms such as shortness of breath, chest pain, or palpitations, and thus provoke a timely response . In contrast, in patients under general anesthesia, suspicion and vigilant observation of the ECG tracing when changing body position remain the only means of early recognition and treatment of PICC-induced arrhythmias. Simulation of the intraoperative position immediately after PICC insertion might allow detection of positional change–induced arrhythmias and prompt early correction of the catheter position (usually pulling back the catheter); however, this is not always feasible in clinical settings. Section title: 3. Discussion Educational score: 3.9101388454437256 Domain: biomedical Document type: Review Language: en Notwithstanding inconsistencies in CVC placement guidelines , TCS-guided PICC insertions seem to produce fewer instances of tip malpositioning and PICC-related complications. However, PICCs inserted with the Sherlock 3CG TCS tend to be extended further into the RA or RV than in conventionally placed PICCs under fluoroscopic or radiographic guidance and might induce arrhythmias on changing the patient's position. In patients under general anesthesia, such arrhythmias should be suspected and vigilant ECG monitoring should be performed. Placing the patient in the final intraoperative position immediately after PICC insertion may be reasonable, but further studies are required to assess the validity of its routine implementation. | Study | biomedical | en | 0.999996 |
PMC11698606 | Section title: 1. Introduction Educational score: 4.1257476806640625 Domain: biomedical Document type: Review Language: en Recently, foodborne-related diseases are the most common health concern for humans worldwide. Microbial deterioration and oxidative rancidity are the two major factors for spoilage of foods . During the 20th century, several new technologies and chemical compounds were developed for food preservation. However, pathogenic microorganisms in the food system continue to create multiple human diseases and cause substantial economic losses to food processors . At the same time, the indiscriminate use of antibiotics in human medicines, animal husbandry, and food industries against pathogenic bacteria has led to antimicrobial-resistant (AMR) development . AMR continues to develop more powerful mechanisms than ever and will be the major challenge shortly . Globally, AMR gets much attention among the research communities since it is widespread, reduces the therapeutic effect of these drugs within a shorter period, and leads to severe problems in the entire healthcare system . Therefore, AMR has been categorized as one of the top 10 public health threats to humans . Fatality rates due to AMR infections are increasing drastically, and it is expected to reach nearly 10 million per year by 2050. If no more effective and unique therapeutic methods are identified to contain AMR, there will be tremendous global economic losses . This situation forced the research communities to look back into traditional medicines or herbal products, which may provide appropriate and acceptable alternative solutions to maintain human health . Section title: 1. Introduction Educational score: 4.04518985748291 Domain: biomedical Document type: Review Language: en Oxidative rancidity is another factor for food spoilage during raw material handling, processing, and storage, which results in loss of nutritional quality, flavour, taste, and colour and leads to consumer rejections . Oxidized molecules in food systems are the causative agents for degenerative diseases such as arthritis, cancer, diabetes, multiple sclerosis, and cardiovascular-related diseases . Moreover, oxidation and rancidity are the biggest problems for the food industries, as they are directly involved in food waste generation and economic losses . To avoid these situations, synthetic additives have been widely used in industries due to their low cost, purity, and high activity at low concentrations. However, some harmful effects such as allergies, poisoning, and metabolic disorders have been reported when used in high doses . Therefore, it is necessary to find new antioxidant compounds that can be added to foods without affecting consumers' health. Recently, natural antioxidants have received greater attention in the research communities to prevent oxidative rancidity in food products. It could be one of the best options for food industries to replace synthetic antioxidants or preservatives, due to its bioavailability and health-beneficial effects. In addition, consumers' awareness of quality food products processed with natural preservatives has forced the food industries to focus on new natural preservatives in recent times. As a result, finding a new preservative with antioxidant and antimicrobial properties from natural sources is a primary goal for several researchers to benefit food processors and consumers. Section title: 1. Introduction Educational score: 4.128115653991699 Domain: biomedical Document type: Study Language: en India is the land of spices and herbs and has made a major contribution to world production. Wide ranges of spices are produced in India, with varying tropical climate conditions that make almost all spices grow splendidly. During 2021–2022, spices/spice products export reached around 1,531,154 tons, valued at $4102.29 million . Most spice extracts are in the form of essential oils (EOs). They are extensively used in folk medicines, food flavourings, and pharmaceutical applications. In addition, food industries use them as a natural preservative to extend storage stability without affecting the organoleptic properties [ 18 – 20 ], due to their unique properties, including antimicrobial, anti-inflammatory, antioxidant, and antitumour [ 21 – 23 ]. Some EOs are branded as generally recognized as safe (GRAS) by the Food and Drug Administration (FDA) and are considered potential alternatives to conventional antibiotics . However, a wide range of spices are cultivated in India, and their biofunctional properties and composition may vary due to several factors, such as variety, geographical conditions, maturity stage, and extraction methods, compared to worldwide production. In addition, the information on the antioxidant and antimicrobial component(s) of different Indian-origin EOs and their chemical compositions is minimal. Therefore, the current study is aimed at profiling the phytochemical composition and dual preservative properties, namely, antioxidant and antimicrobial properties, of four important commercial Indian-origin EOs, including clove, ginger, garlic, and eucalyptus. Section title: 2.1. Chemicals and Reagents Educational score: 1.5279814004898071 Domain: biomedical Document type: Other Language: en EOs such as clove, ginger, garlic, and eucalyptus were purchased from the local market. All the chemicals and reagents used as analytical research (AR) grade were obtained from Sigma–Aldrich, Merck, Hi-Media, and Qualigens. Section title: 2.2. Characterization of EOs by Gas Chromatography–Mass Spectrometry (GC–MS) Analyses Educational score: 4.131809234619141 Domain: biomedical Document type: Study Language: en The chemical profile of EOs was carried out using GC–MS analysis at ICAR-Indian Spice Research Institute, Kozhikode, India. For analysis, Restex 5MS capillary column having a length of 30 m × 0.25 mm inner diameter (ID), 0.25 μ of film thickness was used. The injector temperature was set at 250°C. GC oven temperature was programmed as follows: Initial holding temperature was kept at 60°C for 5 min, followed by heating temperature at 200°C for 3°C/min, and finally kept the constant temperature at 220°C for 7 min. The running time was set for 50 min, and Helium gas was used as a carrier gas with a steady flow speed (1.0 mL/min), and EOs (0.20 μ L) were injected into the instrument. An electron ionisation system with 70 eV ionisation voltage and a mass scanning range of 40–650 m/z was used for MS detection. The EO components were identified by comparing them with the NIST library or mass spectra from the literature . Section title: 2.3.1. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) Free Radical Scavenging Capacity Educational score: 4.09843635559082 Domain: biomedical Document type: Study Language: en The DPPH radical scavenging activity of EOs was measured according to Yen and Wu , with certain modifications. Briefly, an aliquot of 100 μ L EOs with various concentrations (20%–100% of ginger, garlic, and eucalyptus EOs and 1%–5% in clove EO) was added into 2 mL of methanolic DPPH (6 × 10 −5 M). Afterward, the mixtures were vortexed (Neuation Digital Vortex Mixer, iSwix VT, India) and kept in a dark place for 30 min at room temperature. Finally, absorbance was measured at 517 nm using a UV-VIS spectrophotometer . Methanolic DPPH solution was used as a control. The percentage inhibition was calculated using the following formula: % I = A control – A sample A control × 100 where I is the inhibition percentage of DPPH, A control is the absorbance of DPPH solution at 0 min, and A sample is the absorbance of DPPH solution with EOs after 30 min. Section title: 2.3.2. Ferric Reducing Antioxidant Power (FRAP) Activity Educational score: 4.087164878845215 Domain: biomedical Document type: Study Language: en The ferric-reducing capacity of different EOs was determined according to Benzie and Strain . Briefly, 20 μ L of EO with various concentrations (20%–100% of ginger, garlic, and eucalyptus EOs and 1%–5% in clove EO) were mixed into freshly prepared FRAP reagent (2 mL). Then, the mixture was mixed well and kept in a dark place for 4 min. Subsequently, the absorbance at 593 nm was measured using a UV-VIS spectrophotometer . FRAP reagent without EO was used as control. The obtained absorbance values were interpolated in a standard curve developed using iron (II) sulfate solution . The results were expressed as micromole Fe (II)/grams. Section title: 2.3.3. Total Phenolic Content (TPC) Educational score: 4.090665340423584 Domain: biomedical Document type: Study Language: en The TPC of EOs was calculated according to Singleton and Rosy . Briefly, 30 μ L of EOs with various concentrations (5%–25% ginger, garlic, and eucalyptus EOs and 1%–5% clove EO) were added into 3 mL distilled water and vortexed. Subsequently, the Folin–Ciocalteu reagent (0.5 mL) was mixed into the diluted EOs. After 3 min of incubation, 20% sodium carbonate (2 mL) was poured into the mixture and placed in a water bath for 1 min. Finally, absorbance at 650 nm was measured using a UV-VIS spectrophotometer . Catechol is used as a standard to plot the standard curve. The phenolic content was catechol equivalents in mg phenols/100 g of EOs. Section title: 2.4.1. Microorganisms and Culture Educational score: 3.559481620788574 Domain: biomedical Document type: Study Language: en The bacterial strains— Staphylococcus aureus , methicillin-resistant Staphylococcus aureus (MRSA) , Bacillus cereus (lab isolate), Salmonella enterica typhi , Vibrio cholera , Escherichia coli , Pseudomonas aeruginosa , and Aeromonas hydrophila —were procured from Microbial Type Culture Collection and Gene Bank (MTCC), Chandigarh, India. All the cultures were conserved at 4°C and kept alive by continuous subculture on a nutrient agar medium. Section title: 2.4.1. Microorganisms and Culture Educational score: 4.024402618408203 Domain: biomedical Document type: Study Language: en For the antimicrobial study, brain heart infusion (BHI) broth was inoculated with test bacterial culture, which was then cultured for 24 h at 37°C. Normal saline was used to adjust the bacterial culture turbidity (1.5 × 10 8 CFU/mL) with 0.5 McFarland standard turbidity. Section title: 2.4.2. Agar Well Diffusion Method Educational score: 4.103482246398926 Domain: biomedical Document type: Study Language: en The antibacterial properties of EOs were employed with the agar well diffusion method against food-borne and fish-borne bacteria such as S. aureus , MRSA, B. cereus , S. typhi , V. cholera , E. coli , P. aeruginosa , and A. hydrophila . Briefly, the bacterial cell suspension (1.5 × 10 8 CFU/mL) was spread over Mueller–Hinton agar (MHA) (HiMedia, India) plates and followed by 6 mm diameter wells prepared using sterile cork borer. Subsequently, 100 μ L of EOs and the control were poured into each empty well. Then, the plates were incubated at 37°C for 24 h. Finally, the inhibition zone ( n = 4) was measured using a standard antibiotic zone scale (PW 096, Hi Media). Section title: 2.4.3. Evaluation of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) Educational score: 4.157631874084473 Domain: biomedical Document type: Study Language: en Resazurin microdilution assay was carried out to measure the MIC values of EOs against food-borne and fish-borne bacterial strains such as S. aureus , MRSA, B. cereus , S. typhi , V. cholera , E. coli , P. aeruginosa , and A. hydrophila . In summary, an aliquot of 100 μ L Mueller–Hinton broth (MHB) (HiMedia, India) was filled into 96 well plates and followed by 200 μ L of EOs and 20 μ L of Tween 20 as an emulsifying/solubilizing agent was added into the first well. Further, serial dilution (100% to lower level) was carried out until the last well. At last, 30 μ L (approx. 3.0 × 10 6 CFU/mL) of bacterial suspension (0.5 McFarland standard adjusted) was added to each well and mixed thoroughly. After overnight incubation at 37°C, resazurin solution (30 μ L) was added into each well and incubated further at 37°C for 1 h. The MIC values are defined as the lowest concentration before the colour change. To determine MBC, a loopful of inoculum was taken from wells before the colour change and streaked on MHA plates. Then, the plates were incubated for 24 h at 37°C. The lowest concentration, which has no bacterial growth on the MHA plates, was considered MBC. Section title: 2.5. Statistical Analyses Educational score: 3.353527784347534 Domain: biomedical Document type: Study Language: en The results are expressed in mean ± standard deviation ( n = 3). The variance among the samples was analyzed using a one-way analysis of variance (ANOVA), and a comparison of mean values was performed by Duncan's multiple range test ( p ≤ 0.05). Section title: 3.1. Chemical Constituents of EOs Educational score: 4.153822422027588 Domain: biomedical Document type: Study Language: en The chemical constituents of ginger, clove, eucalyptus, and garlic EOs with retention time and percentage share in the sample are represented in Tables 1 and 2 . About 31 components were identified from ginger EO, comprising more than 94% of the EO composition ( Table 1 ). The most abundant compounds included α -zingiberene (28.01%), β -sesquiphellandrene (18.09%), β -bisabolene (9.72%), α -farnesene (7.40%), and β -citral (5.48%), which represents about 68.70% of the total EO compounds. The findings agree with previous studies in ginger EO containing α -zingiberene and β -sesquiterpene as principal components (10%–60%) responsible for different bioactivities such as antioxidant and antimicrobial properties . They can be used as a natural, long-lasting food preservative. Similarly, citral is another precarious compound identified from ginger EO, which inhibits much bacterial and fungal growth by reducing ATPase interactions, mitochondrial structural alteration, and cell wall and membrane deterioration [ 34 – 36 ]. The chemical composition and its variations can be influenced by several factors, such as varieties, agroclimatic conditions, stage of maturity, the part where the EO is derived, and distillation conditions . Section title: 3.1. Chemical Constituents of EOs Educational score: 4.1266374588012695 Domain: biomedical Document type: Study Language: en The presence of 18 compounds was identified from clove oil, which covers 98.64% of the total EO composition ( Table 1 ). Eugenol (70.12%) was identified as a major constituent, followed by trans- β -caryophyllene (12.56%) and eugenol acetate (11.32%). Similarly, other studies revealed that eugenol is the prime component in clove oil [ 39 – 41 ] and is used in food, medical, cosmetics, and agricultural industries as an antioxidant, antimicrobial, antiviral, and antifungal agent . The amount of eugenol in the EO can be directly related to the different geographic regions where the plant has grown, influencing biotic and abiotic factors such as seasonality, developmental stage, plant age, and climatic conditions . In addition, the extraction method of EO can also influence the content of its volatile compounds , these differences in chemical composition can be directly related to pharmacological properties . Section title: 3.1. Chemical Constituents of EOs Educational score: 4.166740417480469 Domain: biomedical Document type: Study Language: en GC–MS results reveal that 12 components in eucalyptus EO are identified, accounting for 99.54% of the total EO composition ( Table 2 ), which mainly consisted of oxygenated and nonoxygenated monoterpenes as well as oxygenated sesquiterpenes. Of these, 1,8-cineole, also named as eucalyptol (52.95%) and terpinen-4-ol (2.63%) were the main oxygenated monoterpenes, while α -pinene (20.75%), p-Cymene (10.10%), and β -myrcene (8.70%) were the main nonoxygenated monoterpenes. These results are similar to EOs obtained from Tanzania, Iran, and Tunisia [ 47 – 49 ]. Most of these compounds are commercially used in the food, pharmaceutical, agricultural, and chemical industries as flavourants, drugs, pesticides, and industrial feedstocks. Particularly, eucalyptol is used in flavourings, fragrances, and cosmetics due to its pleasant aroma and taste. It is also the main ingredient in mouthwashs, cough suppressants, insecticides, and insect repellents . In earlier studies, Tyagi and Malik and Kumar et al. reported 45.4% and 33.6% of eucalyptol, respectively, from eucalyptus EOs from India, which is less than our results. This reveals that the chemical composition of EOs could vary within India, due to the different geographic regions, which can influence the EO composition. Section title: 3.1. Chemical Constituents of EOs Educational score: 4.113743782043457 Domain: biomedical Document type: Study Language: en In garlic oil, 13 compounds were detected in GC–MS analysis, covering more than 96.15% of the total EO composition ( Table 2 ). The chemical composition showed that allyl polysulfides and terpenes, such as diallyl disulfide (22.18%), diallyl trisulfide (43.25%), allyl methyl trisulfide (9.32%), and 2-vinyl-4H-1,3-dithiine (4.80%), were the most predominant components, and the similar result was observed by Herrera-Calderon et al. . Most of these components are responsible for the characteristics of odour and flavour, antioxidant , antimicrobial , antifungal , anti-inflammatory , and antiobesity properties . Section title: 3.2.1. DPPH Radical Scavenging Assay Educational score: 4.206381797790527 Domain: biomedical Document type: Study Language: en DPPH values of EOs with different concentrations showed a significant difference ( p < 0.05) ( Table 3 ). The inhibition percentage has gradually increased with the increasing concentration of EOs. Based on the results, it can be inferred that eucalyptus EO showed maximum antioxidant activity (93.36 ± 0.30%) followed by ginger (87.52 ± 2.84%) and garlic (67.14 ± 1.21%) at 100% concentration. At the same time, the clove EO showed 70.84 ± 3.95% inhibition even at a 5% level, which showed the predominant radical scavenging activity at lower concentrations than the other EOs. The chemical composition ( Table 1 ) displayed the high contribution of eugenol (70.12%), indicating that the total antioxidant activity of the polyphenol mixture is a reflex of the individual components' activity . It allows hydrogen atom donation, stabilizes the phenoxyl radical generation, and creates stable compounds. Generally, eugenol reduces two or more DPPH radicals despite having only one hydrogen atom in the hydroxyl group. Further development of dehydrodieugenol (dimers) with two phenolic hydroxyl groups originating from eugenol intermediate radicals has also been proposed as a mechanism between eugenol and DPPH radicals . Similarly, the level of antioxidant activity of other EOs, including eucalyptus, ginger, and garlic, are influenced by their principal constituents such as 1,8-cineole , α -zingiberene , and diallyl trisulfide , respectively. These compounds are responsible for stabilizing the free radicals by transferring hydrogen atoms or electrons, which can prevent the oxidation process . Section title: 3.2.2. FRAP Assay Educational score: 4.16097354888916 Domain: biomedical Document type: Study Language: en The reducing power of EOs from ferric iron (Fe 3+ ) to ferrous iron (Fe 2+ ) was measured using the FRAP method, and the results are listed in Table 3 . Among the EOs, ginger possesses maximum reducing potential (561.87 ± 8.13 μ mol Fe (II) g −1 ) followed by garlic (155.45 ± 1.12 μ mol Fe (II) g −1 ) and eucalyptus (87.62 ± 2.71 μ mol Fe (II) g −1 ) at 100%, whereas clove EO demonstrated powerful reducing ability (142.29 ± 1.05 μ mol Fe (II) g −1 ) even at a 5% level, surpassing the 100% eucalyptus EO. This evidence shows that the electron-donating properties of clove EO neutralize free radicals and form a stable product. Similarly, other research studies revealed that eugenol and other phenolic components are the predominant components in clove EO, responsible for its potential antioxidant properties . Section title: 3.2.3. TPC Educational score: 4.182740211486816 Domain: biomedical Document type: Study Language: en Phenolic compounds generally have a positive correlation with antioxidant activities due to their electron-donating capability during free radical reactions, and results have shown an increasing trend with increasing concentrations ( p < 0.05) ( Table 3 ). The results indicated that clove EO contains high TPC (375.91 ± 14.21 mg/100 g) at a 5% level, directly correlated with high antioxidant activities. Other EOs showed less TPC than clove EO, even at 25% concentration. Among the other EOs, ginger showed high TPC (124.66 ± 6.03 mg/100 g), followed by garlic (102.33 ± 5.39 mg/100 g), and eucalyptus EO had the least TPC (19.41 ± 12.99 mg/100 g). Generally, TPC may be attributable to intrinsic and extrinsic factors, such as cultivars, soil types and growing conditions, maturity state, and harvesting conditions . The results revealed that the TPC of EOs is directly correlated with antioxidative properties, which may help the cells protect against the oxidative damage produced by free radicals . Moreover, these phenolic compounds are responsible for the defense mechanisms of EOs against microbial attack or environmental stress . Section title: 3.3.1. Agar Well Diffusion Assay Educational score: 4.3196120262146 Domain: biomedical Document type: Study Language: en It is used to study the antimicrobial properties of eucalyptus, clove, garlic, and ginger EOs against foodborne and fishborn bacteria . Ginger EO displayed antibacterial activity against Gram-positive bacteria such as S. aureus (10.33 ± 0.57 mm), MRSA (12.33 ± 0.57 mm), and B. cere us (10.33 ± 0.57 mm). Still, it failed to inhibit the Gram-negative bacterial growth, possibly due to the thick outer lipopolysaccharide layer of Gram-negative bacteria structure, which provides additional protection against ginger antibacterial compounds and reduces the ginger EO activity . In contrast, Gram-positive bacteria have a monopetide layer , which may be easily ruptured by the ginger EO. Garlic EO exhibited the maximum zone of inhibition against both Gram-positive ( S. aureus , 48.33 ± 0.57 mm) and negative bacteria ( V. cholerae , 49.16 ± 0.28 mm). However, it showed no inhibition zone against S. typhi and E. coli . Organosulfur compounds such as allicin and other aliphatic sulfides are responsible for the antimicrobial properties of garlic oil . These compounds protect the gut microbiome and prevent food poisoning . Similarly, eucalyptus EO indicated the highest inhibition zone against Gram-positive bacteria S. aureus (44.66 ± 0.57 mm) followed by Gram-negative bacteria V. cholerae (40.16 ± 0.28 mm). However, it did not exhibit antimicrobial activity against P. aeruginosa . This result agrees with a previous study , where the EO of eucalyptus showed better antimicrobial properties against gram-positive bacteria than gram-negative bacteria. The antimicrobial properties of eucalyptus EO have been due to their prime compounds, such as 1,8-cineole, α -pinene, p-Cymene, and β -myrcene , which affect the fatty acids in the bacterial cell membrane and cytoplasm, as well as proteins, ATP, cell morphology, and antiquorum sensing activities . Section title: 3.3.1. Agar Well Diffusion Assay Educational score: 4.319210052490234 Domain: biomedical Document type: Study Language: en Moreover, clove EO exhibited a zone of inhibition against all the tested microorganisms. It showed the highest zone of inhibition against Gram-negative bacteria V. cholerae (42.16 ± 0.28 mm), followed by Gram-positive bacteria, MRSA (41.33 ± 0.57 mm). Several researchers have found clove effective against gram-positive and negative microorganisms [ 79 – 82 ]. Among the EOs, clove EO demonstrated the highest zone of inhibition against MRSA in the agar well diffusion method, revealing the potential antimicrobial effect against multidrug resistance organisms. In the present study, the higher concentration of eugenol, eugenyl acetate, and other phenolic compounds in clove EO is a significant attribute of its antimicrobial activity . These compounds can denature proteins and change the cell permeability by reacting with cell membrane phospholipids, which cause the inhibition of both Gram-negative and Gram-positive bacteria growth . Based on the antibacterial activity, the hierarchy of the oils' has been observed as follows: garlic > eucalyptus > clove > ginger EO for the Gram-positive bacteria, garlic > clove > eucalyptus EO for Gram-negative bacteria. Moreover, the antimicrobial activity of EOs has correlated with the diffusion abilities such as diffusion coefficient, zeta potential, and droplet size of EOs through bacterial cell membranes . Similarly, different factors, including microbial cultures, geographical origin, plant part, extraction methods, and harvest period, affect the antimicrobial activity of EOs . Overall, the study demonstrated that EOs, except ginger, demonstrated broad-spectrum antibacterial properties against Gram-positive and Gram-negative bacteria. In particular, clove EO displayed a prominent antimicrobial effect against all the tested pathogens and was proposed as a broad-spectrum antimicrobial agent in pharmaceutical industries or as a biopreservative in the food or cosmetic industries. Section title: 3.3.2. MIC and MBC Method Educational score: 4.257071495056152 Domain: biomedical Document type: Study Language: en The antibacterial effect of EOs was determined using MIC and MBC methods, and the results are given in Table 4 . There was a high correlation between the zone of inhibition and the MIC and MBC results of clove EO, which showed the largest zone of inhibition ( S. aureus , MRSA, and V. cholerae ) and lowest MIC and MBC values, ranging from 0.000089 ± 0.0002 to 2.94 ± 0.90 and 0.00018 ± 0.00005 to 2.94 ± 0.90 mg/mL, respectively. Other EOs showed little correlation between the zone of inhibition and MIC and MBC values, which showed the largest inhibition zone but not the lowest MIC and MBC values compared to clove EO. Eucalyptus EO showed the MIC and MBC values ranged from 1.33 ± 0.40 to 85.50 ± 0.80 and 5.34 ± 1.70 to 85.50 ± 0.80 mg/mL, respectively. Garlic oil displayed MIC and MBC values ranging from 0.005 ± 0.001 to 515.70 ± 0.00 and 5.14 ± 1.70 to 386.70 ± 12.80 mg/mL, respectively but did not show antimicrobial activity against E. coli . Similarly, ginger oil exhibited MIC and MBC values ranging from 5.34 ± 1.70 to 439.15 ± 0.00 mg/mL and 5.34 ± 1.70 to 439.15 ± 0.00 mg/mL, respectively, and did not show microbial resistance against salmonella and E. coli . A similar range was confirmed in another study against S. aureus , B. subtilis , E. coli , and Penicillium spp. . This could be due to the EOs' relatively more water-soluble components that can diffuse further through the agar during overnight incubation. The lack of correlation between the results of EOs from the two assays suggests that the two methods are not necessarily comparable. The agar well diffusion method has been regarded as problematic for the antimicrobial testing of natural products, qualitatively, and useful for screening purposes only. Quantitative testing can be conducted using the broth microdilution method to study the antimicrobial activity . Based on the MIC values, the hierarchy has been made for the EOs, that is, clove oil > eucalyptus oil > garlic > ginger (based on lower MIC value). In particular, clove oil demonstrated potent antibacterial activity against all the tested microorganisms. Also, it exhibited the maximum MIC and MBC values against MRSA, which indicates the antimicrobial potential against multidrug-resistant bacteria. Section title: 4. Conclusion Educational score: 4.122579097747803 Domain: biomedical Document type: Study Language: en The current study demonstrated different EOs' antioxidant and antimicrobial properties and could be a potential natural antioxidant and antimicrobial source to replace the synthetic compounds. Regarding antimicrobial activities, eucalyptus, clove, and garlic EOs demonstrated their antimicrobial properties against gram-positive and gram-negative bacteria and could be used as natural preservatives to delay the bacterial spoilage of various food products. Among them, clove EO exhibited better antimicrobial activity against all the tested microorganisms, mainly showing a maximum zone of inhibition against MRSA, which reveals the potential against multidrug-resistant bacteria and makes these oils a possible alternative to synthetic antibiotics. Similarly, based on the antioxidant assay, clove oil possesses a high antioxidant capacity with the least concentration and can readily be used as a natural preservative to delay the oxidation process, maintain nutritional quality, and prolong the food product's shelf life. Further comprehensive research should be conducted to understand the underlying mechanism behind these major components' antioxidant and antimicrobial properties in EOs. | Review | biomedical | en | 0.999997 |
PMC11698608 | Section title: 1. Introduction Educational score: 3.970963716506958 Domain: biomedical Document type: Other Language: en Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) has become the standard of care for patients with primary peritoneal cancers and peritoneal metastasis from gastrointestinal and ovarian carcinomas . The procedure involves the removal of intraperitoneal tumor masses, which may include the excision of affected organs and, in some cases, stripping of the diaphragm. During the HIPEC phase, chemotherapeutic agents heated to temperatures between 41°C and 43°C are instilled into the abdominal cavity to enhance the cytotoxic effects of the chemotherapy . Section title: 1. Introduction Educational score: 4.09141206741333 Domain: biomedical Document type: Other Language: en The Peritoneal Carcinomatosis Index (PCI) is a scoring system used to assess tumor burden in patients with peritoneal metastasis. It ranges from 0 to 39, based on the extent and distribution of the tumor in 13 abdominal regions, with each region assigned a score of 0 (no visible tumor), 1 (tumor less than 0.5 cm), 2 (tumor between 0.5 and 5 cm), and 3 (tumor larger than 5 cm) . The PCI score is a crucial prognostic tool, as higher values correlate with more extensive disease and are associated with longer surgeries, increased blood loss, and significant fluid shifts. These factors contribute to significant hemodynamic instability, posing a challenge to perioperative management and leading to an elevated risk of postoperative morbidity and mortality. Section title: 1. Introduction Educational score: 4.08353328704834 Domain: biomedical Document type: Study Language: en CRS-HIPEC is known to cause considerable physiological stress. The combination of extensive organ resection and hyperthermic chemotherapy leads to fluid shifts, blood loss, and increased intra-abdominal pressure due to the infusion of 3-4 L of heated carrier solution. This rise in intra-abdominal pressure impairs venous return, reduces cardiac output, and can precipitate hemodynamic instability [ 2 – 6 ]. In addition, hyperthermia increases the risk of end-organ ischemia and renal dysfunction, especially in vulnerable patients. The procedure is associated with significant morbidity (20%–40%) and mortality (1%–5%), largely increased by these physiological challenges [ 2 – 4 ]. Section title: 1. Introduction Educational score: 4.027754783630371 Domain: biomedical Document type: Other Language: en Intraoperative management during CRS-HIPEC requires careful attention to fluid balance and hemodynamic stability. Large volumes of fluid, often ranging from 8 to 12 mL/kg/h, may be necessary to maintain homeostasis due to the significant blood loss and fluid shifts. Hemodynamic monitoring plays a key role in guiding fluid therapy and the use of vasoactive agents to maintain cardiac output and adequate end-organ perfusion. Advanced hemodynamic parameters such as cardiac index (CI), Stroke Volume Index (SVI), and stroke volume variation (SVV) are essential for monitoring cardiovascular function and ensuring stable hemodynamics during surgery. Section title: 1. Introduction Educational score: 3.938225030899048 Domain: biomedical Document type: Other Language: en Given the complexity of CRS-HIPEC, the PCI score is a crucial factor influencing intraoperative hemodynamic management. Higher PCI scores often correlate with more severe intraoperative hemodynamic fluctuations, increased need for fluid resuscitation, and advanced hemodynamic monitoring to optimize patient outcomes. Despite its potential therapeutic benefits, the physiological stress induced by CRS-HIPEC necessitates careful perioperative management to reduce the risk of postoperative complications and mortality . Section title: 1. Introduction Educational score: 4.0973615646362305 Domain: biomedical Document type: Study Language: en This study aims to evaluate the relationship between tumor burden, perioperative hemodynamic management, fluid therapy, and postoperative outcomes in patients undergoing CRS-HIPEC. We hypothesize that effective hemodynamic management during and after the procedure is associated with improved outcomes, including a reduction in complications, shorter hospital stays, and lower postoperative morbidity and mortality. Section title: 2. Methodology Educational score: 4.044240951538086 Domain: biomedical Document type: Study Language: en This prospective observational study was conducted from April 2016 to December 2022 after approval from Institutional Ethics Committee (IEC). The inclusion criteria for the study were primary peritoneal cancers, gastrointestinal and gynecological cancer patients posted for CRS-HIPEC, aged between 18 and 70 years, and belonging to the American Society of Anesthesiologists physical status class I–III. Waiver of consent was granted by IEC in view of the observational nature of the study. Patients in whom HIPEC was canceled after CRS because of change in surgical plan were excluded from the study. The study was conducted as per principles of the Declaration of Helsinki and its subsequent amendments. Section title: 2. Methodology Educational score: 2.504333972930908 Domain: biomedical Document type: Study Language: en In the preoperative period, patients' disease status, medical history, preanesthetic evaluation, laboratory investigations, radiological imaging, and other relevant clinical data were reviewed and recorded. Section title: 2. Methodology Educational score: 3.8678348064422607 Domain: biomedical Document type: Other Language: en In the operating room, standard monitoring included continuous measurement of heart rate, blood pressure, oxygen saturation, and temperature, with documentation in the anesthesia chart. Anesthesia induction was performed using intravenous propofol and fentanyl, along with muscle relaxants such as atracurium or vecuronium, as appropriate. An arterial catheter was placed in all patients for invasive blood pressure monitoring and advanced hemodynamic monitoring. Central venous catheter placement was also performed for administering vasopressors if needed. Section title: 2. Methodology Educational score: 4.00259256362915 Domain: biomedical Document type: Study Language: en Hemodynamic monitoring was enhanced using the FloTrac system with the EV1000 monitoring platform (Edwards Lifesciences) connected to the arterial line. Parameters such as CI, cardiac output (CO), stroke volume (SV), SVI, and SVV were recorded and utilized to guide goal-directed fluid therapy (GDFT). The objective of fluid management during the perioperative period was to maintain CI, SVV, SVI, and pulse pressure variation (PPV) within 20% of the baseline values, established after connecting the FloTrac system. Section title: 2. Methodology Educational score: 4.009646415710449 Domain: biomedical Document type: Other Language: en The main objective of anesthesia management during CRS-HIPEC included a balanced anesthetic technique to ensure optimal hemodynamic stability, oxygenation, and normothermia. The FloTrac system with the EV1000 platform was used as a key tool for hemodynamic monitoring, providing real-time measurements of dynamic parameters such as CI and SVI. This allowed precise adjustments in fluid administration and vasopressors. The anesthesia team adhered to GDFT protocols, which emphasized maintaining parameters within a 20% range to reduce intraoperative hypotension and maintain organ perfusion. The use of low dose norepinephrine (often referred to as “baby norepinephrine”), was adjusted as needed to support hemodynamic goals. Section title: 2. Methodology Educational score: 4.090195655822754 Domain: biomedical Document type: Study Language: en Data on patient characteristics, anesthetic management, intraoperative fluid and blood transfusion, coagulation management, body temperature, and delta temperature (defined as the difference between maximum and minimum temperatures measured throughout the CRS-HIPEC procedure), as well as arterial and venous blood gas measurements, were collected. At the conclusion of the procedure, the PCI score, the number of organs resected, the number of anastomoses performed, diaphragmatic stripping (if performed), the completeness of cytoreduction (CC) score—where CC-0 indicates no visible residual tumor, CC-1 indicates residual tumors up to 2.5 mm, CC-2 indicates residual tumors between 2.5 mm and 2.5 cm, and CC-3 indicates residual tumors larger than 2.5 cm, and the chemotherapeutic agent(s) administered during HIPEC were documented. The duration of each phase of the surgery, along with the total surgical time, was also recorded. The HIPEC protocol involves the use of mitomycin-C (15 mg/m 2 of body surface area [BSA]) and doxorubicin (15 mg/m 2 of BSA) for pseudomyxoma peritonei, mesothelioma, colorectal, and appendiceal cancers. For gastric and ovarian cancers, cisplatin (75 mg/m 2 of BSA) is used. HIPEC is performed for 90 min using the open “Coliseum” technique, with peritoneal dialysis solution (3 L) serving as the carrier solution. Sodium thiosulfate was not used in any of the patients due to its unavailability. Section title: 2. Methodology Educational score: 3.8792483806610107 Domain: biomedical Document type: Other Language: en Temperature control during CRS was managed using fluid warmers and warming blankets to maintain normothermia. During the HIPEC phase, warming devices were discontinued, and cold fluids along with cool air blankets were used to keep the core body temperature below 39°C. In the postoperative period, if a patient developed hypothermia, fluid warmers and warming devices were used as needed to restore and maintain normothermia. Section title: 2. Methodology Educational score: 3.90910005569458 Domain: biomedical Document type: Study Language: en The postoperative course, including complications classified according to the Clavien–Dindo (CD) classification ( Table 1 ), was tracked. The postoperative intensive care unit (ICU) stay and morbidity were assessed using the Sequential Organ Failure Assessment (SOFA) score ( Table 2 ). In addition, the length of stay in both the ICU and hospital, as well as 30- and 90-day mortality, were recorded. Section title: 2. Methodology Educational score: 4.101911544799805 Domain: biomedical Document type: Study Language: en We classified patients based on their PCI score into three groups: PCI < 10, PCI 11–20, and PCI > 20, representing the extent of disease. This classification was used to assess intraoperative hemodynamics, fluid therapy, and perioperative outcomes. The primary outcome of this study was to evaluate the impact of PCI scores on hemodynamic monitoring parameters, including CI, CO, SVI, delta SVI, PPV, SVV, and fluid management. Secondary outcomes included postoperative complications according to the CD classification, 30- and 90-day mortality, and the length of ICU and hospital stay. Section title: 2.1. Statistical Analysis Educational score: 4.078200340270996 Domain: biomedical Document type: Study Language: en Demographic, clinical, and disease-related variables were presented as frequencies (percentages), means (standard deviations), or medians (interquartile ranges), as appropriate. Parametric or nonparametric statistical tests were used based on the distribution of the data (normally distributed or not). The Kolmogorov–Smirnov test was used to assess the normality of baseline characteristics among patients classified into different PCI groups. For non-normally distributed data, the Mann–Whitney U test and Kruskal–Wallis test were employed, while ANOVA was applied for normally distributed data to evaluate associations among various perioperative parameters and related outcomes. Fisher's exact test was used to compare expected and observed outcomes and to assess associations between categorical variables. Univariable and multivariable logistic regression analyses were performed to identify significant associations between perioperative parameters and postoperative outcomes. A p value of less than 0.05 was considered statistically significant. Section title: 3. Results Educational score: 3.7745039463043213 Domain: biomedical Document type: Study Language: en A total of 203 patients underwent CRS-HIPEC during the study period. The age, gender, primary malignancies, and duration of surgery for different PCI groups are detailed in Table 1 . Information on chemotherapeutic drugs used, total fluid administered, blood transfusions, CC score, number of organs resected, number of anastomoses, delta-temperature, complications, and duration of hospital stay are provided in Table 2 . Section title: 3. Results Educational score: 4.093160629272461 Domain: biomedical Document type: Study Language: en Patients with a greater burden of disease who underwent extensive resections (PCI > 20) had a significantly longer mean duration of surgery (796.2 ± 158.3 min) compared with those with a PCI between 0 and 10 (551 ± 127 min) and a PCI between 11 and 20 (661.78 ± 137.7 min) ( p ≤ 0.01) ( Table 3 ). Section title: 3. Results Educational score: 4.087660789489746 Domain: biomedical Document type: Study Language: en The mean volume of fluids administered, excluding blood and blood products, in different PCI groups is detailed in Table 3 . The volume of intraoperative fluids administered was found to be statistically significant across all three PCI score-based patient groups (Pearson's Chi-square: 48.315; p ≤ 0.01) ( Table 3 ). The correlation between IV fluid given during CRS and various perioperative parameters are mentioned in Appendix table 2 . Section title: 3. Results Educational score: 3.987354278564453 Domain: biomedical Document type: Study Language: en Baseline mean CI values were significantly different among patients with PCI scores of 0–10 , 11–20 , and > 20 (ANOVA: sum of squares: 79.028; p ≤ 0.01). Section title: 3. Results Educational score: 4.127644062042236 Domain: biomedical Document type: Study Language: en The mean SVI values were significantly different at 10 and 60 min after starting HIPEC in patients with PCI scores of 0–10 (SVI-10 min: 48.29; SVI-60 min: 47.97), 11–20 (SVI-10 min: 41; SVI-60 min: 42.11), and > 20 (SVI-10 min: 39.5; SVI-60 min: 39.48) (ANOVA: SVI CRS beginning: sum of squares: 16,493.679, p =0.002; HIPEC 10 min: sum of squares: 28,393.892, p ≤ 0.01; SVI HIPEC 60 min: Sum of squares: 25,613.411, p ≤ 0.01) . Section title: 3. Results Educational score: 3.981482982635498 Domain: biomedical Document type: Study Language: en Baseline mean CI values were significantly different among patients with PCI scores of 0–10 , 11–20 , and > 20 (ANOVA: sum of squares: 79.028; p ≤ 0.01). However, these differences were not observed in mean CI values during the intraoperative or postoperative periods . Section title: 3. Results Educational score: 3.482637405395508 Domain: biomedical Document type: Study Language: en Mean SVV values were significantly different 60 min after starting HIPEC in patients with PCI scores of 0–10 , 11–20 , and > 20 . However, there were no statistically significant differences in SVV trends during the CRS or postoperative periods . Section title: 3. Results Educational score: 4.116260528564453 Domain: biomedical Document type: Study Language: en We found that the mean body temperature did not significantly change during CRS from the initial temperature. However, body temperature decreased by about 0.6°C–0.8°C 10 min after commencing HIPEC, followed by an increase of 1.3°C–1.4°C during HIPEC, compared with the beginning of CRS. There was no significant difference in mean temperature at any corresponding time point based on PCI scores during the perioperative period (Appendix Table 1 ). The mean temperature after patients' arrival to the ICU was 35.6°C (SD: 1.91). Of the 203 patients we studied, 145 patients had a recorded temperature on shifting to the ICU. Of these, 44 patients (30.3%) were hypothermic (< 35°C core body temperature) on arrival to the ICU. Section title: 3. Results Educational score: 4.062930107116699 Domain: biomedical Document type: Study Language: en Primary diagnosis (disease), the number of organs resected during CRS, and the number of anastomoses done were analyzed for their impact on postoperative complications. Primary diseases significantly affected postoperative complications ( p ≤ 0.01), while the number of organs resected ( p =0.258) and anastomoses done (0.431) did not affect the postoperative complications ( Table 4 ). Section title: 3. Results Educational score: 4.025127410888672 Domain: biomedical Document type: Study Language: en Interestingly, diaphragmatic stripping did not independently increase ICU stay length or in the regression model. However, diaphragmatic stripping was significantly associated with the need for mechanical ventilation for 24 h or more . Total blood loss, need for mechanical ventilation for 24 h or more, duration of surgery, CC score after CRS, blood loss during CRS, total number of PRBCs transfused during the procedure, and PCI score were highly significant on univariable logistic regression. Section title: 3. Results Educational score: 4.109838008880615 Domain: biomedical Document type: Study Language: en Renal function was assessed using serum creatinine values. The mean (SD) of creatinine levels on postoperative days (PODs) 1, 3, and 5 were recorded ( Table 3 ). On POD 1, two patients had serum creatinine levels greater than 1.5 mg/dL (2.06 and 1.60 mg/dL), and in both patients, serum creatinine levels normalized by POD 3. On POD 3, one patient had a serum creatinine level of 1.80 mg/dL, which increased to 3.00 mg/dL by POD 5, and this patient required renal replacement therapy. Another patient had a serum creatinine level of 1.5 mg/dL on POD 3, which normalized by POD 5. These differences between the various PCI groups were statistically significant on POD 3 ( p ≤ 0.01). Section title: 3. Results Educational score: 4.084374904632568 Domain: biomedical Document type: Study Language: en The median duration of ICU stay varied across patients with different PCI scores. Patients with PCI > 20 had a median ICU stay of 4 days (IQR: 3–7 days), compared with 3 days (IQR: 2–3 days) for those with PCI scores between 0–10 and 3 days (IQR: 2–4 days) for those with PCI scores between 10 and 20. (Kruskal–Wallis H = 22.495; p ≤ 0.01). Section title: 3. Results Educational score: 4.039315223693848 Domain: biomedical Document type: Study Language: en The 30-day survival rates were 99.1% for patients with PCI 0–10, 95.5% for those with PCI 11%–20%, and 93.3% for those with PCI > 20. While this difference is clinically significant, it was not statistically significant (Pearson's Chi-square: 2.354; p =0.308). Section title: 3. Results Educational score: 3.851152181625366 Domain: biomedical Document type: Study Language: en The 30-day readmission rates were comparable across all PCI groups (Pearson's Chi-square: 0.849; p =0.654) ( Table 3 ). Section title: 3. Results Educational score: 4.09058952331543 Domain: biomedical Document type: Study Language: en We analyzed the effect of these seven parameters viz., total blood loss, need for mechanical ventilation for 24 h or more, duration of surgery, CC score, blood loss during CRS, total number of PRBCs transfused during the procedure, and PCI score on ICU stay length using multivariate logistic regression and found that mechanical ventilation for 24 h or more and CC score at the end of CRS predicted an ICU stay longer than 8 days (reference outcome: ICU stay of up to 7 days) ( Table 5 ). Section title: 3. Results Educational score: 4.090755462646484 Domain: biomedical Document type: Study Language: en On univariable logistic regression, SVI at 60 min after starting HIPEC, ICU stay longer than 7 days, and readmission within 30 days of surgery significantly predicted 30-day survival. However, ICU stay longer than 7 days and maximum SVV during HIPEC phase were predictive of 30-day survival on multivariable logistic regression ( Table 6 ). Section title: 3. Results Educational score: 4.037132263183594 Domain: biomedical Document type: Study Language: en On multivariable analysis, average heart rate and average CO during CRS and end-tidal carbon dioxide during reconstructive phase were predictive of postoperative complications after CRS-HIPEC ( Table 7 ). Section title: 3. Results Educational score: 3.685455799102783 Domain: biomedical Document type: Study Language: en A total of 21 out of 203 patients (10.34%) were readmitted within 30 days after surgery. The reasons for readmission included sepsis (3/21; 14.28%), electrolyte imbalances such as hyperkalemia (3/21; 14.28%), medical conditions (e.g., dengue fever and acute exacerbation of asthma) (3/21; 14.28%) patients, intestinal obstruction (2/21; 9.52%), nutritional support (1/21; 4.76%), further management of residual disease (2/21; 9.52%), perforation peritonitis (1/21; 4.76%), anastomotic leaks (2/21; 9.52%), and short bowel syndrome (1/21; 4.76%). In 3 patients, the reason for readmission was not found on record (14.28%). Section title: 3. Results Educational score: 2.898362874984741 Domain: clinical Document type: Clinical case Language: en Of the 203 patients operated, 7 patients died in hospital. One patient had cardiac arrest after hemodialysis for hyperkalemia after undergoing re-exploration surgery for anastomotic leak. Six patients had severe sepsis and septic shock with multi organ dysfunction syndrome and died. Section title: 4. Discussion Educational score: 3.7768845558166504 Domain: biomedical Document type: Study Language: en This study focuses on highlighting major perioperative concerns in CRS-HIPEC, including duration of surgery, blood loss, delta temperature, PCI, and fluid management. To the best of our knowledge, this is one of the largest cohorts studied for hemodynamic parameters in CRS-HIPEC. Section title: 4. Discussion Educational score: 3.960125207901001 Domain: biomedical Document type: Study Language: en Large fluid shifts are common during cytoreduction, and intraoperative fluid losses can reach up to 8–12 mL/kg and require adequate crystalloids and colloids to ensure adequate perfusion pressure and urine output without causing fluid overload . Patients with lower cardiopulmonary reserve may not tolerate high volumes of intravenous fluids and may need vasopressors/inotropes based on the extent of their ability to tolerate fluids, as also their fluid responsiveness. Liberal fluid strategy, with fluid as high as 1500 mL/h given to patients described in some studies, has been shown to cause several complications, including fluid overload, surgical site edema, end organ dysfunction, and greater length of ICU and hospital stay [ 11 – 15 ]. Section title: 4. Discussion Educational score: 4.104353904724121 Domain: biomedical Document type: Study Language: en Conversely, restrictive fluid strategies may compromise end-organ perfusion, particularly during the hemodynamic fluctuations during CRS-HIPEC, leading to renal dysfunction reported in few studies . However, a retrospective study has showed that restrictive fluid strategy decreased the length of hospital stay (11.5 vs. 9.7 days; p ≤ 0.01) and 60-day postoperative complications (28% vs. 45%; p =0.02), with incidence of postoperative renal dysfunction and the highest serum creatinine levels not significantly different in the restrictive versus permissive fluid therapy groups . CRS-HIPEC procedure is known to cause acute kidney injury (AKI) in the postoperative period, and apart from the decreased renal perfusion, use of cisplatin chemotherapy alone or in combination is an important cause of AKI . Section title: 4. Discussion Educational score: 3.657299757003784 Domain: biomedical Document type: Other Language: en GDFT approach which involve fluid administration based on CI, SVI, or SVV is well-suited for CRS-HIPEC, where physiological challenges of major surgery and fluid shifts, and hyperthermic environment leads to difficulty in maintaining hemodynamic stability and adequate tissue oxygenation . Section title: 4. Discussion Educational score: 4.128794193267822 Domain: biomedical Document type: Study Language: en In our study, fluid administration in patients with three different PCI groups showed a highly significant difference ( p ≤ 0.01), suggesting that patients with higher PCI scores need aggressive fluid management. In addition, significant variations were observed in the mean CI and mean SVI at various stages of the CRS-HIPEC, particularly at the beginning of CRS and during HIPEC, which indicates the impact of PCI on cardiac function. Mean SVV at 60 min of HIPEC phase also showed significant difference ( p ≤ 0.01), highlighting the hemodynamic instability in patients with higher PCI scores. The use of FloTrac system with the EV1000 platform ensured optimal hemodynamic stability and organ perfusion during the procedure. While some groups focus on the duration of mean arterial pressure (MAP) below 60 mmHg, our protocol prioritized maintaining hemodynamic parameters within the defined range to minimize hypotensive episodes. Emerging technologies, such as machine learning-based early warning systems (e.g., HYPE Randomized Clinical Trial) and predictive models for intraoperative hypotension (e.g., Hypotension Prediction Index (HPI)) were shown to have good clinical outcomes, but their application in our study was not implemented except for 4 cases where we used HPI in addition to the FloTrac . Section title: 4. Discussion Educational score: 3.6498734951019287 Domain: biomedical Document type: Other Language: en As per the international expert consensus, the PCI score is crucial in decision-making for CRS-HIPEC. In patients with colorectal cancer, a PCI score ≤ 16 is acceptable for CRS-HIPEC, whereas a PCI scores > 20 may indicate a need for alternative treatments and supportive care . However, optimal PCI score cutoff is not yet determined for some cancers like gastric cancer and pseudomyxoma peritonei . Section title: 4. Discussion Educational score: 4.107018947601318 Domain: biomedical Document type: Study Language: en Esteve-Perez et al. studied 92 adult patients with colorectal and ovarian malignancies undergoing CRS-HIPEC and found significant interindividual variation in the fluid requirement. They also observed that PCI and duration of surgery, fluid therapy, and intraoperative transfusion percentage were highly correlated ( p < 0.02). Similar to these findings, we found that all three of the PCI score-based patient groups showed a statistically significant variation in the volume of intraoperative fluids given. This was found to be clinically relevant, as larger burden of disease necessitates more extensive and technically complex surgical resection, entailing greater blood loss and thus need for more fluids to be administered during surgery. Higher PCI values are a major predictor of postoperative morbidity, especially for scores > 20. Section title: 4. Discussion Educational score: 4.024836540222168 Domain: biomedical Document type: Study Language: en High volume diseases (greater PCI) lead to increased blood loss and higher fluid requirements during CRS-HIPEC . Multivariable analyses from previous studies underscore age, intraoperative fluid rates, and blood loss as independent predictors of postoperative morbidity in CRS-HIPEC . Specifically, higher fluid infusion rates (> 15.7 mL/kg/h) have been associated with increased comprehensive complication indices and prolonged ICU stays . Section title: 4. Discussion Educational score: 4.080584526062012 Domain: biomedical Document type: Study Language: en On multivariable analysis, we found that higher PCI scores were associated with prolonged mechanical ventilation (> 24 h), increased 30-day hospital readmission rates, and reduced 30-day survival. We also found a positive correlation between total fluid administered and ICU stay, but there was no significant association between total fluid administered and 30-day survival, suggesting that other factors may influence survival outcomes. Section title: 4. Discussion Educational score: 4.042897701263428 Domain: biomedical Document type: Study Language: en The identification of predictors for prolonged ICU stays and 30-day survival enhances risk stratification and prognostication in CRS-HIPEC. The significance of mechanical ventilation for 24 h or more and the CC score underscores their utility as key determinants of postoperative recovery and overall survival, as found in our study. These findings are similar to what were found by Macrì et al. in their retrospective analysis of outcomes of CRS-HIPEC in patients with ovarian malignancy . Section title: 4. Discussion Educational score: 3.4006736278533936 Domain: biomedical Document type: Study Language: en In this study, 30.3% patients had a core body temperature < 35°C on arrival to ICU (rebound hypothermia). The hypothermia in postoperative period may be because of failure to restart the warming devices after completion of HIPEC phase and because of the higher delta temperature. Section title: 4. Discussion Educational score: 4.084804534912109 Domain: biomedical Document type: Study Language: en The emphasis of our study on tailoring patient care based on disease extent (PCI scores) and identified perioperative predictors allows for a more individualized approach to the perioperative care of patients undergoing CRS-HIPEC. Our findings align with the existing literature on the challenges associated with the perioperative management of CRS-HIPEC. The prolonged duration of surgery in patients with extensive disease corroborates studies highlighting the intricacies of extensive resections and their subsequent impact on procedural timelines. The pattern of hemodynamic parameters observed in this study underscores their critical role in the perioperative management of CRS-HIPEC patients. Section title: 4. Discussion Educational score: 3.2553646564483643 Domain: biomedical Document type: Study Language: en Our study has certain limitations. First, as a single-center study, the generalizability of the findings to different geographical and healthcare settings is limited. Second, variations in clinical practices, surgical techniques, and postoperative care protocols may lead to differences in outcomes. In addition, our study lacked a predefined sample size, as we enrolled consecutive CRS-HIPEC patients. Section title: 5. Conclusion Educational score: 4.044522285461426 Domain: biomedical Document type: Study Language: en Our study highlights significant variations in CI, SVI, and fluid requirements across different PCI groups. A higher PCI score is significantly associated with increased duration of surgery, fluid requirements, the necessity for invasive hemodynamic monitoring, postoperative complications, and ICU stay. Tailoring perioperative strategies based on PCI scores has the potential to optimize these outcomes. | Other | biomedical | en | 0.999997 |
PMC11698610 | Section title: 1. Introduction Educational score: 4.076336860656738 Domain: biomedical Document type: Study Language: en Linell and Norden first described Mycobacterium marinum in humans in 1954. The mycobacteria were isolated from the skin lesions of swimmers who had bathed in a contaminated pool . M. marinum can infect many fish species, leading to contamination of water and fish products . Inoculation to humans occurs through injured skin, resulting in the formation of a solitary nodule known as the “fish tank granuloma” . The bacteria can spread via the lymphatics, in a sporotrichoid-like fashion, leading to further verrucous plaques and nodules, typically involving the hands . Disseminated infection has been reported in the immunocompromised and can present with extracutaneous manifestations such as arthritis and osteomyelitis . Section title: 1.1. Case Presentation Educational score: 3.375786542892456 Domain: clinical Document type: Clinical case Language: en A 63-year-old Caucasian woman presented with a 6-week history of low-grade fever and widespread pustules that were resistant to treatment with flucloxacillin. Bacterial and viral swabs were performed and found to be negative. Blood tests showed mildly raised inflammatory markers but were otherwise unremarkable. The patient had a history of rheumatoid arthritis and bronchiectasis. Her medications included long-term methotrexate and intermittent courses of prednisolone. Section title: 1.1. Case Presentation Educational score: 1.756631851196289 Domain: clinical Document type: Clinical case Language: en On examination, she was found to have multiple scattered plaques, pustules, erosions, and necrotic wounds in a widespread distribution. Section title: 1.1. Case Presentation Educational score: 3.6215391159057617 Domain: clinical Document type: Clinical case Language: en A skin biopsy was performed and was found to exhibit numerous pustules and intraepidermal neutrophils. The entire dermis and superficial subcutis showed heavy neutrophilic infiltration and necrotic debris within an apparent abscess. A diagnosis of a pustular variant of Sweet's syndrome was considered and treatment with prednisolone was commenced with some initial improvement of the symptoms. Section title: 1.1. Case Presentation Educational score: 2.1417462825775146 Domain: clinical Document type: Clinical case Language: en Four months later the patient was admitted to hospital due to a worsening eruption with increasing pustules, necrotic areas, and erythematous plaques , as well as joint pains and neutropenic sepsis. Section title: 1.1. Case Presentation Educational score: 2.043954610824585 Domain: clinical Document type: Clinical case Language: en A repeat skin biopsy was performed that confirmed the previous findings and did not show any new features. The patient's condition did not improve following an increased dose of prednisolone, and treatment with Dapsone was therefore also commenced. Section title: 1.1. Case Presentation Educational score: 3.705474615097046 Domain: biomedical Document type: Clinical case Language: en Despite that, the patient continued to deteriorate, and a third skin biopsy was performed. This time, histological examination demonstrated a necrotic abscess with deep dermal neutrophilic infiltration . The amount of infiltration and degree of fatty involvement was beyond that expected for Sweet's syndrome. Ziehl-Neelsen (ZN) staining was performed which revealed abundant atypical acid-fast bacilli (AFB). Section title: 1.1. Case Presentation Educational score: 2.741389513015747 Domain: biomedical Document type: Clinical case Language: en ZN staining of earlier biopsies was performed retrospectively that also confirmed the presence of AFB. A fourth biopsy was undertaken for tissue culture, which isolated Mycobacterium marinum . Based on this information, the diagnosis was revised to disseminated M. marinum infection. Section title: 1.1. Case Presentation Educational score: 1.3660012483596802 Domain: clinical Document type: Clinical case Language: en Following close questioning, the patient denied any contact with obvious aquatic sources of infection. She did, however, admit to having cared for a pet lizard (inland bearded dragon, Pogona vitticeps ) that had died from an unknown illness shortly before the patient's diagnosis. Section title: 1.1. Case Presentation Educational score: 1.601556658744812 Domain: clinical Document type: Clinical case Language: en The patient received multiple courses of antimycobacterial regimens with eventual resolution, albeit with significant scarring and disfigurement . Section title: 2. Discussion Educational score: 3.896989583969116 Domain: biomedical Document type: Study Language: en Infection with M. marinum follows contact with infected water or via contact with an infected fish tank or shellfish . The two conditions thought to be required for M. marinum infection are thought to be injury or abrasion to the skin and exposure to a contaminated aqueous environment. In one study, almost half (49%) of M. marinum infections were aquarium-related, 27% were related to fish or shellfish injuries, and 9% were related to injuries associated with saltwater or brackish water . Section title: 2. Discussion Educational score: 2.8121395111083984 Domain: biomedical Document type: Clinical case Language: en Disseminated cases are fairly uncommon. A small number of cases of M. marinum infection occurring in patients with HIV and in patients treated with tumor necrosis factor alpha (TNF- α ) inhibitor have been reported . Our patient's history of iatrogenic immunocompromise (regular methotrexate for rheumatoid arthritis, and intermittent prednisolone for bronchiectasis) is the likely culprit for her disseminated disease. Section title: 2. Discussion Educational score: 2.235067129135132 Domain: biomedical Document type: Other Language: en The inland bearded dragon is the most popular pet lizard in the United Kingdom and United States . Systemic infection with M. marinum in an inland bearded dragon has been reported following the lizard's ingestion of infected guppies . Other reptiles reported to be infected with M. marinum include the royal python (Python regius) , crocodilians, and Egyptian spiny-tailed lizards . However, nonaquatic, zoonotic transmission of M. marinum has not been reported to date. Section title: 2. Discussion Educational score: 1.923165202140808 Domain: biomedical Document type: Clinical case Language: en Interestingly, we could not elicit any history of contact between our patient and any aquatic sources of infection. The patient's exposure to an inland bearded dragon that died from an unknown illness near the time of diagnosis raises fascinating questions about the possibility of transmission via a surmised nonaquatic route. Although microbiological studies of the deceased dragon would have helped in testing this hypothesis, the body of the deceased dragon was unfortunately not available for testing. Section title: 2. Discussion Educational score: 4.2002129554748535 Domain: biomedical Document type: Study Language: en The histology of M. marinum infected tissues often reveals the development of noncaseating granulomata from a neutrophilic abscess . Few bacilli can be observed except in the immunocompromised host . The surrounding dermis shows a lymphohistiocytic infiltrate, whilst the overlying epidermis can be ulcerated, parakeratotic, or acanthotic . Overall, features are rather nonspecific with pseudoepitheliomatous hyperplasia accompanied by a poor yield of positive isolates from culture specimens . Section title: 2. Discussion Educational score: 3.728562355041504 Domain: biomedical Document type: Other Language: en We argue that a differential diagnosis of M. marinum infection should be considered in patients with indicative clinical and histological features, especially in the background of immunocompromise, despite the absence of an obvious aquatic source of infection. Awareness of this entity could lead to earlier diagnoses and reduced morbidity and mortality. | Study | biomedical | en | 0.999999 |
PMC11698612 | Section title: 1. Introduction Educational score: 3.9816176891326904 Domain: biomedical Document type: Review Language: en In recent years, the increase in irregular use of antibiotics around the world has become unstoppable. Antibiotics have become commonplace, routinely used in medical practice. Consequently, resistance mechanisms in microorganisms have developed, enhancing their ability to survive by disrupting the action pathways of antibiotics. As a result, antibiotics used to treat many diseases have become insufficient, leading to a search for alternative treatments. Many scientists are now exploring innovative treatment areas and new molecules. Our environment harbors numerous microorganisms, many of which are pathogenic and highly dangerous to human health. These pathogens have developed significant resistance mechanisms against antibiotics, and at this point, antimicrobial peptides (AMPs), potent and naturally and synthetically occurring structures, are emerging as a defense against these detrimental consequences . Section title: 1. Introduction Educational score: 3.939574718475342 Domain: biomedical Document type: Review Language: en AMPs are naturally and synthetically occurring structures that are produced and synthesized by many living organisms, including humans, which act against microbial sources. These structures play a crucial role in the innate immune system, contributing to nonadaptive defense mechanisms against various unsanitary microorganisms. In addition, another advantage of AMPs is that they exhibit broad-spectrum antimicrobial activity. Thus, they could be innovative therapeutic molecules with high effectiveness against many microorganisms [ 3 – 5 ]. Section title: 1. Introduction Educational score: 4.088465213775635 Domain: biomedical Document type: Other Language: en Examples of AMPs found in nature include cathelicidins and defensins. These peptides are produced by mammals. Cathelicidins are positively charged peptides . Their mechanism of action involves direct effects on the cell membrane. Specifically, they interact electrostatically with the cell membrane and create pores, leading to death of the microbe . LL-37, AMP, and cathelicidin derivative is produced in humans. This peptide, which has an α -helical structure, penetrates the cell membrane and directly kills the microorganism by disrupting the cell membrane . Section title: 1. Introduction Educational score: 4.005582809448242 Domain: biomedical Document type: Study Language: en In previous studies by Polat et al. , LL-37-like peptides were designed, their amino acid sequences were synthesized, and their antimicrobial activity and cytotoxicity results were published. These NET peptides were rendered resistant to protease and their activity was tested on different biofilm forming bacteria . Determination of the effect of these designed peptides on macrophages are revealed for the first time in our study. Understanding the role of peptides in the immune system is crucial for the future development of these peptides as new drug molecules. Section title: 2.1. Design of AMPs, Solid-Phase Chemical Synthesis, and High-Performance Liquid Chromatography (HPLC) Analyses Educational score: 4.034913539886475 Domain: biomedical Document type: Study Language: en In the literature, AMPs are generally described as hydrophobic and positively charged . In our previous study, we designed four hydrophobic and positively charged peptides of 10–20 amino acids in length using d- and l-form peptides with a similar structure as LL-37, which we found to be effective against bacterial biofilms . In this study, we examined the effects of these four peptides on macrophages to clarify their effects on the immune system ( Table 1 ). Section title: 2.1. Design of AMPs, Solid-Phase Chemical Synthesis, and High-Performance Liquid Chromatography (HPLC) Analyses Educational score: 4.157854080200195 Domain: biomedical Document type: Study Language: en The peptides were synthesized using a Liberty Blue peptide synthesizer (CEM, Matthews, NC, USA). After the synthesis was complete, the peptides were cleaved from the solid support using a Razor device, as specified in the manufacturer's manual. The synthesized AMP samples were first prepared at a concentration of 2 mg/mL for analysis by reversed-phase HPLC. For HPLC analysis, a C-18 analytical column was used, with Buffer A (dH 2 O + 0.05% TFA) and Buffer B (acetonitrile + 0.025% TFA) as the mobile phases. After equilibrating the column at 5% Buffer B, the peptide was injected and eluted using a gradient protocol (%20–%80 Buffer B). The peptides were run on an analytical HPLC column, and their approximate hydrophobicity was calculated according to the retention times of the chromatographic peaks. Next, the peptides were prepared at a concentration of 10 mg/mL and run on a semipreparative C-18 HPLC column. The purified peptide peaks were collected, and the samples were subsequently lyophilized (freeze-dried). The concentrations of the lyophilized AMP samples were determined using the Pierce Quantitative Fluorometric Peptide Assay kit (Thermo Fisher Scientific, Waltham, MA, USA). Section title: 2.2. Cytotoxicity Assay Educational score: 4.099444389343262 Domain: biomedical Document type: Study Language: en The TIB-71 RAW 264.7 macrophage line, which was obtained from Mus musculus , was used in this study, and this cell line was supplied by ATCC (Manassas, VA, USA). The MTT Cell Proliferation Kit (Sigma–Aldrich, St. Louis, MO, USA), a colorimetric method, was used to evaluate the damage caused by the peptides in eukaryotic cells. TIB-71 RAW 264.7 macrophages were revived under appropriate culture conditions (37°C, 5% CO 2 ) to prepare for the experiment. The final concentration of peptides ranged 0.125–64 μg/mL. Samples were examined in triplicates for each concentration. Cells incubated without peptide treatment under the same conditions were used as the control. Magainin 2 (Mag2), a known natural AMP with no cytotoxic effects, was used as a positive control . The results were obtained using a 96-well plate reader at 550 and 690 nm. Section title: 2.3. Investigation of Tumor Necrosis Factor- α (TNF- α ) Expression by ELISA Educational score: 2.725874423980713 Domain: biomedical Document type: Study Language: en Within the scope of the ELISA study, the effect of varying concentrations of the peptides we synthesized on the mouse macrophage cell line was examined. Section title: 2.3. Investigation of Tumor Necrosis Factor- α (TNF- α ) Expression by ELISA Educational score: 3.9832069873809814 Domain: biomedical Document type: Study Language: en In this study, a cell line that was not treated with AMPs and LPS, a cell line treated only with AMPs, a cell line treated only with LPS, and a cell line treated with both LPS and AMPs were used. To find the changing TNF- α ratio after incubation, the kit named Mouse Tumor Necrosis Factor α ELISA Kit-RAB0477 (Sigma–Aldrich) was applied according to the protocol. Graphpad Prism (9.0.0) was utilized for performing a one-way ANOVA test ( α = 0.05) for the statistical analysis. Section title: 2.4. Investigation of Interferon- γ (IFN- γ) Expression by ELISA Educational score: 3.6873791217803955 Domain: biomedical Document type: Study Language: en Similarly, ELISA was applied to measure the change in IFN- γ levels in response to the peptides and LPS. In this experiment, the Mouse IFN- γ ELISA Kit-E-EL-M0048 was applied according to the specified kit protocol, and the results were evaluated. Section title: 2.5. Interleukin-6 (IL-6) Expression Analysis by Western Blotting Educational score: 4.0688886642456055 Domain: biomedical Document type: Study Language: en Protein was extracted from TIB-71 cells for use in western blotting. For this purpose, the supernatant of the cells grown in the appropriate environment was separated for ELISA, whereas protein was extracted from the cellular pellets. Protein obtained using the Protein Extraction Kit (Abcam, Cambridge, UK) was prepared for western blotting. The concentrations of protein samples were determined using the Pierce BCA protein assay kit (Thermo Fisher Scientific). The results were analyzed by reading them on a 96-well plate reader at 565 nm. Section title: 2.5. Interleukin-6 (IL-6) Expression Analysis by Western Blotting Educational score: 4.065459251403809 Domain: biomedical Document type: Study Language: en IL-6 was separated by 12% (w/v) SDS-PAGE and transferred onto a PVDF membrane using the wet transfer technique to compare the expression levels of the markers. Proteins were measured using horseradish peroxidase (HRP)-based clarity western ECL substrate and read using ChemiDoc devices. The area of the bands obtained in the western blotting results was computed using Image Lab software. Section title: 2.5. Interleukin-6 (IL-6) Expression Analysis by Western Blotting Educational score: 3.9746599197387695 Domain: biomedical Document type: Study Language: en Specifically, the volume occupied by the bands on the membrane was determined, and the band volume of IL-6 was normalized to that of β -actin to assess protein expression in a semiquantitative manner. Section title: 2.5. Interleukin-6 (IL-6) Expression Analysis by Western Blotting Educational score: 2.3851521015167236 Domain: biomedical Document type: Study Language: en Microsoft Excel was used for the semiquantitative analysis. IL-6 secretion by mouse macrophages in response to AMP exposure was examined by GraphPad Prism 9.0.0 one-way ANOVA test (GraphPad, La Jolla, CA, USA). Section title: 3.1. Sequences and Properties of the Designed AMPs Educational score: 2.963550090789795 Domain: biomedical Document type: Study Language: en In this study, four peptide sequences, namely NET1, NET2, NET3, and NET4, were designed using d- and l-form amino acids. The properties of these peptides are presented shown in Table 1 . Section title: 3.2. Chemical Synthesis of AMPs and Purification by HPLC Educational score: 4.100997447967529 Domain: biomedical Document type: Study Language: en The Liberty Blue peptide synthesizer was used for the chemical synthesis of peptides. In each synthesis, the amounts of amino acids used and the amount of dimethylformamide (DMF) dissolved in milliliters were calculated by the software of the peptide synthesizer. The peptide peaks appeared at 50%–55% hydrophobicity. Purity levels were determined by the ratio of peak areas to the total peak areas, and they were above 95%. In the analytical HPLC results, a single peak was observed for each peptide . Section title: 3.2. Chemical Synthesis of AMPs and Purification by HPLC Educational score: 3.2162888050079346 Domain: biomedical Document type: Study Language: en The concentrations of the peptides were measured using the Pierce Quantitative Peptide Assays kit. Once the peptide concentrations were determined, the peptides were stored under appropriate conditions for use in the experiments ( Table 2 ). Section title: 3.3. Cytotoxicity Assay Results Educational score: 3.6099939346313477 Domain: biomedical Document type: Study Language: en The cytotoxicity of the synthesized peptides was determined in TIB-71 cells using the MTT method. The toxic effects of peptides at varying concentrations are extremely important for the vital activities of macrophages, which are members of the immune system. Section title: 3.3. Cytotoxicity Assay Results Educational score: 4.067872047424316 Domain: biomedical Document type: Study Language: en The MTT assay was performed separately with and without LPS. Figure 2 presents the results of cytotoxicity assays for various concentrations of the AMPs and Mag2. This experimental group was first tested in an LPS-free environment. NET1, NET2, and Mag2 did not cause significant cytotoxicity at concentrations up to 4 μ g/mL, and they were further evaluated in the presence of different LPS concentrations. The LPS-free wells were used as a control. Figure 3 presents the percent cytotoxicity in the presence of different concentrations of LPS and the peptides. Section title: 3.4. Investigation of IFN- γ Responses Educational score: 4.074692249298096 Domain: biomedical Document type: Study Language: en ELISA was employed to assess IFN- γ secretion into the TIB-71 cell supernatant in the presence of LPS (50 ng/mL) in and increasing concentrations of the peptides. The significance of the change in expression was determined by one-way ANOVA. p < 0.05 indicated statistical significance. The graph showing the amount of IFN- γ in the samples is shown in Figure 4 . The symbol “ ∗ ” means p ≤ 0.05, the symbol “ ∗∗ ” means p ≤ 0.01, and the symbol “ ∗∗∗ ” means p ≤ 0.001. Section title: 3.5. Investigation of TNF- α Responses Educational score: 4.037502765655518 Domain: biomedical Document type: Study Language: en TNF- α secretion from TIB-71 macrophages in the presence of LPS (50 ng/mL) and various concentrations of the peptides was examined by ELISA. One-way ANOVA was used to determine whether the changes in TNF- α responses were statistically significant. Figure 5 displays the concentrations of TNF- α in the samples. Section title: 3.6. Investigation of IL-6 Responses Educational score: 2.812039375305176 Domain: biomedical Document type: Study Language: en Images of the IL-6 bands obtained by western blotting and repeat probing of the membrane after stripping are presented in Figure 6 . Section title: 3.6. Investigation of IL-6 Responses Educational score: 3.8943076133728027 Domain: biomedical Document type: Study Language: en IL-6 expression was normalized to β -actin expression and compared with the control (unstimulated cells). The relationship between different experimental groups was examined statistically by one-way ANOVA. In Figure 7 , the fold changes in IL-6 expression in the presence of AMPs and LPS are presented. Section title: 4. Discussion Educational score: 4.069904804229736 Domain: biomedical Document type: Study Language: en This research examined the antimicrobial activities of peptides based on helical structure, a crucial component of the immune system that is found in a wide variety of organisms. These peptides have important roles in natural defenses, and they simultaneously participate with the secondary immune response. The emergence of AMPs and their increasing importance in recent years are also related to the resistance of microorganisms to antibiotics, which has led to a need for alternative drug or molecule candidates. The AMPs used in this study include peptides previously developed and used by Polat et al. . The peptides were resynthesized by solid-state synthesis and used in our experiments. Section title: 4. Discussion Educational score: 4.076303482055664 Domain: biomedical Document type: Study Language: en The 16-amino acid peptides used in this study were composed of two distinct amino acid types, namely the d- and l-forms. TIB-71 mouse macrophages were used in various tests to examine the effects of the peptides, the minimal inhibitory concentrations (MICs) of which in microorganisms were previously determined , on the immune system. We examined the interactions of the peptides with IL-6, IFN- γ , and TNF- α , which are important components structures of the immune system, through cytotoxicity assays, ELISA, and western blotting. Section title: 4. Discussion Educational score: 3.394028425216675 Domain: biomedical Document type: Study Language: en First, the peptides were synthesized and purified by HPLC, as presented in Figure 1 . The appearance of a single peak indicated that the peptide was pure and confirmed the absence of external molecules. Fluctuations observed before purification indicate impurities. Section title: 4. Discussion Educational score: 3.623037576675415 Domain: biomedical Document type: Study Language: en These contaminants can be attributed to the fact that the purification and analysis arms of the device were not completely washed. In addition, the rate at which the peptide is introduced into the system during HPLC also causes contamination. To eliminate these impurities, we collected the peptides injected into the system after analyzing the impurity. Each peptide gave a single peak in the system, and it was collected back in pure form . Section title: 4. Discussion Educational score: 4.0909013748168945 Domain: biomedical Document type: Study Language: en For cytotoxicity analysis, assays were conducted using macrophages, an immune system cell type that plays an effector role in many infectious diseases. In this context, TIB-71 mouse macrophages were chosen. The selectivity/safety index was calculated as a ratio of the MIC at which each AMP affects the microorganism to the concentration of AMP that causes 50% toxicity in the cells . The important finding of this assessment was that AMPs exhibited both low inhibitory effects and low toxicity . Section title: 4. Discussion Educational score: 4.076006889343262 Domain: biomedical Document type: Study Language: en To conduct a broad screening, treatment with the peptides was started at a concentration of 64 µg/mL and reduced to 0.125 µg/mL. In this context, Mag2, which served used as a reference, exhibited low toxicity at almost all concentrations. NET1 and NET2 displayed similar cytotoxicity, starting at a concentration of 4 µg/mL. In particular, NET2 exhibited lower toxicity than the other peptides, even at high concentrations. Because of low concentrations of NET1 and NET2 compared with the other peptides, subsequent studies continued with these two peptides, and the concentration range was 0.5–4 µg/mL. LPS, which had a highly toxic effect alone, as expected, exhibited lower toxicity when applied in combination with the AMPs. Section title: 4. Discussion Educational score: 4.017402648925781 Domain: biomedical Document type: Study Language: en At a concentration of 4 µg/mL, NET1 displayed the lowest toxicity. The toxicity of NET1 was increased threefold compared to that in the absence of LPS. The level of toxicity of NET2 was increased by tenfold compared to that in the absence of LPS. There were no significant changes in the cytotoxicity depending on the LPS concentration. The cytotoxicity of NET2 and Mag2 increased as the LPS concentration decreased. Section title: 4. Discussion Educational score: 4.02738094329834 Domain: biomedical Document type: Study Language: en The results were similar when the peptide concentration was 2 µg/mL. The cytotoxicity of NET2 and Mag2 peptides increased with as the LPS concentration decreased. On average, NET1 displayed lower cytotoxicity than NET2 regardless of the LPS concentration. NET1 also exhibited lower cytotoxicity in samples in which the peptide concentration was 1 µg/mL. Similarly, in this analysis, the cytotoxicity of the peptides increased as the LPS concentration decreased. Section title: 4. Discussion Educational score: 4.0246100425720215 Domain: biomedical Document type: Study Language: en Finally, in the analysis in which the peptide concentration was 0.5 µg/mL, decreased NET1 cytotoxicity was observed in response to decreasing LPS concentrations, whereas increased cytotoxicity was observed for NET2. Mag2 displayed a constant effect at all concentrations. This might be attributable to the slight mitogenic response to low levels of the peptide and LPS . Section title: 4. Discussion Educational score: 4.098974227905273 Domain: biomedical Document type: Study Language: en After cytotoxicity studies, ELISA was performed for NET1 and NET2 to assess IFN- γ secretion. In this context, the effects of the peptides both with and without LPS on IFN- γ secretion were investigated. The presence of LPS resulted in greater IFN- γ secretion than observed in unstimulated cells. When cells were treated with NET1 at three different concentrations in LPS-free medium, IFN- γ secretion increased significantly. IFN- γ secretion decreased as the peptide concentration decreased. When cells were treated with NET1 in the presence of LPS, a decrease IFN- γ expression occurred. Consequently, the secretion of IFN- γ also decreased. The expression of IFN- γ in cells stimulated with 8 µg/mL NET1 increased significantly at three different concentrations compared with the control level. Section title: 4. Discussion Educational score: 4.072177886962891 Domain: biomedical Document type: Study Language: en Meanwhile, NET2 induced lower IFN- γ expression than NET1. Moreover, with increasing concentrations of NET1, IFN- γ secretion increased, whereas the opposite was observed for NET2. Furthermore, in contrast to NET1, the IFN- γ response was stronger when NET2 and LPS were used as costimulators. In effector cells stimulated with NET2 and LPS, IFN- γ secretion was significantly increased. Section title: 4. Discussion Educational score: 4.320907115936279 Domain: biomedical Document type: Study Language: en Normally, the major sources of IFN- γ expression are T lymphocytes and NK cells. However, some studies revealed that this situation can change, and IFN- γ can be secreted by macrophages or different structures . This study illustrated that NET1 and NET2 significantly increased IFN- γ secretion, and NET2 displayed strong stimulatory properties in the presence of LPS. This situation, in which the effect changed in the presence and absence of LPS, was conspicuous in terms of its pro-inflammatory effect. Cytokine secretion, which becomes evident during acute inflammation, is effective against many infections. Studies should also be conducted with different cytokines to observe the immune effect of these peptides against various diseases. IFN- γ is involved in immune response modulation, including host defense against intracellular infections and tumors. IFN- γ facilitates Th1 differentiation, enhances macrophage activity, promotes leukocyte migration to the infection site, and increases major histocompatibility complex expression to improve T-cell identification of cancerous or infected cells. Nonetheless, uncontrolled IFN- γ expression in mice induces autoimmunity, and unchecked IFN- γ protein synthesis is likewise harmful to the host. Consequently, maintaining a balance between immunological tolerance and inflammation requires strict control over IFN- γ expression [ 17 – 19 ]. Section title: 4. Discussion Educational score: 3.2503538131713867 Domain: biomedical Document type: Other Language: en Cytokine secretion, which comes to the fore during acute inflammation, is effective against many infections. Studies should also be conducted with different cytokines to observe the immune effect of these peptides against diseases. Although their main job is to control inflammation, cytokines are essential for controlling the immune system in both health and illness. Cytokines are classified as either pro- or anti-inflammatory . Section title: 4. Discussion Educational score: 4.074991703033447 Domain: biomedical Document type: Study Language: en In this study, we examined the effects of NET1 and NET2 on TNF- α expression at the cellular level in the presence and absence of LPS. There was no change in its expression in cells exposed only to LPS compared with the control. Different concentrations of NET1 in LPS-free medium significantly increased TNF- α secretion by 50%. However, there was no significant difference according to the peptide concentration. In addition, the TNF- α response did not differ between cells simultaneously stimulated with the peptide and LPS and cells treated only with the peptide. Section title: 4. Discussion Educational score: 4.056703090667725 Domain: biomedical Document type: Study Language: en Similar results emerged in studies conducted with NET2. TNF- α secretion decreased with decreasing peptide concentrations in LPS-free medium. In the presence of LPS, the TNF- α response is stronger than that observed in the NET1 group. TNF- α secretion increased significantly, especially in the presence of 2 or 4 µg/mL NET2 combined with LPS. Studies conducted using lower peptide concentrations in an LPS-free environment have the potential to reveal anti-inflammatory effects [ 21 – 23 ]. Section title: 4. Discussion Educational score: 4.069925785064697 Domain: biomedical Document type: Study Language: en The findings illustrated that NET1 and NET2 might have anti-inflammatory effects. The results were evaluated on the basis of the amount of IL-6 released from the cells into the medium alone. In this context, the amount of IL-6 released from LPS-treated cells increased by 50%, consistent with the data in the literature . The long-term presence of IL-6 can cause chronic inflammation. Because of cellular treatment with NET1, the amount of IL-6 released into the medium was decreased. It is predicted that the peptides have anti-inflammatory effects. However, no concentration-dependent change was observed. The same result was obtained when the cells were treated with LPS alone, namely, decreased IL-6 expression. An important point is that at the lowest concentration of 2 µg/mL, IL-6 expression was threefold lower than observed in the other groups. Section title: 4. Discussion Educational score: 4.090531826019287 Domain: biomedical Document type: Study Language: en Similar results were obtained for NET2. When NET2 is used alone, IL-6 expression was 50% lower than that observed in NET1-treated cells. However, there was no significant change in IL-6 as the peptide concentration was decreased. When cells treated with LPS were then treated with NET2, an anti-inflammatory effect was recorded at a peptide concentration of 8 µg/mL. However, as the concentration was decreased, this effect disappeared, and IL-6 expression increased significantly. Both peptides induced the highest IL-6 expression at a concentration of 4 µg/mL in both the presence and absence of LPS. IL-6 expression was significantly increased by both 2 and 4 µg/mL NET2 in combination with LPS in comparison to the findings in the other groups. This might have been caused by the aggregation of peptides at low concentrations or disruption of peptide structures upon stimulation with LPS. Detailed studies should be conducted using a wide range of concentrations. Section title: 4. Discussion Educational score: 4.074535369873047 Domain: biomedical Document type: Study Language: en The aims of the study were to compare the effects of our synthesized peptide structures on the immune system and evaluated their effectiveness. Many AMPs are promising structures for the treatment of various diseases with two-way effects on the immune system, as they exhibit both pro-inflammatory and anti-inflammatory effects, especially in response to inflammation. In this context, NET1 and NET2 exhibited anti-inflammatory effects by decreasing IL-6 and TNF- α at certain concentrations, whereas pro-inflammatory effects were induced through IFN- γ . This situation is compatible with the literature, and by increasing the diversity of experiments and improving the peptide structures, new therapeutic structures could be generated. Section title: 4. Discussion Educational score: 4.4515299797058105 Domain: biomedical Document type: Study Language: en In addition, the use of some AMPs alone or in combination gave better results on immune system elements. For example, it has been observed that LL-37 peptide, used in combination as an innovative approach in ovarian cancer, has an antitumor effect and increases the activity of NK cells . In another example, macrophage transformation and effects of monocytes were examined using various stimuli in the presence of LL-37. Monocytes cultured with M-CSF were directed to macrophages with pro-inflammatory properties . A further instance of macrophage turnover and the balance of pro-inflammatory and anti-inflammatory cytokines, LL-37 peptide induced anti-inflammatory IL-10 while reducing TNF- α and IL-17. It also affected the production of TGF- β . Inflammatory effects are also observed in peptides that are not natural but produced in mutant form. For example, mutated chensinin-1 peptide blocked LPS-induced pro-inflammatory cytokines . In another example of structurally changed peptides, pseudin-2 peptide isolated from Pseudis paradoxa was structurally changed and its anti-inflammatory effects were examined . Also full Ala-scan can also be performed to reveal the effect on cells. Performing these tests can provide detailed insights into the effects of AMPs against pathogenic cells. The interactions between AMPs and cells are crucial for modifying the pathways needed to neutralize pathogens, including chemical, biological, and electrostatic interactions. Changes and improvements in the primary and secondary structures of peptides directly influence their effectiveness against pathogenic cells. Additionally, investigating the D-Ala-D-Ala structures, which are vital components of bacterial peptidoglycan and play a role in antibiotic resistance mechanisms, is essential. Modifying synthetically produced AMPs based on their mechanisms of action is also critical for developing innovative treatment products against pathogenic microorganisms. Furthermore, conducting a full Ala-scan could further elucidate the impact of these peptides on cells. Section title: 4. Discussion Educational score: 3.736328125 Domain: biomedical Document type: Study Language: en In this context, the NET1 and NET2 peptides we synthesized cause anti-inflammation at certain concentrations against IL-6 and TNF- α , while IFN- γ also causes pro-inflammation. This situation is compatible with the literature, and by increasing the diversity of experiments and improving the peptide structures we have obtained, it can lead to new generation therapeutic structures. Section title: 5. Conclusion Educational score: 3.9396722316741943 Domain: biomedical Document type: Study Language: en Based on the experimental results, we believe it is important to apply these peptides over a wider concentration range and determine their effects on different immune system elements. Investigating the effects on the AMPs on different IL molecules working together simultaneously or evaluating their effects on different cytokine groups could expand their applicability. Animal studies should also be conducted to investigate the effects and toxicity of the peptides at different doses. Section title: 5. Conclusion Educational score: 2.5604546070098877 Domain: biomedical Document type: Other Language: en The combined application of synthesized peptides could reveal product groups with high commercialization potential through studies conducted under both in vitro and in vivo conditions. | Review | biomedical | en | 0.999996 |
PMC11698615 | Section title: Introduction Educational score: 4.150434970855713 Domain: biomedical Document type: Clinical case Language: en Cystic artery pseudoaneurysms are a rare entity causing hemodynamically significant and life-threatening hemorrhages that are usually secondary to acute cholecystitis . Other etiologies for the development of cystic artery pseudoaneurysms are pancreatitis, cholelithiasis, and trauma during cholecystectomy . The incidence of vascular injury during cholecystectomy is low (0.2-0.5%) and pseudoaneurysms associated with laparoscopic cholecystectomy generally arise from the right hepatic artery. The pathogenesis of cystic or hepatic artery pseudoaneurysms is thought to be related to inflammatory damage and weakening of the adventitia caused by cholecystitis or pancreatitis, which may be exacerbated by manipulation, clip application, or thermal injury . Complications of cystic artery pseudoaneurysms are serious and can include bleeding into the biliary system or peritoneum necessitating resuscitation and requiring prompt intervention . We present a case of an iatrogenic cystic artery pseudoaneurysm arising as a complication of transjugular liver biopsy (TJLB). Section title: Introduction Educational score: 3.986464262008667 Domain: biomedical Document type: Other Language: en TJLB is a widely performed and useful technique in patients with severe coagulopathy and/or severe ascites . TJLB is performed via a needle introduced through a hepatic vein, without causing a transcapsular injury, so any bleeding related to the procedure will drain back into the venous system. Since it was initially described in 1964, many large studies have shown it is a safe technique with complications reported between 0.6% and 20%, the most common major complications being intraperitoneal bleeding, vessel injury, or ventricular arrhythmia . In the present case, due to patient-specific anatomy, the biopsies were taken from an accessory hepatic vein resulting in a traumatic cystic artery pseudoaneurysm. Section title: Case presentation Educational score: 2.6496901512145996 Domain: clinical Document type: Clinical case Language: en A 52-year-old male was originally admitted with complaints of abdominal pain and chills. His past medical history includes alcoholic liver cirrhosis (model for end-stage liver disease {MELD}-Na 30, Child-Pugh Class C). He was being evaluated for liver transplantation. Interventional radiology was consulted for transjugular hepatic pressure measurements and liver biopsy. Section title: Case presentation Educational score: 3.603177309036255 Domain: clinical Document type: Clinical case Language: en Pre-procedural lab work showed an international normalized ratio (INR) of 3.6, fibrinogen of 81 mg/dL, 67 platelets/µL, and hemoglobin of 11.6 g/dL. After the transfusion of two units of fresh frozen plasma and cryoprecipitate, the INR and fibrinogen improved to 2.7 and 152 mg/dL, respectively. Section title: Case presentation Educational score: 3.9617350101470947 Domain: clinical Document type: Clinical case Language: en At the start of the procedure, the right internal jugular vein was accessed under ultrasound guidance utilizing a micropuncture system (Bloomington, IN: Cook Medical), and a 10-french Check-Flo sheath (Bloomington, IN: Cook Medical) was placed. Through the sheath, a multipurpose angled catheter (Shibuya, Japan: Terumo) was used to access a hepatic vein. Multiple attempts were made to access the main right hepatic vein; however, this was not possible due to sharply angulated anatomy at the venous origin. Selective free hepatic venography was performed showing the catheter within an accessory right hepatic vein . At this point, a Fogarty balloon catheter (Irvine, CA: Edwards Lifesciences) was advanced into the accessory hepatic vein, and pressure recordings were obtained with a portosystemic gradient of 20 mmHg. Next, the Rösch-Uchida transjugular liver access set and Quick-Core Biopsy Needle (Bloomington, IN: Cook Medical) were placed within the accessory hepatic vein and two core needle biopsies were then taken through the system . Multiple venograms throughout the procedure, before and after the biopsy, showed that the sheath was persistently within the hepatic vein. After the removal of the sheaths, hemostasis was obtained at the internal jugular vein using manual compression. Section title: Case presentation Educational score: 3.62160587310791 Domain: clinical Document type: Clinical case Language: en Post-procedurally, the patient’s hemoglobin steadily trended down from pre-procedural values of 11.6 g/dL to 6.4 g/dL despite transfusion of multiple units of packed red blood cells. Multiphasic computed tomography angiogram of the abdomen was performed which showed arterial phase contrast extravasation into the gallbladder lumen with pooling of contrast in the lumen on delayed phases . The patient was then taken back to the fluoroscopy suite for a mesenteric angiogram with possible embolization. Section title: Case presentation Educational score: 3.9620397090911865 Domain: biomedical Document type: Clinical case Language: en The micropuncture kit was used to access the right common femoral artery and a 6-french access sheath (Shibuya, Japan: Terumo) was placed. The celiac and superior mesenteric arteries were catheterized using a C2 catheter (Bloomington, IN: Cook Medical). Angiograms from the celiac artery showed a faint vascular blush in the gallbladder. The proximal gastroduodenal artery was accessed through a microcatheter system using a Progreat microcatheter (Shibuya, Japan: Terumo) and Fathom microwire (Marlborough, MA: Boston Scientific). Superselective angiograms from the proximal cystic artery showed a 3 x 3 mm pseudoaneurysm with contrast blush into the gallbladder lumen arising from the distal superior division of the cystic artery . Irregular traumatized vessels were also seen at the superior aspect of the gallbladder. Section title: Case presentation Educational score: 3.8366246223449707 Domain: clinical Document type: Clinical case Language: en The microsystem was advanced to the superior division of the distal cystic artery, and embolization was performed using Nester metallic coils (Bloomington, IN: Cook Medical). Post-embolization angiogram from the cystic artery demonstrated continued filling of the pseudoaneurysm from the inferior division of the cystic artery . The inferior division was similarly embolized with metallic coils with post-embolization angiography from the cystic artery demonstrating no filling of the previously seen pseudoaneurysm as well as no active extravasation . Section title: Case presentation Educational score: 3.067483425140381 Domain: clinical Document type: Clinical case Language: en Hemostasis of the right common femoral arteriotomy site was achieved using a StarClose SE closure device (Chicago, IL: Abbott Laboratories). The patient tolerated the procedure well and required no further blood products during admission and was discharged on post-operative day six. The patient has been listed on the liver transplant waiting list at this time and is awaiting transplantation. He has undergone a repeat multiphasic computed tomography angiogram for hepatocellular carcinoma screening without evidence of pseudoaneurysm recurrence, non-target embolization, or complication secondary to endovascular embolization. Section title: Discussion Educational score: 4.074123382568359 Domain: biomedical Document type: Clinical case Language: en Cystic artery pseudoaneurysms are a rare entity that generally arise from complications associated with acute cholecystitis. We present a case of an iatrogenic cystic artery pseudoaneurysm after TJLB with biopsy samples taken from an accessory right hepatic vein. Given the unfavorable right main hepatic vein anatomy in this patient, TJLB through the accessory vein was thought to be less risky for the patient than conversion to a percutaneous approach. Sampling from the accessory right hepatic vein is an accepted approach; however, it has been reported to be associated with an increased risk of complications, including direct arterial injury, liver capsule perforation, or even accidental renal sampling . In the present case, biopsies taken from this position likely caused trauma to the superior division of the distal cystic artery and resultant hemorrhage and hemobilia. Section title: Discussion Educational score: 3.960031270980835 Domain: biomedical Document type: Review Language: en Transarterial embolization has been shown to have an approximately 95% success rate in treating post-laparoscopic cholecystectomy cystic and hepatic artery pseudoaneurysms, with less morbidity and mortality than repeat surgery . However, approximately 88% of pseudoaneurysms associated with laparoscopic cholecystectomy arise from the right hepatic artery. Only a few cases have been reported to be secondary to TJLB, and of these cases, the traumatized artery is a branch of the hepatic artery . The present literature review did not identify the case of cystic artery pseudoaneurysm after TJLB. Section title: Conclusions Educational score: 3.839216709136963 Domain: clinical Document type: Clinical case Language: en Cystic artery pseudoaneurysms are rare complications usually associated with acute cholecystitis and laparoscopic cholecystectomy. We discussed a rare case of iatrogenic cystic artery pseudoaneurysm after TJLB. This rare yet life-threatening complication impacts patient outcomes. This case raises the idea that close post-procedure monitoring for hemodynamic instability or changes in laboratory parameters after TJLB may be warranted in patients with risk factors for hemorrhage, such as baseline coagulopathy to rule out rare yet morbid complications such as iatrogenic cystic artery pseudoaneurysm. | Clinical case | biomedical | en | 0.999996 |
PMC11698687 | Section title: Introduction Educational score: 3.9863016605377197 Domain: biomedical Document type: Review Language: en A healthy placenta is essential for fetal well-being because it delivers oxygen and nutrients and removes carbon dioxide and other waste products 1 . The placenta also functions as an intermediary between the maternal immune system and the fetus and protects the fetus from pathogens 2 . Recent placental research has focused on diverse aspects of placental function, maternal-fetal health, and potential therapeutic applications. Studies have explored the impact of environmental factors on placental health, investigated the levels of non-essential trace metals and their effects on placental function 3 . Research has also emphasized the critical role of timely medical intervention in placental complications, which comes from a study linking maternal late hospital arrival with adverse fetal outcomes in placental abruption cases 4 . Section title: Introduction Educational score: 4.231472969055176 Domain: biomedical Document type: Study Language: en In a normal human pregnancy, the intrauterine immune response starts as soon as implantation 5 . The placental immune response evolves across the gestation, and each trimester is characterized by a unique inflammation environment 6 . The accumulation of immune response could trigger the labor onset 7 . Several types of immune cells function in the placenta 8 , 9 . In a healthy placenta, uterine or decidual natural killer (NK) cells, maternal/fetal macrophages, dendritic cells, and regulatory T cells participate in spiral artery remodeling and trophoblast invasion. In pathological scenarios, additional immune cells often infiltrate the placenta. For example, neutrophils enter the placenta in cases of chorioamnionitis, chorionic vasculitis, and acute villitis 10 ; eosinophils enter the placenta in cases of intervillous thrombosis, cysts, and chorionic vasculitis 11 ; basophils enter the placenta in cases of acute placental infarction 11 ; increased macrophages enter the placenta in cases of listeria, tuberculosis, syphilis, acute atherosis, and villitis of unknown etiology 12 – 14 ; and CD4 + T cells significantly increase in cases of villitis of unknown etiology 15 . However, most of our knowledge of these processes in humans comes from immunohistochemistry of the ex vivo placenta after delivery. To longitudinally monitor immune infiltration of the placenta in pregnancy, we need a safe, non-invasive, and accurate imaging modality. Section title: Introduction Educational score: 4.5712890625 Domain: biomedical Document type: Review Language: en Current imaging techniques for monitoring placental conditions, such as ultrasound and computed tomography (CT), have significant limitations. Ultrasound is widely used for placental assessment due to its cost-effectiveness and real-time imaging capabilities. However, its accuracy can be compromised by factors like maternal obesity and bladder fullness. Additionally, ultrasound resolution diminishes in the later stages of pregnancy, making image interpretation challenging due to low contrast. Moreover, ultrasound is not sensitive to detecting placental inflammation. While CT can be valuable for assessing trauma during pregnancy, its use is restricted by the risks associated with ionizing radiation exposure, limiting its broader application for routine placental monitoring. As an emerging clinical imaging tool in the field of Obstetrics and Gynecology, MRI forms high-quality and multi-contrast 3D images using water molecules, which are naturally abundant in the human body. Therefore, MRI can be employed repeatedly in longitudinal studies to assess human pregnancy. Latest advancements in MRI, such as diffusion-relaxation MRI and T2*-weighted MRI, have become an important tool in placental research. Diffusion-relaxation MRI have been used to detect altered placental development in pregnancies affected by congenital heart disease (CHD). A study found significant differences in placental microstructure and perfusion between CHD-affected pregnancies and controls, particularly after 30 weeks’ gestation 16 . T2*-weighted placental MRI has been investigated as both a basic research tool and a potential clinical test for placental dysfunction. This imaging technique shows promise in directly reflecting placental function, which could significantly improve antenatal screening for placental dysfunction 17 . Especially, diffusion MRI (dMRI) enables the researcher to image and quantify the great complexity and heterogeneity in human placental microstructure 18 . In hemodynamic studies, dMRI enabled the exploration of the blood flow in the healthy placenta 19 and the mal-perfusion in pre-eclampsia 20 . dMRI was also used to track the myometrium alternation induced by placenta accrete 21 . In addition, merging dMRI with other MR contrasts brings new insight into the compartment-wise oxygenation property 22 . Section title: Introduction Educational score: 4.17596435546875 Domain: biomedical Document type: Study Language: en Although dMRI was successfully applied to detect inflammation in brain and other organs 23 – 25 , its placenta application has not yet yield imaging biomarkers specific to placental inflammation. To overcome a similar challenge of measuring neuro-inflammation in vivo in human brain, DBSI was successfully developed 26 , 27 . This advanced dMRI method is able to disentangle the highly restricted intracellular diffusion signal associated with cellularity from the diffusion associated with other microstructural components. DBSI has been extensively validated in the brain to detect increased cellularity during inflammation demyelination 26 and other forms of neuroinflammation in tumors 28 . Here, we customized DBSI based on the unique placental microenvironment to image immune cell infiltration in the human placenta. We performed ex vivo and simulation experiments to develop and validate the method and then used it for in vivo longitudinal analysis of the placenta. We found that our in vivo placental DBSI method reveals an increasing immune response after the first trimester, particularly in the placenta tissues compartment. We also discovered greater immune cellularity in placentas with pathology-defined signs of inflammation than in placentas without signs of inflammation at as early as 11–13 weeks’ gestation. Section title: Demographic information Educational score: 4.195740222930908 Domain: biomedical Document type: Study Language: en A total of 91 patients were enrolled in the study, and 239 MRI scans were scheduled, ranging from 12 to 38 weeks. MRI scans were scheduled on the same day as the patients’ regular obstetric visits at approximately 12, 20, 32, and 36 weeks’ gestation. A few patients were dual enrolled in other studies and thus underwent additional MRI scans. 202 scans from 82 patients were analyzed after excluding unfinished scans and poor-quality scans which are not sufficient to be analyzed by DBSI. At delivery, placentas from all participants were collected for pathologic and single-nucleus RNA sequencing examination. We used the pathological diagnosis to divide the cohort into two groups. The placentas of 12 patients were defined as the inflammation group (Table 1 , Supplemantary Table 1 ). The placentas from 70 patients did not have any of these diagnoses and were defined as the non-inflammation group. There were no significant differences in age (29.17 ± 4.15 years vs. 29.28 ± 4.98 years) or body mass index at delivery (27.42 ± 5.89 kg/m 2 vs. 28.04 ± 5.79 kg/m 2 ) between the inflammation and non-inflammation groups. A subset of the non-inflammation group (50 scans from 17 patients) who have additional T2* scans was used to conduct intra-placental segmentation. To perform ex-vivo validation, we obtained the ex-vivo MRI and immunohistochemistry (IHC) from five placenta after delivery. Among the five IHCs, we built 3D geometry on 400 0.25 × 0.25 mm 2 regions and conducted a Monte Carlo simulation. Table 1 Demographic and clinical information Age BMI Gestational age Pathology Non-inflammation group ( n = 70) 29.28 ± 4.98 28.04 ± 5.79 266.58 ± 20.62 Inflammation group ( n = 12) 29.17 ± 4.15 27.42 ± 5.89 265.83 ± 18.12 Pt #1 36 23.16 281 Multifocal villitis with associated intervillositis Fetal membrane with pigmented amniotic macrophages. Pt #7 31 28.34 274 Fetal membranes with numerous pigment-laden amniotic macrophages Pt #14 20 18.54 280 Fetal membrane with moderate acute chorioamnionitis Trivascular cord with modera funisitis Pt #35 27 25.97 263 Acute chorionitis Trivascular cord with umbilical arteritis Pt #42 26 33.80 278 Fetal membranes with numerous pigmented amnionic macrophages Chronic lymphohistiocytic villitis, non-necrotizing Pt #44 29 28.30 277 Chronic lymphohistiocytic villitis Increased perivillous fiberinoid deposition, approximately 10% of volume Pt #48 32 22.04 260 Chronic lymphohistiocytic villitis, mild/focal, non-necrotizing Pt #50 29 35.98 243 Acute chorionitis Pt #60 27 20.45 220 Fetal membrane with acute chorioamnionitis Pt #109 34 25.14 264 Incidental septal cyst (2 cm in greatest dimension) Pt #112 28 32.01 273 Intervillous fibrin Peripheral placental cyst with 0.9 cm greatest dimension. Pt #116 31 35.35 277 Fetal membranes with pigmented amniotic macrophages Mild acute chorioamnionitis p -value 0.88 0.76 0.90 Section title: Development and validation of a whole placenta DBSI method to identify immune cells Educational score: 4.167963981628418 Domain: biomedical Document type: Study Language: en In DBSI, “dictionaries” are used to disentangle diffusion characteristics of water molecules in and around multiple cellular components within an imaging voxel . For this study, we were most interested in distinguishing immune cells from other cells in the placenta. To do so, we took advantage of the large difference in the sizes of placental cells. Using the placenta collected in this study, single-nucleus RNA sequencing (snRNA-seq) was conducted to determine the composition of cell types in the placenta . Fig. 1 Schematic demonstration of diffusion basis spectrum imaging (DBSI) methodology. A Schematic of a Magnetic Resonance Imaging (MRI) voxel that contains several microstructures. B Schematic of measured diffusion signals from the voxel. C Diffusion dictionary assembled from prior knowledge. D DBSI-derived spectrum. E The dictionary corresponds to placental cells of different radii: T cells, 2–3 µm; natural killer (NK) cells, 3–4 µm; B cells, 4–5 µm; neutrophils, 6–7 µm; dendritic cells (DC), 7–10 µm; macrophages, 10–11 µm; cytotrophoblasts (CTB), syncytiotrophoblast (STB), extravillous trophoblasts (EVT), and decidua stromal (dS) cells, and other placental resident cells, >10 µm. F t-distributed stochastic neighbor embedding (tSNE) map of variant types of placental cells and their percentage, which were annotated (and labeled from blue color to red color, correlated to Diffusion Dictionary) by single-cell RNA sequencing. Section title: Development and validation of a whole placenta DBSI method to identify immune cells Educational score: 4.203166484832764 Domain: biomedical Document type: Study Language: en The decidua is largely composed of round decidual and trophoblast giant cells, and the chorionic plate is mainly composed of fetal blood vessels embedded in fetal stromal tissue, lined by trophoblastic cells. Those decidual and trophoblast cells are usually over 40 µm in the largest dimension, and many have irregular shapes. The chorionic villi are mainly composed of cytotrophoblasts, which have a radius over 20 µm, and syncytiotrophoblasts, which are formed by the fusion of many cytotrophoblasts. In contrast, immune cells are generally less than 8 µm in radius. Thus, we conducted a Monte-Carlo simulation on cell structures with a radius of 8 µm (Supplementary Material 3 ). The computed cell apparent diffusion coefficient (ADC) was 0.6 mm 2 /msec. Therefore, our DBSI analysis method extracted placental immune cells from the isotropic spectra by using ADC values between 0.01 and 0.6 mm 2 /msec . Section title: Development and validation of a whole placenta DBSI method to identify immune cells Educational score: 4.145575523376465 Domain: biomedical Document type: Study Language: en To determine whether DBSI could be used to assess immune cell infiltration in the placenta accurately, we performed ex vivo validation. We obtained samples from five placentas after delivery, embedded them in agar, and performed ex vivo MRI. We then bisected the samples, fixed them, embedded them in paraffin, cut sections, and performed IHC with an anti-CD4 antibody . We quantified the CD4-positive area and used landmarks to register the IHC-derived immune cell density maps with DBSI-derived immune cell density maps . Qualitatively, we found similar patterns in all samples in the DBSI-derived and IHC-derived maps . Linear regressions of the data from all five samples showed significant correlations (r 2 between 0.38 and 0.71, p < 0.001). Moreover, the estimated slopes from the linear regressions were all close to 1 . Fig. 2 Correlation between DBSI- and immunohistochemistry-derived immune cell densities. A Raw immunohistochemistry (IHC) images of CD4 staining. B Positive stain area ratio on CD4 IHC, registered to the corresponding DBSI image. Images at the far right are high-magnification views of indicated regions in raw CD4 staining images. C DBSI-estimated immune cell density. The IHC- and DBSI-derived maps share the same heatmap keys. D Correlation between the DBSI- and IHC-derived immune cell densities. Each point represents the mean value in a 5-by-5 pixel patch in ( A ) and ( B ). The 95% confidence intervals of the linear regressions are shaded green. The dashed line has a slope of 1 and is shown as a reference. Section title: Development and validation of a whole placenta DBSI method to identify immune cells Educational score: 4.151553153991699 Domain: biomedical Document type: Study Language: en To assess our method’s sensitivity and noise resistance, we built a Monte Carlo simulated three-dimensional microstructure geometric model derived from histology images collected in this study . We then simulated diffusion MRI signals with different signal-to-noise ratios consistent with the ranges observed in ex vivo and in vivo MRI data (58.6 ± 7.9 and 37.4 ± 3.7, respectively). We simulated 400 0.25 × 0.25 mm regions on histology images. There was a significant linear correlation between the simulated MRI-derived cell density and the IHC-derived cell density under signal-to-noise ratios of 75 to 25 . Fig. 3 Monte Carlo simulation of diffusion MRI based on histology images. A CD4 staining of a placenta specimen. Four representative regions were selected (boxes). B Hexagonal prisms were used to model placental resident cells. C A tube surrounding the entire villus was used to model the syncytiotrophoblast layer. D Water molecules were placed outside the villous model to simulate diffusion in the intervillous space. E Spheres of radius 4–8 µm were placed where CD4 positive stain was detected to represent immune cells. F Diffusion trajectories from the example random seeds in the four structures. G Built a 3D model based on the histology image in ( A ). The entire 3D model covers a 5 × 5 mm region and is the input for the Monte Carlo simulation. The model was divided into 400 0.25 × 0.25 mm regions, one of which is illustrated in the dashed-line box. Hexagonal prisms representing resident cells are marked grey, models representing syncytiotrophoblasts are marked blue, and spheres representing immune cells are marked red. H Diffusion MRI signals were simulated in 400 0.25 × 0.25 mm regions with various signal-to-noise ratios. The simulated MRI- and IHC-derived immune cell densities were compared by linear regression. The green line shows the linear regression and 95% confidence range. The red dashed line has slope of 1 and is shown as a reference. Section title: DBSI analysis of placentas in vivo Educational score: 4.170284271240234 Domain: biomedical Document type: Study Language: en We first used DBSI to identify the placental regions that had the most immune cell infiltration. To do so, we used our previously developed and published intra-placental segmentation method based on T2* and diffusion MRI to divide the placenta into three major compartments: intervillous space, placental vessels, and placental tissue 29 . We combined this method with the placental DBSI analysis on 50 MRI scans from 17 patients in the non-inflammation group who have both T2* and diffusion MRI scans. Figure 4A–D shows images from a representative patient (29 years old, viable male infant delivered at 39 weeks and 4 days) imaged at 36 weeks’ gestation. The highest voxel-wise cellularity ratio was in the placental tissue region . We then combined all the data from the 17 patients and analyzed them in two ways. First, we used linear regression to examine the cellularity ratio in each placental region at multiple time points in pregnancy . This analysis revealed that cellularity was significantly greater in the placental tissue region late in pregnancy than early in pregnancy . Second, we compared cellularity between the compartments at each time point . This analysis showed that cellularity was significantly greater in the placental tissue region than in the placental vessels or intervillous space regions at 32 weeks’ gestation ( p < 0.05) and 36 weeks’ gestation ( p < 0.01) . Fig. 4 Cellularity ratio in each placental compartment. A – D Representative cellularity maps in the intervillous space (IVS), placental vessels (PV), placental tissue (PT), and total placenta are illustrated in heat maps. E Boxplots of voxel-wise cellularity ratio in the representative placental regions in ( A – D ). F – I Linear regressions of the mean cellularity ratios in each compartment and entire placenta. The colored region indicates a 95% confidence interval. J – L Comparison of mean cellularity in each visit (20/32/36 weeks). In the box plots, the horizontal line indicates the median, the + indicates the mean, the edges of the box indicate the 25th and 75th percentiles and the whiskers indicate 95% confidence intervals. * p < 0.05, ** p < 0.01, **** p < 0.0001 by Wilcoxon Rank-Sum test. Section title: DBSI analysis of placentas in vivo Educational score: 4.103135108947754 Domain: biomedical Document type: Study Language: en Next, we compared our placental DBSI data from the two groups of placentas: non-inflammation and inflammation. To visualize and compare the immune cell density in the two groups, we plotted the color-coded immune cell density maps on top of the anatomical reference T2 weighted images. Figure 5A–F shows four axial views of different MRI slices from one representative non-inflammation placenta and from one representative inflammation placenta (patient #109, see Supplementary Table 1 for details) at 20, 32, and 36 weeks’ gestation. Qualitatively, immune cell density appeared higher in the inflammation placenta than in the non-inflammation placenta . In both placentas, voxel-wise cell density increased over pregnancy . Fig. 5 Longitudinal progress of placental cellularity in two representative placentas. A – F Placental cellularity map at 20, 32, and 36 weeks’ gestation from ( A – C ), a patient in the non-inflammation group, and ( D – F ), a patient in the inflammation group. Background gray scaled images are T2WI. Cellularity ratios >0.01 are depicted in heat maps. G , H Boxplots of voxel-wise placental cellularity ratio across three-time points in the two patients. In the box plots, the horizontal line indicates the median, the + indicates the mean, the edges of the box indicate the 25th and 75th percentiles and the whiskers indicate 95% confidence intervals. **** p < 0.0001 by Wilcoxon Rank-Sum test. Section title: DBSI analysis of placentas in vivo Educational score: 4.074172496795654 Domain: biomedical Document type: Study Language: en We asked whether there were group-wise differences in immune cellularity between non-inflammation and inflammation placentas. We performed linear regressions on the mean placental cellularity ratios for each of the two groups . Cellularity was significantly greater later in pregnancy than earlier in the non-inflammation group but not in the inflammation group . Throughout pregnancy, the cellularity ratio was significantly higher in the placentas from the inflammation group than in the placentas from the non-inflammation group . This difference was significant at each of the four time points ( p < 0.01) . Fig. 6 Longitudinal placental mean cellularity. A , B Mean cellularity ratio in the ( A ) non-inflammation group and ( B ) inflammation group. C Combined plot of ( A ) and ( B ). D Mean placental apparent diffusion coefficient (ADC) in both groups; blue indicates non-inflammation, and red indicates inflammation group. In ( A – D ), colored regions indicate 95% confidence intervals. E – H Comparison of cellularity ratio between the two groups at the indicated weeks’ gestation. In the box plots, the horizontal line indicates the median, the + indicates the mean, the edges of the box indicate the 25th and 75th percentiles and the whiskers indicate 95% confidence intervals. ** p < 0.01; *** p < 0.001 by Wilcoxon Rank-Sum test. Section title: DBSI analysis of placentas in vivo Educational score: 4.057076930999756 Domain: biomedical Document type: Study Language: en Finally, to compare DBSI to another MRI method, diffusion tensor imaging, we examined mean ADC in non-inflammation and inflammation placentas. Diffusion tensor imaging-derived ADC values did not differ between non-inflammation and inflammation placentas at any time point (Supplementary Material 5 ). Moreover, in a linear regression of ADC values, the non-inflammation and inflammation groups did not significantly differ from each other . This finding suggests that diffusion tensor imaging failed to distinguish between the non-inflammation and inflammation groups compared to DBSI. Section title: Discussion Educational score: 4.108776092529297 Domain: biomedical Document type: Study Language: en Herein, we developed and validated a DBSI method to image and quantify immune cell density in the human placenta across gestation. Additionally, we used our method to reveal placental differences between non-inflammation and inflammation cases, as defined by the placental pathology reports after delivery. Our method could detect significant differences in immune infiltration as early as 11–13 weeks’ gestation. With further clinical validation, this DBSI method could be used clinically to identify pregnant patients with excess placental inflammation. Early detection would allow for timely interventions, such as enhanced monitoring or anti-inflammatory treatments, potentially preventing complications like preeclampsia or preterm birth. This approach could enable more personalized management of high-risk pregnancies, significantly improving both maternal and fetal outcomes. Section title: Discussion Educational score: 4.156816482543945 Domain: biomedical Document type: Study Language: en The DBSI metric of cellularity revealed significant differences between the non-inflammation and inflammation placentas, whereas the standard diffusion tensor imaging metric of ADC did not differentiate between the two groups. This difference is likely because diffusion tensor imaging cannot distinguish different diffusion components within an imaging voxel, so ADC reflects the average water diffusion across all placental microstructure components within the same voxel. In contrast, DBSI can specifically detect diffusion of water molecules within cells of a defined size range to reflect placenta immune cellularity. Specifically, the DBSI method can successfully image the immune cellularity in the human placenta by taking advantage of the fact that immune cells are generally much smaller than other cells in the placenta. Section title: Discussion Educational score: 4.14508056640625 Domain: biomedical Document type: Study Language: en To strictly establish DBSI in accurately imaging and quantifying placenta immune cells, we conducted a careful validation study using the placenta collected in this study. Based on the RNA-sequencing results , we found the majority of placental immune cells were CD4 positive. We also conducted and tested other IHCs, including CD3, CD68, and CD79a, but none of them showed significant enough positive stains, similar to previously published studies 15 , 30 , so we did not include the data and results from other IHCs. Hence, we decided to validate the accuracy of the DBSI method by comparing it to IHC with an antibody specific to CD4. Our landmark-based voxel-to-region registration method allows accurate alignment between IHC and DBSI images, which enables quantitative, voxel-wise comparison between DBSI- and IHC-derived cellularity maps over the entire placenta tissue sections. In addition to IHC validation, our Monte Carlo computer simulation revealed that the DBSI method is accurate with signal-to-noise ratios as low as 25 dB on non-diffusion weighted b0 images. This is much lower than the typical signal-to-noise ratios of 50–75 dB in ex vivo MRI. Given our ex vivo and simulation data, we concluded that our DBSI method can sensitively and accurately image and quantify immune cell density in the placenta. Taken together, the validation measures all suggest that DBSI can accurately reflect in vivo inflammation in the placenta. Section title: Discussion Educational score: 4.226910591125488 Domain: biomedical Document type: Study Language: en Our finding that inflammation significantly increased across pregnancy in the placental tissue compartment is consistent with previous reports that immune cells reside in the placental parenchyma and accumulate during pregnancy. Additionally, recent studies show that NK and T cells increase and differentiate in late gestation 31 , and neutrophils and macrophages infiltrate the placenta from the myometrium in late pregnancy to prepare for labor 32 , 33 . The immune cellularity in the placental vessel compartment was consistently low (around 5%) over pregnancy. Work from others suggests that immune cells in this compartment help to protect the fetus from infections 34 and maintain uterine homeostasis 35 . The immune cellularity in the intervillous space was also consistently low (around 5%) over pregnancy. Mucosal-associated invariant T cells have been identified in the intervillous space and shown to accumulate upon bacteria stimulation 36 . Section title: Discussion Educational score: 3.898780584335327 Domain: biomedical Document type: Study Language: en In this study, we are especially intrigued by our observation of localized cellularity in the inflammation placenta in Fig. 5D–F . On pathology, this placenta was noted to have a 2.5 cm cyst, but its location was not noted in the pathology report, so we were unable to determine whether it corresponded to the location of high cellularity. By conducting ex vivo DBSI of whole placentas in future studies, we may be able to identify DBSI features that reflect pathological observations. Section title: Discussion Educational score: 4.102150917053223 Domain: biomedical Document type: Study Language: en In group-wise analysis, we found that immune cell density increased as pregnancy progressed in the non-inflammation group. This finding is consistent with previous observations that placental inflammation increases from second to third trimester 6 , 37 and can trigger uterine contractions, cervical ripening and dilation, and placental separation 38 – 40 . Hence, placental inflammation has been suggested as a mechanism responsible for both term and preterm labor onset 41 , 42 . In future work, we will perform DBSI at more time points near the end of pregnancy to determine whether we can predict the onset of labor. Section title: Discussion Educational score: 4.111335754394531 Domain: biomedical Document type: Study Language: en This study has serval limitations. First, immune cells have more complex geometries than the isotropic models we used in DBSI. As we defined any cell of radius less than 8 µm to be an immune cell, we could not assess the dynamic composition of different types of immune cells during pregnancy. In addition, relying solely on CD4+ cells as a marker for DBSI validation could overlook the presence of other immune cell types, potentially limiting the scope and comprehensiveness of the analysis. In future work, we can overcome these limitations by combining high-resolution immune cell 3D geometries with Monte Carlo simulations to develop more realistic diffusion signal models of various placental immune cells in DBSI. Additionally, in future studies, we plan to utilize more specific immune cell markers in IHC beyond CD4+ to enhance the accuracy and depth of the analysis. And we will also include more pathological data of patients for more comprehensive analysis. Second, we were unable to perform intra-placental segmentation in inflammation placentas in this study due to the significant motion of the fetus, uterus, and placenta during the imaging session. In future work, we aim to enroll more patients from both non-inflammation and inflammation placentas and conduct more high-quality compartment-based analyses, especially for the inflammation group, to determine whether particular regions of the placenta are more prone to immune cell infiltration based on the different pathologies behind it. Third, we did not account for potential confounders such as comorbidities, medication use, multiple gestations, and fetal anomalies in this study. In future research, we will incorporate these factors, as they may influence placental inflammation in human subjects. Section title: Patient enrollment Educational score: 3.3749094009399414 Domain: biomedical Document type: Study Language: en This study was approved by the University’s Institutional Review Board, and all participants signed informed consent forms. Potential participants were included if they had a singleton pregnancy with no identified fetal anomalies at recruitment (before 12 weeks’ gestation) and intended to receive obstetric care and deliver at our institution. To make our study cohort homogenous, potential participants were excluded if they had multiple gestations, had a major fetal anomaly or had contraindications to MRI. Section title: In vivo MRI scans Educational score: 4.147809028625488 Domain: biomedical Document type: Study Language: en MRI was performed on a 3 T Siemens Vida scanner (Siemens, Erlangen, Germany). Diffusion MRI of the entire uterus was acquired by a 2D EPI sequence in 86 different weightings (directions are the same as those in ex-vivo), with a max b-factor of 900 s/mm 2 . Eight b0 images were placed across the entire diffusion MRI scans. Other acquisition parameters were: 12.8 s repetition time, 62 ms echo time, in-plane resolution of 3 mm by 3 mm, and slice thickness of 3 mm. The total scan time was approximately 22 min. The Echo train of additional T2* MRI were: [3, 5.11, 7.2, 9.3, 11.4, 13.5, 15.6, 17.7, 19.8, 21.9, 24] (msec). The in-plane resolution was 4 mm by 4 mm, and the slice thickness was 4.2 mm. The FOV of Both T2* and diffusion MRI covers the entire placenta. Section title: Post delivery Educational score: 4.06790828704834 Domain: biomedical Document type: Study Language: en This was a retrospective study, and we sorted the dMRI data into two groups based on post-delivery pathology. For all enrolled patients, the placenta was collected post-delivery for routine gross and histological exams performed by a board-certified pathologist with expertise in placental pathology (I.H.). Patients were divided into two groups (inflammation/non-inflammation) based on the findings on the pathology report: placenta noted to have villitis, chorioamnionitis, funisitis, chorionitis, or infarction and were defined as the inflammation cases. A subset ( N = 13) of placenta samples were collected for single-nucleus RNA sequencing test. Placenta specimens were cut from a subset ( N = 5) of placenta for ex-vivo validation between MRI and IHC and simulation validation. Section title: snRNA-seq Educational score: 4.094318866729736 Domain: biomedical Document type: Study Language: en snRNA-seq was performed with 10X Genomics technology using the placental tissues collected in this study ( www.10Xgenomics.com ). Placental cell types and their relative percentages were annotated and visualized with t-distributed stochastic neighbor embedding (tSNE) (32), as presented in Fig. 2F . The size of variant types of cells was labeled, and the density of cell clusters was marked blue and red. Both cell size and density were correlated to the Diffusion Dictionary detected with diffusion basis spectrum imaging (DBSI). Section title: Ex-vivo validation: compare ex-vivo MRI and IHC Educational score: 4.113393306732178 Domain: biomedical Document type: Study Language: en Specimens were collected from five fresh placentas after delivery to conduct ex vivo MRI scans. The samples were approximately 1 cm in width and length and were the entire height (thickness) of the placenta. Samples were stored at 4 °C, and within 12 h after delivery of the placenta, the specimens were embedded in a customized container filled with 2% agar. The ex vivo MRI was conducted on an 11.7 T Varian MRI scanner at 20 °C. A 2D EPI sequence was used, with TR = 1000 msec, TE = 32 msec, voxel size = 0.25 × 0.25 × 1 mm 3 , diffusion time = 16 msec, diffusion interval = 7 msec, 86 different diffusion weightings, and 5x diffusion intensity . Section title: Ex-vivo validation: compare ex-vivo MRI and IHC Educational score: 4.090459823608398 Domain: biomedical Document type: Study Language: en After MRI scans, the samples were bisected, fixed in 10% neutral-buffered formalin for one week, and processed into paraffin. Then, slide-mounted 5 µm histologic sections underwent immunohistochemistry with an anti-CD4 antibody (CONFIRM anti-CD4(SP35), Pre-dilute, Ventana, USA) and hematoxylin counterstain. Finally, the stained sections were scanned in a Hamamatsu NanoZoomer at 200x magnification. The details of quantification, co-registration, and correlation analysis between ex-vivo data can be found in Supplementary Material 2 Section title: Diffusion basis spectrum imaging Educational score: 4.32063102722168 Domain: biomedical Document type: Study Language: en A customized preprocessing pipeline for placental diffusion MRI data is shown in Supplementary Material 1 . In DBSI analysis 26 , the diffusion MRI data are separated into a linear combination of signals across known physiological and pathological ranges (Eq. 1 ) . By solving the linear equation, the mixture of diffusion compartments inside a single imaging voxel can be revealed. The solved linear coefficients are the diffusion basis spectrum . 1 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${S}_{k}=\mathop{\sum }\limits_{i=1}^{{N}_{{aniso}}}{f}_{i}{e}^{-\left|\vec{{b}_{k}}\right|{\lambda }_{{\perp }_{i}}}{e}^{-\left|\vec{{b}_{k}}\right|\left({\lambda }_{{\parallel }_{i}}-{\lambda }_{{\perp }_{i}}\right){cos }^{2}{\phi }_{{ik}}}+\mathop{\sum }\limits_{j=1}^{{N}_{{iso}}}{f}_{j}{e}^{-\left|\vec{{b}_{k}}\right|{D}_{j}}$$\end{document} S k = ∑ i = 1 N a n i s o f i e − b k → λ ⊥ i e − b k → λ ∥ i − λ ⊥ i c o s 2 ϕ i k + ∑ j = 1 N i s o f j e − b k → D j Where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${S}_{k}$$\end{document} S k and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\vec{{b}_{k}}$$\end{document} b k ⃗ are the signal and b -value of the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${k}^{{th}}$$\end{document} k th diffusion gradient; 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Additionally, conventional diffusion tensor imaging was performed to compute the ADC. The DBSI-derived ‘restricted’ isotropic diffusion fraction ( D j ≤ 0.6 μm 2 /ms) is defined to reflect cellularity ratio in placenta. Section title: Supplementary information Educational score: 1.1572695970535278 Domain: biomedical Document type: Other Language: en Supplementary Information | Review | biomedical | en | 0.999996 |
PMC11698692 | Section title: Introduction Educational score: 4.332704544067383 Domain: biomedical Document type: Study Language: en Chronic otitis media (COM), a common condition in otorhinolaryngology, is characterized by chronic, intermittent, or persistent discharge through a perforated tympanic membrane (TM) . COM is clinically characterized as an inflammatory condition associated with otorrhoea and tympanic membrane perforation in some cases . In COM, tympanic membrane perforation and ossicular chain erosion cause defective middle ear function leading to hearing loss. The proposed mechanism for erosion is chronic middle ear inflammation resulting from the overproduction of cytokines TNF alpha, interleukin-2, fibroblast growth factor, and platelet-derived growth factor, which promote hypervascularization, osteoclast activation, and bone resorption causing ossicular damage . Section title: Introduction Educational score: 4.035910606384277 Domain: biomedical Document type: Review Language: en The human ear can recognize sound waves in a frequency range of 20-20,000 Hz. Human speech frequencies are in the range of 500-4000 Hz, and the decibel level for a normal conversation is between 45 and 60 dB. The degree of hearing loss depends on the size of perforation in the tympanic membrane, ossicular chain, and inner ear. Pure tone audiometry helps to identify hearing thresholds of an individual based on the intensity and pitch of the sound waves. Since hearing loss is the most common complication associated with COM, which affects day-to-day activity and the quality of life of an individual, an attempt is made to analyze the hearing loss by audiometry in patients with COM . The goals of any surgery for COM include the creation of a dry, safe ear and the maximal preservation or restoration of hearing . The management of chronic otitis media, with or without cholesteatoma, is cortical mastoidectomy with TM perforation repair and/or ossicular chain repair, which is considered the treatment of choice for active chronic otitis media . Section title: Introduction Educational score: 4.0689239501953125 Domain: biomedical Document type: Study Language: en The aim of this study was to evaluate the postoperative audiological outcomes in middle-aged patients compared to younger patients who underwent tympanoplasty with mastoidectomy via post-auricular approach for the treatment of COM. Additionally, we compared these postoperative results with those of younger patients, providing insights into the effectiveness and safety of the procedure across different age groups. Section title: Materials and methods Educational score: 4.128205299377441 Domain: biomedical Document type: Study Language: en This study was conducted at the Department of Otorhinolaryngology, Jawaharlal Nehru Medical College and Hospital, Aligarh Muslim University, Aligarh, after obtaining ethical clearance from the Institutional Ethics Committee . A total of 70 patients, admitted in wards from August 2017 to January 2019, suffering from chronic otitis media with or without cholesteatoma who underwent tympanoplasty with mastoidectomy were included. The patients were divided into two groups: Group A (middle-aged COM group) that included patients 41 to 60 years of age and Group B (younger COM group) with patients 21 to 40 years of age. The sample size was calculated using the formula, n = 2(SD) 2 (Zα+ Zβ) 2 /d 2 , for comparison of means (audiological gain) between two groups (middle-aged COM group and younger COM group). Based on this calculation, the sample size was determined to be 35 in each group. Here, the pooled standard deviation (SD) was taken as 3.10 from a previous study, Zα was 1.96 (corresponding to a 95% confidence interval), Zβ was 0.84 (indicating 80% power), and the minimum detectable difference (d) was 2 dB based on previous research findings . The study aimed to compare the audiological gain between the two groups, i.e., the middle-aged COM group and the younger COM group. All the patients were subjected to detailed history taking, a general as well as systemic examination, which included clinical examination of the ear, nose, and throat, and a complete otological evaluation done to assess the exact nature and extent of the disease. Section title: Materials and methods Educational score: 2.023653507232666 Domain: biomedical Document type: Study Language: en Inclusion and exclusion criteria Section title: Materials and methods Educational score: 3.4758517742156982 Domain: biomedical Document type: Study Language: en Patients with chronic otitis media with isolated conductive hearing loss undergoing tympanoplasty with mastoidectomy, patients between 21 to 60 years of age, and patients with appropriate cochlear reserve were included in the study. Patients with medical contraindications to surgery, COM with intracranial complications, and cases requiring revision surgery for residual disease were excluded. Section title: Materials and methods Educational score: 0.8652209043502808 Domain: biomedical Document type: Other Language: en Follow-up Section title: Materials and methods Educational score: 2.8175668716430664 Domain: biomedical Document type: Study Language: en Patients were followed up for a period of approximately six to nine months to assess postoperative complications and disease recurrence. Audiological status was evaluated at three, six, and nine months after surgery. Section title: Materials and methods Educational score: 1.7572020292282104 Domain: biomedical Document type: Study Language: en Comparisons between middle-aged and younger COM groups Section title: Materials and methods Educational score: 4.078390598297119 Domain: biomedical Document type: Study Language: en To compare the postoperative results of tympanoplasty with mastoidectomy between middle-aged and younger-aged COM groups, we compared the hearing improvements in the two COM groups. We calculated mean hearing levels by averaging the hearing thresholds at 500, 1000, 2000 and 4000 Hz (to yield the four-tone pure tone average) after three, six, and nine months of surgery. Then we compared the preoperative and postoperative air-bone (AB) gaps between the middle-aged and younger COM groups. Additionally, we compared postoperative complications between the two groups. Postoperative results of tympanoplasty with mastoidectomy were evaluated in terms of average hearing gain. Section title: Materials and methods Educational score: 1.4600969552993774 Domain: biomedical Document type: Other Language: en Statistical analysis Section title: Materials and methods Educational score: 2.9356563091278076 Domain: biomedical Document type: Study Language: en Data were analyzed using IBM SPSS Statistics, version 20 (IBM Corp., Armonk, NY). Continuous variables were expressed as means ± standard deviations, and categorical variables were expressed as frequencies and percentages. The unpaired t-test and chi-square test were used to compare the outcomes between the two groups. A p-value of <0.05 was considered statistically significant . Section title: Results Educational score: 2.7162487506866455 Domain: biomedical Document type: Study Language: en The demographic profile of the participants is summarized in Table 1 . The mean age was 48.23 years (SD = 5) in the middle-aged group and 29.66 years (SD = 5) in the younger group. The groups were comparable in terms of gender distribution, with a slight predominance of males in both groups. Rural participants were more prevalent in both groups. In the middle-aged group, there were 19 male and 16 female patients, with a male-female ratio of 1.19:1. In the younger age group, there were 21 male and 14 female patients, with a male-to-female ratio of 1.5:1 (Table 1 ). Section title: Results Educational score: 3.8304522037506104 Domain: biomedical Document type: Study Language: en Ear discharge and decreased hearing were the most common symptoms in both groups. Specifically, ear discharge was reported in 82.86% of middle-aged patients and 91.43% of younger patients, while decreased hearing was reported in 74.28% of middle-aged patients and 65.71% of younger patients. Other symptoms, such as postauricular swelling, earache, tinnitus, facial weakness, dizziness, and fever, were less frequently observed and showed no statistically significant differences between the groups (Table 2 ). Section title: Results Educational score: 3.7237842082977295 Domain: biomedical Document type: Study Language: en In both middle-aged and younger patients, canal wall up mastoidectomy was more common than canal wall down mastoidectomy. However, compared to younger patients, canal wall down mastoidectomy was more common in middle-aged patients, and canal wall up mastoidectomy was more common in younger patients compared to middle-aged patients. The difference in mastoidectomy procedures was not statistically significant, with a p-value of 0.192 (Table 3 ). Section title: Results Educational score: 2.9890453815460205 Domain: biomedical Document type: Study Language: en The postoperative audiological gain in middle-aged patients after three, six, and nine months is detailed in Table 4 . Section title: Results Educational score: 4.098689079284668 Domain: biomedical Document type: Study Language: en The postoperative audiological gain in younger patients after three, six, and nine months is presented in Table 5 . The middle-aged patients showed a larger preoperative AB gap (32.36 ± 3.36) than the younger patients (27.90 ± 2.43). This difference was statistically significant with a p-value of <0.00001. Section title: Results Educational score: 4.075458526611328 Domain: biomedical Document type: Study Language: en After three, six, and nine months post-surgery, the overall improvement in the AB gap (mean audiological gain) was higher in middle-aged patients compared to younger patients. However, the difference in the mean audiological gain was not statistically significant, with p-values at 0.3034, 0.3271, and 0.2923, respectively. The audiological gain demonstrated a slight decrease over time in both groups. Section title: Discussion Educational score: 4.040196895599365 Domain: biomedical Document type: Study Language: en In this study, we aimed to compare the outcomes of tympanoplasty with mastoidectomy in middle-aged and younger patients diagnosed with chronic otitis media, with or without cholesteatoma. The primary focus was on evaluating differences in audiological improvement between the two age groups. Section title: Discussion Educational score: 2.925433874130249 Domain: biomedical Document type: Study Language: en In our study, the majority of cases were from rural areas and belonged to low socio-economic strata. This is in concurrence with the study results of Islam et al. who also found a majority of this disease prevalence in rural areas . Rao et al. found that the peak incidence of the disease was between 21 and 30 years of age (45.2%) . Section title: Discussion Educational score: 3.885794162750244 Domain: biomedical Document type: Study Language: en The clinical symptoms, particularly, ear discharge and decreased hearing were the most common presentations in both groups. The high prevalence of ear discharge in both groups (82.86% in middle-aged patients and 91.43% in younger patients) highlights the chronic nature of the disease and its impact on quality of life. These findings are consistent with previous studies that identified ear discharge as a primary symptom of COM. Despite the slight difference in percentages, the statistical analysis showed no significant difference between the groups . Section title: Discussion Educational score: 4.115711212158203 Domain: biomedical Document type: Study Language: en The overall postoperative mean audiological gain in the middle-aged patients was 7.59 ± 3.28 dB at three months, 7.32 ± 3.42 dB at six months, and 7.38 ± 3.43 dB at nine months; in younger patients, it was 7.23 ± 2.53 dB at three months, 6.97 ± 2.77 dB at six months, and 6.90 ± 2.86 dB at nine months. Although the postoperative mean audiological gain was slight more in the middle-aged patients, the difference was not statistically significant with p-values of 0.30, 0.33, and 0.29 at three, six, and nine months, respectively. This is in concurrence with the study of Ahn et al. who also found that there was no significant difference in the improvement of the AB gap between the two groups, although both preoperative and postoperative AB gaps in the elderly patients were significantly larger than those in the younger patients . Section title: Discussion Educational score: 4.003762245178223 Domain: biomedical Document type: Study Language: en In both groups, the postoperative mean audiological gain was more in those patients who underwent tympanoplasty with canal wall up mastoidectomy. The results were consistent with those of Hirsch et al., who reported better hearing outcomes with canal wall up mastoidectomy . Albu et al. also demonstrated that postoperative auditory results significantly improved in canal wall up mastoidectomy cases when compared to open technique cases . Wetmore et al. found in a series of 161 patients with cholesteatoma that the mean pure tone average remained unchanged after surgery. They concluded that canal wall up and canal wall down mastoidectomy procedures had no influence on the hearing outcome . Section title: Discussion Educational score: 3.4677255153656006 Domain: biomedical Document type: Review Language: en The results of hearing reported in the literature are contrasting. In fact, Paparella et al. reported better results with canal wall up mastoidectomy . Karmarkar et al. did not find significant differences between canal wall up and canal wall down mastoidectomy procedures . Tos and Lau were unable to demonstrate a significant difference in the hearing outcomes of canal wall up and canal wall down mastoidectomies . Section title: Discussion Educational score: 4.093106269836426 Domain: biomedical Document type: Study Language: en Audiological improvement, measured as the mean audiological gain, demonstrated a slight decrease over time in both groups. In younger patients, the mean audiological gain reduced from 7.23 dB at three months to 6.90 dB at nine months. In middle-aged patients, the mean audiological gain decreased from 7.59 dB at three months to 7.38 dB at nine months. These findings suggest that while initial improvements in hearing are achieved, maintaining these gains over time can be challenging. Section title: Discussion Educational score: 4.062291622161865 Domain: biomedical Document type: Study Language: en The research highlighted that patients aged 21-40 years exhibited the best outcomes in terms of graft uptake and hearing improvement. In contrast, patients younger than 20 years and older than 40 years experienced poorer outcomes. This trend aligns with previous studies that also noted age as a pivotal factor influencing tympanoplasty results. For instance, Tos and Lau reported that the youngest patients, particularly those under 10 years, demonstrated better results in dry ear conditions compared to older patients with discharging ears. Similarly, Emmett found that age significantly affected the success rate of tympanoplasty, with older patients generally having poorer outcomes. However, in our study, we did not find any significant difference in audiological outcomes . Section title: Discussion Educational score: 4.068233489990234 Domain: biomedical Document type: Study Language: en This study has certain limitations that should be considered. Firstly, the sample size was relatively small, which may limit the generalizability of the findings to a broader population. Additionally, the postoperative follow-up period was short, restricting the ability to assess long-term audiological outcomes and potential complications. Future studies with larger sample sizes and extended follow-up durations are recommended to provide more robust and comprehensive insights into the audiological outcomes of tympanoplasty with mastoidectomy in middle-aged and younger patients with chronic otitis media. Section title: Conclusions Educational score: 4.121740341186523 Domain: biomedical Document type: Study Language: en Middle-aged patients with COM showed a significantly larger preoperative AB gap than younger patients. Audiological improvement, measured as the mean audiological gain, demonstrated a slight decrease over time in both groups. However, there was no significant difference in the improvement of the AB gap between middle-aged and younger patients. These findings suggest that tympanoplasty with mastoidectomy is an equally effective surgical intervention for improving hearing outcomes in both age groups, irrespective of the initial AB gap. Further studies with larger sample sizes and longer follow-up periods are needed to validate these results and explore additional factors that may influence long-term audiological outcomes. | Study | biomedical | en | 0.999998 |
PMC11698696 | Section title: Introduction Educational score: 2.360596179962158 Domain: biomedical Document type: Other Language: en With increased national attention on senseless acts of discrimination, hate, and racism across the USA, most medical schools have renewed efforts to reexamine their curricula for disparities and bias . These efforts generally include building awareness with discussions around race and gender within the context of medicine, along with increasing faculty training. Although some of these efforts are initiated by the administration or faculty, many are student-driven . This corresponds to a general trend where students are successfully taking on prominent roles in initiatives in medical education, especially in the areas of wellness, public health emergencies, diversity, inclusion, and the transition to residency . Section title: Introduction Educational score: 3.8479769229888916 Domain: biomedical Document type: Review Language: en As students take on more leadership roles, collaborative efforts between faculty and students are becoming increasingly commonplace . Student involvement in medical education is particularly fruitful as medical students are highly motivated and can provide a unique perspective often not apparent to medical educators . Moreover, faculty working collaboratively with students allows for a better learning environment as students help the College of Medicine modify the curriculum and extracurricular activities to stay up to date with the evolving culture of medicine . Medical students are eager and interested in engaging in the transformation and innovation of medical education; however, their voices are underrepresented in the medical education scholarship . In a commentary from two medical student leaders who summarized student-led initiatives in medical education, they concluded that “…we should move beyond simple engagement and instead empower trainees to lead and co-create initiatives that can ultimately benefit the entire medical education community” . Section title: Introduction Educational score: 1.833448052406311 Domain: other Document type: Other Language: en Co-leadership models have been used in a variety of ways in healthcare, social services, training, and education . Despite co-leadership being used in education sectors, literature is sparse on co-leadership models involving faculty and students. Fall and Menendez presented advantages to co-leadership which include learning different ways to navigate an issue, role modeling of behaviors, and emotional safety . For co-leadership models to succeed, potential pitfalls to be mindful of include negative interactions between the co-leaders (e.g., competition), conflict resolution, and delineation of responsibilities . As institutions include more student engagement into curricular and pedagogical approaches, it is important to consider student-faculty partnerships and outline the benefits and strategies for successful co-leadership relationships. Some studies have shown positive outcomes of co-leadership such as improving decision-making, increasing gender parity , innovation, and organizational outcomes . Section title: Introduction Educational score: 3.6553966999053955 Domain: biomedical Document type: Study Language: en In this article, we describe how a co-leadership dyad involving a faculty member and medical student was used to advance inclusion in medical education. In this model, of co-leadership, a faculty member and a medical student work together as equal co-chairs. This model was chosen because it brought together faculty and students working toward a common goal, with each co-chair bringing to the table a unique set of skills and perspectives. These diverse skills allowed the co-chairs to benefit and learn from each other. Here, we detail the structure and logistics of this co-leadership model and present not only the advantages but also the lessons learned from this faculty-student co-leadership model. Section title: Structure of the Advancing Inclusion in Medical Education (AIME) Taskforce Educational score: 1.5084084272384644 Domain: other Document type: Other Language: en At the request of the Dean of the University of Cincinnati College of Medicine (UCCOM), the Advancing Inclusion in Medical Education (AIME) Taskforce was created to address diversity, equity, and inclusion in our medical education curriculum and learning environment. Although the initial call was prompted by the death of George Floyd and the subsequent national call to address racial inequities, AIME was tasked to address inequities inclusive of all groups marginalized and historically underrepresented in medicine. Section title: Structure of the Advancing Inclusion in Medical Education (AIME) Taskforce Educational score: 2.618525743484497 Domain: biomedical Document type: Other Language: en The approach of the AIME task force was grounded in a multidirectional leadership model from its emphasis on open membership, inclusion of a co-leadership model, and empowerment of members to drive the priorities of the task force in a systematic way while preserving the autonomy of the design and process each workgroup wanted to incorporate. This structure allowed the co-leaders to pave the workgroup’s direction in a collaborative effort to reach the requested deliverables. AIME was co-chaired by an MD faculty member and a PhD staff member involved in medical education. From the taskforce of 39 members, four workgroups were formed (Preclinical Curriculum; Clinical Curriculum; Academic Success and Personal and Professional Development; and Metrics, Policies, and Procedures). Each workgroup was appointed a student and faculty co-chair. The intent of this structure was to ensure that all voices were considered as we critically reviewed our curriculum and learning experience. From our involvement in AIME, we noted that faculty brought to the table experience in leadership along with knowledge of the curriculum, while students typically had more coursework or personal experiences related to diversity, equity, and inclusion. Because of this, we found a co-leadership model to be beneficial and allow the student and faculty co-chairs to work together on equal footing. Moreover, as the task force was longitudinal, it allowed the faculty member to observe the student as they developed as a leader, incorporate feedback, and take on more responsibilities within the workgroup. Section title: Structure of the Advancing Inclusion in Medical Education (AIME) Taskforce Educational score: 1.855439305305481 Domain: biomedical Document type: Other Language: en The two principal authors (CK and DJL) were selected to co-lead the Preclinical Curriculum workgroup. The student co-chair in the Preclinical Curriculum workgroup (CK) was a first-year medical student at the time of formation of AIME. This allowed her to participate fully in the committee’s work for 2 years. Most of the other workgroups were co-chaired by a more senior student. While more senior students are more experienced, they often had scheduling challenges due to their busy clinical schedules, and eventually graduated and moved on to residency. For this reason, this article focuses on the co-leadership relationship established by the Preclinical Curriculum subcommittee. Section title: Content Analysis of Co-chair Reflections on Their Co-leadership Experience Educational score: 1.940289855003357 Domain: biomedical Document type: Study Language: en Each of the co-chairs of the Preclinical workgroup provided individual reflections of their experience in the co-leadership model. Content analysis was used by the co-chair of the AIME Task Force (TP) who has experience in qualitative research methods to identify themes to this co-leadership model. The themes that emerged from this analysis were motivation, collaboration/partnership, and process. Section title: Motivation Educational score: 1.7229046821594238 Domain: other Document type: Other Language: en Both the faculty and student were motivated to join the AIME Task Force by a drive to make a difference. The student was focused on being intentional with their time in medical school to engage in meaningful work. The faculty member saw opportunities to improve the learning environment. This drive is important as it enhances their ability to be flexible and learn to compromise with each other, knowing that they’re doing so to achieve the same goal and knowing they’re both equally invested. Section title: Motivation Educational score: 1.2349246740341187 Domain: other Document type: Other Language: en Interestingly, both applied to be co-chair of a workgroup not thinking they would be selected. Student—When I started medical school, I knew I wanted to be intentional with my time. I wanted to focus on doing work that meant more to me than just lines added to a CV for residency. Faculty—I joined AIME because I saw places where our curriculum could do more to help underrepresented students feel more comfortable and welcome. I also joined AIME because I saw things that were being done in other institutions that were not helpful, and in fact harmful, so I wanted to ensure that we did not make the same mistakes. Section title: Collaboration/Partnership Educational score: 1.302430272102356 Domain: other Document type: Other Language: en The effectiveness of this co-leadership model is really driven by shared collaboration and partnership. The student had pre-conceived notions of how their role would look on the workgroup based on prior experience in research where the faculty member sets the direction while the student is assigned logistical tasks. On the other hand, the faculty member had no preset goals or ideas on how to approach the complex issues that the AIME Task Force would be identifying in their recommendations. The faculty member took a participatory approach to the workgroup—inviting the student leader’s thoughts on how to approach the workgroup meetings and recognizing their positionality and lenses they bring to the collaboration and the work of the AIME Task Force. The faculty member is an experienced educator who has led many other committees before and saw this as an opportunity for the student to lead, with the faculty member taking on more of a supportive role. This co-leadership model was approached with a willingness to share the workload as equally as possible and support the other member when schedules were heavier. Student—I was amazed, however, once I started working with [faculty co-chair]. From our first meeting, he asked me how I thought the subgroup would best serve its purpose and how we should conduct our meetings. At the end of the first co-chair meeting, he asked me if I would like to lead our subgroup meetings. Faculty—When we started our work, I didn’t have a plan to transition this into a co-mentorship or reverse-mentorship structure. [student co-chair] enthusiastically stepped in and started taking responsibility for the work of the committee, its organization, how it ran, etc., so it was easy for me to step back and let her take more of a role in directing the group. Student—After that, he let me lead all the meetings while he took on tasks such as scheduling meetings, taking notes, sending follow-up emails. Again, I never asked him to do that and I offered to take it off his plate but he’d remind me that he’d already had the opportunity to lead groups before and this was instead a good learning opportunity for me. Section title: Process Educational score: 1.2969061136245728 Domain: other Document type: Other Language: en The co-chairs of the workgroup emphasized planning, debriefing, and clear communication to achieve outcomes in their workgroup. Planning involved the co-chairs meeting prior to the meeting with the full workgroup to set an agenda and prepare to-do lists ahead of the meeting. The faculty co-chair made sure that the student would know all the individuals who would be present in the room. The student co-chair then led the meeting with the larger workgroup while the faculty co-chair listened, observed, and took notes. A debriefing meeting took place after each workgroup meeting to provide time and space for feedback and confidence building. Follow-up tasks were developed and assigned. The co-chairs also discussed any adjustments that needed to be made to facilitate the progress of the group. Lastly, the co-chairs would communicate next steps to the workgroup that incorporated feedback from the group and applied adjustments discussed during the debriefing. Importantly, the co-chairs co-signed all communications to demonstrate this shared leadership model. Faculty—For each of our subcommittee meetings, [we] met to plan how we wanted the meeting to go, what to put on the agenda, and in which order. After each meeting, we met to de-brief, summarizing what happened at our meetings, how things could have been better, and then came up with a task-list to accomplish before our next meeting. Assigning these tasks was easy, we simply divided relatively equally in some cases, and adjusted for situations where one of us was particularly busy (“Oh, you have three exams this week (or you’re directing a course this week), then I can work on creating that table, so it’s done before our next meeting.”) Student—Before our subgroup meeting, we made sure to meet and discuss our main agenda and to-do lists. The initial subgroup meeting definitely felt odd to me. I kept waiting for [faculty co-chair] to jump in and cut me off afraid I was saying something wrong or not doing a good enough job leading. Instead, he remained silent. He jumped in a few times to offer his opinion on the discussion amongst the group members but that’s about it. Afterwards, we debriefed, and he gave me his thoughts on things to keep in mind/way to improve along with encouragement that I was doing a good job leading. This was crucial in building my confidence. Section title: What We Learned from Our Experience as Student/Faculty Co-leaders Educational score: 1.1947635412216187 Domain: other Document type: Other Language: en While co-chairing the Preclinical Curriculum workgroup, the principal authors (CK and DJL) identified parameters that were essential for their relationship to be fruitful for both members as co-leaders of the committee, and for the advancement of the deliverables of the committee. Section title: What We Learned from Our Experience as Student/Faculty Co-leaders Educational score: 2.2462942600250244 Domain: other Document type: Other Language: en These experiences are listed below and summarized in Table 1 and outlined in a flow chart in Fig. 1 . Some of these insights are intuitive yet nevertheless significant. Both co-chairs must be passionate about the workgroup and committed to the importance of their mission. This ensures prompt completion of work for the workgroup and encourages the team to feel as if they are making a difference, thereby increasing motivation. For this to happen, both co-chairs must reflect on their current schedule and confirm they can appropriately dedicate time to their workgroup. This is necessary to ensure the teamwork is productive and allow both parties to get the most out of the relationship. Open communication between the two co-chairs sets the stage for success. This starts with something as minute as agreeing upon a preferred method of communication and prioritizing responding to each other to continue the momentum of the work. It also entails taking the time to discuss their respective goals and ensure alignment. The co-chairs set the tone for the work accomplished by the workgroup. Hence, valuable time and energy is wasted if the agendas of the co-chairs do not align from the beginning. Moreover, misaligned missions can lead to disagreements and a strained relationship between the co-chairs as time progresses. Periodically checking-in with each other to discuss and assign tasks which need to be accomplished closes the loop of communication and minimizes the chance of miscommunication. Shared goals are essential. In most cases, faculty, especially senior faculty, have had numerous previous opportunities to serve in leadership positions. Therefore, chairing a workgroup may not be as much of a career priority for promotion or recognition. This allows the flexibility to step back and become a mentor to the student in the process of leadership, such as organizing meeting agenda items, running meetings, and following up to achieve the most benefit from the meeting. In return, the faculty member can appreciate things from a student perspective, such as ways to identify and address disparities. From the student’s perspective, co-chairing with a faculty member reduces the stress that comes with leading a group. For example, some stressors removed include the logistics of coordinating everyone’s schedule for meetings, learning and developing efficient agendas for each meeting, and attempting to outwardly seek feedback on leadership. With some of these barriers minimized or even removed, the focus can be on the task at hand, allowing for significantly more personal growth. It is critical to use a “flipped” format of the standard student-faculty co-chair relationship. There is an inherent power differential that exists within most faculty-student collaborations. The faculty member generally dictates the direction of the group, and the student goes along with the decisions made by the faculty . We revised this model. Before workgroup meetings, the co-chairs met to agree on agenda items and how to navigate difficult discussions. However, during the actual workgroup meetings, it was critical for the student to lead the discussion. In our case, the faculty member contributed to the content of the discussion as any other member but stayed in the background unless certain topics came up in the discussion where the faculty co-chair had more experience or insight. For this model to work and allow the student to focus on leading, the faculty member must be agreeable to taking on “supportive roles” such as keeping meeting notes or generating initial drafts of documents. This flipped leadership model extended to outward-facing presentations as well. For example, when our workgroup presented to the larger AIME Taskforce, curriculum governance committee, or the entire student body, it was important to have the student co-chair deliver the presentation. As with the workgroup meetings, the co-chairs met briefly beforehand to agree upon the content of the presentation. This not only provided unique opportunities for growth, but gave a clear signal that students are significant stakeholders in the process. It also allowed the student to get feedback from the faculty member on their public speaking and communication skills. Even the little details are significant. As communications sent by co-chairs were always a collaborative effort, they were signed by both. This may seem trivial, but messages signed by both co-chairs (even in situations where authorship of the content was from one co-chair) provided a clear signal to the workgroup and the larger taskforce that leadership of the workgroup was a joint effort. Language and environment were also essential. The faculty member went out of their way to ensure the student felt comfortable in new and unfamiliar meeting settings. Before meetings with administrators unfamiliar to the student, the faculty member and the student would meet to discuss their goals for the meeting and the role of each person that would be present at the meeting. During a meeting, it was important for the faculty member to ask the student if they had anything to add to the conversation. This created a comfortable way for the student leader to speak up or request clarification. Most importantly, mutual respect was the backbone of this faculty-student co-chair relationship. Leading a workgroup of this importance while either teaching or being a student at a medical school is not easy. This is where it becomes important for each co-chair to take initiative and understand each other’s timelines and be willing to take over some of the work if one chair had a period of increasing responsibilities outside the workgroup. This approach maintained workgroup momentum and further enhanced the co-leadership relationship. Table 1 Examples of the key factors to success in a student-faculty co-director relationship Clear communication on agenda (Shared Goals and Communication) Meet a few times in the beginning to talk through ideas and make a list of short- and long-term goals to track progress and maintain momentum Faculty member allowing student to take lead (Flipped Leadership Model) The student oversees running all the workgroup meetings and making presentations regarding progress to the larger taskforce or the student body/administration Faculty and student meet before meetings to discuss salient points, and student checks-in frequently post-meetings to gain feedback on leadership Faculty member helping or taking lead on mundane administrative tasks (Flipped Leadership Model) To decrease the amount of administrative work for the student, the faculty member helps plan meetings, respond to emails, and organize logistics Student takes a lead in driving the agenda of the committee (Flipped Leadership Model) Student is more active in presenting ideas for accomplishing the tasks of the committee and explaining to the faculty co-chair the reasoning behind the direction of the committee Presenting a united front (Collaboration and Importance of the Little Things) Both co-chairs sign all emails, and both co-chairs are invited to attend all meetings Developing a comfortable environment (Mentoring for Leadership; Providing Safety) In meetings with administrators or other faculty members, it is easy for the student to feel overwhelmed. Obvious vocal support from the faculty co-chair in ways of asking for opinions or asking student to chime in allows the student to feel more empowered to speak up Mutual respect (Communication and Mutual Respect) Continuous appreciation and respect for each other in ways of stepping in when the student knows the faculty member has a busy week or vice versa allows the relationship to truly flourish and for both individuals to feel valued Fig. 1 Key ingredients for co-leadership. Figure created using Venngage software Section title: Conclusions Educational score: 1.9207381010055542 Domain: biomedical Document type: Other Language: en The workgroup co-chair organization of AIME inherently provided an avenue toward co-leadership and collaboration between students and faculty. As we have discovered, co-leadership between faculty and students can result in mentoring opportunities within the organization of groups involved in working on initiatives in medical education. This creates a powerful experience for both the student and faculty member, as both have something to contribute to and learn from the experience, especially in a longitudinal manner. Moreover, it provides ownership for all involved and gives natural outward projection that the resulting initiative is indeed a collaborative effort. | Other | biomedical | en | 0.999998 |
PMC11698704 | Section title: Introduction Educational score: 3.4709665775299072 Domain: biomedical Document type: Other Language: en The use of multiple-choice questions (MCQs) to assess higher order learning is standard practice for assessing clinical knowledge in the health professions . However, the creation of such questions is not straightforward, often requiring ‘Item Writing Workshops’ to train staff in the creation of clinical scenarios for such questions . There is a need to expand the use of higher order MCQs, beyond the evaluation of clinical scenarios and into medical science education more generally, where assessments of ‘higher order learning’ may be currently given in the form of written coursework such as essays and dissertations. These assessments tend to show limited coverage of the curriculum and are vulnerable to a number of forms of misconduct, such as plagiarism , outsourcing to commercial writers , and the use of Chatbot AI tools such as ChatGPT . Section title: Introduction Educational score: 1.9665523767471313 Domain: other Document type: Other Language: en Many authors have written guidance for the use of MCQs to assess higher order learning, and these were recently reviewed into a set of guidance principles for educators wishing to write their own questions . A key feature of MCQs that assess higher-order learning is the use of problem-type scenarios, which the learner then solves, rather than the recall of a standalone fact . The scenario should contain a lot of information, as is the case in real-world problems, and the test-taker has to critically appraise the information to identify key relevant features . Another feature of MCQs which assess higher order learning is the use of ‘assumed knowledge’; i.e., the student is required to have specific subject knowledge or skills which are missing from the problem scenario and thus can act as a cognitive bridge between the problem/question and the answer options . Students who do not have this knowledge will not be able to answer the question. Section title: Introduction Educational score: 1.0728225708007812 Domain: other Document type: Other Language: en Higher order learning is usually defined with reference to Bloom’s taxonomy or some other hierarchy (e.g. [ 1 , 2 , 9 , 11 – 14 ]). Bloom’s taxonomy is usually presented as a hierarchy of verbs for the creation of learning outcomes, with the principle that outcomes created using verbs from the base of the hierarchy (e.g. list, recall) are ‘lower order’ learning, whereas verbs at the higher end of the taxonomy (e.g. ‘evaluate’, ‘justify’) represent ‘higher order learning’ . However, Bloom’s taxonomy has faced many decades of criticism from multiple angles, including a concern that it cannot meaningfully identify ‘higher order learning’ [ 18 – 21 ], and recent studies in the UK and the USA have shown that the presentation of Bloom’s taxonomy is remarkably inconsistent between universities and other sources. That is, one presentation of Bloom’s may place a verb at the very bottom of the taxonomy, whereas another will place that same verb at the very top . Section title: Introduction Educational score: 3.6304080486297607 Domain: other Document type: Study Language: en Despite these criticisms, it is still common for Bloom’s taxonomy to be used as the reference point when defining higher order assessment items. One approach is to ask participants (e.g. academics or students) to assign assessment items to the relevant level of Bloom’s taxonomy, or to identify relevant action verbs when writing the items . These sorts of validations were undertaken in the studies which were reviewed to develop the higher-order item writing guidance being tested here . However, this sort of validation normally requires collapsing the six tiers of the taxonomy into just two or three, and then asking subject experts to make subjective ratings about the level of learning which is being assessed by the question. Even then it has been repeatedly shown that academics find it difficult to do this reliably (e.g. the ratings of an assessment item as ‘higher’ or ‘lower order’ will vary between academics) [ 24 – 27 ]. Other taxonomies of learning have also been used to classify learning by cognitive level; for example, the ‘Structure of Observed Learning Outcomes’ (SOLO) Taxonomy, popular in higher education in the UK, has been used to design MCQs which aim at assessing ‘higher order’ learning , while in North America, clinical question banks may be classified into 1st, 2nd, and 3rd orders, with 1st-order questions assessing factual recall, while 3rd-order questions require critical thinking and problem-solving . Again though, while there are guidelines for the creation of questions which map to these levels, there is a paucity of objective evidence showing that the assigning of questions to these levels is reliable. Section title: Introduction Educational score: 2.4771220684051514 Domain: other Document type: Study Language: en An alternate approach is to generate objective data about the ability of students to correctly answer the questions, dependent on their level of expertise, on the basis that students with existing lower order knowledge will find it easier to answer the higher-order questions than subject-novices who do not have that knowledge. These hypotheses are supported by some prior research (e.g. ), but still the majority of research in this area appears to rely on subjective ratings of question difficulty. Here then, we tested guidance designed to help educators write higher-order MCQs , by generating objective data on the ability of subject novices vs experts to answer questions which had been written using the guidance. Section title: Guidance for the Creation of Higher Order MCQs Educational score: 3.0526840686798096 Domain: other Document type: Other Language: en This guidance has been published previously, in a detailed form , based on a number of papers describing the use of MCQs to assess higher order learning [ 10 , 12 , 14 , 31 – 46 ]. A summary of the guidelines is shown in Table 1 . Examples of higher order questions written using the guidance, and their lower order equivalents, are given in ESM Appendix 1 . Table 1 Summary of principles for the creation of higher-order bridge MCQs. Derived from • Start with a lower order MCQ that assesses factual knowledge. Identify an existing question, or write a simple MCQ that tests factual knowledge • Problem scenario . (Re)write the question stem into a problem that needs to be solved rather than a question to be answered. One simple way to do this is to write a scenario that describes the correct answer, but in non-technical terms • Identify assumed knowledge (bridge). The student should have some prior knowledge in order to answer the question, without which the question cannot be answered. This prior knowledge must be relevant to interpreting both the question and the answer options. One way to identify assumed knowledge is to identify a sequence of steps/knowledge needed to solve a problem, and take out those in the middle • Use common language . Using everyday language, as a more authentic problem presentation. Avoid technical terms, as these can signpost correct answers. Where technical terms are unavoidable, try to put them in only one of either the scenario, or the answer options • Use active answers . Having the answer options as actions, or describing actions, makes them less likely to be a list of facts • Use annotated images. (optional) • Number of answers . Increase these to ~ 8, to allow for more granularity in the answer options Section title: Guidance for the Creation of Higher Order MCQs Educational score: 1.9779882431030273 Domain: other Document type: Study Language: en We conducted two different sets of experiments to compare questions written using the guidance with their lower order counterparts. A summary of the key differences between these experiments is given in Table 2 . Table 2 Summary of the two sets of experiments conducted here Feature Experiment 1 Experiment 2 Aim Pilot proof of principle Full testing of guidance Participants Novices only Novices vs experts Lower order questions Author generated Existing questions from textbooks Payment Flat fee Flat fee plus bonus per question Answer options Different between higher order Consistent between higher order and lower order Subject Neuroscience Genetics Section title: Guidance for the Creation of Higher Order MCQs Educational score: 2.0539209842681885 Domain: biomedical Document type: Study Language: en All studies were carried out using Qualtrics surveys with student participants recruited via the online labour market Prolific ( www.Prolific.com ). The fee was at an estimated hourly rate of £8, advised by Prolific to be a ‘good’ rate at the time of the study. Participants were screened into expert or novice groups on the basis of the subjects being studied at university. The full list of subjects which were used to screen participants for each study is shown in ESM Appendix 1 . Before beginning the study, all participants were given information about their data protection rights, their right to withdraw at any time, and a contact email for any questions. We were not aware of any similar studies in the literature which might give us a reasonable expectation of the possible sizes of any differences between the experimental groups, and so we were unable to undertake a meaningful power analysis and sample size calculation. Thus, the sample sizes are based on the experience of the authors. Section title: Guidance for the Creation of Higher Order MCQs Educational score: 1.151376724243164 Domain: biomedical Document type: Other Language: en Ethical Approval. Section title: Guidance for the Creation of Higher Order MCQs Educational score: 0.7653018832206726 Domain: biomedical Document type: Other Language: en Both experiments were approved by the ethics committee of the Swansea University Medical School ref SUMS RESC 2022-0042A. Section title: Experiment 1. Novices Only, Proof of Principle Educational score: 2.098161220550537 Domain: other Document type: Study Language: en An initial study was conducted to determine whether subject matter novices could meaningfully answer lower order questions, under time-limited conditions. In this same experiment, we then evaluated whether this ability would be reduced when the questions were rewritten using the guidance from Table 1 . Questions were tested on novice students, meaning they were studying subjects unrelated to the subject matter of the questions (neuroscience). Each question was asked in both higher and lower-order formats, and under both closed book and open book conditions. Section title: Procedure Educational score: 2.178875207901001 Domain: other Document type: Study Language: en We evaluated the performance of the questions under two conditions: ‘closed book’ wherein participants were asked to try and answer the questions without referral to any other sources, and then an ‘open book’ condition, wherein students were encouraged to ‘cheat’ by any means, for example by using Google or Alexa. Participants were asked to ‘cheat’ rather than to use ‘an open book condition’ on the basis that this would be more familiar terminology and so easier for the participants to correctly follow the instructions. To minimise confusion in the instructions for participants, each participant was asked to answer in only one condition (closed or open book), but was asked questions from both formats (lower order or higher order), although the format difference was not explained. Thus, a participant only saw one version of an individual question. The same questions were asked, in the same order, in each group, but in different formats (higher order or lower order). Therefore, the experimental groups were as follows: Higher-lower (closed book) Lower-higher (closed book) Higher-lower (open book) Lower-higher (open book) Section title: Procedure Educational score: 2.074012279510498 Domain: biomedical Document type: Study Language: en Thus, groups 1 and 3 would start with Q1 in a higher-order format, followed by Q2 in a lower-order format, then Q3 in a higher order format, and so on. Groups 2 and 4 would start with Q1 in a lower-order format, Q2 in a higher order format, and so on. Dropout and motivation were a concern, since it seemed likely that participants would be unable to answer the questions, and so the study was conducted in two parts: an initial proof-of-principle pilot evaluated the performance of 12 questions, and then the second part evaluated the performance of 5 further questions. Twelve participants were recruited to each group, except for group 3 which had 13 participants in the initial pilot, due to a technical error. The tasks on Prolific were set so that any one participant could only be recruited to one study. Section title: Procedure Educational score: 1.4955312013626099 Domain: other Document type: Study Language: en The task was advertised on Prolific as ‘A Study about University Assessment Methods’. Participants were given the instructions shown in Fig. 1 . Fig. 1 Instructions given to participants in A the closed book condition and B the open book condition experiment of Experiment 1 Section title: Procedure Educational score: 1.9134701490402222 Domain: biomedical Document type: Study Language: en The participants were then given a maximum of 90 s to answer each question, after which the instrument automatically forwarded on to the next question. At the end of the survey, the purpose of the study was explained in more detail and those who had participated in the open-book group were asked what methods they had used. Section title: Experiment 2. Novice vs Expert, Testing of Full Guidance Educational score: 3.229518175125122 Domain: other Document type: Study Language: en The first experiment used both lower and higher order questions written by the authors, which potentially leads to a conflict when we also designed the research. Experiment 2 was designed to test the guidance in a more general context that reflects the practical application of the guidance, by starting with lower-order questions that had not been written by the authors, but which subject novices could obtain the correct answer through simple Googling. These questions were identified as described below, and then rewritten by the authors following the guidance in Table 1 . We hypothesised that, once rewritten subject experts would still be able to answer the questions, but novices would not, even in the open book condition. In Experiment 1, participants were also not provided with any specific motivation to find the correct answer in the open book condition. We did not want participants to simply give up, especially since this seemed more likely for novices and so could artificially bias the data. This was addressed in Experiment 2 by giving participants a small financial incentive for answering correctly under the open book condition. A final difference between the two studies was that, in Experiment 1, the answer options were different between some of the lower and higher order formats of the same question, in accordance with the guidance (e.g. to make the answer options active). Here we retained the same answer options with the lower and higher order versions, including keeping the same correct answer. This was to ensure that the revised questions were assessing the same learning outcome as the original lower-order question, although it did present a challenge with utilising some aspects of the guidance (e.g., to make the answer options active, and to present them in plain language). Section title: Experiment 2. Novice vs Expert, Testing of Full Guidance Educational score: 2.34940505027771 Domain: biomedical Document type: Study Language: en A pilot study was undertaken to identify ‘lower order’ questions which novices could only answer under open-book conditions. Twenty questions were selected from the introductory chapter of a genetics textbook and from past-papers of the United Kingdom Biology A-level exam (these are the exams taken by students aged ~ 18, in part as the basis for entry to higher education). They were selected by the authors on the basis that they should be questions whose answers would be reasonably familiar to current undergraduates studying the life sciences. Section title: Experiment 2. Novice vs Expert, Testing of Full Guidance Educational score: 1.6410791873931885 Domain: other Document type: Study Language: en Participants were then given the instructions shown in Fig. 2 . Fig. 2 Instructions given to all participants at A the beginning (closed book) and B halfway (the open book condition) of Experiment 2. For the second part of Experiment 2, only 10 questions were used, and so the bonus payments and instructions identified in section B were modified accordingly Section title: Experiment 2. Novice vs Expert, Testing of Full Guidance Educational score: 1.8151463270187378 Domain: other Document type: Study Language: en Twenty participants were recruited to each of four groups. This experiment also included two attention-check questions, one in each condition. These were questions which appeared to be regular multiple-choice questions formatted in the same way as others in the study, but where the question stem included an instruction to select a specific answer. In keeping with the Prolific.co guidance on attention checks, participants who failed both attention checks by selecting the incorrect answer were not paid and their data were not included. Additional participants were then added as required. Novices, closed book Novices, open book Experts, closed book Experts, open book Section title: Experiment 2. Novice vs Expert, Testing of Full Guidance Educational score: 2.024746894836426 Domain: biomedical Document type: Study Language: en Using these pilot data, we identified questions for further development, based upon the following criteria: Large difference in performance on open book vs closed book for novices (i.e. questions in which the open book condition allowed the participants to score highly) Experts scored highly under both conditions Experts scored higher than non-subject specialists under the closed book condition, to ensure the expertise tested was not common knowledge. Section title: Experiment 2. Novice vs Expert, Testing of Full Guidance Educational score: 1.9119144678115845 Domain: biomedical Document type: Study Language: en The precise metrics for identifying questions were not formalised—each question was considered individually by both authors, and selected questions were then drafted into the higher order format using the guidance in Table 1 . Both authors drafted higher-order questions and then a final version of each question was agreed through discussion. The experiment was then repeated but with ten higher-order questions. Section title: Analysis Educational score: 2.003676652908325 Domain: biomedical Document type: Study Language: en For both experiments, analysis was undertaken by question, with the dependent variable being the percentage of participants who answered a question correctly. Specific statistical tests are identified in the relevant section of the results. Section title: Analysis Educational score: 1.808187484741211 Domain: other Document type: Study Language: en For the methods used by students in the open book condition, a simple quantitative content analysis was performed on the very brief free-text comments left by participants. Section title: Analysis Educational score: 1.6251753568649292 Domain: biomedical Document type: Study Language: en Example questions from Experiment 1 and Experiment 2 are shown in ESM Appendix 1 (the full set of questions is available upon reasonable request, from the corresponding author). Statistical analysis and figure creation were undertaken using GraphPad Prism V10 (San Diego, CA). Section title: Experiment 1 Educational score: 4.005941390991211 Domain: biomedical Document type: Study Language: en There was a clear effect of condition, where an average of 53.4% of participants were able to answer the questions in the open-book condition when the questions were written in the lower order format, compared to 18.6% when the questions where in the higher order format. In the closed book condition, an average of 24% of participants answered correctly in the lower order format with 13.2% answering correctly in the higher format. The percentage of participants able to answer each question in the lower order, open-book format was significantly higher than for every other format/condition when analysed using a two-way repeated measures ANOVA, with percentage of participants answering correctly as the dependent variable, and test format (closed book vs open book) and question format (higher order vs lower order) as the conditions. There was a significant effect of question format ( F (1, 16) = 25.03, P = 0.0002), and test format ( F (1, 16) = 14.59, P < 0.0001) and a significant interaction between the two ( F (1, 16) = 6.95, P = 0.0018). Post hoc Bonferroni tests revealed a significant difference between the lower-order, open-book condition, and all other conditions. No other significant differences were observed. The results are shown in Fig. 3 . Fig. 3 Rewriting lower order questions into higher order makes it harder for subject matter novices to answer. Different groups of participants were given the same question in two different formats, lower order and higher order, and under two different conditions, open book and closed book. Participants were able to answer the lower order questions in the open-book condition but were not able to answer the questions in the closed-book condition or when they were rewritten into the higher order format, even under the open-book condition. * P , 0.05 when compared to all other conditions by post hoc Bonferroni tests following two-way repeated measures ANOVA (see text for details) Section title: Methods Used in the Open-Book Condition Educational score: 1.274175763130188 Domain: other Document type: Other Language: en In 25 participants, 22 left comments, most very brief (the total corpus was 542 words). All 22 identified ‘searching the internet’ as their strategy, with 20/22 naming Google directly, and one asking ‘Siri’. In 22 participants, 6 identified the time limit as a factor which made it difficult to answer the questions. In 22 participants, 4 identified that there were questions that were more ‘difficult’ (the participants were not told that the questions were in two different formats). Section title: Experiment 2 Educational score: 2.089830160140991 Domain: other Document type: Study Language: en The results from Experiment 1 were clear: novices used Google to successfully answer questions written in a lower-order format, but this approach was not successful when the questions were in a higher-order format. However, the design of the study contained some potential confounds; (1) the participants had no obvious motivation to try and answer correctly. This was potentially more significant in the higher order condition due to the extra work required to successfully answer the question, and the increased length and complexity of the questions. (2) Both lower and higher-order questions were written by the authors. (3) There is no within-study positive control since Experiment 1 only used subject matter novices, and thus it is not clear that subject experts could still answer the higher-order questions. This is important to demonstrate that the rewritten questions remain a valid form of assessment for the subject matter content. Finally, the answer options were often completely different between the lower order and higher order question formats. Section title: Experiment 2 Educational score: 1.6211555004119873 Domain: other Document type: Study Language: en Thus, in Experiment 2, we included a within-experiment positive control. We also started with existing lower order questions, in the public domain, that had not been written by either of the authors, using the original answer options and same correct answer, but with additional answer options added. Section title: Experiment 2 Educational score: 4.0326032638549805 Domain: biomedical Document type: Study Language: en The results are shown in Fig. 4 . Novices were again able to successfully answer lower order questions by Googling the answers, an average of 73.3% answering correctly but this dropped to 23% when the questions were rewritten into a higher order format. A two-way repeated measures ANOVA was conducted, with percentage of participants answering correctly as the dependent variable, and test format (closed book vs open book) and expertise (novice vs expert) as the conditions. For lower order questions , there was a significant effect of question format ( F (1, 9) = 163.0, P < 0.0001) and expertise ( F (1, 9) = 17.09, P = 0.0025), with a significant interaction between these two conditions ( F (1, 9) = 61.91, P < 0.0001). A post hoc Bonferroni multiple comparisons test showed a significant effect of expertise in the closed-book condition but not the open-book condition . For the higher order questions , a two-way repeated measures ANOVA again showed a significant effect of question format ( F (1, 9) = 6.553, P = 0.0307) and expertise ( F (1, 9) = 18.40, P = 0.0020), but no interaction between the two conditions ( F (1, 9) = 0.2687, P = 0.6167). Fig. 4 Rewriting publicly available lower order questions into higher order questions makes it harder for novices to answer them, but experts can still answer under closed-book conditions. Different groups of participants were given the same question in two different formats, lower order and higher order, and under two different conditions, open book and closed book. Novices were able to answer the lower order questions in the open-book condition but not when the questions when rewritten into a higher order format using the guidance tested here. Experts showed good ability to answer questions under all conditions. See text for statistical analysis Section title: Experiment 2 Educational score: 1.795547604560852 Domain: other Document type: Study Language: en If the higher order questions are truly assessing higher order learning, then they should be harder, and so the percentage of experts answering them would be lower. An average of 53.3% of experts were able to answer questions in the lower order format under closed book conditions; this dropped to 40% when rewritten into the higher order format. This same comparison was 67.5% and 51.5% in the open book format. When analysed using a paired t- test, the difference between lower and higher order was significant for both the closed book and the open book condition . Section title: Discussion Educational score: 1.9326545000076294 Domain: other Document type: Study Language: en Here we conducted a validation test on guidance which is designed to help educators write higher order MCQs . When questions were written using a traditional lower order format, subject-matter novices were able to Google their way to the correct answer, to the same extent as experts, even though the novices were studying subjects unrelated to the topic. When those same questions were rewritten into a higher-order format using the guidance, subject-novices found it significantly harder to answer using Google, while experts were still able to answer the questions. These findings suggest that questions written using the summary guidance in Table 1 do indeed assess higher-order learning. The summary guidance in Table 1 is largely complementary to, and intended to be used alongside, a large body of existing literature on what makes an effective multiple-choice question, regardless of whether they assess lower or higher-order learning . Section title: Discussion Educational score: 1.7351231575012207 Domain: biomedical Document type: Study Language: en There are a number of factors and potential limitations that need to be considered when interpreting our findings. Section title: Discussion Educational score: 1.7859755754470825 Domain: other Document type: Other Language: en The guidance shown in Table 1 contains a number of different elements which combine to make the question an active, problem-solving exercise. On the basis of this study, it is not currently possible to determine which, if any, of the individual elements is the most important for ensuring that an MCQ assesses ‘higher order learning’. This is the subject of ongoing work where each element is subject to a systematic experimental appraisal. These analyses may result in a revised and condensed set of guidelines which could prioritise individual elements for the creations of higher-order MCQs. Section title: Discussion Educational score: 1.181497573852539 Domain: other Document type: Study Language: en When using online labour markets for opinion surveys, there is potentially an issue participants could simply give random, or minimal, answers , or that the participants may in fact be ‘bots’ . Here we had objective outcome measures with right and wrong answers. Although there was no incentive to answer correctly, we did see a clear and expected difference in those experimental conditions which would indicate that participants are real, valid, and following instructions (for example between subject experts and novices). Section title: Discussion Educational score: 1.8755788803100586 Domain: other Document type: Study Language: en Participants in the open-book conditions were instructed to ‘cheat’ by using whatever sources necessary. Even so, subject novices struggled to answer the higher order questions. However, it is important to be clear that this is not specifically a study of ‘cheating’ and that these higher-order questions are not ‘cheat-proof’, especially in the new era of ChatGPT, which can answer very complex problem-solving MCQs , and when cheating in online open-book exams is already high . Indeed, the ability of ChatGPT to answer questions written using these guidelines has been recently tested and ChatGPT answers almost all the questions correctly, apart from where novel, labelled images are included . However, these higher order questions should be more resilient to cheating in invigilated examinations, and offer a way to assess higher order learning in such exams. In this way, a supervised exam based on these questions would likely be more resistant to misconduct than other assessment formats which are currently used to assess higher order learning, such as essays and other asynchronous written coursework; these are open to multiple sources of misconduct such as plagiarism contract cheating and can be completed to a high standard using tools such as ChatGPT . Section title: Discussion Educational score: 1.9185214042663574 Domain: biomedical Document type: Other Language: en Guidelines developed here have been tested in only two subject areas, both of which are from human physiology and medical science. It seems reasonable to propose the guidelines could be used to test higher order learning in other subjects, including those outside of medical science education. This will require careful validation and is also the subject of future work. Section title: Discussion Educational score: 2.06038498878479 Domain: other Document type: Other Language: en In summary, we have validated guidance for item-writing, or rewriting, based on the literature for the use of MCQs to assess higher order learning. In an experimental situation, questions that were rewritten using this guidance were much more challenging to answer by simple Googling but were still answerable by students who were studying relevant subjects, although those experts found the questions harder. These findings suggest that the guidance could be used by educators and institutions to develop MCQ-based exams to assess higher order learning, to partially replace asynchronous written coursework such as essays. Section title: Supplementary Information Educational score: 1.036319375038147 Domain: other Document type: Other Language: en Below is the link to the electronic supplementary material. Supplementary file1 (DOCX 18 KB) | Other | biomedical | en | 0.999998 |
PMC11698806 | Section title: Introduction Educational score: 0.8244235515594482 Domain: other Document type: Other Language: en The American writer and political activist Helen Keller once said that “the highest result of education is tolerance” . Higher education is generally seen as a panacea for anti-immigration attitudes. Among the individual predictors of attitudes toward immigration, its positive association with liberal, pro-immigration attitudes and negative association with ethnic exclusion and national chauvinism has been so widely documented that some even concede a so-called “liberalising effect”. The actual causality of the relationship is notoriously challenging to establish, and studies that attempt this endeavour come to no definitive conclusion. Individual country studies either find no evidence for the causal link or only a small direct causal effect on individuals’ attitudes, which is not always liberalising , or a small but liberalising effect . Conversely, a study of five Western European countries demonstrates that an additional year of secondary education substantially decreases anti-immigration attitudes . These inconsistencies reveal that the role of context may be as important as differences between levels of educational attainment. If so, could these inconsistencies be related to recent changes in the social and economic environment? Section title: Introduction Educational score: 0.9715835452079773 Domain: other Document type: Other Language: en The first two decades of the third millennium were a challenging time for all European countries—the Great Recession of 2008, followed by the Eurozone crisis and the 2015 refugee crisis, altered not only the living conditions but also the very fabric of European societies. In addition to the existing idiosyncratic differences between European countries, these socioeconomic changes impacted them asymmetrically, affecting some more or differently than others. In times like these, the role of context comes to the fore—how do socioeconomic changes and regional differences affect attitudes toward immigration? Section title: Introduction Educational score: 0.7180739045143127 Domain: other Document type: Other Language: en Group threat theory proponents emphasise cultural and economic threats—real or perceived—as possible determinants of immigration attitudes . Group members may become hostile toward other groups if they feel that their national or economic interests are threatened . Indeed, recent literature investigating the impact of economic downturns reports that attitudes toward immigration became less favourable during the great recession, particularly in countries severely affected by it . Studies analysing the possible impact of the refugee crisis on attitudes toward immigration come to a less universal conclusion. Some found a polarising effect for Western Europe but no significant effect for South and Central Eastern Europe , while others found no evidence that the refugee crisis increased anti-immigration attitudes in Europe . Section title: Introduction Educational score: 1.2895220518112183 Domain: other Document type: Study Language: en More important for our undertaking is to understand how these socioeconomic changes affect established relationships, such as that between education and immigration attitudes. Studies suggest that less educated individuals from lower socioeconomic strata are more susceptible to perceptions of cultural and economic threat . Similarly, higher-educated individuals should be more immune to socioeconomic changes and less susceptible to perceived cultural or economic threats from immigrants. Velásquez and Eger , who examined the impact of the refugee crisis on the association between education and immigration attitudes in Norway, found that education has such an inoculating effect in the face of the crisis. Section title: Introduction Educational score: 0.665537416934967 Domain: other Document type: Study Language: en The literature on attitudes toward immigration emphasises the need for a broader range of studies researching contextual effects . Few recent studies critically examined the role of education in shaping immigration attitudes in different contextual settings over time. Borgonovi and Pokropek , who establish the importance of contextual factors to the strength of this relationship, and Eick , who finds welfare chauvinism even in higher educated socioeconomic strata, are among the notable exceptions. However, they do not consider cultural and economic attitudes separately, possibly reflecting the two corresponding types of perceived threats. Moreover, it appears that scholarly attention has primarily focused on analysing attitudes toward immigration in Western European countries, while research on non-Western European countries is scarce and finds little evidence for the relationship in the non-Western area . Section title: Introduction Educational score: 1.152514100074768 Domain: other Document type: Study Language: en Our study aims to better understand if the relationship between higher education and more inclusive attitudes toward immigration still holds, given the broader context of recent socioeconomic changes and idiosyncratic differences among European countries. Our central argument is that education’s liberalising role is present but may vary under different contextual circumstances. More specifically, we expect variation in different aspects of attitudes toward immigration, namely, some contextual factors may come into play when defining the role of education in shaping cultural attitudes, while others may trigger changes in economic attitudes. We, thus, bring together individual and contextual factors to explain differences in attitudes toward immigration across countries and over time, with particular attention to regional differences. Section title: Introduction Educational score: 1.0030865669250488 Domain: other Document type: Study Language: en Our contribution begins by analysing two aspects of immigration attitudes separately rather than combining them into a single index. Culturally, natives may view immigration as enriching or undermining their society, while economically, they may view immigration as improving or worsening the country’s economy. Interestingly, no correlation is warranted between the two aspects. Natives may welcome immigration, because it brings economic benefits but may oppose it, because they reject cultural diversity and vice versa. Thus, we distinguish these two aspects and identify possible attitudinal differences between subpopulations with different educational backgrounds. In addition, we examine the role of education in shaping cultural and economic aspects of attitudes toward immigration and its interaction with contextual variables. To this end, we consider country-specific period effects, such as changes in the inflows of foreign-born populations and unemployment rates. Using data from the European Social Survey, we study 15 European countries—12 non-Eastern European and 3 Eastern European—between 2002 and 2018. Section title: Introduction Educational score: 0.987762987613678 Domain: other Document type: Other Language: en Our findings lend support to the liberalising and empowering role of education, with higher-educated individuals being more open to immigration and less threatened by it in both aspects than their less-educated peers. We find, however, that context matters and that some socioeconomic changes tend to mitigate this effect. By discussing the role of contextual and regional factors in this relationship, we aim to promote a broader and deeper understanding of the role of higher education in defining cultural and economic attitudes toward immigration. Section title: Theoretical background Educational score: 0.9228609800338745 Domain: other Document type: Other Language: en Scholarly interest in the question of what determines individual perceptions of immigration prompted theories at individual and contextual levels. The former focus on demographics, such as level of education , age and cohort , as well as gender . In addition, they identify political affiliation , place of residence , whether an individual was born in the country they live in , and individual satisfaction with the economy . Moreover, scholarship emphasises the impact of contextual factors such as changes in the economic situation and the cultural composition of societies , although the literature on contextual factors is somewhat limited . Section title: Theoretical background Educational score: 0.8589396476745605 Domain: other Document type: Other Language: en Among the individual-level variables, scholarship considers education to be one of the most stable predictors of attitudes toward immigration—higher-educated individuals tend to be more inclusive toward foreign groups and welcome immigration . More than only a proxy for socioeconomic status, it is assumed to have a liberalising effect on immigration attitudes . Furthermore, it is assumed that the mechanism by which educational attainment influences attitudes toward migration is a mixture of enhanced cognitive ability associated with better powers of abstraction and broader intellectual horizons, liberal societal norms and values endorsed by higher educational institutions, and better socioeconomic status, which makes immigration appear less threatening in terms of competition . Some recent studies, however, report welfare chauvinistic attitudes toward immigration, even among highly educated Europeans . Section title: Theoretical background Educational score: 0.9944946765899658 Domain: other Document type: Other Language: en Our central argument is that variance in this well-established relationship can be attributed to contextual factors such as socioeconomic changes or regional differences. For example, if immigration attitudes decline during economic downturns or rapid changes in population composition , or if there are regional discrepancies between Eastern European and non-Eastern European countries , it is plausible to expect these contextual factors to impact education’s liberalising role in defining attitudes toward immigration. Section title: Theoretical background Educational score: 0.9680090546607971 Domain: other Document type: Other Language: en Many approaches have in common that the perception of a threat posed by immigration to natives individually or collectively affects immigration attitudes . Group threat theory—the predominant theory explaining attitudes toward immigration—assumes that individuals belonging to a particular group (in-group) view it more favourably than other groups (out-groups) . This inevitably implies hostility toward out-groups, as they challenge the homogeneity of the in-group. More specifically, in-group members may become hostile toward out-groups when they feel that their national or economic interests are threatened . Section title: Theoretical background Educational score: 1.0044093132019043 Domain: other Document type: Other Language: en A perceived cultural threat is based on the fear that the identity of the out-group could jeopardise the distinct national identity, worldview, values, and traditions of the in-group . Previous research found strong evidence for the role of cultural threat in defining immigration attitudes . Moreover, it was reported that higher-educated individuals are more likely to favour cultural diversity , as higher education is often associated with support for liberal values . Section title: Theoretical background Educational score: 0.8776954412460327 Domain: other Document type: Study Language: en A perceived economic threat can manifest in egotropic and sociotropic guises. Egotropic concerns are often related to the labour–market competition hypothesis, whereby native lower socioeconomic strata may fear competition with immigrants for available lower-status jobs, leading to unfavourable attitudes toward immigration . Times of economic hardships appear to exacerbate this correlation . Conversely, studies found that a strong position in the labour market and a higher occupational classification, which is often tied to higher education, are directly linked to a positive attitude toward immigration . However, the premise of the labour–market competition—that natives would oppose immigrants with a similar socioeconomic level and skill set as themselves—was refuted by other studies . They found that, regardless of their socioeconomic status, natives favoured better-educated, highly skilled immigrants . Section title: Theoretical background Educational score: 0.9018010497093201 Domain: other Document type: Other Language: en From a sociotropic perspective, negative views of the national economy are associated with less favourable immigration attitudes . Natives may fear that immigrants put the national welfare system under strain, increasing competition for the distribution of welfare resources . Furthermore, the cost of accommodating immigrants may be reflected in the taxes paid by higher earners, resulting in anti-immigration sentiments in the higher socioeconomic strata . The literature, therefore, agrees that opposition to immigration is primarily driven by national sociotropic rather than egotropic concerns . Section title: Theoretical background Educational score: 1.005797028541565 Domain: other Document type: Other Language: en The recent socioeconomic changes in Europe make the aggravation of the perceived cultural and economic threats plausible. The economic crises of the first two decades of the third millennium put the remnants of national welfare systems in Europe under pressure; economic security and solidarity gave way to austerity. According to the hypothesis that economic hardship breeds extremism, we expect it to have influenced the perception of the economic threat out-groups pose. The same could be true, given the ethnocultural diversity fostered by the recent influx of immigrants and refugees into European countries. These changes, however, did not affect all European countries equally. The Eurozone crisis, for example, hit the so-called “PIIGS” group of countries comprising Portugal, Ireland, Italy, Greece, and Spain the hardest. These countries not only suffered from a deep economic recession but also had to implement harsh austerity measures imposed by the EU . The impact of the 2015 refugee crisis was also asymmetrical among European countries. Germany, Norway, Sweden, and Switzerland were popular destination countries that received the most asylum seekers. In contrast, countries such as Greece, Italy, Hungary, and Slovenia were transit countries due to their location on the European entry routes, with Hungary recording the highest number of asylum seekers . Section title: Theoretical background Educational score: 1.2210842370986938 Domain: other Document type: Study Language: en These socioeconomic changes require a reassessment of the established predictors of attitudes toward immigration. Will the liberalising and empowering role of higher education in shaping economic and cultural attitudes toward immigration change significantly in the face of these changes? We conceptualise the liberalising role of education in shaping cultural and economic attitudes as the difference in attitudes between higher-educated and lower-educated people. Our study tests the hypothesis that higher education—a mix of enhanced cognitive skills associated with better abstracting ability, broader intellectual horizons, greater openness to cultural diversity, and better socioeconomic status—is empowering and thus makes immigration less threatening in terms of economic and cultural competition, considering regional differences and changing rates of unemployment and influx of immigrants over the years: H1: The liberalising role of education remains positive and significant in both aspects, even in times of a high influx of immigrants and economic hardship. Section title: Theoretical background Educational score: 1.0384372472763062 Domain: other Document type: Other Language: en Following our theoretical premise, we expect some contextual factors to be more prominent in defining the role of education in shaping cultural attitudes and others in shaping economic attitudes. This further supports our decision to examine these two dimensions of immigration attitudes separately rather than combining them into a single index . For example, fluctuations in migration rates, such as during the European refugee crisis, may catalyse negative cultural attitudes toward immigration, thereby affecting education’s liberalising role. Group conflict theory, particularly integrated threat theory, suggests that a high influx of migrants may increase perceptions of competition over intangible cultural resources, such as in-group values, tradition, identity, and language . This perceived cultural threat will likely foster unfavourable attitudes toward immigration . As higher education is generally associated with more liberal values , higher educated are more supportive of cultural diversity and less prone to prejudice than lower educated. We, therefore, expect the gap in cultural attitudes toward immigration between higher and lower educated to widen as the influx of migrants increases and cultural diversity becomes more apparent. Section title: Theoretical background Educational score: 1.0872023105621338 Domain: other Document type: Other Language: en A high influx of immigrants can also heighten perceptions of competition over tangible resources, such as access to social benefits and tax burdens, thus intensifying perceptions of an economic threat. Previous studies suggest that less educated individuals from lower socioeconomic backgrounds are particularly susceptible to threat perceptions . Other studies indicate that higher socioeconomic strata may also develop less favourable immigration attitudes, because they fear the costs of accommodating immigrants through higher taxes . Therefore, we do not expect the difference in economic attitudes between higher and lower educated to increase significantly in times of increased migration inflows as both lower and higher educated may perceive it as an economic threat: H2: A higher influx of immigrants will increase education’s liberalising role for cultural attitudes but not for economic ones. Section title: Theoretical background Educational score: 0.9693192839622498 Domain: other Document type: Other Language: en Rising unemployment rates, such as during the Great Recession and the European sovereign debt crisis, are associated with increasingly hostile attitudes toward immigration and can be expected to affect the liberalising role of education. If immigrants are assumed to be less educated and compete for similar types of jobs as the less educated natives belonging to the lower socioeconomic strata, we may expect the latter to develop negative attitudes toward immigration due to perceived competition for lower-status jobs . In contrast, better-educated individuals in higher socioeconomic strata, often associated with more favourable immigration attitudes , are typically employed in professions less affected by immigration, which reduces the likelihood of direct job competition. Therefore, we expect that economic hardship, proxied by fluctuations in unemployment rates, will widen the gap in economic attitudes toward immigration between the lower and higher educated. Section title: Theoretical background Educational score: 1.0438365936279297 Domain: other Document type: Study Language: en Economic factors such as rising unemployment appear to influence not only economic but also cultural attitudes toward immigration . Studies documented a so-called “spillover effect”, whereby economic hardship amplifies cultural concerns about immigration, accentuating in-group versus out-group distinctions, particularly among economically vulnerable, lower-educated individuals . Conversely, higher-educated individuals, who are typically more open to cultural diversity, are less likely to perceive cultural threats in times of economic downturn due to a relatively stable socioeconomic status and more inclusive value systems . Therefore, we expect the “spillover effect” of economic hardship on cultural attitudes toward immigration mostly among lower-educated individuals, reinforcing education’s liberalising role: H3: Economic hardship will increase education’s liberalising role for both economic and cultural attitudes. Section title: Theoretical background Educational score: 1.0330926179885864 Domain: other Document type: Study Language: en In addition, this study examines regional differences between Eastern European and non-Eastern European countries to contribute to the scarce literature studying immigration attitudes in non-Anglo contexts . Section title: Data Educational score: 1.1730093955993652 Domain: other Document type: Study Language: en In this study, we analyse data from the European Social Survey (ESS)—a cross-national survey that began in 2002 and is conducted every 2 years with face-to-face interviews. The data set offers two separate questions on cultural and economic aspects of attitudes toward immigration, which have the same wording in all nine rounds and are relevant to this study. We use data from 15 countries (Belgium, Finland, France, Germany, Hungary, Ireland, the Netherlands, Norway, Poland, Portugal, Slovenia, Spain, Sweden, Switzerland, and the United Kingdom) that participated in all nine waves. Furthermore, we use data from FAOSTAT for population size, OECD and SiStat for migrant inflows, and data from the World Bank for unemployment rates . Section title: Data Educational score: 1.047336459159851 Domain: other Document type: Other Language: en Our two outcome variables—cultural and economic attitudes toward immigration—were addressed by the following questions, with responses rated on an 11-point Likert scale: 1. A country’s cultural life is undermined or enriched by immigrants. Would you say that [respondent’s country]’s cultural life is generally undermined or enriched by people coming to live here from other countries? (0 = cultural life undermined; 10 = cultural life enriched). 2. Immigration is bad or good for a country’s economy. Would you say it is generally bad or good for [respondent’s country]’s economy that people come to live here from other countries? (0 = bad for the economy; 10 = good for the economy). Section title: Data Educational score: 1.715682864189148 Domain: other Document type: Study Language: en Participants’ individual level of education was classified into five ISCED categories using the International Standard Classification of Education (ISCED-97): (1) less than lower secondary education (ISCED I); (2) lower secondary education (ISCED II); (3) upper secondary education (ISCED III); (4) advanced vocational education (ISCED IV); and (5) at least lower tertiary education, B.A. level (ISCED V). Section title: Data Educational score: 1.1273545026779175 Domain: other Document type: Study Language: en Among the individual control variables, we include satisfaction with the economy (0 = extremely dissatisfied; 10 = extremely satisfied), following the literature that shows that natives have unfavourable attitudes toward immigration in times of economic hardship . In addition, we consider gender and whether a respondent is from the country they live in, as these were shown to affect attitudes toward immigration . Moreover, we consider the contact theory, according to which a higher proportion of immigrants are found in big cities than in rural areas , by including a variable for residence (0 = big cities; 1 = rural areas). We also account for left–right political affiliation (0 = left; 10 = right) as exposure to right-wing populist rhetoric was found to promote anti-immigrant attitudes . The age of the participants, ranging from 14 to 123 years, was categorised into 10-year groups, as some studies found a non-linear association between age and attitudes toward immigration . Section title: Data Educational score: 1.2459906339645386 Domain: other Document type: Study Language: en We consider the following contextual factors in our analysis: (1) the migrant inflow rate, i.e., the foreign population that immigrated to a country in the year prior to the respective survey year, divided by the country’s total population and presented in percentage points (summary statistics are provided in Table A1 in the appendix); (2) the unemployment rate in the survey year, which indicates the share of the labour force that was unemployed but was actively seeking employment. These contextual factors represent a changing socioeconomic environment. In addition, they may account for a possible cultural and economic threat from newcomers, as natives can develop hostile attitudes toward immigration if their cultural and economic interests are threatened . Section title: Methods Educational score: 1.4935489892959595 Domain: other Document type: Study Language: en We investigate the role of education and contextual factors (i.e., migrant inflow rate and unemployment rate) in shaping the two aspects of respondents’ attitudes toward immigration (cultural and economic) by examining the sample from 15 European countries that participated in nine ESS waves over 16 years. We begin our analysis with a descriptive overview of net attitudes toward immigration in cultural and economic aspects in the selected countries. For the descriptive statistics, we convert the 11-point Likert scale of both variables on attitudes toward immigration into a binary positive/negative attitude, using five as the cutoff point: All values greater than five were coded as positive, while values equal to or less than five were coded as negative attitudes toward immigration. To estimate the net percentage, we subtracted the percentage of respondents who reported negative attitudes toward immigration from those who had positive attitudes in each aspect for each country. We report average cultural and economic attitudes toward immigration for non-Eastern European and Eastern European countries. In addition, we present net attitudes for each survey year over 16 years for non-Eastern and Eastern European countries as well as the entire sample. Section title: Methods Educational score: 3.1383612155914307 Domain: other Document type: Study Language: en There is evidence in the literature of temporal trends in attitudes toward immigration, which could be period or cohort effects. For example, McLaren and Paterson identified cohort effects in European data, Wilkes and Corrigall-Brown found a strong period effect and only a small cohort effect in Canadian data, while Beller found cohort and period effects when analysing German data. However, the linearity between age, period, and cohorts requires special consideration in the modelling strategy. Therefore, following the statistics and migration literature, we address the potential confounding influence of age and periods by applying hierarchical age-period-cohort regression analysis (HAPC) . More specifically, we apply a hierarchical cross-classified random effects model . This model allows us to account for the hierarchical structure of the unbalanced repeated cross-sectional data, with individuals being cross-classified and nested in both country-period and country-cohort while clustered in 15 European countries. Thus, we estimate the variability across periods and cohorts while testing the role of individual education and contextual (country-period) factors. In our approach, we enter age as a level one variable, country-period and country-cohort as cross-classified level two units, and country as a level three variable. Moreover, we add individual-level variables to the participants’ characteristics, such as education, gender, place of residence, native population group membership, left–right party affiliation, satisfaction with the economy and country-period variables, and contextual variables, such as migrant inflow rate and unemployment rate. Section title: Methods Educational score: 2.5343520641326904 Domain: other Document type: Study Language: en The two aspects of attitudes toward immigration are analysed separately with individual-level (Level 1), country-cohort (Level 2), country-year (Level 2), and country-level (Level 3) effects. We ran the following models for each outcome variable: First, we estimate a null hierarchical three-level cross-classified model (Model 0). Model 1 examines the effect of education on cultural and economic attitudes toward immigration while controlling for individual-level factors. Then, we add contextual country-period factors on socioeconomic changes with model 2a, including the migrant inflow rate and model 2b, including the unemployment rate. In model 3a, the interaction between individual education and country-period variable migrant inflow rate is added, whereas model 3b adds the interaction between individual education and the unemployment rate. Model 3 can be written as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${y}_{ijkl}={\upbeta }_{0}+{\upbeta }_{1}\,{X}_{ijkl}+{\upbeta }_{2}\,Edu{c}_{ijkl}+{\upbeta }_{3}{T}_{kl}+{\upbeta }_{4}Edu{c}_{ijkl}\times {T}_{kl}+{u}_{0jl}+{\upnu }_{0kl}+{\upomega }_{0l}+{e}_{0ijkl}$$\end{document} y ijkl = β 0 + β 1 X ijkl + β 2 E d u c ijkl + β 3 T kl + β 4 E d u c ijkl × T kl + u 0 j l + ν 0 k l + ω 0 l + e 0 i j k l where \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$y_{ijkl}$$\end{document} y ijkl is the attitude toward migration score for individual i within country-cohort j, country-period k, and country l. Furthermore, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${X}_{ijkl}$$\end{document} X ijkl is a vector of the individual-level factors we control for, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$Edu{c}_{ijkl}$$\end{document} E d u c ijkl is the individual education, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{kl}$$\end{document} T kl is the country-period characteristics (either the migrant inflow rate or the unemployment rate), and the residual random effects of individual ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${e}_{0ijkl}$$\end{document} e 0 i j k l ), country-cohort ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${u}_{0jl}$$\end{document} u 0 j l ), country-period ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\upnu }_{0kl}$$\end{document} ν 0 k l ), and country ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\upomega }_{0l}$$\end{document} ω 0 l ), where the random effects are all assumed to be normally distributed with mean 0. Section title: Methods Educational score: 1.6724905967712402 Domain: biomedical Document type: Study Language: en Moreover, we consider regional differences in our country pool, namely, the division into Eastern and non-Eastern Europe. Therefore, we ran all our models separately on the subsample of Eastern European countries (Hungary, Poland, and Slovenia) and Non-Eastern European countries. In our analysis, we corrected for non-response and population size by including survey weights. Section title: Descriptive results Educational score: 1.1995340585708618 Domain: other Document type: Study Language: en First, we examine how attitudes toward immigration differ culturally and economically across the European countries in our sample. Table 1 reports individual net attitudes toward immigration in cultural and economic aspects in the 15 selected countries, with the top and bottom 15% of values highlighted in bold to facilitate comparison. On average, respondents tended to have positive attitudes toward immigration in cultural terms (14.6%) but negative attitudes in economic terms (− 12.8%) (Table 1 ). Table 1 Net share of respondents reporting cultural and economic attitudes toward immigration by country Country Net cultural attitude Net economic attitude Non-Eastern Europe Belgium 13.9 − 29.2 Finland 59.3 − 4.0 France − 6.9 − 28.6 Germany 14.3 − 6.5 Ireland 10.5 − 0.9 Netherlands 33.1 − 11.7 Norway 10.9 − 0.7 Portugal 2.1 − 14.4 Spain 22.5 − 1.6 Sweden 51.5 3.6 Switzerland 21.6 18.7 United Kingdom − 5.5 − 19.5 Average 18.9 − 7.9 Eastern Europe Hungary − 17.4 − 50.5 Poland 27.0 − 6.5 Slovenia − 18.6 − 39.4 Average − 3.0 − 32.2 Total Sample Average 14.6 − 12.8 Values on the 11-point Likert scale above five were summarised as positive attitudes, while values less than or equal to five were coded as negative attitudes; the net percentage was calculated by subtracting the percentage of respondents indicating a negative attitude from those indicating a positive attitude in each aspect; the top and bottom 15% values are in bold; survey weights were considered Source: European Social Survey 2002–2018, 15 European countries Section title: Descriptive results Educational score: 1.1462253332138062 Domain: other Document type: Study Language: en The non-Eastern European sub-sample supports this trend, demonstrating even greater tolerance toward immigration in the cultural aspect (18.9%) and less intolerance in the economic aspect (− 7.9%) than the general sample. This tendency was consistent with most of the countries in the subsample, except for Sweden and Switzerland—the only two countries with positive attitudes toward immigration also in the economic aspect (3.6% and 18.7%, respectively)—and France and the UK, which showed negative attitudes in both aspects to varying degrees. The most positive attitudes were found in Finland and Sweden, which appear to be the most culturally favourable toward immigration, with 59.3% and 51.5% of respondents, respectively. Section title: Descriptive results Educational score: 1.0766037702560425 Domain: other Document type: Study Language: en The Eastern European sub-sample, however, indicates that, on average, respondents had predominantly negative attitudes toward immigration in both aspects. Specifically, intolerance toward immigration was lower in the cultural aspect (− 3%) than in the economic aspect (− 32.2%). Hungary and Slovenia showed the most negative net attitudes toward immigration in both aspects, with Slovenia (− 18.6%) in the cultural aspect and Hungary (− 50.5%) in the economic aspect, achieving the lowest score not only in the Eastern European sub-sample but also among all 15 countries. In contrast, the attitudes reported by Poland were more in line with those of the non-Eastern European sub-sample, showing positive attitudes in the cultural aspect (27%) and slightly negative attitudes in the economic aspect (− 6.5%). Section title: Descriptive results Educational score: 1.0316792726516724 Domain: other Document type: Study Language: en The division of the sample into Eastern European and non-Eastern European countries revealed that, on average, the three Eastern European countries had a negative net attitude in cultural and especially economic terms, while the average net attitudes of the non-Eastern European countries were above the average of the total sample. Despite the idiosyncratic differences in attitudes toward immigration, the descriptive results at the individual country level confirm the general trend that Europeans are less supportive of immigration from an economic perspective than from a cultural perspective. According to these findings, developing an economic threat perception is more likely than a cultural one. Section title: Descriptive results Educational score: 1.1290624141693115 Domain: other Document type: Study Language: en Using average scores over such a long period could hide important temporal effects. Therefore, we examine how cultural and economic attitudes toward immigration vary over time in our sample. Figures 1 and 2 show the evolution of net cultural and economic attitudes toward immigration in non-Eastern and Eastern European countries over 16 years and the average net attitudes per year, respectively. The sparklines on the right side of the figures mark the positive net attitudes of the countries in blue and the negative ones in red. The mini graphs at the bottom of the sparklines show the evolution of cultural or economic attitudes in each sub-sample and the total sample of countries over time. Fig. 1 Net share of respondents reporting cultural attitudes toward immigration by country and year. Source: European Social Survey, 2002–2018. The net percentage was calculated by subtracting the percentage of respondents who indicated a negative cultural attitude from those with a positive cultural attitude; sampling weights were considered Fig. 2 Net share of respondents reporting economic attitudes toward immigration by country and year. Source: European Social Survey, 2002–2018. The net percentage was calculated by subtracting the percentage of respondents who indicated a negative economic attitude from those with a positive economic attitude; sampling weights were considered Section title: Descriptive results Educational score: 1.024001955986023 Domain: other Document type: Study Language: en Following the group threat theory literature, we expected the Eurozone crisis and the European refugee crisis to affect attitudes toward immigration negatively. The average values for the entire sample indicate that the net attitude toward immigration in cultural and economic aspects dropped in 2010, but this was reversed in 2012. Thus, the Eurozone crisis may have been associated with a short-term decline in attitudes toward immigration. In contrast, average net attitudes toward immigration in both aspects increased steadily between 2014 and 2018, indicating a more welcoming stance across the entire sample. Overall, our descriptive results indicate that the refugee crisis was not linked to less favourable net attitudes toward immigration—quite the opposite. This corroborates previous findings and refutes our expectation that the refugee crisis might have reduced positive attitudes toward immigration. Section title: Descriptive results Educational score: 0.9620586037635803 Domain: other Document type: Other Language: en Interestingly, the least positive total average net attitude toward immigration in both aspects was in 2004. While the number of refugees worldwide declined sharply in 2003 , European countries faced the most extensive enlargement of the EU when ten new Member States (seven of them from Eastern Europe, including Hungary, Poland, and Slovenia) joined the EU in May 2004. This considerable wave of EU enlargement may have raised doubts among existing Member States about how it might affect their cultural and economic situation. Separating the Eastern European countries from the rest of our sample helps to clarify this point, as the negative slump in 2004 occurred only among the non-Eastern European countries . It also urges a closer look at the differences between our sub-samples. Section title: Descriptive results Educational score: 0.9978400468826294 Domain: other Document type: Study Language: en The mini graphs for the sub-samples on the right side of Figs. 1 and 2 illustrate that, on average, attitudes toward immigration have become more positive in non-Eastern European countries in recent years, with 2018 recording the most positive attitudes toward immigration in both aspects. They also indicate a momentary drop in both attitudes in 2010 that can be associated with the Eurozone crisis. These findings are consistent with the entire sample, revealing that the Eurozone crisis was briefly associated with a decline in both immigration attitudes, while the refugee crisis had no negative association, with cultural attitudes becoming more positive since 2016. Section title: Descriptive results Educational score: 0.9304395318031311 Domain: other Document type: Study Language: en There are stark differences, however, in the Eastern European sub-sample. Economically, the countries appear to have become less intolerant of immigration in 2018, but their attitudes are still decidedly negative . Culturally, there has been a substantial decline in average net attitudes among the Eastern European countries, starting in 2014 and continuing until 2018 . The sparklines indicate that, among the three countries, Hungary and Slovenia set the negative tone for the sub-sample in both aspects (red). In contrast, Poland shows a positive attitude toward immigration in cultural terms (blue) and a mixed trend in economic terms. This could be related to the fact that Hungary and Slovenia served as entry portals for refugees coming to Europe during the refugee crisis, while Poland was not directly affected by the influx of migrants. However, the refugee crisis can be linked to more negative economic attitudes in all three Eastern European countries. The Eurozone crisis, on the other hand, is not associated with a decline in either aspect of attitudes toward immigration, as the average scores in the sub-sample show no negative change in the years in question . These results contradict the entire sample and the non-Eastern European sub-sample findings. Section title: Descriptive results Educational score: 1.3246995210647583 Domain: other Document type: Study Language: en Overall, our descriptive results suggest that economic hardships rather than cultural changes that might be related to an increasing number of asylum seekers are more likely to generate negative attitudes toward immigration. This is an interesting finding, as during the 2015 refugee crisis, many asylum seekers arriving in Europe were fleeing persecution in Syria, Afghanistan, and Iraq—countries of predominantly Muslim origin . Nevertheless, the ongoing debate about the perceived rejection of liberal norms and values by Muslim immigrants , which could have exacerbated the perception of a cultural threat, was not associated with a more negative attitude toward immigration in the whole sample. However, complementing previous studies , we found large discrepancies between non-Eastern European and Eastern European countries in both aspects of attitudes toward immigration. There were differences in reported net attitudes as such and in the potential impact of the Eurozone and refugee crises. Section title: Results of the analysis Educational score: 3.3296658992767334 Domain: other Document type: Study Language: en Our results from the hierarchical three-level cross-classified null model show that the smallest proportion of variance in cultural attitudes is explained by the period effect (country-period: 1.2%), followed by the cohort effect (country-cohort: 2.6%) (Model 0; Table 2 ), confirming the not too prominent role of the period already emphasised in our descriptive results. However, in the Eastern European countries, the period effect explains 4.2%, while in the non-Eastern European countries, it explains only 0.7% of the variance (Model 0; Tables 4 and 5 ), meaning that period effects manifest stronger in Eastern European countries than in their non-Eastern counterparts. This is different for economic attitudes. While the variance between country-cohort explains 1.1% and country-period 2.15% of the variance in economic attitudes in the pooled sample, the cohort effect only contributes to a small extent to explaining the variance in economic attitudes among the non-Eastern European countries (country-cohort: 0.9% and country-period: 2.2%) (Model 0; Tables 3 and 7 ). The contribution of the cohort and period effects is of a similar magnitude among the Eastern European countries (country-cohort: 2.5% and country-period: 2.0%) (Model 0; Tables 6). The random period effect illustrated in Fig. 3 only shows statistically significant negative changes in cultural attitudes after 2012 in Hungary and Poland and, to a smaller extent, in Slovenia. However, there have been significant changes over time in economic attitudes in most countries . For example, in Germany, Ireland, Portugal, and the United Kingdom, economic attitudes became significantly more positive after 2010 and 2012. Table 2 Hierarchical, three-level, crossed-classified random effects models of cultural attitudes toward immigration in 15 European countries Model 0 Model 1 Model 2a Model 3a Model 2b Model 3b Intercept 5.767 (0.162) *** 5.962 (0.146) *** 6.148 (0.158) *** 5.960 (0.159) *** 5.61 (0.153) *** 5.652 (0.155) *** Individual level Education (ref: ISCED I) ISCED II 0.347 (0.019) *** 0.347 (0.019) *** 0.524 (0.035) *** 0.347 (0.019) *** 0.333 (0.038) *** ISCED III 0.654 (0.018) *** 0.654 (0.018) *** 0.846 (0.032) *** 0.654 (0.018) *** 0.538 (0.038) *** ISCED IV 1.088 (0.022) *** 1.088 (0.022) *** 1.427 (0.040) *** 1.087 (0.022) *** 1.037 (0.045) *** ISCED V 1.656 (0.019) *** 1.656 (0.019) *** 1.862 (0.034) *** 1.656 (0.019) *** 1.665 (0.037) *** Country-period level Migrant inflow rate − 0.244 (0.087) ** 0.019 (0.093) Unemployment rate 0.045 (0.009) *** 0.040 (0.010) *** ISCED II x migrant inflows − 0.261 (0.042) *** ISCED III x migrant inflows − 0.289 (0.040) *** ISCED IV x migrant inflows − 0.453 (0.045) *** ISCED V x migrant inflows − 0.306 (0.041) *** ISCED II x unemployment 0.001 (0.004) ISCED III x unemployment 0.014 (0.004) *** ISCED IV x unemployment 0.006 (0.005) ISCED V x unemployment − 0.002 (0.004) Random effects: var Country (level 3) 0.337 0.282 0.272 0.270 0.238 0.237 Country-period (level2) 0.083 0.101 0.095 0.095 0.085 0.085 Country-cohort (level 2) 0.178 0.024 0.024 0.023 0.025 0.025 Residual 6.323 5.529 5.529 5.527 5.529 5.529 N 245,291 219,299 219,299 219,299 219,299 219,299 Higher scores indicate a more positive attitude; *p<0.05, **p<0.01, ***p<0.001; sampling weights are considered; model 0 represents the null model, model 1 presents the coefficients (S.E.) of education with ISCED I as reference category and individual characteristics as control variables; model 2 adds contextual variables migrant inflow rate (model 2a) and unemployment rate (model 2b); model 3 adds the interaction of education and contextual variables (migrant inflow rate in model 3a and unemployment rate in model 3b); the complete table with a list of all individual-level control variables can be found in Table A2 in the appendix Table 3 Hierarchical, three-level, crossed-classified random effects models of economic attitudes toward immigration in 15 European countries Model 0 Model 1 Model 2a Model 3a Model 2b Model 3b Intercept 5.038 (0.146) *** 4.529 (0.122) *** 4.446 (0.133) *** 4.333 (0.135) *** 4.592 (0.141) *** 4.682 (0.143) *** Individual level Education (ref: ISCED I) ISCED II 0.388 (0.019) *** 0.388 (0.019) *** 0.507 (0.034) *** 0.388 (0.019) *** 0.317 (0.037) *** ISCED III 0.636 (0.018) *** 0.636 (0.018) *** 0.736 (0.031) *** 0.636 (0.018) *** 0.498 (0.036) *** ISCED IV 1.062 (0.021) *** 1.061 (0.021) *** 1.240 (0.039) *** 1.062 (0.021) *** 1.018 (0.044) *** ISCED V 1.619 (0.018) *** 1.619 (0.018) *** 1.763 (0.033) *** 1.619 (0.018) *** 1.484 (0.036) *** Country-period level Migrant inflow rate 0.109 (0.075) 0.267 (0.081) ** Unemployment rate − 0.008 (0.008) − 0.018 (0.009) * ISCED II x migrant inflows − 0.174 (0.040) *** ISCED III x migrant inflows − 0.152 (0.038) *** ISCED IV x migrant inflows − 0.243 (0.043) *** ISCED V x migrant inflows − 0.210 (0.039) *** ISCED II x unemployment 0.008 (0.003) * ISCED III x unemployment 0.016 (0.004) *** ISCED IV x unemployment 0.004 (0.004) ISCED V x unemployment 0.015 (0.003) *** Random effects: var Country (level 3) 0.287 0.192 0.186 0.185 0.203 0.203 Country-period (level2) 0.139 0.070 0.069 0.069 0.069 0.069 Country-cohort (level 2) 0.073 0.018 0.018 0.018 0.018 0.018 Residual 5.974 5.108 5.108 5.107 5.108 5.108 N 244,946 218,672 218,672 218,672 218,672 218,672 Higher scores indicate a more positive attitude; *p<0.05, **p<0.01, ***p<0.001; sampling weights are considered; model 0 represents the null model, model 1 presents the coefficients (S.E.) of education with ISCED I as reference category and individual characteristics as control variables; model 2 adds contextual variables migrant inflow rate (model 2a) and unemployment rate (model 2b); model 3 adds the interaction of education and contextual variables (migrant inflow rate in model 3a and unemployment rate in model 3b); the complete table with a list of all individual-level control variables can be found in Table A3 in the appendix Fig. 3 Period random effect estimates on cultural attitude from the hierarchical, three-level, cross-classified null model Fig. 4 Period random effect estimates on economic attitude from the hierarchical, three-level, cross-classified null model Section title: Results of the analysis Educational score: 1.5494862794876099 Domain: other Document type: Study Language: en When individual characteristics are added (Model 1; Tables 2 and 3 ), our results suggest that respondents with a higher level of education are significantly more sympathetic toward immigration in both aspects than those with a lower level of education. Thus, our results confirm education’s liberalising role in shaping cultural and economic immigration attitudes while controlling for individual characteristics such as demographics, political affiliation, and satisfaction with the economy. Interestingly, the magnitude of education’s liberalising role remains unchanged when migrant inflow rates are added (Model 2a; Tables 2 and 3 ). However, higher migrant inflow rates are statistically negatively significant for cultural attitudes (Model 2a, Table 2 ), whereas they have no significant effect on economic attitudes (Model 2a, Table 3 ). In addition, higher migrant inflow rates attenuate education’s liberalising role in shaping cultural attitudes, as indicated by a significant negative interaction between education and migrant inflow rates (Model 3a, Table 2 ). The influx of migrants has no significant influence on economic attitudes. However, the interaction between education and migrant inflow rates is significant, with higher migrant inflow rates slightly reducing education’s liberalising role in economic attitudes (Model 3a, Table 3 ). In addition, the attenuation of education’s liberalising role ensuing from higher migrant inflow rates is greater for the lower educated than for the higher educated. Section title: Results of the analysis Educational score: 0.985273540019989 Domain: other Document type: Study Language: en Economic hardship, proxied by the unemployment rate, is significantly positive for cultural attitudes (Model 2b, Table 2 ) but has no significant interaction with education (Model 3b, Table 2 ). Interestingly, while the unemployment rate is insignificant for economic attitudes (Model 2b; Table 3 ), it supports education’s liberalising role in shaping economic attitudes (Model 3b, Table 3 ). Section title: Results of the analysis Educational score: 2.45249080657959 Domain: other Document type: Study Language: en A look at the differences in the role of education and contextual factors for non-Eastern and Eastern European countries—countries with different migration histories—reveals that for cultural attitudes, migrant inflow rates are negatively significant in non-Eastern European countries while insignificant in Eastern European countries (Model 2a, Tables 4 and 5 ). In non-Eastern European countries, higher migrant inflow rates also reduce education’s liberalising role (Model 2b, Table 5 ). This is different for the economic hardship hypothesis. Higher unemployment rates are significantly positive for cultural attitudes in both non-Eastern and Eastern European countries (Model 3a, Tables 4 and 5 ), while the interaction is insignificant (Model 3b). Table 4 Hierarchical, three-level, crossed-classified random effects models of cultural attitudes toward immigration in 3 Eastern European countries Model 0 Model 1 Model 2a Model 3a Model 2b Model 3b Intercept 5.267 (0.392) ** 5.476 (0.409) *** 5.777 (0.415) *** 5.965 (0.425) *** 4.835 (0.382) *** 4.716 (0.43) *** Individual level Education (ref: ISCED I) ISCED II − 0.048 (0.097) − 0.048 (0.097) − 0.24 (0.138) − 0.048 (0.097) 0.19 (0.233) ISCED III 0.399 (0.098) *** 0.4 (0.098) *** 0.251 (0.138) 0.398 (0.098) *** 0.491 (0.231) * ISCED IV 0.706 (0.11) *** 0.706 (0.11) *** 0.497 (0.154) ** 0.704 (0.11) *** 0.583 (0.256) * ISCED V 1.016 (0.101) *** 1.016 (0.101) *** 0.725 (0.143) *** 1.015 (0.101) *** 1.169 (0.237) *** Country-period level Migrant inflow rate − 0.704 (0.432) − 1.612 (0.629) * Unemployment rate 0.076 (0.025) ** 0.089 (0.033) ** ISCED II x migrant inflows 0.948 (0.487) ISCED III x migrant inflows 0.719 (0.473) ISCED IV x migrant inflows 1.022 (0.527) ISCED V x migrant inflows 1.443 (0.491) ** ISCED II x unemployment − 0.024 (0.022) ISCED III x unemployment − 0.009 (0.022) ISCED IV x unemployment 0.012 (0.024) ISCED V x unemployment − 0.015 (0.023) Random effects: var Country (level 3) 0.405 0.413 0.33 0.327 0.225 0.222 Country-period (level2) 0.213 0.257 0.243 0.245 0.198 0.197 Country-cohort (level 2) 0.129 0.044 0.045 0.045 0.045 0.044 Residual 4.754 4.535 4.535 4.533 4.535 4.534 N 39,548 32,285 32,285 32,285 32,285 32,285 Higher scores indicate a more positive attitude; *p<0.05, **p<0.01, ***p<0.001; sampling weights are considered; model 0 represents the null model, model 1 presents the coefficients (S.E.) of education with ISCED I as reference category and individual characteristics as control variables; model 2 adds contextual variables migrant inflow rate (model 2a) and unemployment rate (model 2b); model 3 adds the interaction of education and contextual variables (migrant inflow rate in model 3a and unemployment rate in model 3b); the complete table with a list of all individual-level control variables can be found in Table A4 in the appendix Table 5 Hierarchical, three-level, crossed-classified random effects models of cultural attitudes toward immigration in 12 non-Eastern European countries Model 0 Model 1 Model 2a Model 3a Model 2b Model 3b Intercept 5.891 (0.166) *** 6.097 (0.158) *** 6.28 (0.165) *** 6.057 (0.166) *** 5.856 (0.165) *** 5.884 (0.166) *** Individual level Education (ref: ISCED I) ISCED II 0.355 (0.02) *** 0.356 (0.02) *** 0.549 (0.039) *** 0.355 (0.02) *** 0.328 (0.04) *** ISCED III 0.642 (0.019) *** 0.642 (0.019) *** 0.815 (0.034) *** 0.642 (0.019) *** 0.561 (0.04) *** ISCED IV 1.098 (0.023) *** 1.099 (0.023) *** 1.497 (0.043) *** 1.097 (0.023) *** 1.073 (0.047) *** ISCED V 1.69 (0.02) *** 1.691 (0.02) *** 2.006 (0.036) *** 1.69 (0.02) *** 1.688 (0.038) *** Country-period level Migrant inflow rate − 0.217 (0.072) ** 0.083 (0.079) Unemployment rate 0.032 (0.009) *** 0.029 (0.009) ** ISCED II x migrant inflows − 0.285 (0.045) *** ISCED III x migrant inflows − 0.27 (0.041) *** ISCED IV x migrant inflows − 0.516 (0.047) *** ISCED V x migrant inflows − 0.44 (0.043) *** ISCED II x unemployment 0.003 (0.004) ISCED III x unemployment 0.01 (0.004) * ISCED IV x unemployment 0.002 (0.005) ISCED V x unemployment 0 (0.004) Random effects: var Country (level 3) 0.276 0.269 0.253 0.25 0.237 0.236 Country-period (level2) 0.053 0.061 0.055 0.055 0.054 0.054 Country-cohort (level 2) 0.191 0.025 0.025 0.023 0.026 0.026 Residual 6.625 5.67 5.67 5.665 5.67 5.669 N 205,743 187,014 187,014 187,014 187,014 187,014 Higher scores indicate a more positive attitude; *p<0.05, **p<0.01, ***p<0.001; sampling weights are considered; model 0 represents the null model, model 1 presents the coefficients (S.E.) of education with ISCED I as reference category and individual characteristics as control variables; model 2 adds contextual variables migrant inflow rate (model 2a) and unemployment rate (model 2b); model 3 adds the interaction of education and contextual variables (migrant inflow rate in model 3a and unemployment rate in model 3b); the complete table with a list of all individual-level control variables can be found in Table A5 in the appendix Section title: Results of the analysis Educational score: 1.9981083869934082 Domain: other Document type: Study Language: en For economic attitudes, higher migrant inflow rates significantly increase the liberalising role of education in the Eastern European countries while reducing it in the non-Eastern countries (Model 3a, Tables 6 and 7 ). While economic hardships decrease favourable economic attitudes toward immigration among the lower educated, higher education appears to mitigate this effect in the non-Eastern European countries, although it does not completely override it (Model 3b, Table 7 ). This relationship, however, is insignificant in the Eastern European countries (Model 3b, Table 6 ). Table 6 Hierarchical, three-level, crossed-classified random effects models of economic attitudes toward immigration in 3 Eastern European countries Model 0 Model 1 Model 2a Model 3a Model 2b Model 3b Intercept 4.302 (0.400) ** 4.403 (0.399) *** 4.425 (0.426) *** 4.723 (0.434) *** 4.428 (0.434) *** 4.228 (0.478) *** Individual level Education (ref: ISCED I) ISCED II − 0.139 (0.098) − 0.139 (0.098) − 0.394 (0.14) ** − 0.139 (0.098) 0.08 (0.232) ISCED III 0.22 (0.098) * 0.22 (0.098) * − 0.059 (0.139) 0.22 (0.098) * 0.466 (0.23) * ISCED IV 0.49 (0.11) *** 0.49 (0.11) *** 0.133 (0.156) 0.49 (0.11) *** 0.537 (0.256) * ISCED V 0.839 (0.102) *** 0.839 (0.102) *** 0.425 (0.144) ** 0.839 (0.102) *** 0.951 (0.237) *** Country-period level Migrant inflow rate − 0.053 (0.329) − 1.535 (0.577) ** Unemployment rate − 0.003 (0.019) 0.018 (0.028) ISCED II x migrant inflows 1.236 (0.503) * ISCED III x migrant inflows 1.371 (0.489) ** ISCED IV x migrant inflows 1.758 (0.544) ** ISCED V x migrant inflows 2.054 (0.507) *** ISCED II x unemployment − 0.023 (0.022) ISCED III x unemployment − 0.025 (0.022) ISCED IV x unemployment − 0.006 (0.024) ISCED V x unemployment − 0.011 (0.022) Random effects: var Country (level 3) 0.428 0.412 0.421 0.414 0.421 0.424 Country-period (level2) 0.112 0.106 0.11 0.111 0.111 0.11 Country-cohort (level 2) 0.146 0.024 0.024 0.024 0.024 0.024 Residual 5.042 4.695 4.695 4.692 4.695 4.695 N 39,653 32,290 32,290 32,290 32,290 32,290 Higher scores indicate a more positive attitude; *p<0.05, **p<0.01, ***p<0.001; sampling weights are considered; model 0 represents the null model, model 1 presents the coefficients (S.E.) of education with ISCED I as reference category and individual characteristics as control variables; model 2 adds contextual variables migrant inflow rate (model 2a) and unemployment rate (model 2b); model 3 adds the interaction of education and contextual variables (migrant inflow rate in model 3a and unemployment rate in model 3b); the complete table with a list of all individual-level control variables can be found in Table A6 in the appendix Table 7 Hierarchical, three-level, crossed-classified random effects models of economic attitudes toward immigration in 12 non-Eastern European countries Model 0 Model 1 Model 2a Model 3a Model 2b Model 3b Intercept 5.221 (0.109) *** 4.634 (0.111) *** 4.541 (0.126) *** 4.387 (0.127) *** 4.732 (0.137) *** 4.815 (0.139) *** Individual level Education (ref: ISCED I) ISCED II 0.397 (0.019) *** 0.397 (0.019) *** 0.527 (0.037) *** 0.397 (0.019) *** 0.324 (0.038) *** ISCED III 0.632 (0.018) *** 0.632 (0.018) *** 0.726 (0.033) *** 0.632 (0.018) *** 0.497 (0.038) *** ISCED IV 1.078 (0.022) *** 1.077 (0.022) *** 1.317 (0.041) *** 1.078 (0.022) *** 1.049 (0.045) *** ISCED V 1.657 (0.019) *** 1.657 (0.019) *** 1.924 (0.035)*** 1.657 (0.019) *** 1.507 (0.037) *** Country-period level Migrant inflow rate 0.109 (0.072) 0.318 (0.078)*** Unemployment rate − 0.013 (0.009) − 0.022 (0.009) * ISCED II x migrant inflows − 0.192 (0.043)*** ISCED III x migrant inflows − 0.155 (0.039)*** ISCED IV x migrant inflows − 0.317 (0.045)*** ISCED V x migrant inflows − 0.362 (0.041)*** ISCED II x unemployment 0.008 (0.004) * ISCED III x unemployment 0.015 (0.004) *** ISCED IV x unemployment 0.002 (0.005) ISCED V x unemployment 0.017 (0.004) *** Random effects: var Country (level 3) 0.111 0.124 0.121 0.12 0.143 0.142 Country-period (level2) 0.146 0.058 0.057 0.057 0.056 0.057 Country-cohort (level 2) 0.058 0.01 0.01 0.01 0.01 0.01 Residual 6.154 5.162 5.162 5.159 5.162 5.161 N 205,293 186,382 186,382 186,382 186,382 186,382 Higher scores indicate a more positive attitude; *p<0.05, **p<0.01, ***p<0.001; sampling weights are considered; model 0 represents the null model, model 1 presents the coefficients (S.E.) of education with ISCED I as reference category and individual characteristics as control variables; model 2 adds contextual variables migrant inflow rate (model 2a) and unemployment rate (model 2b); model 3 adds the interaction of education and contextual variables (migrant inflow rate in model 3a and unemployment rate in model 3b); the complete table with a list of all individual-level control variables can be found in Table A7 in the appendix Section title: Results of the analysis Educational score: 0.9699601531028748 Domain: other Document type: Other Language: en In sum, our results show that while education plays some liberalising and empowering role in shaping both cultural and economic attitudes, the association of contextual factors and attitudes toward immigrants varies between the two attitudes and across regions. Section title: Conclusion Educational score: 1.3216031789779663 Domain: other Document type: Study Language: en Previous research on attitudes toward immigration has repeatedly identified education as one of the most stable predictors, with higher levels of education being associated with more inclusive attitudes toward immigration. However, cross-national research on how contextual and regional factors determine attitudes toward immigration in Europe is scarce , especially considering the well-established link between education and immigration attitudes. This study aimed to help fill this gap by examining repeated cross-sectional data from 15 European countries over 16 years while considering socioeconomic changes, such as changes in unemployment rates and migrant inflow rates, as well as regional differences between Eastern European and non-Eastern European countries. Our main question was how these contextual and regional variations affect the role of education in shaping cultural and economic attitudes toward immigration. Section title: Conclusion Educational score: 1.6201621294021606 Domain: other Document type: Study Language: en Consistent with our expectations and previous research, we find supporting evidence for our first hypothesis—a robust positive and significant association between higher education and pro-immigration attitudes in both aspects between 2002 and 2018. The strength of this association, however, depends on contextual and regional factors. When examining the entire sample of 15 countries, our results reveal that higher migrant inflow rates attenuate the liberalising role of education in shaping cultural attitudes, lending support for the cultural threat explanation and refuting the first part of our second hypothesis. This finding challenges the generality of previous assumptions that the cognitive enhancement and broader thinking horizons associated with higher education make cultural attitudes toward immigration more liberal . Interestingly, the difference in economic attitudes between those with higher and lower levels of education—education’s liberalising role—also decreases with a greater influx of immigrants. While we did not expect a significantly larger gap in economic attitudes between higher and lower educated in our second hypothesis, our finding suggests a clear decline in education’s liberalising role. This could be because a larger influx of immigrants can be perceived as a fiscal burden on the welfare system and taxpayers among the higher educated . Section title: Conclusion Educational score: 0.8868642449378967 Domain: other Document type: Study Language: en Furthermore, greater economic hardship appears to decrease favourable economic attitudes toward immigration, while the liberalising role of education slightly increases with greater economic hardship. However, contrary to our expectations, there is no significant interaction between education and unemployment for cultural attitudes. Thus, we find supporting evidence for our third hypothesis with regard to economic attitudes but no evidence for cultural attitudes. Section title: Conclusion Educational score: 1.0189673900604248 Domain: other Document type: Study Language: en A look at the regional differences reveals an interesting dynamic. Consistent with previous research, we find that Eastern European countries have increasingly more negative attitudes toward immigration than their non-Eastern European counterparts . Specifically, our descriptive results show that of the three Eastern European countries in our sample, Slovenia and Hungary were the most anti-immigration in both aspects among the Eastern European countries and all 15 selected countries. This could be partially because these countries served as transit points for refugees coming to Europe during the 2015 immigration crisis and partly due to the official anti-refugee policy in Hungary , which led to an increased influx of refugees to Slovenia . Section title: Conclusion Educational score: 1.3287168741226196 Domain: other Document type: Study Language: en Furthermore, our descriptive results suggest that non-Eastern European countries are more susceptible to an economic rather than a cultural threat perception. In Eastern European countries, net attitudes are negative in terms of both cultural and economic aspects, with a particularly high susceptibility to economic threats. However, contrary to our expectations and previous research on general immigration attitudes , our findings indicate that higher unemployment rates are significantly positively associated with cultural attitudes in both regions but are significantly negative for economic attitudes only in non-Eastern European countries. Moreover, a larger influx of migrants reduces the liberalising role of education in shaping cultural attitudes in non-Eastern European countries but not in Eastern European countries, with a negative average net attitude. In addition, higher immigration rates have a significantly negative effect on the economic attitudes of lower-educated Eastern Europeans compared to higher-educated Eastern Europeans while reducing the liberalising role of education among non-Eastern Europeans. Finally, economic hardship increases the liberalising role of education in shaping economic attitudes in non-Eastern European countries but is not significant in Eastern European countries. Section title: Conclusion Educational score: 0.9425898194313049 Domain: other Document type: Study Language: en In sum, our results highlight regional differences in the role of contextual factors in shaping cultural and economic attitudes toward immigration. They corroborate previous research indicating that the relationships determining attitudes toward immigration in non-Eastern European countries do not necessarily apply to Eastern European countries . These differences may be attributed to the fact that Eastern European countries lived for decades under a highly restrictive socialist system with an explicitly internationalist ideology, which left little room for the development of national identities. This context urges more comparative research on the established relationship between education and attitudes toward immigration in the two regions. Section title: Conclusion Educational score: 1.0633466243743896 Domain: other Document type: Study Language: en Despite the merits of this study, we recognise its limitations. First, while we discuss the liberalising role of education in shaping cultural and economic attitudes toward immigration, we by no means imply causality, i.e., a direct effect, in this relationship. Thus, at best, we can report an association between higher education and positive or negative attitudes toward immigration in both aspects. Although recent studies engaging with causality in this relationship report somewhat conflicting results, they are an important endeavour to understand the direct mechanisms that influence individual attitudes toward immigration. We believe that further exploration of these mechanisms in different aspects of immigration attitudes in a larger number of countries will help to broaden our understanding of whether this relationship is indeed causal or circumstantial and how different contextual and regional factors influence the hypothesised causality. Section title: Conclusion Educational score: 1.0467658042907715 Domain: other Document type: Study Language: en Second, our selection of countries was determined by the availability of data, and three Eastern European countries are insufficient to draw overarching conclusions for the whole of Eastern Europe. However, the striking differences between the Eastern European and non-Eastern European countries in our sample justify a deeper scholarly interest in how the established relationship between education and immigration attitudes varies across what appear to be such disparate regions. There seems to be a consensus that higher education not only empowers people by providing them with the necessary skills to compete in the labour market but also helps them develop a more critical and liberal mind. This study, however, shows that this is not universal. We believe that future research engaging with this question, using different data sources and methodological techniques, will deepen our understanding of the role of regional differences. Section title: Supplementary Information Educational score: 1.1732151508331299 Domain: biomedical Document type: Other Language: it Additional file 1. | Other | other | en | 0.999997 |
PMC11698880 | Section title: Introduction Educational score: 4.5398101806640625 Domain: biomedical Document type: Study Language: en One of the most influential biological associations is the interrelationship between insects and plants. The evolutionary interplay between insects and plants, either as friends or foes, has shaped terrestrial ecosystems for at least the last 400 million years . Of the myriad ways in which these titans of biodiversity interact, none is more intimate than that of pollination, a mutualism, with some specialised exceptions, that has aided the proliferation of both lineages . Indeed, today insects are the primary pollinators for nearly 90 % of all flowering plants . Perhaps among all of these insect pollinators, none are more iconic than the bees, a specialised lineage of phytophagous stinging wasps that feed their larvae pollen and nectar . With over 20,500 species, bees are critical to the success of many terrestrial ecosystems through their pollination services and especially vital for agriculture and food security where there is a particular overreliance on honey bees (genus Apis Linnaeus). Over the last 120 million years, bees have evolved many specialisations for the gathering and processing of pollen, nectar, floral oils, and plant exudates . While most bees are polylectic, numerous lineages have evolved various degrees of host-plant specialisation (oligolecty) and, in rare instances, outright monolecty . While much intensity is devoted to the study of bee pollination, an understanding of the evolutionary history of this association has been restricted mainly to indirect inferences either through phylogenetic estimation or from isolated fossil occurrences. For example, the inference of orchid pollination in Miocene Hispaniola based on the presence of orchid bees in Dominican amber even in the absence of attached orchid pollinia . The history of insect pollination as documented by the fossil record is gaining momentum , particularly through the exploration of pollen grains preserved on or within insect fossils belonging to pollinating lineages and this has been especially true for the bees. Some of these exceptional fossils provide direct evidence of pollen collected by the bees during life and a glimpse into ancient insect-plant interactions . Section title: Introduction Educational score: 4.163806915283203 Domain: biomedical Document type: Study Language: en Here, we report the discovery of a large carpenter bee (genus Xylocopa Latreille) from the middle Eocene of Messel, Germany. Species of Xylocopa have been previously reported as compression fossils from various localities, nearly all of which are from the Miocene . A notable exception was the fragmentary Xylocopa gabrielae Engel from the Eocene-Oligocene boundary of Florissant, Colorado , hitherto the earliest occurrence of the genus. The new species reported here now supersedes X. gabrielae in age. Of significance, the new fossil has adhering pollen preserved on the body, allowing for an investigation into the floral visits of this individual immediately prior to death and providing a snapshot of bee-flower relationships during the Eocene. Direct evidence of floral visitation by fossil insects is exceptionally limited. We describe the xylocopine bee and its adhering pollen and explore the occurrences of the floral families represented and their modern insect visitors in relation to the discovery of their association with the bee documented herein. This is the first documentation of pollen from a fossil carpenter bee and only the third genus of bees from the Eocene in which adhering pollen has been recorded. Section title: Material and methods Educational score: 1.8044713735580444 Domain: other Document type: Study Language: en The Messel pit is located on the eastern side of the Rhine Rift Valley, about 8 km northeast of Darmstadt, Germany . The lacustrine sediments of the Messel Formation were deposited within a maar volcanic crater, which had a diameter of at least 1.5 km and an initial depth of 300–400 m . The sedimentary rocks have been dated as early middle Eocene (early Geiseltalian), with a radiometric age (Ar 40/39 ) determination of 47.8 ± 0.2 Ma from volcaniclastic sediments and 48.27–48.11 Ma ± 0.22 Ma from high-resolution palynological analyses . Current estimates based on astronomical tuning date the origin of sediment deposition to have occurred 48.06 million years ago . The fossils represent a diverse biota of exceptionally preserved microorganisms, plant organs, insects, fishes, amphibians, reptiles, birds, and mammals , inferred to represent a paratropical Eocene rainforest . The stratigraphy of the Messel pit has been briefly summarised in Wappler and Engel . Fig. 1 Geographical and geological maps of the Messel pit. a Location of the Messel pit in Germany. b Simplified geological map of the area surrounding the Messel pit . c Simplified sedimentary profile based on the Messel 2001 drill core . The fossil bee was collected 37 cm above local stratigraphic marker level M. d Panoramic overview of the Messel pit, X marks the site (grid square H13/14) where the bee was collected Section title: Material and methods Educational score: 1.827353835105896 Domain: biomedical Document type: Other Language: en The studied bee fossil is preserved in the collection by immersing the slab of oil shale in glycerine to prevent damage by desiccation . The described individual was observed and digitized using a Keyence VHX-7000 microscope, and all relevant structures were measured from the digitized images. All photographs were optimised using Adobe Lightroom CC. Drawings were made from the photographs using Affinity Designer (affinity.serif.com). Section title: Material and methods Educational score: 4.122390270233154 Domain: biomedical Document type: Study Language: en The fossil bee was examined and sampled for pollen according to the method described in Grímsson et al. . A stereomicroscope equipped with epifluorescence illumination was used to examine and photograph the fossil. Pollen grains were extracted from the head, metasoma, and legs of the bee and processed for combined light microscopy (LM) and scanning electron microscopy (SEM) analysis by bleaching followed by acetolysis . Pollen grains were investigated using the “single-grain method” by Zetter . Morphological terminology for the description of the bee follows Engel and Michener , and the classification of Xylocopa follows Michener . The classification of plants follows that of the APG IV , with pollen of Theaceae described first, followed by the Araliaceae. Pollen descriptions include all features observed with both LM and SEM. The pollen terminology follows Punt et al. and Halbritter et al. . Taxonomic actions made herein are registered in ZooBank ( www.zoobank.org ) with the article LSID: urn:lsid:zoobank.org:pub:3B66630B-F719-4A16-ABC6-FF2DB08907CE Section title: Systematic palaeontology Educational score: 1.1435534954071045 Domain: biomedical Document type: Other Language: et Kingdom Animalia Linnaeus, 1735 Section title: Systematic palaeontology Educational score: 2.0693042278289795 Domain: biomedical Document type: Other Language: en Phylum Arthropoda Gravenhorst, Siebold, 1848 Section title: Systematic palaeontology Educational score: 1.3190284967422485 Domain: biomedical Document type: Other Language: en Class Insecta Linnaeus, 1758 Section title: Systematic palaeontology Educational score: 1.9254603385925293 Domain: biomedical Document type: Other Language: de Order Hymenoptera Linnaeus, 1758 Section title: Systematic palaeontology Educational score: 1.2650278806686401 Domain: other Document type: Other Language: en Family Apidae Latreille, 1802 Section title: Systematic palaeontology Educational score: 1.2542368173599243 Domain: other Document type: Other Language: it Tribe Xylocopini Latreille, 1802 Section title: Systematic palaeontology Educational score: 1.6327002048492432 Domain: other Document type: Other Language: ca Genus Xylocopa Latreille, 1802 Section title: Systematic palaeontology Educational score: 1.8559050559997559 Domain: other Document type: Other Language: en Apocolyx Engel subgen. nov. Section title: Systematic palaeontology Educational score: 1.5049562454223633 Domain: other Document type: Other Language: en Type species ( hic designatus ): Xylocopa ( Apocolyx ) primigenia Engel and Wappler sp. nov. Section title: Systematic palaeontology Educational score: 4.246772766113281 Domain: biomedical Document type: Study Language: en Diagnosis: It is challenging to compare the current fossil with modern relatives in many characters traditionally employed in the classification of Xylocopa (e.g. facial carinae, form of metabasitibial plate, sternal and tergal graduli, pygidial plate). Nonetheless, there are sufficient details to make some important distinctions, most notably in the forewing venation. The new subgenus differs from all other groups of Xylocopa by the much shorter and broader marginal cell that tapers away from the anterior wing margin near its base and ends at about the apex of the third submarginal cell, rather than that of the living subgenera in which the cell is noticeably slender, elongate, extends well beyond the third submarginal cell, and tapers away from the anterior wing margin in its apical third or quarter. In addition, the second submarginal cell, while having the usual asymmetrical trapezoidal shape of most Xylocopa species, is quite exaggerated in its proximal extension and narrow anterior margin, with the posterior margin over 10× greater than the anterior margin (this is usually over 2× in most extant Xylocopa but never exceeds 4.5× the length). Additional features of the subgenus include: 2rs-m prominently bowed apically (as in most extant subgenera); given the orientation of the longitudinal axis of the compound eye relative to the vertex it would seem that the eyes do not converge above or below, as in the subgenera Xylocopoda Hurd and Moure and some species of Xylomelissa Hurd and Moure ; the mesal margin of the compound eye is weakly incurved, as in many subgenera of Xylocopa ; the vertex is straight before arching laterally above the compound eye, as is the case in various subgenera; the median ocellus is slightly smaller than the antennal torulus, as is the case in most Old World subgenera; the mesoscutellum is not flattened nor projecting over the metanotum. Section title: Systematic palaeontology Educational score: 2.9538075923919678 Domain: biomedical Document type: Study Language: en It would be easy to consider the species reported herein as generically distinct from Xylocopa owing to the unique marginal cell and more exaggerated second submarginal cell, but given the greater number of similarities to modern large carpenter bees (e.g. elongate metabasitarsus, trapezoidal second submarginal cell, virtually absent pterostigma, proximally constricted marginal cell, large body size, papillate wing membrane beyond veins) we have conservatively considered the fossil to belong to a putatively early-diverging subgenus. Section title: Systematic palaeontology Educational score: 1.240853190422058 Domain: other Document type: Other Language: en Etymology: The new genus-group name is an anadrome of Xylocopa Latreille. The gender of the name is considered to be feminine. The subgeneric name is registered under ZooBank LSID urn:lsid:zoobank.org:act:0BBDAFBE-130F-4EC4-8E5E-8B8E49DC27A7. Section title: Systematic palaeontology Educational score: 1.7565861940383911 Domain: other Document type: Other Language: en Xylocopa ( Apocolyx ) primigenia Engel and Wappler sp. nov. Section title: Systematic palaeontology Educational score: 1.846567988395691 Domain: other Document type: Other Language: en Fig. 2 Messel large carpenter bee, Xylocopa ( Apocolyx ) primigenia subgen. et sp. nov., holotype female. a, b Photograph of entire specimen and line drawing of pertinent sclerites; c, d Photograph of forewing and line drawing of preserved and reconstructed venation. Scales 2 mm; yellow asterisk Theaceae pollen extraction area; orange asterisk Araliaceae pollen extraction area Section title: Systematic palaeontology Educational score: 1.3924038410186768 Domain: other Document type: Other Language: en Diagnosis: As for the subgenus ( vide supra ). Section title: Systematic palaeontology Educational score: 4.255488395690918 Domain: biomedical Document type: Study Language: en Description: ♀: Total body length (as preserved, apical metasomal segments missing so length in life would have been much longer) 17.68 mm; forewing length ~15.08 mm, maximum width 4.66 mm; integument dark brown to black as preserved, sculpturing not discernible as preserved. Head broader than long, medial length 3.92 mm, width (as preserved) 3.99 mm; compound eye length 2.94 mm, mesal margin of compound eye weakly incurved; vertex straight. Mesosoma length 5.62 mm (as preserved, apical portion of propodeum missing), maximum width 5.34 mm; mesoscutum length 3.66 mm, mesoscutellum length 1.11 mm; mesoscutellum not flattened nor extending posteriorly over metanotum (i.e. not as in Koptortosoma Gribodo or Mesotrichia Westwood), seemingly low and slightly rounded. Forewing prestigma virtually absent; pterostigma virtually absent owing to absence of abscissa of R between r-rs and anterior wing margin; r-rs elongate, angling posteriorly from apex of R to meet 2Rs; R nearly immediately diverging from anterior wing margin (i.e. in proximal portion of marginal cell) to point near tangent with apex of third submarginal cell, then steeply angling posteriorly to meet Rs; apex of marginal cell feebly appendiculate; marginal cell comparatively broad, nearly as wide as third submarginal cell (presumed plesiomorphy; in extant subgenera apical portion of marginal cell 0.5× width or less of third submarginal cell), marginal cell not extending well beyond apex of third submarginal cell (unique apomorphy; marginal cell extending well beyond apex of third submarginal cell in extant subgenera); 1Rs and 1M forming a straight line; 1M nearly confluent with 1cu-a; 1cu-a orthogonal to M+Cu and A; Rs+M comparatively short, slightly less than one-third length of 2M; 2Rs elongate, meeting r-rs close to 1rs-m; 1rs-m straight, approximately orthogonal to Rs, slightly basad 1m-cu; second submarginal cell strongly asymmetrically trapezoidal, with posterior margin more than 10× anterior margin (unique apomorphy); 1m-cu and 2m-cu both entering third submarginal cell, former near base of cell, latter slightly distad cell midlength; third submarginal cell large, much longer than wide; 2rs-m strongly bowed outward; 2Cu with enigmatic posterior bend before origin of 2m-cu (unclear whether this may be an artifact); wing membrane beyond veins papillate. Hind wing with 1Rs straight, 2Rs elongate and weakly arched; rs-m slightly less than 0.5× length 1Rs; 1M slightly longer than 1Rs, slightly more than 2× as long as 2M; 2M comparatively short, slightly longer than rs-m; 1Cu shorter than 1M; 2M+Cu about as long as 1M. Metabasitarsus elongate (as is typical for Xylocopa ), distinctly longer than combined lengths of remaining tarsomeres and probably longer than metatibia, length 3.75 mm, densely setose. Metasoma broad, wider than mesosoma, width 7.72 mm (as preserved across tergum II). Section title: Systematic palaeontology Educational score: 1.0862305164337158 Domain: other Document type: Other Language: no ♂: Latet . Section title: Systematic palaeontology Educational score: 1.0293152332305908 Domain: other Document type: Other Language: en Holotype ( hic designatus ): ♀, HLMD-Me-15783, deposited in the Hessisches Landesmuseum, Darmstadt, Germany. Section title: Systematic palaeontology Educational score: 0.9361875057220459 Domain: other Document type: Other Language: en Type locality and horizon: Messel pit (latitude 49°55′N, longitude 8°45′E) near Darmstadt, Hesse, Germany; Messel Formation, lower mid-Eocene, Geiseltalian, ca. 48 Ma. The specimen was collected in 1997 in grid square H13/14, in strata 37 cm above local stratigraphic marker level M. Section title: Systematic palaeontology Educational score: 1.101851224899292 Domain: other Document type: Other Language: en Etymology: The specific epithet is the Latin adjective primigenius , meaning, “firstborn”, “original”, or “primitive”. The specific epithet is registered under ZooBank LSID urn:lsid:zoobank.org:act:80EECF13-F03C-4873-AC1B-C350A433FB95 Section title: Systematic palaeontology Educational score: 1.079293131828308 Domain: other Document type: Other Language: sv Kingdom Plantae Haeckel, 1866 Section title: Systematic palaeontology Educational score: 1.5799134969711304 Domain: other Document type: Other Language: it Angiospermae Section title: Systematic palaeontology Educational score: 1.0445197820663452 Domain: other Document type: Other Language: de Order Ericales Bercht. and J.Presl, 1820 Section title: Systematic palaeontology Educational score: 1.65713369846344 Domain: biomedical Document type: Other Language: en Family Theaceae Mirb., 1816 Section title: Systematic palaeontology Educational score: 1.3581615686416626 Domain: biomedical Document type: Other Language: nl Theaceae gen. et sp. indet. Section title: Systematic palaeontology Educational score: 4.0733489990234375 Domain: biomedical Document type: Study Language: en Fig. 3 Light microscopy (LM) ( a, d, g, j, m, p ) and scanning electron microscopy (SEM) ( b, c, e, f, h, i, k, l, n, o, q, r ) micrographs of fossil Theaceae and Araliaceae pollen extracted from the fossil carpenter bee ( Xylocopa primigenia sp. nov.). a–l Theaceae pollen extracted from the head ( a–f ) and the metasoma ( g–l ); m-r Araliaceae pollen extracted from the mid leg; a Theaceae pollen in polar view; b same gain as in a; c detail of colpus membrane; d Theaceae pollen in polar and equatorial view; e same grain as in e; f detail of polar area and adjacent colpus; g Theaceae pollen in polar view; h same gain as in g; i detail of mesocolpium; j Theaceae pollen in polar view and equatorial view; k same grain as in j; l detail of the bridge covering the porus; m Araliaceae pollen in polar view and equatorial view; n same grain as in m; o detail of the aperture; p Araliaceae pollen in polar view and equatorial view; q same grain as in p; r detail of polar area. Scales = 10 µm ( a, b, d, e, g, h, j, k, m, n, p, q ), 1 µm ( c, f, i, l, o, r ) Section title: Systematic palaeontology Educational score: 1.8958910703659058 Domain: biomedical Document type: Other Language: en Note: Pollen extracted from head and metasoma Section title: Systematic palaeontology Educational score: 4.047389030456543 Domain: biomedical Document type: Study Language: en Description: Pollen, monad, prolate, outline convex-triangular to circular in polar view, elliptical in equatorial view; polar axis 20–24 µm in LM, 17–22 µm in SEM, equatorial diameter 15–24 µm in LM, 15–21 µm in SEM; tricolporate, endoporus lalongate and weakly outlined, colpi 3/4 of polar axis long (SEM), nexine thickened along colpi towards endoapertures, colpus membrane granulate to microareolate, bridge over porus; exine 1.1–1.7 µm thick (LM), sexine and nexine equally thick; sculpture scabrate in LM, microreticulate, rugulate, fossulate, and perforate in SEM, occasional granulate suprasculture (SEM). Section title: Systematic palaeontology Educational score: 4.295660018920898 Domain: biomedical Document type: Study Language: en Remarks: The current circumscription of Theaceae comprises approximately 367 species in eight genera . To our knowledge there currently exists no comprehensive palynological work on pollen from extant Theaceae and only a small portion of the species have been investigated palynologically. Still, selective taxa from all genera have been published, either using only LM or SEM, combined LM and SEM, or combined SEM and TEM . Based on the combined features observed in the fossil pollen grains we are able to assign this pollen type to Theaceae, but not with certainty to any extant genus. The general size, outline and shape, as well as the aperture configuration in LM is similar between pollen of extant genera. The thickening of the nexine around the apertures observed with LM, as observed in the fossil pollen, is prominent in some species of Camellia L. . The sculpture of the fossil pollen observed with SEM is most comparable to that of pollen from extant Camellia , Schima Reinw. ex Blume, and Stewartia L. . Based on the available information from pollen morphology and ultrastructure of extant Theaceae it is most conservative to state that the fossil pollen is an morphological intermediate type between the three aforementioned genera and could be affiliated with any of them, but see fossil record below. Table 1 Numbers of extant genera and species of Theaceae and Araliaceae. Note: Generic names and species numbers compiled from POWO Theaceae Species Araliaceae Species Apterosperma Hung T.Chang 1 Hedera L. 19 Camellia L. 230 Heptaleurum Gaertn. 321 Franklinia W. Bartram ex Marshall 1 Heteropanax Seem. 9 Gordonia Ellis 22 Hydrocotyle Tourn. ex L. 177 Polyspora Sweet 49 Kalopanax Miq. 1 Pyrenaria Blume 27 Macropanax Miq. 18 Schima Reinw. ex Blume 16 Merrilliopanax H.L.Li 3 Stewartia L. 22 Meryta J.R.Forst. and G. Forst. 27 Metapanax J.Wen and Frodin 2 Araliaceae Species Motherwellia F.Muell. 1 Anakasia Philipson 1 Neocussonia Hutch. 16 Aralia L. 73 Neopanax Allan 5 Astropanax Seem 15 Oplopanax (Torr. and A.Gray) Miq. 3 Astrotricha DC. 20 Oreopanax Decne. and Planch. 146 Brassaiopsis Decne. and Planch. 46 Osmoxylon Miq. 61 Cephalaralia Harms 1 Panax L. 14 Cephalopanax G.M.Plunkett, Lowry & D.A.Neill 2 Plerandra A. Gray 33 Cheirodendron Nutt. ex Seem 6 Polyscias J.R. and G.Frost 180 Chengiopanax C.B.Shang & J.Yhuang 2 Pseudopanax K.Koch 7 Crepinella Marchal 33 Raukaua Seem. 6 Cussonia Thinb. 20 Schefflera J.R.Frost. and G.Frost. 13 Dendropanax Decne. & Planch. 95 Sciodaphyllum P.Browne 145 Didymopanax Decne. & Planch. 38 Sinopanax H.L.Li 1 Eleutherococcus Maxim. 29 Tetrapanax (K.Koch) K.Koch 1 Fatsia Decne. & Planch. 3 Trachymene Rudge 59 Frodinia Lowry & G.M.Plunkett 2 Trevesia Vis. 8 Gamblea C.B.Clarke 4 Seemannaralia R.Vig. 1 Harmsiopanax Warp. 3 Woodburnia Prain 1 Section title: Systematic palaeontology Educational score: 1.7179481983184814 Domain: biomedical Document type: Other Language: de Order Apiales Nakai, 1930 Section title: Systematic palaeontology Educational score: 1.5777605772018433 Domain: biomedical Document type: Other Language: en Family Araliaceae Juss., 1789 Section title: Systematic palaeontology Educational score: 1.678640604019165 Domain: biomedical Document type: Other Language: nl Araliaceae gen. et sp. indet. Section title: Systematic palaeontology Educational score: 1.8522248268127441 Domain: biomedical Document type: Other Language: en Note: Pollen extracted from mid leg Section title: Systematic palaeontology Educational score: 4.065032958984375 Domain: biomedical Document type: Study Language: en Description: Pollen, monad, prolate, outline triangular to tri-lobate in polar view, lens-shaped to elliptic in equatorial view; polar axis 19–31 µm in LM, 23–27 µm in SEM, equatorial diameter 16–30 µm in LM, 17–25 µm in SEM; tricolporate, endoporus large and lalongate, colpus 2/3 of polar axis (SEM), massive nexine thickening along apertures (up to 3 µm thick in LM); exine 1.1–1.8 µm thick (LM), sexine as thick or thicker than nexine; sculpture reticulate in LM and SEM, reticulum gradually decreasing in size from polar areas and mesocolpium towards colpi, forming a perforated and psilate margin along colpi (SEM). Section title: Systematic palaeontology Educational score: 4.210483074188232 Domain: biomedical Document type: Study Language: en Remarks: Araliaceae are a large family, currently comprising about 1680 species in 46 genera . There are several publications on the pollen morphology (LM, SEM) and ultrastructure (TEM) of Araliaceae pollen . Based on the combined morphological traits (incl. size, shape, reticulate sculpture, exine thickness, thickened nexine around apertures, and lalongate endopori) observed with combined LM and SEM we assign this pollen type to the Araliaceae. However, pollen of species and genera of Araliaceae often overlap in most diagnostic morphological LM and SEM based features. Members of Dendropanax Decne. and Planch. , Eleutherococcus Maxim. , Heteropanax Seem. , Macropanax Miq. , Merrilliopanax H.L.Li , Metapanax J.Wen and Frodin , Neopanax Allan , Polyscias J.R.Forst. and G.Forst., and some of Schefflera J.R.Forst. and G.Forst. and Tetrapanax (K.Koch) K.Koch are more likely to be the parent plants of the fossil araliaceous pollen. Others, including Aralia L., Didymopanax Decne. and Planch., Dendropanax , Kalopanax Miq. , and some members of Panax L. and Schefflera have ambivalent morphologies. Only a few genera, including Brassaiopsis Decne. and Planch. , Fatsia Decne. and Planch. , Hedera L., Oplopanax (Torr. and A.Gray) Miq. , Osmoxylon Miq. , Panax L., and Trevesia Vis, exhibit differences in pollen morphology that allow for them to be excluded as the potential parent plant of the fossil araliaceous pollen type. Therefore, this fossil pollen type could consequently belong to several extant genera, but see fossil record below. Section title: Fossil record of parent plants – match or mismatch with the Messel flora? Educational score: 4.226300239562988 Domain: biomedical Document type: Study Language: en The fossil record of Theaceae dates back to the Upper Cretaceous with scarce findings of Pollenites pollen ( Gordonia Ellis and Schima type) from Alabama, U.S.A. ; Palaeoschima seeds ( Schima like) from Germany, Austria, and Czechia ; and Schimoxylon wood (similar to Schima ) from Egypt . Most other Cretaceous records have been rejected or are considered doubtful by Grote and Dilcher . Cenozoic records are numerous, including both extinct genera like Andrewisocarpon and Gordoniopsis as well as extant representatives of Camellia , Gordonia , Polyspora Sweet, Schima , and Stewartia . Even though Paleocene fossils of Theaceae are more or less absent, other Paleogene records, especially of Eocene age, show that the family had already diverged and dispersed across the globe during that time. Camellia (and alike) fossils have been reported from the middle Eocene of Germany ; the late Eocene of Honshu, Japan ; the early Oligocene of Washington, U.S.A and Bulgaria ; and the late Oligocene of Nanning, South China . Fossils of Gordonia are documented from the middle Eocene of Kentucky and Tennessee U.S.A ; the middle to late Eocene of Germany ; the late Eocene of England ; and the Oligocene of Japan . Fossils of Polyspora have been reported from the middle to late Eocene of Germany and the late Eocene of Czechia . Schima (and alike) fossils are known from the middle Eocene of Germany , the middle Eocene of Myanmar , and the late Oligocene of Guangxi, China . The Theaceae pollen type reported herein is not the first representative of this family from the Messel pit. Wilde described from this locality leaves of Polyspora and Collinson et al. fruit of Camelliacarpoidea (similar to Camellia ). Considering these two records as well as other Eocene fossils of Theaceae reported from Germany , it is likely that the fossil theaceous pollen belongs to one of the following genera: Camellia , Gordonia , Polyspora , or Schima . Section title: Fossil record of parent plants – match or mismatch with the Messel flora? Educational score: 4.328456878662109 Domain: biomedical Document type: Study Language: en The early fossil pollen records of Araliaceae extend back to the Upper Cretaceous (lower Campanian) of Wyoming, U.S.A.; Upper Cretaceous (Senonian) of China; the Paleocene and Eocene of Greenland; the Eocene of western North America; and the Paleocene (France) and Eocene (Germany) of Europe . Early macrofossil records include fruit/seeds of Acanthopanax (Decne. and Planch.) Witte (now within: Eleutherococcus Maxim.) and Aralia from the Upper Cretaceous (Maastrichtian) of Germany , flowers of Tetraplasandranthus from the Upper Cretaceous/Eocene of India , araliaceous wood ( Plerandreoxylon ), fruits ( Paleopanax ; similar to Pseudopanax ), and leaves from the middle Eocene of Oregon, U.S.A. , and leaves of Dendropanax from the middle Eocene of Tennessee . As with the Theaceae, the fossil record of Araliaceae suggests that the family had already dispersed around the globe prior to the end-Eocene and was represented by a number of extinct and extant genera by that time. Oligocene records include mostly fossils assigned to extant genera, such as Aralia (now incl. Pentapanax Seem.) and Schefflera from Germany . Fossils of Araliaceae from Messel are rare and restricted to cuticle remains of cf. Fatsia and two Araliaceoipollenites pollen taxa . Dispersed pollen assigned to the larger subspecies of A. euphorii from Messel is probably the same pollen type (shared parent plant/taxon) as the Araliaceae pollen extracted from the fossil bee. As to date, no flower containing this pollen type is described from Messel, leaving a more precise affiliation pending. Considering the morphology of the fossil pollen and extant Araliaceae genera that have been documented in Europe in the Eocene-Oligocene, it is possible that the araliaceous pollen type from the bee originates from Schefflera . Section title: Pollination ecology of Theaceae and Araliaceae Educational score: 4.244765758514404 Domain: biomedical Document type: Study Language: en Knowledge about the pollination biology of Theaceae is meagre and only a few species have been investigated thoroughly. Among all genera, Camellia is the most studied due to its economic importance for both tea and oil production . Camellia sinensis (L.) Kuntze shows floral morphologies of a generalist pollination syndrome and is visited and pollinated by various animals including short-tongued flies, bees and wasps, beetles, moths, butterflies, and true bugs . For C. pubipetala Y.Wan and S.Z.Huang the primary pollinators are sun birds ( Aethopyga christinae Swinhoe) and honey bees ( Apis cerana Fabricius). During nectar feeding both sunbirds and bees come into contact with male and female reproductive organs of the flowers and are covered with pollen. Observations show that birds have pollen on their beaks and heads, while bees carry pollen on their entire body including mouthparts, metasoma, and legs . Flowers of C. oleifera C.Abel are also visited by a number of insects, especially bees and flies but also wasps. Bee visitors include cultivated honey bees ( A. cerana and A. mellifera L.) as well as wild bees ( Colletes gigas Cockerell , Andrena striata Fabricius , A. camellia Wu , A. hunanensis Wu , A. chekiangensis Wu). Flies that visit flowers of C. oleifera belong to the Calliphoridae, Muscidae, Sarcophagidae, and especially hover flies (family Syrphidae). The only wasp observed visiting C. oleifera flowers was Vespa velutina Lepeletier . Camellia japonica L. is also visited by song birds (among others, Zosterops erythropleura erythropleura Swinhoe), honey bees ( A. cerana and A. mellifera ), syrphid hover flies, and even a squirrel has been observed visiting the flowers . Flowers of C. sasanqua Thunb. are visited by birds, wasps, syrphid flies, moths, butterflies, and colletid bees . Gordonia lasianthus (L.) Ellis is visited by small beetles, ants, and halictid bees , while flowers of Schima superba Gardner and Champ. are visited by A. cerana and scarab beetles ( Protaetia brevitarsis (Lewis) and Popillia mutans (Newman)) . Schima wallichii (DC.) Korth. primary pollinators are honey bees ( Apis L.), carpenter bees ( Xylocopa ), and butterflies ( Sinthusa nasaka (Horsfield) , Cabera pusaria (L.), and Dysphania militaris (L.)) . Based on the currently available literature on flower visitations and pollinators of Theaceae it is clear that the family is animal pollinated and insects are the most common pollinators. Bees and flies seem to be the most frequent visitors/pollinators, followed by beetles and butterflies. Extant species of Xylocopa are important generalist pollinators in tropical, subtropical, and warm temperate regions and visit species of Theaceae, especially the flowers of Schima . Xylocopa ( Nyctomelitta ) tranquebarica (Fabricius) is known to visit Theaceae, and X. ( Biluna ) nasalis Westwood collects pollen of Schima that is fed to the larvae . Section title: Pollination ecology of Theaceae and Araliaceae Educational score: 4.053508758544922 Domain: biomedical Document type: Study Language: en Extensive studies on the pollination ecology of Araliaceae are lacking. In general, Araliaceae are pollinated primarily by insects, which are attracted by both nectar and pollen as rewards. Pollinators include flies (Bombyliidae, Calliphoridae, Muscidae, Syrphidae), bees and wasps (Apidae, Formicidae, Halictidae, Ichneumonidae, Vespidae), butterflies (Nymphalidae, Tortricidae), and beetles (Scarabeidae). Bird and bat pollination are also encountered, but are rare . Aralia hispida Vent. is probably pollinated by bumble bees . The pollinators of Eleutherococcus trifoliatus (L.) S.Y.Hu include flies of the families Syrphidae and Tachinidae, as well as honey bees ( Apis ) . Hedera helix L. is visited by about 20 taxa of insects. Wasps seemed to be important pollinators, next to honey bees, bumble bees, bristle flies, as well as small and large hover flies . Both Panax quinquefolius L. and P. wangianus S.C.Sun are visited by syrphid flies and halictid bees . Flowers of Polyscias pancheri (Baill.) Harms are visited by nomiine bees ( Austronomia sicheli (Vachal)), wasps (unidentified), scarab beetles ( Heteronyx caledoniae Fauvel), as well as ants that feed on nectar ( Polyrhachis guerini Roger) . Schefflera heptaphylla Z.H.Tsi floral visitors comprise primarily flies ( Chrysomya Robineau-Desvoidy and Syrphinae Latreille) and wasps ( Vespula Thomson and Eumenes Latreille) . Section title: Pollination ecology of Theaceae and Araliaceae Educational score: 4.283560276031494 Domain: biomedical Document type: Study Language: en The limited data on floral visitors and pollinators of Theaceae and Araliaceae are certainly consistent with the observation of bee visitation during the Eocene. The genus Xylocopa belongs to the same family (Apidae), as honey bees and bumble bees, albeit quite distantly related within that clade, and includes largely polylectic bees, some of whose species are today known to visit at least theaceous flowers, and likely also those of the Araliaceae. It is clear from the areas of localization of pollen on the fossil bee that early large carpenter bees were potential pollinators of flowers for both of these plant families in the local environment of Messel during the Eocene . Today species of Xylocopa transport pollen in often small loads on their legs (principally the metatibia and metabasitarsus), moving the pollen to the hind legs from the fore- and midlegs, and therefore with pollen occurring on all legs to some degree. In addition, species of Xylocopa are capable of buzz pollination whereby the sonicate flowers to dislodge pollen on to their venter, including the metasoma, and then use the legs to redistribute the pollen to their legs . Poricidal anthers necessitating buzz pollination are rare in Theaceae and Araliaceae and it is unlikely the Eocene species necessitated sonication to dislodge pollen. The heads of bees are also often covered with pollen when entering the corolla. Thus, the locations of the pollen on the fossil are consistent with modern species of Xylocopa visiting flowers for pollen and nectar . Since we discovered pollen from two completely different angiosperm families we assume a polylectic behaviour for the fossil Xylocopa bee. The family Apidae is well represented at Messel, with various species of the extinct genera Electrapis Cockerell and Protobombus Cockerell , both of which were also found to have visited a variety of flowers, including Araliaceae from Messel . However, it is possible that some were oiligolectic as suggested by the eucerine bee (Eucerini; a tribe with numerous oligolectic species) record from Messel . Unfortunately, it is not yet possible to make a comparison of pollen collection by fossil xylocopine bees as X. primigenia is the first extinct species of its subfamily to have been documented with adhering pollen. Fossils of Xylocopinae are rare and most were described long ago necessitating the location of historical type specimens to explore for potential pollen. For at least those species of Xylocopa described from the mid-Miocene of Öhningen, Germany no pollen was located on material preserved at ETH Zürich, Switzerland (M.S.E. pers. obs.). Only through greater sampling of potential pollinating insects from Messel and documentation of their associated pollen will permit a fuller understanding of the ecology of this ancient ecosystem. Fortunately, the exceptional preservation of fossils at Messel makes this an ideal locality from which to build such a comprehensive picture of flower-pollinator interrelationships from the Eocene. | Study | biomedical | en | 0.999995 |
PMC11698920 | Section title: Introduction Educational score: 4.206117630004883 Domain: biomedical Document type: Study Language: en Subject-specific finite element (FE) analysis of the mandible bone is one of the most recent advancements in biomechanics and craniomaxillofacial field and has increasingly gained attention, specifically in the field of implant design and bone-implant interaction analysis [ , , , , ]. Alongside geometry preparation, mesh generation, and boundary conditions, the material properties are one of the main parameters influencing the accuracy of FE analysis, as they are an integral part of the stiffness matrix . Despite the common use of homogeneous material properties for the mandible bone , a critical step for subject-specific FE modeling is the heterogeneous material modeling . This refers to the process of assigning appropriate physical and material properties, density and Young's modulus, to different anatomical areas of the bone within a computational model. Incorporating heterogeneous material properties of bone is particularly crucial in cases where bone quality should be respected e.g., for modeling osteoporotic mandibles , age-related changes in bone properties , tumors-related surgery , bone fractures and osteosynthetic treatment , bone reconstruction , and temporomandibular joint replacements . In this context, the primary method employed revolves around mathematical equations that correlate Hounsfield units from computed tomography (CT) and digital imaging and communications in medicine (DICOM) databases to both bone density and Young's modulus. Section title: Introduction Educational score: 4.0559468269348145 Domain: biomedical Document type: Study Language: en However, different material models proposing a relationship between density and Young's modulus show considerably varied material behavior. In this context, there has been no consensus on the reliability of such density-modulus relationships for the mandible bone , which makes comparison of different FE studies difficult . Hussein et al. used four different material models for mandible material properties and studied bone-implant interaction. Their comparative findings underscore the unreliability of results when employing heterogeneous bone material properties derived from different density-modulus relationships. Additionally, most of the available material models are primarily proposed for other bones e.g. femur or tibia and may not accurately model the relationship of density and Young's modulus of the mandible bone . Section title: Introduction Educational score: 3.9438350200653076 Domain: biomedical Document type: Review Language: en Therefore, the present study aims to review studies employing heterogeneous material modeling of the human mandible bone, to synthesize these models, investigate their origins, and assess their quality. This may help researchers in the craniomaxillofacial field in more accurately selecting material models for constructing subject-specific FE models of the mandible bone. Section title: Materials and methods Educational score: 4.0594377517700195 Domain: biomedical Document type: Review Language: en A systematic review was conducted on FE studies of the mandible that used heterogeneous material to model bone mechanical properties. This systematic review identified the most frequently applied material models. Furthermore, an extended search was performed to summarize and review all original studies referenced by these FE studies that proposed a density-modulus relationship. This involved examining the original studies to understand the methodologies and assumptions underlying the heterogeneous material models and assessing the risk of bias. Section title: Systematic review Educational score: 3.240828275680542 Domain: biomedical Document type: Review Language: en The systematic literature review was done according to the preferred reporting items for systematic reviews and meta-analyses guidelines . Section title: Literature search strategy Educational score: 4.09216833114624 Domain: biomedical Document type: Study Language: en Literature searches were conducted on studies published prior to 11 th October 2023 across electronic databases, including Scopus, PubMed, and Web of Science. The search strategy was constructed by combining relevant terms and Boolean operators. These terms were derived from the titles, abstracts, and keywords indexing of 10 known and relevant studies and categorized into the following three fields of interest. This search string was examined by authors several times in a back-and-forth manner to find the optimum studies in terms of number of the studies and range of the field of studies and was used to search within article title, abstract, and keywords. The Boolean operator AND was chosen to combine the search terms and create a search string. • Anatomical site of interest : (mandibular OR mandible OR temporomandibular OR "masticatory system") • Modeling strategy : "finite element" AND biomech∗ • Metrics of interest : (Hounsfield OR density OR ((young∗ OR elastic) AND modu∗) OR elasticity OR heterogeneous OR ((patient OR subject) AND (specific OR personali∗)) OR ((material OR mechanical) AND propert∗)) Section title: Literature search strategy Educational score: 1.8838261365890503 Domain: biomedical Document type: Study Language: en In addition, a random and unstructured hand search was performed based on the experience of the authors. The list of references of the included articles was also explored for relevant studies. Finally, the database search was updated on 1 st July 2024 before the manuscript submission with the same search method. Section title: Inclusion and exclusion criteria Educational score: 3.759810447692871 Domain: biomedical Document type: Review Language: en Several criteria were considered to include studies in this systematic review: (A) studies that explicitly stated their density-modulus relationship. This was done either by proposing the relationship or by clearly citing the original study describing the material model, and (B) only FE studies conducted on the mandible bone were included and considered valid for this review. Section title: Inclusion and exclusion criteria Educational score: 3.8009870052337646 Domain: biomedical Document type: Review Language: en Also, five criteria were considered for excluding the studies from this review: (a) non-English studies, (b) studies with a homogenous definition for the bone, (c) studies proposing density-modulus relationship, which require extra information on bone tissue that cannot be provided by conventional CT or cone beam computed tomography scanners, (d) animal studies, because of differences in the mechanical properties of the bone between human and animal mandibles, and (e) studies with no full text available for review. Section title: Selection and evaluation of studies Educational score: 3.9785091876983643 Domain: biomedical Document type: Study Language: en Three independent scientists (authors A-K. B., I. S., J-O. S.) first screened the abstract and title and afterward carefully reviewed each study to ensure its comprehensiveness and eligibility and extracted the density-modulus relationships explicitly mentioned in the respective study. All relevant articles were evaluated, and those that did not fit the study's inclusion criteria were excluded. Inconsistencies over the inclusion or exclusion of a study were debated by authors until a decision was reached by consensus. In addition to the material model used, the following information was extracted from the studies: the aim of the study, material assignment toolboxes, year of publication, working group/university, and whether a full mandible bone or a block of mandible bone was used in their FE analysis. Section title: Data extraction Educational score: 3.18060040473938 Domain: biomedical Document type: Study Language: en The included FE studies can be synthesized according to the employment of various density-modulus relationships. The origin of these material models was investigated, and the test conditions, determination coefficient (R 2 ), and sample characteristics (bone site and domain, sizes, and geometries) were evaluated and tabulated for the original studies. Section title: Quality assessment Educational score: 4.100125789642334 Domain: biomedical Document type: Study Language: en As per PRISMA guidelines, assessing the quality of the original studies, representing the study syntheses, gives insight into the study's credibility by identifying potential biases . Because the original studies included two distinct types of research, separate evaluation scales, tailored to each type, were employed. The Quality Assessment Tool for In vitro Studies, the so-called QUIN Tool offers a standardized method for evaluating the individual risk of bias for in vitro studies . This was carried out for all original studies that conducted in vitro experiments. The risk of bias for original studies based on FE simulations was assessed using the risk of bias tool for the use of finite element analysis in dentistry, the so-called ROBFEAD . Section title: Quality assessment Educational score: 3.830239772796631 Domain: biomedical Document type: Study Language: en The aspects of both tools can be scored as either adequately/high specified = Two points, moderate specified = One point, poorly/not specified = Zero points. To provide a quantitative measure of the overall risk of bias in each study, the following equation (Equation (1) ) was used for both QUIN and ROBFEAD tools . (1) Final score = Total score × 100 2 × number of criteria applicable Section title: Quality assessment Educational score: 2.130249261856079 Domain: biomedical Document type: Study Language: en Two authors (A.-K. B. and I. S.) followed clear guidelines for each criteria ensuring consistency and transparency and conducted the assessments independently. Any uncertainties about missing data or disagreements were then resolved by discussion with a third author (J.-O. S.). Section title: Study selection Educational score: 4.023169040679932 Domain: biomedical Document type: Study Language: en With the described literature search strategy, 1787 studies were retrieved . Following eliminating duplicates, 1055 studies underwent the abstract and title screening and 382 studies were deemed eligible for a thorough analysis. Following the full-text analysis, 77 studies were extracted that met the inclusion criteria [ 1 , 12 , 18 , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ]. Despite our extensive efforts, 23 reports were not retrieved. While we cannot definitively assure whether these studies used homogeneous or heterogeneous material models, we note that the inability to review them does pose a risk of missing some material models relevant to our study. Unfortunately, we have no control over this matter. Fig. 1 The systematic review flowchart of the study selection process (PRISMA flowchart ). n stands for the number of publications and CT for computed tomography. Fig. 1 Section title: Study selection Educational score: 2.4465112686157227 Domain: biomedical Document type: Study Language: en Multiple studies were carried out by identical research groups, with a total of 55 authors and 31 research groups performing FE analysis using heterogeneous material models for the mandible bone. These studies were conducted from 2005 to 2024, uncovering trends in research interests over time. There are three papers published before 2010, 31 between 2010 and 2019, and 43 since 2020. Section title: Study selection Educational score: 4.042579174041748 Domain: biomedical Document type: Review Language: en The reviewed papers cover a wide spectrum of FE analysis within the craniomaxillofacial research field. Topics include bone-implant interaction (17 studies) , fracture fixation (13 studies [ 12 , 29 , 31 , 48 , 49 , , , , , , , 86 , 95 ]), mandible reconstruction (10 studies [ 32 , 38 , 41 , , , , , , 93 , 97 ]), osteotomy techniques (eight studies ), implant-retained overdentures (six studies ) and motion/temporomandibular joint dynamics (seven studies ). Less frequent topics, represented by less than five publications each including dental bridges (four studies ), general investigations on healthy mandibles (three studies ), condylar prosthesis (three studies ), periodontal ligament (two studies ), influence of CT imaging on FE studies (two studies ), tumor pathology (one study ), and third molar tooth orientation analysis (one study ). Among the 77 papers, 54 studies used the full geometry of the mandible bone for FE analysis, while 23 studies employed just a block of mandible bone in the region of interest of their studies. Section title: Study selection Educational score: 3.9657905101776123 Domain: biomedical Document type: Review Language: en The process of attributing specific material properties to individual elements or nodes within a FE model based on information obtained from medical images and established material models is called “material assignment”. This procedure is referred to by various names across different studies, such as material mapping based on Hounsfield Units, and heterogeneous or inhomogeneous material modeling . This can be done by various approaches including voxel-based , element-based or node-based methods . There are several commercial software packages and in-house developed toolboxes available to perform the material assignment. Among the 77 reviewed studies, 20 used Mimics software package (Materialise NV, Leuven Belgium), one used mechanical finder (Research Center for Computational Mechanics, Tokyo, Japan), four used in-house developed Abaqus subroutines, and the remaining 52 studies did not clearly mention which toolboxes they used for material assignment to the mandible bone. Section title: Heterogeneous material models for mandible Educational score: 4.193320274353027 Domain: biomedical Document type: Study Language: en While reviewing the 77 FE studies and their employed density-modulus relationships, 12 different material models for the relationships between apparent ( ρ app ) or ash density ( ρ ash ) and Young's modulus ( E ) were identified and listed in Table 1 [ 10 , 15 , , , , , , , , ]. The Mimics empirical default formula (first cited by Xin et al. ) is the most frequently cited density-modulus relationship (Equation (2) ), considering solely the number of citations (18 times). However, when counting research groups using heterogenous material models, the Mimics formula is quoted only by three out of 24 research groups. Both material models proposed by Keyak et al. (Equation (3) ) and Rho et al. (Equation (4) ) emerge as the most used density-modulus relationships with each cited by six out of 31 research groups. (2) E [ GPa ] = − 0.3888 + 5.925 ρ a p p [ g / cm 3 ] E [ GPa ] = 33.9 ρ a s h 2.2 [ g / cm 3 ] , ρ a s h ≤ 0.27 (3) E [ GPa ] = 5.307 ρ a s h [ g / cm 3 ] + 0.469 , 0.27 < ρ a s h < 0.6 E [ GPa ] = 10.2 ρ a s h 2.01 [ g / cm 3 ] , ρ a s h ≥ 0.6 (4) E [ GPa ] = 0.51 ρ a p p 1.37 [ g / cm 3 ] Table 1 12 heterogeneous material models used in the reviewed finite element studies for the mandible. Table 1 Section title: Heterogeneous material models for mandible Educational score: 4.028175354003906 Domain: biomedical Document type: Review Language: en Despite conducting an extensive literature review, the original sources for the Mimics empirical default formula could not be identified. Nevertheless, this density-modulus relationship has gained widespread recognition and become well-established since 2013 . The remaining 11 material models originate from 10 studies with two employed density-modulus relationships proposed by an individual study from Rho et al. . In five studies, the material model was proposed based on in vitro experiments, investigated with bone samples, typically through uniaxial compression or tension tests . Two studies used a complete femur for their experiments and adapted previously proposed density-modulus relationships . However, most recent studies employed a mathematical approach, where the material models were derived based on theoretical values for density and elastic modulus or involved cone beam computed tomography-based estimations . Section title: Heterogeneous material models for mandible Educational score: 3.7089951038360596 Domain: biomedical Document type: Study Language: en Taking into account the mathematical characteristics behind the material models, these 12 density-modulus relationships presented in Table 1 include 18 sub-functions. Among these, there are 11 power functions with exponents ranging from 1.16 to 7.4 [ 10 , 15 , , , , , , 116 , 117 ] and one sigmoid function . Additionally, six linear relationships were determined , one of which serves as an interpolation between two power functions . Section title: Heterogeneous material models for mandible Educational score: 3.1788856983184814 Domain: biomedical Document type: Study Language: en The origin of the density-modulus relationship varies among different bones. Two utilize data from the femur , one from the tibia , one from the pelvis , one employs a pool of various bone sites , and one model is derived from the femoral and tibial diaphysis of the steer . Among these, five density-modulus relationships were specifically proposed based on data for the human mandible bone [ 10 , 15 , , , ]. Section title: Heterogeneous material models for mandible Educational score: 2.531827926635742 Domain: biomedical Document type: Study Language: en The original studies are conducted based on different bone domains. Among the material models, three were derived exclusively for trabecular bone , one for cortical bone , and the rest considered both bone domains, with two studies offering different sub-functions according to the density range . Section title: Heterogeneous material models for mandible Educational score: 3.930530309677124 Domain: biomedical Document type: Study Language: en Considering the constitutive modeling of the bone tissue, three material models were initially developed to accommodate the orthotropic nature of bone, addressing the directional variations by separated sub-functions . Rho et al. proposed the two density-modulus relationships as orthotropic material models for the trabecular tibia bone and cortical mandible bone. Also, O'Mahony et al. proposed an orthotropic material model consisting of three directional sub-functions. Section title: Heterogeneous material models for mandible Educational score: 4.146717548370361 Domain: biomedical Document type: Study Language: en The differences between the material models proposed by original studies were also compared qualitatively in Fig. 2 A and 2B. Prior to this comparison the material models defined in ash density ( ρ ash ) by Cong et al. and Keyak et al. for femur bone were converted to apparent density ( ρ app ) using the correlation ρ ash = 0.6 ρ app . According to Schileo et al. , this correlation is valid for the whole density range of the femur bone. In Fig. 2 A each curve presents the proposed density-modulus relationships which allows a comprehensive understanding of how different material models relate to one another. Fig. 2 B shows numerical calculations of Young's modulus for two representative apparent density values. Fig. 2 Comparison of density-modulus relationships used by finite element studies for material modelling of the human mandible bone. A: The heterogeneous material models are presented on a logarithmic scale, with the corresponding bone domain and type. Two vertical lines in light grey indicate the representative apparent density values in relation to bone domains used for the calculations in Fig. 2 B B: Numerical calculation of Young's modulus for two representative apparent density values of 1.3 g/cm³ for trabecular (blue bars), and 1.6 g/cm³ for cortical (orange bars) bones . In both subfigures A and B, dashed horizontal lines represent the most frequently used homogeneous Young's modulus for trabecular (1.37 GPa) and cortical (13.7 GPa) bone . Fig. 2 Section title: Risk of bias Educational score: 4.09584379196167 Domain: biomedical Document type: Study Language: en Table 2 summarizes the quality assessment results of the risk of bias with the QUIN and ROBFEAD tools for each original study. Studies were characterized by a low to medium risk of bias. The highest risk in the in vitro studies was found in Carter and Hayes , Dalstra et al. , and O'Mahony et al. each with 54 % score, and the highest risk among the FE studies was found in Ramos et al. with 57 % score. The density-modulus relationship known as Mimics empirical equation is characterized by an unknown/high risk of bias as the origin and methodology remained unclear. Table 2 Quality assessment of original studies. A: Quality Assessment Tool for In vitro Studies , B : risk of bias tool for the use of finite element analysis in dentistry (ROBFEAD). Table 2 Section title: Discussion Educational score: 4.130947113037109 Domain: biomedical Document type: Study Language: en To achieve precise results in FE analysis, in addition to various other considerations, e.g. loading scenarios, boundary conditions, and the geometric details of the bone, ensuring the accurate integration of material properties stands out as a critical factor . Bone is inherently a heterogeneous structure, composed of various materials arranged in complex patterns. Using heterogeneous material models in FE analysis allows for a more accurate representation of the actual mechanical behavior of bones compared to assuming homogeneity and enables more realistic calculations of localized stress and strain distributions . The consideration of heterogeneous material models in comparison to homogeneous models facilitates the FE models to have a greater energy dissipation and a more realistic prediction of the apparent stiffness and transition between the bone domains, which avoids numerical singularities at the interface of cortical and trabecular domains . Furthermore, integrating CT-based bone properties into FE analysis enables subject-specific modeling, allowing the comparison of individuals with different pathologies in biomechanical analysis and clinical applications. Section title: Systematic review Educational score: 3.8249189853668213 Domain: biomedical Document type: Review Language: en The increasing interest in the topic of density-modulus relationships within biomedical research on the mandible is evident from the notable concentrations of publications in recent years. However, given the challenge posed by the multitude of existing material models from the literature and the increasing complexity of heterogeneous material modeling, which requires more effort, knowledge, and computational resources, yet a tendency to use homogeneous material models prevails . This persists despite the multiple benefits associated with heterogeneous material modeling, as previously discussed. Section title: Systematic review Educational score: 4.060656547546387 Domain: biomedical Document type: Review Language: en The review revealed a lack of consensus among these studies regarding heterogeneous material modeling and assigning methods. Also, some studies were found which used the material model outside their intended density ranges or applied the density-modulus relationship uniformly in all directions (isotropic) despite them being primarily proposed for orthotropic materials. Such assumptions, which are common in FE analysis, may impact the accuracy of the modeling and should therefore be examined through sensitivity analysis . Careful attention must be given to the correct unit conversion of the parameters of the density-modulus relationship e.g., density and elastic modulus, as this may have a significant influence on the results. Section title: Systematic review Educational score: 3.884392023086548 Domain: biomedical Document type: Study Language: en Additionally, it was observed that after selecting the appropriate heterogeneous material model, researchers used various software toolboxes for the material assignment process. Next to the toolboxes employed by the 77 reviewed studies (Mimics software package and mechanical finder) there are additional toolboxes such as Bonemat , Bonemapy , Py_bonemat_abaqus , Simpleware ScanIP (Synopsys Inc., United Kingdom) , CTPixelMapper , and in-house developed python plugins . Based on authors experience, using a unique material model with various toolboxes, each developed using distinct assignment methods, results in considerably different Young's modulus distributions . Notably, 52 out of the 77 studies did not specify which toolboxes or assignment strategy (node-wise or element-wise) they used, making it difficult to compare their findings. Section title: Heterogeneous material models for mandible Educational score: 3.9732468128204346 Domain: biomedical Document type: Review Language: en In order to provide a better insight into the origin and reliability of density-modulus relationships and to sort the existing approaches, the second goal was to conduct an extended search identifying original studies that initially introduced heterogeneous material models. In this context, Helgason et al. and Knowles et al. published review studies of heterogeneous material models for human bones and discussed influences on the Young's modulus and outcomes of FE modeling . Through the present review, 12 material models from 10 original studies were identified in total. Section title: Heterogeneous material models for mandible Educational score: 3.9879374504089355 Domain: biomedical Document type: Study Language: en The absence of a consensus on the material model and the considerable large deviation among them may yield to serious implications for modeling accuracy . Several factors were identified as sources of this deviation: 1) difference in study type including in vitro experiments, mathematical-based approach or combined simulation-experimental-based approach, 2) differences in experimental mechanical test types e.g., tension or compression test or test setups, such as constrained or uniaxial loading, and sampling rates, 3) differences in the methodology of the numerical approaches, such as different boundary condition or use case, 4) different bone samples or donors in terms of anatomical sites, geometries (cubes/cylinders or full bone), dimensions, bone domains (cortical or trabecular), the quantity of samples, sex, and even specimen-specific differences. Section title: Heterogeneous material models for mandible Educational score: 3.9180707931518555 Domain: biomedical Document type: Study Language: en Irrespective of the study approaches, there is significant variation in the anatomical sites of the specimens studied in the original research. Studies by Ciarelli et al. and Morgan et al. revealed considerable variability in the density-modulus relationship depending on the anatomical site [ 22 , , , , , ]. This becomes apparent, for instance, in samples of vertebral bones, which result in a weaker relationship between elasticity and density than the values derived from long bone samples . Section title: Heterogeneous material models for mandible Educational score: 3.9734597206115723 Domain: biomedical Document type: Study Language: en The quantity and characteristics of bone samples differ in original studies. Despite Cong et al. claiming that complete bones are more clinically relevant, most in vitro studies use cubic or cylindrical bone samples. Those are generally employed in a sizable cohort of samples, but it is notable that these samples often originate from a limited number of donors. For instance, Dalstra et al. tested 57 samples taken from only two donor pelvic bones. This methodology restricts the ability to explore population-based differences in bone characteristics. Additionally, the potential influence of sex, age and ethnic factors on bone properties raises questions, especially when the ethnicity of the bone samples is not specified or if studies do not select a cohort of equal size in terms of their sex . Section title: Heterogeneous material models for mandible Educational score: 4.064522743225098 Domain: biomedical Document type: Study Language: en Since the trabecular and cortical bone domains cover a wide range of density, dividing the material model into sub-functions based on density ranges, known for both bone domains, is an option to better estimate the Young's modulus. Therefore, Pinheiro et al. created separated sub-functions for the cortical and trabecular domains. However, this approach poses a challenge of discontinuity in material properties at the interface of bone domains, leading to complications in mesh convergence in FE analysis. An alternative strategy is provided by Keyak et al. , who addressed this issue by considering the transitional domain between cortical and trabecular bone within a linear sub-function, which ensures continuity at the boundaries . Section title: Heterogeneous material models for mandible Educational score: 4.110097408294678 Domain: biomedical Document type: Study Language: en Additionally, several FE studies were identified that employed a density-modulus relationship proposed as orthotropic sub-functions for an isotropic behavior of the bone. For instance, all 15 FE studies that used the orthotropic material model from O'Mahony et al. applied the superior-inferior sub-function as an isotropic material model for all directions. Bone anisotropy is crucial for accurately estimating the elastic modulus since the relationship between mineral content and modulus varies with the direction of loading [ , , ]. Section title: Heterogeneous material models for mandible Educational score: 3.0291359424591064 Domain: biomedical Document type: Study Language: en According to the quality assessment analysis, all assessed studies have a low to moderate risk of bias ( Table 2 ). Nevertheless, the density-modulus relationship proposed by Mimics software lacks transparency regarding its development and reliability and should therefore be used with caution. Section title: Recommendations, limitations and future work Educational score: 4.0975446701049805 Domain: biomedical Document type: Review Language: en Considering the focus of this review, several recommendations can be made for using heterogeneous material models for subject-specific FE models. – When using a material model based on in vitro experiments, special attention should be paid to the type of experiments and the variation in samples. In the studies in which the proposed material model is generated based on mathematical calculations, caution is required due to the potential issues with missing validation and mesh convergence, which can compromise the accuracy of the FE analysis. – The range of applicability of the proposed density-modulus relationship in terms of bone domain and directional behavior should be respected and researchers are advised to check in advance if the density-modulus relationship they intend to use is valid only for specific bone domains, density ranges or direction . For instance, the material model from Dalstra et al. is proposed only for the trabecular bone, covering the range of 0.109–0.959 g/cm 3 , and should not be used to model the bone out of this range. – We also recommend that researchers carefully consider the material assignment method of the toolbox they employ and explicitly report it in their studies. This will enhance the reliability, comparability and reproducibility of the results for future researchers. – Furthermore, if original studies have proposed several density-modulus relationships, for example for different anatomical sites proposed by Rho et al. , the specific employed material model from the original study should be cited in the scientific papers. Section title: Recommendations, limitations and future work Educational score: 3.882768392562866 Domain: biomedical Document type: Study Language: en Although best effort was made to comprehensively gather available information, this study has some limitations. Initially designed to focus on reviewing FE analysis of the mandible using density-modulus relationships to model bone mechanical properties, it did not specifically target the material models themselves. Consequently, we may have missed some material models developed for mandible bone that have not yet been identified or cited. However, we attempted to overcome this issue through a randomized hand search. Additionally, 23 reports could not be accessed, and the inability to review them represents a potential risk of overlooking important material models that are relevant to our systematic review. Section title: Recommendations, limitations and future work Educational score: 4.084763050079346 Domain: biomedical Document type: Study Language: en Further experiments and validations have to be conducted to: (1) provide recommendations on existing heterogeneous material models, (2) analyze the characteristics of the density-modulus relationships such as the sex-dependency, (3) investigate the influence of the employed heterogeneous material model through a comparative FE study on field variables such as stress and strain and (4) propose new models exclusively designed for both domains of the mandible bone. Prior to this, a systematic review is necessary to design a standard experimental protocol. It is also advised to use a validation approach by combining simulation and experiments such as the method presented by Cong et al. to validate the material model. They estimated both power and sigmoid functions parameters, which are commonly used for bone material models, by means of optimization techniques. They iteratively updated the parameters of these functions, aiming to align the predicted femur stiffness derived from FE analysis with the experimentally determined bone stiffness acquired by them through mechanical testing . Section title: Recommendations, limitations and future work Educational score: 4.048045635223389 Domain: biomedical Document type: Review Language: en Future research needs to go beyond isotropic heterogeneous material models and explore orthotropic heterogeneous material models in detail . This approach provides a more accurate representation of the anisotropic nature of bone tissue, improving the precision of stress and strain predictions, and leading to better-informed clinical decision-making and more effective treatment planning. Furthermore, orthotropic material modeling offers the potential for even more precise subject-specific analysis by accounting for the directional dependencies of bone mechanical properties. Of the 77 reviewed scientific papers, 75 FE studies applied isotropic heterogeneous material models. While these models are more realistic than isotropic homogeneous ones, they still fail to capture the anisotropic nature of bone. Furthermore, a systematic study is required to investigate the influence of the material assignment methods and toolboxes on the results and stress distribution within the bone as inter-method differences were observed in the results produced by various material assignment toolboxes. Section title: Conclusion Educational score: 4.1545281410217285 Domain: biomedical Document type: Review Language: en This systematic review aims to assist researchers in the craniomaxillofacial field in selecting more accurate heterogeneous material models for building subject-specific FE models of the mandible. This was achieved by conducting a systematic review on density-modulus relationships used for material modeling of the mandible bone, providing an overview of the material models that have been used and discussing the origin of the models and their quality. The lack of consensus on the optimal material model for estimating Young's modulus from mineral density for the mandible bone remains a significant challenge. The presented review highlights the variability in relationships in terms of bone domain, the methodology based on which the relationships are created, different experimental setups, isotropy or anisotropy structure, and anatomical site. This reveals the importance for researchers to carefully consider the characteristics of a relationship in accordance to the objective of their study before employing it. Future research should focus on developing new heterogeneous material models that more accurately and exclusively reflect the biomechanical properties of the mandible bone and its anisotropic structure based on a standardized experimental protocol and validating the models through methods combining simulation and experiment. Additionally, a comparative FE analysis is needed to investigate the significance of the available material models and different material assignment approaches on the resulting field variables of the bone. By addressing these challenges, researchers can improve the accuracy of subject-specific FE analysis, leading to better clinical decision-making and treatment outcomes in the craniomaxillofacial field. Section title: Funding Educational score: 1.0124231576919556 Domain: other Document type: Other Language: en The authors are grateful to the 10.13039/501100016070 ITI foundation (the International Team for Implantology) for financial support . Section title: CRediT authorship contribution statement Educational score: 0.9774824976921082 Domain: other Document type: Other Language: en Iman Soodmand: Writing – review & editing, Writing – original draft, Visualization, Validation, Resources, Project administration, Methodology, Investigation, Funding acquisition, Formal analysis, Data curation, Conceptualization. Ann-Kristin Becker: Writing – review & editing, Writing – original draft, Visualization, Validation, Resources, Project administration, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Jan-Oliver Sass: Writing – review & editing, Writing – original draft, Resources, Methodology, Investigation, Funding acquisition, Formal analysis, Conceptualization. Christopher Jabs: Writing – review & editing, Validation, Resources, Data curation. Maeruan Kebbach: Writing – review & editing, Supervision, Project administration, Funding acquisition. Gesa Wanke: Writing – review & editing, Resources, Methodology, Conceptualization. Michael Dau: Writing – review & editing, Supervision, Funding acquisition. Rainer Bader: Writing – review & editing, Supervision, Project administration, Funding acquisition, Conceptualization. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Study | biomedical | en | 0.999996 |
PMC11698924 | Section title: Introduction Educational score: 4.041601657867432 Domain: biomedical Document type: Other Language: en At the core of living tissue, the cell serves as a functional unit , coordinating a vast range of biochemical processes essential to life. This entity harbours a dynamic world of subcellular structures and molecular mechanisms, within which energy metabolism operates. It defines the set of pathways, known as metabolic pathways, corresponding to a complex network of enzymatic reactions necessary for the renewal of the cellular needed energy, continuously changing according to the demand , . Section title: Introduction Educational score: 4.2812089920043945 Domain: biomedical Document type: Study Language: en Within these metabolic pathways, glucose degradation initiates within the cytoplasm, leading to the synthesis of adenosine triphosphate (ATP) and pyruvate, subsequently diverging into lactate or acetyl-CoA depending on cellular demand. Acetyl-CoA, which is also produced from fatty acids via the β -oxidation pathway and from the breakdown of amino acids, plays a crucial role in the tricarboxylic acid cycle, facilitating energy production in the mitochondria. Section title: Introduction Educational score: 3.8395111560821533 Domain: biomedical Document type: Study Language: en Among the possible known factors impacting energy metabolism, physical exercise causes major changes , , requiring the body to adapt to supply the energy needed for muscular contraction. Depending on the intensity, duration, and type of exercise, the amount and rate of energy consumption changes. This leads to the activation of complementary pathways, and the tune control of the enzymatic activities through cross-reaction between the different metabolites of the cells as well as of the organs. Section title: Introduction Educational score: 4.061964988708496 Domain: biomedical Document type: Study Language: en In this context, fatty acids, through the β -oxidation, represent the most efficient cellular energy source but are constrained by production rates. Increased energy demand leads cells to resort to alternative sources, such as more powerful sources like glucose. Interestingly, because all of the energy pathways are interconnected and finely regulated by common co-activators and co-inhibitors, the overuse of glycolysis and carbohydrate oxidation in case of high energy demands, will limit the use of fatty acids. Energy metabolism is, therefore, a complex system and it is difficult to predict its behaviour simply by knowing its elementary components. It is therefore necessary to model it to facilitate its understanding and study . Section title: Introduction Educational score: 4.199883460998535 Domain: biomedical Document type: Review Language: en Health condition is also a major factor influencing changes in energy metabolism, notably by affecting the way the body produces, stores, and uses energy. Multiple chronic and inherited diseases, such as cancer, diabetes, and cardiovascular diseases, lead to metabolic alterations, particularly in the mitochondria, which can participate in the disease progression by limiting cell functioning and/or favouring inflammation and pathogenic functions. Among these diseases, neuromuscular diseases represent a critical clinical challenge by their multiplicities in terms of origin and symptoms. While metabolic defaults can be a direct consequence of disease, certain neuromuscular disorders, such as calpainopathy, present metabolic defaults as a secondary effect, making it even more challenging to understand and possibly anticipate. Given the involvement of various enzymes, traditional experimental approaches would face limitations as it would be complicated to test each enzyme. Therefore, the need to develop new tools aimed at modelling the energy metabolism and its adaptation to different contexts of demand is of paramount importance and could be used as a lever for the development of new therapeutic approaches. Section title: Introduction Educational score: 4.96291446685791 Domain: biomedical Document type: Study Language: en Calpainopathy , also known as Limb Girdle Muscular Dystrophy type 2A (LGMDR1), is an autosomal recessive genetic disorder affecting the proximal muscles of the shoulder and pelvic girdles. It is characterised by muscular atrophy leading to a progressive loss of mobility in affected patients. Unlike other dystrophies, calpainopathy is caused by mutations in the CAPN3 gene, which codes for a calcium-dependent protease, calpain-3, involved in calcium homeostasis, and in the remodelling of sarcomeres, the multiprotein structures responsible for contraction. In the case of muscle damage, persistent calcium influx activates calpain-3, enabling the muscles to repair and adapt. Mutation of the CAPN3 gene induces a loss of expression of the protein, leading to a disorganisation of sarcomeres, a deregulation of calcium flux and, as a secondary consequence, oxidative stress and energy metabolic alterations. Among these alterations, the loss of calpain-3 leads to the dysfunction of mitochondria, the alteration of β -oxidation, and a loss of equilibrium between the different energy pathways ultimately leading to a decline in ATP production rate , . While the exact mechanisms by which this occurs are not yet fully understood, the understanding of its exact disturbance among the disease heterogeneity is of definite interest at preclinical and clinical levels. Section title: Introduction Educational score: 3.5461461544036865 Domain: biomedical Document type: Review Language: en To this date, there is no cure for this disease, and clinical care strategies remain based on symptom and pain relief. With the idea of studying the potential of physical exercise as a complementary approach to improve the clinical care of patients with this disease, previous research made the hypothesis that an exercise protocol, tailored to each patient's metabolic state, could lead to improvements in motor function and be considered as a clinical care strategy , . Section title: Introduction Educational score: 4.167015552520752 Domain: biomedical Document type: Study Language: en Modelling in biology is usually used to decipher biological processes, to reproduce experimental results or, conversely, to predict experimentally unstudied events. In the case of metabolism studies, we can predict which pathway will be favoured by given conditions (initial conditions of metabolites, pathways voluntarily blocked) or, on the contrary, which pathways will be altered by changes in enzymatic activity. The main powerful methods for analysing and predicting the properties of genome-scale metabolic models are Flux Balance Analysis (FBA) and related approaches , , . The fundamental assumptions underlying the FBA framework for computing solutions are the steady state condition and the principle of optimality. The goal of FBA is to identify a flux distribution that achieves the maximisation of an objective function, such as the rate of biomass production or energy production. Section title: Introduction Educational score: 4.00911808013916 Domain: biomedical Document type: Study Language: en An approach to enhance the quantitative accuracy of FBA predictions involves imposing constraints on uptake fluxes. In absence of measurements of these fluxes, FBA computations depend on setting bounds for exchange reactions to simulate specific cellular environments. Various techniques have been employed to approximate uptake fluxes, leveraging intricate details of regulatory networks , transporter saturation kinetics , transcriptomic data , and training datasets for machine learning-based methodologies . Section title: Introduction Educational score: 4.159976005554199 Domain: biomedical Document type: Study Language: en We chose to use MitoCore , a constraint-based metabolic model specifically designed to capture mitochondrial processes. Constraint-based models such as MitoCore work by imposing physiological constraints to simulate steady-state metabolic fluxes. This approach enables us to anticipate key aspects of energy metabolism in healthy and pathological conditions, and to understand how cells balance pathways such as oxidative phosphorylation and glycolysis. MitoCore's focus on mitochondrial pathways makes it particularly useful for understanding energy dysregulation, specifically in diseases such as calpainopathy where mitochondrial dysfunction plays a central role. In addition, the model captures reversible reactions, such as those catalysed by enzymes like lactate dehydrogenase, enabling us to examine changes in metabolic fluxes under variable cellular conditions. Section title: Introduction Educational score: 3.9018332958221436 Domain: biomedical Document type: Study Language: en While not dynamic in the traditional sense, constraint-based modelling allows for a snapshot of the metabolic state under specific conditions such as those defined by energy demand, substrate availability, and environmental factors (nutrient intake) and the addition of constraints allows us to mimic energy production for multiple energy demands and its defects with altered metabolic pathways instead of blocked ones. Section title: Introduction Educational score: 4.2238545417785645 Domain: biomedical Document type: Study Language: en It is in this context, at the interface between physiology, pathophysiology and metabolic modelling, that this study takes place. Using Flux Balance Analysis (FBA) , we have constructed a healthy constraint-based model of the energy metabolism of a murine muscle cell that we can adapt to different pathological or individual situations, providing an instantaneous view of metabolic fluxes. First, we simulated on this model the multiple energy demands of physical exercise, expressed at 4 different intensities of maximum oxygen consumption, called V O 2 m a x . These intensities correspond to the extremes of energy demand from rest (25%) to 100% of V O 2 m a x , and including the intensities of the transitions between pathways: 65%, corresponding exclusively to the use of the aerobic pathway, and 85% corresponding to a combination of the aerobic and anaerobic pathways. This allowed us to ensure that the healthy model had a proper adaptation in the balance between the main energy pathways. Secondly, as a case study, we constrained this model with the known metabolic disorder in the most common limb-girdle dystrophy, calpainopathy. By applying predetermined values of key fluxes, we can compare the healthy to the calpainopathy-like model and highlight potential compensatory pathways and key regulators of the altered metabolism. The method developed in this study is intended to be adapted to other diseases with dysregulation of energy metabolism and should open up new potential therapeutic approaches. Section title: Healthy muscle cell's metabolic model under different energetic demands Educational score: 4.115266799926758 Domain: biomedical Document type: Study Language: en In order to model muscle energy metabolism and to adapt it to different contractual conditions while allowing to anticipate compensatory mechanisms and/or potent modulators, we decided to adapt the well described MitoCore model , a mitochondrial metabolic model containing 485 reactions, including 155 mitochondrial reactions, 168 cytosolic reactions and 162 transport reactions of a human cardiac cell, to a healthy murine muscle cell used as control. To do this, we automatically checked for the presence of murine enzymes using the Brenda and Unitprot databases, suppressing only one enzyme for which no clear information supporting its existence in murine were found (see Method for more details). Section title: Healthy muscle cell's metabolic model under different energetic demands Educational score: 4.140867233276367 Domain: biomedical Document type: Study Language: en Since the model relies on FBA with an objective function focused on biomass production, the fluxes of nutrient uptakes have to be settled. The original model has been defined with human cardiac glucose, fatty acids and amino acids fluxes entry, which do not correspond to murine skeletal muscle cell. Since these fluxes of nutrient uptakes, notably the glucose and fatty acids, are not well quantified for the murine skeletal muscle cell, we attempted to predict them using a proper FBA combined with Flux Variability Analysis (FVA) approach, which optimises energy production with respect to the proportions of muscle energy pathways known from the literature (see Method for more details), using experimental data of ATP production associated to oxygen consumption as constraints. Section title: Healthy muscle cell's metabolic model under different energetic demands Educational score: 4.175198554992676 Domain: biomedical Document type: Study Language: en Under resting conditions (25% of maximal oxygen consumption) we obtained ranges of glucose and fatty acid fluxes allowing us to determine the exact value for each nutrient flux matching the expected proportion of 40% of carbohydrate oxidation (CHO) and 60% of β -oxidation. We then performed the same calculation but at different levels of exercise intensity with increasing ATP production rate, dioxygen consumption rate and different proportions of energy pathways . At 65, 85 and 100% of maximum oxygen consumption, FVA provides ranges of fluxes for each nutrient allowing us to determine these optimal values for both glucose and fatty acids ( Table 1 ). Table 1 Fixed constraint from experimental data of O 2 inputs and ATP outputs fluxes set to compute the input values of glucose and fatty acids in the control model, and expressed in μmol.gDW −1 . min −1 . Each set of O 2 and ATP is used to simulate 4 conditions of energy demands, expressed as 4 percentages of maximum oxygen consumption: 25, 65, 85 and 100% of VO 2 max . Glucose and fatty acids uptake fluxes were computed through a FVA method, allowing to respect constraints of energy demand, associated to carbohydrate oxidation (CHO) and β -oxidation proportions physiologically consistent . Table 1 Intensity of exercise (% of V O 2 m a x ) 25% 65% 85% 100% Fluxes fixed O 2 -3.7 -7.9 -11.1 -14 ATP 14.6 36.52 54.8 75 Fluxes computed by FBA Glucose -0.03 -0.13 -0.6 -2 Fatty acids -0.1 -0.27 -0.3 -0.08 Section title: Healthy muscle cell's metabolic model under different energetic demands Educational score: 4.154463291168213 Domain: biomedical Document type: Study Language: en This approach allowed us to determine that the needed fluxes of glucose in a single cell increase continuously from 25% to 100% of V O 2 m a x ( Table 1 ) reaching a fold of 66. However, concerning the fatty acids entry in a cell, we noted an increase by 3 fold from 25% to 85% of V O 2 m a x then followed by a limitation of fatty acids entry due to excess of glucose consumption. Once the constraints on O2 consumption, ATP production, glucose and fatty acids had been applied, the fluxes obtained in the FBA solution had to be checked to validate the behaviour of our model. For this purpose, we selected key enzymatic reactions from the main energy pathways involved in the ATP production to evaluate the biological consistency of our model and the change in their balance with the intensity of energy demand . Figure 1 Fluxes expressed in absolute value (A) and proportions (B) of selected key enzymatic reactions from the main metabolic pathways used for ATP production, for each energy demand of physical exercise in a control muscle cell model. The reactions chosen as representative are phosphoglycerate mutase for glycolysis, acetyl-CoA acyltransferase for β -oxidation, 3-hydroxybutyrate dehydrogenase for ketone body degradation and leucine and isoleucine transaminase. The computed proportion of the main metabolic pathways are physiologically consistent, validating the behaviour of the control model. Figure 1 Section title: Healthy muscle cell's metabolic model under different energetic demands Educational score: 4.128113746643066 Domain: biomedical Document type: Study Language: en For each exercise intensity simulation, the instant fluxes and proportions of the ATP producing pathways changed as expected. We observed an increase by 57 fold in glycolysis flux from 25% to 100% of V O 2 m a x . If the Isoleucine, Leucine and ketone bodies degradation was noticeable at 65% and 85%, their contribution to the total ATP produced dropped with the increase in intensity, whereas the fatty acids increased from 25% to 85% of V O 2 m a x and then totally dropped at 100% . Looking at the proportion of metabolic pathways used to produce ATP, the results are consistent with the literature , and confirm that there is around 60% of fatty acids degradation (Fatty Acid metabolism) at rest, 50% at medium exercise intensity, 20% at high exercise intensity and around 2% at maximal intensity. Section title: Healthy muscle cell's metabolic model under different energetic demands Educational score: 3.1385750770568848 Domain: biomedical Document type: Study Language: en Thus, we have built and validated a control murine model of single-cell energy metabolism under multiple constraints of demands, which we can now adapt to any pathological condition. Section title: Calpainopathy-like muscle cell's metabolic model under different energetic demands Educational score: 4.314884662628174 Domain: biomedical Document type: Study Language: en To simulate the disease in the metabolic network model, we then gathered all reported mitochondrial consequences and metabolic dysfunctions associated with calpainopathy described in the literature from murine models , . It is important to note that, to date the experimental data available are limited and only two studies provide quantitative or semi-quantitative evaluations of muscular metabolic alterations in calpainopathy. Most of these disease-induced regulations come from the analysis of differential gene expressions (RNAseq data) and few come from direct measurements of enzymatic activity. Regarding the studies reporting gene expression changes, the match between the list of enzymes in our control model with the RNAseq results gives us 18 altered enzymes of interest in the murine calpainopathy model (see Supplementary Table S4). These enzymes are mainly related to β -oxidation, the Krebs cycle, the mitochondrial respiratory chain, and amino acid degradation. Since it's known that a given amount of enzyme can give rise to different levels of activity depending on the cellular context and co-factors, we assumed that only the maximal enzymatic activity is proportional to the total gene expression. Concerning the data obtained from direct enzymatic activity measurements in the muscle of the calpainopathy murine model, only two enzymes from glycolysis matched with the enzyme included in our control model . The activity of aldolase was reported to increase by 133%, while the activity of lactate dehydrogenase increased by 287% when compared to non-mutated animals. Because the reported enzymatic activities were measured under controlled conditions in vitro , we also assumed that these activities referred to their maximum. Thus, to build the calpainopathy-like model, we weighted the maximum fluxes calculated by FBA under all conditions of intensity from the control model for each selected enzyme, with their corresponding correction factor. The resulting fluxes are then used as an upper bound for the model, allowing variations in enzyme activity but limiting their maximum. Section title: Calpainopathy-like muscle cell's metabolic model under different energetic demands Educational score: 4.094756126403809 Domain: biomedical Document type: Study Language: en Our developed calpainopathy-like model, with disease-specific constraints, was then run with FBA calculation using the same nutrient entry fluxes than those calculated for the control model. Finally, we compared the capacity of the calpainopathy-like model to produce ATP at each intensity of V O 2 m a x and the balance between energy pathways with the control model . Figure 2 Comparison of the ATP production fluxes (A) and the proportions (B) of its main contributing pathways, for each intensity of energy demand, in control and calpainopathy-like models. The reactions chosen as representative are phosphoglycerate mutase for glycolysis, acetyl-CoA acyltransferase for β -oxidation, 3-hydroxybutyrate dehydrogenase for ketone bodies degradation, leucine and isoleucine transaminase and glutamate dehydrogenase. Figure 2 Section title: Calpainopathy-like muscle cell's metabolic model under different energetic demands Educational score: 4.348963737487793 Domain: biomedical Document type: Study Language: en In both models, the total flux of ATP production increased with intensity level, but less so in the calpainopathy-like model . Although the disease-like model was able to produce the necessary ATP at 25% of V O 2 m a x , as effort increases, the model became more and more deficient in terms of ATP production, dividing the required ATP by 1.8 at 100% of V O 2 m a x . Associated with these intensity-induced decreases in ATP production, we noted an imbalance between the energy pathways when compared to the control model overall to the detriment of β -oxidation (FA metabolism). If at 25% of V O 2 m a x , we failed to observe any change in the proportion between the main energy pathways, we noted a marked decrease in β -oxidation compensated by an increase in ketone bodies and amino acid degradation at 65% of V O 2 m a x . However, With the increase in intensity until 85% and then 100% of V O 2 m a x , the calpainopathy-like model induced a marked switch to the glycolysis when compared to the control model with the decrease and then disappearance of all other sources of fuel . Taken as a whole, our calpainopathy-like model highlights that, with an equivalent source of nutrients when compared to the control model, energetic metabolism is no longer able to produce large amounts of ATP at a proper rate despite a switch in energy pathways proportion, suggesting the need to improve the nutrient uptake to compensate. Section title: Calpainopathy-like muscle cell's metabolic model under different energetic demands Educational score: 4.3325910568237305 Domain: biomedical Document type: Study Language: en To better understand the disease-induced adaptation, we then ran a FVA analysis on selected enzymatic reactions from the main energy pathways at each intensity of energy demand that we plotted with the values of flux given by FBA results . This allows us to evaluate the adaptability of the system and its capacity to modulate its flux level by showing the range of values that the flux of the enzyme of interest could take without changing the optimal value of the objective function (ATP production). This FVA-given range enables the solution to be adjusted and highlights possible compensations. Interestingly, our calpainopathy-like model showed a complete disappearance of any variability in enzymatic fluxes when compared to the control model from 65% of V O 2 m a x , suggesting that under disease condition and common nutrient entry, we have only one solution to produce the highest amount of biomass. This unique solution per intensity highlighted an equal level of glycolysis between calpainopathy-like and control models over the different intensities in energy demand, noted by the aldolase flux, followed by a global limitation in oxidation power: limitation in TCA, β -oxidation, and PDH fluxes. In compensation, at 100% of V O 2 m a x , the lactate production (lactate dehydrogenase) has increased from 0.3 to 1.5 μ m o l . g D W − 1 . m i n − 1 in the calpainopathy-like model compared with the control model. This result suggests that the limitation of the oxidation capability of the model attempts to compensate through an increase in the anaerobic lactic metabolism but failed due to limited nutrient entry for a less powerful energy pathway. Taken as a whole, this modelling can not only anticipate the energy capabilities of a pathological condition, but can also highlight potent needed adaptations to compensate, leading to potential compensatory mechanisms to test. Figure 3 Plot of FBA solutions (dots) with the range of variability given by FVA solutions (blurred colour) for fructose biphosphate aldolase (aldolase, glycolysis), pyruvate dehydrogenase (PDH, glycolysis), lactate dehydrogenase (LDH, glycolysis), 3-hydroxyacyl-CoA dehydrogenase (HADH, β -oxidation), acetyl-CoA acyltransferase 2 (ACAA2, β -oxidation) and citrate synthase (CS, TCA cycle). Values are given according to the energy demand expressed as a percentage of maximal O 2 consumption, in the control (left) and calpainopathy-like (right) models. Figure 3 Section title: Exploring compensation mechanism for ATP production in calpainopathy-like model Educational score: 4.337075233459473 Domain: biomedical Document type: Study Language: en Our pathological model relies on disease-induced enzymatic flux constraints and the set of nutrient influx upper-bounds. When we applied the same upper-bound of the different nutrients for the calpainopathy-like model as the control model, we observed a limitation in ATP production from 65% of V O 2 m a x , without any glycolysis increase to compensate despite the elevation of aldolase upper-bound known in the literature. This suggests that the calpainopathy-like model could partly compensates its failure in producing energy by increasing its nutrient uptake. To demonstrate this hypothesis, we experimentally tested to remove the intake upper-bound of nutrients, nutrient per nutrient, for the calpainopathy-like model only, and we compared their capacity to compensate for the ATP production failure over each intensity of energy demand . As expected, removing the upper-bound of fatty acids uptake didn't improve ATP production as the β -oxidation was already at its maximum capacity , with an identical Root Mean Square Error (RMSE) when compared to the control model than without removing the fatty acids upper-bound . However, if removing the upper-bound of ketone bodies didn't affect the ATP production (data not shown), removing them for glucose uptake allowed to fully correct the ATP production at 65% of VO2max, and enhanced the ATP production at higher intensity without matching the control model. This adaptation decreased the RMSE to 13 . When we removed upper-bounds of glucose and glycerol, we allowed the calpainopathy-like model to quietly fully recover the ATP production capacity, with RMSE at 2 , while adding the remove of amino acid upper-bound finished to correct the metabolic state . Our modelling suggests that despite enzymatic constraints, the calpainopathy-like model can compensate for its defect in ATP production through the combined increase of nutrient uptake, a new approach for this disease that should be evaluated in vivo . Figure 4 Plot of ATP production fluxes of the control model (grey dotted lines) compared to the calpainopathy-like model (red dotted lines) depending on the energy demand from 25 to 100% of VO 2 max . Evolution of the calpainopathy-like model fluxes of ATP production under control model nutrient uptake (A), by removing upper-bound of fatty acids (B), of glucose (C), of glucose + glycerol (D) and of glucose + glycerol + amino acids (E). The root mean square error (RMSE) is calculated to estimate the distance of computed values of calpainopathy-like model with those obtained with the control model. Figure 4 Section title: Exploring compensation mechanism for ATP production in calpainopathy-like model Educational score: 4.255044937133789 Domain: biomedical Document type: Study Language: en When we focus on this restored situation to better understand the underlying mechanisms ensuring this correction, we ran an FVA analysis on the main enzymes of interest . The results showed that increasing the possibility of uptake, restored a possible variability for each flux. Confirming previous results and the necessity to increase other sources of energy, we can see here that glycolysis activity increases over time reaching its maximum activity illustrated by aldolase and lactate dehydrogenase, as well as the β -oxidation. Interestingly, not only enzyme activity of β -oxidation are limited by the regulation applied on the calpainopathy-like model, but the FVA results also show a change in reactions orientation meaning the model could produce fatty acids instead of oxidising them. When looking at the activity of the TCA cycle, we can see a decrease in citrate synthase activity from 85% of V O 2 m a x , while oxygen transport and Complex V activities are still increasing, an behaviour enabled by the increase of amino acids uptake, allowing the production of ATP to reach its objectives. Figure 5 Plot of FBA solutions (dots) with the range of variability given by FVA solutions (blurred colour) for fructose biphosphate aldolase (aldolase, glycolysis), pyruvate dehydrogenase (PDH, glycolysis), lactate dehydrogenase (LDH, glycolysis), 3-hydroxyacyl-CoA dehydrogenase (HADH, β -oxidation), acetyl-CoA acyltransferase 2 (ACAA2, β -oxidation), citrate synthase (CS, TCA cycle), ATP synthase (complex V, TCA cycle) and oxygen transport (oxygen, TCA cycle) of the calpainopathy-like model when we fully restored the ATP production rate by removing the upper-bounds of glucose, glycerol and amino acids. Values are given according to the energy demand expressed as a percentage of maximal O 2 consumption. Figure 5 Section title: Discussion Educational score: 4.314542293548584 Domain: biomedical Document type: Study Language: en In this study, we built a constraint-based metabolic model of a murine healthy skeletal muscle under different energy demands that we can adapt to various pathological or individual situations. We adjusted the upper bounds of the uptake fluxes of main nutrients (glucose and fatty acids) to match the known evolution of the proportions of energy pathways with an increase in O2 consumption and ATP production mimicking a range from 25 to 100% of maximal O2 consumption. The values for ATP production and O2 consumption were extracted from experimental values, while we determined adequate nutrient uptake. Based on this correspondence between energy production and nutrient consumption, we have a model of muscular energy production ready to be adapted to disease contexts to evaluate metabolic changes and possibly anticipate compensatory mechanisms. To this end, we focused on calpainopathy disease, the most common limb-girdle muscular dystrophy, in which complex metabolic alterations have been reported as indirect defects of the CAPN3 gene mutation. To model this pathology, we combined published dysregulations of muscle metabolism in a calpainopathy murine model and used these alterations to constrain enzyme fluxes by calculating dedicated bounds. The tune analysis of this calpainopathy-like model, not only confirmed a loss of ATP production capacity but also revealed for the first time that increasing the uptake of a combination of nutrients (glucose + glycerol + amino acids) can overcome the energy production defects. Our study not only developed mitochondrial bioinformatic models but also showed that we can use such models to orientate preclinical and clinical research, creating an adaptive tool for personalised medicine. Section title: Discussion Educational score: 4.4373579025268555 Domain: biomedical Document type: Study Language: en Our study is the first attempt to model dystrophic disease with secondary metabolic alterations using a constraint-based method. This unique approach allowed us to mimic in vivo energy production defects with altered metabolic pathways instead of blocked ones. The increase and decrease of enzymatic activity related to a specific disease context is of paramount challenge, knowing that for an equivalent enzymatic quantity, its activity can be multiplied under specific cellular contexts, such as a decrease in ATP content and/or a change in the amount of cofactors. This leads us to consider two priorities for the model: 1. a drastic change in energy demand to simulate changes in muscle fate under different conditions of use; 2. the use of FBA and FVA allowing a range of enzymatic fluxes. The combination of these two parameters opens new avenues for further research in the field. As a proof of concept of the interest of such an original approach, we used calpainopathy as a pathological context to constrain the model. Interestingly, thanks to the modelling of a gradual increase in energy demand, we were able to objectify the muscular defect in ATP production while at rest the modelled cell did not show any defect. Moreover, this approach also highlighted the imbalance between pathways that change for each percentage of energy demand, revealing the complexity of cellular adaptation and providing a precise guide for experimental research. However, of the three enzymes known to be up-regulated in calpainopathy, two were represented in the model (lactate dehydrogenase and fructose biphosphate aldolase), and only lactate dehydrogenase flux was used at its potential compared to the control at 100% of V O 2 m a x (see supplementary table S2), suggesting a compensatory overuse of the anaerobic lactic acid pathway in this disease context. The value of fructose-biphosphate aldolase flux, an enzyme that catalyses the first steps of glycolysis, remained the same as control at all levels of energy demand, consistent with fixed glucose uptake and thus limiting potential compensations. If this could highlight the limitations of the FBA method due to its dependence on fixed nutrient uptake, it also demonstrates its ability to focus on blocking steps of energy metabolism, opening up compensatory mechanisms to decipher. This hypothesis is also confirmed by the FVA analysis , which shows little variability for the resting state and none for the other states with higher energy requirements. Disease-induced regulations we used to build the model, therefore allowed only one solution and no alternative pathway, meaning there is no possible adjustment with the first set of parameters fixed. The calpainopathy-like model is therefore a constrained model offering little to no flexibility compared to the control model. However, it's well known that the nutrient uptake capacity of a cell can vary under different conditions, pathological or under treatment or exercise training. Importantly, when we modulated the nutrients uptake fluxes of the model, to observe compensation and reduce the current ATP deficit, FVA showed a return of enzymatic flexibility allowing the diseased model to produce more ATP and to adapt differently to a change in ATP consumption rate. This result not only pushes the preclinical research to focus on muscle uptake capacity but also open avenues for therapeutic approaches to improve glucose uptake, including physiotherapy. Section title: Discussion Educational score: 4.256694793701172 Domain: biomedical Document type: Study Language: en By first increasing the glucose and FA inputs, we were able to confirm that β -oxidation had already reached its maximum activity, as the increase in FAs didn't change the lack of ATP production, illustrating the inability of the muscle to trigger the expression of genes associated with fatty acid metabolism after exercise . Since β -oxidation and the mitochondrion are limited by regulation, the model should be able to produce more ATP via the anaerobic-lactic pathway to compensate. This is indeed the case at all intensities, allowing greater ATP production than with the baseline glucose value and even reaching ATP demand at 65% of V O 2 m a x . However, glycolysis is limited both by the constraints applied to fructose-biphosphate aldolase (maximum flux of 2.66 μ m o l . g D W − 1 . m i n − 1 ) and by those applied to lactate dehydrogenase (maximum flux of 2.05 μ m o l . g D W − 1 . m i n − 1 ), values that are reached for a glucose input flux of 3 μ m o l . g D W − 1 . m i n − 1 at 85% and 100% of V O 2 m a x . Section title: Discussion Educational score: 4.244068622589111 Domain: biomedical Document type: Study Language: en It might be tempting at first to try to remove these limitations in order to improve the anaerobic lactic pathway. However, increasing lactate production may not be a viable solution, as several diseases are characterised by an excess of lactate production, which we generally try to avoid as it may lead to lactic acidosis . So although these results showed a corrective potential through glycolysis, increasing glucose uptake flux alone is not enough to compensate for the lack of ATP production. Therefore, in addition to the variation in glucose, we also allowed variation for other energy sources by increasing their possible uptake. Increasing amino acid uptake alone allowed compensation, but their flux values were well above what could be found in the literature, with a 5 fold . By combining ketone bodies, glycerol and amino acid uptake, we were able to address this problem and show ATP production compensation within a more consistent range. Our study has demonstrated the potential of multiple pathway combinations to compensate for disease alterations and to reinforce the interconnection of the metabolic pathways, especially in the context of mitochondrial dysfunction, a common feature of numerous neuromuscular disorders. Section title: Discussion Educational score: 4.486557960510254 Domain: biomedical Document type: Study Language: en To characterise oxidative phosphorylation activity, we analysed key metrics such as the rate of oxygen consumption and ATP synthesis, which are essential indicators of mitochondrial function. Concerning the design of the control model and its functioning under gradual energy demands, knowing the ATP consumption rate over different O2 consumption rate was not sufficient to mimic physiological muscular function. The FBA-based model failed to produce the required ATP or balance the metabolic pathways at the published nutrient limits. As O2 and ATP consumption increases, muscle cells use different metabolic pathways according to their respective “power”, i.e. their respective ability to produce a certain amount of ATP per unit of time. If β -oxidation is defined as the most efficient pathway, the number of subsequent enzymatic steps to produce ATP slow down their capacity which then has to be compensated by glycolysis, less effective but much faster. Unfortunately, our model failed to mimic this physiological adaptation pushing us to search for proper nutrient boundaries ensuring the match between energy demand and the known proportions of the main metabolic pathways. This manual adjustment of the control model highlight FBA approach limitations which should be addressed by combining other computational calculation to properly anticipate the special cases we would model. To enhance our approach, integrating genome-scale metabolic models with transcriptomics data, facilitated by tools such as COBRApy, could offer a more comprehensive view of cellular metabolism. This integration would allow for more accurate predictions of metabolic fluxes, leading to better constraints on nutrient uptake rates and more reliable metabolic behaviour predictions. Recently, a machine learning method has been proposed to learn and generalise statistical patterns between input conditions and output reference fluxes. However, these models still suffer from the lack of experimental data set to train. Moreover, it is worth noting that our method does not take into account the concentration of either the metabolites or the enzymes. Knowing the kinetic parameters could allow us to find more accurate uptake values, in particularly the glucose uptake, and to predict the variation of enzymatic activities for possible therapeutic targets. However, calculating the concentration of metabolites and enzymes in metabolic networks is a challenging task due to the non-linear nature of enzyme kinetics. When including non-linear enzyme kinetics into models that contain alternative pathways, the solution space is no longer convex, making such problems extremely difficult to solve computationally. One approach to address this challenge is the Enzyme Cost Minimization algorithm, which identifies the set of metabolite concentrations that minimise the total enzyme mass required to sustain a pre-determined flux through a single pathway. To find the optimal pathway in metabolic networks , all elementary flux modes (EFMs) must be computed. However, the number of EFMs increases combinatorially for large-scale networks. Even if the computation of relevant EFMs that respect diverse linear and boolean constraints is possible with a large set of constraints , the identification of all the kinetic parameters is challenging , . Section title: Discussion Educational score: 4.199411392211914 Domain: biomedical Document type: Study Language: en To validate and refine our model predictions, several experimental approaches can be employed. One key method involves combining oximetry measurements with ATP production rate assessments on isolated mitochondria from human biopsies or animal model muscles . Additionally, direct enzymatic activity measurements of key reactions in the muscular energy pathways of interest can be performed. For instance, assessing the activities of phosphofructokinase and hexokinase would provide valuable data on glycolytic flux. These experimental approaches would not only serve to validate our model's predictions but also provide new data to further refine and improve the model's accuracy. Furthermore, these experimental validations could be extended to compare healthy and calpainopathy-affected tissues, allowing us to verify the predicted metabolic alterations and potentially identify new therapeutic targets. By iteratively integrating experimental data and model predictions, we can develop a more comprehensive understanding of energy metabolism dysregulations in calpainopathy and potentially other neuromuscular diseases. Section title: Discussion Educational score: 3.978001117706299 Domain: biomedical Document type: Study Language: en In conclusion, our pioneer approach intends to be a generic model of murine muscle metabolism, making it suitable for any pathology with available data on regulatory enzyme activities. Our method operates automatically, and can be continuously optimised with experimental enrichment of clinical data, pointing out metabolic blockage, compensatory mechanisms and opening the way to new therapeutic approach as well as to personalised medicine. Section title: Limitation of the study Educational score: 4.124441623687744 Domain: biomedical Document type: Study Language: en It is important to acknowledge that this study is based on data from only two studies, with different kind of cells, and in various kinds of experiments (RNAseq and enzymatic activities). This reflects the current scarcity of quantitative data on metabolic alterations in calpainopathy. Thus, the computed calpainopathy-like model may not reflect all cases of the different variations of the disease, but despite this limitation, our work serves as a prof-of-concept, showing how constraint-based modelling can integrate available experimental data to generate testable hypotheses about disease mechanisms and potential therapeutic approaches. As this is meant to be an upgradeable model, designed to guide the biology researcher, it can then easily be supplemented with new enzymatic activity, or expression data, by adding the type of regulation to be taken into account to the existing list. Therefore analyses were carried out in this study to validate similar behaviours of the metabolism of a calpainopathy muscle cell, but this approach could be adapted to other neuromuscular diseases, providing a valuable tool for understanding metabolic dysregulations and guiding therapeutic strategies. Section title: Material and methods Educational score: 3.173881769180298 Domain: biomedical Document type: Study Language: en This study was carried out using the MitoCore model , which was originally built to represent the metabolism of a human heart cell mitochondrion and therefore does not correspond exactly to the model needed. MitoCore includes 485 reactions covering all parts of central carbon metabolism. Section title: Fitting MitoCore to murine metabolism Educational score: 4.017953872680664 Domain: biomedical Document type: Study Language: en The first step to adjust this model to our study was to assure each reaction represented in MitoCore existed in mice metabolism. In order to do that, we took the KEGG ID associated to each reaction in our model, requested through the KEGG API the EC-number associated to the enzyme catalysing the reaction and checked the presence in murine in the BRENDA database. In the set of reaction of MitoCore, 7 didn't get an entry in BRENDA and 39 didn't exist in murine, but after manually checking in literature, only one of them did not have clear evidence to support its existence, and was therefore removed of the model: the 4-acetamidobutyrate deacetylase. Section title: Computation of carbon source allocation in muscle during exercise Educational score: 4.173597812652588 Domain: biomedical Document type: Study Language: en In this study, we chose to build our healthy skeletal muscle cell model using only a constraint-based approach, without employing additional pipelines . This decision allowed us to simulate the metabolic activity of skeletal muscle under varying energy demands, capturing key pathways such as oxidative phosphorylation and glycolysis. By applying generalised physiological constraints, we were able to explore core aspects of energy metabolism relevant to both healthy and disease conditions, without relying on tissue-specific omics data, which is required to build highly specialised models like those automatically generated. Several studies discuss the effects of physical exercise on skeletal muscle metabolism, but a smaller number include precise measurements of metabolite production and consumption , . These measurements describe the flux of ATP produced and the proportion of pathways contributing to this production for different percentages of V O 2 m a x . The proportions of glycolysis and fatty acids degradation expected for the healthy model are summarised in the Table 2 . Table 2 Requirements of metabolic pathway percentages between glucose and fatty acid sources, and sets of ATP production fluxes associated with O 2 absorption fluxes for all energy demands of physical exercise. The fluxes are expressed in μmol.gDW −1 . min −1 . The literature-based constraints were used to run the FBA, while the pathways percentages were used to validate the model behaviour. Table 2 Intensity of exercise (percentage of V O 2 m a x ) 25% 65% 85% 100% Pathways percentages Glycolysis 40% 50% 80% 100% β -oxidation 60% 50% 20% 0% Literature-based constraints O 2 absorption -3.7 -7.9 -11.1 -14 ATP production 14.6 36.52 54.8 75 Section title: Computation of carbon source allocation in muscle during exercise Educational score: 3.59712290763855 Domain: biomedical Document type: Study Language: en Among the flux values of the absorbed metabolites, only oxygen values could be found , describing maximum oxygen consumption as a function of different exercise intensities in untrained rats. The values used as constraints on the models will therefore be those for oxygen consumption and ATP production also summarised in Table 2 . Section title: Computation of carbon source allocation in muscle during exercise Educational score: 4.143579483032227 Domain: biomedical Document type: Study Language: en To determine the uptake of glucose and fatty acids for a given ATP production and O2 absorption respecting the proportions of carbohydrate oxidation (CHO) and β -oxidation in the Table 2 , an optimisation problem has to be solved, computing a flux distribution for a maximal ATP production. We then computed the maximal uptake of glucose with FVA and decrease this value until the wanted proportions were reached. As the glucose uptake decreases, the fatty acids uptake increase to reach the maximal ATP production, allowing to find the right balance of pathways proportion. Section title: Calpainopathy data Educational score: 4.03057861328125 Domain: biomedical Document type: Study Language: en Metabolic dysfunctions were gathered from different studies. The first part of the regulations was measured on C57BL/6 mice , five of those consist of differential gene expression in plantaris muscle cells, between the control and the calpainopathy mice. For RNAseq data, it was assumed that only the maximal enzymatic activity was proportionally linked to the total gene expression to be used for model construction. Two regulations were taken from the same study but consist of frozen muscles glycolytic enzymes activities at 25 °C and particularly the difference of activity between the control and the calpain-3 knock-out cell. Section title: Calpainopathy data Educational score: 3.9529664516448975 Domain: biomedical Document type: Study Language: en The second part of the regulations was measured on immortalised muscle cell cultures from C57BL/6 mice grown at 33 °C and consisted of differential gene expression in myoblasts and myotubes. The temperature difference comes from the fact that the first study focused on measuring enzyme activities, while the second study set the temperature solely for cell growth, which did not influence gene expression. Section title: Calpainopathy data Educational score: 3.9503049850463867 Domain: biomedical Document type: Study Language: en And finally there are some reactions that are known to be subject to metabolic defaults such as the oxidation of fatty acids (Hydroxyacyl-Coenzyme A dehydrogenase) and their use for ATP production , and mitochondrial dysfunction. Although there are multiple cases regarding the activity of Citrate Synthase in calpainopathy (increase, decrease or no significant change), as mitochondrial dysfunctions are known to exist, a warning has been placed on the enzyme which translates as a limitation of its activity. Section title: Solvers Educational score: 4.181673049926758 Domain: biomedical Document type: Study Language: en The flux distributions to optimise energy production are carried out using Flux Balance Analysis (FBA) , , a mathematical approach that involves creating a mathematical model of the metabolic network and then using this model to predict the flux of metabolic molecules within the cell. Using COBRApy , an object-oriented Python library that provides the main COBRA methods and facilitates the representation of metabolic pathways and gene expression, the strategy is to maximise the ATP production, while constraining the dioxygen fluxes associated to each exercise intensity, and to infer glucose and fatty acid fluxes absorption that couldn't be found in the literature. The results relying on FBA solutions are deterministic regarding the constraints. Thus, repetition of the calculation always gives the same values for identical constraints, as optimal qualitative values. Section title: Solvers Educational score: 4.092805862426758 Domain: biomedical Document type: Study Language: en In the case of multiple solutions that maximise the objective function, FBA offers one that may not be the one previously expected. To compute an alternative solution, Flux Variability Analysis (FVA) is a method that provides a range of possible flux values for each reaction of the model, while maintaining the state of the network and thus satisfying the core optimisation problem of FBA. FVA offers a more complete view of the behaviour of the metabolic network, enabling variability and potential regulation points to be identified. The reaction bounds can then be modified accordingly to adjust the optimal solution, to approximate the characteristics of the different conditions studied. Section title: CRediT authorship contribution statement Educational score: 0.9620220065116882 Domain: other Document type: Other Language: en Camille Siharath: Writing – original draft, Software, Methodology, Formal analysis, Conceptualization. Olivier Biondi: Writing – original draft, Methodology, Formal analysis, Conceptualization. Sabine Peres: Writing – original draft, Software, Methodology, Formal analysis, Conceptualization. Section title: Declaration of Competing Interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Other | biomedical | en | 0.999997 |
PMC11698930 | Section title: Introduction Educational score: 3.874675989151001 Domain: biomedical Document type: Other Language: en Gastric ulcer is a lesion in the mucosa of the stomach lining that penetrates through the submucosa and sometimes to the muscularis propria and extends more than 5 mm in diameter. When alterations occur to the defense mechanisms of the stomach, it can cause changes in the gastric mucosa which will eventually result in erosion and then ulceration . Gastric ulceration is a benign lesion on the mucosal epithelium upon exposure of the stomach to excess acid and aggressive pepsin activity. It is the most prevalent gastrointestinal disorder ever known, accounting for an estimated 15 mortality out of every 15,000 complications yearly in the world . Section title: Introduction Educational score: 4.1418681144714355 Domain: biomedical Document type: Review Language: en The use of Nonsteriodal Anti-inflammatory Drugs (NSAIDs) is the second most common cause of Peptic Ulcer Disease (PUD) with H. pylori infection being the first. The secretion of prostaglandin normally protects the gastric mucosa. NSAIDs block prostaglandin synthesis by inhibiting the COX-1 enzyme, resulting in decreased gastric mucus and bicarbonate production and a decrease in mucosal blood flow. Epigastric pain usually occurs within 15–30 min following a meal in patients with a gastric ulcer . As a result of indiscriminate use of NSAIDs by people without prescription and not taking cognizance of what they eat, it accounts for over 90 % of all ulcers and approximately 25 % of NSAID users will develop peptic ulcer disease. Aspirin users are also twice as likely to develop peptic ulcers as the general population . Despite the availability and use of most orthodox and conventional drugs, gastric ulcer still remains a global health challenge because they do not total undo the effect of NSAIDs. Also, not everybody likes taking the conventional drugs and not every patient can afford them. That is why gastric ulcer is still prevalent in most developing countries in which Nigeria is one of them . Hence, the search for newer and efficacious approach to its management continues. Section title: Introduction Educational score: 4.04172945022583 Domain: biomedical Document type: Study Language: en Yogurt is abundant in calcium, zinc, B vitamins, and probiotics; it is a good source of protein; and it may be supplemented with vitamin D and additional probiotics associated with positive health outcomes . Probiotics are known to have beneficial roles in curing antibiotic associated diarrhea, constipation, traveler's diarrhea, food allergies and cancer . According to Momoh et al. , the consumption of unsweetened yogurts (containing probiotics) may improve glucose metabolism to a degree, but is more effective in treating gastrointestinal complications. The benefits of yogurt consumption to gastrointestinal function are most likely due to effects mediated through the gut microflora, bowel transit, and enhancement of gastrointestinal innate and adaptive immune responses . We therefore seek to look at the antioxidative and anti-inflammatory effects of yoghurt in gastric ulceration. We also seek to determine the effective percentage concentration of the yoghurt on gastric ulceration. Section title: Drugs and reagents Educational score: 1.1501528024673462 Domain: biomedical Document type: Other Language: en Indomethacin and Omeprazole were purchased from Ningbo DHY Pharma. Co. Ltd. China. Pasteurized yoghurt was purchased from Uche care Pharmaceutical, Ondo State, Nigeria. Section title: Drugs and reagents Educational score: 1.2412160634994507 Domain: biomedical Document type: Other Language: en The instruments (dissecting set, pH meter, dissecting microscope, electrical weighing balance, plastic cages, e.t.c.) used in this study were obtained from the Department of Physiology, Faculty of Basic Medical Sciences, University of Medical Sciences, Ondo town, Nigeria and Federal University of Technology (FUTA), Akure, Ondo State, Nigeria. Section title: Experimental animals Educational score: 3.9927029609680176 Domain: biomedical Document type: Study Language: en Thirty (30) rats weighing (100–150g) each were purchased from Mctemmy concepts laboratory animals for research and a disease-free animal farm in Osogbo, Osun state, Nigeria. The animals were kept in polypropylene plastic cages and maintained at normal and standard laboratory conditions of temperature (28 ± 2°C) and relative humidity (46 ± 6 %) with 12-h light-dark cycle and adequate ventilation for two weeks to allow for acclimatization to their new environment. The rats were weighed to ensure that none of them was outside their initial weight of 100–150g was lost. The entry point weight range was chosen to ensure that all the rats were matured enough for the laboratory experiment. The rats were fed with commercially available standard rat feed (Ladokun feeds Nig. Ltd) purchased from a commercial branch depot in Ondo city, Ondo state. They were given water ad libitum during the period of acclimatization. They were cared for and maintained in the animal facility in accordance with regulations, guidelines and policies governing the use of animals in research as described in public health service policy on human care and use of laboratory animals and approved by the University of Medical Sciences Animal Research Ethics Committee (UAREC) with approval number/ethical consent code UNIMED-AREC/Apv/2023/029. Section title: Experimental design Educational score: 3.8873417377471924 Domain: biomedical Document type: Study Language: en The rats were divided into 5 groups of 6 animals each and pre-treated as stated below: Group 1 (Control, n = 6): pre-treated with distilled water for 14 days Group 2 (Indomethacin, n = 6): pretreated with distilled water for 14 days and thereafter administered with single dose of indomethacin (40 mg/kg) . Group 3 (50 % yoghurt, n = 6): pretreated with 50 % diluted yogurt for 14 days and thereafter administered with single dose of indomethacin (40 mg/kg). Group 4 (100 % yogurt, n = 6): pretreated with 100 % yogurt for 14 days and thereafter administered with single dose of indomethacin (40 mg/kg). Group 5 (Omeprazole, n = 6): pretreated with omeprazole (20 mg/kg) for 14 days and thereafter administered with single dose of indomethacin (40 mg/kg). Section title: Ulcer induction Educational score: 4.017086029052734 Domain: biomedical Document type: Study Language: en Gastric ulceration was induced in the animals according to the procedure described by Akpamu et al., 2013. Rats were administered with a single oral dose of indomethacin (40 mg/kg body weight). They were deprived of food but had free access to water 24 h prior to ulcer induction. Various degrees of ulceration have manifested 4 h after indomethacin administration. Section title: Sample collection Educational score: 4.02100944519043 Domain: biomedical Document type: Study Language: en After the period of the experimental procedures, the animals were euthanized by cervical dislocation after being fasted for 24 h with free access to water. Retro-orbital blood collection was done and kept in plain sample bottles to obtain serum for anti-inflammatory assays and the stomach was carefully dissected out. The stomach was thereafter divided into two, a part for histological evaluation and the other part for biochemical assays. Section title: Ulcer scoring index (USI) Educational score: 4.100750923156738 Domain: biomedical Document type: Other Language: en It is a complex process that involves evaluating the size, depth, tissue type, presence of necrosis, exudate, and surrounding skin condition of the ulcer, among other factors. The USI is based on several factors that are known to affect the severity and healing of gastric ulcers. These factors include the size of the ulcer, the depth of the ulcer, the presence of necrotic tissue, the type of tissue in the wound bed, the presence of exudate or drainage, and the surrounding skin condition. Each factor is assigned a score based on its severity, and the scores are added together to give an overall USI score. The USI scoring system is as follows: • Size: Measure the length and width of the ulcer in centimeters. Multiply the length by the width to get the ulcer area. Assign a score based on the area of the ulcer: ✓ Less than 1 cm: 1 point ✓ 1–5 cm: 2 points ✓ 6–10 cm: 3 points ✓ More than 10 cm: 4 points • Depth: Determine the depth of the ulcer. Assign a score based on the depth of the ulcer: Section title: Ulcer scoring index (USI) Educational score: 3.15926194190979 Domain: biomedical Document type: Other Language: en Once each category is evaluated and scored, the individual scores are added up to determine the total ulcer score. A higher total score indicates a more severe gastric ulcer . Section title: Histological preparation and scoring Educational score: 4.106123924255371 Domain: biomedical Document type: Study Language: en A part of the stomach tissue was kept in 10 % buffered formalin and thereafter embedded in paraffin. The sections (5 μm) were and stained with routine Hematoxylin and Eosin (H&E) protocol. The slides were observed under the light microscope and a semiquantitative scoring was done by modifying the scoring system of Turkyilmaz et al., 2019. The histological changes that occurred at the gastric mucosa were scored by observing the following; loss and architectural disruption in crypts, edema, vascular congestion and infiltration of polymorphonuclear cells and lymphocytes modified using a grading of normal, mild, moderate and severe and was given a score of 0, 1, 2 and 3 respectively. Section title: Histological preparation and scoring Educational score: 3.29475998878479 Domain: biomedical Document type: Study Language: en Determination of Malondialdehyde (MDA), Superoxide dismutase (SOD), Catalase and Glutathione peroxidase in stomach tissues. Section title: Histological preparation and scoring Educational score: 4.152410984039307 Domain: biomedical Document type: Study Language: en The stomach tissues prepared for biochemical assays were homogenized in Tris KCl buffer (pH 7.4) and thereafter centrifuged to obtain a clear homogenate. Lipid peroxidation assay was done by determining Malondialdehyde (MDA) activity according to the method of Varshney and Kale . This method is based on the reaction between 2-thiobarbituric acid and MDA resulting in a pink solution which can be read at absorbance of 532 nm. Catalase (CAT) activity was performed according to the method of Sinha, 1971. The method is based on the reduction of dichromate in acetic acid to chromic acetate when heated in the presence of H 2 O 2 . The end product gives a deep green color which is read at 560 nm. Superoxide dismutase (SOD) activity was measured using the method described by Misra and Fridovich . The method is based on the ability of SOD to inhibit the auto-oxidation of epinephrine at pH 10.2. Section title: Total anti-oxidative capacity (TAC) in serum Educational score: 4.093384265899658 Domain: biomedical Document type: Study Language: en Total antioxidant capacity was determined according to the method described by Rubio et al., 2016. The method employed the use of ferric reducing antioxidant power (FRAP) assay and the principle is based on the reduction of ferric-tripyridyltriazine complex (Fe 3+ -TPTZ) reagent to ferrous tripyridyltriazine (Fe 2+ -TPTZ) by the antioxidants present in the sample at low pH. Ferrous tripyridyltriazine (Fe 2+ -TPTZ) has a blue color and can be read at 593 nm. Section title: Tumor necrosis factor-alpha (TNF-α), interleukin 10 (IL-10), Interleukin-1 beta (IL-1β) in serum Educational score: 3.733461856842041 Domain: biomedical Document type: Study Language: en Tumor Necrosis Factor-alpha (TNF-α), Interleukin 10 (IL-10) and Interleukin 1 Beta (IL-1β) were quantified using enzyme-linked immunosorbent assay (ELISA) kits purchased from Elabscience, Houston, Texas, United state and the manufacturer's instruction followed appropriately. Section title: Statistical analysis Educational score: 2.80127215385437 Domain: biomedical Document type: Study Language: en Data was analyzed using statistical software; Graphpad prism (version 9). Statistical significance was assessed using oneway analysis of variance (ANOVA) with Turkey (Post hoc test). P values of <0.05 were considered statistically significant. Results (all mean values) were expressed as group Mean ± SEM (Standard Error of Mean). Section title: Effect of on gross appearance and ulcer score Educational score: 3.7641818523406982 Domain: biomedical Document type: Study Language: en The control group showed normal mucosa with no visible lesion. The administration of Indomethacin resulted in severe ulcer in indomethacin group compared resulting in a very high ulcer scoring index the control group. The ulcer scoring index was significantly decreased in both Yoghurt groups compared to indomethacin group as the both showed mild ulceration . Section title: Effect of yoghurt on histological observations and score Educational score: 4.152953147888184 Domain: biomedical Document type: Study Language: en Histological sections revealed normal architecture of the crypts in the control group from the mucosa to the serosa layers. However, severe crypt disruption, edema and infiltration of inflammatory aggregates were observed in indomethacin (40 mg/kg) group following indomethacin administration. These changes were mild in yoghurt groups and moderate in omeprazole group as shown in Fig. 2 . Fig. 3 furthermore showed an increase in histology score in indomethacin (40 mg/kg) group compared to control group. This score was significantly reduced in both yoghurt groups and omeprazole group. Fig. 1 Effect of Yoghurt on gross morphology and ulcer score A: Control; B: Indomethacin; C: 50 % Yoghurt; D: 100 % Yoghurt; E: Omeprazole (40 mg/kg). Values are expressed as Mean ± SEM (n = 6). ∗significant when compared to Control. # significant when compared to Indomethacin (40 mg/kg). Fig. 1 Fig. 2 Photomicrograph of stomach for respective groups X100. A (Control) All tunics appear intact and normal. Submucosa (SM) and Mucosa (M). B (Indomethacin 40 mg/kg) Severe architectural disruption of crypt. Severe inflammation and infiltration of inflammatory aggregates up to the submucosa (Black arrow). Edema in the submucosa (Red arrow) and vascular congestion (green arrow). C (50 % Yoghurt) Moderate erosion of epithelium of mucosa (yellow spanning arrow). Other tunics appear normal. Mild infiltration of inflammatory aggregates at the mucosa layer (black arrow). D (100 % Yoghurt) Mild erosion of epithelium of mucosa (yellow spanning arrow). Other tunics appear normal. Mild infiltration of inflammatory aggregates at the mucosa layer (black arrow). E (Omeprazole 20 mg/kg) Mild erosion of epithelium of mucosa (yellow spanning arrow) and vascular congestion (green arrow). Other tunics appear normal. Mild infiltration of inflammatory aggregates at the mucosa layer (black arrow). Fig. 2 Fig. 3 Effect of Yoghurt on Histological score. Values are expressed as Mean ± SEM (n = 6). ∗significant when compared to Control. # significant when compared to Indomethacin (40 mg/kg). Fig. 3 Section title: Effect of yoghurt on biochemical parameters and inflammatory markers Educational score: 4.082868576049805 Domain: biomedical Document type: Study Language: en Effect of yoghurt on biochemical parameters is depicted in Fig. 4 . Malondialdehyde (MDA) was significantly increased in indomethacin grouped compared to control group. Treatment with yoghurt and omeprazole significantly reduce MDA compared to indomethacin group. Superoxide dismutase (SOD), Catalase (CAT) and Glutathione peroxidase (GPx) where all significantly decreased after indomethacin administration in the indomethacin group compared to control. Yoghurt treatment as well as omeprazole induction significantly reverse CAT and GPx but not SOD. Fig. 4 Effect of Yoghurt on biochemical assays in indomethacin induced gastric ulceration. A: Malondialdehyde (MDA); B: Superoxide dismutase (SOD); C: Catalase (CAT); D: Glutathione Peroxidase. Values are expressed as Mean ± SEM (n = 6). ∗significant when compared to Control. # significant when compared to Indomethacin (40 mg/kg). Fig. 4 Section title: Effect of yoghurt on biochemical parameters and inflammatory markers Educational score: 4.076180458068848 Domain: biomedical Document type: Study Language: en Inflammatory markers are shown in Fig. 5 . Interleukin 1- beta, interleukin 10 and tumor necrosis factor alpha were all significantly increased in indomethacin (40 mg/kg) group compared to control group. Yoghurt groups significantly decreased these parameters compared to indomethacin (40 mg/kg) group. Furthermore, total antioxidant capacity was significantly higher in 100 % yoghurt group and control group compared to indomethacin (40 mg/kg) group. Omeprazole (20 mg/kg) and 50 % yoghurt groups showed no significant difference compared to indomethacin (40 mg/kg) group. Fig. 5 Effect of Yoghurt on inflammatory markers in indomethacin induced gastric ulceration. A: Total antioxidant capacity; B: Interleukin 1β; C: Tumor necrosis factor-α; D: Interleukin 10). Values are expressed as Mean ± SEM (n = 6). ∗significant when compared to Control. # significant when compared to Indomethacin (40 mg/kg). Fig. 5 Section title: Discussion Educational score: 4.038655757904053 Domain: biomedical Document type: Study Language: en Our study has shown that consumption of pasteurize yoghurt for 2 weeks was able to boost the immune system by decreasing inflammatory markers and decrease oxidative stress via enhancement of antioxidant enzymes in the stomach against indomethacin induced gastric ulceration. Peptic ulcer is the most prevalent gastrointestinal disease and has long been reported to occur when the gastro-aggressive factors overwhelm the gastroprotective factors . Section title: Discussion Educational score: 4.069311141967773 Domain: biomedical Document type: Study Language: en Administration of indomethacin successfully induce gastric mucosa lesion evident in gross observation of the stomach and high ulcer index of the indomethacin group. Pre-treatment with both concentrations of yogurt (50 and 100 %) resulted in a remarkable decrease in gastric mucosa damage and ulcer index that is comparable to the standard drug administered (omeprazole). Previous report has shown similar effect of yogurt in acetic acid-induced gastric ulcer where yogurt containing lactobacillus gasseri promote gastric ulcer healing . Also according to Momoh et al. , it was observed that administration of the yogurt caused cell infiltrations of the stomach wall, distinct ductile without aberrant superior or inferior diverticular of the stomach interlobular lining and well-formed stomach blood vessels. Section title: Discussion Educational score: 4.157090187072754 Domain: biomedical Document type: Study Language: en Histological observations from this study also showed deep ulcer and severe inflammation as a result of increase infiltration of inflammatory cells into the stomach. Yogurt exert cytoprotective effect on indomethacin induced gastric ulcer by decreasing gastric mucosa erosion and reducing infiltration of inflammatory aggregates. This action was more effective in the 100 % yogurt compared to the other treated groups. Yogurt has been reported to have cytoprotective effects on the gastric gland against HCl-induced acute gastric lesions and this action was exerted via their ability to promote prostaglandin production . Prostaglandins are important in the stomach to enhance blood flow and for the production of mucus and bicarbonates. Indomethacin is a potent cyclooxygenase blocker thus; the administration of indomethacin will inhibit COX which is the enzyme that catalyzes the production of prostaglandin. This will lead to decrease in prostaglandin which in turn will lead to reduced gastric mucosa blood flow, mucous and bicarbonate production as well as increase acid production thereby promoting ulcer formation . Consequently, the gastroprotective action of yogurt observe in this study can be linked to its ability to promote prostaglandin production. Section title: Discussion Educational score: 4.24324893951416 Domain: biomedical Document type: Study Language: en Oxidative stress occurs as a result of imbalance between oxidants (free radicals) and antioxidant enzymes in favor of the former, which then causes damage to tissues. It is usually associated with indomethacin induced gastric ulcer model . One major end product of lipid peroxidation is malondialdehyde (MDA) which has been widely used as a marker of oxidative stress in several disease conditions such as cardiovascular, gastrointestinal and neurodenerative disease . In this study, the level of MDA was significantly higher in the indomethacin group compared to control indicating that the administration of indomethacin resulted in lipid peroxidation and this is consistent with other reports . There was a corresponding decrease in antioxidant enzymes; superoxide dismutase-SOD, catalase- CAT and glutathione peroxidase- GPx. Yoghurt pretreatment resulted in a significant restoration of MDA level to control value and increase in the antioxidant enzymes which suggest that yoghurt has antioxidant properties. It has been reported by several studies that probiotics have direct antioxidative activities and can also modify the immune system . The effect of yoghurt on MDA could be as a result of its probiotic properties. The lactic acid bacteria present in yogurt has direct ability to scavenge free radicals and also suppress their generation . Thus, preserving the body's antioxidants defense mechanism as noted in the significant increase in antioxidants enzymes compared to indomethacin group. Superoxide dismutase (SOD) which serve as first line defense against reactive oxygen species by converting the highly reavtive O2- to a less reavtive H2O2 which is further mopped up by the actions of catalase (CAT) and glutathione peroxidase- (GPx). Furthermore, the total antioxidant capacity which measures the activities of the non-enzymatic component of the antioxidant defense mechanism was also enhanced in the yogurt treated groups. Section title: Discussion Educational score: 4.260798454284668 Domain: biomedical Document type: Study Language: en The infiltration of inflammatory aggregates such as macrophages as well as the generation of reactive oxygen species have been reported to activate pro inflammatory cytokines especially tumor necrosis factor alpha (TNF-α) and Interleukin 1 beta (IL1β) . These inflammatory cytokines are closely associated with gastric ulcer indicating the severity of the disease condition. TNF-α and IL1β production are very high at the inflammatory phase of gastric ulcer which usually decreases as healing progress . Interleukin 10 is usually considered as an anti-inflammatory cytokine. It was initially noted to be a product of the T helper 2 cells which inhibits the activation of T helper 1 cell. However, it is now known to be produced by several immune cells . Interleukin 10 regulates immune responses and maintains immune homeostasis and its reduction indicates a decrease in inflammatory process . Section title: Conclusion Educational score: 4.062986373901367 Domain: biomedical Document type: Study Language: en In conclusion, this study has observed the effect of pasteurized yogurt on gastric ulcer by assessing oxidative stress parameters, pro- and anti-inflammatory cytokines as well as histological appearance. The study demonstrated that pasteurized yogurt exerts anti-oxidative and anti-inflammatory effect in indomethacin-induced ulcerated male Wistar rats, as indicated by the decrease in IL-10, IL-1B, TNF-a, and increase in TAC level and a significant difference in the anti-oxidative parameters. These findings support the potential of pasteurized yogurt as a dietary intervention for oxidative and inflammation-associated conditions. Section title: CRediT authorship contribution statement Educational score: 0.9983426928520203 Domain: other Document type: Other Language: en O.V. Ajayi: Writing – original draft, Resources, Project administration, Methodology, Funding acquisition, Conceptualization. B.O. Omolaso: Writing – review & editing, Methodology. T.P. Omayone: Writing – review & editing, Formal analysis. A.G. Adeniran: Writing – review & editing. A.O. Adu: Writing – original draft, Data curation. O.E. Olorunfemi: Writing – original draft, Data curation. Section title: Compliance with ethical standards Educational score: 1.1462059020996094 Domain: biomedical Document type: Other Language: en The experimental procedures were approved by the UNIMED Animal Care and Use Research Ethics Committee and performed in accordance with the care and use of Laboratory Animals of the NIH Guidelines by careful handling. Section title: Limitations of the study Educational score: 2.8035340309143066 Domain: biomedical Document type: Study Language: en ● The disease model used in this study, though suitable for induction of gastric ulcer can only be used to detect the cytoprotective action and cannot be used for ulcer healing. Section title: Ethical statement Educational score: 0.9932950139045715 Domain: other Document type: Other Language: en Ethical approval for this study was obtained from the University of Medical Sciences Animal Research Ethics Committee (UAREC) with approval number/ethical consent code UNIMED-AREC/Apv/2023/029 and the study complies with all regulations. Authors declare that they have no conflict of interest. Section title: Consent to participate Educational score: 0.9750487804412842 Domain: biomedical Document type: Other Language: en All authors gave their consent to participate in this study. Section title: Consent to publish Educational score: 0.776577889919281 Domain: other Document type: Other Language: en All authors consented to the publication of this article. Section title: Funding Educational score: 0.9631010890007019 Domain: other Document type: Other Language: en The study was done with ADU and OLORUNFEMI financial contribution and did not receive any sponsorship from any agency. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Other | biomedical | en | 0.999997 |
PMC11698932 | Section title: Introduction Educational score: 4.556282997131348 Domain: biomedical Document type: Study Language: en Ticks (Parasitiformes: Ixodida) are obligate hematophagous ectoparasites of all terrestrial vertebrate classes and are vectors or reservoirs of human and animal pathogenic virus, bacteria, protozoa and fungi . Two tick families encompassing numerous genera hold considerable significance in public health and veterinary matters . Currently, there are 996 known tick species worldwide, divided into three families: approximately 774 hard tick species (Ixodidae), around 221 soft tick species (Argasidae), and the monotypic family Nuttalliellidae, which exhibits features of both families . The identification of tick fossils in amber has led to the description of two novel families: Deinocrotonidae and Khimairidae, alongside several unique genera, including Compluriscututla , Cornupalpatum , Deinocroton , and Khimaira . Most protozoan pathogens carried by ticks that affect mammals of medical or veterinary interest are classified under the order Piroplasmida (e.g., Babesia , Theileria , and Cytauxzoon ) or as haemogregarines within the Hepatozoon genus (Adeleorina: Hepatozoidae) . Section title: Introduction Educational score: 4.891787528991699 Domain: biomedical Document type: Review Language: en The Trypanosomatidae family consists of unicellular eukaryotes, including pathogens of humans and animals from the genera Trypanosoma and Leishmania , as well as Endotrypanum and Porcisia . The life cycle of these organisms is primarily characterized by the involvement of arthropod vectors from the Hemiptera and Diptera orders, with some trypanosomes involving vectors from the Siphonoptera order, and fish trypanosomes from the Arhynchobdellida (Hirudinidae, leech) order. Two subspecies of Trypanosoma brucei (i.e., Trypanosoma brucei gambiense and T. brucei rhodesiense ), along with T. cruzi and T. rangeli , as well as at least 23 species of Leishmania , including the recently described Leishmania (Mundinia) chancei, are pathogenic to humans. These pathogens cause human African trypanosomiasis (sleeping sickness), Chagas disease, and cutaneous, mucocutaneous, or visceral leishmaniasis [ , , , , , , ]. These diseases also affect domestic, feral, and wild animals. Canine visceral leishmaniasis is primarily caused by L. infantum infection, with occasional cases attributed to L. donovani or L. tropica . Trypanosoma congolense , T. evansi, T. b. brucei , T. vivax , T. simiae , T. suis , T. theileri , and, more rarely, T. godfreyi infect livestock. Trypanosoma equiperdum infects equids during mating . Additionally, Trypanosoma theileri , considered non-pathogenic to humans, is found in cattle, buffalo, and antelope worldwide . It has been infrequently linked to disease resembling nagana in specific cases involving a calf , cattle , or a cow , and it can cause illness in cattle under severe stress due to concurrent diseases or poor nutrition . Trypanosoma caninum was described in 2014 as a new species infecting dogs, typically in asymptomatic cases with low humoral immune responses . Furthermore, T. lewisi , a parasite of Rattus , is also an opportunistic parasite in humans and shares common vertebrate hosts with T. cruzi . Altogether, more than 30 million people are infected, and over 48 million cattle are at risk of contracting animal trypanosomiasis in Africa, resulting in approximately 3 million cattle deaths annually . Section title: Introduction Educational score: 4.067124366760254 Domain: biomedical Document type: Review Language: en Since the early 20th century, the transmission of protozoan parasites from Leishmania and Trypanosoma has been investigated, and more recently, molecular biology techniques (e.g., next-generation sequencing) have been employed to revisit this hypothesis . There remains an ongoing debate within the scientific community regarding the ability of ticks to transmit Trypanosomatidae parasites of medical or veterinary interest. To provide an updated perspective on this debate, we conducted a systematic review and meta-analysis with the following objectives: (i) to gather published field and experimental data on the detection of Trypanosomatidae with medical and veterinary relevance in ticks, including T. theileri , T. lewisi , and T. caninum , and to assess their capacity to act as vectors for these pathogens; and (ii) to explore factors associated with the transmission of these pathogens by ticks. Section title: Protocol and registration Educational score: 2.445719003677368 Domain: biomedical Document type: Study Language: en The current study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines . The protocol was neither registered nor published. The checklist for meta-analysis is provided as Supplementary Material (Check List S1). Section title: Information source Educational score: 2.3324227333068848 Domain: biomedical Document type: Study Language: en The systematic screening of existing literature was performed using PubMed, Google Scholar, and Web of Science (WOS) databases. Publish or Perish ( Harzing.com ), a software that retrieves and analyses academic citations was used to retrieve relevant articles from Google Scholar. Section title: Search Educational score: 4.01812744140625 Domain: biomedical Document type: Study Language: en A set of keywords was used: “Trypanosomatidae” and all species of “ Trypanosoma ” or “ Leishmania ”, known to be pathogenic for humans or animals and having medical or veterinary interest, including T. theleiri , T. lewisi and T. caninum , in combination with “ticks” “Ixodidae”, “Argasidae”, and selected tick genus (e.g., “ Rhipicephalus ”, “ Hyalomma ”, “ Ornithodoros ”). Database search was done between January 1900 and June 30 , 2023, without language restrictions. Articles reporting “Trypanosomatidae” in ticks by direct examination (e.g., culture, microscopy, immunohistochemistry “IHC”) or molecular method (e.g., conventional Polymerase chain reaction “PCR”, real-time PCR “RT-PCR”, capillary or next generation sequencing “NGS”) were included in the study. We exclude studies not in the scope of our study and reporting, i.e., those whose scope and objective are “Vaccine”, “Virus”, “Drug”, “Treat”, “Pest”, “Acaricide”, “Immunology”, “Serology”, “Serum”, “ELISA”, “Antigen”. Section title: Eligibility criteria and study selection Educational score: 4.072081565856934 Domain: biomedical Document type: Review Language: en We conducted the review in accordance with the current recommendations established in 2015 and reported our findings following the PRISMA guidelines, specifically addressing the remarks for “biological” meta-analyses . Two authors independently performed a preliminary review of the articles by examining their titles and abstracts. Articles selected by at least one reviewer were retrieved and duplicated (same bibliographical record) papers were excluded. The two reviewers then performed a second selection based on full-text analysis, resolving any disagreements through discussion with a third reviewer. Studies were considered eligible based on established inclusion or exclusion criteria. Section title: Eligibility criteria and study selection Educational score: 4.053406715393066 Domain: biomedical Document type: Study Language: en The selection of eligible articles was based on the following criteria: (1) articles addressing with the detection or transmission of Trypanosomatidae parasites of medical or veterinarian interest, including T. theleiri , T. lewisi and T. caninum , in ticks; (2) field or experimental studies; (3) no restrictions on host origin; and (4) no language restriction. The exclusion criteria included (1) certain literature categories (letters, books, and reviews); (2) studies that did not focus on ticks as vectors for Trypanosomatidae (e.g., cellular immune responses of ticks, host immunogenetic influences on tick resistance); (3) studies that did not focus on Trypanosomatidae of medical or veterinary interest; (4) studies lacking information on tick collection locations and origins; and (5) studies that did not specify the identity of tick and Trypanosomatidae species (6) studies not stating the sample size and the number of positive cases where excluded from the meta analysis. Section title: Data collection Educational score: 2.547194719314575 Domain: biomedical Document type: Study Language: en We utilized a pre-existing template to extract data from the selected articles, which two of the authors compiled into a Microsoft Excel® spreadsheet. The collected information included the authors' names, publication year, study subregion/country, tick family and species, identification methods, number of tested and positive tick samples, and detection methods. Section title: Quality assessment Educational score: 4.086719989776611 Domain: biomedical Document type: Study Language: en The quality of the selected publications was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology . The total score for each article was calculated based on the following seven criteria: (1) the tick family and species provided; (2) the identified Trypanosomatidae species; (3) the detection method used; (4) the number of tested ticks reported; (5) the number of positive ticks reported; (6) information on the prevalence of Trypanosomatidae parasites in ticks; and (7) the identity of the host from which the positive tick(s) originated. Items 1–5 were scored at 2 points each, while items 6 and 7 were scored at 1 point each. Based on the total score, each publication was classified as high quality (score = 8–12), medium quality (score = 5–7), or poor quality (score = 0–4). Section title: Statistical analysis Educational score: 4.136688232421875 Domain: biomedical Document type: Study Language: en For data related to field studies, we conducted a meta-analysis of proportions using the ‘meta’ and ‘metafor’ packages in R software version 4.3.1. A Freeman-Tukey transformation with double arc sine (PFT) was applied to convert the proportions before meta-analysis. This transformation standardizes and stabilizes the distribution variance (dat<-escalc(measure="PFT", xi=xi, ni=ni, data=dat). Due to the high heterogeneity expected in the meta-analysis, a random-effects model was employed to combine the overall effect size perform and subgroup analyses. Cochrane statistics I 2 and Q (expressed as X 2 and P , respectively) were used to assess and quantify heterogeneity. An I 2 value < 50 % indicates low heterogeneity, whereas I 2 value > 50 % signifies high heterogeneity. Meta-analysis statistics were visualized using Forest plots. The Egger test and Funnel plots were utilized to assess publication bias, and results underwent stability analysis, which evalues the impact of excluding data from any single article on the results of the remaining studies. Section title: Statistical analysis Educational score: 3.9787745475769043 Domain: biomedical Document type: Study Language: en We also carried out subgroup analyses of potential risk factors, including sampling year , continent (Europe, Asia, Africa, South America, and Iceland), host family (Canidae, Bovidae, etc.), tick genus, tick species, detection methods, parasite type, and the location in the tick's organs. Additionally we performed a meta-regression using the studied parameters as covariates to address possible sources of heterogeneity. Section title: Statistical analysis Educational score: 4.092257499694824 Domain: biomedical Document type: Study Language: en Regarding the experimental studies, many papers lack quantitative data, such as the number of ticks used in the research. To address this, we performed a meta-analysis using semi-quantitative data, specifically the detection or absence of pathogens in ticks (0: absence, 1: presence). Through this methodology, we analyzed the detection of pathogens in ticks after blood feeding, the transmission of Trypanosomatidae to uninfected hosts during blood feeding, infection following the injection of infected tick materials, vertical transmission, and transstadial passage. Statistical tests were conducted, and subgroup analyses of associated factors were performed based on tick family, tick species, donor host, receiving host, and parasite family and species. Section title: Selection process overview: curating datasets for systematic review Educational score: 4.064938545227051 Domain: biomedical Document type: Study Language: en A total of 29,592 articles were retrieved during the systematic search on multiple databases, including PubMed, Google Scholar, and WOS, . After the removal of duplicate paper (n = 21,007) and ineligible papers (n = 8,423), 166 published studies were selected . After analysis of their titles, abstracts, and detailed contents, out of those 166 articles, 94 satisfied the eligibility criteria to be included in the systematic review (84 in English and 10 in other languages i. e Portuguese, Russian …), 86 articles were eligible for the meta-analysis, of which 49 dealt with field studies and 37 with experimental studies. In addition, 46 focused on the transmission of Leishmania , while 40 are focused on Trypanosoma . Full-text Portable Document Format (PDF) files not freely accessible online were obtained through the French Development Research Institute (IRD) library. Publications in French, German, Spanish, Portuguese, Russian, and Turkish languages were handled by authors and/or native language colleagues. Fig. 1 PRISMA flowchart illustrating the process of the systematic review and meta-analysis. Fig. 1 Section title: Chronology of publications on ticks as vectors of Trypanosomatidae infecting human and animals of veterinary interests Educational score: 4.302460193634033 Domain: biomedical Document type: Study Language: en The phylum Arthropoda hosts both monoxenous and dixenous Trypanosomatidae . Sand flies (Diptera; Phlebotominae) are known biological vectors of Leishmania , with some exceptions . Other biological vectors of Trypanosoma include Diptera (e.g., tsetse flies, tabanids, and Stomoxys ), Hemiptera (e.g., triatomine ‘reduviid’ bugs), and Siphonaptera (e.g., fleas) . Although most Trypanosomatidae colonize members of the class Insecta, presumably monoxenous trypanosomatids also develop in ticks (class Arachnida) [ , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ]. Since the late 19th and early 20th centuries, field trials and experiments have been conducted to detect these parasites in ticks . The ability of ticks to transmit Leishmania parasites has been documented for quite some time . In recent years, advancements in molecular detection methods for Trypanosomatidae DNA in ticks have renewed interest in the role of ticks in the transmission of both Trypanosoma and Leishmania . Specifically, since 2010, the number of studies investigating this topic has increased significantly. Fig. 2 Temporal distribution of collected and selected scientific papers. Fig. 2 Section title: Ticks as vectors of Trypanosoma : historical aspects Educational score: 4.075125217437744 Domain: biomedical Document type: Review Language: en The hypothesis that ticks may act as reservoirs and/or vectors for human and animal trypanosomes has been investigated since the early 20th century [ , , , , , , , , , , , , , , ]. In 1972, Hoare reviewed existing data on ticks as potential vectors and concluded that ticks could not transmit trypanosomes due to the absence of infective trypomastigote forms . However, subsequent research documented the presence of various trypanosome developmental stages in ticks, including amastigotes, sphaeromastigotes, epimastigotes, and trypomastigotes, suggesting a more complex relationship between ticks and trypanosomes . Section title: Leishmania : a parasite transmitted by ticks? Educational score: 4.280483722686768 Domain: biomedical Document type: Study Language: en The hypothesis that ticks may contribute to the transmission of Leishmania emerged in the 20th century. Early experiments suggested that ticks could act as vectors for Leishmania species responsible for human and canine kala-azar ( L. donovani/L. infantum complex) in the Mediterranean region. The observation of Leishmania surviving for extended periods in the tick gut raised questions about the possibility of direct transmission . However, this hypothesis has been challenged, with conflicting evidence regarding the involvement of ticks in the L. infantum transmission cycle . In the mid-1980s, further doubt was cast on this theory, although one study demonstrated transmission during a tick's blood meal . Subsequent field and laboratory studies have detected Leishmania RNA or DNA in various tick organs, including salivary glands and ovaries, across different developmental stages (larvae, nymphs, and adults), providing additional support for the potential role of ticks in Leishmania transmission [ , , , , , , , , , , , , , , , , , , , , , , , , ]. Section title: Observations of Trypanosomatidae of medical and veterinary interest in field-collected tick specimens Educational score: 3.873325824737549 Domain: biomedical Document type: Study Language: en As detailed in the following sections, numerous field studies have been conducted to investigate the prevalence of pathogenic Trypanosomatidae in ticks. Detection of the parasite has been achieved through various methods, including direct examination (e.g., culture, microscopy), molecular tools such as Polymerase Chain Reaction (PCR), quantitative PCR (qPCR), capillary sequencing, and next-generation sequencing, as well as immunological techniques like immunochromatography. Section title: Trypanosoma carriage and prevalence Educational score: 4.353155612945557 Domain: biomedical Document type: Study Language: en Traces of Trypanosoma species of medical and veterinary importance have been reported in ticks, including T. cruzi , T. vivax , T. evansi , T. theileri , T. theileri -like, T. congolense , and T. caninum [ 49 , , , , , , , , , , , , , , ]. All these studies focused on hard tick species (Ixodidae). Most of the positive tick species belonged to four genera: Amblyomma , Hyalomma , Ixodes , and Rhipicephalus , including A. cajennense , A. longirostrum , A. variegatum , H. detritum , H. marginatum , I. ricinus , R. (Boophilus) microplus , R. (Boophilus) spp. , R. sanguineus , R. sanguineus s.l. , and Rhipicephalus sp . Conversely, other species tested negative for Trypanosoma spp. ( Table 1 ) [ 89 , 90 , , , , , ]. Ticks collected from dogs and cattle were more frequently infected by Trypanosoma compared to those collected from other domestic animals (e.g., sheep, goats, camels) or wild animals (e.g., foxes, boars). • Trypanosoma cruzi Table 1 Detection of Trypanosoma species of medical and veterinary importance in field-collected ticks. Table 1 Species Sampling year/ Publication year§ Trypansoma species Tick infection status (P/N)& Localization in the tick Detection method Host Country Continent Refs A. cajennense 2013 T. cruzi N H-Gr Microscopy, PCR Canis lupus Brazil South America 1905 T. vivax N H Microscopy Bos taurus Cuba South America 1905 T. vivax P G Microscopy Bos taurus Cuba South America 2021 T. vivax P Gr PCR, Sequencing buffalos Brazil South America A. longirostrum 1941 T. cruzi P NS NS Cercolabidae ( Arboreal porcupine ) Venezuela South America Amblyomma spp. 2013–2019 T. cruzi N Gr Metagenomics ∗ Wild ungulates Carnivores Kenya Africa A. tigrinum 2013 T. cruzi N Gr PCR, Sequencing Canis lupus Chile South America A. variegatum 2016 T. congolense P Gr Parasitological analysis, PCR Cattle Nigeria Africa Haemaphysalis spp. 2017–2018 T. evansi N Gr PCR, Sequencing Cattle India Asia H. detritum 1982 T. theileri P H Microscopy Bos taurus ; Canis lupus Algeria Africa H. dromedarii 2015–2016 T. evansi N Gr PCR ∗∗ Wild ruminants Tunisia Africa H. excavatum 2015–2016 T. evansi N Gr PCR ∗∗ Wild ruminants Tunisia Africa 1982 T. theileri; T. evansi N H Microscopy Bos taurus ; Canis lupus Algeria Africa H. lusitanicum 1982 T. theileri; T. evansi N H Microscopy Bos taurus ; Canis lupus Algeria Africa H. marginatum 2015–2016 T. evansi N Gr PCR ∗∗ Wild ruminants Tunisia Africa 1990 T. theileri P H Microscopy Bos taurus Portugal Europe 1982 T. theileri; T. evansi N H Microscopy Bos taurus ; Canis lupus Algeria Africa Hyalomma spp. 2017–2018 T. evansi N Gr PCR, Sequencing Cattle India Asia I. ricinus 2013 T. caninum P Gr Culture, PCR, Sequencing Vegetation Slovakia Europe 1979–1982 T. theileri P H Microscopy Bos taurus ; Canis lupus Switzerland Europe 2015–2016 T. evansi N Gr PCR ∗∗ Wild ruminants Tunisia Africa R. (Boophilus) microplus NS T. theileri-like P H ND Bos taurus Brazil South America 1905 T. vivax N H Microscopy Bos taurus Cuba South America 1905 T. vivax P G Microscopy Bos taurus Cuba South America NS T. vivax P Gr PCR Bos taurus Venezuela South America 2021 T. vivax P Gr PCR, Sequencing buffalo Brazil South America R. (Boophilus) spp. 2017–2018 T. evansi P Gr PCR, Sequencing Cattle India Asia R. bursa 2015–2016 T. evansi N Gr PCR ∗∗ Wild ruminants Tunisia Africa R. sanguineus 2013 T. cruzi N H-Gr Microscopy, PCR Canis lupus Brazil South America 1982 T. evansi P H Microscopy Bos taurus , Canis lupus Algeria Africa 2013 T. evansi P Gr PCR Canis lupus Brazil South America 2013 T. vivax P Gr PCR Canis lupus Brazil South America R. sanguineus s.l 2013 T. cruzi P Gr PCR, Sequencing Canis lupus Chile South America 2015–2016 T. evansi P Gr PCR Wild ruminants Tunisia Africa Rhipicephalus spp. 2013–2019 T. cruzi P Gr Metagenomics ∗ ∗ ∗ Wild ungulates Carnivores Regular domestic Kenya Africa R. turanicus 1982 T. theileri; T. evansi N H Microscopy Bos taurus ; Canis lupus Algeria Africa §: When the sampling date was not specified in the publication, the year of publication was added in italics ; & information on positivity is available in the data collection sheet in the supplementary material ; P: positive; N: negative; F: faeces ; G: gut ; Gr: whole body ; H: hemolymph ; O: ovaries ; SG: salivary glands; PCR: conventional Polymerase chain reaction, Sequencing: Capillary sanger sequencing. ∗ Wild ungulates [ Black rhinoceros ( Diceros bicornis ), white rhinoceros ( Ceratotherium simum ), buffalo ( Syncerus caffer ), elephant ( Loxodonta africana ), giraffe ( Giraffa camelopardalis ), Grévy's zebra ( Equus grevyi ), plains zebra ( Equus quagga ), hartebeest ( Alcelaphus buselaphus ), impala ( Aepyceros melampus ) ] ; Carnivores [ leopard ( Panthera pardus ), lion ( Panthera leo ), spotted hyena ( Crocuta crocuta ), wild dog ( Lycaon pictus ) ] ; Regular domestic [ farmed Boran ( Bos indicus ) and cattle ( Bos taurus ) ]. ∗∗Wild ruminants: Scimitar-horned oryx; Addax antelope; Barbary red deer; Dorcas gazelle. ∗∗∗ Wild ungulates [ plains zebra ( Equus quagga ) ] ; Carnivores [ lion ( Panthera leo ), spotted hyena ( Crocuta crocuta ) ] . Section title: Trypanosoma carriage and prevalence Educational score: 4.233328819274902 Domain: biomedical Document type: Study Language: en Since the 1940s, the prevalence of T. cruzi in field-collected ticks has remained uncertain. The presence of T. cruzi in A. longirostrum , an ectoparasite of porcupines, was documented during a survey of ectoparasites conducted in the state of Yaracuy, Venezuela . Between 2013 and 2015, ticks collected from 148 dogs in the urban area of Campo Grande, Mato Grosso do Sul, Brazil, revealed that R. sanguineus and A. cajennense were not infected by T. cruzi . More recently, the presence of T. cruzi was documented in dogs and their ectoparasites in a rural area of central Chile, where 57 % of blood samples were infected by T. cruzi , and 5.4 % of ticks tested positive by PCR. Specifically, R. sanguineus s.l. (5/82) was positive, while all A. tigrinum specimens (0/11) were negative . The same year, a study focused on using ticks as xenosurveillance sentinels to monitor circulating pathogens in the Kenyan drylands. Ticks were collected from wild ungulates, carnivores, domestic animals, and Boran cattle and screened using metagenomics. T. cruzi DNA was detected in 3 out of 46 (6.5 %) pools of Rhipicephalus spp., but not in Amblyomma spp . However, the examination of the sequences could not definitively confirm the presence of T. cruzi . • Trypanosoma vivax Section title: Trypanosoma carriage and prevalence Educational score: 4.262103080749512 Domain: biomedical Document type: Study Language: en Trypanosoma vivax infects wild and domestic ungulates and is transmitted mechanically via tabanids and other blood-sucking insects in the Americas . An analysis of the gut contents of A. cajennense (Fabricius) sensu stricto (s.s.) and R. (Boophilus) microplus (Canestrini) (Acari: Ixodidae), collected from cattle ( Bos taurus ) on two farms in Cuba, revealed the presence of living T. vivax forms 96 h after repletion, though not in the hemolymph . Of the 285 R. (Boophilus) microplus ticks collected from cattle in livestock areas of Merida, Venezuela, 7.7 % tested positive using PCR . That same year, an examination of 63 R. sanguineus ticks collected from dogs in Campo Grande, Brazil, revealed the presence of Trypanosoma spp. via PCR, with 15 (23.8 %) testing positive for T. vivax . Lastly, in a search for T. vivax in A. cajennense s.s. and R. (Boophilus) microplus collected from cattle, 6.25 % (3/48) of A. cajennense s.s. and 4.5 % (2/45) of R. (Boophilus) microplus were positive. The sequences obtained were 99 % identical to those of bovine T. vivax from northeastern Brazil . • Trypanosoma evansi Section title: Trypanosoma carriage and prevalence Educational score: 4.355398178100586 Domain: biomedical Document type: Study Language: en Trypanosoma evansi is primarily transmitted by tabanid flies and Stomoxys spp. It affects a wide range of hosts, including livestock, camelids, equids, carnivores, rodents, and humans, producing variable clinical symptoms depending on the host . In a study on the seasonal dynamics of R. sanguineus in dogs in urban areas of western Algeria, hemolymph smears were examined for potential microorganisms. Five out of 250 R. sanguineus ticks (four females and one male) were found to be infected with trypanosomes, representing 2 % of the total. Two infected females showed pathological reactions (globular bodies and milky hemolymph) related to the infection. Based on the observed form and small size of the protozoan, it was hypothesized to be T. evansi (referred to as T. berberum in the manuscript), a parasite of camelids that causes deadly trypanosomiasis in dogs . This hypothesis was further supported by a report that 15 out of 63 dogs in Campo Grande, Mato Grosso do Sul, Brazil, tested positive for T. vivax and 7 for T. evansi using PCR . In 2021, 0.2 % of the 352 ticks collected from the environment and wild ruminants in Tunisia were also reported positive for T. evansi by PCR . Finally, in India, the sequencing of 240 pooled tick-DNA samples collected from two regions revealed no prevalence of T. evansi in Karnataka but a prevalence of 8.3 % in Kerala . • Trypanosoma theileri and T. theileri-like Section title: Trypanosoma carriage and prevalence Educational score: 4.2001190185546875 Domain: biomedical Document type: Study Language: en Multiple studies have documented the presence of trypanosomes in tick hemolymph . Most of these studies identified T. theileri , which is typically transmitted by tabanid flies . T. theileri was first reported in field-collected ticks in a 1979 study conducted in Switzerland, where 0.19 % of I . ricinus were found to carry trypanosomes morphologically similar to T. theileri . Between 1979 and 1982, the presence of T. theileri in the hemolymph of ticks from Switzerland and Algeria was confirmed, with 0.24 % of H. detritum and I. ricinus ticks collected from bovines testing positive . In 2008, Martins reported the presence of Trypanosomatidae epimastigote forms in the hemolymph of the cattle tick R. (Boophilus) microplus in Rio Grande do Sul, Southern Brazil, with microscopic examination suggesting T. theileri . • Trypanosoma congolense Section title: Trypanosoma carriage and prevalence Educational score: 4.201586723327637 Domain: biomedical Document type: Study Language: en Animal trypanosomosis is a complex disease caused by one or more species of pathogenic trypanosomes, including T. congolense . Clinical symptoms are characterized by intermittent fever, parasitemia, anemia, lymphadenopathy, jaundice, progressive emaciation, weakness, and reduced productivity . Trypanosomes transmitted by tsetse flies ( Glossina spp.) are responsible for animal African trypanosomosis in sub-Saharan Africa . In 2016, trypanosomes were detected in engorged adult A. variegatum collected from cattle in the Unguwan Rimi and Kaduna state areas of northwestern Nigeria. Of the 33 samples examined microscopically, 14 tested positive for T. congolense , representing a prevalence rate of 42.4 %. On the first day of parasitemia follow-up, 10 (30.3 %) samples were microscopically positive for T. congolense , while 23 (69.7 %) were negative . • Trypanosoma caninum Section title: Trypanosoma carriage and prevalence Educational score: 4.341454029083252 Domain: biomedical Document type: Study Language: en Trypanosoma caninum , the most recently identified species within the Trypanosomatidae family, has been reported to infect dogs in Brazil . Since its description, 67 cases of natural infection in dogs have been documented in areas where canine visceral leishmaniasis is endemic . In Slovakia, a novel trypanosome was isolated and partially characterized from I. ricinus . Sequence analysis suggests that this trypanosome, referred to as Trypanosoma sp. Bratislava1, is a new species closely related to several trypanosomes isolated from or detected in ticks in South America and Asia, including T. caninum from Brazil the most recent species within the Trypanosomatidae family, was reported to infect dogs in Brazil . Despite its recent identification, 67 cases of natural infection in dogs have been documented in areas where canine visceral leishmaniosis is endemic . In Slovakia, a novel trypanosome was isolated and partially characterized from I. ricinus . The resulting sequences support this trypanosome, referred as Trypanosoma sp. Bratislava1, as a new species closely related to several trypanosomes isolated from, or detected in, ticks in South America and Asia, including T. caninum isolated in Brazil . Section title: Leishmania prevalence in field collected ticks Educational score: 4.363060474395752 Domain: biomedical Document type: Study Language: en The presence of Leishmania in ticks is well documented, including species such as L. infantum/L. donovani , L. major , L. chagasi (syn. L. infantum ), L. braziliensis , L. guyanensis , and L. martiniquensis [ 64 , , , , , , , , , , , , , , , , 97 , , , , , , , , , ]. Most field studies focus on ticks from domestic animals in urban areas, particularly R. sanguineus [ 60 , 64 , , , , 70 , 71 , 75 , , , , 87 , , , , , 108 , 109 , 111 ]. Ticks collected from more wild ecosystems have highlighted the diversity of tick species positive for the presence of Leishmania , including A. sabanerae , Amblyomma spp. , A. tigrinum , A. variegatum , Hyalomma aegyptium and H. dromedarii , Ixodes ricinus , I. spp. , I. ventalloi , R. (Boophilus) microplus , R. pusillus , R. sanguineus s.l., and R. turanicus . ( Table 2 ). • Leishmania infantum and L. chagasi (Syn L. infantum) Table 2 Detection of Leishmania species of medical and veterinary importance in field-collected ticks. Table 2 Species Sampling year/Publication year§ Leishmania species Tick status(P/N)& Localization in the tick Detection method In tick Host Detection method in the host Country Continent Ref A. cajennense 2013 L. chagasi (Syn L. infantum ) N H-Gr Microscopy, PCR Canis lupus ND Brazil South America A. ovale 2008 L. infantum N Gr qPCR Canis lupus IFAT Brazil South America A. sabanerae 2022 Leishmania sp. P Gr qPCR Pecari tajacu ; Chelonoidis denticulata ND Peru South America Amblyomma spp. 2012 L. guyanensis P Gr PCR; HRM-PCR Tapirus terrestris ; Pecari tajacu ND Peru South America A. tigrinum 2010–2013 Leishmania sp. P Gr PCR Pseudalopex griseus PCR, qPCR Argentina South America A. variegatum 2014–2015 L. martiniquensis P Gr HT-qPCR Cattle ND Guadeloupe Island D. marginatus 2007–2008 L. infantum N Gr PCR Wild boars ND Italy Europe 2007 L. infantum N Gr qPCR Canis lupus ELISA, PCR Italy Europe 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia Ha. longicornis 2012 L. infantum N Gr PCR Sheep, cattle and dog ND China Asia Ha. parva 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia Ha. punctata 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia Ha. sulcata 2007–2008 L. infantum N Gr PCR Sheep and Goat ND Italy Europe 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia H. aegyptium 2015–2018 L. infantum P Gr PCR; Sequencing Testudo graeca ; Camelus dromedarius ND Israel Asia 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia H. dromedarii 2015–2018 L. infantum P Gr PCR, Sequencing Testudo graeca ; Camelus dromedarius ND Israel Asia H. excavatum 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia H. marginatum 2007–2008 L. infantum N Gr PCR Cattle ND Italy Europe 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia Hyalomma spp. 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia I. ricinus 2007 L. infantum P Gr qPCR Canis lupus ELISA, PCR Italy Europe 2007–2008; 2010 L. infantum P Gr PCR Dog, horse, cat, bovine, human ND Italy Europe 2011 and 2013 L. infantum P Gr PCR Felis catus ND Italy Europe I. ricinus 2012–2013 L. infantum P Gr qPCR Felis catus PCR, qPCR Italy Europe 2010 L. infantum P Gr PCR; Sequencing $Flagging ND Italy Europe 2014 Leishmania sp. P Gr PCR Human ND Turkey Asia Ixodes spp. 2011 and 2013 L. infantum N Gr PCR Felis catus ND Italy Europe 2012–2013 L. infantum P Gr qPCR Felis catus PCR, qPCR Italy Europe I. ventalloi 2011 and 2013 L. infantum P Gr PCR Felis catus ND Italy Europe 2012–2013 L. infantum P Gr qPCR Felis catus PCR, qPCR Italy Europe R. (Boophilus) microplus 2012 L. guyanensis P Gr PCR; HRM-PCR Tapirus terrestris ; Pecari tajacu ND Peru South America 2012 L. infantum N Gr PCR Sheep, cattle and dogs ND China Asia Leishmania sp. P Gr qPCR Pecari tajacu; Chelonoidis denticulata ND Peru South America 2014–2015 L. martiniquensis P Gr HT-qPCR Cattle ND Guadeloupe Island 2014–2015 L. martiniquensis P Gr HT-qPCR Cattle ND Martinique Island R. bursa 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia 2007–2008 L. infantum N Gr PCR Sheep, goat, cattle, horse, deer ND Italy Europe R. pusillus 2011 and 2013 L. infantum P Gr PCR Felis catus ND Italy Europe 2007–2008 L. infantum N Gr PCR Hedgehog ND Italy Europe 2012–2013 L. infantum P Gr qPCR Felis catus PCR, qPCR Italy Europe R. sanguineus 2012–2013 L. infantum P Gr qPCR Felis catus PCR, qPCR Italy Europe 2016–2017 L. major P Gr PCR, Sequencing Rhombomys opimus ; Nesokia indica ND Iran Asia 2013 L. chagasi (syn L. infantum ) P H-Gr Microscopy, PCR Canis lupus ND Brazil South America NS L. braziliensis P Gr PCR, qPCR Canis lupus ND Brazil South America 2007 L. infantum P Gr PCR; qPCR Canis lupus IFAT, PCR, qPCR Brazil South America 2007 L. infantum P Gr-SG PCR; qPCR; sequencing Canis lupus ND Italy Europe 2008 L. infantum P Gr-SG PCR; qPCR; sequencing Canis lupus ND Brazil South America 2007–2008 L. infantum P Gr PCR Canis lupus ELISA Brazil South America 2007–2008 L. infantum N Gr PCR Canis lupus ND Italy Europe 2008–2009 L. infantum P Gr PCR, RT-PCR, Sequencing Canis lupus ELISA, PCR Brazil South America R. sanguineus 2007 L. infantum P Gr qPCR Canis lupus ELISA, PCR Italy Europe 2006–2007 L. infantum P Gr qPCR Canis lupus ELISA, PCR Italy Europe 2011–2012 L. infantum N NS Infestation Canis lupus IFAT, ELISA Brazil South America 2013 L. infantum P Gr PCR, qPCR, seuqencing Canis lupus PCR, qPCR Brazil South America 2012 L. infantum P Gr PCR Canis lupus IFAT, ELISA Brazil South America 2013 L. infantum P Gr PCR, Sequencing Canis lupus PCR, Sequencing Brazil South America 2011 L. infantum P G PCR, RFLP, seuqencing, Parasit culture Canis lupus DPP, IFAT, ELISA, PCR Brazil South America 2011 L. infantum P SG PCR, RFLP, Sequencing, Parasit culture Canis lupus DPP, IFAT, ELISA, PCR Brazil South America 2011 and 2013 L. infantum P Gr PCR Felis catus ND Italy Europe 2002 Leishmania sp. P G Microscopy Canis lupus IFAT Brazil South America 2009 Leishmania sp. N NS present of tick or no Canis lupus IFAT Brazil South America 2012–2014 Leishmania sp. N Gr qPCR Canis lupus qPCR China Asia 2015 Leishmania sp. P G; O; SG IHC, qPCR, IHC Canis lupus ND Brazil South America 2016 Leishmania sp. P G; O; SG IHC, qPCR, IHC Canis lupus ND Brazil South America 1934 £L. kala azar P NS NS Human NS France Europe 2008 L. infantum N Gr qPCR Canis lupus IFAT Brazil South America R. sanguineus s.l. NS L. infantum P Gr PCR, Sequencing $Flagging & ∗Animals ND Israel Asia R. turanicus 2007–2008 L. infantum N Gr PCR Sheep and Goat ND Italy Europe 2014 Leishmania sp. N Gr PCR Human ND Turkey Asia 2022 L. infantum P Gr PCR, Sequencing $Flagging & ∗Animals ND Israel Asia §: When the sampling date was not specified in the publication, the year of publication was added in italics ; & information on positivity is available in the data collection sheet in the supplementary material ; NS : Not specified; P: positive; N: negative; F: faeces ; G: gut ; Gr: crushing ; H: hemolymph ; O: ovaries ; SG: salivary glands; PCR: conventional Polymerase chain reaction, RFLP: restriction fragment length polymorphism; qPCR: real time PCR; RT-PCR : reverse transcriptase PCR; HRM-PCR : High Resolution Melting PCR; HT-qPCR : High-throughput microfluidic qPCR; Sequencing: Capillary sanger sequencing, IFAT: Indirect Fluorescent Antibody Test; ELISA: Enzyme Linked Immunosorbent Assay; DPP: rapid immunochromatographic test; IHC : immunohistochemistry ∗ Animals: dogs ( Canis familiaris ); Tortoise ( Testudo graeca ); hedgehogs ( Erinaceus concolor ); badger. £ L. kala azar: refers to members of the L. donovani complex ( L. infantum and L. donovani ) without any other information on parasite typing at the time of the study. We therefore use the term proposed by the author. $ Flagging : refers to the use of a method to collect questing ticks. Section title: Leishmania prevalence in field collected ticks Educational score: 4.496522426605225 Domain: biomedical Document type: Study Language: en The hypothesis that ticks could serve as vectors for Leishmania was first proposed in the early 20th century . Domestic dogs play a central role as reservoirs of L. infantum in the peridomestic zoonotic transmission cycle. The brown dog tick, R. sanguineus , has been the subject of extensive research due to its prevalence among urban dogs . The overall prevalence of L. infantum in R. sanguineus collected from dogs or cats ranges from 2.5 % to 70.3 % in Brazil and Italy. Significant L. infantum presence has been recorded in various Rhipicephalus species, including 9.2 % of R. sanguineus s.l. ticks collected by flagging (questing ticks) and 23.5 % of R. turanicus collected from dogs, hedgehogs, and tortoises in Israel . Additionally, infections were reported in R. pusillus from cats in Italy, with 10.9 % and 17.6 % positivity. Studies have also detected L. infantum in I. ricinus (1.5 %–50 %) , I. ventalloi (19 % and 62 %) , Ixodes sp. (10.9 %) , H . aegyptium (38.7 %), and H. dromedarii (55.6 %) , collected from various hosts, including dogs, horses, cats, bovines, tortoises, camels, and humans in Italy and Israel. In most of these studies, L. infantum DNA was detected in whole ticks, and in some cases, specifically in the gut or salivary glands . Leishmania chagasi (syn. L. infantum ), which causes American visceral leishmaniasis, is widely distributed across Latin America . It is believed that L. infantum was introduced to South America by the conquistadors' dogs . In Campo Grande, Mato Grosso do Sul, Brazil, two tick species, R. sanguineus and A. cajennense , were collected from dogs in urban areas. Tick samples from 36 dogs tested positive for L. infantum , all of which were R. sanguineus . • Leishmania major Section title: Leishmania prevalence in field collected ticks Educational score: 2.334031820297241 Domain: biomedical Document type: Other Language: en One R . sanguineus nymph collected from a rodent in the Segzi Plain, Esfahan Province, Iran, was tested positive for L. major . • Leishmania braziliensis Section title: Leishmania prevalence in field collected ticks Educational score: 4.0745849609375 Domain: biomedical Document type: Study Language: en American cutaneous leishmaniasis (ACL) is primarily caused by L. braziliensis . The challenges in controlling ACL may be linked to the disease's complex epidemiology, which involves various vector species, including ticks. Two rural areas in Pernambuco, northeastern Brazil, where ACL is endemic, were investigated for canine ectoparasites. Genomic DNA was extracted from 75 R . sanguineus ticks, 32 of which (42.67 %) tested positive for L. braziliensis using both conventional PCR and real-time PCR (RT-qPCR) . • Leishmania guyanensis Section title: Leishmania prevalence in field collected ticks Educational score: 4.157562255859375 Domain: biomedical Document type: Study Language: en Leishmania guyanensis is a causative agent of American tegumentary leishmaniasis. In 2017, DNA belonging to the Viannia subgenus was detected in 81 R . (Boophilus) microplus and Amblyomma ticks collected from three Tapirus terrestris and three Pecari tajacu in Madre de Dios, Peru, following amplification of kinetoplast DNA (kDNA) . Additionally, Leishmania (Viannia) kDNA was detected in three R. microplus ticks collected from a P. tajacu hunted in the forests of Madre de Dios. High-Resolution Melting PCR (HRM-PCR) identified one positive sample with a kDNA melting curve compatible with L. (V.) guyanensis . • Leishmania martiniquensis Section title: Leishmania prevalence in field collected ticks Educational score: 4.090060710906982 Domain: biomedical Document type: Study Language: en Leishmania martiniquensis was first isolated in 1995, its taxonomical classification was established in 2002, and it was officially named in 2014 [ 11 , , , ]. The vectors and reservoirs remain unidentified, although biting midges are suspected to be involved in the transmission of Leishmania species belonging to the Mundinia subgenus . In 2020, a high-throughput microfluidic real-time PCR system designed for genus-level parasite screening was applied to 132 adult specimens of Amblyomma variegatum and 446 specimens of R . microplus collected in Guadeloupe and Martinique. It was found that 0.7 % of the R. microplus ticks from Martinique tested positive for Leishmania spp., with sequences identifying L. martiniquensis . • Other/ unidentified Leishmania parasites Section title: Leishmania prevalence in field collected ticks Educational score: 4.298175811767578 Domain: biomedical Document type: Study Language: en In 2010, the presence of leishmania promastigote forms in ticks parasitizing domestic dogs was reported in the Municipality of São Vicente Férrer, located in the northern agreste of Pernambuco, Brazil . In 2015 and 2016, leishmania was detected in the intestines, ovaries, and salivary glands of R. sanguineus from dogs in Brazil, using both immunohistochemistry (IHC) and real-time PCR. IHC revealed Leishmania in 98 % of intestines, 14 % of ovaries, and 8 % of salivary glands, while real-time PCR confirmed these organs as the most positively tested sites . Additionally, Leishmania DNA, likely belonging to the L. donovani complex, was found in 11 out of 17 pools (64.7 %) of A . tigrinum ticks collected from eight foxes (six grey foxes, Pseudalopex griseus, and two culpeo foxes, P. culpaeus) in Argentine Patagonia . Although sandflies are typically found 2000 km and 750 km north of the study area, this finding suggests either a wider distribution than currently believed or the persistence of Leishmania in another vector. In 2022, 95.7 % of R. (Boophilus) microplus and 90 % of A. sabanerae collected from Pecari tajacu and Chelonoidis denticulata in leishmaniasis-endemic zones of the Peruvian Amazon were found to carry Leishmania , with parasite loads of 34.1 and 5428.6 per arthropod, respectively . Section title: Experimental infection and transmission of Trypanosomatidae by ticks Educational score: 4.087988376617432 Domain: biomedical Document type: Study Language: en In the early 20th century, laboratory experiments were conducted to assess the vector competence of ticks for transmitting trypanosomes. Several studies demonstrated the presence of various Trypanosoma or Leishmania forms—including trypomastigotes, amastigotes, epimastigotes, promastigotes, and sphaeromastigotes—in both ixodid and argasid ticks. Transmission routes were investigated, including transmission through tick bites and blood meals, as well as alternative routes such as ingestion of infected ticks, transstadial passage (between different life stages of ticks and their hosts), and transovarial transmission (ovarian infection). Section title: Transmission of Trypanosoma following tick bites and feeding Educational score: 4.136767864227295 Domain: biomedical Document type: Study Language: en The role of ticks as vectors of trypanosomes has been increasingly supported by recent studies, which provide additional evidence of the transmission of distinct trypanosome clades to various mammalian species by ticks . Several reports document the detection of Trypanosoma in ticks after blood-feeding on an infected animal in experimental settings . Trypanosomes of medical and veterinary interest have been detected in both hard and soft ticks from three genera ( Rhipicephalus , Hyalomma , and Ornithodoros ) and four species: R. sanguineus , H. a . anatolicum , O. crossi , and O. lahorensis . Experimental infections following a bite or blood meal have been reported for T. cruzi , T. evansi , and T. theileri . • Trypanosoma cruzi Section title: Transmission of Trypanosoma following tick bites and feeding Educational score: 3.4595015048980713 Domain: biomedical Document type: Study Language: en The earliest reports of dog infection by T. cruzi -infected R. sanguineus ticks date back to 1913 . However, attempts to infect rats using infected soft ticks of the genus Ornithodoros were unsuccessful . Several other studies have also failed to demonstrate the transmission of T. cruzi by soft ticks in laboratory settings, including O. moubata , O. talaje , and O. turicata . • Trypanosoma evansi Section title: Transmission of Trypanosoma following tick bites and feeding Educational score: 4.015711307525635 Domain: biomedical Document type: Study Language: en Investigations into the transmission of T . evansi by ticks began in the early 20th century. Some studies suggested that the soft tick Or . crossi , infected with T. evansi , could transmit the parasite to non-infected animals after a blood meal . However, in 1924, Yorke and Macfie did not confirm the transmission of this protozoan by O. crossi . Similarly, in 1976, Taylor-Lewis reported the unsuccessful transmission of T. evansi by H . dromedarii to rodents after blood feeding . More recently, Mahmoud et al. also failed to detect T. evansi DNA in uninfected rodents after blood feeding by infected O. savignyi . • Trypanosoma theileri and Trypanosoma theileri-like Section title: Transmission of Trypanosoma following tick bites and feeding Educational score: 2.4481513500213623 Domain: biomedical Document type: Study Language: en In 1981, a pioneering experimental study reported the inability of H . anatolicum carrying T . theileri to infect calves . However, this initial observation was challenged by subsequent studies conducted a few years later . Section title: Transmission of Leishmania following tick bites and feeding Educational score: 4.1182684898376465 Domain: biomedical Document type: Study Language: en To date, sandflies (Phlebotominae) are recognized as the primary biological vectors of Leishmania , though the potential role of ticks, fleas, and leeches as secondary vectors has been suggested . Five laboratory studies have attempted to investigate transmission after collecting ticks from vertebrates experimentally infected with Leishmania . All experiments were conducted on hard ticks (Ixodidae), with only ticks from the Rhipicephalus genus involved. Ticks were fed on either dogs or rodents, and two species were used: R . turanicus and R. sanguineus . R hipicephalus . sanguineus was the only species shown to be infected by Leishmania , specifically L. infantum and Leishmania sp . • Leishmania infantum Section title: Transmission of Leishmania following tick bites and feeding Educational score: 4.039830207824707 Domain: biomedical Document type: Study Language: en The transmission of L . infantum by ticks was first reported in 1930 by Blanc and Caminopétros, who infected squirrels after exposure to R . sanguineus ticks infected with what they referred to as ‘Leishmania kala azar,’ which most likely corresponds to parasites of the L. donovani complex today . However, this finding was not confirmed by later studies . In contrast, a report of successful transmission to 14 hamsters by R. sanguineus infected with L. infantum was documented , though this transmission method has not been further supported by subsequent research . Section title: Host infection following ingestion of infected ticks or injection with Trypanosoma -infected tick materials Educational score: 4.12646484375 Domain: biomedical Document type: Study Language: en Documented infection by trypanosomes following the ingestion of an infected invertebrate suggests that trypanosomes may also be transmitted through the ingestion of infected ticks . To date, nine studies on the Argasidae family and five on the Ixodidae family have investigated the transmission of trypanosomes in the laboratory, either through ingestion of infected ticks or by injection of infected material [ 41 , 42 , 45 , 47 , 48 , , , , , , 98 , 128 , 129 , 131 ]. Of these 14 studies, nine confirmed infections through the injection of infected tick material, while and only one confirmed infection through ingestion of infected ticks. However, drawing clear conclusions from these results remains challenging. Seven tick species were tested, O. moubata, O. crossi, O. venezuelensis, O. turicata, O. furcosus, R. pulchellu s, and H. a. anatolicum excavatum . Five Trypanosoma species were tested. • Trypanosoma cruzi Section title: Host infection following ingestion of infected ticks or injection with Trypanosoma -infected tick materials Educational score: 3.6223671436309814 Domain: biomedical Document type: Study Language: en Experimental transmission of T. cruzi through ingestion or injection of tick-infected material began in the 20th century. The injection of O. moubata -material infected with T. cruzi successfully caused rodent infection . Later studies confirmed rodent infection by T. cruzi -infected O. venezuelensis, O. turicata, O. furcosus, and O. moubata ticks . • Trypanosoma theileri and T. theileri-like Section title: Host infection following ingestion of infected ticks or injection with Trypanosoma -infected tick materials Educational score: 3.3504724502563477 Domain: biomedical Document type: Study Language: en Pioneering studies conducted in 1973 documented the inability to infect rodents by injecting T. theileri -infected hard tick material collected from cattle . In contrast to this observation, successful infections has been reported using O. moubata or H. a. anatolicum material infected with T. theileri . • Other Trypanosoma Section title: Host infection following ingestion of infected ticks or injection with Trypanosoma -infected tick materials Educational score: 3.866361141204834 Domain: biomedical Document type: Study Language: en As early as 1924, Yorke and Macfie attempted to transmit T. rhodesiense to rodents by injecting them with material from infected O. crossi ticks . In 1948, Packchanian was unsuccessful in infecting animals with T. brucei using similar protocol . Finally, in 1976, Taylor-Lewis also failed to infect rodents by injecting material from H. a. excavatum ticks infected with T. lewisi . Section title: Infection after ingestion or injection with Leishmania -infected ticks material Educational score: 4.126505374908447 Domain: biomedical Document type: Study Language: en Several studies have reported the presence of L. infantum in R. sanguineus and I. ricinus , as well as the transmission of other protozoa, such as Hepatozoon canis , to dogs after ingestion of ticks . Six studies have experimentally investigated the transmission of Leishmania via the oral route and the infective potential of injecting material from infected ticks [ , , , 61 , , , ]. Among these, five confirmed infections were documented in seven reports-four after injection and one after ingestion. All these studies focused exclusively on ticks from the Ixodidae family, specifically R. sanguineus , which were infected with various Leishmania species and fed on rodents or dogs. • Leishmania infantum and Leishmania chagasi ( Syn: L. infantum) Section title: Infection after ingestion or injection with Leishmania -infected ticks material Educational score: 3.205172300338745 Domain: biomedical Document type: Study Language: en Experimental infection of L. infantum by injecting infected R. sanguineus material was reported in 2010 . This finding was further supported by Coutinho and colleagues demonstrating infection with L. chagasi (syn: L. infantum) in rodent from infected dog ticks . • Leishmania Section title: Infection after ingestion or injection with Leishmania -infected ticks material Educational score: 3.9437057971954346 Domain: biomedical Document type: Study Language: en In 1984, a study assessed infection by injecting material from crushed, infected R. sanguineus ticks into two hunting dogs, crossbred between a German Shepherd and a Labrador Retriever. Following the injection, Leishmania species were detected in the recipient dogs using several diagnostic methods, suggesting the possibility of infection through the injection of tick-infected material . Section title: Transstadial transmission in ticks Educational score: 3.0862021446228027 Domain: biomedical Document type: Study Language: en The ability of a microorganism to survive the shedding process and persist for an extended period within the tick is crucial for successful transstadial transmission. For T . thylacis such transmission was documented in the tick I. tasmani , and then to the Australian short-nosed bandicoot ( Isoodon macrourus ) . Section title: Transstadial transmission of Trypanosoma Educational score: 3.0031754970550537 Domain: biomedical Document type: Study Language: en Transstadial passage of T . theileri in H . a. anatolicum ticks was reported in larvae and nymphs that fed on infected calves and tested positive after molting to the adult stage . This finding was corroborated in more recent studies . Section title: Transstadial transmission of Leishmania Educational score: 3.8434085845947266 Domain: biomedical Document type: Study Language: en Transstadial transmission of L . infantum in R . sanguineus has been documented since the 1930s . Recent studies have once again demonstrated the persistence of L. infantum kDNA in R. sanguineus nymphs and adults that fed on infected dogs before molting . However, the presence of live parasites could not be confirmed through microscopic examination or culture from the infected tick material . Section title: Transovarial passage of Trypanosoma Educational score: 4.204050064086914 Domain: biomedical Document type: Study Language: en The detection of flagellates and trypanosomes in tick ovaries was first reported in 1961 , leading to the proposal of transovarial transmission as a potential alternative route for maintaining the parasite in the wild. The earliest experimental reports of transovarial transmission of Trypanosoma in ticks date back to the early 1900s with T. cruzi , though further evidence was lacking for O . moubata or Rhipicephalus ticks . Transovarial transmission was also investigated for T. theileri in Hyalomma a. anatolicum , but no conclusive evidence was found . It wasn't until 2004 that a laboratory study demonstrated pathogenic trypanosomes being transmitted via tick ovaries . No conclusive evidence of transovarial transmission of T. evansi in R. sanguineus has been reported . Section title: Transovarial passage of Leishmania Educational score: 3.9149696826934814 Domain: biomedical Document type: Study Language: en Recent reports have confirmed the transovarial transmission of Leishmania in R . sanguineus , with the first evidence of this mode of transmission emerging in the early 1980s . Experimental studies have demonstrated the presence of L. infantum kDNA in R. sanguineus larvae four months after experimental infection of females . However, controversies still exist , and the only experiment conducted with L. major produced no conclusive evidence . Section title: Other circumstantial evidence Educational score: 4.092445373535156 Domain: biomedical Document type: Study Language: en Significant associations between tick infestation prevalence and the presence of anti- Leishmania antibodies in dogs from endemic areas of canine leishmaniasis have been reported [ 63 , 116 , , , ]. The prevalence of R . sanguineus infestation was significantly higher (p = 0.04) among seropositive dogs (38.5 %) compared to their seronegative counterparts (29.0 %). The probability of leishmania seropositivity was found to be 1.5 times higher in tick-infested dogs than in non-infested animals . Conversely, the odds of infection did not significantly differ between non-infested and R. sanguineus -infested dogs in one study . Section title: Other circumstantial evidence Educational score: 3.526998281478882 Domain: biomedical Document type: Study Language: en The near-perfect correlation between leishmania detection in dogs through fine-needle aspiration biopsy of the lymph nodes and the detection of leishmania in the tick's intestine via immunohistochemistry provides additional circumstantial evidence . Section title: Overview of the meta-analysis Educational score: 4.116222381591797 Domain: biomedical Document type: Study Language: en For the field studies, we identified 42 publications for meta-analysis and meta-regression . The use of a random-effects model was justified by the P and I 2 statistics, which showed significantly high heterogeneity . We identified publication bias in the selected studies based on visual inspection of the graph's asymmetry , which was confirmed by Egger's test ( Supplementary File , Table S1 ). The elimination, one by one or simultaneously, of the four publications showing bias did not affect the cumulative prevalence recorded. Fig. 3 Forest plot showing the prevalence of Trypanosomatidae detection in field-collected ticks. The horizontal lines represent the 95 % confidence intervals, while the diamond indicates the pooled effect size. Fig. 3 Fig. 4 Funnel plot with 95 % confidence intervals for assessing publication bias. Fig. 4 Section title: Overview of the meta-analysis Educational score: 3.992792844772339 Domain: biomedical Document type: Study Language: en The 42 studies selected included approximately 12,000 ticks collected worldwide. However, in some publications, it was not possible to determine the exact number of ticks used for the experiment. Therefore, the data we used for our analysis was the number of pools. Our results depicted an overall cumulative prevalence for Trypanosomatidae detection of 15.48 % (95 % CI: 7.99–24.61 %) . Section title: Overview of the meta-analysis Educational score: 4.226923942565918 Domain: biomedical Document type: Study Language: en We then examined factors associated with the detection of Leishmania and Trypanosoma having medical/veterinary interest in ticks. Factors examined included the sampling decade, study area (continent), animal host (family), tick genus or species, the detection method, parasite species, and location in the tick's organs ( Table 3 ). We recorded high heterogeneity in all subgroups; therefore, the pooled seroprevalence estimate for each subgroup was calculated using the random-effects model. Table 3 Pooled prevalence of parasite detection in ticks, categorized by sampling year, continent, host, tick genus/species, detection method, parasite genus/species, and localization. Table 3 Category Variable No. of studies No. of tested No. of positive % [95 % CI] Heterogeneity Univariate meta regression ꭕ2 P -value I 2 (%) P -value R 2 (%) I 2 -res (%) Sampling year 2000 or before 2 6470 19 0.22 [0.16–0.45] 1.14 <0.0001 12.0 0.000∗∗∗ 0.00 98.74 2001–2010 5 480 130 12.19 [0.87–32.08] 126.37 <0.0001 96.8 2011–2019 23 3043 518 21.13 [7.7–23.77] 818.31 <0.0001 97.3 2020 or after 12 1721 96 11.65 [0.3–30.84] 289.5 <0.0001 96.2 Continent Africa 4 4392 22 2.44 [0.00–9.54] 23.24 <0.0001 85.8 0.0056∗∗ 23.77 97.78 Asia 7 1165 44 3.11 [0.00–20.83] 131.61 <0.0001 95.4 Europe 10 3693 69 4.36 [1.49–9.06] 158.52 <0.0001 94.3 Island 1 478 2 0.42 [0.01–1.26] 0.000 <0.0001 – South America 20 1986 626 33.35 [14.27–37.83] 828.68 <0.0001 96.1 Host (Family) Several# 6 4894 43 2.83 [0.0–8.60] 80.46 <0.0001 93.8 0.0007∗∗ 0.00 98.34 Bovidae 6 1192 44 3.92 [1.20–7.85] 24.26 <0.0001 88.2 Canidae 20 2184 595 27.92 [14.51–43.57] 1071.56 <0.0001 98.2 Felidae 2 221 19 8.47 [5.07–12.60] 0.81 <0.0001 0.0 Other 7 722 57 21.23 [0.0–62.24]0 252.480 <0.0001 97.6 Tick Genus Amblyomma 10 328 27 8.78 [0–29.41] 100.12 <0.0001 91.0 0.0001∗∗∗ 2.20 97.09 Dermacentor 3 23 0 0.00 [0–5.25] 0.41 <0.0001 0.0 Haemaphysalis 4 360 00 0.00 1.58 <0.0001 0.0 Hyalomma 6 639 17 1.20 [0–14.55] 70.55 <0.0001 92.9 Ixodes 9 6906 42 1.91 [0–10.06] 71.41 <0.0001 88.8 Rhipicephalus 33 3271 668 19.06 [9.64–30.39] 1412.59 <0.0001 97.7 Tick species A. cajennense 1 131 0 0.00 [0–7.04] 3.86 <0.0001 0.0001∗∗∗ 3.29 97.50 A. ovale 1 10 0 0.00 [0–16.52] 0.00 <0.0001 – A. sabanerae 1 10 9 90.00 [61.91–100] 0.00 <0.0001 0.0 A. tigrinum 2 28 0 24.86 [0–95.91] 16.89 <0.0001 – A. variegatum 2 165 11 3.09 [0–24.26] 0.43 <0.0001 94.1 Amblyomma spp. 2 43 4 0.00 [0–0.64] 11.54 <0.0001 91.30.0 D. marginatus 3 21 0 0.00 [0–5.25] 0.59 <0.0001 0.0 H. aegyptium 2 32 12 32.69 [11.66–56.75] 0.46 <0.0001 0.0 H. detritum 1 1 1 100 [0–100] 0.00 <0.0001 – H. dromedarii 2 45 5 16.56 [0–88.80] 17.10 <0.0001 94.2 H. excavatum 3 291 0 0.00 1.45 <0.0001 0.0 H. lusitanicum 1 3 0 0 [0–50] 0.00 <0.0001 – H. marginatum 4 171 0 0.00 2.04 <0.0001 0.0 Hyalomma sp. 2 81 0 0.00 [0–2.36] 0.01 <0.0001 0.0 Ha. longicornis 1 308 0 0.00 [0–0.58] 0.00 <0.0001 – Ha. parva 1 41 0 0.00 [0–4.15] 0.00 <0.0001 – Ha. punctata 1 6 0 0.00 [0–26.80] 0.00 <0.0001 – Ha. sulcata 2 4 0 0.00 [0–78.74] 0.07 <0.0001 0.0 Haemaphysalis. sp. 1 13 0 0.00 [0–12.82] 0.00 <0.0001 – I. ricinus 8 6580 32 1.36 [0–10.39] 64.66 <0.0001 87.6 I. ventalloi 1 62 3 6.45 [1.42–14.19] 0.00 <0.0001 – Ixodes sp. 1 5 0 0.00 [0–31.73] 0.00 <0.0001 – R. (Boophilus) 6 1025 62 0.00 [0–3.92] 0.51 <0.0001 0.0 R. bursa 3 23 0 13.54 [0–47.12] 185.13 <0.0001 22.2 R. pusillus 2 18 3 17.65 [2.57–39.97] 0.02 <0.0001 0.0 R. sanguineus 21 2222 583 25.15 [11.67–41.19] 1092.57 <0.0001 97.9 R. turanicus 4 158 10 2.48 [0–1467] 23.70 <0.0001 87.3 Rhipicephalus sp. 1 43 3 6.98 [0.9–16.93] 0.00 <0.0001 – Detection method Microscopy 3 6533 20 0.1 [0.0–0.23] 3.47 <0.0001 42.4 0.000∗∗∗ 5.37 98.84 Molecular 39 5181 743 17.55 [9.31–27.44] 1937.17 <0.0001 98.1 Parasite genus Leishmania 30 4569 719 18.87 [9.12–30.75] 1642.76 <0.0001 98.294.6 0.0046∗∗ 7.10 98.88 Trypanosoma 12 7739 93 4.62 [1.14–9.79] 203.03 <0.0001 Parasite species L. braziliensis 1 75 32 42.67 [31.64–64.66] 0.00 <0.0001 – 0.000∗∗∗ 9.25 98.97 L. chagas ( syn L. infantum) 1 444 107 24.10 [20.23–28.19] 0.00 <0.0001 – L. guyanensis 1 81 3 12.12 [2.79–25.84] 0.00 <0.0001 – L. infantum 18 2124 323 15.44 [7.18–25.89] 679.35 <0.0001 97.5 L. major 1 1 1 100 [0–100] 0.08 <0.0001 – L. martiniquensis 1 578 2 0.35 [0–1.04] 0.00 <0.0001 – Leishmania sp. 6 683 194 51.82 [8.42–93.57] 0.00 <0.0001 94.4 T. caninum 1 9 1 11.11 [0–41.77] 0.00 <0.0001 – T. congolense 1 33 4 3.70 [0.47–9.18] 0.00 <0.0001 – T. cruzi 3 583 8 2.39 [0–10.25] 895.52 <0.0001 91.2 T. evansi 4 892 38 6.44 [0–23.33] 13.00 <0.0001 95.9 T. theileri 2 6220 14 0.20 [0.12–0.36] 73.71 <0.0001 0.0 T. vivax 3 441 42 10.88 [2.91–22.73] 22.82 <0.0001 84.6 Localization in ticks H 2 6470 19 0.29 [0.16–0.45] 1.14 <0.0001 12.0 0.000∗∗∗ 0.00 98.89 G 3 209 164 74.32 [28.48–99.99] 312.09 <0.0001 97.3 GR 35 4532 478 13.45 [6.62–21.87] 1234.08 <0.0001 97.2 GR-SG 1 95 11 11.58 [5.82–18.88] 0.00 <0.0001 – H-GR 1 444 107 24.10 [20.23–28.19] 0.00 <0.0001 – SG 2 110 35 31.79 [23.31–40.91] 0.00 <0.0001 0.0 O 2 165 74 44.48 [37.27–52.53] 0.67 <0.0001 0.0 G: gut ; Gr: whole body ; H: hemolymph ; O: ovaries ; SG: salivary glands ∗0.05; ∗∗0.01; ∗∗∗0.001, # In these studies, various tick species were allowed to feed on diverse infected host (Swiss mice, Meadow voles, Rats, Mice, Rabbits, Camel, Dog, Guinea pig or White rat). In these papers, it was not possible to retrieve the information on the host origin of the ticks tested. Section title: Detection method Educational score: 4.081073760986328 Domain: biomedical Document type: Study Language: en Molecular biology yielded the highest detection rates, reaching 17.55 % (with a confidence interval of 9.31–27.44 %), surpassing the rates detected by microscopic methods, which stand at a mere 0.1 % (confidence interval: 0–0.23 %). Despite the specificity of microscopy in identifying Trypanosomatidae they demand skilled personnel for accurate parasite detection. The efficacy of these methods varies with the type of sample and generally falls short of the sensitivity and specificity offered by PCR and cell culture methods . Due to their superior sensitivity and specificity, molecular techniques are regarded as more effective . Section title: Temporal analysis Educational score: 3.6565113067626953 Domain: biomedical Document type: Study Language: en There were statistically significant differences across the collection decade ( Table 3 ). The highest annual prevalence recorded was 14.92 % between 2011 and 2019, and the lowest at 0.29 % was reported before the 2000s. This increasing prevalence trend since 2000 is likely due to advances in the performance of molecular detection methods and/or the impacts of climate change on vector populations and behaviors . Section title: Tick's geographical origin and host genus Educational score: 3.261178493499756 Domain: biomedical Document type: Study Language: en We also assessed differences according to geographical origin (continent) ( Table 3 ). The highest prevalence, 25.17 % was recorded in South America, while the lowest was in Africa . The cumulative prevalence statistics by host animal on which ticks were collected, displayed a significant difference between animal hosts, with the highest cumulative prevalence being on Canidae . Section title: Tick's genus Educational score: 4.099339485168457 Domain: biomedical Document type: Study Language: en The prevalence of tick infection significantly varies according to the tick's taxonomic status , from 19.06 % in Rhipicephalu s to 8.78 % (95 % CI: 0–29.41 %, 27/328) in Amblyomma or 1.91 % and 1.20 % in Ixodes and Hyalomma , respectively, to 0.0 % in Dermacentor and Haemaphysalis ( Table 3 ). Section title: Detection method, genus and tick's organs Educational score: 4.113786697387695 Domain: biomedical Document type: Study Language: en We recorded statistical differences according to the detection method (p > 0.05). The prevalence was higher at 17.55 % (95 % CI: 9.31, 27.44) with molecular methods and lowest at 0.1 % (95 % CI: 0–0.23) using microscopy. Moreover, the infection rate was significantly higher at 18.87 % [9.12–30.75] for Leishmania than for Trypanosoma at 4.62 % [1.14–9.79]. Infection rate also varied significantly (p = 0.000) by organ in ticks: the highest rate is 74.32 % (95 % CI: 28.24–99.99, 164/209) in the digestive tract, followed by 44.48 % [37.27–52.53] in the ovaries, 31.79 % [23.31–40.91 %] in the salivary glands, and the lowest rate of infection is 0.29 % [95 % CI: 0.16–0.45 %] in the hemolymph ( Table 3 ). Section title: Experimental studies Educational score: 3.851524829864502 Domain: biomedical Document type: Study Language: en For the experimental studies, 37 publications were selected. Data were extracted from these research papers. Quantitative data such, as the number of ticks used for experimental infections, were not considered in the meta-analysis. They were transformed into semi-quantitative ones (presence or absence of parasites following experimental infection or transmission). Since no heterogeneity was detected in the data set, the common-effect model was chosen for the meta-analysis. Section title: Ingestion after blood feeding on an infected host Educational score: 4.243812084197998 Domain: biomedical Document type: Study Language: en The meta-analysis was performed on 36 studies. The analysis showed the presence of parasites in ticks after their blood meal in 91 % [72–100 %] of studies . The factors associated with the detection of Leishmania and Trypanosoma in the blood meal were analyzed taking into account each actor involved in the transmission cycle, tick, animal host and parasite ( Table 4 ). No heterogeneity was detected in these subgroups. Rate estimates pooled for each subgroup were calculated using a common-effects model. • Tick's family and genus Table 4 Pooled rate of parasite detection in ticks from experimental transmission studies. Table 4 Acquisition of pathogens via tick blood feeding Category Variable No. of studies No. of positive % [95 % CI] Heterogeneity Univariate meta regression ꭕ2 P -value I 2 (%) P -value R 2 (%) I 2 -res (%) Ticks Family Argasidae 16 16 100 [81.65–100] 0.00 0.9966 0.0 0.0976 0.00 0.00 Ixodidae 21 15 78.01 [48.91–98.34] 15.86 0.9966 0.0 Ticks Genus Amblyoma 1 1 100 [0–100] 0.00 0.9938 – 0.3905 0.00 0.00 Hyalomma 4 3 82.18 [16.67–100] 2.78 0.9938 0.0 Ornithodoros 15 15 100 [80.68–100] 0.00 0.9938 0.0 Rhipicephalus 16 11 74.57 [40.89–98.60] 12.72 0.9938 0.0 Ticks species A. americanum 1 1 100 [0–100] 0.00 0.9989 – 0.6118 0.00 0.00 B. decoloratus 1 1 100 [0–100] 0.00 0.9989 – D. andersoni 2 2 100 [21.62–100] 0.00 0.9989 0.0 H. a . anatolicum 3 2 72.14 [2.45–100] 2.47 0.9989 18.9 H. a . excavatum 1 1 100 [0–100] 0.00 0.9989 – H. dromaderii 1 1 100 [0–100] 0.00 0.9989 – H. impressum 1 1 100 [0–100] 0.00 0.9989 – O. amblus 1 1 100 [0–100] 0.00 0.9989 – O. crossi 4 4 100 [48.72–100] 0.00 0.9989 0.0 O. furcosis 1 1 100 [0–100] 0.00 0.9989 – O. hermsi 2 0 0 [0–78.74] 0.00 0.9989 0.0 O. lahorensis 2 2 100 [21.26–100] 0.00 0.9989 0.0 O. moubata 7 7 100 [65.46–100] 0.00 0.9989 0.0 O. parkeri 1 1 100 [0–100] 0.00 0.9989 – O. savignyi 1 1 100 [0–100] 0.00 0.9989 – O. talaje 1 0 0 [0–100] 0.00 0.9989 – O. turanicus 2 2 100 [21.62–100] 0.00 0.9989 0.0 O. venzualensis 1 1 100 [0–100] 0.00 0.9989 – R. sanguneus 13 11 91.99 [58.62–100] 6.26 0.9989 0.0 R. sanguneus s. l . 2 0 0 [0–78.74] 0.00 0.9989 0.0 R. pulchellus 1 1 100 [0–100] 0.00 0.9989 – Parasite genus Leishmania 14 9 69.10 [62.64–97.17] 11.90 0.9974 0.0 0.0794 0.00 0.00 Trypanosoma 22 21 99.11 [80.73–100] 3.53 0.9974 0.0 Parasite Species L. donovani 1 1 100 [0–100] 0.00 0.9928 – 0.7192 0.00 0.00 L. chagasi (syn L.infantum) 2 2 100 [21.26–100] 0.00 0.9928 0.0 L. infantum 5 4 87.58 [29.26–100] 2.96 0.9928 0.0 L. kala azar £ 4 1 17.82 [0–83.24] 2.78 0.9928 0.0 L. major 1 1 100 [0–100] 0.00 0.9928 – Leishmania sp. 1 1 100 [0–100] 0.00 0.9928 – T. bruci 1 1 100 [0–100] 0.00 0.9928 – T. cruzi 8 8 100 [68.71–100] 0.00 0.9928 0.0 T. evansi 7 6 92.94 [46.20–100] 3.17 0.9928 0.0 T. gambiense 1 1 100 [0–100] 0.00 0.9928 – T. lewisi 2 2 100 [21.26–100] 0.00 0.9928 0.0 T. rhodesciense 2 2 100 [21.26–100] 0.00 0.9928 0.0 T. theileri 4 3 82.18 [16.67–100] 2.78 0.9928 0.0 T. theileri like 1 1 100 [0–100] 0.00 0.9928 – Donor host family Bovidae 4 3 82.18 [16.67–100] 2.78 0.9471 0.0 0.9455 0.00 0.00 Canidae 13 9 75.34 [37.81–99.71] 10.25 0.9471 0.0 Camelidae 2 2 100 [21.26–100] 0.00 0.9471 0.0 Rodentia 15 14 93.73 [63.97–100] 42.76 0.9471 0.0 ND 2 2 100 [21.26–100] 0.00 0.9471 0.0 Other 1 1 100 [0–100] 0.00 0.9471 – Ticks 1 1 100 [0–100] 0.00 0.9471 – Infection via the injection of ticks infected material Ticks Family Argasidae 9 7 85.25 [41.62–100] 5.76 0.6062 0.0 0.2884 0.00 0.00 Ixodidae 13 7 55.23 [18.49–89.66] 11.96 0.6062 0.0 Ticks Genus Hyalomma 4 2 50.0 [0–100] 3.70 0.5378 18.9 0.5954 0.00 0.00 Ornithodoros 9 8 85.25 [41.62–100] 5.76 0.5378 0.0 Rhipicephalus 7 4 59.68 [11.06–99.18] 6.34 0.5378 5.4 Ticks species B. decoloratus 1 0 0 [0–100] 0.00 0.8803 – 0.2229 0.00 0.00 D. andersoni 2 0 0 [0–78.74] 0.00 0.8803 0.0 H. a. anatolicum 3 2 72.14 [2.45–100 2.47 0.8803 18.9 H. a. excavatum 1 0 0 [0–100] 0.00 0.8803 – H. dromaderii 1 0 0 [0–100] 0.00 0.8803 – H. impressum 1 0 0 [0–100] 0.00 0.8803 – O. amblus 1 1 100 [0–100] 0.00 0.8803 – O. crossi 1 0 0 [0–100] 0.00 0.8803 – O. furcosus 1 1 100 [0–100] 0.00 0.8803 – O. hermsi 2 0 0 [0–78.74] 0.00 0.8803 0.0 O. moubata 4 4 100 [48.72–100] 0.00 0.8803 0.0 O. perkeri 1 1 100 [0–100] 0.00 0.8803 – O. talaje 1 0 0 [0–100] 0.00 0.8803 – O. turanicus 1 0 0 [0–100] 0.00 0.8803 – O. turicata 2 1 50.0 [0–100] 1.85 0.8803 46.0 O. venzualensis 1 1 100 [0–100] 0.00 0.8803 – R. pulchellus 1 0 0 [0–100] 0.00 0.8803 – R. sanguineus 6 5 90.82 [38.83–100] 3.08 0.8803 0.0 R. sanguineus s.I. 1 0 0 [0–100] 0.00 0.8803 – Parasite genus Leishmania 7 5 78.10 [27.34–100] 5.29 0.5774 0.0 0.7666 0.00 0.00 Trypanosoma 14 9 69.10 [32.64–97.17] 11.9 0.5774 0.0 Donor host Family Bovidae 4 2 50.0 [0–100] 3.70 0.5180 18.9 0.7557 0.00 0.00 Camelidae 1 1 100 [0–100] 0.00 0.5180 – Canidae 5 4 87.58 [29.26–100] 2.96 0.5180 0.0 Rodentia 11 8 68.26 [27.33–98.66] 9.42 0.5180 0.0 Receiver host Family Bovidae 3 2 72.14 [2.45–100] 2.47 0.5387 18.9 0.5494 0.00 0.00 Canidae 1 1 100 [0–100] 0.00 0.5387 – Other 1 0 0 [0–100] 0.00 0.5387 – Rodentia 15 11 63.49 [28.31–93.43] 13.32 0.5387 0.0 Ticks 2 2 100 [21.26–100] 0.00 0.5387 0.0 Parasite species L. chagasi (Syn L. infantum) 1 1 100 [0–100] 0.00 0.8397 – 0.2614 0.00 0.00 L. infantum 1 1 100 [0–100] 0.00 0.8397 – L. kala azar £ 4 2 50.0 [0–100] 3.70 0.8397 18.9 Leishmania sp. 1 1 100 [0–100] 0.00 0.8397 – T. brucei 1 0 0 [0–100] 0.00 0.8397 – T. cruzi 6 6 100 [61.37–100] 0.00 0.8397 0.0 T. evansi 1 0 0 [0–100] 0.00 0.8397 – T. lewisi 1 0 0 [0–100] 0.00 0.8397 – T. rhodeseinse 1 0 0 [0–100] 0.00 0.8397 – T. theileri 4 3 82.18 [16.76–100] 2.78 0.8397 0.0 T. theileri like 1 0 0 [0–100] 0.00 0.8397 – Transmission through blood feeding Ticks Family Argasidae 10 3 23.71 [0–66.41] 7.77 0.5314 0.9 0.4962 0.00 0.00 Ixodidae 11 5 34.33 [0.0–94] 10.09 0.5314 0.0 Ticks Genus Hyalomma 4 2 50.0 [0–100] 3.70 0.4677 18.9 0.7745 0.00 0.00 Ornithodoros 10 3 23.71 [0–66.41] 7.77 0.4677 0.0 Rhipicephalus 7 3 40.32 [0.48–88.94] 6.32 0.4677 5.4 Parasite genus Leishmania 5 2 36.51 [0–92.81] 4.44 0.9952 9.9 0.5011 0.00 0.00 Trypanosoma 16 8 33.22 [5.25–67.40] 13.88 0.9952 0.0 Donnor host family Bovidae 4 2 50.0 [0–100] 3.70 0.9017 18.9 0.0405∗ 0.00 0.00 Camelidae 2 2 100 [21.26–100] 0.00 0.9017 0.0 Canidae 7 4 59.68 [11.06–99.18] 6.34 0.9017 5.4 Rodentia 8 0 0 [0–31.29] 0.00 0.9017 0.0 Receiver host family Bovidae 3 2 72.14 [2.45–100] 2.47 0.8461 18.9 0.0678 0.00 0.00 Canidae 3 2 72.14 [2.45–100] 2.47 0.8461 18.9 Other 2 2 100 [21.26–100] 0.00 0.8461 0.0 Rodentia 13 4 8.01 [0–41.38] 6.26 0.8461 0.0 Ticks species B. decoloratus 1 0 0 [0–100] 0.00 0.6280 – 0.6077 0.00 0.00 D. andersoni 1 0 0 [0–100] 0.00 0.6280 – H. a. anatolicum 3 2 72.14 [2.45–100] 2.47 0.6280 18.9 H. a. excavatum 1 0 0 [0–100] 0.00 0.6280 – H. dromaderii 1 0 0 [0–100] 0.00 0.6280 – H. impressum 1 0 0 [0–100] 0.00 0.6280 – O. crossi 4 3 82.18 [16.67–100] 2.78 0.6280 0.0 O. hermsi 1 0 0 [0–100] 0.00 0.6280 – O. lahorensis 2 2 100 [21.26–100] 0.00 0.6280 0.0 O. moubata 3 0 0 [0–61.92] 0.00 0.6280 0.0 O. savigny 1 0 0 [0–100] 0.00 0.6280 – O. talaje 1 0 0 [0–100] 0.00 0.6280 – O. turanicus 1 0 0 [0–100] 0.00 0.6280 – O. turicata 1 0 0 [0–100] 0.00 0.6280 – O. venzualensis 1 0 0 [0–100] 0.00 0.6280 – R. pulchellus 1 0 0 [0–100] 0.00 0.6280 – R. sanguineus 6 3 50.0 [2.78–97.22] 5.55 0.6280 9.9 Parasite species L. infantum 2 1 50.0 [0–100] 1.85 0.5302 46.0 0.5529 0.00 0.00 L. kala azar £ 2 0 0 [0–78.74] 0.00 0.5302 0.0 Leishmania sp. 1 1 100 [0–100] 0.00 0.5302 – T. cruzi 6 1 9.18 [0–61.17] 3.08 0.5302 0.0 T. evansi 6 3 50.0 [2.78–97.22] 5.55 0.5302 9.9 T. lewisi 1 0 0 [0–100] 0.00 0.5302 – T. theileri 3 1 27.86 [0–97.55] 2.47 0.5302 18.9 T. theileri like 1 1 100 [0–100] 0.00 0.5302 – Vertical transmission Ticks Family Argasidae 1 0 0 [0–100] 0.00 0.4606 – 0.2809 0.00 0.00 Ixodidae 12 7 61.27 [22.41–94.58] 10; 79 0.4606 0.0 Ticks Genus Hyalomma 2 1 50.0 [0–100] 1.85 0.3787 46.0 0.5422 0.00 0.00 Ornithodoros 1 0 0 [0–100] 0.00 0.3787 – Rhipicephalus 10 6 63.49 [21.05–97.58] 8.88 0.3787 0.0 Ticks species H. a. anatolicum 2 1 50.0 [0–100] 1.85 0.4143 46.0 0.4394 0.00 0.00 O. moubata 1 0 0 [0–100] 0.00 0.4143 – R. pulchellus 1 0 0 [0–100] 0.00 0.4143 – R. sanguineus 9 7 72.14 [27.07–100] 7.40 0.4143 0.0 Parasite genus Leishmania 8 7 82.18 [35.16–100] 5.55 0.6668 0.0 0.0634 0.00 0.00 Trypanosoma 5 1 12.42 [0–70.74] 2.96 0.6668 0.0 Donor host family Bovidae 3 1 27.86 [0–97.55] 2.47 0.8446 18.9 0.0425∗ 0.00 0.00 Canidae 7 6 92.94 [46.20–100] 3.17 0.8446 0.0 Rodentia 3 0 0 [0–61.92] 0.00 0.8446 0.0 Receiver host family Bovidae 2 1 50.0 [0–100] 1.85 0.4748 46.0 0.3582 0.00 0.00 Canidae 1 1 100 [0–100] 0.00 0.4748 – ND 4 3 82.18 [16.67–100] 2.78 0.4748 0.0 Rodentia 5 1 12.42 [0–70.74] 2.69 0.4748 0.0 Ticks 1 1 100 [0–100] 0.00 0.4748 – Parasite species L. chagasi ( Syn L. infantum) 2 1 50.0 [0–100] 1.85 0.5046 46.0 0.3655 0.00 0.00 L. infantum 3 3 100 [38.08–100] 0.00 0.5046 0.0 L. major 1 0 0 [0–100] 0.00 0.5046 – L. kala azar £ 1 1 100 [0–100] 0.00 0.5046 – Leishmania sp. 1 1 100 [0–100] 0.00 0.5046 – T. cruzi 1 0 0 [0–100] 0.00 0.5046 – T. evansi 1 0 0 [0–100] 0.00 0.5046 – T.theileri 3 1 27.86 [0–97.55] 2.47 0.5046 18.9 ∗0.05; ∗∗0.01; ∗∗∗0.001 £ L. kala azar refers to members of the L. donovani complex ( L. infantum and L. donovani ) without any other information on parasite typing at the time of the study. We therefore use the term proposed by the author. # ticks (receiver host) were infected via the inoculation of A. americanum -infected hemolymph (donor host). Section title: Ingestion after blood feeding on an infected host Educational score: 4.10072135925293 Domain: biomedical Document type: Study Language: en For tick families, positivity rates were 100 % (95 % CI: 81.65–100) for Argasidae and 78.01 (95 % CI: 48.9–98.84 %) for Ixodidae, with no statistical difference according to tick family (p > 0.05). Slight variations were recorded for the genus, with no statistically significant difference. For the genera Ornithodoros and Amblyomma , all publications reported positive detection after the blood meal; for the genera Rhipicephalus and Hyalomma , detection rates were 74.57 % and 82.18 %, respectively. A large variation in prevalence is recorded at the species level, related to the low number of studies published ( Table 4 ). • Parasite genus Section title: Ingestion after blood feeding on an infected host Educational score: 3.784996747970581 Domain: biomedical Document type: Study Language: en The highest detection rate was 99.11 % (95 % CI: 80.73–100) for Trypanosoma , whereas Leishmania was detected in 69.10 % (95 % CI: 62.64–97.17) of the studies. However, this difference is not statistically significant (P > 0.05) ( Table 4 ). • Host family Section title: Ingestion after blood feeding on an infected host Educational score: 1.9722965955734253 Domain: biomedical Document type: Study Language: en No statistical differences were recorded ( Table 4 ). Section title: Infection by injection of tick-infected material Educational score: 2.5436642169952393 Domain: biomedical Document type: Study Language: en The meta-analysis includes 22 scientific papers. The common-effects model was used to analyze associated factors. About 72 % (95 % CI: 42–95 %) of articles show positive infection results. . • Tick's family, genus and species Section title: Infection by injection of tick-infected material Educational score: 3.9037697315216064 Domain: biomedical Document type: Study Language: en The infection rate elicited via the injection of Argasidae-infected material was statistically higher than of Ixodidae-infected ones (rate of 85.25 % vs. 55.23 %). The highest rate, 85.25 %, was recorded for Ornithodoros , followed by Rhipicephalus and Hyalomma . However, if all these observations were not statistically significant, they interestingly point to some specificity according to the tick genus ( Table 4 ). • Parasite's genus and species Section title: Infection by injection of tick-infected material Educational score: 2.7007858753204346 Domain: biomedical Document type: Study Language: en No significant difference was recorded (p > 0.05). Although we observed a generally higher infection rate with T. cruzi , T. theileri, Leishmania . sp., L. chagasi (Syn L. infantum ), and L. infantum infected tick material. • Host family Section title: Infection by injection of tick-infected material Educational score: 3.5881903171539307 Domain: biomedical Document type: Study Language: en These analyses disclosed that tick material collected from infected Camelidae was more likely to initiate infection when injected into a noninfected recipient and Canidae appears to be more susceptible to infection when injected with infected tick material. Section title: Transmission through tick's blood feeding on a non-infected host Educational score: 4.102976322174072 Domain: biomedical Document type: Study Language: en Tick-borne pathogen transmission can occur via mechanical or biological means. In mechanical transmission, ticks act as carriers, transferring pathogens between hosts without mandatory pathogen development within the tick. In contrast, biological transmission involves the pathogen undergoing necessary biological changes or replication within the tick, completing part of its life cycle before infecting the next host. We performed a meta-analysis on data extracted from 21 publications dealing with experimental transmission by ticks via blood feeding ( Table 4 ). This analysis showed 34 % (95 % CI: 8–64 %) of studies confirming transmission . The common-effects model was used to analyze associated factors. • Tick's family Section title: Transmission through tick's blood feeding on a non-infected host Educational score: 4.0864129066467285 Domain: biomedical Document type: Study Language: en The Ixodidae appeared to be more able to transmit Trypanosomatidae of medical or veterinary interest than Argasidae, with rates of 34.33 % (95 % CI: 0–94 %) and 23.7 % (95 % CI: 0–66.4 %), respectively ( Table 4 ). Regarding the genus, minor variations were recorded without significant differences (p > 0.05). Regarding tick species, R. sanguineus , O. lahorensis , O. crossi , and H. a. anatolicum seemed more able to transmit Trypanosomatidae parasites of medical and veterinary interest. However, the sample size is too small to get insight into the statistical significance of these observations. • Parasite genus Section title: Transmission through tick's blood feeding on a non-infected host Educational score: 3.809497117996216 Domain: biomedical Document type: Study Language: en Although the success of transmission attempts is higher with Leishmania (82.18 % CI:35.16–100 %) than with Trypanosoma (12.42 % CI: 0–70.74 %), the meta-analysis does not record a statistically significant difference (p > 0.05) ( Table 4 ). • Donor and receiver host family Section title: Transmission through tick's blood feeding on a non-infected host Educational score: 4.1158447265625 Domain: biomedical Document type: Study Language: en Surprisingly, the donor host appears to be a factor influencing the subsequent transmission of the pathogen during tick blood feeding (p < 0.05) Table 4 . The infection rate for ticks varied from 100 % to 95 % (CI: 21.26–100 %) in Camelidae, to 59.68 % for Canidae and 50.0 % for Bovidae. The eight studies focusing on ticks collected on infected rodents reported no transmission. The host recipient also showed heterogeneity, with Canidae and Bovidae being more frequently infected at a rate of 72.14 % [2.45–100 %] than rodents (8.01 %, [0–41.38 %]). Section title: Vertical transmission Educational score: 4.175984859466553 Domain: biomedical Document type: Study Language: en Our analysis includes only 13 studies focusing on the vertical transmission of Trypanosomatidae of medical or veterinary interest by ticks, with 55 % supporting the vertical transmission, as detailed in the supplementary file . The factors associated with this transmission were evaluated using the common-effect model. Despite the small sample size, vertical transmission is recorded at 61.27 % [22.41–94.58] for ticks of the Ixodidae family and 0 % for the Argasidae, although only one study deals with this issue. No significant difference exists according to genus and species ( Table 4 ). Concerning genus and parasite species, parasites belonging to the Leishmania genus were better adapted to vertical transmission (82.18 [35.16–100]) than those of the Trypanosoma genus (12.42 [0–70.74]). Parasites from the L. donovani complex ( L. donovani or L. infantum ) appear to be adapted to vertical transmission. Also, the host family from which ticks feed plays a significant role in variability . Ticks feeding on dogs (Canidae) have the highest vertical transmission rate at 92.94 % [46.20–100 %], followed by those feeding on Bovidae at 27.86 % [0–97.55], and lastly, rodents with no vertical transmission of Trypanosomatidae in ticks following blood meal on rodent infected host. Section title: Discussion Educational score: 3.9838130474090576 Domain: biomedical Document type: Study Language: en Biologists have shown particular interest in insects that serve as vectors for Trypanosomatidae due to the significant impact these parasites have on various animal species, including humans . While nearly all Trypanosomatidae are transmitted by insects, a single publication documented an avian trypanosome transmitted by a non-traditional vector: an arachnid from the subclass Acari . This anomaly spurred further investigations into the presence of Trypanosomatids within ticks . Consequently, there has been an increased focus on understanding the potential role of ticks in harboring and transmitting these pathogenic protozoans. Section title: Discussion Educational score: 4.202681541442871 Domain: biomedical Document type: Study Language: en To determine the prevalence of Trypanosomatidae of medical and veterinary interest in wild-caught ticks from endemic areas, both molecular (PCR, qPCR, PCR-HRM) and parasitological/immunological (microscopic examination, IHC) methods were employed. Molecular techniques that amplify genomic DNA, which can persist after parasite death, are more sensitive than parasitological/immunological methods that target living parasites or their immunological determinants, which degrade rapidly upon the death of the parasite. Statistical differences in detection rates were observed depending on the method used. Specifically, the highest prevalence (17.55 %) was recorded using molecular methods, compared to only 0.1 % for microscopic detection of parasites. The presence of DNA or parasites in the digestive systems of blood-fed ticks collected from hosts has limited predictive value for inferring a vectorial role. Most publications included in our systematic review and meta-analysis focused on ticks collected directly from hosts, concentrating on detecting pathogens from host blood deposited in tick bodies. DNA detection alone is insufficient, particularly in the case of ticks, due to their digestive capabilities and other metabolic peculiarities. To further analyze the prevalence of Trypanosomatidae in field-collected tick samples, it will be necessary to isolate the parasites themselves from these ticks and/or detect parasite-specific mRNA, which serves as a better indicator of parasite survival in the digestive tract and other tick organs. Section title: Discussion Educational score: 4.22392463684082 Domain: biomedical Document type: Study Language: en Data on field tick infections reveal that the detection of Trypanosomatidae of medical or veterinary interest in ticks varies significantly, ranging from 0.01 % to 1.26 % in some regions to as high as 14.27 %–37.83 % in others, depending on the country or continent ( Table 3 ). Many studies utilize pooled samples to ascertain prevalence, which can greatly overestimate the results. Nonetheless, the meta-analysis provides initial evidence of a high frequency of contact between infected hosts and ticks, a crucial factor for facilitating transmission by arthropod vectors. Unfortunately, in many regions where Trypanosomatidae infections are common, there is a lack of available information regarding the infection rates of these pathogenic agents in their proven vectors and/or in ticks. For instance, while the Mediterranean area has a high incidence of leishmaniases , there is no data on the carriage of Leishmania by ticks in countries such as Egypt, Libya, and Morocco. Similarly, Latin America and the Caribbean are affected by Chagas disease, caused by T. cruzi , yet no information on its presence in ticks is available. This lack of data complicates efforts to conduct a global analysis of the seasonal activity patterns of ticks in relation to the incidence of Trypanosomatidae pathogen infections in hosts, as well as the geographical overlap between tick populations and human or animal infections caused by Trypanosomatidae pathogens. Section title: Discussion Educational score: 3.990574598312378 Domain: biomedical Document type: Review Language: en If 996 species of ticks (774 hard ticks and 221 soft ticks) are described worldwide , with 25 species acting as vectors of major diseases, the presence of Trypanosomatidae pathogens of medical or veterinary interest has been investigated in twenty tick species. In South America, 137 species of hard ticks from five genera and 87 species of soft ticks have been reported . All studies collected for this review focused on the Ixodidae family, with no field data available on soft ticks from the Argasidae family. The detection rate among members of the Rhipicephalus genus is the highest at 17.49 %, followed by Amblyomma (11.47 %), Hyalomma (2.68 %), and Ixodes (1.87 %), while Dermacentor and Haemaphysalis ticks were negative. Section title: Discussion Educational score: 4.162599563598633 Domain: biomedical Document type: Study Language: en Variability in field studies regarding the detection of Trypanosomatidae in ticks can often be attributed to host effects. Specifically, ticks harvested from Canidae—predominantly non-questing ticks belonging to the Rhipicephalus genus—exhibit a higher detection rate of pathogens compared to ticks collected from other mammals . This discrepancy may partly result from the close relationship between dogs and humans, coupled with dogs' heightened susceptibility to T. cruzi , which could increase the risk of tick infection . Additionally, dogs serve as significant reservoirs for several Leishmania species, including L. infantum , L. peruviana , and L. donovani . Section title: Discussion Educational score: 4.143670082092285 Domain: biomedical Document type: Study Language: en The extensive geographical distribution of ticks belonging to the genus Rhipicephalus , their wide range of animal hosts, known vector competence, and diverse morphology provide strong arguments for this meta-analysis on their potential role in the transmission of Trypanosomatidae . R hipicephalus sanguineus is a representative species of this genus, particularly due to its close association with domestic dogs, which are known reservoirs for Leishmania . This connection highlights the likely involvement of this tick species in the persistence and transmission of these parasites in natural habitats . Section title: Discussion Educational score: 3.9701335430145264 Domain: biomedical Document type: Other Language: en The concept of vector competence refers to the innate ability of an arthropod to harbor and transmit microbial agents . Establishing the vector capacity of a tick involves confirming its ability to become infected during a blood meal on a host, facilitating the multiplication of the pathogen prior to transmission through saliva, and maintaining the pathogen throughout the tick's developmental stages for potential vertical transmission . Section title: Discussion Educational score: 4.174416542053223 Domain: biomedical Document type: Study Language: en Regarding parasite acquisition, the meta-analysis reveals an efficient tick infection following blood feeding in experimental settings, with 31 successful infections out of 37 attempts ( Table 4 ). While no significant factors were associated with parasite acquisition from an infected host (donor host), the analysis does indicate some trends worth discussing. Firstly, Argasidae ticks appear more likely to become infected compared to Ixodidae ticks when feeding on an infected host . The nature of the host does not seem to influence tick infection rates; however, the family of the parasite does impact infection rates. Specifically, ticks have a higher infection rate when feeding on a Trypanosoma -infected host compared to a Leishmania -infected host, with tick infection being more efficient when they take a blood meal from a host infected with Trypanosoma ( Table 4 ). Section title: Discussion Educational score: 4.170428276062012 Domain: biomedical Document type: Study Language: en Trypanosoma cruzi and T. evansi are particularly likely to infect ticks following blood feeding. These observations may relate to the intrinsic ability of trypanosomes to multiply in the blood of the infected host, increasing their availability to ticks during the blood-feeding process. Additionally, the disparity in infection rates might be attributed to differing feeding behaviors between the two tick families: Ixodidae ticks attach to the host's skin and feed slowly over several days, whereas Argasidae ticks rapidly ingest large volumes of blood in a short time (20–70 min), facilitating a more efficient uptake of infectious agents, especially under experimental conditions . Section title: Discussion Educational score: 4.217223167419434 Domain: biomedical Document type: Study Language: en The rapid feeding behavior of Argasidae ticks enhances their efficiency at acquiring blood-circulating parasites like T. brucei or T. evansi , compared to the slower-feeding Ixodidae ticks, which may be less effective at acquiring tissue-located parasites. Furthermore, the prolonged feeding process of Ixodidae ticks, lasting up to two weeks, exposes engorged pathogens to the full spectrum of host defense mechanisms, including specific acquired immunity that may impact the survival of Trypanosomatidae . Section title: Discussion Educational score: 4.058027267456055 Domain: biomedical Document type: Study Language: en Information gathered on the efficiency of infection through the injection of contaminated tick material provides insight into the presence of infectious parasitic stages in infected ticks. Our meta-analysis did not identify any significant factors related to the donor or receiver host, ticks, or parasites. While Argasidae ticks appear more efficient in such transmission than Ixodidae (7 successes out of 9 attempts compared to 7 successes out of 13 attempts), these differences are not statistically significant . Section title: Discussion Educational score: 4.10874080657959 Domain: biomedical Document type: Study Language: en Since ticks feed only once at each life stage, vertical transmission of pathogens is a crucial factor to consider when addressing the vectorial status of ticks for Trypanosomatidae parasites. The literature survey indicates that vertical transmission occurs in experimental settings, and only in Ixodidae ticks. Although not statistically significant, Leishmania seems more likely to be vertically transmitted in R. sanguineus than Trypanosoma species . Interestingly, Babesia can undergo transovarial transmission in ticks, suggesting potential similar behavior for Trypanosomatidae . However, the limited number of studies on vertical transmission restricts further discussion on the influence of tick identity or parasite species on vertical transmission. Section title: Discussion Educational score: 3.9495980739593506 Domain: biomedical Document type: Study Language: en Trypanosoma evansi and T. vivax are mechanically transmitted pathogens, meaning they are spread from host to host without undergoing biological replication within their vector. This mode of transmission does not align well with the feeding habits of ticks, except in instances of interrupted feeding . While there is limited data on T. vivax , a relatively good success rate of 3 out of 6 attempts was recorded for the transmission of T. evansi via tick blood feeding. Therefore, the transmission of T. evansi or T. vivax following interrupted blood feeding warrants further investigation. Section title: Discussion Educational score: 4.029436111450195 Domain: biomedical Document type: Study Language: en Salivarian trypanosomes, such as T. brucei , T. evansi , T. congolense , T. vivax , and Leishmania parasites, are transmitted through blood-feeding via the injection or regurgitation of saliva during the feeding process. In contrast, stercorarian trypanosomes, like T. cruzi , infect their hosts through the deposition of the pathogen on the host's skin during blood-feeding, subsequently entering the host through scratching of the infected blood onto mucosal surfaces. Infection via ingestion is also documented for T. cruzi . Section title: Discussion Educational score: 4.094152450561523 Domain: biomedical Document type: Study Language: en Considering this aspect, we observed more successful attempts to transmit Trypanosomatidae pathogens through the blood-feeding of infected ticks harboring salivarian trypanosomes, such as T. evansi , T . lewisi , and T. theileri , compared to those with stercorarian pathogens. Specifically, there were 11 attempts with 5 successes for salivarian trypanosomes, and 6 attempts for T. cruzi . The data indicate a general trend of higher infection rates for salivarian Trypanosomatidae during tick blood meals. However, these differences are not statistically significant, preventing us from drawing definitive conclusions about the impact of the transmission route. Section title: Discussion Educational score: 4.032049179077148 Domain: biomedical Document type: Review Language: en Overall, this systematic review and meta-analysis provide an updated overview of the vector status of ticks for Trypanosomatidae. This perspective highlights the limited information available regarding the presence of Trypanosomatidae infecting humans and animals of veterinary importance in field-collected specimens or during experimental studies. Specifically, data are available for 20 species out of the 774 recognized hard ticks and 221 soft ticks. Of the 23 Leishmania and 11 Trypanosoma species of medical or veterinary interest, we gathered information on 6 species from the Leishmania genus and 9 from the Trypanosoma genus. Notably, we also collected data on the presence of trypanosomes associated with human African trypanosomiasis ( T. b. gambiense and T. b. rhodesiense ) in field-collected ticks. Section title: Discussion Educational score: 4.132443428039551 Domain: biomedical Document type: Study Language: en However, we could not provide conclusive quantitative evidence regarding the vectorial role of ticks for Leishmania and Trypanosoma parasites in medical or veterinary contexts. For R. sanguineus, the documentation of Trypanosomatidae infecting humans and animals is the most extensive, with 21 studies. The capacity of this tick species to acquire parasites during blood feeding on infected hosts has been successfully demonstrated in 11 out of 15 experiments. Additionally, the presence of the infective parasite stage has been assessed through the injection of tick-infected material (7 attempts with 5 successes), as well as re-transmission via infected tick blood feeding (6 attempts with 3 successes). Importantly, data on vertical transmission have also been collected (9 attempts with 7 successes). Section title: Discussion Educational score: 4.114339828491211 Domain: biomedical Document type: Study Language: en While most of these collected data pertain to L. infantum , they collectively support the vectorial competence of R. sanguineus , which now needs to be more thoroughly demonstrated using advanced molecular methods in field-collected specimens alongside additional experimental evidence. Furthermore, the presence of Trypanosomatidae parasites with medical or veterinary significance in ticks is not uncommon, and ticks from the Argasidae family may also play a role in the transmission of these pathogens. The precise role of ticks in sustaining both the parasitic developmental and epidemiological cycles of Trypanosomatidae requires further investigation and continuous scrutiny. Section title: CRediT authorship contribution statement Educational score: 1.0361826419830322 Domain: other Document type: Other Language: en Tahar Kernif: Writing – review & editing, Writing – original draft, Visualization, Validation, Methodology, Investigation, Funding acquisition, Formal analysis, Data curation, Conceptualization. Bachir Medrouh: Writing – review & editing, Formal analysis, Data curation. Naouel Eddaikra: Writing – review & editing, Data curation. Bruno Oury: Writing – review & editing, Writing – original draft, Formal analysis. Philippe Holzmuller: Writing – review & editing, Writing – original draft, Formal analysis, Data curation, Conceptualization. Denis Sereno: Writing – review & editing, Writing – original draft, Visualization, Validation, Supervision, Resources, Project administration, Methodology, Investigation, Funding acquisition, Formal analysis, Data curation, Conceptualization. Section title: Informed consent statement Educational score: 1.0266131162643433 Domain: other Document type: Other Language: fr Not applicable. Section title: Institutional review board statement Educational score: 2.780668258666992 Domain: biomedical Document type: Study Language: en The study was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Section title: Data availability statement Educational score: 0.7591282725334167 Domain: biomedical Document type: Other Language: en Data is contained within the article and Supplementary Material. Section title: Declaration of generative AI and AI-assisted technologies in the writing process Educational score: 0.9627800583839417 Domain: other Document type: Other Language: en During the preparation of this work the authors used ChatGPT 4.0 in order to correct grammar and spelling. After using this tool/service, the authors reviewed and edited the content as needed and take full responsibility for the content of the published article. Section title: Funding Educational score: 0.9258387684822083 Domain: other Document type: Other Language: en This research was funded by LeiSHeild-RISE MATI project , Grant Agreement N° 778298 . Section title: Declaration of competing interest Educational score: 1.0007256269454956 Domain: other Document type: Other Language: en The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Kernif Tahar reports financial support and travel were provided by 10.13039/501100000780 European Union . Sereno Denis reports financial support, administrative support, and article publishing charges were provided by 10.13039/501100000780 European Union . Denis Sereno reports a relationship with 10.13039/501100000780 European Union that includes: funding grants. Kernif Tahar reports a relationship with 10.13039/501100000780 European Union that includes: funding grants and travel reimbursement. No additional information If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Study | biomedical | en | 0.999996 |
PMC11698937 | Section title: Introduction Educational score: 3.9783661365509033 Domain: biomedical Document type: Review Language: en Atherosclerosis is the dominant cause for major cardiovascular events and premature death, with coronary artery disease (CAD) responsible for 10 % of all deaths in Australia . The Australian government recommends routine cardiovascular risk assessment for all individuals over the age of 40, with the goal of implementing lifestyle changes and/or therapeutic treatment in susceptible individuals to reduce the burden of CAD . The Framingham equation, originally devised in 1998 using traditional risk factors to predict cardiovascular risk in asymptomatic individuals , has been reported to be used in 44 % of online risk calculators and used by 42 % of general practitioners to inform disease management . Section title: Introduction Educational score: 4.029385566711426 Domain: biomedical Document type: Study Language: en However, cardiovascular risk scoring (CVRS) is an imperfect tool. Between 14 and 27 % of first-time myocardial infarction (MI) patients have no standard modifiable risk factors (SMuRFs) . Albarqouni et al. found that the Framingham equation and the pooled cohort risk equation for atherosclerotic cardiovascular disease (PCE-ASCVD) incorrectly predicted 16 % of males and 31 % of females as non-high-risk despite them experiencing a cardiovascular event. Cardiovascular risk estimation errors have been the subject of considerable debate, with the potential to lead to overtreatment (in the absence of significant disease in apparently high-risk individuals) or no treatment (in the presence of severe disease in apparently non-high-risk individuals). This mismatch between apparent risk and actual atherosclerosis burden may increase the risk of a potentially fatal, but preventable, coronary event . Section title: Introduction Educational score: 3.9637644290924072 Domain: biomedical Document type: Review Language: en Evaluation of CAD plaque burden can be enhanced by coronary artery calcium score (CACS) identified by non-contrast CT , as increasing Agatston-units of coronary calcium are associated with adverse survival . Further, non-invasive coronary computed tomography angiography (CCTA) adds important prognostic information by demonstrating the presence and extent of CAD , and predicts cardiovascular events after adjustment for CVRS . However CCTA is not risk-free and has financial implications, and as such its role in preventative cardiology has not been entirely defined . Section title: Introduction Educational score: 4.089153289794922 Domain: biomedical Document type: Study Language: en There is a significant knowledge gap as to whether cardiovascular risk scoring accurately predicts the presence and extent of CAD in asymptomatic, but potentially at-risk, individuals. The aim of this study was to examine asymptomatic individuals (and no prior history of cardiovascular disease (CVD)) undergoing CCTA for cardiovascular risk assessment, to explore the predictive accuracy of CVRS in detecting the presence and extent of pre-clinical CAD. Section title: Study design and population Educational score: 2.3582255840301514 Domain: biomedical Document type: Study Language: en This was a sub-study of a retrospective observational cohort study of patients undergoing CCTA for cardiovascular risk assessment. The University of Notre Dame Human Research Ethics Committee approved this study and granted a consent waiver due to the low-risk nature. Section title: Study design and population Educational score: 3.8647162914276123 Domain: biomedical Document type: Study Language: en The initial cohort consisted of all consecutive patients undergoing CCTA at Perth Radiological Clinic (PRC) in Perth, Western Australia, between January 1, 2018 and December 31, 2019. Patients were excluded if they had a Medicare indication for CCTA (symptoms suggestive of CAD, for exclusion of a coronary anomaly, and/or prior to non-coronary cardiac surgery) or a prior CVD diagnosis, if they were outside of the required age range of 35–74 years old for CVRS calculation, or if any required information to calculate CVRS was missing . Section title: CCTA data extraction Educational score: 4.154435157775879 Domain: biomedical Document type: Study Language: en The radiologist report from the PRC CCTA results was transcribed by AI-based Natural Language Processing (NLP) through the Australian Institute for Machine Learning (AIML) at the University of Adelaide into “Database 2”. The NLP extracted information on CACS, and radiologist-reported coronary artery findings including presence, extent and severity of plaque, calcification, and location (left anterior descending, circumflex, right coronary and left main arteries). The NLP was trained using manually extracted examples and tested on a separate dataset not previously seen by the AI, and two cardiologists manually verified the output in 200 randomly selected scans. For CACS, NLP accuracy was 99.5 %, recall 100 % and precision 99.3 %; for the presence of atherosclerosis, accuracy was 99.5 %, recall 100 % and precision 99.3 %; and severe vs non-severe stenosis had 99.5 % accuracy, recall 98.7 % and precision 95.7 %. Section title: Degree of atherosclerosis Educational score: 4.070624351501465 Domain: biomedical Document type: Study Language: en Three categorical variables were obtained from the CCTA and CACS results and classified according to the Coronary Artery Disease-Reporting and Data System 2.0 (CAD-RADS 2) : CACS in Agatston units (classified as no calcium (0), mild (1−100), moderate (101−300) and high (>300) calcium burden), plaque extent (number of abnormal arteries with ≥1 coronary segment involved) and stenosis severity (either severe (≥70 %) or non-severe (<70 %) from the most severe artery). These numerically categorized variables were added together, with the resultant sum categorized as no atherosclerosis and low plaque-burden, moderate plaque-burden and extensive plaque-burden atherosclerosis. A binary categorical variable was created to record atherosclerosis presence (plaque present and/or non-zero CACS) and atherosclerosis absence (no zero plaque and zero CACS). Section title: Clinical data extraction Educational score: 4.086507797241211 Domain: biomedical Document type: Study Language: en Three pathology providers (Clinipath Pathology, Australian Clinical Laboratories and Western Diagnostic Pathology) extracted the most recent blood test result prior to the CCTA scan for each patient, and these databases were merged to form “Database 1” (linked by their Medicare ID). Sex, medical and cardiac history (smoking status, diabetes diagnosis and previous CVD diagnosis), current medications, and at least three systolic blood pressure readings (mmHg) taken during the CCTA visit were obtained from three patient questionnaire forms in PRC records . This was transcribed into “Database 3” using a combination of manual imputation for the handwritten information, and NLP for the tick-box information . These identifiable databases were merged on a patient-level (linked by a randomly generated study ID) into an SPSS datafile, and then all identifying information was destroyed after manual verification and data cleaning (merging duplicate cases into single patient rows). Only the Principal Investigator and honors student had access to the identifiable information (protected by a16-character alphanumeric password) and take responsibility for its integrity, and additional researchers only had access to the de-identified master database. See Supplemental Fig. 3. Section title: Cardiovascular risk scores Educational score: 4.079187393188477 Domain: biomedical Document type: Study Language: en Each medical record was examined for lipid-lowering medications, as use of these medications can cause underestimation of CVRS . When present, LDL adjustment was undertaken using composite scores from population data on each dose and type of statin , and corrected according to The Dutch Lipid Clinic Network Score . For CVRS calculations, the measured total cholesterol was used in patients not taking lipid-lowering therapy, and adjusted LDL concentration was used to calculate the total cholesterol used for those taking lipid-lowering therapy. Section title: Cardiovascular risk scores Educational score: 4.0451459884643555 Domain: biomedical Document type: Study Language: en A CVRS was calculated for each eligible individual using the Australian Absolute Cardiovascular Risk Calculator , using information on the individual's sex, age, systolic blood pressure, diabetes and smoking status, total cholesterol, and HDL cholesterol levels . Risk scores were classified as high risk (>15 %), moderate risk (10–15 %), low risk (1–9 %) or “zero” risk (>1 %) of experiencing a cardiovascular event in the next five years, with a maximum of 35 % . A binary categorical variable was created with a zero-low risk score (≤9 %) and moderate-high risk score (>9 %). Section title: Risk factor count Educational score: 4.009796142578125 Domain: biomedical Document type: Study Language: en The number of traditional risk factors for each individual was counted and categorized as low (0–2), moderate (3–4) or high (5–6). Risk factors included diabetes, diagnosed hypertension (≥140 mmHg systolic blood pressure), current smoking status or having ceased within the last 12 months, male sex, age 35 to 74 years old at the time of the CCTA scan, and hypercholesterolemia (total cholesterol level of ≥5.5 mmol/L) . Due to the possibility of a white-coat effect influencing measured blood pressure readings , only diagnosed hypertension was used as a risk factor. Section title: Statistical analysis Educational score: 3.9007108211517334 Domain: biomedical Document type: Study Language: en All analysis was performed with IBM SPSS, version 28.0.1.1, and statistical significance was set at p < 0.05. Normality was assessed using the Shapiro-Wilk statistic, and the distribution of CVRS was compared in individuals with and without atherosclerosis through the independent t -test or Mann-Whitney U test (95 % CI), as appropriate. Non-parametric continuous variables were reported as median and interquartile range (25th percentile, 75th percentile), and categorical variables were reported as frequencies and percentages. Section title: Statistical analysis Educational score: 4.106811046600342 Domain: biomedical Document type: Study Language: en The primary analysis of this study was to determine the predictive accuracy of risk scoring in detecting pre-clinical CAD. Degree of atherosclerosis was compared to CVRS using the Fisher-Freeman-Halton or Monte-Carlo tests (95 % CI) to determine the significance of the relationship, and a weighted Cohen's kappa analysis for the level of agreement. The same analysis was undertaken to compare degree of atherosclerosis and risk factor count, and to compare CVRS to plaque extent, stenosis severity and CACS. Section title: Statistical analysis Educational score: 4.098005771636963 Domain: biomedical Document type: Study Language: en The proportion of the cohort with a match, and mismatch, between their CAD and CCTA results was determined to calculate the percentage of overestimation and underestimation. A correct match was defined as any direct match between the categories of CVRS and degree of atherosclerosis (e.g., low plaque-burden and low risk) and a mismatch was any other combination (e.g., extensive plaque-burden and low risk). The relationship strength was visualized by relationship maps and statistically tested. Proportions of the cohort with or without atherosclerosis, and with a moderate-high (>9 %) or zero-low (≤9 %) CVRS, was determined to calculate the sensitivity and specificity of the calculator and presented in a scaled rectangular diagram . With CCTA as the reference group, the potential to improve classification of patients at non-high-risk using CVRS was examined by calculating the proportion of individuals who would be reclassified as high risk. Section title: Statistical analysis Educational score: 3.889234781265259 Domain: biomedical Document type: Study Language: en The risk calculator accounted for the potential confounding variables of sex and age, and males and females were analyzed separately. For a sensitivity analysis, variables were compared between the groups included and excluded from analysis. An independent t -test or Mann-Whitney U test was done for age, and patient frequencies were compared for the categorical variables of gender, presence of atherosclerosis and degree of atherosclerosis. Section title: Study population Educational score: 4.067291736602783 Domain: biomedical Document type: Study Language: en The study flow chart is summarized in Fig. 1 . 828 patients met the inclusion criteria for this study. Of the total cohort of 8430 patients, 5519 had known CVD diagnosis or symptoms suggestive of CAD, were being evaluated for non-coronary cardiac surgery, or were missing at least one patient questionnaire form. A further 248 participants were outside of the required age range for CVRS calculation, and 1850 had at least one missing required blood measurement required. Another one patient was excluded because of the absence of a recorded CACS. Therefore, the analysis cohort consisted of 828 asymptomatic individuals with no prior history of CAD and sufficient data to calculate their CVRS. Fig. 1 Final cohort extraction. PRC indicates Perth Radiological Clinic; CCTA indicates coronary computed tomography angiography; CVD indicates cardiovascular disease. Fig. 1 Section title: Cohort characteristics Educational score: 4.188684463500977 Domain: biomedical Document type: Study Language: en Cohort characteristics are summarized in Table 1 . The median age was 58.6 years (IQR = 52.0, 65.3), with 358 (43.2 %) females and 470 (56.8 %) males. Low CVRS (1–9 %) was the most common subgroup of calculated 5-year risk (239 (50.9 %) males and 244 (68.2 %) females). Atherosclerosis to any extent was identified in 78.5 % (369) of males and 50.0 % (179) of females. A non-zero CACS was found in 386 (46.6 %) patients in the whole cohort (66.8 % male), with a median Agatston Unit of 2 (IQR = 0, 112) for males and 0 (IQR = 0, 15) for females. At the time of the CCTA, 144 (17.4 %) patients were prescribed lipid-lowering medication. Table 1 Cohort clinical characteristics. Table 1 Males ( n = 470) Females ( n = 358) Age, y, median (IQR) 57.35 (5, 18) 60.18 (3,11) Hypertension, n (%) 183 (38.9 %) 140 (39.1 %) Hypercholesterolemia, n (%) 212 (45.1 %) 120 (33.5 %) Diabetes, n (%) 38 (8.1 %) 31 (8.7 %) Smoking, n (%) 193 (41.1 %) 120 (33.2 %) Blood pressure (mmHg), mean (SD) 131.84 (15.45) 130.64 (17.94) Total cholesterol (mmol/L), mean (SD) 5.90 (1.64) 6.03 (1.53) HDL cholesterol (mmol/L), mean (SD) 1.33 (0.32) 1.67 (0.46) Risk factor count a , n (%) Low 82 (17.4 %) 216 (60.3 %) Moderate 344 (73.2 %) 139 (38.8 %) High 44 (9.4 %) 3 (0.8 %) Cardiovascular risk score (%), median (IQR) 9 (5, 18) 5 (3, 11) Cardiovascular risk score category b , n (%) Zero 1 (0.2 %) 12 (3.3 %) Low 239 (51.0 %) 244 (68.0 %) Moderate 84 (17.9 %) 29 (8.1 %) High 145 (30.9 %) 74 (20.6 %) Degree of atherosclerosis category, n (%) Low plaque-burden 147 (31.3 %) 72 (20.1 %) Moderate plaque-burden 85 (18.1 %) 39 (10.9 %) Extensive plaque-burden 137 (29.1 %) 68 (19.0 %) No atherosclerosis 101 (21.5 %) 179 (50.0 %) IQR indicates interquartile range, expressed as 25th percentile, 75th percentile; SD indicates standard deviation; HDL indicates high-density lipoprotein. a Low (1–2 risk factors), moderate (3–4 risk factors), high (5–6 risk factors). b “Zero” (<1 %), low (1–9 %), moderate (10–15 %) and high (>15 %) risk of experiencing a cardiovascular event in a 5-year period. Section title: Cohort characteristics Educational score: 4.130610466003418 Domain: biomedical Document type: Study Language: en The continuous variable of CVRS was not normally distributed for males (W = 0.83, p < 0.001) or females (W = 0.69, p < 0.001), and homogeneity of variance was not assumed for males (F(1,468) = 8.69, p = 0.003) but was assumed for females (F(1,365) = 3.70, p = 0.055). The median risk score for males and females was, for the atherosclerosis group, 11 % and 7 %, and for the no atherosclerosis group, 5 % and 4 %, respectively. Significant differences in CVRS distribution were found between those with atherosclerosis and those without, in males (Mann-Whitney U 95 % CI: U = 26,533.00, n 1 = 369, n 2 = 101, p < 0.001) and females (U = 20,579.00, n 1 = 179, n 2 = 179, p < 0.001), shown in Fig. 2 . Fig. 2 Distribution of cardiovascular risk score in individuals with and without atherosclerosis. Evidence of atherosclerosis indicates a detected abnormality in coronary computed tomography angiography and/or a non-zero coronary artery calcium score. Fig. 2 Section title: Mismatch analysis Educational score: 4.1092209815979 Domain: biomedical Document type: Study Language: en The mismatch between CVRS and degree of atherosclerosis is shown in Fig. 3 . Of those with extensive atherosclerosis (137 males, 68 females), 47 (34.3 %) males and 38 (55.9 %) females had a low CVRS (1–9 %), and of those with no atherosclerosis (101 males and 179 females), 15 (14.9 %) and 27 (15.1 %) respectively were classified as high risk (>15 %). Additionally, of those with a low CVRS (238 males, 245 females), 47 (19.7 %) males and 38 (15.5 %) females had extensive atherosclerosis and of those with a high CVRS (147 males, 72 females), 15 (10.2 %) and 27 (37.5 %) respectively had no atherosclerosis. For males ( n = 470), CVRS overestimation occurred in 43.0 % (202), underestimation in 25.7 % (121) and correct estimation of atherosclerosis risk in 31.3 % (147). In females ( n = 358), overestimation occurred in 55.9 % (200), underestimation in 21.5 % (77) and correct estimation in 22.6 % (81). Fig. 3 Proportion of individuals in each comparison group between cardiovascular risk score and degree of atherosclerosis categories. Category of risk score is “zero” (<1 %), low (1–9 %), moderate (10–15 %), high (>15 %) risk of experiencing a cardiovascular event in 5 years. Fig. 3 Section title: Mismatch analysis Educational score: 4.121551036834717 Domain: biomedical Document type: Study Language: en A significant relationship (Monte-Carlo 95 % CI: male, p < 0.001; female, p = 0.024) but little to no agreement (Cohen's kappa: male, κ = 0.149; female, κ = 0.096) was found between degree of atherosclerosis and CVRS for both sexes, with low data accuracy (male, 2.2 %, κ 2 = 0.022; female, 0.9 %, κ 2 = 0.009). For CACS, a significant relationship (male, p < 0.001; female, p = 0.008) but little to no agreement (male, κ = 0.108; female, κ = 0.084) was found with CVRS for both sexes. Similarly for plaque extent, a significant relationship was found with CVRS for males ( p < 0.001), but an insignificant relationship for females ( p = 0.121), with little to no agreement for males ( κ = 0.110) and females ( κ = 0.080). Finally for stenosis severity, a significant relationship (male, p < 0.001; female, p = 0.012) but little to no agreement (male, κ = 0.035; female, κ = 0.030) was found with CVRS for both sexes. Section title: Mismatch analysis Educational score: 4.116332054138184 Domain: biomedical Document type: Study Language: en The relationship between the degree of atherosclerosis and CVRS is shown in Fig. 4 , with line thickness indicating relationship strength and color representing a match or mismatch. In males, a strong relationship was observed between low risk and no atherosclerosis as well as low burden atherosclerosis (count = 75, 78), and between extensive atherosclerosis and high risk (count = 54). However, a moderate relationship was observed between extensive atherosclerosis and low risk (count = 47) and between low burden atherosclerosis and high risk (count = 45). For females, the only strong relationship was between no atherosclerosis and low risk (count = 132). The relationship between low risk and extensive atherosclerosis (count = 38) and high risk and no atherosclerosis (count = 27) was stronger than between high risk and extensive atherosclerosis (count = 19). As shown in Fig. 5 , for both sexes, there is a substantial proportion of low-risk individuals with demonstratable atherosclerosis. Of the 369 males and 179 females with atherosclerosis, 44.2 % (163) and 65.4 % (117) were classified as zero or low risk, respectively. The sensitivity of the risk calculator for males and females was determined to be 89.2 % and 61.4 %, and the specificity 31.8 % and 54.5 %, respectively. Fig. 4 Relationship maps comparing degree of atherosclerosis categories and cardiovascular risk score. The red and orange lines represent a mismatch (red = severe, orange = not severe), and the green lines represent a match, between the categories. The line thickness represents the relationship strength (relationship count, the number of patients in that comparison group) and the circles represent categories of each variable, with the size correlating to patient count. Fig. 4 Fig. 5 Proportions of individuals classified as high risk and low risk, and who had detected atherosclerosis. CVRS indicates cardiovascular risk score, and high-risk is moderate-high (>9 %) and low-risk is zero-low (≤9 %). Created using custom srd software (Roger Marshall, PhD). Fig. 5 Section title: Mismatch analysis Educational score: 4.085894584655762 Domain: biomedical Document type: Study Language: en Assuming the 147 males and 72 females with a high CVRS remain in this category even if CCTA did not demonstrate atherosclerosis, we calculated the potential for CCTA to reclassify the 239 males and 257 females with a CVRS of ≤9 % according to their actual observed plaque-burden. Identifying a moderate to high plaque-burden would reclassify 84 males (35.1 %) and 63 females (24.5 %) to a CVRS of >9 %. Identifying any atherosclerosis would reclassify 163 men (68.2 %) and 117 women (45.5 %) to a CVRS of >9 %. Section title: Risk factor counting Educational score: 4.088512420654297 Domain: biomedical Document type: Study Language: en The risk factor count and degree of atherosclerosis mismatch is observed in Fig. 6 . Of the 137 males and 68 females with extensive atherosclerosis, 16 (11.7 %) and 32 (47.1 %) respectively had only one or two risk factors. Of the 101 males and 179 females without atherosclerosis, 76 (75.2 %) and 55 (30.7 %) respectively had more than three risk factors. A non-significant relationship between risk factors and atherosclerosis was found for males (Monte-Carlo 95 % CI: p = 0.101) and a significant relationship for females ( p < 0.001), but little to no agreement in both sexes (Cohen's kappa: male, κ = 0.027; female, κ = 0.044), indicating low data accuracy (male, 0.1 %, κ 2 = 0.001; female, 0.2 %, κ 2 = 0.002). Fig. 6 Comparison of risk factor count and degree of atherosclerosis categories. Risk factor count is categorized as low (1–2 risk factors), moderate (3–4 risk factors) and high (5–6 risk factors). Fig. 6 Section title: Sensitivity analysis Educational score: 3.820134401321411 Domain: biomedical Document type: Study Language: en Of the total cohort with missing data , 2447 (44.8 %) were female and 3016 (55.2 %) were male, with a median age of 59.7 years (IQR = 52.4, 66.3). The age distribution was similar to the analysis cohort for both sexes (males, U = 748,426.00, p = 0.065; females, U = 466,714.50, p = 0.081). In this cohort, no atherosclerosis was reported in 1051 (43.0 %) females and 739 males (24.5 %). Section title: Discussion Educational score: 4.090258598327637 Domain: biomedical Document type: Study Language: en To our knowledge, this is the first study to demonstrate a substantial mismatch between predicted CVRS and the extent of CAD identified using CCTA in asymptomatic individuals with no prior CAD history. Although subclinical CAD was detected more frequently in those with higher risk scores, agreement between degree of atherosclerosis and CVRS was poor. Importantly, a low CVRS was calculated in 34 % of males and 56 % of females found to have extensive CAD. At least some mismatch was identified in 69 % of males and 77 % of females, highlighting that CVRS is not reliable in predicting CAD. This has important implications in clinical practice, particularly in apparently low risk individuals who may be falsely reassured against the presence of CAD. Section title: Discussion Educational score: 4.334629058837891 Domain: biomedical Document type: Study Language: en Pen et al. used a similar methodology to investigate the discordance between Framingham risk score (FRS) and CCTA-defined atherosclerosis burden, however most patients in their US-based cohort had chest pain or other symptoms suggestive of CAD. Consistent with our findings, they found a weak association between plaque-burden and FRS, with 47.6 % of low FRS-risk patients having detected atherosclerosis. Their analysis compared FRS to total plaque score (TPS) obtained by CCTA, and did not consider plaque location, stenosis severity or the number of affected arteries, as addressed in the present study. Most prior studies assessing CVRS reliability have investigated subsequent cardiovascular event rates instead of the presence and burden of atherosclerosis in asymptomatic individuals. It is consistently demonstrated that untreated high-risk individuals have high event rates , highlighting the importance of aggressive risk factor reduction. Conversely, relatively few CV events occur in low-risk individuals, however due to the high proportion of apparently low-risk individuals in the community, the largest total number of events occur in this group . This highlights a significant unmet need to identify those individuals not traditionally considered high-risk, but who will subsequently have a cardiovascular event . Vernon et al. reported that, of those hospitalized with an MI, 25 % did not have any traditional risk factors and had a higher mortality risk than those with at least one risk factor . Similarly, we demonstrated that 12 % of males and 47 % of females with extensive atherosclerosis had only one or two traditional risk factors, with poor agreement between CVRS and degree of atherosclerosis for both sexes. Although better than chance alone, CVRS used in isolation would leave many non-high-risk patients with undetected CAD, including apparently low-risk individuals with extensive disease, potentially leading to a fatal coronary event. Additionally, we observed CVRS overestimation in approximately half of the cohort, leading to potential over-treatment in the absence of disease. This overestimation tendency has been reported by others , however we found a larger proportion of overestimated patients, suggesting that CVRS may have a more important role in prediction of a future cardiovascular event risk, than that of subclinical CAD. Therefore, mechanisms other than atherosclerosis may contribute to cardiovascular events, although identifying asymptomatic CAD may be seen as an opportunity to detect-and-treat prior a fatal event. Recent findings by Medina et al. demonstrated reasonable performance of CVRS in predicting future cardiovascular events, with only 2.3 % of non-high-risk individuals experiencing an event, although CCTA or CACS were not examined in this study. Section title: Discussion Educational score: 4.015231132507324 Domain: biomedical Document type: Review Language: en Outside of the potential benefits of CCTA, CACS has emerged as the single best predictor of subsequent coronary events in asymptomatic individuals . Hoffman et al. demonstrated that in those with a low CVRS (<6 %), 32 % of men and 23 % of women had a non-zero CACS. Further, Venkataraman et al. identified 77 % of patients with CACS>100 that were classified as low-risk. Hence, CACS has been recommended to form part of standard cardiovascular risk assessments in middle aged and older non-high-risk individuals . Beyond this, Hadamitzky et al. reported that CCTA provides better prediction of future cardiovascular events than CVRS and reinforces that identification of subclinical atherosclerosis may have important prognostic implications in otherwise low-risk patients. Section title: Discussion Educational score: 3.9912238121032715 Domain: biomedical Document type: Study Language: en The mismatch between CVRS and presence and extent of CAD is likely explained by the combination of environmental influences and non-traditional risk factors that can influence atherosclerosis development, such as additional lipoproteins not considered in CVRS [such as Lp(a)], genetic loci , psychosocial factors , and exercise and diet . However, it is not currently viable to assess all potential non-traditional risk factors across a population. Similarly however, although CCTA may reveal the final atherosclerotic result of exposure to risk factors, it is also not feasible to deploy such imaging across a population of apparently low-risk individuals. Additional research is needed to identify which apparently low-risk individuals would benefit from a more intensive search for atherosclerosis including CCTA. Section title: Limitations Educational score: 4.029776573181152 Domain: biomedical Document type: Study Language: en It is important to note that we excluded patients with known CVD and symptoms suggestive of CAD. In addition, this study has limitations to its applicability to a broader population. A selection bias is likely since patients were referred for CCTA presumably because of clinical uncertainty by the referring doctor. Further, since CCTA for a cardiovascular risk assessment in asymptomatic individuals is not Medicare-funded in Australia , the scan cost could be a potential source of bias. While the proportion of individuals with atherosclerosis in this cohort is likely larger than that of the general population, the study still illustrates the limitations of current CVRS techniques compared with the gold standard of CCTA for atherosclerosis assessment. Finally, we cannot exclude the possibility that the missing data, due to the retrospective nature of this study, may have influenced the measured outcomes. However, a sensitivity analysis confirmed that the excluded sample had similar characteristics to the final analysis cohort. Section title: Conclusions Educational score: 4.085813045501709 Domain: biomedical Document type: Study Language: en In asymptomatic individuals with no CVD history undergoing CCTA, CVRS does not reliably predict the presence or extent of CAD. A mismatch between CVRS and the degree of CAD (identified by CCTA and CACS) was found in majority of the cohort, and extensive CAD was observed in a significant proportion of individuals who otherwise appeared to be at low-risk. This highlights a potential role for CCTA in non-high-risk individuals with clinical uncertainty, where reclassification of risk based on cardiovascular imaging may influence treatment decisions (i.e., initiation of lipid-lowering therapies). Randomized prospective studies are required to address whether such an approach will improve outcomes in Australia. Section title: CRediT authorship contribution statement Educational score: 0.9322636723518372 Domain: other Document type: Other Language: en Emma Playford: Data curation, Formal analysis, Investigation, Methodology, Software, Visualization, Writing – original draft, Writing – review & editing. Simon Stewart: Conceptualization, Methodology, Supervision, Writing – review & editing. Gerard Hoyne: Methodology, Supervision, Writing – review & editing. Geoff Strange: Writing – review & editing. Girish Dwivedi: Conceptualization, Writing – review & editing. Christian Hamilton-Craig: Writing – review & editing. Gemma Figtree: Writing – review & editing. David Playford: Conceptualization, Data curation, Funding acquisition, Methodology, Project administration, Resources, Writing – review & editing. Section title: Funding Educational score: 0.9157079458236694 Domain: other Document type: Other Language: en This study was funded by an Investigator-Initiated Grant from the Perth Radiological Clinic Foundation . Section title: Declaration of competing interest Educational score: 0.933893620967865 Domain: other Document type: Other Language: it None. | Review | biomedical | en | 0.999995 |
PMC11698939 | Section title: Introduction Educational score: 2.169595956802368 Domain: other Document type: Other Language: en Biochar is a carbon-rich material produced through pyrolysis of different feedstocks, such as wood, crop residues, or manure, in the absence of oxygen, typically containing around 85% more carbon than the original biomass . Section title: Introduction Educational score: 3.270779848098755 Domain: other Document type: Other Language: en The modification of feedstocks or pristine biochar can be classified into three different types: activated biochar (AB), engineered biochar (EB), and functionalized biochar, based on the methods used to alter the biochar. AB is produced by exposing biochar to high temperatures in the presence of certain gases (such as CO 2 or steam), which enhance its physicochemical properties , while EB is modified by changing the feedstock or adding compounds like metal ions (MgCl 2 and ZnCl 2 ) . Biochar modified by adding functional groups to enhance its chemical properties is referred to as functionalized biochar . However, the term B generally distinguishes between pristine and altered biochar. Section title: Introduction Educational score: 1.4167219400405884 Domain: other Document type: Other Language: en The studies regarding the use of MB in soil have shown a significant increase in recent years owing to numerous benefits, such as increasing soil fertility , improving water retention, reducing nutrient leaching , climate change mitigation , and carbon sequestration . The efficacy of biochar in soil can be disturbed by various factors, such as climate, application, and soil type. Additionally, the feedback from biochar application may not be consistent across all soils, as they were highly dependent on the physicochemical characteristics of the biochar . Section title: Introduction Educational score: 3.7838642597198486 Domain: biomedical Document type: Review Language: en Given the limitations mentioned earlier associated with the utilization of pristine biochar in soil, there is a notable shift toward the adoption of MB . Thus, by adjusting the physicochemical properties of biochar, it becomes feasible to amplify its beneficial effects while concurrently mitigating any adverse impacts on plant growth and soil health . However, before choosing any modification technique, it is imperative to have a comprehensive understanding of the various physicochemical properties of biochar that have been discovered and subjected to modification, as well as their respective advantages and limitations. Thereby, this review article provides an in-depth discussion of recent advancements in the understanding of physicochemical characteristics of MB, including surface area, porosity, alkalinity, pH, elemental composition, and functional groups . Additionally, it also highlights the factors that can influence the efficacy of MB in soil . Fig. 1 The number of published articles per year for a period from 2010 to 2023 retrieved using keywords “activated biochar,” “functionalized biochar,” “engineered biochar,” and “pristine biochar.” MB: modified biochar Fig. 2 Fate and limitation of biochar in agricultural soils. Fig. 3 Physicochemical characteristics and analytical techniques of modified biochar. Fig. 4 Factors impacting the efficacy of modified biochar following soil applications. (For color interpretation, the reader is referred to the Web version of this article) Fig. 5 Factors impacting the efficacy of modified biochar following soil applications. (For color interpretation, the reader is referred to the Web version of this article) Section title: Fate and limitations of biochar in agricultural soils Educational score: 3.1366376876831055 Domain: other Document type: Study Language: en Several researchers have reported numerous findings regarding the fate and beneficial aspects of biochar. Apropos of soil physical properties, biochar amendment has been shown to improve soil pore structures and aggregate stability, which apparently upgrades soil water holding capacity. However, soil texture contributes a critical role in acquiring such benefits; for instance, biochar amendment is more noticeable in sandy soils than in clay soils. Hence, the positive feedback of biochar is not similar for all soil types . Similarly, depending on pH and EC, different soil types react distinctively to the ash content delivered by biochar. The high levels of ash content can pose detrimental impacts on plants and may produce reactive oxygen species in soil . Section title: Fate and limitations of biochar in agricultural soils Educational score: 4.245893478393555 Domain: biomedical Document type: Study Language: en Similarly, the agronomical traits of plants can also be significantly improved by biochar application through upgrading nutrient cycling and soil environment . However, such positive effects may vary depending on the plant species and the targeted part of the plant because different plant species have distinct nutrient requirements, and biochar may not necessarily provide all the required nutrients. Biochar may also affect soil environmental conditions and the microorganism's diversity by disturbing the decomposition of organic matter, also known as the priming effect . The impact may arise from changes in microbial communities induced by biochar, potentially resulting in either heightened or diminished decomposition of native soil organic carbon (SOC), consequently influencing its stability . For example, microorganisms, specifically fungi species such as Ascomycota and Basidiomycota , are more effective at breaking down biochar and releasing nutrients for plant uptake, while others may be less efficient . Similarly, Dai et al. found a significant decrease (11%) in the relative abundance of Basidiomycota by easily mineralizable C from biochar. The aforementioned limitations can be managed by modifying biochar to enhance specific chemical properties such as pH, cation exchange capacity (CEC), surface area, functional groups, and nutrient content that are beneficial for the targeted plants or specific plant parts. For example, the modifying process introduces new substances such as nitrogen, phosphorus, and potassium, which can minimize the adverse effects on SOM (soil organic matter) decomposition and soil microbial communities by interrupting C:N:P ratios . Additionally, increasing the pH and CEC of biochar by activation and/or engineering methods can enhance its ability to retain nutrients and prevent leaching . Section title: Fate and limitations of biochar in agricultural soils Educational score: 4.018628120422363 Domain: biomedical Document type: Study Language: en Previously, Xu et al. reported that the combined application of biochar and phosphorus fertilizer in saline-sodic soil depicted a considerable decline in available P levels by accelerating phosphate precipitation/sorption processes owing to its high surface area and adsorption capacity . Hence, it can act as a sink rather than a P source for plants. Biochar modification by altering its surface area, pore size distribution, and functional groups, can increase or decrease its adsorption capacity for specific nutrients and help to regulate its selectivity for specific soil nutrients while reducing its affinity for others . Section title: Fate and limitations of biochar in agricultural soils Educational score: 3.4086129665374756 Domain: biomedical Document type: Study Language: en Previous studies enable us to refer that the capacity of biochar to adsorb essential nutrients such as nitrogen (N) or iron (Fe), sometimes surpasses the limits that are conducive to plant growth . If biochar adsorbs nutrients exorbitantly, it can lead to a reduction in their availability for plants, which can result in stunted growth or even plant death . Therefore, it is essential to carefully manage certain physicochemical characteristics to ensure that it does not have a negative impact on plant growth by competing with the plants for these essential nutrients. This can be achieved by using MB that has been specifically tailored to the needs of the soil and the plants being grown . Section title: Fate and limitations of biochar in agricultural soils Educational score: 2.184802770614624 Domain: biomedical Document type: Other Language: en Furthermore, the adsorption abilities of biochar can be selective and biased towards certain pollutants, which can affect the effectiveness of pesticides, the concentration of heavy metals, and even plant defense mechanisms . However, researchers are exploring ways to adjust the surface chemistry of biochar to improve the targeted removal of specific pollutants while minimizing any negative impacts on plant growth and defense . Section title: Physicochemical characteristics of modified biochar Educational score: 4.407086372375488 Domain: biomedical Document type: Study Language: en The physicochemical characteristics of MB (Table 1 ) vary based on various alteration techniques, pyrolysis temperature, and the kind of feedstocks and modifying compounds (Table 2 ). This section discusses how different modification methods and agents improve the physical and chemical characteristics of MB . i. Surface Area and Pore spaces Table 1 Overview of essential characteristics of biochar Property Definition Reference Anion exchange capacity (AEC) The potential of biochar to adsorb anions Ash content These residues are non-combustible byproducts resulting from pyrolysis, originating from mineral and inorganic constituents of biochar Cation exchange capacity (CEC) The potential of biochar to adsorb cations Density Density refers to the mass of a substance divided by its volume, factoring in any spaces between particles. A lower density indicates a lighter weight per unit volume Electric conductivity It signifies the conductivity of a material, indicating its capacity to conduct electric current Elemental composition It represents the mole ratios of oxygen (O), carbon (C), hydrogen (H), nitrogen (N), and sulfur (S). Typically, the ratios of O/C and H/C moles are used as indicators of the degree of carbonization, where low ratios often indicate a higher stability of biochar Fixed carbon content The extent of carbonization can be inferred from the fixed carbon content, which is derived by subtracting the percentages of moisture, volatile matter, and ash from a given biochar sample. This calculation is expressed by the formula: FC (%) = [100 − (VM + Ash)] Heating value A metric denoting the utmost thermal energy accessible from complete combustion, often referred to as energy content, is defined as the heat produced per unit mass or per unit volume Hydrophobicity The attraction or affinity of biochar toward the water Mass yield An indicator of biochar production efficiency, denoting the ratio of the mass of pyrolyzed products to the mass of raw biomass pH-value An indicator of the alkalinity or acidity of biochar, expressed as pH, which is calculated using the formula pH = − log[H +] Pore volume and pore size distribution The cumulative volume of pores and voids within biochar defines its pore space. The distribution of pore sizes signifies the proportional occurrence of each pore size within the structure of biochar Porosity The ratio of the volumes of voids or pore space within a substance divided by the total volume of that substance is known as the porosity Specific surface area (SSA) The SSA of a substance, calculated as the total surface area per unit mass, serves as an indicator of both adsorption capacity and water retention ability in biochar Stability The percentage of original carbon content that remains following both abiotic and biotic degradation signifies the recalcitrance of the material in specific applications, such as carbon sequestration, under different conditions and time frames Surface functional group The functional groups found on the surface of biochar, such as carboxylic (-COOH), hydroxyl (-OH), amine, amide, and lactonic groups, enhance its sorption properties. These groups indicate the biochar's capacity to adsorb organic compounds and pollutants effectively, as well as its catalytic performance The functional groups present on the surface of biochar, including hydroxyl (-OH), carboxylic (-COOH), amine, lactonic, and amide groups, play a crucial role in enhancing their sorption properties. These groups are indicative of the biochar's ability to effectively adsorb organic compounds and contaminations, as well as its catalytic performance Water holding capacity The capacity of biochar to absorb and retain water Table 2 Overview of specific physicochemical characteristics of modified biochar used as a soil amendment Raw material Feedstock Activation Pyrolysis Temperature (°C) Modification Treatment SA (m 2 g −1 ) pH CEC (cmolc kg −1 ) C H O N Reference Plant Water hyacinth O 450 Post-treatment 32.48 10.3 3.53 46.7% – – 2.53% Fe 155.91 9.4 6.35 50.3% – – 3.57% Mn 34.34 9.4 3.73 47.6% – – 3.05% Zn 95.65 8.8 6.04 50.4% – – 3.14% Cu 62.11 9.4 3.93 49.1% – – 3.46% Pine chips HCl 400 Post-treatment - 2.5 17.4 608 g kg −1 – – 1,372 µg g −1 Peanut hull - 2.5 15.7 625 g kg −1 – – 1,8 µg g −1 Rice straw FeOS 300 Post-treatment 37.4 - - 37.4% 3.9% 0.8% 34.6% FeCl 3 40.9 - - 40.9% 4.7% 0.96% 30.8% Fe 38.5 - - 38.5% 3.4% 0.76% 23.6% Fe 3+ ( 1%) 500 Post-treatment 23.3 9.9 - 46.4% 2.8% 16.2% 2.23% Fe 3+ ( 5%) 26.4 5.7 - 43.8% 2.7% 15.8% 2.27% Fe 3+ ( 10%) 7.3 3.1 - 3.25% 2.5% 15.9% 1.72% FeCl 3 (1%) 14.6 10.2 - 45.5% 2.0% 11.2% 2.23% FeCl 3 (5%) 5.9 3.4 - 44.2% 2.1% 12.0% 2.32% FeCl 3 (10%) 5.7 3.1 - 44.1% 2.0% 13.8% 2.40% Corn stem Fe–Mn 600 Post-treatment 60.67 - - 72.6% 2.2% 4.7% 1.2% Platanus orientalis L Fe 650 Post-treatment 74.5 4.4 - 59.9% 0.9% – 2.2% Corn straws FeCl 3 600 Pre-treatment 4.1 2.5 - 38.0% 1.4% 27.7% 1.0% Rice hull NaOH 450 Post-treatment 396 6.5 3.2 77.9% 3.4% 15.7% 1.7% Cracking crop straws Commercial 500 - 22.9 8.3 – 414.7 g Kg −1 – – 14.36 g Kg −1 Rice straw Thiol 500 Post-treatment 0.34 2.3 – 43.7% 0.6% – – Wheat straw Mg 600 Post-treatment 292.5 – – 54.5% 2.3% 15.4% 0.5% Al 169.6 – – 46.8% 3.1% 16.9% 0.3% Mg–Al 268.5 – – 43.0% 2.0% 12.9% 0.4% Microbial 600 Pre-treatment 3.77 9.7 – 48.5% 5.8% – 0.6% Corn straw KMnO 4 600 Post-treatment 3.18 10.7 – 73.0% 0.7% 10.9% 0.3% Rice husks FeCl 3 600 Pre-treatment - 7.8 – 34.5% 1.0% 11.3% 0.3% Platanus orientalis L FeCl 3 650 Post-treatment 74.5 10.6 59.9 2.2 0.9 Carrot pulp Thiourea CH 4 N 2 S 550 Post-treatment – 9.1 59.18 47.2% 4.1% 23.2% 8.9% Cotton straws H 3 PO 4 500 Pre-treatment – – – 67.8% 4.1% 14.3% 0.11% NaOH – – – 68.2% 3.9% 6.5% 0.18% Corn straw Fe (NO₃)₃ 600 Post-treatment 207 9.8 1.0 68.0% 18% – 2.4% Animal Poultry manure Chitosan 450 Post-treatment 3.7 10.4 – 11.3% 1.2% – – Sheep manure 5.2 10.4 – 88.6% 1.0% – – Pig carcass FeCl 3 650 Post-treatment 18.4 10.6 30.8 1.3 2.1 CEC Cation exchange capacity, SA Surface area Section title: Physicochemical characteristics of modified biochar Educational score: 4.095783233642578 Domain: biomedical Document type: Study Language: en The specific surface area (SSA) and pore structure of biochar play a significant role in adsorption and regulating the nature of biochar as hydrophilic or hydrophobic . The general purpose of modification in pristine biochar is to expand its surface area, which ultimately modifies its functional groups and enhances its magnetic performance and catalytic capacity . Many studies showed that pyrolysis temperature and functionalization with innovative materials can enhance the SSA and porous structure of biochar . Rong et al. observed a significant surge in surface area in pre-mixed banana peel biochar with Fe 2 O 3 after hydrothermal carbonization. Their results illustrated an increment of 407, 504, 451, and 446 m 2 g −1 by combining with 0.05–1.0 g of the precursor solution, respectively. Similarly, Park et al. reported that during high pyrolysis temperatures (500–600 °C), the volume of pores in sesame straw increased from 0.0716 to 0.1433 cm 3 g −1 . Section title: Physicochemical characteristics of modified biochar Educational score: 4.160273551940918 Domain: biomedical Document type: Study Language: en Furthermore, in another research, it is depicted that the surface area of Saccharina japonica- derived biochar was positively influenced by the temperature, resulting in a notable increase (2.9–175 m 2 g −1 ), with the highest surface area achieved at 500 °C noted that ZnCl 2 − EBcan enhance the pore size up to 0.2–0.9 cm 3 g −1 . The BET (Brunauer, Emmett, and Teller) approach is frequently used to determine the SSA of biochar. In this method, the amount of N 2 adsorbed on the surface of the biochar is evident at low temperatures (77 K) . Apart from modification by nano-scale zero-valent iron and the effects of pyrolysis temperature, the subsequent impregnation of biochar with Mn or Mg enhances the surface area from 209.6 to 463.1, 12.68 to 174.29, and 244 m 2 g –1 , respectively . Section title: Physicochemical characteristics of modified biochar Educational score: 4.08697509765625 Domain: biomedical Document type: Study Language: en On the contrary, several studies have documented a decrease in the SSA of functionalized biochar. The decline in surface area could potentially be attributed to the pore openings or pores being obstructed by chitosan . Recently, manganese oxide activation revealed a considerable decrease in SSA ranging from 60.97 to 3.18 m 2 g −1 . Another research found that functionalized biochar through sulfur significantly affected surface area in contrast to pristine biochar. The highest surface area was observed in biochar generated at 500 °C and 700 °C (382 and 404 m 2 g −1 ), whereas functionalization with sulfur led to a significant reduction in surface area to 10.06 m 2 g −1 and 5.10 m 2 g −1 . Hence, it is crucial to thoroughly evaluate the characteristics of the final product concerning the impact of the modification process. ii. Elemental Composition Section title: Physicochemical characteristics of modified biochar Educational score: 4.183298110961914 Domain: biomedical Document type: Study Language: en Generally, the pristine biochar comprises 2–5% H, 45–60% C, and 10–20% O. Although the individual components employed to develop the product vary widely and rely on the feedstock. In order to assess the degree of hydrophobicity and carbonization in biochar, researchers commonly employed the O/C and H/C molar ratios . Additionally, it includes minerals, such as Si, P, Ca, Al, and K, that are prominent inorganic components of biochar . Many studies highlighted that type of feedstock, pyrolyzing procedures and functionalization may modify the properties of pristine biochar . In one study, Mn-oxide-MB illustrated a surge in O (10.9%) and Mn (7.41%) concentrations. Meanwhile, similar research observed that C, H, and N levels declined from 85.3–73.0%, 1.75–0.33%, to 0.80–0.72% . This reduction was attributed to the activation process wherein previously MB was exposed to additional high temperatures, leading to the further breakdown of C, H, and N and their conversion into ash . Section title: Physicochemical characteristics of modified biochar Educational score: 4.057669162750244 Domain: biomedical Document type: Study Language: en Furthermore, Wu et al. also reported a decline in H and C contents when biochar was magnetically modified with FeOS, Fe, and FeCl 3 . In FeOS biochar, C and H contents were the highest at C at 12.65% and 1.23%, while the lowest was in FeCl 3 -engineered at 9.16% and 0.28%, respectively. In addition to the mentioned modifications and their effects on the elemental constitution of biochar, various additional substances, such as chitosan and alkali/acid, have also demonstrated beneficial outcomes. Chitosan amendment resulted in a lower C percentage and increased H, O, and N ratios, confirming the inclusion of treated material on the surface of biochar . iii. Alkalinity and pH Section title: Physicochemical characteristics of modified biochar Educational score: 3.3090758323669434 Domain: biomedical Document type: Study Language: en The pH of typical biochar usually varies from neutral to alkaline and is highly dependent on the type of feedstock, thermochemical process, and functional material, while studies about acidic biochar are also present . During the high pyrolysis temperature, the acidic functional groups (bionic acid) decompose, elevating the pH of biochar and causing an increase in inorganic alkali metal ions . Additionally, several organic functional groups, including –COOH, –COO, –O, and –OH, can similarly raise the pH of biochar . Section title: Physicochemical characteristics of modified biochar Educational score: 4.054538249969482 Domain: biomedical Document type: Study Language: en In another study, Zhou et al. recorded pH values of different biochars prepared from bamboo (7.9), sugarcane bagasse (7.5), hickory wood (8.4), and peanut husk (6.9), but after chitosan modifications, pH values changed to more alkaline 8.2, 8.1, 8.6, and 7.3, respectively. Similarly, the pH of corncob biochar produced at 600 °C was shown to be neutral (7.17), but after being modified by Mg-oxide, it reduced considerably to 10.4 . On the contrary, FeCl 2 -impregnated biochar exhibited an acidic characteristic (4.87) contrasted to conventional biochar (10.7) . Section title: Physicochemical characteristics of modified biochar Educational score: 4.145008087158203 Domain: biomedical Document type: Study Language: en Moreover, hydrophilicity, hydrophobicity, sorption, and adsorption can be influenced by organic groups and linked with the buffering action of acid and base. Additionally, the organic groups present on the biochar surface carry negative charges, increasing the CEC . As the CEC of biochar increased, it ultimately surged in adsorption capacity . Biochar modification by surface oxygenation via dry ozonization proved a promising technique for enhancing the CEC 10 times, in contrast to conventional biochar . For instance, biochar derived from the limb of a pine tree and subjected to ozone gas for 1.5 h, the CEC of the biochar considerably elevated from 15.39 cmol kg −1 to 32.69 cmol kg −1 . Although this technique decreased the pH and demonstrated the oxygenic functional group formation of the biochar surface . iv. Functional Groups and Aromaticity Section title: Physicochemical characteristics of modified biochar Educational score: 3.949140787124634 Domain: biomedical Document type: Study Language: en Several functional groups are associated with the surface of biochar, such as carboxylic, hydroxyl, and phenolic functional groups that contribute significantly to the remediation of contaminated soils . Among them, the most prevalent are O-containing functional groups, which can additionally be classified into neutral, and alkaline groups according to their inherent characteristics. The carboxyl, lactonic, and phenolic groups are examples of acidic groups, while the chromene and pyrone groups are known as basic active sites . Their characteristics may be related to the carbon’s surface basic nature, which is more evident in carbon atoms without oxygen because of the existence of delocalized electrons . Section title: Physicochemical characteristics of modified biochar Educational score: 4.116367340087891 Domain: biomedical Document type: Study Language: en The pyrolysis temperature significantly influences the functional groups present on the biochar surface. It is found that C=C and –CH 2 functional groups could be successfully retained in pyrolysis, although C–O–C and –OH, C=O functional groups reduced with increasing pyrolysis temperature . Meanwhile, biochar’s water affinity, CEC, and polarity are regulated by oxygen-containing surface functional groups . Generally, the yield of biochar declines, while on the contrary, alkaline functional groups, pH, and ash concentration increase with increasing temperature . In a recent study, the adsorption capacity of MB derived from rice straw was observed to be higher than that of cotton straw-MB, likely due to the presence of additional functional groups . Section title: Physicochemical characteristics of modified biochar Educational score: 4.196619987487793 Domain: biomedical Document type: Study Language: en The aromatic π-system is known to be involved in significant types of noncovalent specialized engagements termed electron donor–acceptor (EDA) interactions . The aromatic structures of biochar can significantly enhance pollutant adsorption, as they act as electron donors or acceptors and create bonds with the pollutants in soil . Usually, the carboxyl functional groups on the surface of carbonaceous adsorbents serve as electron acceptors, whereas the hydroxyl groups behave as electron donors . The aromaticity of biochar, determined using O/C and H/C ratios is highly influenced by pyrolysis temperature. The biochar derived from plant residues contains higher aromaticity due to high carbon material concentration. The cellulose and lignin decompose into small molecules that ultimately reduce H/C and O/C ratios as a result of depolymerization or dehydration. On the other hand, biochar from animal fecal and sludge does not possess any lignocellulosic molecules and hence avoids the depolymerization process . Section title: Physicochemical characteristics of modified biochar Educational score: 4.143706798553467 Domain: biomedical Document type: Study Language: en In a recent sulfamethoxazole structural analysis research, it was observed that the N-heteroaromatic ring, unprotonated sulfonamide group, and amino functional group act as significant π -electron acceptors, although they possess a high capacity to donate electrons . Similarly, Zhao and Zhou also reported π − π EDA interactions between biochar aromaticity and sulfamethoxazole. However, potential electron-donating groups identified include the phenolic −COOH−C−O and −OH groups . v. Hydrologic Properties Section title: Physicochemical characteristics of modified biochar Educational score: 4.265081405639648 Domain: biomedical Document type: Study Language: en The ability of MB to resist water is a crucial quality that has a significant impact on soil water retention . But the water retention property of biochar is highly dependent on the source of feedstock, synthesis technique, wetting characteristics, and particle size . The temperature during pyrolysis significantly influences the hydrologic characteristics when biochar is applied to soils . The most favorable hydrologic qualities were reportedly found in acid-functionalized biochar generated at higher temperatures (400–600 °C); in such amendment, water holding capacity was 18.45–22.45% higher than the control. This surge in water retention can be a result due to (i) high surface area and pore spaces and (ii) more hydrophilic functional groups that aid functionalized biochar . Besides, Zn (23.85%) and Fe (22.45%), impregnated biochars also exhibited a considerable increase in water-holding capacity in soil against soil gravity losses —the mineral formation of Fe and Zn aids in water retention by increasing chemisorption and physisorption. For instance, hematite surfaces possess the capacity to sorb water 23–24 A 2 per molecule, allowing it to adsorb the polar water molecules . In contrast, the hydrologic properties of biochar are found to be independent of soil types, such as coarse-grained (non-cohesive) soil or fine-grained (cohesive) soil . The mechanical resilience of aggregates at both micro and macro-scales was enhanced in biochar-amended soils, leading to notable improvements in cohesion and compressive behavior . There are possibilities that the hydraulic characteristics of soil that have been treated with EB extensively correlate with the quality and content of biochar, but these interactions are inadequately understood . vi. Complexation and Van der Waals forces Section title: Physicochemical characteristics of modified biochar Educational score: 3.914869785308838 Domain: biomedical Document type: Study Language: en Complexation is a special ability of biochar for adsorption that indulges ligand exchange, and bridging ligands are used to transport electrons . The electron donors and acceptors engage to produce different compounds during the surface complexation. During the formation of these surface compounds, several polyatomic structures significantly improve the sorption potential of biochar . Besides, chelation is an exceptional kind of complexation that is described as an equilibrium process and distinguished by the development of a complex between organic molecules with more than one functional group (multiple bounds) and a single central atom . Section title: Physicochemical characteristics of modified biochar Educational score: 1.795750379562378 Domain: other Document type: Other Language: en Several biochar features indicated that it may be an extremely effective adsorbent for the majority of soil contaminants and metals. Although these properties are highly influenced by the source of feedstock, pyrolysis time, and temperature, sufficient consideration should emphasize the analysis techniques of biochars produced under different circumstances. Section title: Physicochemical characteristics of modified biochar Educational score: 3.9340412616729736 Domain: biomedical Document type: Study Language: en The functionalized biochar contains a larger surface area and more functional groups than pristine biochar, such as carboxylic, phenolic, and lactonic functional groups that act as electron acceptors while the product of low pyrolysis possesses more electron-donating functional groups including amino –NH 2 and hydroxyl –OH . The complexion potential of biochar can improve if it is pyrolyzed in the presence of oxygen because of more surface oxidation. It is observed that plant-derived engineered biochars have higher complexion capacities for heavy metals in soils as compared to poultry litter and dairy manure-derived biochars . Section title: Physicochemical characteristics of modified biochar Educational score: 4.180408477783203 Domain: biomedical Document type: Study Language: en The van der Waals forces, also known as hydrophobic interactions, refer to intermolecular interactions that bind molecules together. These interactions are divided into two types: (i) weak London dispersion forces and (ii) stronger dipole–dipole forces . The van der Waals forces possess relatively modest energy about 0.4–4 kJ mol −1 ), while most of the sorbates are associated with biochar nonspecifically (weak London dispersion forces) . These forces specifically contribute to interactions between carbonaceous sorbents and ionic organic compounds because of the larger molecular size of IOCs as van der Waals forces increase with increasing contact area, and the high van der Waals coefficient of activated carbon (graphite) . Section title: Physicochemical characteristics of modified biochar Educational score: 4.077558517456055 Domain: biomedical Document type: Study Language: en It is noted in a study that ZnCl 2 -MB enhanced the pore size up to 0.2 cm 3 g −1 to 0.9 cm 3 g −1 and the adsorption capacity of biochar via van der Waals forces . Similarly, montmorillonite-biochar composites pyrolyzed at 400 °C were also found to be highly effective for ammonium adsorption via Van der Waals interaction . Usually, the adsorption of organic pollutants on biochar occurs via weak physical adsorption without any strong chemical bonding. These weak bonds include hydrogen bonding, van der Waals forces, hydrophobic interactions, and electrostatic forces . Section title: Analytical techniques for modified biochar Educational score: 4.2118096351623535 Domain: biomedical Document type: Study Language: en The flexibility and interaction of biochar with soil are highly influenced by its various physical and chemical characteristics. Hence, a deep structural and physical analysis via appropriate methods has been proven beneficial . If left unaddressed, the presence of a non-carbonized layer may lead to fluctuations caused by soil contaminants or other materials, potentially yielding inaccurate results . A detailed summary of the physicochemical attributes of the MB employed in soil, along with a comprehensive overview of the advantages and disadvantages of the analytical techniques, is presented in Table 3 . Table 3 Summary of various analytical techniques of modified biochar Technique Utilization Advantages Limitation Evaluated Biochars Reference Scanning Electron Microscopy (SEM) • It is used to determine morphological differences between biochar surfaces and pores arrangement • Limited need for conductive coatings due to high gas pressure • High magnification can be obtained in a range between 300000x and 500000x • Not applicable for organic contaminants • Magnetic biochar (γ-Fe 2 O 3 ) • Magnetite (Fe 3 O 4 ) biochar • MgO biochar nanocomposites Energy Dispersive X-ray (EDX) • It can evaluate the biochar surfaces and mapping of abundant elements • Have the potential to precisely identify and assess the arrangement and existence of elements in the scanned domain • High-speed data collection and processing • Easy to handle • Only detect the elements that have higher atomic numbers than boron • Highly dependent on probe current and voltage • Not applicable for organic contaminants • S, Mn and Fe MB • Magnetic biochar (γ- Fe 2 O 3 ) Transmission Electron Microscopy (TEM) • TEM is used to determine the surface morphologies like SEM • It can also analyze the lattice constant and chemical composition of biochar • Very High magnification can be obtained in the range between 200000 and 1000000x • A multifunctional instrument that can be used for spectroscopy and nanoscale imaging • It requires a high degree of vacuum to restrict the electron scattering they travel from the electron source to the electron optics • Fe 3 O 4 Biochar • Biochar nanoparticles (wheat straw) X-ray Diffraction (XRD) • It can analyze the composition of biochar, such as crystalline C or other materials • It is also used to determine organic compounds, including cellulose, hemicelluloses, and lignin, as well as inorganic compounds, such as oxides and sulfides carbonates • A non-destructive technique that can produce 3D characterization of interface structure • It can be used with different combinations of in-situ methods • In-situ methods and Time resolution is possible • Requires high-intensity X-ray beam • The usage is limited to access time to synchrotron source and single crystal surfaces • S and Fe 3 O 4 -MB X-Ray Absorption Near Edge Structure (XANES)/ Near Edge X-Ray Absorption Fine Structure (NEXAFS) • XANES/NEXAFS used to investigate the surface chemistry of highly complex types of C materials, for instance, charcoal • It can be used to identify the C species and stability with several structures at different pyrolysis time intervals (100–700 °C) • Direct structural determination of any matter and isotope • Oxidation state and spin state direct determination • Spectroscopy carried out in bulk gives an average structure • Very little information about the angle of the structure determines • Synchrotron X-ray source required • Fe- EB • KOH steam–activated pecan shell biochar X-ray photoelectron spectroscopy (XPS) • It is effective for surface characterization of biochar (surface elemental composition) • It can analyze chemical bonds, chemical, and the presence of distinct species of elucidated compounds on the surface of biochar • It can carry sensitive surface quantitative analysis such as material composition and empirical formula (without hydrogen) • Have the potential to analyze the material up to the depth of 1–10 nm • This technique is only applicable to solids since a high vacuum is needed • Highly time-consuming and cannot recognize hydrogen and helium atoms • FeCl 3 , FeSO 4 , Fe/Ca, and Mn EB • MnO/NiO biochar composite Fourier‐transform infrared spectroscopy (FTIR) • It can investigate mineralogy and chemical functional groups of biochar • Variation in the carbonation degree also makes it possible to determine • The analysis can be performed on any matter (solid, liquid, or gas) • Fast and non-destructive data acquisition and processing • Mapping with a good special resolution of large surface samples is possible • The interpretation of data is difficult, especially when working with a complex matter • Aqueous mixtures are complicated to investigate because water has a high infrared absorption capacity • DOM/Cu MB • Fe/Mn EB Raman spectroscopy • This technique is effective in quantifying the structural characteristics, especially graphite structures of biochar • Functional groups and crystalline C structures can be evaluated as well • A precise single-point assessment carried out with an excellent special resolution • Spectra possess quantitative and qualitative information • It is feasible to acquire insight into the functional groups in the polymer • Measurement parameters variation may affect the signal (e.g., laser wavelength) that negatively affects data interpretation • Fe/Ca-EB • (NH 4 ) 3 PO 4 impregnated biochar • Magnetic biochar (γ-Fe 2 O 3 ) X-ray fluorescence spectroscopy (XRF) • Commonly utilized to evaluate the compounds of biochar • Determination of inorganic compounds present on the surface of biochar • Very effective in quantifying the composition of biochar • More powerful and precise for inorganic materials determination as compared to XRD • Very costly • Fe-EB • N and O activated Solid-state nuclear magnetic resonance (NMR) • The structural composition of biochar and carbonization degree and stability can be determined by this method • It can be used to evaluate the contents of functional groups such as aromatic hydrocarbons, phenolic, methoxyl, and aliphatic in a biochar • Findings for stability have strong correlations with several other techniques • It gives deficient signals/noise ratio when encountering with high temperature pyrolyzed biochar • Signals obscured in the presence of ferromagnetic materials • NaOH- MB • CO 2 and steam-activated biochar • N and O activated biochars Section title: Effects of modified biochar on soil attributes Educational score: 1.9449183940887451 Domain: other Document type: Other Language: en Modified biochar (MB) can alter soil functional groups, pore size, pore structure, surface area, and chemical properties. These modifications significantly impact soil quality by influencing its physical and hydraulic properties, nutrient profile, gas exchange characteristics, organic matter content, pH, electrical conductivity (EC), cation exchange capacity (CEC), and biological activities, including those of bacteria, fungi, and enzymes. The following provides a brief overview of how the addition of MB as a soil amendment affects soil quality. i Soil pH Section title: Effects of modified biochar on soil attributes Educational score: 4.24566650390625 Domain: biomedical Document type: Study Language: en The presence of hydrogen (H + ) and aluminum (Al 3+ ) ions in the soil exchangeable sites causes acidity, severely affecting crop yield . Pristine biochar is primarily alkaline in nature . The pyrolysis temperature (> 400 ℃) produced biochar with alkaline pH . When applied to soil, organic compounds on the biochar surface will dissolve in water entering the pore spaces, increasing soil pH . Also, biochar increases the sorption of nutrients and decreases acidity in acidic soils . However, the effectiveness of biochar in changing soil pH in acidic soils depends on the composition, properties of feedstock, and pyrolysis temperature . Thus, several modifications of biochar have been developed. The activation of rice hull biochar by immersing with dimethyl dithiocarbamate sodium solution effectively decreased pH from 10.28 to 6.53 and improved soil properties . The application of Fe-MB in Cd-contaminated soils slightly increased pH units from 7.83 to 7.93 and helped to immobilize Cd in soil . In the case of red soils, the manganese-oxide-MB increased soil pH by 1.4 units while only 0.4 units increased in pristine biochar, thus preventing acidification in red soils . On the other hand, the pH of As-contaminated paddy soils (pH 7.12) were markedly decreased by Fe–Mn MB by around 0.75–1.16 units compared to the control . Similarly, It was observed that soil resistance to acidity was enhanced through the application of HNO 3 /H 2 SO 4 -MB . Furthermore, thiourea-modified poplar-bark biochar was applied to Cd-contaminated soil, resulting in a 17% increase in soil pH as compared to the control, which led to an increase in base cations in the soil . In multi-polluted soils, the magnetic biochar derived from eucalyptus wood and poultry litter increases soil-surged pH by 0.2–0.3 units . Likewise, the porous magnetic biochar from wheat straw was added to the soil and increased soil pH by approximately 6% . But in calcareous soils, steam-AB (acidic biochar) effectively decreases soil pH by 0.2–0.4 units , while in As-contaminated soil, Ca-MB causes an increase in pH . Section title: Effects of modified biochar on soil attributes Educational score: 4.2013750076293945 Domain: biomedical Document type: Study Language: en In contrast, rice straw MB with a 1:1 mixture of HNO 3 /H 2 SO 4 and 15% H 2 O 2 effectively improved pH buffering capacity and resistance to soil acidification compared to HCl-treated and unmodified biochar. The enhanced resistance was attributed to surface functional groups that increased soil resistance to acidification by generating protonation of organic anions, which retarded the decline in soil pH. However, HNO 3 /H 2 SO 4 MB showed a higher number of carboxyl functional groups compared to the 15% H 2 O 2 -modified biochar, resulting in greater resistance to soil acidification. The application of HNO 3 /H 2 SO 4 MB in paddy soil increased pH after wet-dry cycles, suggesting that this modification is an effective solution for remediating acidic soils. The underlying mechanism involves weak acid functional groups on the biochar surface that exist as organic anions in alkaline and neutral soils. Under acidic conditions, these anions protonate with H + and convert to neutral molecules, inhibiting soil acidification and preventing a decline in soil pH , Section title: Effects of modified biochar on soil attributes Educational score: 2.1359426975250244 Domain: other Document type: Study Language: en Furthermore, Yu et al. found that soil pH increased with the application of 4% Mn oxide-MB. Similar results were observed with soil amendments using coconut shell and carrot pulp biochars modified by 8% thiourea . Other studies also showed increased soil pH with the application of 3% iron-zinc oxide composite-modified corn straw biochar , 2% Fe-modified biochar , 0.6% Brassica napus biochar-UV , and 0.6% Lolium perenne biochar-UV . ii. Soil moisture Section title: Effects of modified biochar on soil attributes Educational score: 4.018986701965332 Domain: biomedical Document type: Study Language: en Biochar application with a high surface area increases pore space and enhances soil moisture, which helps boost water retention capacity. Applying P-laden biochar considerably increased soil moisture by 93% over ordinary biochar when applied to acidic sandy soil planted with lettuce and improved seed germination and higher yield . Besides, soil moisture is enhanced by the EB derived from wood, switchgrass, and swine manure . It is claimed that nano-biochar contains larger pores and increases the number of small pores. Thus, it could increase the soil moisture content more than pristine biochar . Nano-biochar application enhanced soil water infiltration and soil moisture content . Similarly, nano-biochar was found to decrease soil water loss due to high surface area . Another, AB from the microwave catalytic process also increases water holding capacity by 98% more than ordinary biochar due to higher porosity, which shows a high correlation between WHC and micropore area . Section title: Effects of modified biochar on soil attributes Educational score: 2.574535846710205 Domain: other Document type: Study Language: en In another study on composite-MB, particle-sized biochar, and acidified biochar, it was found that all these modifications enhanced the soil water-stable aggregate contents. Specifically, acid-modified biochar at the 0–15 cm soil layer increased soil–water aggregate content by 1.45–1.80 times compared to pristine biochar, while also enhancing soil moisture content and infiltration rate . Section title: Effects of modified biochar on soil attributes Educational score: 3.7876527309417725 Domain: biomedical Document type: Study Language: en Similarly, An et al. studied biochar made from peach shells and pig manure, modified with H 3 PO 4 and KOH, and applied in four dosages (0%, 2%, 3%, and 8%). They found that H 3 PO 4 -modified biochar had superior water retention compared to KOH-modified and pristine biochar, while KOH modification reduced the hydraulic functional groups on the biochar surface. Pig manure biochar demonstrated higher crack suppression intensity than that of other functionally activated biochars. However, the study generally recommended a 5–8% dosage for enhancing water retention and minimizing cracks . iii. Dosage of application Section title: Effects of modified biochar on soil attributes Educational score: 4.148951530456543 Domain: biomedical Document type: Study Language: en The majority of biochar studies focused on application rates between 5 and 50 tons ha −1 , resulting in increased crop yield and soil properties and remediating pollutants in soil . However, this is not applicable in some cropping systems due to the high cost of production and transportation . However, several studies reported that biochar modification and application to the soil at certain rates effectively improve soil characteristics . Magnesium-oxide-derived biochar applied to saline rice paddy soils at 4.5 Mg ha −1 increases rice yields and adsorbs more phosphates . Similarly, applying Mn-oxide-MB at an increasing rate (0.5%, 1%, and 2% wt/wt) surged rice biomass and decreased As concentration in the root and rice grains compared to conventional biochar . In a similar investigation, the application of 1% magnesium-impregnated biochar to soil (wt/wt) increased available P content in the surface soil by around 50% . On the other hand, Fe-MB applied to saline paddy soil at 4.5 Mg ha −1 increased P adsorption via co-precipitation of P to iron oxides, thus increasing P availability by 79–90% over control . The yield of Cd and As-contaminated rice enhanced by Goethite-MB at the rate of (0.5%, 1.0%, and 1.5% wt/wt), the shoot biomass and root biomass increased around 56–88% and 55–98%, respectively. Also, goethite-MB decreases Cd and As concentration in rice tissues, improves photosynthesis capacity, and reduces oxidative stress . Likewise, acidified biochar derived from various raw materials, including rice husk, sugarcane-bagasse, and wheat straw, applied in the soil at 1.5% wt/wt, increased plant nutrient uptake and biomass by around 40 and 30%, respectively . Nano-biochar applied to salt-affected soils at different rates (0, 0.10, 0.20, and 0.50% wt/wt) increased P adsorption capacity . In another study, it was observed that nano-Fe-MB applied to soil at 0%, 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% wt/wt concentrations reduced soil pH, Cd concentration and enhanced soil CEC. The application of lower rates (0.2–0.4%) of nano-Fe-MB effectively decreased Cd toxicity in the soil and rice. However, high nano-iron-MB application rates (0.8–1.6%) stimulated Cd toxicity in leaves. Thus, finding the optimum application rates should be taken into consideration to avoid risk and toxicity . Nano-hydroxyapatite applied at different levels (1%, 5%, 10%, and 20%) in Pb-contaminated soils effectively immobilized Pb by around 44–57% after 28 days of incubation, effectively decreasing Pb toxicity in soils and accumulation in plants . iv. The ratio of functional material saturation Section title: Effects of modified biochar on soil attributes Educational score: 4.244823455810547 Domain: biomedical Document type: Study Language: en The ratio of functional material to modify biochar was one of the primary gauges for the adsorption of pollutants . Biochar activation was done by soaking raw biochar in solution (30% H 2 O 2 , 1 M HCl, and 1 M KOH) (1:100 ratio) for 24 h to effectively adsorb Cr (VI). The ratio of Fe to nano-Fe-modified-biochar was 19.5%, effectively improving soil properties (CEC) and reducing Cd toxicity . Similarly, Fe and Al-MB, at the ratio of 1 mol L −1 in FeCl 3 and AlCl 3 , effectively increased soil pH from 6.93 to 7.30 and enhanced P retention capacity . Furthermore, magnetic biochar prepared by mixing biomass with a solution containing (a 1:1 molar ratio of FeCl 2 and FeCl 3 ) effectively remediates soil and adsorbed heavy metals, including As, Cd, and Pb . In a recent study, Mg–Al impregnated biochar at 1:20 g ml −1 (solid to liquid ratio) was observed to be adequate in adsorbing phosphate in the soil and contained a higher amount of oxygen functional groups (MgO and AlO) as compared to pristine biochar . Similarly, MB nanoparticles exhibited a maximum adsorption capacity of 147 mg g −1 , significantly higher than the 67.8 mg g −1 capacity of unmodified biochar . This enhancement is attributed to the nanoparticles increasing the surface area and the number of functional groups on the MB surface. Moreover, KOH modification of biochar resulted in a substantial increase (approximately 2.4 times) in specific surface area and more than a 50% improvement in the adsorption capacity for Cd 2+ and Cu 2+ ions. Specifically, pristine biochar had a specific surface area of 189 m 2 g −1 , whereas KOH-MB had a surface area of 455 m 2 g −1 . The Cd 2+ adsorption capacity of pristine biochar was recorded as 4.48 mg g −1 , while KOH-treated biochar achieved a capacity of 6.81 mg g −1 , representing a 50.7% significant increase. However, the Cu 2+ adsorption capacity of unmodified biochar was 2.64 mg g −1 , whereas the KOH-modified biochar showed a significantly enhanced capacity of 4.03 mg g −1 . v. Soil types Section title: Effects of modified biochar on soil attributes Educational score: 4.101061820983887 Domain: biomedical Document type: Study Language: en The physicochemical properties of soil, including texture, structure, pH, and organic matter content, can influence the interactions between MB and soil, consequently affecting the availability and mobility of nutrients and contaminants. . It is worth noting that sandy soils with low CEC and organic matter content may have limited capacity for MB adsorption and nutrient retention. This, in turn, leads to an increased adsorption of MB and an improvement in nutrient retention . MB also increases the presence of organic matter. For instance, Kun et al. found a significant increase in soil C/N ratios and soil organic carbon after the application of Cd-binding biochar. Furthermore, observed a higher accumulation of soil organic matter (SOM) and organic carbon with the application of rice husk biochar modified with NaOH, HNO 3 , and dimethyl dithiocarbamate sodium (3% w/w). Section title: Effects of modified biochar on soil attributes Educational score: 4.119503974914551 Domain: biomedical Document type: Study Language: en Similarly, Moradi and Karimi noted increased SOM and organic carbon with Fe-modified biochar (2% w/w). Higher organic matter was also observed with the application of 2% (w/w) Fe–Mn biochar , 1% (w/w) S-biochar , 1% (w/w) S-Fe biochar, 3% (w/w) , iron-modified biochar, 8% (w/w) thiourea-modified biochar , 8% (w/w) carrot pulp biochar, and 3% (w/w) iron-zinc oxide composite modified corn straw biochar, compared to pristine biochar . This variation can be attributed to the slower decomposition of biochar depending on the soil type. The formation of soil aggregates or organo-mineral complexes provides substantial physical protection to SOM, potentially preventing its decomposition. Additionally, the temperature sensitivity varying with soil type limits short-term decomposer access to SOM, while the majority of decomposition is carried out by slower microbial metabolism . For instance, in a study by Feng , it was observed that the temperature sensitivities of biochar vary in soils with different textures and mineralogy. The temperature coefficient ( Q 10) values of biochars ranged from 1.93 to 2.20 in Oxisols and from 2.74 to 2.77 in Vertisols, within a temperature range of 20–40 °C. Additionally, the presence of biochar was found to alter the Q 10 values of native SOM as well, depending on the soil type . Section title: Future prospective Educational score: 4.040950298309326 Domain: biomedical Document type: Review Language: en Following the advancements and findings outlined in earlier sections, future research on MB should prioritize several key areas to address existing gaps and enhance our understanding. These research efforts can be categorized into four main segments. However, to achieve optimum results, collaborative efforts among experts from different domains are strongly recommended. Analytical advancement Developing Advanced Techniques : Employ more sophisticated techniques such as Pyrolysis Gas Chromatography-Mass Spectrometry (Py-GC–MS) and Thermogravimetric-Fourier Transform Infrared Spectroscopy-Mass Spectrometry (TG-FTIR-MS) to elucidate biochar formation mechanisms more accurately. Advanced Spectroscopy : Apply advanced spectroscopic methods to gain deeper insights into the functionalization of MB, allowing for better control over functional groups and porosity. Integrated Approaches : Use a combination of unique spectroscopic investigations and theoretical modeling to enhance the understanding of factors impacting biochar efficiency after soil amendment. Future perspectives in fundamental and material research Mechanism Investigation : Explore the mechanisms behind changes in biochar properties due to different pyrolysis conditions or modification procedures. Prioritize sustainable feedstock materials and their functionalization for specific contaminants to promote a green and sustainable environment. Synergistic Integration : Investigate the potential for synergistic integration with other treatment modalities, such as combining MB with biofilters, to enhance biochar's adsorption capabilities and address environmental challenges. Section title: Emerging environmental research concerns Educational score: 4.25511360168457 Domain: biomedical Document type: Study Language: en Regeneration Processes : As biochar research advances, it brings forth new challenges and dilemmas. A primary concern revolves around regeneration processes. Addressing how to efficiently desorb pollutants adsorbed on biochar for subsequent safe treatment and optimizing the recycling of the adsorbed biochar stands as paramount issues requiring meticulous consideration. Environmental Risks : A critical aspect under scrutiny is the risk of secondary pollution arising from MB. For instance, there is a pertinent question regarding the possible interaction of metal-MB with other environmental compounds following its application in soil and leaking into groundwater. Understanding the possibility of antagonistic effects with different compounds and developing effective methods for separating treated biochar from soil and groundwater are pressing issues that demand immediate attention in future research endeavors. Future research in aging and stability Long-Term Effects : Investigating the long-term effects of MB on soil functions and its behavior across diverse soil types necessitates immediate attention. A recent study illustrated the direct influence of MB on soil biological communities' composition and abundance, as well as affects the retention of applied pesticides . Consequently, weed control in MB-amended soils may pose challenges, as the efficacy of preemergence herbicides could diminish. Environmental Behavior: MB proved to facilitate the formation of soil aggregates, enhance the physical protection of organic carbon, and increase yield production, with other positive environmental impacts such as the decrease in methane and gross greenhouse gas emissions. However, these initial positive effects might shift to negative over time, necessitating attention to the long-term environmental behavior of MB. It is particularly crucial to investigate how biochar interacts with minerals and how such interactions affect the performance of soil and water remediation over short-term and long-term aging. Addressing these issues in future research is imperative for a comprehensive understanding of MB's role and impact on soil. Simulated Aging Methods : There is a need to develop simulated aging methods that integrate multiple artificial aging processes. Specifically, considering the aging time scale in natural environments, it is crucial to quantitatively explore response models of MB properties using various artificial aging methods. This approach will enhance our understanding of how biochar evolves over time under environmental conditions and improve the accuracy of predictions regarding its behavior and efficacy in practical soil applications and its implications for different crop systems. Geochemical Behavior : In the context of pollutant management by MB, there exists a pressing need for further exploration into the geochemical behavior of emerging contaminants under long-term application MB. Understanding how MB aging interacts with and influences the fate of emerging contaminants across diverse environmental contexts is crucial for devising effective pollutant remediation and management strategies. For instance, investigating potential scenarios such as the movement of MB to groundwater and the release of metals in the case of metal modification. However, the impacts of such interactions are contingent upon soil types, with sandy soils often exhibiting more significant benefits compared to others . As a result, there is an urgent need for extensive research on the long-term effects of MB across various soil types. Section title: Emerging environmental research concerns Educational score: 2.3235058784484863 Domain: biomedical Document type: Other Language: en In summary, focusing on these future research areas will advance our understanding of MB and its applications. An integrated and collaborative approach will be essential for achieving comprehensive and impactful results. Section title: Conclusion Educational score: 3.632262706756592 Domain: other Document type: Review Language: en In conclusion, this article explores the physicochemical characteristics of biochar altered through various techniques, emphasizing the significance of comprehending the impact of these alterations on biochar properties. This insight will assist readers in discerning effective methods to modify biochar for specific applications. Our assessment suggests that MBs have significant potential for improving soil quality and health, and mitigating greenhouse gases. Furthermore, environmentally-friendly modifications can enhance energy and carbon storage in soils. Additionally, this review will offer comprehensive insights into advanced analytical techniques developed to analyze modifications necessary prior to application, enabling precise targeting of specific objectives. However, further investigation is required to analyze the relationships between material composition, structure, and energy storage. Overall, this article contributes to our understanding of the potential of MB as a versatile and sustainable material with significant environmental and economic benefits. Section title: Outlook Educational score: 3.702572822570801 Domain: biomedical Document type: Review Language: en This comprehensive review thoroughly explores the recent advances in utilizing Modified biochar (MB), specifically in soils. Beyond mere synthesis, it delves into the evolved physicochemical characteristics of MB, providing invaluable insights into its efficacy and limitations. Indeed, comprehending the unique properties endowed by each modifying agent is paramount, as they directly shape the characteristics of the final product. Therefore, it is imperative to fully grasp the attributes of both MB and the modifying agent prior to production, enabling targeted applications within soil environments. Section title: Outlook Educational score: 3.6292216777801514 Domain: biomedical Document type: Review Language: en However, in the rapidly advancing world, it is essential to ascertain the exact nature and properties of processed MB. Hence, our review underscores the significance of embracing advanced analytical methodologies to characterize modified biochar and gauge its effectiveness precisely. By doing so, we aim to shed light on the crucial role these techniques play in ensuring biochar quality and performance in modern applications. Furthermore, this paper contains a comprehensive discussion of the mechanisms behind the factors influencing the efficiency of MB post-soil application. Section title: Outlook Educational score: 4.010374546051025 Domain: biomedical Document type: Study Language: en Additionally, we have highlighted the need for future research to explore the mechanisms behind alterations in biochar properties due to different modifications. Our future research perspective section is delineated into four segments. Firstly, analytical advancement advocates for leveraging sophisticated techniques, such as Pyrolysis Gas Chromatography-Mass Spectrometry (Py-GC–MS) and Thermogravimetric-Fourier Transform Infrared Spectroscopy-Mass Spectrometry (TG-FTIR-MS) to deepen our comprehension of biochar formation mechanisms. Additionally, it underscores the significance of advanced spectroscopic methods in elucidating modified biochar functionalization for precise control over functional groups and porosity. Secondly, future research in fundamental and material research underscores the importance of synergistically integrating MB with other treatment modalities, and investigating the mechanisms underlying changes in biochar properties resulting from modification procedures. Section title: Outlook Educational score: 2.88991641998291 Domain: other Document type: Study Language: en Moreover, concerns regarding risks associated with MB are pointed out in the environmental research section, such as the risk of secondary pollution by potential leakage into groundwater after application, the possibility of antagonistic effects, and the development of new regeneration processes to enhance pollutant absorption efficiency. Lastly, the roadmap for aging and stability future research delves into the necessity of focusing on the long-term effects of MB on soil functions and its behavior across diverse soil types. This entails comprehensively understanding MB role and impact on soil by developing simulated aging methods that integrate multiple artificial aging processes. This will enhance the accuracy of predictions concerning MB's behavior and efficacy in practical soil applications and its implications for different crop systems. | Other | other | en | 0.999999 |
PMC11698997 | Section title: Background Educational score: 3.192659616470337 Domain: biomedical Document type: Other Language: en Objective structured clinical examinations (OSCEs) are widely used in Health Professions’ Education globally as a tool to test specific skills relevant to clinical practice. Whilst in some countries they have been used for decades, in others they have been introduced relatively recently. In the UK for example, the implementation of integrated OSCE stations where multiple tasks are combined in a single practical station is commonplace . In comparison, for many educational programmes and institutions elsewhere in the world, this integrated OSCE style is still novel and faculty members are unlikely to be familiar with the operational approach to this style compared to the more traditional long case or viva styles of practical assessment . Section title: Background Educational score: 3.525118112564087 Domain: biomedical Document type: Other Language: en International partnerships in medical education are an increasingly popular tool to enable new and existing organisations to raise standards with assessment being a particularly important area in these partnerships. The UCL Medical School’s Centre for International Medical Education Collaborations (CIMEC) works collaboratively with institutions around the world to develop tailored medical educational programmes by co-developing and embedding high-quality education and assessments . Collaborating medical institutions are located in various countries and are often at the early stages of developing and establishing a medical educational curriculum and assessment structure. Thus, they often value the knowledge and expertise that the UCL Medical School CIMEC team can provide. All collaborations aim to co-create high-quality, sustainable and locally customised education programmes . Assistance with the development of assessments has encompassed various areas of the partnership both in assessment design and delivery of high-quality written and practical assessment items including OSCEs, where feedback and experiential knowledge are often highly valued by collaborators . Section title: Background Educational score: 1.6446001529693604 Domain: other Document type: Other Language: en Over the past 7 years, Newgiza University (NGU) and UCL have worked in an international academic collaboration in the development and delivery of its undergraduate medicine, dental and pharmacy programmes. During this time, senior faculty and staff from UCL have worked with NGU, to strategically plan and organise the new programmes by setting up appropriate infrastructure, developing curricula and resources and ensuring education quality assurance. This enduring partnership has been strengthened by collaboration between faculties . Providing feedback is a crucial step in the development of an OSCE station for quality assurance and the peer-review process can be helpful in this . Together with NGU, UCL have reflected on processes and challenged their existing models of assessment feedback. Section title: Background Educational score: 1.7607777118682861 Domain: other Document type: Other Language: en Faculty development has been shown to increase OSCE item quality and the collaboration between UCL and NGU has always worked towards strong quality assurance measures. Historically, when developing OSCE assessment material with NGU, station authors from NGU would draft and submit OSCE stations to the UCL team based on previously delivered faculty development sessions. The UCL academic team would subsequently provide tailored review, feedback and quality assurance for each station before it was returned electronically to the faculty members to make amendments and finalise the draft for delivery in the examinations. Feedback would be taken at the discretion of the NGU station authors and leadership teams and implemented according to their needs, with little further dialogue between author and reviewer. Section title: Background Educational score: 3.1019585132598877 Domain: biomedical Document type: Study Language: en NGU and UCL worked collaboratively to identify some of the key challenges posed by this methodology. Firstly, the feedback was not always timely as the method of writing OSCE stations; their dissemination for review and duration for turn around of feedback can be time consuming. Moreover, feedback provided was unidirectional in delivery, which we know is certainly a historically conceptualised process in medical education , and maybe perceived as less effective in the spirit of collaboration. This approach has also posed difficulties for the UCL team to confirm whether the feedback has been fully understood or can be readily applied to enable the changes to be implemented accurately. This lack of a two-way dialogue in provision of feedback also failed to provide NGU with an opportunity to voice any adaptations that they required to follow through with advice on an OSCE station to make it relevant to the local community. For example, there may be differences in the availability of certain resources such as specific prosthetic models or access to simulated patients with relevant training to deliver the OSCE station. Section title: Background Educational score: 1.1650582551956177 Domain: other Document type: Other Language: en As mentioned, the use of integrated OSCE stations remains a novel approach to assessment for some nations, but global partnerships such as that between NGU and UCL work to continually collaborate and produce high-quality assessment items. This difference in the traditional model of writing OSCE stations has heightened the need for novel approaches to improve the feedback provided and greater two-way dialogue between UCL and NGU. Section title: Activity Educational score: 1.3754607439041138 Domain: other Document type: Other Language: en To improve upon this, a synchronous workshop was co-designed by UCL and NGU teams, which adopted a new teaching and learning approach of providing real-time feedback on assessment materials as a second ‘layer’ of feedback especially for the high stakes’ final year examination. Section title: Activity Educational score: 2.046813726425171 Domain: biomedical Document type: Other Language: en A live online workshop was piloted providing a forum for discussion about the pre-submitted OSCE stations, which was attended by NGU and UCL faculty members (authors and reviewers). The live workshop utilised the model from previous collaborations and consisted of four subgroups in total . Small groups with numbers limited to a maximum of six participants per group provided a platform for a two-way discussion about each OSCE station to be discussed. Groups remained consistent throughout the workshop to enhance rapport building. Faculty were assigned to groups based on their areas of expertise including their subspecialty. Fig. 1 Original feedback model compared to live synchronous feedback model Section title: Activity Educational score: 1.6504920721054077 Domain: other Document type: Other Language: en Both teams prepared for the session by reviewing the OSCE stations and making notes where appropriate in advance. The workshop duration was 2 hours based on previous international workshops and feedback. A total of four OSCE stations were discussed in each subgroup where an open dialogue allowed an opportunity for opinions and debate to occur. This workshop model adopted a more collaborative approach and reduced the paternalistic elements of the previous feedback model adopted. Real-time edits were made on-screen by UCL facilitators with agreement from the NGU team. Feedback forms were disseminated after the workshop to the NGU faculty members to evaluate the workshop and its sustainability as a long-term adaptation to feedback delivery. Section title: Results Educational score: 2.2348227500915527 Domain: other Document type: Study Language: en Feedback was sought to evaluate the utility, efficiency and reception of the synchronous workshop in a mix of verbal and written formats and was resoundingly positive . All participants identified the online session as more useful than written feedback alone, with 83% agreeing completely. All comments indicated that the synchronous workshop allowed for deeper discussion about OSCE format, timing within the station and logistics and practicalities of the station. Most participants also appreciated the process of live edits being made by the facilitator during the session as they felt that this better addressed their needs as a faculty and because it meant that a final version of the assessment was available by the end of the session. It also helped station authors to understand the rationale for, motivations behind, and context of, the reviewers’ feedback decisions. Future recommendations from NGU have included having more time allocated for discussion and a greater focus on exploring the challenges of developing OSCE stations and how these can be mitigated. Fig. 2 Evaluation feedback Section title: Results Educational score: 1.0817188024520874 Domain: other Document type: Other Language: en The findings of this feedback further reiterate that international educational partnerships are relational and greatly dependant on care and communication between partners, whereby the key to ensuring successful enduring partnerships lies in maintaining cross cultural relationships by employing humility, reflexivity and cognitive flexibility . Section title: Results Educational score: 1.8053022623062134 Domain: other Document type: Other Language: en Moreover, our findings fit with the growing literature that feedback is a multifaceted phenomenon that is far more fluid in its concept than has traditionally been believed. Ajjawi et al. describe the concept of feedback as a co-constructive interaction that is inherently a fragile non-prescriptive process. Our experience has been consistent with this approach as feedback across partnerships often requires us to have difficult conversations in order to leverage change . This can only be achieved where partnerships are strong and there is mutual respect and understanding. Our work also highlights that we must acknowledge the human elements of feedback literacy , which play a significant role in co-creation of educational and assessment material. Section title: Discussion Educational score: 1.1632485389709473 Domain: other Document type: Other Language: en This co-designed OSCE feedback model, which harnesses the benefits of two-way dialogue, has led to an evolution in our joint approach to providing feedback for high-stakes assessment items in this ongoing partnership, especially for quality assuring OSCEs including fewer queries regarding stations. Section title: Discussion Educational score: 1.0634065866470337 Domain: other Document type: Other Language: en We feel that this model may enable other partnering institutions to follow suit and will promote ongoing capacity building for both teams. Section title: Discussion Educational score: 1.0494953393936157 Domain: other Document type: Other Language: en We hope to apply this synchronous feedback model to other assessments amongst our international partners when reviewing both written and practical assessments. Moreover, we believe that the scope of this collaborative model can also be further adapted to utilise within curriculum development review activities in the future. | Other | biomedical | en | 0.999996 |
PMC11699018 | Section title: Introduction Educational score: 3.7701570987701416 Domain: biomedical Document type: Other Language: en Globalization leads to an increasing number of students studying and working abroad, necessitating proficiency in the local language for effective communication with colleagues and patients in the medical field. Medical interns face challenges in hospitals due to language barriers and ineffective communication. Fluency in Dutch is essential for international medical students in the Netherlands to effectively communicate with Dutch-speaking patients and colleagues in their future careers. Accordingly, courses teaching medical Dutch need to be introduced, and course designs needs to support efficient medical second language (L2) learning. Although medical simulations enhance students’ proficiency, having native speakers as learning partners offers experiential examples, feedback, and corrections for sentences and phrases. These approaches aim to equip students with the language skills necessary for successful medical practice in a Dutch-speaking environment . Section title: Introduction Educational score: 3.5928916931152344 Domain: biomedical Document type: Study Language: en In medical L2 learning, study partners are often nonnative peers rather than native speakers of the language . In this study, the term nonnative indicates a person who is not a native speaker of the language in which the medical terms are studied. To assess the effects of nonnative or native study partners on language learning, we conducted a comparative study examining students’ levels of confidence in their language skills, their collaborative strategies, and learning experiences in homogeneous (study pairs of nonnative students) and mixed (study pairs comprising of a native and a nonnative student) groups. Varying proficiency levels between learning partners can result in differential impacts on students, and our study aimed to address this issue . Section title: Introduction Educational score: 1.7335363626480103 Domain: other Document type: Other Language: en The fundamental question was which type of partner would optimally foster collaboration and language learning . The medical Dutch course involved both native and nonnative Dutch speakers, to explore the potential impact of differences between nonnative and native speakers on language learning outcomes. Section title: Introduction Educational score: 1.201793909072876 Domain: other Document type: Other Language: en Pairing with a native speaker may enhance fluency and pronunciation, boosting students’ confidence in speaking like a native partner . Moreover, native partners can offer comprehensive language feedback, assisting nonnative students in identifying areas for improvement and boosting their confidence in L2 proficiency . Conversely, nonnative students may find it easier to relate to and receive empathetic support and encouragement from other nonnative students . They can also share experiences and overcome language learning challenges at a similar pace, creating a positive learning experience with their partners [ 11 – 13 ]. Section title: Introduction Educational score: 4.073558807373047 Domain: biomedical Document type: Study Language: en Drawing from Kolb’s experiential learning theory , and considering relevant literature, we incorporated simulated consultations into the medical Dutch course to compare the effects of learning partners . Kolb’s experiential learning theory proposes a learning cycle involving concrete experience, reflective observation, abstract conceptualization, and active experimentation . Simulated patient consultations have proven effective for medical consultation and L2 learning, aligning with concrete experience and active experimentation. Pairing students for consultations fosters reflective observation and abstract conceptualization, offering valuable benefits through observational feedback and deep thinking [ 17 – 20 ]. Integrating these course design methods offers students’ opportunities to engage in real-life scenarios and reflective discussions with their partners. This fosters improved communication skills, language learning confidence, and collaborative benefits during consultations, enhancing professionalism in using medical Dutch [ 21 – 23 ]. Fig. 1 Model of Kolb’s experiential learning Section title: Introduction Educational score: 2.871835708618164 Domain: biomedical Document type: Study Language: en Research questions were formulated based on the preceding discussion: (1) Does the confidence in medical Dutch significantly differ between students learning in mixed and homogeneous groups? It was hypothesized that students paired with native Dutch-speaking partners would display higher confidence than those paired with nonnative partners. (2) Are there variations in perceived collaborative strategies and learning experiences between mixed and homogeneous groups? The hypothesis suggested that the mixed group, where nonnative students were paired with native partners, would be more open to feedback and exhibit a feedback-centered learning experience, while the homogeneous group might establish stronger partner relationships with closer bonds or partnership between nonnative partners. Section title: Design and Participants Educational score: 4.104074001312256 Domain: biomedical Document type: Study Language: en This mixed-methods study utilized a pre- and post-test comparative design with 12 third-year international medical students (mean age = 22.3 years, range from 20 to 28 years) enrolled in a medical Dutch course at Maastricht University . Four exceptionally proficient native Dutch-speaking students, exempted from the course based on a rigorous language evaluation, were invited back as native partners to assist the medical Dutch learning of the other students. The mixed group consisted of these four native partners randomly paired with four of the 12 students, while the remaining eight students formed four homogeneous groups. All students attained a proficiency level of at least B2 in Dutch, according to the Common European Framework of Reference for Languages (CEFR), which signifies their ability to engage in intricate social dialogues, comprehend and analyze sophisticated Dutch texts and books, and articulate complex thoughts and viewpoints in writing. Level B2 is the standard for foreign diploma holders who aspire to pursue higher professional education in the Netherlands. Additionally, the course was conducted in Dutch, and they possessed a minimum of 2 years of practical experience in simulated patient consultation sessions conducted in English, which allowed them to focus on Dutch language learning during the course. The nonnative participants were German (4), French (2), Spanish (2), Finish (1), Irish (1), Romanian (1), and Italian (10) students. Fig. 2 Background information on the quasi-experimental groups. Native facilitators are indicated in blue, and nonnative participants in green. Gender, student number, and nationality are indicated in the image. Mean age in both groups was similar (22 years) Section title: Design and Participants Educational score: 1.4167965650558472 Domain: other Document type: Other Language: en Participants were compensated with 20 euros per hour for their additional time spent cooperating with the researcher, which included completing questionnaires and participating in interviews after the course. Section title: Course Structure and Pairing of Students Educational score: 2.391770124435425 Domain: biomedical Document type: Other Language: en The 15-week program comprised 2-h Dutch medical teaching sessions each week, covering advanced medical terminology, grammar, consultation structures, and example videos. Additionally, there were three 30-min simulated patient consultation (SPC) sessions in the 8th, 11th, and 14th weeks. Each student had a designated study partner for these sessions, as shown in Fig. 3 . Fig. 3 Simulated patient consultation component Section title: Course Structure and Pairing of Students Educational score: 2.0690343379974365 Domain: biomedical Document type: Study Language: en During the SPC sessions, each member of a study pair could choose to be either the student-doctor or student-observer . After the session, student-doctors received feedback from their student-observers in a debriefing session . Roles were then switched, and steps 2 and 3 were repeated. In total, each student acted as a student-doctor and student-observer three times during the SPCs. Section title: Need Satisfaction Competence Scale in Pre- and Post-tests Educational score: 2.8140180110931396 Domain: biomedical Document type: Study Language: en The need satisfaction competence scale (NSCS) was used in both pre- and post-tests to assess students’ confidence in learning medical Dutch as their L2. Each item was rated on a 7-point Likert scale, with responses ranging from 1 (strongly disagree) to 7 (strongly agree), i.e., “In my studies, I feel highly effective at what I do.” (available as Supplementary Digital Appendix 1 ). The Cronbach’s α reliability coefficient for the NSCS was 0.81. Section title: Perceived Collaborative Strategies Educational score: 1.7212117910385132 Domain: other Document type: Study Language: en To collect information about collaborative strategies, students were individually interviewed. The interviews were aimed at understanding their opinions about their partner’s proficiency in medical Dutch. Participants were asked questions like “How would you describe your partner’s ability to use medical Dutch?” Furthermore, students were asked to share the specific methods their partners used to support their language learning. Questions like “What strategies do you and your partner use to help each other?” were posed. Section title: Individual Semi-structured Interviews Educational score: 2.1277449131011963 Domain: biomedical Document type: Study Language: en To reduce the likelihood of social desirability bias , participants were invited individually to the semi-structured interviews. Each interview guide included questions related to the four components of the study: Learning atmosphere (e.g., “Can you describe the atmosphere when your partner was with you during the course?”), Partner support (e.g. “How did you feel about the progress of your consultation ability in relation to your partner?”), Confidence (e.g., “Can you recall when you felt confident in medical Dutch and which part of the medical Dutch course contributed to this feeling?”), Language learning (e.g., “How did your partner help you with learning medical Dutch?”). (Ava for the full interview guide) Section title: Procedure Educational score: 1.6963344812393188 Domain: other Document type: Study Language: en A pre-test scale was used to assess the initial level of confidence among students after the first week of the course. At the end of the course, students completed the post-test questionnaire and participated in the interview session the following week. Section title: Data Analysis Educational score: 3.5242233276367188 Domain: other Document type: Study Language: en The individual semi-structured interviews underwent content and thematic analyses to uncover the collaborative strategies and learning experiences underlying both the mixed and homogenous groups . The collaborative strategies were independently identified by two researchers from the field of education (H.Y. and M.A.) and were summarized into six categories, available as supplemental digital appendix 4 . Two researchers (H.Y. and F.J.) independently coded the interview data, compared and discussed the resulting codes and themes, and resolved any discrepancies in two team meetings. The thematic findings underwent a code co-occurrence analysis, which allowed the generation of nodes and edges for subsequent network analysis [ 27 – 29 ]. The network analysis was based on data from the code co-occurrence matrix and coefficients of codes and was available as supplemental digital appendix 3 . A force-directed graph was provided to visualize the structure of the networks. Section title: Results Educational score: 2.1860854625701904 Domain: biomedical Document type: Study Language: en Research question 1 was aimed at comparing the difference in confidence levels between participants in the mixed and homogeneous groups. The findings from the pre- and post-test NSCS questionnaires provided evidence to support evidence addressing this research question. Section title: Students’ Confidence in Learning Medical Dutch Educational score: 4.118730545043945 Domain: biomedical Document type: Study Language: en We analyzed the NSCS results to determine the confidence of the participants in their medical Dutch at the beginning and the end of the study (Table 1 ). The Mann–Whitney U test result and the normalized gain score revealed that the confidence of the mixed group decreased marginally ( U = 3.85, Z = − 0.55, p = 0.58, r = 0.28) resulting in a small negative normalized gain (N-gain = − 10.7%, SD = 0.25; Table 1 ) while the confidence of the homogenous group improved substantially ( U = 15.50, Z = − 2.21, p = 0.03, r = 0.38) and showed a positive normalized gain (N-gain = 11.3%, SD = 0.08). Table 1 Confidence of nonnative students in the mixed and homogenous groups Confidence Mixed ( n = 4) Homogenous ( n = 8) Median IQR Median IQR Pre-test 5.53 1.33 4.67 1.41 Post-test 5.33 2.67 5.83 1.17 N-gain − 10.7% ± 0.25 (SD) 11.3% ± 0.08 (SD) Section title: Perceived Collaborative Strategies Educational score: 4.022350311279297 Domain: biomedical Document type: Study Language: en Research question 2 first investigated collaborative strategies in mixed and homogeneous groups using content analysis. Responses to the interview question “How did your partner affect your medical Dutch learning?” yielded a total of 238 responses on strategies. Among these, mixed groups reported 58 times on strategies (24% of 238), while homogeneous groups reported 180 times on strategies (76% of 238), indicating higher strategy exchange in the homogeneous groups. Available as supplemental digital appendix 4 , collaborative strategies: Language use in SPC, covering grammar and word usage during sessions. Communication skills, including tone, facial expressions, empathy, questioning style, and other communication-related aspects. Partner comparison, involving feedback or observations comparing one’s performance with their partner. Interaction and feedback, concerning the nature of feedback received, including positivity, constructiveness, warnings or criticisms, and knowledge sharing. Personal growth, referring to flexible thinking, enhanced learning effectiveness, and self-recognition of personal growth. Drawbacks, encompassing challenges like language communication difficulties, anxiety, lack of feedback, and ineffective feedback. Section title: Perceived Collaborative Strategies Educational score: 2.091867208480835 Domain: biomedical Document type: Study Language: en The radar plot in Fig. 4 visually represents the six dimensions. Both groups shared similar collaborative strategies in language use in SPC, partner comparison, and interaction and feedback. The homogenous group showed a slightly higher prevalence in communication skills, while the mixed group emphasized personal growth more. Additionally, the homogenous group exhibited a higher occurrence of drawbacks (available as Supplemental Digital Appendix 3 ). Fig. 4 Radar plot of collaborative strategies Section title: Perceived Learning Experience Educational score: 1.9091928005218506 Domain: other Document type: Study Language: en Thematic analysis was conducted to answer the second part of research question 2, namely to understand students’ learning experiences and identify potential connections between themes in the network analysis. Seven themes emerged from both mixed and homogenous groups, presented as percentages in Fig. 5 . Some themes were addressed by both groups to a similar extent, while other themes were more dominant in one group. Fig. 5 Distribution of themes in the homogenous and mixed groups in % Section title: Perceived Learning Experience Educational score: 1.9508757591247559 Domain: biomedical Document type: Study Language: en The distribution of these themes is visualized in a diagram . The three themes positive atmosphere, collaboration, and confidence showed comparable percentage of codes across both groups. In each group, two separate themes were prioritized. The homogenous group reported a higher frequency of themes related to interpersonal relationships and feedback-seekin g behaviors while the mixed group demonstrated a higher frequency of themes associated with language learning and motivation. Fig. 6 Common and prioritized themes Section title: Positive Atmosphere Educational score: 1.6815519332885742 Domain: other Document type: Study Language: en The positive atmosphere emerged as one of the most frequently mentioned themes with 38 occurrences, with highest frequencies for codes associated with positive feedback. Additionally, codes such as positive reinforcement, appreciation, and codes related to attitude were highly valued within this theme (available as Supplemental Digital Appendix 2 , Table S 1 ). Student 3 and student 6 stated the following: Section title: Positive Atmosphere Educational score: 1.0303655862808228 Domain: other Document type: Other Language: en So it’s not someone that makes you just feel all the time stressed or something like that, but like encouraging even if you are not doing so well or whatever, because obviously everyone has their own process. (student 3 from mixed group) Section title: Positive Atmosphere Educational score: 0.9546079039573669 Domain: other Document type: Other Language: en I would say that we have a good atmosphere among us, as we’re also friends outside of university. It feels friendly and respectful, and we’re always trying to help each other. We don’t make fun of each other, but we do point out areas for improvement while also acknowledging the things that are going well. That way, we stay positive and don’t get stuck on the negatives (student 6 from homogenous group). Section title: Collaboration Educational score: 2.0267879962921143 Domain: other Document type: Study Language: en The theme of collaboration encompassed the dynamic process of guiding individuals towards shared objectives, fostering cooperation and problem-solving, and promoting synergy within the group. The thematic analysis revealed codes that aligned with the collaborative strategies shown in Fig. 4 . These codes included interaction and feedback, which were mentioned 23 times. Peer support in language learning and communication was mentioned 19 times, while observations were mentioned 12 times. Other supporting codes can be found in supplemental digital appendix 2 , Table S 1 . Student 2 and student 12 expressed the following: Section title: Collaboration Educational score: 0.9790066480636597 Domain: other Document type: Other Language: en Sometimes, my peer could see certain aspects about how my talk was, or if I misuse a word or something, it can be done subconsciously so in those aspects, the observing student helped with my Dutch language. (student 2 from mixed group) Section title: Collaboration Educational score: 0.9863350987434387 Domain: other Document type: Other Language: en I think it’s really useful to track one person’s impact on the improvement through pairing up. Because right now we’re not a group of different people every time. So we can keep track and it’s a lot easier to see where we started. (student 12 from homogenous group) Section title: Confidence Educational score: 2.0656378269195557 Domain: other Document type: Study Language: en The theme of confidence emerged as a significant aspect in this study, with 27 codes identified in the homogenous group and 10 codes in the mixed group. The themes identified emphasized the positive impact of peer collaboration on boosting students’ confidence and highlighted the importance of confidence in the learning process. Specifically, confidence gained from peer collaboration was mentioned 14 times, while confidence derived from students’ improvement and success was mentioned 18 times. Furthermore, additional codes can be found in supplemental digital appendix 2 , Table S 1 . As quoted by students 11 and 2: Section title: Confidence Educational score: 0.9858941435813904 Domain: other Document type: Other Language: en It is nice to have someone who knows me and knows my level of Dutch. Because we always know that they are just there to help you, they are not like to judge you or grade you or anything, and so, yeah, it increases my confidence to have someone that I know next to me. (student 11 from homogenous group) Section title: Confidence Educational score: 1.03761625289917 Domain: other Document type: Other Language: en So now her feedback to me was always ‘you are doing good’ For that she would tell me what words I could change, how to do it better, and that was really nice and then she was always very sweet, and she made notes during my SPC, … that was helping a lot and gave me confidence. (student 2 from mixed group) Section title: Prioritized Themes of Mixed Group Educational score: 1.4034613370895386 Domain: other Document type: Study Language: en In addition to the common themes identified in both the mixed and the homogenous group , the themes of language learning and motivation were highly prioritized in the mixed group, with a higher percentage of codes on that topic reported compared to the homogenous group. Section title: Language Learning Educational score: 1.2297190427780151 Domain: other Document type: Study Language: en This theme described the effect of students supporting each other, providing feedback, and offering necessary assistance in learning Dutch. The collaborative strategies of language use in SPC and personal growth dominantly described the theme of language learning. A slight difference was found between the groups. Specifically, the code of language barriers (mentioned 7 times) highlighted the challenges that emerged from students comparing their language proficiency with native partners. It was observed that in mixed groups, the quality of feedback provided was more in-depth and constructive compared to the homogeneous group. Section title: Language Learning Educational score: 1.3813637495040894 Domain: other Document type: Study Language: en In general, in mixed groups, three codes, namely Dutch learning (mentioned 11 times), language barriers (mentioned 7 times), and language improvement (mentioned 6 times), predominantly contributed to this theme (available as Supplemental Digital Appendix 2 , Table S2 ). An example quotation from student 3 illustrated this. Section title: Language Learning Educational score: 0.9829505085945129 Domain: other Document type: Other Language: en My partner always gives me feedback when I need it. It is better to say that when it is not comfortable talks in that practice, they can then try to give feedback more on the structure of the consultation. You obviously have to understand that the different backgrounds also influence. So you try to make the best of it, obviously and still get helps from your partner. (student 3) Section title: Language Learning Educational score: 0.9896926283836365 Domain: other Document type: Other Language: en On the other hand, in homogenous groups, the focus primarily revolved around Dutch learning (mentioned 42 times) and language improvement (mentioned 10 times). Here is an example quotation from student 11. Section title: Language Learning Educational score: 0.9620458483695984 Domain: other Document type: Other Language: en Maybe student 7 and I are more on the same level because we are both German. It’s very similar to Dutch. So it’s also like we also learn it in the same in the same way. And we have the same struggles with like words that are not that similar or grammar that’s different. (Student 11) Section title: Motivation Educational score: 1.3783475160598755 Domain: other Document type: Study Language: en This theme described how students were motivated, either by external factors or through self-motivation, during the course. In the mixed group setting, the theme of motivation was predominantly supported by the presence of a native partner (mentioned 16 times, available as Supplemental Digital Appendix 2 , Table S2 ). A quotation from student 3 illustrated this aspect. Section title: Motivation Educational score: 0.9815332889556885 Domain: other Document type: Other Language: en I think even I was a bit insecure in the beginning of my medical Dutch course, and she was giving me good feedback, ‘you did fine’, ‘don’t worry, and it’s good’ and that put it into perspective and I felt a lot better afterwards. Because she know that I trust her, and all that ‘she’s good’ or when she says, ‘you are doing fine’, I believe her. (student 3) Section title: Motivation Educational score: 1.3025530576705933 Domain: other Document type: Other Language: en On the other hand, in the homogenous group, the primary code that stood out was “motivational SPC setting” (mentioned in the quotation from student 5). Section title: Motivation Educational score: 1.0580304861068726 Domain: other Document type: Other Language: en I think the patient is the main person and the most important person in that situation. I think that like the patient being that really motivates me to do a good job. And I want to make a practice for being a good doctor later. So I don’t really think about my peers being there. I just like think about the patient was there and try to do my best in and pretending I’m a doctor and they are patient. So I think that’s like my main motivation and also what I focus on. (student 5) Section title: Prioritized Themes of Homogenous Group Educational score: 1.5863677263259888 Domain: other Document type: Study Language: en In the homogenous group, the themes of interpersonal relationships and feedback-seeking behaviors had a higher reporting rate in interviews compared to the mixed group . These themes were also found in collaborative strategies; for example, partner comparison and interactive and feedback strategies were also coded in the themes of interpersonal relationships and feedback-seeking behavior. Section title: Interpersonal Relationships Educational score: 1.5633478164672852 Domain: other Document type: Study Language: en The theme of interpersonal relationships encompassed a diverse range of codes that displayed variations across different groups. Within the homogenous groups, the code of social interaction and support was mentioned 14 times. Additionally, communication skills (7 times) and friendship (7 times) emerged as important components (available as Supplemental Digital Appendix 2 , Table S2 ). Two example quotations from students 6 and 7: Section title: Interpersonal Relationships Educational score: 1.003587245941162 Domain: other Document type: Other Language: en It is nice when you have someone accompany you in the room other than just a patient. So you can always ask for time out, or at the end, they will know a bit more about our courses, like the structure and stuff that the patient doesn’t necessarily know. ... I think she has a good standard of speaking Dutch, and she can also understand most things. So I think her Dutch is the same level as mine around. (student 6) Section title: Interpersonal Relationships Educational score: 0.9804919362068176 Domain: other Document type: Other Language: en We spend time doing the SPC together; we become closer over the time…. I think it is a bonding thing if you study something together, and you learn together, and then you kind of become close. So it improves our relationship and the overall atmosphere. (student 7) Section title: Interpersonal Relationships Educational score: 1.0915099382400513 Domain: other Document type: Other Language: en In contrast, in mixed groups, one prominent factor observed was comparison, 5 times. Additionally, other codes such as comradery, sense of belonging, social norms, and pressure were mentioned 2 times across all the interviews, as highlighted in the quotation from student 4. Section title: Interpersonal Relationships Educational score: 0.9841200113296509 Domain: other Document type: Other Language: en Sometimes it can be a bit unfair when you’re all in the same class, but then someone is already on a higher level, then, we are also considering this have a beneficial effect because they already speaking good, they can constantly giving more peer feedback. (student 4) Section title: Feedback-Seeking Behavior Educational score: 1.4733566045761108 Domain: other Document type: Study Language: en The theme of feedback-seeking behaviors highlights the specific codes that are unique to different groups. In the context of homogenous groups, the importance of seeking feedback by drawing upon experiences from their collaboration was mentioned 27 times, which also overlays with collaborative strategies of interaction and feedback, as illustrated in the example quotation from student 10. Further details regarding the rest of the codes can be found in supplemental digital appendix 2 , Table S 3 . Section title: Feedback-Seeking Behavior Educational score: 1.021668553352356 Domain: other Document type: Other Language: en I think, in fact, I affected their learning in the same way, because we are just in a group together and we do exercises also together and then. We can also learn from each other’s useful tips. They can also inspire that when I see my partner has a really nice way of speaking or uses a specific phrases. Then I can also pick up on that and also incorporated into my consultation. Maybe I think that’s really nice. Also, that feedback is really useful, because sometimes I’m also not aware of certain things during the consultation. (student 10) Section title: Feedback-Seeking Behavior Educational score: 1.149346947669983 Domain: other Document type: Other Language: en Differently, in mixed groups, the prominent codes related to feedback were feedback constructiveness (5 times) and experience-based feedback (4 times), as indicated in the quotation from student 4. Section title: Feedback-Seeking Behavior Educational score: 0.9524654746055603 Domain: other Document type: Other Language: en I think if it appears to be giving feedback the way natives did, yeah, quite constructive because they’re not just saying you are good. They could really give me an example of what is not going right. They can really pinpoint it and give me the reason for it. (student 4). Section title: Network Analysis of Themes Educational score: 2.0224452018737793 Domain: other Document type: Study Language: en The thematic analysis findings led to the exclusion of language learning and motivation themes from the homogenous group, and interpersonal relationship and feedback-seeking behavior themes from the mixed group in the network analysis. These themes were considered to have less meaningful implications for each group. The code co-occurrence matrix and coefficients were then utilized to create the nodes and edges of the force-directed graph, illustrating the codes . Fig. 7 Force-directed network of themes for the homogenous group ( A ) and mixed group ( B ) Section title: Network Analysis of Themes Educational score: 4.130144119262695 Domain: biomedical Document type: Study Language: en The network properties of nodes and edges were presented using code concurrence and code coefficients (Table 2 ). The weighted in-degree (wd) indicates a node’s connectivity and importance within the network, while the PageRank (PR) value measures network centrality, indicating the significance of a specific node. Table 2 Network metrics of the homogenous and mixed groups Network metrics Homogenous group Mixed group Nodes ( N ) 5 5 Edges ( N ) 10 9 In degree ( M ± SE) 4.0 ± 0 3.6 ± .49 Weighted in-degree .24 ± .05 .12 ± .03 PageRank ( M ± SE) .14 ± .02 .14 ± .02 Diameter 1 2 Density 1 .90 Modularity 0 0 Communities ( N ) 1 1 Path length ( M ) 1 1.1 Section title: Network Analysis of Themes Educational score: 3.015320062637329 Domain: biomedical Document type: Study Language: en Consistent PR values were observed for the “themes” at both mixed group and homogenous group levels, indicating similar centrality and importance throughout the networks. Additionally, all networks showed a single prominent community with comparable density and similar diameter, and the average path length indicated similar interconnectedness within the networks. Section title: Network Analysis of Themes Educational score: 2.3920390605926514 Domain: other Document type: Study Language: en In the homogenous group, despite the low code amount, the node “confidence” (wd = 0.14, PR = 0.106) played a central role in connecting to other nodes in the five-theme network community. Two distant nodes, “positive atmosphere” (wd = 0.28, PR = 0.146) and “collaboration” (wd = 0.27, PR = 0.158), were linked to “confidence.” The nodes “interpersonal relationship” (wd = 0.25, PR = 0.142) and “feedback-seeking behaviors” (wd = 0.26, PR = 0.149) were also closely connected to confidence. Section title: Network Analysis of Themes Educational score: 2.3932766914367676 Domain: other Document type: Study Language: en In the mixed group, a single five-theme network community was identified, with the central node being “motivation” (wd = 0.17, PR = 0.142). The nodes “positive atmosphere” (wd = 0.08, PR = 0.145) and “confidence” (wd = 0.09, PR = 0.106) played more peripheral roles in the network compared to the nodes “language learning” (wd = 0.12, PR = 0.149) and “collaboration” (wd = 0.12, PR = 0.159). Section title: Discussion Educational score: 3.524273633956909 Domain: other Document type: Study Language: en For research question 1, our findings indicate that the presence of supportive and encouraging partners boosts students’ confidence, playing a significant role in contributing to a notable improvement in their performance . Students in mixed groups initially exhibited high self-confidence during the pre-test but showed a decrease in confidence after the course, reflected in a negative normalized gain score. This drop in confidence was likely due to their reliance on positive feedback from native partners and the collaborative strategy of comparing themselves to their partners. In contrast, the homogeneous group likely did not experience such a drop in confidence as they were not directly comparing themselves to students with high performance levels. It is worth noting that there was an initially high confidence level in the nonnative students in the mixed group, which we infer was influenced by the initial encounters and assistance from native partners. The native partners consistently outperformed the nonnative students throughout the learning process, leading to a basis for comparison or appreciation among the students . The stark contrast in performance could have led to feelings of inadequacy and self-doubt, ultimately undermining their self-confidence . Constantly being overshadowed by their native partners could have eroded the students’ belief in their own abilities, resulting in a decrease in confidence over time . Section title: Discussion Educational score: 4.081493377685547 Domain: biomedical Document type: Study Language: en The similar proficiency levels in medical Dutch within the homogenous group likely facilitated their use of collaborative strategies by enabling better mutual understanding and support. Our study identified six collaborative strategy domains. Both groups emphasized language use, progress monitoring, and feedback. However, the homogenous group focused more on communication skills, likely due to their shared linguistic proficiency and understanding of challenges, enhancing intra-group communication. Moreover, the mixed group focused more on personal growth as collaborative strategies, which included self-improvement, reflection, analytical thinking, and confidence building (available as Supplemental Digital Appendix 4 ). We posit that this can be attributed to the role modeling effect, as documented in previous studies [ 35 – 37 ]. In the mixed group, native peers serve as valuable learning models, inspiring students to reflect on their own skills and qualities to emulate the successful behaviors and characteristics exhibited by these role models . Inspired by their native partners, students in the mixed group aimed to reach the level of competence demonstrated by these role models. Consequently, the homogenous group faced more challenging drawbacks than the mixed group . Section title: Discussion Educational score: 3.4529075622558594 Domain: other Document type: Study Language: en To understand the theme construct, we used network analysis to model relationships in both the homogenous and mixed groups in line with previous research that thoroughly investigated these themes to validate their construct [ 38 , 40 – 44 ]. In the homogenous group, confidence was central and closely linked to other themes, while motivation was central in the mixed group . These findings align with Kolb’s theory, which emphasizes the importance of a motivational environment and building students’ learning confidence to enhance their learning experiences . The use of native or nonnative partners in the course, as guided by Kolb’s theory and thematic analysis outcomes, effectively accounts for the differences in network themes observed between the mixed and homogeneous groups. Section title: Implementation Educational score: 1.405603289604187 Domain: other Document type: Other Language: en Our findings align with previous findings that nonnative partners contribute to creating a collaborative and positive atmosphere, enhancing concrete experience in a supportive learning environment, and boosting confidence in learning . Students’ confidence was strengthened through a combination of positive feedback from their partners’ observations and self-reflection on their progress and development during language learning . Section title: Implementation Educational score: 1.7049423456192017 Domain: other Document type: Other Language: en Based on Kolb’s theory, we delved deeper into how these themes correlate with the students’ perceived learning experiences . Themes like interpersonal relationships and feedback-seeking behavior align with the reflective observation stage . During this stage, students engage in interactions, seek feedback, and learn from interpersonal dynamics, fostering valuable experiences for reflection and growth . The mixed group excelled in abstract conceptualization and active experimentation. Language learning and motivation were linked to abstract conceptualization, where students develop knowledge and strategies while experiencing increased motivation . Active experimentation, focusing on language practice and immersion, positively influences students’ motivation during language learning . Section title: Implementation Educational score: 1.51634681224823 Domain: other Document type: Other Language: en We recommend using nonnative partners in the course’s initial stage to foster familiarity, collaboration, and confidence in overcoming shared challenges. In practice, native partners should be introduced in the later stages of the course to facilitate learning with highly competent and motivated partners, leading to improved language skills, overcoming drawbacks, and advancing to higher levels of medical Dutch competence . In future research, we suggest considering both native and nonnative study partners to improve curriculum design, given the limited native partner resources. This could help boost communication and performance in specialized fields like education, law, technology, and business. Fig. 8 From prioritized theme to prioritized stages Section title: Limitations and Future Work Educational score: 4.035467624664307 Domain: biomedical Document type: Study Language: en Our study had limitations that may have influenced the interpretation of results and discussions. The small sample size, particularly in the mixed group (4 pairs), led to higher standard deviation in the normalized gain score for research question one, making it difficult to definitively establish a decrease in the gain score. Future studies could replicate our design with a larger sample size to strengthen and expand our conclusions. The gender distribution in both groups was imbalanced, with a higher number of female students ( n = 13) participating compared to male students ( n = 3). In the international track of medicine program, more women (80%) enlisted than men. In our study, there were more women than men in both groups, especially in the homogeneous group. It is unclear whether gender could play a role in the learning outcomes. We hope future research will explore similar contexts with a balanced gender composition. The students and native-speaking partners were all familiar with each other since they were enrolled in the same program with 50 students/year at the university and have studied simulated patient consultation in English for 2 years. For other designs, students could become familiar with each other in small groups before pairing them up. Additionally, the unique nature of each network in the network analysis, along with differing parameters used to describe network attributes across groups, made direct comparisons challenging. Lastly, there was a discernible tendency to emphasize the advantages of native partners, although our study primarily did not involve interviewing native partners. We recommend that future study also conduct interviews or surveys on the native partners’ perceptions for gaining further understanding of near-peer teaching and mentoring. Section title: Conclusion Educational score: 1.8069759607315063 Domain: other Document type: Study Language: en This study found significant differences in perceived learning experiences between mixed and homogeneous groups. The homogeneous group showed increased self-confidence, while the mixed group experienced a slight decrease due to comparisons with native peers but showed more motivation and experimentation. Accordingly, nonnative partners are recommended for the initial stage of the course to boost students’ self-confidence, while native partners can aid rapid language improvement and motivation in the second half. In future research, we recommend exploring the optimal use of native and nonnative study partners in curriculum design, considering their unique advantages and limitations. Section title: Supplementary Information Educational score: 1.0537306070327759 Domain: other Document type: Other Language: en Below is the link to the electronic supplementary material. Supplementary file1 (DOCX 18 KB) Supplementary file2 (DOCX 18 KB) Supplementary file3 (DOCX 621 KB) Supplementary file4 (DOCX 31 KB) | Other | biomedical | en | 0.999998 |
PMC11699050 | Section title: Introduction Educational score: 4.03400993347168 Domain: biomedical Document type: Review Language: en The right heart catheterization (RHC) remains an important diagnostic tool, providing data on hemodynamics, cardiac output, and cardiopulmonary pressures to help clinicians make decisions in a variety of disease processes. With the development of the balloon floatation catheter (Swan-Ganz catheter) by Drs. Swan and Ganz in 1970, it attained widespread use without significant critical review due to its ability to obtain hemodynamic measurements at the bedside . Several studies in the 1990's and early 2000's investigating the use of pulmonary artery catheters (PAC) suggested that it led to detrimental effects including increased length of stay, inconsistent interpretation of data, and increased mortality. Ultimately this resulted in a substantial decline in its use . Despite such a dramatic change in utilization, it continues to play a key role in the diagnosis and management of pulmonary hypertension (PH), cardiogenic shock (CS), valvular heart disease, and evaluation prior to organ transplant, particularly of the heart and lungs. In this review, we discuss the indications, contraindications, complications, and interpretation of waveforms and measurements of RHC. Section title: Epidemiology of utilization of RHC Educational score: 4.059350490570068 Domain: biomedical Document type: Study Language: en The RHC was revolutionary with the availability of a balloon tipped, flow-directed catheter, giving clinicians the ability to place one at bedside and leave it in place for continuous monitoring. It achieved widespread use without empirical studies looking into the benefits or risks, and by the mid-1980s, up to 40 % of critically ill patients underwent RHC . Concerns over this widespread utilization led to several studies which called the safety into question. Furthermore, several meta-analyses, observational studies, and randomized controlled trials have also shown no survival benefit from PAC use in critically ill patients. Ikuta et al. studied the national trends in PAC use and found a 67.8 % decline from 1999 to 2013. Specifically, there was a significant reduction in PAC placed for hospitalizations involving respiratory failure (92.3 % reduction) and acute myocardial infarction (74 % reduction). HF admissions on the other hand, demonstrated a 56 % reduction until 2009 .. Hernandez et al. demonstrated similar trends with a decrease in PAC use in HF from 2004 to 2007, followed by an increase in 2014. The authors also showed that use of PAC in CS has declined from 2004 to 2014. Section title: RHC in cardiogenic shock Educational score: 4.310187816619873 Domain: biomedical Document type: Review Language: en With the ability to provide data on right and left sided filling pressures, CO, vascular resistance, and other hemodynamic parameters, the RHC provides valuable insight for the diagnosis and management of CS. Invasive hemodynamic monitoring can guide the use of vasoactive pharmacologic therapies and help determine when mechanical circulatory support (MCS) is necessary. Proponents state that invasive monitoring can guide therapy and optimize hemodynamics, however, several early studies showed a lack of benefit with use of the PAC in critically ill patients . Several studies that investigated use of RHC or PAC in CS are summarized in Table 1 . Cooper et al. set out to develop a noninvasive criterion for the diagnosis of CS and validated it against the PAC standard. Their noninvasive criteria utilized hypotension, hypoperfusion state, predisposition to CS, and echocardiographic findings and reported a sensitivity of 96.9 %, specificity of 90.8 %, positive predictive value of 64.6 %, and negative predictive value of 99.4 %. The authors suggested that these criteria be used to noninvasively exclude CS, while PAC be reserved to confirm CS in patients who meet criteria . Table 1 Summary of studies investigating use of RHC in CS. Table 1 Study name and author Primary indication Outcomes Comments “SUPPORT”, Connors et al. Critically ill patients in the ICU: acute respiratory failure, multiorgan system failure, CHF Patients with RHC vs no RHC: - Increased 30-day mortality (OR 1.24) - Increased LOS (14.8 days vs 13.0 days) - Increased resource utilization “ESCAPE”, Binanay et al. Severe symptomatic heart failure despite recommended therapies Use of PAC: - No difference in mortality (OR 1.26, 95 % CI 0.78 to 2.03) - Increased in-hospital adverse events (47 vs 25, p = 0.04) - No deaths related to PAC use Excluded patients in cardiogenic shock requiring inotropes, vasopressors, or MCS “PAC-Man”, Harvey et al. ICU patients; acute respiratory failure, multiorgan dysfunction, decompensated heart failure Patients with PAC: - No difference in hospital mortality (68 % vs 66 %, p = 0.39) - Similar hospital and ICU LOS No deaths related to PAC; Insertion related complications = 10 % O'Neill et al. Acute myocardial infarction complicated by cardiogenic shock with Impella use Use of PAC: - Improved survival rate of 63 % versus 49 % in patients with PAC use versus patients without PAC use “CardShock”, Sionis et al. CS Use of PAC: - Mortality was 42 % compared to 34 % in non-PAC patients ( P = 0.6) Most common complication was VT during PAC insertion (5.6 %, 4/71) “CSWG”, Garan et al. CS Complete PAC hemodynamic data: - lowest in-hospital mortality compared to no PAC assessment (OR 1.57; 95 % CI 1.06 to 2.33) and to incomplete PAC data (OR 1.71; 95 % CI 1.29 to 2.25) - No significant difference between no PAC compared to incomplete PAC data Complete PAC was defined as having all the following: PA systolic and diastolic pressure, PAWP, pulmonary artery saturation and right atrial pressure Hernandez et al. CS and HF without CS PAC use in CS - Lower mortality (35.1 % vs 39.2 %) PAC use in HF without CS: - Increased mortality (9.9 % vs 3.3 %) National Inpatient Sample, Retrospective cohort study Section title: RHC in cardiogenic shock Educational score: 4.051819801330566 Domain: biomedical Document type: Study Language: en In addition, PAC in patients with CS can help tailor management by identifying their unique hemodynamic profile e.g., a patient with a low cardiac index and high systemic vascular resistance (SVR) may benefit from afterload reduction strategies with agents such as Sodium Nitroprusside as opposed to utilizing an inotrope only strategy. This was further exemplified by Ranka et al. who showed that in patient's admitted with acute CS, RHC use was associated with a significant reduction in mortality in index admission by 31 %, a reduction in 30-day readmission rate, and a six-fold increase in left ventricular assist device (LVAD)/orthotopic heart transplantation during rehospitalization. The authors hypothesized that RHC allowed for early and accurate classification of CS and increased MCS or advanced therapy in cases of severe CS, resulting in improved outcomes . Together these data suggest that RHC should be considered in CS that remains refractory to initial therapy or when advanced heart failure therapies are being considered. Section title: RHC in cardiogenic shock Educational score: 4.108018398284912 Domain: biomedical Document type: Review Language: en In recent years, SCAI (Society of Cardiovascular Angiography&Interventions) definition and stages of cardiogenic shock and have been increasingly adopted in both research and clinical practices . Through stage A (at risk) to stage E (extremis), this new definition highlights the dynamic nature of the CS as well as the importance of timely recognition and interventions to improve the outcome of patients with CS. Right heart catheterization is helpful in both evaluation and prognostication of CS as described above. When there is concern for full blown CS, invasive hemodynamic measuring with cardiac index <2.2 L/min/m2 and pulmonary artery wedge pressure (PAWP) >15 mmHg remains to be gold standard for diagnosis. In addition, Cardiac power output (CPO) and Pulmonary artery pulsatility index (PAPI) are also useful hemodynamic index to identify the severe LV dysfunction and RV failure, respectively . Section title: RHC in cardiogenic shock Educational score: 4.25804328918457 Domain: biomedical Document type: Review Language: en Right heart catheterization and invasive hemodynamic monitoring have been recommended for guidance of utilization of MCS when treating CS, as clinical assessment of PAWP and CVP are often inaccurate and unreliable . All cardiogenic shock has decreased cardiac output, but they may have different hemodynamic profiles. In the setting of predominantly elevated left side filling pressure, an unloading device such as percutaneous LVAD can help decrease PAWP and improve CVP by reducing RV afterload. However, when there is commitment right sided congestion that is not responding to the LV unloading, diuresis or CRRT might be indicated to further improve the cardiac output. When there is more predominant RV failure evidenced by marked elevated CVP and RV dysfunction, pRVAD might be indicated for RV unloading. In the face of severe and rapid cardiopulmonary collapse, VA-ECMO is often used to restore organ perfusion. However, its use among CS patients with severe LV dysfunction may further increase left side filling pressure and cause pulmonary edema. pLVAD such as Impella can be added to the VA-ECMO to further unload the LV and improve the hemodynamics . Invasive hemodynamic monitoring has been shown to be associated with improved outcome of CS patients who received MCS. In a large retrospective study of 1414 patients with CS, the use of complete PAC-derived hemodynamic data prior to MCS initiation is associated with improved survival from CS . Section title: RHC in pulmonary hypertension Educational score: 4.117690086364746 Domain: biomedical Document type: Review Language: en RHC remains the gold standard to diagnose, risk stratify and classify PH. The European Society of Cardiology (ESC) and European Respiratory Society (ESR) guidelines recommend use of RHC to investigate when echocardiography findings demonstrate high probability of PH to determine the etiology and confirm the diagnosis, and to support treatment decisions . Additionally, RHC is recommended in patients with intermediate probability of PH by echocardiography and unexplained signs or symptoms of PH, particularly if they have co-morbidities that increase their risk of PH. Echocardiogram has been shown to have good correlation but only moderate precision of estimating the Pulmonary artery systolic pressure (PASP) value calculated from TR velocity . The errors in measurement of peak TRV signal can lead to under or overestimate of PASP. In a large study of 1695 patients who had both echocardiogram and RHC, echocardiogram was found to have sensitivity of 87 % and specificity of 79 % for PASP cut off value of 36 mmHg . Due to this limitation, echocardiographic information can only grade the probability of PH being present rather than making the diagnosis . Section title: RHC in pulmonary hypertension Educational score: 4.5568976402282715 Domain: biomedical Document type: Review Language: en The World Health Organization (WHO) classification categorizes PH into 5 groups based on the specific pathophysiology and response to treatment: Group 1: pulmonary arterial hypertension [PAH], Group 2: PH due to left heart disease; Group 3: PH due to lung disease and/or hypoxia; Group 4: PH due to pulmonary artery obstructions; Group 5: PH with unclear and/or multi-factorial mechanisms . Table 2 provides an overview of the classifications. Prior to 2019, PH was defined as a mean pulmonary artery pressure (mPAP) ≥ 25 mmHg at rest which was arbitrarily defined. A retrospective analysis of all normative published RHC data by Kovacs et al. found that supine mPAP at rest in healthy individuals was 14.0 ± 3.3 mmHg and two standard deviations above the mean (20.6 mmHg), would represent the upper limit of normal . According to ESC 2022 Guidelines, PH is defined as a mPAP > 20 mmHg. The Task Force included a pulmonary vascular resistance (PVR) ≥ 2 Wood units (WU) and a PAWP ≤ 15 mmHg to define all forms of pre-capillary PH . The hemodynamic definitions can help with determining the diagnostic groups as outlined in Table 3 . Currently, there are no treatments approved for mPAP between 20-24 mmHg and PVR between 2-3 WU. Table 2 Overview of the groups of pulmonary hypertension . Table 2 Classification of Pulmonary Hypertension Group 1: Pulmonary Arterial Hypertension (PAH) 1.1 Idiopathic 1.2 Heritable PAH 1.3 Drug- and toxin-induced PAH 1.4 PAH associated with 1.4.1 connective tissue disease 1.4.2 HIV infection 1.4.3 portal hypertension 1.4.4 congenital heart disease 1.4.5 schistosomiasis 1.5 PAH long-term responders to CCB 1.6 PAH with overt features of venous/capillaries (PVOD/PCH) involvement 1.7 Persistent PH of the newborn syndrome Group 2: PH due to left heart disease 2.1 Heart failure with preserved LVEF 2.2 Heart failure with reduced LVEF 2.3 Valvular heart disease 2.4 Congenital/acquired cardiovascular conditions leading to post-capillary PH Group 3: PH due to lung diseases and/or hypoxia 2.1 Obstructive lung disease 2.2 Restrictive lung disease 2.3 Other lung disease with mixed restrictive/obstructive pattern Group 4: PH due to pulmonary artery obstructions 2.1 Chronic thromboembolic PH 2.2 Other pulmonary artery obstructions Group 5: PH with unclear and/or multifactorial mechanisms 2.1 Hematological disorders 2.2 Systemic and metabolic disorders 2.3 Others 2.4 Complex congenital heart disease Table 3 Hemodynamic findings to categorize PH . Table 3 Type of PH mPAP PAWP PVR Pre-capillary (groups 1, 3, 4 and 5) >20 mmHg ≤15 mmHg ≥2 WU Isolated post-capillary (groups 2 and 5) >20 mmHg >15 mmHg <2 WU Combined pre- and post-capillary (groups 2 and 5) >20 mmHg >15 mmHg ≥2 WU Key hemodynamic measurements obtained from RHC that categorize PH. PH = pulmonary hypertension, mPAP = mean pulmonary artery pressure, PAWP = pulmonary artery wedge pressure, PVR = pulmonary vascular resistance, WU = Wood units. Section title: RHC in pulmonary hypertension Educational score: 4.042003631591797 Domain: biomedical Document type: Other Language: en In patients with newly diagnosed PAH, vasoreactivity testing is recommended in those with idiopathic, heritable or drug/toxin induced PAH only to assess for possible treatment response with calcium channel blockers . Inhaled nitric oxide (10–20 ppm) or intravenous epoprostenol are the two preferred agents which can be utilized in this setting. Based on data by Sitbon et al. a positive vasodilator response was defined as a reduction in mPAP ≥10 mmHg to reach a mPAP ≤ 40 mmHg with an increased or unchanged CO . Only 10 % of idiopathic PAH patients will be vasoreactive. Section title: RHC in pulmonary hypertension Educational score: 3.931889295578003 Domain: biomedical Document type: Other Language: en RHC is an important part of mortality risk stratification in PAH . Elevated right atrial pressure and reduced cardiac index have repeatedly been demonstrated to predict increased mortality risk in PAH. Elevated right atrial pressure is included in the REVEAL 2.0 risk score , a highly validated risk score that can help guide therapy. In patients with PAH, repeat right heart catheterizations are often utilized to determine the response to therapy. Section title: RHC in pulmonary hypertension Educational score: 4.2991862297058105 Domain: biomedical Document type: Review Language: en Even with hemodynamic measurements, it can be challenging to distinguish pre- and post-capillary PH in the setting of HF with preserved ejection fraction (HFpEF) or optimal volume status. Evocotive manuevers, such as exercise and fluid challenge, can be very useful to distinguish HFpEF for PH as a cause of dyspnea. The ratio of change in PAWP per change in CO >2 mmHg/L/min can be used to identify HFpEF . The saline challenge protocol can help differentiate Group 1 PAH from Group 2 PH and involves intravenous administration of a 500 mL 0.09 % saline bolus over 5 to 10 min . Although normal subjects can have an increase in filling pressures with a saline bolus, those with HFpEF had a steeper rise in PAWP comparatively . Several studies have demonstrated that a PAWP >18 mmHg after saline challenge is suggestive of post-capillary PH [ , , , ]. D'Alto et al. utilized the saline challenge to correctly reclassify five out of 66 patients without PH and eight out of 124 with pre-capillary PH into post-capillary PH . Left ventricular end-diastolic pressure (LVEDP) and PAWP are often used interchangeably to estimate left-sided filling pressures. However, several studies have demonstrated discrepancies between these two measurements leading to misclassification of PH group. PAWP underestimates LVEDP in older age and overestimates LVEDP in atrial fibrillation, rheumatic valve disease, or those with a larger left atrial diameter. If RHC and PAWP were used to classify PH group in the above situations, it would misclassify nearly 30 % of patients . Therefore, ESC/ESR guidelines recommend use of LVEDP when PAWP is unreliable . Some authors have advocated for earlier use of RHC in the diagnostic schema of PH than some societal guidelines have recommended . Section title: RHC in unexplained dyspnea Educational score: 4.170072555541992 Domain: biomedical Document type: Other Language: en Invasive cardiopulmonary exercise testing (iCPET) can be a valuable tool in evaluating unexplained dyspnea, especially when non-invasive workup is inconclusive. iCPET allows for the measurement of physiological data that facilitates diagnosis of exercise-induced PAH, exertional HFpEF, or preload dependent limitations to CO . It is also performed to measure the contribution of cardiac and lung pathology to a patient's symptoms in multifactorial disease and to determine the severity of cardiac limitations in heart failure with reduced ejection fraction . When performing iCPET, RHC and sometimes radial artery catheterization (vrs pulse oximetry) are obtained to measure cardiac hemodynamics and peripheral tissue oxygen consumption. Caution needs to be used in patients with significant arterial insufficiency or Raynaud's phenomenon as radial artery catheterization can induce acute limb ischemia. An upright or semi-supine cycle ergometer, treadmill, or arm ergometer are utilized until the resistance is increased and the patient is exhausted. The pulmonary arterial pressure, right atrial pressure, and mean arterial pressure are measured continuously, while PAWP, arterial blood gases, and lactate are measured every minute. Baseline ventilation and pulmonary gas exchange measurements are obtained and repeated throughout exercise testing . Section title: RHC in unexplained dyspnea Educational score: 4.127279281616211 Domain: biomedical Document type: Study Language: en Herve et al. investigated the accuracy of mPAP alone compared to mPAP combined with peak exercise total PVR (TPVR) and supine dynamic exercise testing and found that the combination of maximal mPAP >30 mmHg and TPVR >3 WU corresponded to a similar sensitivity (0.93) but an improved specificity from 0.77 to 1.0 when distinguishing healthy subjects from ones with exercise-induced PH. The authors, however, were unable to accurately differentiate if PH was caused by left heart disease or pulmonary arterial disease . While exercise PH has been reintroduced in the 2022 PH guidelines, there remain no proven therapies. In patients with PAH and HFpEF, Santos et al. hypothesized that exercise upright RHC would provide additional information for the diagnosis of HFpEF and PAH in patients with unexplained exertional dyspnea. Patients had same day supine resting RHC followed by iCPET. 212 patients had normal supine resting RHC, however, 46 (22 %) of these patients had abnormal iCPET results. The use of iCPET reclassified diagnosis for 16 (43 %) of patients. 12 (40 %) patients with HFpEF had normal cardiac profile and 4 (31 %) of patients with PAH had no intrinsic pulmonary vascular disease found with iCPET . This study highlighted the hemodynamic changes in relationship to position during iCPET which may alter the interpretation of the result . Section title: RHC in unexplained dyspnea Educational score: 4.1228861808776855 Domain: biomedical Document type: Study Language: en Although diagnostic criteria for exercise-induced PAH have been attempted, they remain controversial as normal ranges for mPAP are highly variable and dependent on age . Kovacs et al. found that there were no significant association with age and resting mPAP, however, mPAP during exercise was independently linked to age with nearly half of the subjects ages ≥50 years exceeding an exercise mPAP >30 mmHg. The authors also found that nearly 20 % of patients younger than 50 years of age had mPAP >30 with maximal exertion, making it difficult to define normal ranges during exercise . Cardiopulmonary exercise testing has proved to be useful in differentiating cardiopulmonary causes of dyspnea from others. Elevated PAWP/CO slope during exercise (>2 mmHg/L/min) is common in patients with dyspnea on exertion with normal wedge pressure at rest and predicts exercise capacity and heart failure outcomes .Single measurements at rest might be insufficient and exercise measurements may refine the HFpEF diagnosis. Section title: RHC in unexplained dyspnea Educational score: 3.5408236980438232 Domain: biomedical Document type: Study Language: en Due to the complex procedures and requirement of muti-specialty collaboration. The iCPETs are usually performed at larger referral centers. In a retrospective study of iCPET center at Brigham and Women's hospital, 530 of 864 referrals were investigated with iCPET, over a span of 3 years . Exercise PAH, HFpEF, dysautonomia, oxidative myopathy accounted for 16.6 %, 17.7 %, 21.1 % and 24.5 % of the final diagnoses, respectively . Section title: RHC in constrictive pericarditis and restrictive cardiomyopathy Educational score: 4.137867450714111 Domain: biomedical Document type: Review Language: en Constrictive pericarditis is associated with equalization of diastolic pressures in all chambers, impaired ventricular filling, and signs or symptoms of right heart disease. As restrictive cardiomyopathy can present with similar findings, it is important to differentiate these entities to determine whether pericardial stripping may be indicated. The diagnosis can be challenging, and differentiation between the two requires a comprehensive evaluation with physical examination, computed tomography, magnetic resonance imaging, echocardiographic, and hemodynamic findings. In constrictive disease, rapid ventricular filling occurs early in the cycle followed by a rapid increase in pressure due to the noncompliant pericardium. This results in a rapid “y” descent on the atrial pressure waveform and a “square root” sign on ventricular pressure waveform, which may also be noted on pressure tracings of restrictive cardiomyopathy . Section title: RHC in constrictive pericarditis and restrictive cardiomyopathy Educational score: 4.281607151031494 Domain: biomedical Document type: Study Language: en The most reliable hemodynamic signs of constrictive pericarditis are those related to respiratory variation in RV versus LV filling. Constrictive physiology is demonstrated by significant ventricular discordance during the respiratory cycle, whereas concordance of ventricular pressures is the rule in restrictive cardiomyopathy . There have been several criteria to help differentiate constrictive and restrictive disease, but they have poor sensitivity and specificity. The systolic area index is a ratio of the RV area to LV area in inspiration versus expiration, and a value >1.1 is 97 % sensitive and 100 % specific for identification of constrictive pericarditis . Other findings that differentiate the two can be found in Table 4 . Table 4 Comparative Findings of Constrictive Pericarditis and Restrictive Cardiomyopathy . Table 4 Constrictive Pericarditis Restrictive Cardiomyopathy Traditional findings End-diastolic pressure equalization LVEDP-RVEDP ≤5 LVEDP-RVEDP ≥5 Dip and plateau morphology Prominent rapid diastolic filling waves on LV tracings (≥5 mmHg; square-root sign) LV rapid filling wave <5 mmHg Right Ventricular Systolic Pressure < 55 mmHg > 55 mmHg Right ventricular end-diastolic pressure (RVEDP) RVEDP ≥1/3 RV systolic pressure RVEDP <1/3 RV systolic pressure Kussmaul's sign Failure of RA pressure to drop upon inspiration. Normal respiratory variation in mean RAP Dynamic findings Dissociation of intrathoracic-intracardiac pressures A difference ≥ 5 mmHg between expiratory and inspiratory gradients between the PAWP and LV early diastolic pressures Concordant variation with respiration yielding to a difference between gradients of <5 mmHg Ventricular interdependence An inspiratory/expiratory systolic area index ≥1.1 An inspiratory/expiratory systolic area index<1.1 Section title: RHC in pre heart and lung transplant workup Educational score: 3.86609148979187 Domain: biomedical Document type: Other Language: en RHC is an essential part of the evaluation for heart transplant. The International Society for Heart and Lung Transplantation (ISHLT) Guidelines recommend that RHC should be performed in all adult candidates prior to listing for cardiac transplant (Class 1, level of evidence C). Once patients are listed, RHC should be repeated at 3-to-6-month intervals, most notably in the setting of reversible PH or worsening HF symptoms . Section title: RHC in pre heart and lung transplant workup Educational score: 4.413379669189453 Domain: biomedical Document type: Review Language: en The presence of elevated PVR or PH that is deemed irreversible with vasodilators remains a contraindication to isolated heart transplant, as the donor right ventricle may fail in the operating room or immediately postoperatively in the face of high PA pressures . Candidates with PVR > 5 WU and transpulmonary pressure gradient (TPG) > 15 mmHg have an increased 30-day mortality, and RHC remains crucial to recognizing these individuals . In patients with systolic PAP ≥ 50 mmHg and either PVR > 3 WU or TPG ≥ 15 mmHg, a vasodilator challenge with nitroprusside, IV prostanoids, or inhaled nitric oxide is indicated. Patients deemed to be reasonable candidates for transplantation are able to achieve a PVR of ≤3 WU while keeping systolic blood pressures above 85 mmHg . If the vasodilator challenge fails and the patients significantly decompensate, as evidenced by elevated PAWP and central venous pressure (CVP), they should be hospitalized for continuous hemodynamic monitoring and optimized with diuretics, inotropes, and vasoactive agents for 24 to 48 h. If medical therapy fails to reverse PH, consideration can be given for a trial of termporary MCS or intra-aortic balloon pump although having a clear endpoint for support is needed. Durable LVAD may be considered in patients otherwise felt to be candidates (including careful attention to RV function) and in some cases longterm LV unloaded may result in improved PVR [double check literature on this]. It is also reasonable to trial milrinone for 3 to 6 months and then reevaluate hemodynamics. Hemodynamics should be measured at 3 to 6 months after LVAD according to ISHLT guidelines (Class IIA, Level of Evidence: C). When both medical therapy and MCS fail, these patients are categorized as irreversible PH and isolated heart transplant remains contraindicated . Klotz et al. attempted to reduce PVR < 2.5 WU and TPG < 13 mmHg in patients being evaluated for heart transplant using prostaglandin E1 (PGE-1). The 1-year mortality after heart transplant was 22 % in the PH group treated with PGE-1, while it was 14 % in patients without any PH. There was no statistical difference in survival between these groups . One of the indications for combined heart-lung transplant includes secondary pulmonary hypertension (in many cases related to congenital heart disease) that does not respond to therapy, inotropes, and/or MCS, however combined heart-lung transplant is only performed in a limited number of centers and organ scarcity has prevented any considerable volumes of this procedure. The RHC also plays an important role prior to listing for lung transplantation. The Lung Allocation Score is utilized to waitlist patients based on mortality and posttransplant survival .. While the LAS takes some hemodynamic metrics of PH into consideration, PAH patients remain at a disadvantage in getting organs. Section title: RHC in other solid organ transplant evaluation Educational score: 4.062272071838379 Domain: biomedical Document type: Other Language: en Right heart catheterization has been also utilized in solid organ transplantation other than heart and lung for pretransplant evaluation. For orthotopic liver transplantation (OLT), guideline recommends mandatory screening for portopumonary hypertension (PoPH) with echocardiogram in all OLT candidates . For patients with elevated PASP (≥40 mmHg), RV dysfunction, LV dysfunction or significant valvular disease, RHC is indicated for evaluation degree and the type of pulmonary hypertension to further assess the candidacy of liver transplant . Brachial vein might be a preferred access site for RHC for patients with severe coagulopathy . For renal transplantation, the echocardiogram is indicated for patients who have been on dialysis for >2 years, has risk factors for pulmonary hypertension . For those who have an estimated pulmonary systolic pressure >45 mmHg should be referred for further evaluation with right heart catheterization . All patients being considered for pancreas should be evaluated with echocardiogram. For candidates with right ventricular systolic pressure (RVSP) >50 mmHg, a right heart catheterization is also recommended . Section title: RHC in detection and quantification of shunts Educational score: 4.227495193481445 Domain: biomedical Document type: Study Language: en An assessment of oxygen saturation of the superior vena cava (SVC) and the main pulmonary artery (PA) should be performed during RHC to detect presence of a shunt. A significant step-up in blood oxygen is defined as an increase in blood oxygen content or saturation that exceeds the normal variations of the right heart in the absence of a shunt [ , , ], and a step-up in oxygen saturation of >8 % should prompt further investigation with stepwise assessments of oxygen saturation, also known as detailed sampling . Upon confirming the presence of a significant step-up, measurements are obtained with fluoroscopic guidance and pressure measurement from the SVC (low and high), inferior vena cava (IVC) [low and high], right atrium (RA) [high, mid, and low], right ventricle (RV) [outflow tract, mid, apex], right ventricular outflow tract, main PA, left and right PA, and left ventricle (LV) as well as distal aorta in selected patients . The criteria for a significant step-up in oxygen saturation or oxygen content to signify a shunt are displayed in Table 5 [ , , ]. The magnitude of the shunt is then provided by the ratio of pulmonic flow to systemic flow (Qp/Qs), such that a Qp/Qs < 1 is managed conservatively, while a Qp/Qs > 1.5 warrants surgical or percutaneous repair . Table 5 Oxygen saturation associated with significant shunts [ , , ]. Table 5 Criteria for Step-Up Level of Shunt Atrial (SVC or IVC to RA) Ventricular (RA to RV) Great Vessel (RV to PA) Δ Mean O2 %Sat (distal and proximal chamber samples) ≥7 % ≥5 % ≥5 % Δ Highest O2 %Sat (distal and proximal chamber samples) ≥10 % ≥5 % ≥8 % Section title: RHC in valvular heart disease studies Educational score: 3.177748680114746 Domain: biomedical Document type: Other Language: en The evaluation of valvular heart disease using invasive hemodynamics has fallen out of favor largely due to improvements in non-invasive imaging. When echocardiography and other noninvasive imaging is inconclusive, RHC can be considered per the ESC guidelines . Below are the following instances where RHC may prove to be useful in valvular disease: Section title: Aortic stenosis Educational score: 3.2959256172180176 Domain: biomedical Document type: Other Language: en In aortic stenosis, coronary angiography in addition to RHC is often utilized to evaluate for existing coronary artery disease and PH as part of the pre-transcather aortic valve replacement evaluation . Section title: Mitral stenosis Educational score: 4.081914901733398 Domain: biomedical Document type: Other Language: en RHC is indicated in patients with mitral stenosis who have symptoms of PH or when non-invasive measurements of the mitral valve are inconsistent. Simultaneous measurement of the PAWP and LV pressure are used to evaluate the trans-mitral gradient . The PAWP will frequently overestimate the trans-mitral gradient by 30 % to 50 %, as it does not account for a delay of transmission of pressure through the pulmonary circulation . Section title: Tricuspid regurgitation Educational score: 4.073418617248535 Domain: biomedical Document type: Study Language: en Stocker et al. showed that evaluation by invasive hemodynamic monitoring plays an important role in identifying patients with severe tricuspid regurgitation who would benefit from transcatheter tricuspid valve repair (TTVR). Patients were stratified into 3 groups by hemodynamic measurements to examine post-operative outcomes and mortality after TTVR. Expectedly, patients without any PH (mPAP <30 mmHg) and post-capillary PH (mPAP >30 mmHg, TPG ≤17 mmHg) demonstrated better post-operative outcomes and 1-year survival rate compared to patients with pre-capillary PH (mPAP >30 mmHg, TPG >17 mmHg). PAP, TPG, PVR, RV stroke work were predictors of all-cause mortality after valve repair, while PAWP, RAP, CO, and pulmonary artery pulsatility index had no significant association. The authors suggest invasive hemodynamic assessments should be used to stratify patients to select for TTVR . Section title: RHC in the diagnosis of lymphangitic carcinomatosis Educational score: 4.039673805236816 Domain: biomedical Document type: Study Language: en The use of blood drawn from a PAC in the wedge position may be useful in evaluating for lymphangitic carcinomatosis in patients who are unable to undergo invasive procedures, such as a lung biopsy. Masson et al. collected blood drawn through a wedged PAC and examined the cytologic characteristics in eight patients with lymphangitic carcinomatosis and 40 control patients divided into two groups (23 without cancer but various pulmonary disorders and 17 with cancer but without pulmonary metastases). Seven out of eight patients with lymphangitic carcinomatosis were found to have malignant cells on pulmonary microvascular cytology. The authors suggested this as an alternative method when a RHC is being performed for hemodynamic assessment or lung biopsy is too risky . Section title: RHC contraindications Educational score: 2.6806328296661377 Domain: biomedical Document type: Other Language: en Absolute Contraindications: presence of right-ventricular assist device, tricuspid or pulmonic valve endocarditis, and skin insertion site infection [ , , ]. Section title: RHC contraindications Educational score: 2.526977777481079 Domain: biomedical Document type: Other Language: en Relative Contraindications: severe acidemia (pH <7.1), and bioprosthetic tricuspid or pulmonic valve [ , , ]. Section title: RHC contraindications Educational score: 3.4256393909454346 Domain: biomedical Document type: Other Language: en Mechanical tricuspid valve has been traditionally thought to be absolute contraindication for RHC due to the risk of catheter entrapment, prosthetic vale damage or thrombosis formation, but it has been increasingly reported it can be safely performed in selected cases with precautions . Section title: RHC contraindications Educational score: 2.8728771209716797 Domain: biomedical Document type: Other Language: en Presence of left bundle branch block: a transient right bundle branch block induced by the catheter can lead to complete heart block. Although rare, placement of a standby pacemaker catheter is recommended . Section title: RHC contraindications Educational score: 3.9103505611419678 Domain: biomedical Document type: Study Language: en Coagulopathy: There are limited recommendations in the setting of coagulopathy which can also be corrected with transfusion. In a study by Betz et al., the bleeding complications were compared between patients with an INR < 1.8 and INR ≥1.8 (range 1.8–4.0). The overall bleeding complications were extremely rare occurring in 0.6 % (2/312) of patients, both who developed a hematoma requiring prolonged manual compression and belonged in the INR < 1.8 group . Section title: RHC complications Educational score: 4.167015075683594 Domain: biomedical Document type: Study Language: en RHC is an invasive procedure, and as with any procedure there are complications associated with each step. In the ESCAPE trial, only a total of 9 (4.2 %) procedural complications occurred, and none were associated with in-hospital deaths. These included infection (4 patients), bleeding (2 patients), catheter knotting (2 patients), pulmonary infarction (1 patient), pulmonary hemorrhage (1 patient), and ventricular tachycardia (1 patient) . PAC-Man (Pulmonary Artery Catheters in Patient Management in Intensive Care) demonstrated a complication rate of 9.5 % (46 patients) which included hematoma (4 %), arterial puncture (3 %), and arrhythmias (3 %). Similar to the ESCAPE trial, these complications were not fatal . A combined 5-year retrospective and 6-month prospective analysis looked at the number of adverse events and complications associated with RHC. Out of a total of 7218 RHC performed, there were 76 serious adverse (1.1 %) events during the study period. Seventy-two of these serious adverse events were non-fatal and twenty-one (28 %) of these non-fatal events resulted in a hospital admission or prolonged stay. The most common complications were related to venous access followed by arrhythmias. There were only four (0.055 %) procedure-related deaths during the study period . With the widespread use of point of care ultrasound in nearly all critical care settings, the rate of complication associated with insertion has improved compared to when PAC-Man and the latter study were published-2005 and 2006 respectively. Section title: RHC complications Educational score: 4.084282875061035 Domain: biomedical Document type: Study Language: en Complications with venous access include hematoma at insertion site, arterial puncture, pseudoaneurysm formation, pneumothorax, thoracic duct injury, or thrombosis. The rate of thrombosis varies on the insertion site, with subclavian access having the lowest thrombotic risk at 1.9 % and length of time left indwelling. The rate of pneumothorax is lower with the use of the internal jugular veins for insertion compared to the subclavian veins and obviously, non-existent with a femoral vein insertion . The next set of complications are related to insertion of the PAC and include arrhythmias, catheter knotting, and PA rupture. Cardiac arrhythmias from PAC are mostly transient and include premature atrial or ventricular contractions, although sustained ventricular and superventricular arrhythmias may occur. Right bundle branch block can occur in up to 5 % of PAC insertions, therefore, patients with pre-existing left bundle branch block (LBBB) are at a risk of a complete heart block making LBBB a contraindication for RHC unless immediate pacing is available during the procedure [ 7 , , , ]. Section title: RHC complications Educational score: 4.36781120300293 Domain: biomedical Document type: Study Language: en The most feared complication of RHC is PA rupture, and although the incidence remains low at 0.03 % to 0.2 %, it has a mortality rate of 70 %. When a patient with a PAC develops new onset hemoptysis, rupture of the PA should be suspected. It can be complicated by hemothorax or endobronchial hemorrhage and require emergent surgical approach such as a thoracotomy . PA rupture occurs from over-inflation of the PAC balloon or migration of the catheter tip , and risk factors include severe pulmonary hypertension, age > 60, use of anticoagulation, cardiopulmonary bypass, and mitral valve disease . In a study by Kearney and Shabot, PA rupture was seen in ten patients out of 32,442 (0.03 %) who required hemodynamic monitoring with PAC. All ten patients had hemoptysis and seven died. The authors found that emergent thoracotomy was essential for survival in the presence of hemothorax . In order to minimize risk, a chest x-ray should always be obtained before and after adjustment of the PAC, and fluoroscopy may be preferrable for PAC insertion in certain situations. Weinberg et al. showed that insertion under video fluoroscopy allows for positioning of the catheter with less time, fewer attempts, and decreased rate of complications compared to PAC floated by real-time pressure waveform monitoring . It is also important to adopt safe techniques when using PAC. Avoid inflating the ballon in the distal pulmonary artery or against pressure. In case of suspected PA vascular injury due to right heart catheterization that resulted in significant bleeding, it is important to first secure the airway, often with endotracheal intubation. Acute hemostasis can be achieved by inserting a new Swan-ganz catheter into the same PA branch and inflating the ballon proximally to the bleeding site . The PA rupture can be treated endovascularly with stents, coil embolization or vascular plug or surgically with lobectomy . Indwelling PAC increased the risk of catheter site infection, bacteremia/sepsis, or right-sided endocarditis. Rowley et al. studied the frequency of right-sided endocardial lesions in catheterized patients. One or more right-sided endocardial lesions were found in 29 of the 55 catheterized patients, with four (7 %) of these lesions representing infective endocarditis while the remaining were uninfected. The authors observed infective and non-infective vegetations were in similar locations, including the pulmonic valve and right atrium, which would suggest it was a consequence of direct endocardial damage from the PAC. The length of time the catheter was in place was not significantly related to the frequency of the lesions occurring . Al-Hijji et al. studied the major adverse events from left heart catheterization (LHC) and LHC combined with RHC using the electronic medical record and ICD-9 codes. The combined risk of death, myocardial infarction, stroke, coronary dissection, pericardial effusion, or cardiac tamponade was 8.2 out of 10,000 procedures. Furthermore, adding a RHC to a LHC procedure did not increases risk of these complications . Pulmonary infarction was described by Foote et al. to be a result of thrombi formed around the catheter or catheter occlusion of the small pulmonary artery. Pulmonary infarction was found in 9 % of patients, and they recommended frequent chest x-ray to monitor for distal migration of the catheter tip . In another study, pulmonary infarction was found in 2 out of 112 RHC and both resulted from distal migration and pulmonary artery occlusion by the catheter . This necessitates monitoring with daily chest x-ray to lessen the risk. Overall, the rate of complications of PAC and RHC is low in the hands of an experienced provider. Section title: The American College of Cardiology/American Heart Association HF guidelines [ 82 ] Educational score: 1.3210078477859497 Domain: biomedical Document type: Other Language: en Class I: Section title: The American College of Cardiology/American Heart Association HF guidelines [ 82 ] Educational score: 3.6777379512786865 Domain: biomedical Document type: Other Language: en Invasive hemodynamic monitoring with a pulmonary artery catheter should be performed to guide therapy in patients who have respiratory distress or clinical evidence of impaired perfusion in whom the adequacy or excess of intracardiac filling pressures cannot be determined from clinical assessment. (Level of Evidence: C) Class IIa: Section title: The American College of Cardiology/American Heart Association HF guidelines [ 82 ] Educational score: 3.8688488006591797 Domain: biomedical Document type: Other Language: en Invasive hemodynamic monitoring can be useful for carefully selected patients with acute HF who have persistent symptoms despite empiric adjustment of standard therapies and: 1. whose volume status, perfusion, or systemic or pulmonary vascular resistance is uncertain; 2. whose systolic pressure remains low, or is associated with symptoms, despite initial therapy; 3. whose renal function is worsening with therapy; 4. who require parenteral vasoactive agents; or 5. who may need consideration for MCS or transplantation. (Level of Evidence: C) Class III: No Benefit Section title: The American College of Cardiology/American Heart Association HF guidelines [ 82 ] Educational score: 3.069457530975342 Domain: biomedical Document type: Other Language: en Routine use of invasive hemodynamic monitoring is not recommended in normotensive patients with acute decompensated HF and congestion with symptomatic response to diuretics and vasodilators. (Level of Evidence: B). Section title: European Society of Cardiology (ESC) and the European Respiratory Society (ERS) [ 16 ] Educational score: 3.961463212966919 Domain: biomedical Document type: Other Language: en Class I: 1. Patients with unexplained exertional dyspnea, syncope, and/or signs of right ventricular dysfunction should be screened with transthoracic echocardiography followed by confirmed diagnosis with RHC 2. RHC is required when treatment for PH is being considered. RHC is required to confirm diagnosis of pulmonary hypertension. It is required for diagnosis of PAH and Chronic thromboembolic pulmonary hypertension. 3. RHC is recommended in all cases of suspected PAH due to connective tissue disease 4. RHC is recommended for patients with congenital cardiac shunt to consider surgical correction 5. RHC is recommended in patients with PH due to left-sided heart disease (Group 2 PH) or chronic lung disease (Group 3 PH) if being considered for organ transplantation 6. High doses of CCBs are recommended in patients with idiopathic PAH, heritable PAH, and drug-induced PAH who respond to acute vasoreactivity testing. Reassessment after 3–4 months of therapy with RHC is recommended after treatment Class IIa: 1. RHC should be considered in pulmonary arterial hypertension (Group 1 PH) to assess the treatment effect of medications Section title: The International Society for Heart and Lung Transplantation Guidelines [ 16 ] Educational score: 3.9798617362976074 Domain: biomedical Document type: Other Language: en Class I, Level of Evidence C: 1. RHC should be performed on all candidates in preparation for listing for cardiac transplantation and annually until transplantation 2. RHC should be performed at 3- to 6-month intervals in listed patients, especially in the presence of reversible pulmonary hypertension or worsening of heart failure symptoms) 3. A vasodilator challenge should be administered when the pulmonary artery systolic pressure is ≥50 mmHg and either the transpulmonary gradient (TPG) is ≥15 or the pulmonary vascular resistance (PVR) is >3 Wood units while maintaining a systolic arterial blood pressure > 85 mmHg 4. When an acute vasodilator challenge is unsuccessful, hospitalization with continuous hemodynamic monitoring should be performed, as often the PVR will decline after 24 to 48 h of treatment consisting of diuretics, inotropes and vasoactive agents such as inhaled nitric oxide. Section title: RHC vascular accesses Educational score: 2.776052474975586 Domain: biomedical Document type: Other Language: en Venous access may be dependent on a variety of factors including operator experience, presence other cardiac devices, patient anatomy, and prior complications. Traditionally, femoral vein was used if a left heart catheterization was performed at the same time as a RHC. Section title: RHC vascular accesses Educational score: 3.7408294677734375 Domain: biomedical Document type: Other Language: en Internal jugular vein access is commonly used for patients in the critical care setting for continuous hemodynamic monitoring, and it is easier to manipulate into the PA compared to femoral vein access. Ultrasound is utilized for cannulation and a double Seldinger technique allows for lower risk of bleeding complications . Brachial vein access can also be utilized. This can easily be done by swapping out a 20G venous catheter and over the wire exchanging it for a 5–8 F sheath. Section title: Measurements and waveforms Educational score: 4.247031211853027 Domain: biomedical Document type: Study Language: en Consensus statements have recommended measurement of blood oxygen saturation from the distal PAC tip in the wedge position if PAWP is elevated or if its accuracy is questionable . A arterial oxygen saturation level would indicate true wedge position, while a lower than expected value would indicate incomplete occlusion of the PA. Viray et al. performed a prospective trial to determine the differences in PAWP values and PH classification utilizing oxygen saturation. Oxygen saturation was measured when PAWP measurements were >15 mmHg and occlusive saturation was defined as SaO2 > 90 % or within 5 % of systemic arterial saturation. If these criteria were not met, two additional attempts were made. The authors found that even with confirmation of PAWP by fluoroscopy and appropriate waveform appearance, an occlusive SaO2 was only obtained 50 % of the time. They found that 29 out of 45 (64.4 %) had significantly lower PAWP obtained with position confirmed by SaO2 compared to initial PAWP measurement, and 10 patients were reclassified - 6 changed from post-capillary to pre-capillary PH and 4 changed from post-capillary PH to combined pre- and post-capillary PH . Measurements and calculations can be referenced in Table 6 , Table 7 , and waveforms obtained from RHC are in Fig. 1 , Fig. 2 , Fig. 3 , Fig. 4 , Fig. 5 , Fig. 6 , Fig. 7 , Fig. 8 , Fig. 9 , Fig. 10 , Fig. 11 , Fig. 12 . Table 6 Direct hemodynamic measurements obtained from RHC. Table 6 Hemodynamic measurement Normal Range Comments Central Venous Pressure 2–6 mmHg Right atrial pressure 2–6 mmHg Right Ventricular Pressure (systolic and diastolic) Systolic: 15–25 mmHg Diastolic: 1–8 mmHg Pulmonary artery pressure (systolic/diastolic/mean) Systolic: 15–25 mmHg Diastolic: 4–12 mmHg Mean: 9–18 mmHg Pulmonary Artery Wedge Pressure 6–15 mmHg Recorded at end expiration, mean of three to five measurements Cardiac Output 4–6 L/min Determined using Thermodilution or Fick Mixed Venous Oxyhemoglobin Saturation (SvO 2 ) 60–75 % Table 7 Hemodynamic Measurements calculated from RHC measurements: Table 7 Hemodynamic measurement Calculation Normal values Systemic Vascular Resistance (SVR) mean systemic artery pressure – CVP CO 700–1600 dynes- sec /cm 5 Pulmonary Vascular Resistance (PVR) mPAP – PAWP CO 20–120 dynes-sec/cm 5 Cardiac Index (CI) CO BSA 2.5–4.0 L/min/M 2 Stroke Volume Index CI HR × 1000 ≥ 35 mL/m 2 Right Ventricular Stroke Work Index (RVSWI) mPAP – RAP × CI × 0.0136 HR 5–10 g/m 2 /beat Cardiac Power Output CPO = (mean arterial pressure − RAP) × cardiac output 1.0 W Transpulmonary Gradient (TPG) mPAP – PAWP < 12 mmHg Diastolic Pulmonary Gradient (DPG) Diastolic PAP – PAWP < 7 mmHg Pulmonary Artery Pulsatile Index systolic PAP – diastolic PAP RAP PAPi <1.85 RV failure after LVAD PAPi <1.0 RV failure in acute MI Oxygen Delivery CO × CaO 2 = CO × [(Hgb × SaO 2 × 1.34) + ] 1000 mL of O 2 /min Oxygen Uptake 1.3.4 × [CO × Hgb × (SaO 2 – SvO 2 )] CVP = central venous pressure, CO = cardiac output, mPAP = mean pulmonary artery pressure, PAWP = pulmonary artery wedge pressure, BSA = body surface area, CI = cardiac index, HR = heart rate, RAP = right atrial pressure, PAP = pulmonary artery pressure, CaO 2 = arterial O 2 content, Hgb = hemoglobin, SaO 2 = oxygen saturation, PaO 2 = partial pressure of arterial oxygen, SvO 2 = mixed venous oxygen saturation Fig. 1 Normal Waveform RA Pressure (Normal RA pressure waveform is described by the “a”, “c”, and “v” waves and “x” and “y” descents. The a wave represents atrial systolic. The c wave occurs with closure of the tricuspid valve. The x descent shows atrial relaxation with atrial diastole. The v wave is associated with rise in RA pressure due to RA filling during ventricular systole. Finally, the y descent occurs during RA emptying in early diastole when rapid ventricular filling occurs). Fig. 1 Fig. 2 Cannon A Waves (The cannon a wave are seen with with atrioventricular dissociation when the RA contracts against a closed tricuspid valve. These can be seen with ventricular tachycardia or complete heart block.). Fig. 2 Fig. 3 Loss of A Wave (The loss of a wave is seen with a loss of atrial contractions, primarily in the setting of atrial fibrillation.). Fig. 3 Fig. 4 Blunted Y Descent (The blunted y descent occurs in the setting of elevated RV pressures and in the following conditions: tamponade or tricuspid stenosis). Fig. 4 Fig. 5 Prominent X and Y Descent (A prominent x descent is found in constrictive pericarditis or cardiac tamponade. The y descent is prominent in found in constrictive pericarditis.). Fig. 5 Fig. 6 RV Pressure Waveform (The RV pressure waveform is shown above. Normal pressure ranges of the RV during systole are 15–25 mmHg while pressures during diastole range from 1 to 8 mmHg.). Fig. 6 Fig. 7 PA Pressure Waveform (The PA diastolic pressure will be representative of the PAWP. The dicrotic notch is when the pulmonic valve closes.). Fig. 7 Fig. 8 PAWP Waveform (This tracing represents the PAWP. Normal pressure ranges from 6 to 15 mmHg. The a wave represents left atrial contraction, and the v wave is associated with ventricular systole causing a rise in LA pressure. The x descent represents atrial relaxation, and passive filling of the LV is represented by the y descent.). Fig. 8 Fig. 9 Overwedge PAWP (Overwedging of the PAWP leads to falsely elevated pressures. The pressure waveform may become non-pulsatile as well). Fig. 9 Fig. 10 Underwedge PAWP (Under-wedging occurs in the setting of incomplete occlusion of the PA and leads to falsely elevated PAWP resulting in misdiagnosis of PH.). Fig. 10 Fig. 11 Waveform of Restrictive Cardiomyopathy (Restrictive cardiomyopathy shows concordance of ventricular pressures during respiratory cycle. The rapid y-descent can also be noted.). Fig. 11 Fig. 12 Waveform of Constrictive Disease (Ventricular discordance is found during the respiratory cycle in constrictive physiology. The square root sign can be found as a result of the rapid y-descent.). Fig. 12 Section title: Interpretation of results Educational score: 3.987348794937134 Domain: biomedical Document type: Study Language: en PVR ( Table 7 ) is a useful measurement to guide diagnostics and decision making for PAH, subtypes of PH, and heart transplantation. It provides important prognostic information about mortality in PH and heart transplantation patients. Pre-capillary PH is defined as mPAP >20 mmHg, PAWP ≤15 mmHg, and PVR ≥ 2 WU, while post-capillary PH consists of mPAP >20 mmHg, PAWP >15 mmHg, and PVR < 2 WU . Some data have recommended a PVR cut-off of 2.2 WU to differentiate subtypes, and values greater or equal to 2.2 have shown increased mortality . Section title: Interpretation of results Educational score: 4.026812553405762 Domain: biomedical Document type: Other Language: en Once diagnosis is established, pulmonary vasoreactivity testing is recommended for idiopathic PAH, heritable PAH, or drug-induced PAH. A positive response is defined as a reduction of mPAP ≥ 10 mmHg to reach an absolute value of mPAP ≤ 40 mmHg with an increased or unchanged CO. Responders are suitable for calcium channel blocker (CCB) therapy and long-term response is defined by New York Heart Association Functional Class I or II and sustained hemodynamic improvement after at least 1 year on CCB therapy alone . Section title: Interpretation of results Educational score: 4.028739929199219 Domain: biomedical Document type: Study Language: en Pulmonary effective arterial elastance (Ea) is regarded as a measure of total right ventricular afterload and represents both resistive and pulsatile components. In a study by Tampakakis et al., both Ea and pulmonary artery compliance were better predictors of mortality and right ventricular dysfunction than PVR or TPG in patients with PH due to left heart disease. The authors suggested these parameters could be utilized for therapies targeted towards RV load . Section title: Pitfalls in measurement and interpretation Educational score: 4.184965133666992 Domain: biomedical Document type: Other Language: en Although RHC provides data and insights that cannot be obtained from clinical exam, it is subject to variability and errors in measurement and interpretations. These errors can lead to misclassification of PH group resulting in inappropriate therapy in patients. The first step to avoid errors in measurement is to ensure the correct set-up of pressure lines and transducers. The pressure transducer should be zeroed at the mid-thoracic level, halfway between the anterior sternum and bed surface while the patient is lying supine. This represents the location of the left atrium, and deviations from can lead to alterations in measurement . PAWP should be measured at the mid a-wave of end-expiration with normal breathing (reference Tedford and/or others). Pressures are usually recorded as an average of three to five measurements . The PAWP will accurately reflect LA pressure when the catheter is located in West Zone III (define) where arterial pressure > venous pressure > alveolar pressure in the lung. This position allows for the best indicator of the LA pressure as it creates a continuous column of blood from the catheter directly to the LA. The alveolar pressure will be measured if the catheter ends up in Zone I or II, often signified by absence of a- and v-waves or PA diastolic pressure exceeding PAWP . Section title: Pitfalls in measurement and interpretation Educational score: 4.1016998291015625 Domain: biomedical Document type: Study Language: en In patients with chronic obstructive pulmonary disease, increases in intrathoracic pressure during end-expiration can lead to errors in mPAP and PAWP, and measurements should be averaged over the entire respiratory cycle . This may also be the case in obesity, although this should be interpreted with caution as obesity is strongly associated with HFpEF . While these observations were made using an esophageal pressure-transducing catheters as a surrogate of intrathoracic pressures, this technique is unlikey to be routinely employed . Positive end-expiratory pressure (PEEP) and mechanical ventilation affect RHC hemodynamic values. PEEP leads to increase in pleural and transpulmonary pressures causing reduced RV filling and increased RV afterload. This contributes to an elevated PAWP and overestimation of the LA pressure. Measurement for patients on positive pressure ventilation should be at end-inspiration. Section title: Pitfalls in measurement and interpretation Educational score: 4.04820442199707 Domain: biomedical Document type: Other Language: en Over-wedging or under-wedging can lead to erroneous PAWP measurements. Over-wedging occurs from excessive inflation of the balloon and makes values falsely low or high. When a catheter balloon is over-wedged, deflating the balloon usually fixes the issue. Over-wedging can lead to increased risk of PA rupture. Under-wedging occurs when the balloon is not completely occluding the PA and provides an artificially elevated measurement. This can be solved by deflating and then inflating the catheter until it wedges completely or sending it into a different PA branch . Section title: Cardiac output measurements Educational score: 4.200544834136963 Domain: biomedical Document type: Study Language: en Cardiac output (CO) can be measured by either Thermodilution (Td) or Fick methods. Td is obtained by injecting a fluid bolus into the right atrium, then measuring the temperature change of the fluid once it reaches the PA. This change in temperature is plotted against time, and the area under the curve is inversely related to CO . Inaccuracies with Td can occur in patients with severe tricuspid regurgitation, intracardiac shunts, arrythmias, and low CO states . The estimated oxygen uptake Fick (eFick) method estimates oxygen consumption (V̇O 2 ) using body surface area, age, gender, and heart rate, but it can be altered in the setting of HF, PH or abnormal body habitus . In a study comparing measured to estimated V̇O 2 , Narang et al. found that estimated V̇O 2 is inaccurate leading to a proportional error when deriving CO . Opotowsky et al. studied the correlation between eFick and Td in 15,000 patients undergoing RHC and found that CO estimates differed by >20 % in one-third of patients. Low CO/CI measured by Td was a stronger predictor of mortality compared to eFick. Therefore, Td remains the preferred method for CO assessment as it is a better predictor of all-cause mortality and prognosis in HF and PAH. Furthermore, even in the setting of tricuspid regurgitation, Td measurements were associated with mortality while eFick was not . Section title: Pulmonary artery catheterization in the CCU Educational score: 4.35612154006958 Domain: biomedical Document type: Study Language: en When the type of shock remains undetermined or there are signs to suggest multi-factorial shock, invasive hemodynamic data can be critical in timely diagnosis and monitoring therapy. Although routine use of PAC after ST segment elevation myocardial infarction (STEMI) is not recommended, it is recommended in patients with CS or hypotension after infarction to determine additional therapy and response. Overall 30-day mortality for CS associated with STEMI remains around 40–50 %, therefore recognition of those at risk is of utmost importance . Multi-factorial shock is particularly challenging to identify without hemodynamic data, and analysis of the patients in the SHOCK (Should we emergently revascularize Occluded Coronaries for cardiogenic shocK) revealed that 18 % of patients with CS showed signs of severe systemic inflammation manifesting as distributive shock. A reduced SVR was found to occur early during shock, prior to the diagnosis of sepsis, which suggested that vasodilation plays an important role in CS . In the SHOCK Trial Registry, cardiac power output (CPO) and cardiac power index (CPI) were independently associated with in-hospital mortality. CPO is calculated as the mean arterial pressure x CO/451, and a CPO ≤0.53 W had a sensitivity and specificity of 66 % for in-hospital mortality . Therefore, the use of RHC can provide additional data if patients do not present or respond to therapies in a classical pattern ( Table 8 , Table 9 , Table 10 ). Table 8 Calculations of Ea and PAC : Table 8 Hemodynamic Measurement Calculation Pulmonary effective arterial Elastance (Ea) End-Systolic PAP Stroke Volume Pulmonary Arterial Compliance (PAC) Stroke Volume Pulmonary Artery Pulse Pressure Table 9 Cardiogenic shock data interpretation [ 14 , , , ]. Table 9 Right Ventricular Dominant Left Ventricular Dominant Biventricular Dominant Variables CVP > 15 mmHg < 15 mmHg > 15 mmHg PAWP < 18 mmHg > 18 mmHg > 18 mmHg CVP/PAWP > 0.8 < 0.8 > 0.8 PAPI < 1.5 > 1.5 < 1.5 CI < 2.2 L·min −1 ·m −2 < 2.2 L·min −1 ·m −2 < 2.2 L·min −1 ·m −2 CPO < 0.6 < 0.6 < 0.6 Table 10 SCAI classification of cardiogenic shock (adapted) . Table 10 Description Typical Physical exam/bedside findings Typical Biochemical markers Typical Hemodynamics Stage A (at risk) A patient who is not currently experiencing signs or symptoms of CS, but is at risk for its development Normal JVP Warm and well perfused Normal lactate Normotensive B (beginning CS) A patient who has clinical evidence of hemodynamic instability (including relative hypotension or tachycardia) without hypoperfusion Elevated JVP Warm and well-perfused Normal lactate Hypotension (SBP < 90 mmHg, MAP<60 mmHg or > 30 mmHg drop from baseline) Tachycardia (HR > 100 bpm) C (classic CS) A patient who manifests with hypoperfusion and who requires one intervention(pharmacological or mechanical)beyond volume resuscitation Volume overload Lactate ≥ 2 mmol/L Cardiac index<2.2 L/min/m2 PAWP>15 mmHg D (deteriorating/doom) A patient who is similar to category C but is getting worse. Failure of initial support strategy to restore perfusion as evidenced by worsening hemodynamics or rising lactate Any of the C and worsening (or not improving) signs/ symptoms of hypoperfusion despite the initial therapy Any of the stage C and lactate rising and persistently ≥ 2 mmol/L Any of stage C and requiring escalating doses or increasing numbers of pressors or addition of a mechanical circulatory support device to maintain perfusion E (extremis) Actual or impending circulatory collapse Typically unconscious Lactate ≥ 8 mmol/L Profound hypotension despite maximal hemodynamic support Section title: CRediT authorship contribution statement Educational score: 0.929104745388031 Domain: other Document type: Other Language: en Bhavesh Katbamna: Writing – review & editing, Supervision. Lingling Wu: Writing – review & editing. Mario Rodriguez: Writing – review & editing. Phillip King: Writing – review & editing, Visualization. Joel Schilling: Writing – review & editing, Supervision. Jamal Mahar: Writing – review & editing. Ajith P. Nair: Writing – review & editing, Supervision. Hani Jneid: Writing – review & editing, Supervision. Elizabeth S. Klings: Writing – review & editing, Supervision. Gerald L. Weinhouse: Writing – review & editing, Supervision. Sula Mazimba: Writing – review & editing, Supervision. Marc A. Simon: Writing – review & editing, Supervision. Markus Strauss: Writing – review & editing, Supervision. Chayakrit Krittanawong: Writing – review & editing, Writing – original draft, Visualization, Validation, Supervision, Conceptualization. Section title: Ethical statement Educational score: 1.0104355812072754 Domain: other Document type: Other Language: en No ethical statement is neccessary. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Review | biomedical | en | 0.999997 |
PMC11699068 | Section title: Introduction Educational score: 3.7810676097869873 Domain: biomedical Document type: Study Language: en Listeria monocytogenes is an important food-borne pathogen causing life-threatening disease in immunocompromised populations . The main vehicle of infection is ready-to-eat food , which is often contaminated from the processing environment [ , , ]. Except for a decrease in the number of cases to 1887 in 2020 (the COVID-19 pandemic period), the general trend for listeriosis did not show any significant increase or decrease in the last decade. However, the mortality rate in EU increased to 18.1 % in 2022, higher than in 2021 and 2020 (13.7 % and 13.0 %, respectively) . Section title: Introduction Educational score: 4.125532627105713 Domain: biomedical Document type: Study Language: en L. monocytogenes is a Gram-positive, facultatively anaerobic, non-spore-forming, motile rod bacterium (in the range of 20–25 °C). Its cardinal growth parameters referring to the main intrinsic and extrinsic food environmental factors are well known ( T min = −1.5 °C, T opt = 37 °C, pH min = 4.39, pH opt = 7.0, pH max = 9.6, a w min = 0.92 μ opt = 2.0 h −1 ) and are successfully used in growth predictions . However, variability in growth should be expected and can be quantified considering experimental, biological, and strain differences . Section title: Introduction Educational score: 4.140726089477539 Domain: biomedical Document type: Study Language: en Recently, the term microbial ‘persistence’ was defined as the ability of a given organism to be established in niches (or harbourage sites) within the food and feed processing environment for a long term, despite the regular application of cleaning and disinfection . Long-term presence means months or years accompanied by growth or survival in specific places of the processing environment. Despite extensive research, the persistence mechanism of L. monocytogenes in the food processing environment remains a topic of interest . The main candidate phenotypic traits responsible for persistence include increased biofilm formation , formation of mixed biofilms , higher resistance to sanitisers and better growth in suboptimal conditions . While the contribution of biofilm formation and resistance to sanitisers has been extensively discussed for L. monocytogenes persistence, this study aims to add information on the contribution of growth rate to this phenomenon. Section title: Introduction Educational score: 4.051337242126465 Domain: biomedical Document type: Review Language: en Primary mathematical modelling enables the analysis of the behaviour of microorganisms involving spore germination, growth, inhibition, inactivation, or survival over time. It provides kinetic models with parameters that are, however, sensitive to changes in food environmental factors . The mathematical relationships between the primary model parameters and the independent variables, such as intrinsic and extrinsic factors, such as a w , pH , temperature or modified atmosphere, are usually the subject of secondary modelling. Combining primary and secondary models, even more sophisticated tertiary models or expert systems can be created to predict the fate of microorganisms in specific foods with known environmental factors. This approach may help food microbiologists and manufacturers ensure the microbiological quality and safety of food throughout the food chain. For these reasons, mathematical modelling and predictive microbiology approach are integral parts of microbiological exposure assessment and, in combination with dose-response models, are also an inevitable part of risk assessment . Section title: Introduction Educational score: 4.089378356933594 Domain: biomedical Document type: Study Language: en The present study focused on growth quantification and modelling using classical primary and secondary modelling to characterise the growth of a persistent and a sporadic L. monocytogenes strain. The main goal was to compare their growth responses in two media, Tryptic Soy Broth (TSB) and semi-synthetic cheese medium (SCM), and to assess the variability as well as the statistical significance of potential differences in their behaviour. Section title: Bacterial strains Educational score: 3.1843221187591553 Domain: biomedical Document type: Study Language: en L. monocytogenes LM9611-19 (LM-P) and L. monocytogenes LM120/5 (LM-S) were used as representatives of persistent and sporadic potentially non-persistent strains, respectively. Section title: Bacterial strains Educational score: 4.084392547607422 Domain: biomedical Document type: Study Language: en LM-P was isolated from ewes' milk stored in a cooling tank at a farm that produces raw milk cheese and identified by the State Veterinary and Food Institute, Dolný Kubín, Slovakia. It was classified as molecular serogroup IIa, clonal complex 14, sequence type 14 and was considered persistent based on <10 allelic differences in cgMLST (39 isolates during 18-month period) in our previous study . Based on testing according to Stepanović et al. and Di Ciccio et al. , the strain was classified as a moderate biofilm producer (data not shown). Upon testing substrate utilization with API Listeria (Biomérieux, Marcy l'Étoile, France), the strain gave typical results with a numerical profile 6510. Section title: Bacterial strains Educational score: 4.020636558532715 Domain: biomedical Document type: Study Language: en LM-S was isolated from the milking equipment filter in the same facility as LM-P and characterised in our laboratories. It was classified as molecular serogroup IIa, clonal complex 14, sequence type 91 and considered sporadic (single isolate for 18 months) in our previous study . Based on testing according to Refs. , the LM-S strain was classified as a weak biofilm producer (data not shown). Upon substrate utilization testing with API Listeria, the strain gave atypical results of positive fermentation of D-xylose and D-tagatose, resulting in a numerical profile 6711. Section title: Preparation of the basic bacterial suspension Educational score: 4.145714282989502 Domain: biomedical Document type: Study Language: en For growth experiments, freeze-dried L. monocytogenes strains were revitalised by incubation in TSB (Merck, Darmstadt, Germany) at 37 °C for 24 h with mild shaking (1.7 Hz). The culture was streaked on TSA (Merck) and incubated at 37 °C for 48 h. Plates with cultures were stored at 5 °C with re-inoculation every 14 days for a maximum of 5 times. Cultures preserved in this way were used to prepare the basic suspension by picking a well-isolated colony into 10 ml of TSB, mixed with vortex, and incubated at 37 °C with mild shaking (1.7 Hz). After 18 h, microbial counts were determined by spreading 200 μl of decimal dilutions in peptone saline (containing 8.5 g NaCl (Mikrochem, Pezinok, Slovakia) and 1 g peptone (Lab M, Heywood, United Kingdom) per 1000 ml) on the surface of TSA plates in duplicate. Counts were calculated and expressed according to ISO 4833–2 . The numbers determined for the basic suspension were used to adjust the inoculum so that, after adding 1 ml–300 ml of growth medium, the concentration at the beginning of each experiment was within the range of 10 2 –10 3 CFU/ml. Section title: Semi-synthetic cheese medium Educational score: 4.142032146453857 Domain: biomedical Document type: Study Language: en The semi-synthetic cheese medium (SCM) was prepared according to Kagkli et al. and Schrama et al. to imitate the nutritive potential of cheese. The following components were dissolved in 275 ml deionised water: 0.06 g CaCl 2 ·6H 2 O (Sigma-Aldrich, St. Louis, USA), 0.30 g yeast extract (HiMedia, Mumbai, India), 0.31 g MgSO 4 ·6H2O (Lachema, Brno, Czech Republic), 1.8 g L-methionine (Merck, Darmstadt, Germany), 2.04 g of KH 2 PO 4 (Centralchem, Bratislava, Slovakia), 3 g NaCl (Centralchem), 4.5 g casein (bioreagent for cell culture grade, Sigma-Aldrich) and 11.4 ml sodium DL-lactate (Sigma- Aldrich). The lactose stock solution was prepared by steam sterilisation at a temperature of up to 100 °C for 20 min. After cooling, 25 ml of the solution was added aseptically to the cheese medium base which finally contained 8.4 g of lactose (Slavus, Bratislava, Slovak Republic) in 300 ml. Using a 10 % NaOH solution (Mikrochem) or lactic acid (Lachema), the pH value of the complete medium was adjusted to pH 7.2 before sterilisation to obtain pH 7.0 ± 0.1 after sterilisation. The a w value of the medium was 0.974 ± 0.003. Section title: Quantification of L. monocytogenes and cultivation experiments Educational score: 4.092334747314453 Domain: biomedical Document type: Study Language: en A volume of 1 ml of the appropriate dilution of the basic bacterial suspension was aseptically added to a flask with 300 ml of TSB or SCM and thoroughly mixed. Inoculated growth media were incubated at temperatures of 6 °C, 10 °C, 16 °C, 22 °C, 25 °C, 30 °C, 37 °C, 40 °C and 43 °C. For quantification, 1 ml of the culture from each flask was taken at predetermined time intervals over a period until the bacterial population reached a stationary phase or for up to 14 h. Subsequently, 200 μl of certain set dilutions were plated on the TSA surface in duplicate. The agar plates were incubated at 37 °C for 24–48 h. Section title: Quantification of L. monocytogenes and cultivation experiments Educational score: 3.5110435485839844 Domain: biomedical Document type: Study Language: en Duplicate growth curves were constructed within each experiment in TSB at each temperature, except for 6 °C, 30 °C and 43 °C, at which two independent experiments were carried out. In SCM, two independent experiments were carried out in duplicates at each temperature. Section title: Evaluation of variability Educational score: 4.229032516479492 Domain: biomedical Document type: Study Language: en A) Inspired by Aryani et al. , who defined the experimental, biological, and strain variabilities for growth and inactivation rates of 20 strains of L. monocytogenes in detail, indices such as MSE and RMSE were estimated in this study. Indices were calculated for the growth parameters of LM-P and LM-S strains at each temperature. According to the mentioned authors, experimental variability was defined as the difference between duplicate experiments conducted in parallel at the same time on the same experimental day. Biological variability was defined as the difference between independently reproduced experiments of the same strain performed on different experimental days from new pre-cultures and newly prepared media, and strain variability means the difference between strains of the same species. B) Alternatively, experimental RMSE values were also calculated from primary growth curve data (experiments with two replicates). Then, biological RMSE resulted from the combined data of 2 experiments, each with 2 replicates (4 replicates altogether), and analogously, the strain RMSE was calculated from all combined growth data for both strains in each medium used. These data sets involved data from 4 experiments (8 replicates; Table 1 and Table 2 for 6 °C and 30 °C, respectively). The mentioned temperatures were chosen because they generally represent low and optimal growth temperature ranges, and also because the highest number of replicates was available at these temperatures. This approach can provide an additional perspective to the evaluation of experimental, biological, and strain variabilities. Table 1 Growth data of L. monocytogenes strains in TSB and SCM at 6 °C. Table 1 Strain n rep / n exp Medium Model parameters Statistical indices n λ (h) rate log N 0 log N end RMSE RMSE ave Variability R 2 (log CFU/h) (log CFU/mL) LM-P 2/1 TSB 45.0 0.022 3.58 9.24 0.063 0.072 experimental 0.999 15 42.6 0.022 3.55 9.43 0.084 0.998 15 70.0 0.022 3.22 8.97 0.072 0.998 12 67.0 0.022 3.19 9.00 0.069 0.999 12 LM-S 78.7 0.020 3.48 9.71 0.109 0.080 0.997 12 59.4 0.022 3.31 9.49 0.095 0.998 13 87.7 0.022 3.14 8.98 0.042 0.999 12 89.6 0.021 3.05 9.15 0.075 0.999 13 LM-P 2/1 SCM 98.9 0.020 3.18 7.65 0.110 0.121 experimental 0.996 11 107.9 0.021 3.23 7.52 0.211 a 0.987 11 103.9 0.021 3.36 7.63 0.072 0.998 13 108.8 0.023 3.27 7.58 0.091 0.997 13 LM-S 116.3 0.025 2.53 7.49 0.361 a 0.264 0.970 11 116.0 0.021 2.52 7.63 0.333 a 0.971 11 127.5 0.024 2.94 7.30 0.264 a 0.979 16 95.9 0.020 2.99 7.55 0.100 0.997 17 LM-P 4/2 TSB 42.3 0.021 3.33 9.21 0.388 0.289 biological 0.964 54 LM-S 78.9 0.021 3.28 9.45 0.371 0.968 50 LM-P SCM 104.0 0.021 3.28 7.60 0.133 0.994 48 LM-S 105.4 0.020 2.89 7.55 0.266 0.978 55 LM-P + LM-S 8/4 TSB 51.9 0.020 3.25 9.35 0.487 0.394 strain 0.945 104 LM-P + LM-S 8/4 SCM 105.0 0.020 3.10 7.56 0.301 0.971 103 a Declination of the numbers observed during the lag phase. n r ep - number of replicates within the experiment, n exp - number of experiments. Table 2 Growth data of L. monocytogenes strains in TSB and SCM at 30 °C. Table 2 Strain n rep /n exp Medium Model parameters Statistical indices n λ (h) rate log N 0 log N end RMSE RMSE ave Variability R 2 (log CFU/mL/h) (log CFU/mL) LM-P 2/1 TSB 2.6 0.469 3.58 9.45 0.106 0.069 experimental 0.998 16 2.5 0.464 3.55 9.43 0.075 0.999 16 2.0 0.452 3.63 9.34 0.041 0.999 15 1.7 0.446 3.57 9.38 0.054 0.999 16 LM-S 3.3 0.492 3.07 9.56 0.113 0.084 0.998 15 3.2 0.493 3.06 9.52 0.107 0.998 15 2.5 0.464 3.16 9.38 0.048 0.999 16 2.5 0.475 3.17 9.45 0.068 0.999 16 LM-P 2/1 SCM 3.6 0.383 3.80 7.93 0.107 0.085 experimental 0.996 14 4.1 0.439 3.77 7.82 0.103 0.997 12 4.0 0.363 3.75 8.03 0.081 0.998 18 3.4 0.344 3.73 7.97 0.049 0.999 18 LM-S 4.4 0.315 3.27 8.01 0.130 0.085 0.995 18 3.5 0.308 3.21 8.00 0.089 0.998 18 3.2 0.351 2.68 7.94 0.057 0.999 21 2.8 0.331 2.68 8.10 0.066 0.999 21 LM-P 4/2 TSB 2.3 0.475 3.49 9.25 0.181 0.157 biological 0.994 63 LM-S 2.8 0.476 3.10 9.48 0.150 0.996 62 LM-P SCM 3.7 0.372 3.76 7.93 0.131 0.994 62 LM-S 3.5 0.326 2.96 8.00 0.167 0.992 78 LM-P + LM-S 8/4 TSB 2.3 0.475 3.49 9.25 0.181 0.312 strain 0.985 125 LM-P + LM-S 8/4 SCM 3.5 0.341 3.36 7.79 0.444 0.937 140 n r ep - number of replicates within the experiment, n exp = number of experiments. Section title: Primary and secondary modelling Educational score: 4.041848182678223 Domain: biomedical Document type: Study Language: en The density of the cultures of both L. monocytogenes strains was evaluated as a function of time in the two growth media according to Baranyi's D-model using the Excel tool DMFit v. 3.5 (Institute of Food Research, Norwich, United Kingdom). To evaluate the effect of temperature on specific growth rate and lag phase (secondary modelling), non-linear regression using Excel Solver (Microsoft, Redmont, USA) was applied. Section title: Primary and secondary modelling Educational score: 4.247014045715332 Domain: biomedical Document type: Study Language: en Baranyi's model is described by the following equations: (1) y ( t ) = y 0 + μ max ⋅ A ( t ) − 1 m ⋅ ln ( 1 + e m ⋅ μ max ⋅ A ( t ) − 1 e m ⋅ ( y max − y 0 ) ) (2) A ( t ) = t + ln ( e − μ max ⋅ t + e − h 0 − e − μ max ⋅ t − h 0 ) μ max where y (t) = ln N (t), y 0 = ln N 0 , y max = ln N max , m is the parameter of the curvature of the growth line when the growth of microorganisms slows down from the exponential phase to the stationary phase. A (t) is an integral form of the adjustment function α ( t ) whose value increases with increasing time, t is time and h 0 is a dimensionless factor that quantifies the initial physiological state of cells and is related to lag phase ( λ ) by the equation h 0 = μ · λ . Section title: Primary and secondary modelling Educational score: 4.200123310089111 Domain: biomedical Document type: Study Language: en Using log 10 N in the DMFit tool, the main outputs of primary modelling were the growth rate k max (log CFU/mL/h) and the duration of lag phase λ (h). Before secondary modelling, k max was converted to μ max ( h −1 ) according to the equation μ max = k max ⋅ ln ( 10 ) . To describe the effects of temperature on the growth of L. monocytogenes strains in TSB and SCM at a w values of 0.995 and 0.974, respectively, the square root Cardinal model (sqrtCM) of Rosso et al. was used in the following form: (3) μ max = μ o p t ⋅ C M ( T ) (4) 1 λ = 1 λ o p t ⋅ C M ( T ) where (5) C M ( T ) = ( T − T max ) ⋅ ( T − T min ) 2 ( T o p t − T min ) ⋅ [ ( T o p t − T min ) ⋅ ( T − T o p t ) − ( T o p t − T max ) ⋅ ( T o p t + T min − 2 T ) ] Section title: Primary and secondary modelling Educational score: 4.09768009185791 Domain: biomedical Document type: Study Language: en In this work, a square root transformation of the whole cardinal model was used for both growth parameters μ max and reciprocal λ . The secondary model includes five parameters with biological meaning, namely, μ opt , λ , T min (theoretical minimum temperature), T opt (optimum temperature) and T max (maximum temperature above which growth is not likely). Except for normalising residuals, the modification allowed the estimation of parameters μ opt and 1/ λ opt in the original non-squared form, which is more practical particularly for μ opt (Eqs. (3) , (4) )). Section title: Statistical analysis and model validation Educational score: 4.009811878204346 Domain: biomedical Document type: Study Language: en Specific growth rates of the two strains at 6–37 °C were used for internal cross-validation, in which a set of μ max calc values for LM-P was validated with LM-S μ max exp values and vice versa. Due to statistically significant differences in μ max values, the data at 40 °C and 43 °C were excluded from this validation. Section title: Statistical analysis and model validation Educational score: 4.040544033050537 Domain: biomedical Document type: Study Language: en External validation of secondary rate models for both strains in cheese medium was performed using growth rates acquired from the ComBase Predictor (CBP) at a w 0.974, pH 7. For CMs in TSB, the experimental μ max values estimated by Bajard et al. in Mueller-Hinton broth (MHB) were used for validation. Data are collected in Suppl. Table S1 . Section title: Statistical analysis and model validation Educational score: 4.142247200012207 Domain: biomedical Document type: Study Language: en To evaluate the accuracy of fitting, the coefficient of determination ( R 2 ) and the root mean square error ( RMSE ) were calculated: (6) R 2 = ∑ i = 1 n ( y i o b s − y i c a l ) 2 ( y i o b s − y ‾ i c a l ) 2 (7) R M S E = ( y i o b s − y i c a l ) 2 n − p where y i o b s , y i c a l and y ‾ i c a l are the observed (experimental), calculated (predicted) and averaged μ max or λ data, respectively; n is the number of observations; and p is the number of model parameters . Section title: Statistical analysis and model validation Educational score: 4.013548851013184 Domain: biomedical Document type: Study Language: en The CMs for growth rate were externally validated using independent data excerpted from the Combase database at aw of 0.974 and pH 7 as well as the data from Ref. . The following equations were used to calculate validation indices bias and accuracy factors , : (8) B f = 10 ∑ i = 1 n log μ m a x i o b s - log μ m a x i p r e d n (9) A f = 10 ∑ i = 1 n | log μ m a x i p r e d − log μ m a x i o b s | / n Section title: Statistical analysis and model validation Educational score: 3.9256670475006104 Domain: biomedical Document type: Study Language: en According to te Giffel and Zwietering , the bias factor ( B f ) provides information on the distribution of the observed values towards the identity line between the observed (experimental) and predicted (calculated) μ max values. In this case, a value of B f lower than 1 indicates a ‘fail-safe’ prediction and a value of B f greater than 1 means a ‘fail-dangerous’ model. The accuracy factor ( A f ) describes how close are the predicted μ max to μ obs values. Section title: Statistical analysis and model validation Educational score: 3.9290475845336914 Domain: biomedical Document type: Study Language: en The statistical differences between μ max values of the two L. monocytogenes strains at each temperature were statistically evaluated using the Analyse-it Method Validation package ver. 6.15 (Analyse-it Software, Leeds, United Kingdom). Data were treated using Student's t-test followed by Tukey's test with the least significant difference of 95 %. Section title: Growth of L. monocytogenes strains Educational score: 4.088385581970215 Domain: biomedical Document type: Study Language: en In this work, 63 independent cultivation experiments were carried out with duplicate trials for the two strains, persistent LM-P and sporadic – potentially non-persistent LM-S, in TSB and SCM. TSB represented a theoretically optimal culture medium ( a w of 0.995, pH 7.0), while the semi-synthetic cheese medium simulated conditions that more closely resembled the internal environment of cheese ( a w of 0.947 ± 0.003, pH 7.0). The nine cultivation temperatures used (6–43 °C) covered almost the entire range of L. monocytogenes growth. In total, more than 120 growth curves were provided with growth parameters and statistical indices. Experimental, biological and strain variability was evaluated according to Aryani et al. using specific growth rates and were also based on the RMSE values of the growth curves from individual experiments or combined data from 2 to 4 experiments (4–8 replicates) performed at different times. Section title: Evaluation of variability Educational score: 4.127151012420654 Domain: biomedical Document type: Study Language: en To quantify the internal experimental, biological and strain variability of μ max according to Aryani et al. , we used μ max data recalculated from growth rates of all individual curves carried out in SCM at each temperature. In this way, we could evaluate the MSE values and compare RMSE values for our persistent and sporadic strains with those of 20 strains by Aryani et al. . The variances of μ max for our strains were independent of temperature. The following RMSE exp , RMSE biol , and RMSE str of 0.016 h −1 , 0.022 h −1 , and 0.017 h −1 were calculated, respectively, for both strains LM-P and LM-S in this study. Aryani et al. observed almost identical variability and the same trend between the values as we did in the current study, as RMSE biol was the highest, followed by RMSE str and RMSE exp . However, in the second case the RMSE values of growth curves, which are log 10 N -based and express the goodness of fit for the primary growth model, can also provide an opportunity to evaluate experimental, biological and strain variability. The RMSE average values (RMSE ave ) may come not only from individual trial duplicates conducted at the same time (experimental variability) or from experiments with duplicates performed at different times (biological variability) but also, in our case, from data combined from experiments with LM-P and LM-S (strain variability). Section title: Evaluation of variability Educational score: 4.106332778930664 Domain: biomedical Document type: Study Language: en Together with other growth parameters, the RMSE values are presented in Table 1 , Table 2 for temperatures of 6 °C and 30 °C, respectively. The experimental RMSE values fluctuated between 0.063 and 0.130 log CFU/mL for both strains, temperatures, and media with almost the same mean RMSE exp of 0.082 and 0.081 for 6 °C and 30 °C, respectively. Similarly, the RMSE ave values representing biological variability (2 experiments performed at different times containing data from 4 individual replicates) were 0.289 and 0.157 log CFU/mL for 6 °C and 30 °C, respectively. Finally, the highest average RMSE values of 0.394 and 0.312 log CFU/mL described the strain variability in both media (TSB and SCM) at 6 °C and 30 °C, respectively. Section title: Evaluation of variability Educational score: 4.095235824584961 Domain: biomedical Document type: Study Language: en In addition, the growth curves fitted with the Baranyi D-model using experimental data for both strains (LM-P exp + LM-S exp ; 8 replicates) and representing strain variability in each medium are shown in Fig. 1 (TSB in blue; SCM in yellow). We suppose that similar values could be found in the suboptimal temperature range. However, it could not be properly demonstrated as only one experiment with two replicates was performed in TSB at other temperatures within the study. Fig. 1 Growth curves of L. monocytogenes in TSB (blue) and SCM (yellow) at 6 °C and 30 °C. Merged data for LM-P and LM-S strains (LM-P exp + S exp ) come from 4 experiments and 8 replicates in total. Dashed lines represent fitted values ± standard error (SE) of the fit and the solid red line in the right button figure represents the recalculated growth curve using equalized N 0 of 2.96 log CFU/mL. Fig. 1 Section title: Evaluation of variability Educational score: 4.113425254821777 Domain: biomedical Document type: Study Language: en The comparison of variability based either on specific growth rates or fitting errors of growth curves needs to use relative indices. To do so, the ratios between the average RMSE values and μ -values were calculated for replicates, experiments, and combined strain data. Similarly, for relative indices based on growth curves, the ratio of RMSE and growth increases (log N end - log N 0 ) averages was used. The experimental, biological and strain variabilities based on μ data were represented with relative errors of 5.2 %, 4.0 % and 8.3 %, respectively. On the other hand, the relative indices based on the log N data showed slightly lower values of 1.6 %, 2.9 % and 6.1 %, respectively. It seems that both methods of evaluation provided acceptable outputs and, in this case, also certain relations between them could be defined. Except for one case, the relative indices doubled from experimental to biological and from biological to strain variability. Section title: Effect of temperature on growth parameters of L. monocytogenes strains in TSB and SCM Educational score: 4.231412887573242 Domain: biomedical Document type: Study Language: en The cardinal temperature model with inflection (CM) is one of the most widely used secondary models that reliably describes the effect of temperature in the full range of growth on microbial growth parameters. The model is often preferred as it provides four parameters that have biological interpretation. In contrast, the extended square root model contains two regression coefficients and parameters T min and T max , which are only theoretical minimum and maximum temperatures for growth and may differ significantly from the actual cardinal temperatures . Graphic presentations of the dependences of sqrt μ max and sqrt 1/ λ on the temperature for LM-P and LM-S in TSB (a w 0.995) and SCM (a w 0.974) are shown in Fig. 2 , Fig. 3 , respectively. The dashed lines represent the calculated data using standard errors of model parameters, which are summarised in Table 3 . Fig. 2 Modelling the effect of temperature on sqrt μ max of LM-P and LM-S strains in Tryptone Soy Broth (TSB) and semi-synthetic cheese medium (SCM). Fig. 2 Fig. 3 Modelling the effect of temperature on sqrt 1/ λ of LM-P and LM-S strains in Tryptone Soy Broth (TSB) and semi-synthetic cheese medium (SCM). Fig. 3 Table 3 Parameters of the square root CM model and statistical indices of fit for LM-P and LM-S strains in TSB and SCM. Table 3 Parameters CM sqrt 1/λ LM (TSB) CM sqrt μ max LM (TSB) CM sqrt 1/λ LM (SCM) CM sqrt μ max LM (SCM) LM-P SE LM-S SE LM-P SE LM-S SE LM-P SE LM-S SE LM-P SE LM-S SE T min (°C) −1.151 0.012 1.076 0.008 0.197 0.001 0.821 0.003 0.675 0.003 1.252 0.007 0.086 0.001 −1.115 0.005 T opt (°C) 40.820 0.134 36.895 0.133 37.203 0.030 36.376 0.066 38.923 0.105 38.811 0.103 38.026 0.091 36.367 0.063 T max (°C) 43.223 0.045 43.180 0.015 44.303 0.021 43.580 0.018 43.356 0.017 44.233 0.097 49.518 0.466 43.890 0.029 1/ λ opt (h −1 ) 0.704 0.024 0.495 0.016 – - 0.392 0.009 0.387 0.010 – – μ opt (h −1 ) – – 1.282 0.009 1.259 0.020 – – 0.944 0.018 0.894 0.013 RMSE 0.040 0.038 0.011 0.030 0.018 0.021 0.026 0.022 R 2 0.971 0.970 0.999 0.991 0.989 0.987 0.991 0.992 Section title: Effect of temperature on growth parameters of L. monocytogenes strains in TSB and SCM Educational score: 4.1998443603515625 Domain: biomedical Document type: Study Language: en The solid lines representing the sqrtCM model with sqrt μ max for both strains in both media agreed with the observed μ max in the suboptimal temperature range. Differences were found in the region beyond T opt . The μ max exp values for LM-P and LM-S strains in TSB and SCM did not show significant differences in the suboptimal temperature range (6 °C–30 °C) and at 37 °C in both media. At the 5 % significance level, this was confirmed by ANOVA, Student's t-test, and Tukey's test at each temperature. However, in the region between optimal and maximum temperature, which contained two experimental temperatures (40 °C and 43 °C), the differences between μ max exp values from repeated trials were statistically confirmed for both strains and both media . Interestingly, the values of sqrt μ max were higher for LM-P than for LM-S at the three highest incubation temperatures, but they were statistically significant only at the last two, 40 °C and 43 °C. Furthermore, both cardinal parameters T opt and T max determined by the sqrtCM model for sqrt μ max were also higher for LM-P than for LM-S in both media ( Table 3 ). In terms of growth rate, Magalhães et al. found that persistent and non-persistent strains showed different responses to NaCl and acidic conditions (pH 5). Average rates were significantly higher (p < 0.05) for persistent than for non-persistent isolates when grown at 22 °C, 2.5 %, 4 %, 8 % NaCl, and at pH 5. In our case, the situation was different as significantly higher growth rates were observed for the persistent strain in both media only at temperatures higher than 37 °C (at 40 °C and 43 °C). Section title: Effect of temperature on growth parameters of L. monocytogenes strains in TSB and SCM Educational score: 3.8995180130004883 Domain: biomedical Document type: Study Language: en A similar trend could be observed in Fig. 3 , which is the output of the sqrtCM model application to the lag phase. In this case, higher values of sqrt 1/ λ, which means a shorter lag phase, could be seen more clearly in the region of temperatures beyond T opt . Likewise, the T opt values resulting from secondary modelling of sqrt 1/ λ against temperature were higher in the case of LM-P in both media ( Table 3 ). Section title: Effect of temperature on growth parameters of L. monocytogenes strains in TSB and SCM Educational score: 4.078598976135254 Domain: biomedical Document type: Study Language: en Magalhães et al. estimated similar lag times for persistent and non-persistent isolates when grown at 37 °C, 22 °C and 4 °C but significantly shorter (p < 0.05) for persistent strains grown at 2.5 %, 4 % and 8 % NaCl, and at pH 5. In our case, significantly shorter (p < 0.05) lag times were observed for persistent strain (in both media) only at temperatures 40 °C. and 43 °C. However, the estimated T max values from the lag phase modelling were within the range of 43.2–44.2 °C for both strains and the media. Section title: Effect of temperature on growth parameters of L. monocytogenes strains in TSB and SCM Educational score: 4.165312767028809 Domain: biomedical Document type: Study Language: en The sqrtCM model fitted well all the data obtained from our experiments, as documented not only by the standard error of the parameters but also by the values of other statistical parameters such as RMSE and coefficient of determination R 2 ( Table 3 ). Associated with the minimal errors of estimation, all cardinal parameters for L. monocytogenes strains in this study were consistent with those mentioned by Bajard et al. , te Giffel and Zwietering and Jia et al. . Regardless of whether calculated on μ max or λ basis, in TSB or SCM, for a persistent or non-persistent strain, the most discussed cardinal parameter T min , here with estimation errors from 0.0003 °C to 0.012 °C, ranged from −1.2 °C to 1.3 °C. For LM-P strain, the range of T min values determined with the CM model in the two media was −1.2 to 0.7 °C with an average of 0.0 ± 0.8 °C (mean ± SD; n = 4). As in Table 3 , strain LM-S showed a slightly higher average T min of 0.5 ± 1.1 °C. A similar estimated minimum growth temperature of 0.6 ± 0.2 °C was reported for L. monocytogenes in pasteurised milk by Jia et al. . Section title: Model validation Educational score: 4.085575103759766 Domain: biomedical Document type: Study Language: en Even with sound statistical indices of the sqrtCM and model parameters shown in Table 3 , the results should be validated using independent data. In this work, growth data for two strains with different genetic and physiological characteristics offered an option of internal cross-validation, within which the sqrtCM model for LM-P could be validated with μ max exp values of LM-S and vice versa. As statistically significant differences were found between the μ max model and experimental data at 40 °C and 43 °C for the two strains, these data were excluded from internal cross-validation. Fig. 4 shows the comparison of two sets of predicted and observed μ max values (recalculated from sqrtCM) in SCM at a w of 0.974 for the suboptimal temperature range (6 °C–37 °C). Fig. 4 Comparison of the observed and predicted values at internal cross-validation with LM-P and LM-S in SCM. Fig. 4 Section title: Model validation Educational score: 4.161013126373291 Domain: biomedical Document type: Study Language: en Table 4 provides accompanying linear regression data for the predicted and observed μ max values with low parameter errors and acceptable RMSE 0.027 and 0.029, respectively. Table 4 Comparison of predicted and observed μ max values as a part of internal cross-validation. Table 4 Comparison between Linear regression and statistical parameters Intercept SE Slope SE RMSE R 2 predicted LM-P and observed LM-S μ max values −0.0047 0.0093 1.0544 0.0181 0.0270 0.9927 predicted LM-S and observed LM-P μ max values 0.0121 0.0097 0.9322 0.0176 0.0287 0.9912 Section title: Model validation Educational score: 4.108343601226807 Domain: biomedical Document type: Study Language: en The values predicted using the CM model for the LM-P strain slightly overestimated the experimental data for the LM-S strain. On the other hand, the calculated data for LM-S underestimated the experimental data for LM-P. However, the B f values of 1.12 and 0.98 for the LM-P and LM-S CM models, respectively, were close to 1.0. Furthermore, Fig. 4 showed that, on average, the experimental values for LM-S were higher than for LM-P in the range of 6 °C–37 °C. However, the opposite situation could be seen in the temperature range between T opt and T max . Section title: Model validation Educational score: 4.115901947021484 Domain: biomedical Document type: Study Language: en Square root CMs for growth rate were externally validated using independent data from Combase at a w of 0.974, pH 7 and from Bajard et al. . For Combase data, the bias factors for the LM-P and LM-S models in SCM were 0.93 and 0.96, respectively, while the accuracy factors were 1.09 and 1.07, respectively. This means that the sqrtCM model for both L. monocytogenes strains provided a ‘fail-safe’ prediction to Combase data with 9 % and 7 % accuracy. On the other hand, the validation of LM-P and LM-S models based on data from this study in TSB with experimental growth rates by Bajard et al. performed in Mueller-Hinton broth revealed ‘fail-dangerous’ predictions with B f 1.06 and 1.07, respectively. Both accuracy factors were equal to 1.15. Section title: Conclusions Educational score: 4.117786884307861 Domain: biomedical Document type: Study Language: en In this work, the question of whether persistent or sporadically L. monocytogenes strains can grow better was dealt with by a quantitative study using two strains in two media in response to various temperatures. In the suboptimal temperature range, the growth parameters of persistent and sporadic, potentially non-persistent strains were almost indistinguishable, and it seems that growth predictions of persistent strains may be performed using the data of non-persistent strains (and vice versa), e.g., in exposure assessment. However, the models revealed differences in the behaviour of the strains at 40 °C and 43 °C. The results suggest that secondary modelling is suitable for testing a panel of L. monocytogenes strains regarding the possible correlation of their growth characteristics with persistence in food processing environments. The approach used in this study proved to be effective in revealing different growth responses in the range of higher temperatures than T opt . It can be extended also for mild inactivation temperature range as some similar differences in behaviour between persistent and non-persistent strains might also be expected. Section title: CRediT authorship contribution statement Educational score: 1.0006335973739624 Domain: other Document type: Other Language: en Ľubomír Valík: Writing – review & editing, Writing – original draft, Visualization, Validation, Supervision, Software, Methodology, Funding acquisition, Conceptualization. Jana Minarovičová: Supervision, Methodology, Investigation. Eva Kaclíková: Writing – review & editing, Writing – original draft, Supervision, Methodology. Adriana Véghová: Methodology, Investigation. Tomáš Kuchta: Writing – review & editing, Writing – original draft, Resources, Conceptualization. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Study | biomedical | en | 0.999997 |
PMC11699074 | Section title: Introduction Educational score: 4.0749335289001465 Domain: biomedical Document type: Study Language: en An interview is a required part of nearly all medical school admissions processes. With a few exceptions, prior to the COVID-19 pandemic, most interviews were conducted in person and consisted of either an unstructured one-on-one interview or a structured interview such as the multiple mini-interview (MMI). To protect both applicants and medical school staff during the COVID-19 pandemic, all medical school interviews went to a virtual format, starting either mid-cycle in 2019–2020 or at the beginning of the 2020–2021 admissions cycle. The transition required either the use of existing video conferencing technologies (e.g., Zoom, Microsoft Teams), the creation of an in-house system, or the purchase of a virtual interview system from a third-party vendor. Virtual interviews for medical school admissions were not unknown prior to the COVID-19 pandemic. A study published in 2018 placed the number of virtual interviews at US allopathic medical schools at 10% . Virtual interviews for graduate medical education (i.e., residency and fellowship) were already being used by many programs prior to the pandemic . In May of 2022, the Association of American Medical Colleges (AAMC) recommended the continuation of virtual residency interviews . Several studies performed by residency and fellowship programs reported satisfaction with the virtual interview format [ 6 – 8 ]; however, some surveys found that in-person fellowship interviews were preferred by a majority applicants since they thought they could better evaluate a program’s facilities and meet faculty . Section title: Introduction Educational score: 2.083724021911621 Domain: other Document type: Other Language: en Despite the associated costs and extra time required to learn, create, and/or purchase a system, several advantages seemed to emerge, for both the applicant and the medical school. Personnel performing interviews enjoyed greater flexibility, and there were possible cost savings for the institution . For the applicant, costs associated with travel, lodging, and time off from work decreased significantly or disappeared entirely. Lowering the financial barriers is believed to provide a more equitable medical school admissions process and greater access to medical school programs, including those that may have been out of reach for some applicants . Decreasing the environmental impact of travel have also been seen as a reason to conduct virtual interviews . For these reasons, the AAMC has recommended that medical schools use virtual interviews with an optional in-person visit after acceptance . Section title: Introduction Educational score: 1.5686732530593872 Domain: other Document type: Other Language: en Despite the potential advantages for the applicant, there were concerns about virtual interviews. One of the most concerning was exacerbating existing implicit and explicit biases that disproportionately affect applicants have been unrepresented in medicine (URiM) [ 17 – 19 ]. There were also concerns for new sources of potential bias including decreased access to adequate computer resources and Internet access, the difficulty in some facial recognition software recognizing darker skin, and the potential negative effect on interviewers observing applicants’ personal home or work environments seen through the video feed . Section title: Introduction Educational score: 4.116230010986328 Domain: biomedical Document type: Study Language: en Few studies in the pre-COVID-19 era directly compared virtual and in-person medical school interviews, and only one used virtual MMI (vMMI) as the interview format . The University of New Mexico School of Medicine described their experience using a video-based platform in the pre-COVID-19 era but used a semi-structured interview format . Several medical schools, both in and outside the USA, have published their experience of switching from in-person MMI (ipMMI) to vMMI, and none of them commented on the differences between the URiM applicants and the rest of the interview pool [ 11 , 22 – 27 ]. Cork looked at Zoom vMMI and ipMMI and found the delivery of the MMI had comparable scoring . Hammond and colleagues compared a synchronous vMMI using Zoom and their pre-COVID ipMMI for pharmacy school admissions and found that the vMMI was a reliable alternative to the ipMMI . These forementioned studies did not specifically investigate race or gender as potential differences in the vMMI and ipMMI performance. This lack of comparison between vMMI and ipMMI performance across demographic factors is surprising given well-established literature on interview and rater bias and several articles describing how bias may manifest differently in the virtual setting [ 17 , 18 , 29 – 31 ]. This study describes a completely automated, synchronous MMI system using the same rater user interface for both vMMI and ipMMI with special attention paid to differences between different populations of interviewees. Section title: Methods Educational score: 3.3758344650268555 Domain: biomedical Document type: Study Language: en The vMMI was developed using .NET (.NET Foundation, Richmond, WA) and integration with Microsoft Teams web version (Microsoft Corporation, Richmond, WA). An in-house developed student information system, MedOneStop, was used as an admissions interface for applicants, admissions staff, and raters. Both the vMMI and ipMMI had applicants rotate through eight stations, each with a different rater (interviewer) . The same bank of MMI scenarios were used in both the ipMMI and vMMI. Scenarios that required interaction between two applicants were not used in the vMMI. Actors, either members of the community or medical students, were used in the ipMMI, but during the vMMI, the rater assumed the actor’s role. The raters were recruited primarily from the faculty, staff, and medical students at the University of Cincinnati College of Medicine (UCCOM) and Cincinnati Children’s Hospital Medical Center. First-time raters were required to attend a 1-hour online training session in addition to a general admission’s training session. Fig. 1 Comparison of in-person and virtual multiple mini-interview day sequence Section title: Methods Educational score: 1.7703324556350708 Domain: other Document type: Other Language: en There were usually two vMMI sessions per interview day. To avoid common pitfalls such as blocked pop-ups, camera, and microphone issues, applicants and raters were required to complete a computer and video systems check within 24 hours of a vMMI. Raters were instructed to enter “Rater” as their name for anonymity. A photo of the student was provided on-screen for applicant reference and identity verification. The raters were blinded to the applicant’s American Medical College Application Service (AMCAS) and UCCOM secondary applications. Section title: Methods Educational score: 1.4268678426742554 Domain: other Document type: Other Language: en Each group (raters and applicants) met in separate initial Teams meetings with the admissions staff prior to the start of the vMMI to verify attendance and system operation. After the initial meeting and the official time began, applicants were shown their first station scenario for a set period (3 min). At this point, the applicant’s and rater’s browser would automatically open a Teams window for the interview to begin (6 min). At the end of the interview, the windows closed automatically, and the applicant was shown their next scenario (3 min). During this 3-min interval, the raters had the option to evaluate and assign a score to the applicant. After this period, the next station interview automatically began. The cycle continued until all applicants had rotated through eight stations. The process was automatic and could not be stopped for any one applicant. If at any point during a virtual interview an applicant or a rater experienced technical issues, they could click a button to message for help from IT support. Section title: Methods Educational score: 1.6115831136703491 Domain: other Document type: Other Language: en The ipMMI took place in the UCCOM’s Simulation Center, and typically two MMI sessions were done per interview day. After meeting with the admissions staff, applicants waited outside an individual simulation room door. They had 3 min to review the MMI scenario that was attached to the door. Guided by prompts from an overhead intercom, the applicant entered the room, and the interview began (6 min). At the end of 6 min, the applicant was prompted to leave the room and move to the next door where they had 3 min to read the next MMI scenario. The process was automatic and could not be stopped for any one applicant. Section title: Methods Educational score: 1.927321195602417 Domain: biomedical Document type: Other Language: en The same MedOneStop rater interface was used in the vMMI and the ipMMI. Both MMI modalities were cored using a Likert scale with 5 being the highest score and 1 being the lowest. The raters were trained to score towards the mean. The raters had the option to evaluate and score the applicant during the three-minute interval or within 24 hours from the start of the interview. The rater’s scores were adjusted based on their overall scoring over the course of the interview cycle. Section title: Methods Educational score: 3.821848154067993 Domain: biomedical Document type: Study Language: en Virtual adjusted annual MMI scores from medical school applicants in the 2021 and 2022 admissions cycles ( N = 627) were compared with ipMMI scores from 2017 to 2020 (Table 1 ). Additional comparisons were made between applicant subgroups including reported gender applicant-reported gender identity (male and female) and minority status (URiM and non-URiM). We used the AAMC definition of URiM as “any U.S. citizen or permanent resident who self-identified as one or more of the following race/ethnicity categories (alone or in combination with any other race/ethnicity category): American Indian or Alaska Native; Black or African American; Hispanic, Latino, or of Spanish Origin; or Native Hawaiian or Other Pacific Islander” . The applicants select their race/ethnicity when completing the American Medical College Application Service® (AMCAS®) application. Table 1 Number of interviewed applicants by MMI method, gender, and URiM status Year MMI Method Female Male Total URiM URiM Female URiM Male 2017 ipMMI 271 296 567 94 46 48 2018 ipMMI 301 325 626 123 52 71 2019 ipMMI 303 329 632 163 74 89 2020 ipMMI 322 296 618 153 86 67 Total ipMMI 1197 1246 2443 533 258 275 2021 vMMI 275 275 550 165 92 73 2022 vMMI 352 316 668 170 89 81 Total vMMI 627 591 1218 335 181 154 Total 1824 1837 3661 868 439 429 MMI multiple mini-interview, ipMMI , in-person MMI, vMMI virtual MMI, URiM underrepresented in medicine Section title: Methods Educational score: 3.4878017902374268 Domain: biomedical Document type: Study Language: en Comparisons were made between applicant subgroups including reported gender (male and female) and minority status (URiM and non-URiM). To analyze the data, we conducted a three-way analysis of variance (ANOVA) with gender, URiM status, and application year group (in-person vs. virtual) as independent variables and the adjusted MMI score as the dependent variable. This approach allowed us to examine main effects and interactions between these factors. While Likert scale data are ordinal, the large sample size and the tendency for scores to be distributed around the mean justify the use of parametric statistics in this case. Levene’s test was used to assess the homogeneity of variances across groups. The UCCOM institution review board approved this research , including waiver of consent and the minimal risk to participants. Section title: Results Educational score: 4.1456451416015625 Domain: biomedical Document type: Study Language: en The three-way ANOVA revealed several significant findings regarding the effects of gender, URiM status, and application year group on MMI scores (Tables 2 and 3 ). Examining main effects, we found a significant influence of gender ( F = 25.707, p < 0.001), with females ( M = 0.066, SD = 0.417) scoring higher on average than males ( M = − 0.066, SD = 0.428). However, neither URiM status ( F = 0.063, p = 0.802) nor application year group ( F = 0.139, p = 0.710) showed significant main effects, indicating no overall differences between URiM and non-URiM applicants or between in-person and virtual MMI scores. Table 2 Descriptive statistics for adjusted MMI scores by gender, URiM status, and application year group Gender URiM App Yr (group) Mean Std. seviation N F N In-person 0.065 0.419 939 F N Virtual 0.048 0.393 446 F Y In-person 0.078 0.424 258 F Y Virtual 0.100 0.448 181 M N In-person − 0.057 0.421 971 M N Virtual − 0.055 0.419 437 M Y In-person − 0.092 0.444 275 M Y Virtual − 0.102 0.467 154 Overall − 0.001 0.428 3675 F (Overall) 0.066 0.417 1824 M (Overall) − 0.066 0.428 1837 N (Overall) 0.001 0.419 2803 Y (Overall) − 0.003 0.452 868 In-person (Overall) 0.000 0.428 2450 Virtual (Overall) − 0.002 0.428 1225 Table 3 Three-way ANOVA results for adjusted MMI scores Source Type III sum of squares df Mean square F Sig Corrected model 17.905 11 1.628 9.111 .000 Intercept 0.787 1 0.787 4.406 .036 Gender 13.778 3 4.593 25.707 .000 URiM 0.011 1 0.011 0.063 .802 App Year group 0.025 1 0.025 0.139 .710 Gender * URiM 0.834 1 0.834 4.667 .031 Gender * App year group 0.031 2 0.016 0.087 .917 URiM * App year group 0.028 1 0.028 0.155 .694 Gender * URiM * App year group 0.102 1 0.102 0.570 .450 Error 654.421 3663 0.179 Total 672.327 3675 Corrected total 672.326 3674 R -squared = .027 (adjusted R -squared = .024) Section title: Results Educational score: 3.7509663105010986 Domain: biomedical Document type: Study Language: en We observed a significant interaction between gender and URiM status ( F = 4.667, p = 0.031). URiM females tended to score higher ( M = 0.087, SD = 0.434) compared with non-URiM females ( M = 0.060, SD = 0.411), while URiM males tended to score lower ( M = − 0.096, SD = 0.452) compared with non-URiM males ( M = − 0.056, SD = 0.420). Section title: Results Educational score: 2.526973247528076 Domain: biomedical Document type: Study Language: en We found no significant interactions between gender and application year group ( F = 0.087, p = 0.917) or between URiM status and application year group ( F = 0.155, p = 0.694). Additionally, the three-way interaction between gender, URiM status, and application year group was not significant ( F = 0.570, p = 0.450). Section title: Results Educational score: 3.78391432762146 Domain: biomedical Document type: Study Language: en It’s worth noting that Levene’s test indicated unequal variances across groups ( F = 1.990, p = 0.026). While this suggests some caution in interpreting the results, the large sample size and the robustness of ANOVA to moderate violations of homogeneity of variance lend credibility to our findings. Section title: Discussion Educational score: 2.2824864387512207 Domain: other Document type: Study Language: en Virtual interviews were being used extensively in job recruitment before the COVID-19 pandemic. A 2015 survey done by FutureStep, a recruitment process outsourcing and professional search company, found that 75% of companies used real time (synchronous) video interviews. Despite the ubiquitous utilization of virtual interviews since the start of the COVID-19 pandemic, there is very little literature examining the role of bias specifically in virtual interviews. The AAMC introduced the Standardized Video Interview (SVI) as an online, asynchronous video interview designed to holistically assess applicants’ proficiency in two of the Accreditation Council for Graduate Medical Education (ACGME) competencies of interpersonal/communication skills and professionalism in the emergency medicine field . After 4 years, the AAMC discontinued the SVI due to the lack of interest and the challenge of scaling the SVI to the multiple residencies . A review of the data showed that SVI scores slightly favored Black applicants compared with white applicants and found no difference between Latino and Asian applicants compared to white applicants . While female applicants did better than male applicants, there was no mention about how Black female applicants did as a separate category. Section title: Discussion Educational score: 2.822600841522217 Domain: biomedical Document type: Study Language: en Our analysis revealed a significant main effect of gender on MMI performance, with females consistently outperforming males across both in-person and virtual formats. This finding aligns with previous research and warrants further investigation into the underlying factors contributing to this gender difference in MMI performance. Section title: Discussion Educational score: 1.4173310995101929 Domain: other Document type: Study Language: en The significant interaction between gender and URiM status provides new insights into the complexities of demographic factors in MMI performance. Notably, URiM females performed particularly well in the virtual MMI format, outscoring their non-URiM counterparts. This finding challenges concerns that virtual interviews might disadvantage URiM applicants and suggests that the virtual format may actually benefit certain demographic groups. Section title: Discussion Educational score: 1.876851201057434 Domain: other Document type: Study Language: en Contrary to some concerns raised in the literature, we found no significant main effect or interactions involving the application year group (in-person vs. virtual). This suggests that the transition to virtual MMIs did not systematically advantage or disadvantage any particular group, supporting the validity of virtual MMIs as an alternative to in-person interviews. Section title: Discussion Educational score: 2.1482582092285156 Domain: other Document type: Study Language: en To our knowledge, this is the first study looking at within group and between group differences of a synchronous, virtual, and in-person MMI and how the two modalities affect applicant scoring between demographic groups such as race and gender. Female applicants performing better than their male counterparts in both MMI and non-MMI in-person interviews is well documented in the literature [ 38 – 40 ]. Other studies have reported that URiM status did not affect MMI performance . Section title: Discussion Educational score: 1.4575470685958862 Domain: other Document type: Study Language: en The results of the SVI and this study both showed that Black applicants did better than their white counterparts in these video interviews, although the SVI was asynchronous and our vMMI is synchronous. The underlying reason for this finding is uncertain. There is no literature delving into the reasons why Black females would have better performance in a virtual interview. It should be noted that in a large multiple national study of in-person MMI and traditional interviews, 4993 interviewees who underwent 7516 interviews, there was no association with URiM status and interview performance; however, these interviews were conducted in-person . Section title: Discussion Educational score: 2.4017586708068848 Domain: biomedical Document type: Study Language: en Several limitations should be considered when interpreting these results. First, while we used parametric statistics (ANOVA) with Likert scale data, this approach is justified by our large sample size and the tendency for scores to distribute around the mean. However, future studies might consider alternative statistical approaches specifically designed for ordinal data. Section title: Discussion Educational score: 3.3888351917266846 Domain: biomedical Document type: Study Language: en Second, Levene’s test indicated unequal variances across groups. While ANOVA is generally robust to moderate violations of homogeneity of variance, especially with large and balanced samples, this should be considered when interpreting the results. Section title: Discussion Educational score: 2.3884084224700928 Domain: biomedical Document type: Study Language: en Finally, this study was conducted at a single institution, which may limit the generalizability of our findings. Multi-institutional studies would be valuable to confirm these results across different settings and populations. Section title: Conclusions Educational score: 4.113461494445801 Domain: biomedical Document type: Study Language: en The transformation from in-person multiple mini-interviews (ipMMI) to virtual multiple mini-interviews (vMMI) in medical school admissions amid the COVID-19 pandemic offered an unanticipated opportunity to examine biases and differences within a complex evaluation framework. Our study, conducted at the University of Cincinnati College of Medicine, stands as the first to describe and compare both vMMI and ipMMI modalities, with an emphasis on their effect on different demographic groups. Our study demonstrates that the transition from in-person to virtual MMIs did not introduce significant biases or alter performance patterns across demographic groups. The consistent gender effect and the complex interaction between gender and URiM status highlight the need for continued research into factors influencing MMI performance. These findings support the use of virtual MMIs as a viable alternative to in-person interviews, potentially offering a more accessible and equitable admissions process. Future research should focus on understanding the underlying mechanisms of these demographic differences and exploring ways to ensure fair assessment across all applicant groups. | Study | biomedical | en | 0.999997 |
PMC11699083 | Section title: Introduction Educational score: 3.8069546222686768 Domain: biomedical Document type: Other Language: en A novel optical fiber with micro-structured architecture, PCF, shows a longitudinal periodic pattern of air holes. Due to its unique architecture, the PCF exactly manages its optical properties, such as photon incarceration, variation, and nonlinear behavior. Because of its unique laser-guiding qualities, with features of configurable architecture, the PCF provides advantages such as superior light instruction, customizable dispersion features, and the possibility of a range of diversified uses like detecting telecommunications, and nonlinear optical technologies . There are very many applications of PCF across various disciplines (M. ) (S.K. ). The communication sector benefits from PCF by allowing faster data transmission while reducing signal distortion and dispersion. For sensing applications, PCF can be very useful because of its excellent reactivity to changes in the external environment, like temperature, pressure, and chemical concentrations. PCF provides accurate light delivery and imaging capabilities in healthcare imaging and laser-induced surgery. PCF finds applications in quantum physics, specifically in photon manipulation for quantum information processing and nonlinear optics for the generation of ultrafast pulses (J. ). Section title: Introduction Educational score: 4.184330940246582 Domain: biomedical Document type: Study Language: en THz radiation, in PCF, deals with the guiding and handling of electromagnetic waves in the frequency range of 0.1–10 THz. THz transmission is highly restricted along with low loss due to micro-structured air pores in PCFs (H. ; [null]). Due to the given property, the potential of THz spectral analysis, scans, and communication-related fields is huge with PCFs (H. ) (F.M. ). PCFs can be designed to produce effective and compact THz generators and sensors, due to which the potential of these new approaches in noninvasive material testing, healthcare diagnosis, and safety inspection has become very high (A.Y. ) (L. ) (J. ). A gas analyzer uses the special qualities of PCF to measure the amount of gas present by examining how illumination interacts with its molecules inside the fiber. Zhang Zhi-guo et al. proposed, "Gas sensing characteristics of the index-directed PCF using an air core" (Z. ). Simon alongside other fellows demonstrated, "Ideal PCF narrows for super continuum emitters boosted by blue" . To precisely monitor temperature swings, a PCF temperature gauge makes use of the fundamental properties of the PCF or heat-dependent fluctuations in its RI. Guolu as well as his mate innovated, "Refractive index and temperature measurements simultaneously using liquid-filled PCF and LPFG" (G. ). A pair parallel cores under each PCF framework make up a dual-core PCF detector, which enables asymmetric assessment for improved perception. Shanyong et al. proposed, "Transformation of Spatial Modes using Hybrid Dual-Core Photonic Crystal Fiber" (S. ). Section title: Introduction Educational score: 4.511883735656738 Domain: biomedical Document type: Review Language: en A PCF velocity tracker uses the relation amongst radiation and the turbulent media inside the PCF to estimate the motion of liquids or things that are moving. Khurram among his fellows suggested, "Two-dimensional bending Velocity Detector with Excellent Sensitivity Using an Elliptic Two-Core PCF" (K. ). Once placed under illumination, an object's surface, usually made of Au or Ag, and may vary its RI. This can be measured using surface plasmon resonance (SPR), a type of monitoring approach. SPR are produced whenever polarized radiation strikes the metallic layer at an exact point and causes its free ions to vibrate. Jian-Ying et al. performed, "Refractive index detecting properties of a photonic crystal fiber SPR sensor coated with carbon nanotubes" (J.Y. ). Two distinct radiation waves are used by a dual-wavelength enabled PCF device to improve sensitivity. It may assess several variables either linearly or in tandem by using numerous wavelengths, which increases the instrument's flexibility along with applicability. Inaki plus his fellows invented, "A Modular Dual-Wavelength Locked Fiber Laser Source with Switch ability for In-PCF Parametric Frequency Modulation in CARS Microscopy" (I. ). A hollow-core PCF (HC-PCF) monitor makes use of a special construction in which the centre of a fiber is encircled by a regular pattern of air gaps. The radiation can go across the HC in this layout. Nikoleta alongside fellows found, "Rapid Molecule Spectroscopy Employing a Hollow-Core Photonic Crystal Fiber Light" (N. ). A PCF biosensor detects biomolecular contacts by taking advantage of the special qualities of PCF. They enable exceptional responsiveness, label-free recognition, including immediate tracking by analyzing shifts in optical conveyance or resonant throughout the fibre induced by adsorption interactions. As such, they are essential resources in bioengineering along with healthcare. Iddrisu et al. preferred, "PCF-based SPR refractive index biosensor assaying: from new setups to exceptional detection limits" (I. ). The exact regulate of how photon travels is made possible by a hexagonal structure that contains air spaces encircling the center of a hexagonal PCF device. The accuracy and versatility of the scanner to determine different chemical alongside physical variables are improved by this construction. Shuvo et al. innovated, "An optical sensor based on hexagonal photonic crystal fibers (H-PCF) with minimal confinement loss and high relative sensitivity for the terahertz (THz) regime" (S. ). Mohammad as well as his partner suggested, "High-sensitivity gold-coated PCF biosensor with surface plasmon resonance technology" (M.R. ). The RI is a key factor in PCF since it controls and directs photons. The radiation may be contained alongside steered inside the interior of a fibre thanks to the sequential configuration of air spaces that either produces a bandgap of photons or alters the effective RI. Xili Jing alongside his mates performed," A PCF coated in silver that serves as the basis for a broadband SPR dual-channel sensor for temperature and refractive index measurements" (Z. ). Petrochemicals are crucially processed goods that utilize oil from petroleum, including gasoline, petrol as well as diesel. In several areas of the earth, gasoline is a necessity for both home and commercial use since it is often utilized as aviation fuel along with warmth and illumination purposes in lanterns alongside burners. Petroleum, often known as petrol, is an essential component of the automotive sector since it is largely utilized as oil for the engines with combustion in automobiles. In addition to powering a variety of vehicles, such as automobiles, buses, and trucks, diesel is a necessary component of commercial along with farming equipment. Diesel-powered vehicles run on this fuel. A. H. M. Iftekharul with his fellows demonstrated, "Using terahertz spectrum analysis to reveal new information about oil derivatives: the hybrid refractive index rectangle core photonic crystal fiber viewpoint sensing" . Khalid et al. offered, "Terahertz spectrum petrochemical sensing: a hybrid structure photonic crystal fiber refractive index method" (K.S. ). Md. Asaduzzamzn among fellows proposed, "Fuel quality assurance using terahertz region operation management and hybrid hexagonal circular hollow core PCF sensing" (M.A. ). R. Kanmani et al. suggested, "The terahertz spectrum effectiveness of providing core components for slotted core Q in PCF" (R. ). The distinctive characteristics of the fiber composition are used by a PCF chemical analyzer to identify and evaluate chemical elements. Such gadget provide excellent responsiveness, effectiveness, along with immediate tracking skills by taking advantage of variations in the movement of light or resonant inside the fiber brought about by connections to particular molecules. They enable quick and precise chemical ingredient analysis in a variety of domains, including process manufacturing oversight, clinical tests, along with surveillance of the environment. Kawsar with his partner established, "Creation of an optical sensor utilizing terahertz spectroscopy for chemical detection" . Diponkar Kundu et al. innovated, "Analyzing the Terahertz photonic crystal fiber sensor's performance in chemical detection" (D. ). Section title: Introduction Educational score: 4.610691070556641 Domain: biomedical Document type: Review Language: en Methanol is sometimes referred to as wood alcohol or methyl alcohol. It smells slightly pleasant and is a colorless, uncertain, burning solvent. It is extremely harmful to living things and may trigger serious illnesses, like as cataracts, organ harm, or even death, if consumed, inhaled, or absorbed through skin . Ethanol, sometimes referred to as alcohol or ethyl alcohol. It is a dynamic, ignited, transparent solution having a distinct flavour and smell that burns . Ethanol is harmless for humans to consume in moderation, compared to methanol. Because methanol and ethanol have rather distinct impacts on people's health and are used for very distinct purposes, it is important to distinguish between the two because methanol is extremely harmful that may trigger major health problems . In recent years, various techniques have been explored for methanol detection, including surface plasmon resonance (SPR) sensors, fiber optic sensors, and electrochemical methods. While these approaches offer some advantages, they often suffer from limitations such as lower sensitivity, reduced accuracy, or limited operational range. Photonic Crystal Fiber (PCF) sensors have gained significant attention due to their high sensitivity, low material loss, and ability to operate in the THz range, making them a promising solution for methanol detection in industrial and commercial applications where precision and safety are crucial. The structural properties of PCF sensors, such as their unique core design and air-hole arrangement, significantly enhance performance in the THz domain for alcohol detection (Z. ). These features improve light confinement and reduce loss, allowing efficient propagation of THz waves through the fiber. The high porosity of the PCF structure increases interaction between the guided light and the analytes (methanol and ethanol), boosting sensitivity to refractive index changes. This structural optimization is critical for achieving high detection accuracy and low material loss in the THz range. THz PCF sensors offer several advantages over traditional alcohol detection methods. They provide higher sensitivity and selectivity by leveraging the unique absorption characteristics of alcohols in the THz range, enabling precise identification of methanol and ethanol. The photonic crystal structure enhances light-matter interaction, improving detection accuracy. Additionally, PCF sensors operate non-invasively and require minimal sample preparation, making them faster and more efficient than conventional chemical or chromatographic methods. Their compact design also allows for real-time monitoring in various industrial and safety applications. Section title: Introduction Educational score: 4.0889787673950195 Domain: biomedical Document type: Study Language: en To address the critical need for distinguishing between methanol and ethanol, we propose a Photonic Crystal Fiber (PCF) sensor designed to operate in the THz range. This sensor leverages the unique properties of PCF, such as enhanced light confinement and low-loss propagation, to achieve high sensitivity in detecting refractive index variations associated with different alcohols. With its tailored heptagonal core structure, the sensor is optimized for real-time alcohol detection, making it suitable for both industrial and commercial applications where precise chemical identification is essential. This design not only improves detection accuracy but also enhances safety monitoring, offering a robust solution for environments where methanol contamination or misidentification can pose significant health risks. Fig. 1 illustrates the block diagram of the setup used to test the sensor's performance in detecting alcohol. This figure provides a schematic of the PCF sensor experimental setup, essential for detecting methanol and ethanol in controlled conditions. The setup enables a systematic investigation into how the sensor performs under varying alcohol concentrations and frequencies. Fig. 1 Schematic of experimental setup for proposed PCF sensor. Fig. 1 Section title: Methodology Educational score: 4.27230167388916 Domain: biomedical Document type: Study Language: en The first process of developing the PCF sensor using COMSOL Multiphysics involves determining as well as characterizing the size along with components of the PCF layout. Recent advancements in photonic crystal technology and THz source development have significantly improved the efficiency of PCF sensors by enhancing light confinement and reducing losses. Innovations in THz generation and detection have also lowered costs, making the sensors more affordable for practical applications. These developments have broadened the scope of PCF sensors for various industries, including alcohol detection, with better performance and accessibility. This model tries to simulate the energy transmission procedure through chemical action comprising alcohol (Methanol, Ethanol) and the exterior operation of the PCF using COMSOL Multiphysics for alcohol identification through PCF. We construct this new device and examine it with COMSOL Multiphysics. This PCF has an unusual heptagonal core, a unique heptagonal clad surface, with 14 airways (R 1 & R 2 ) that originate within the cladding. The heptagonal core is designed considering polygonal function of COMSOL Multiphysics alongside desired angle of 51°. Whereas 14 airways are created in two cycles. R 2 be the radius of outer circle that we have use to create the outer layer airholes by using difference function. Similarly, the inner airways cycle consists of 7 similar airways that are created in similar manner but instead of circle we consider heptagon with R 1 radius for this portion and also use difference function here to achieve this shape. Zeonex is the base material used for the suggested system. Suggested THz PCF sensors can distinguish between different types of alcohols by detecting their unique refractive index and absorption properties in the THz range. This capability enhances practical applications, such as preventing methanol contamination in industrial settings and ensuring public safety by accurately identifying hazardous alcohols in real time. Zeonex is a material with a pre-calculated Refractive Index (RI) of 1.53. But its core (C) uses RI to detect Alcohol, where RI for methanol and ethanol are 1.329,1.361 respectively. A Perfectly Matched Layer, or PML for short, is a computing borders that simulates proper instrument behaviour by absorbing outbound pulses as well as preventing rebounds. Here, Fig. 2 (a) Displays the cross-sectional structure, showing the heptagonal core and air holes that facilitate alcohol detection. The cross-sectional view of the heptagonal core structure reveals how air holes are arranged around the core, which enhances light confinement. This layout is crucial for achieving high sensitivity in detecting refractive index differences between methanol and ethanol. Fig. 2 (b) Depicts the stages in designing the heptagonal core structure of the PCF sensor. This figure illustrates the construction process of the heptagonal core, showing the layered assembly of air holes that optimize sensitivity. Each step in the construction enhances the sensor's ability to differentiate between analytes based on their refractive indices. Fig. 2 a): Cross-sectional view of the proposed heptagonal core PCF sensor. Fig. 2 (b): Step-by-step construction of proposed heptagonal core. Fig. 2 (c): Mesh representation of the proposed PCF sensor. Fig. 2 (d): Power density distribution for (I) methanol (II) ethanol Fig. 2 (e): Power confinement analysis in core and cladding for (I) methanol (II) ethanol Fig. 2 (f): Workflow for material selection, sample preparation, and analysis. Fig. 2 Section title: Methodology Educational score: 4.20229959487915 Domain: biomedical Document type: Study Language: en The discretized description of detector topology used in calculations is known as a mesh representation. Such a mesh consists of minor elements like triangular and quadrilaterals, which when combined roughly, may represent the intricate framework inside the PCF. The use of triangular and quadrilateral elements in meshing is vital for accurate simulation of our heptagonal core PCF sensor. Triangular elements are applied to irregular regions, while quadrilateral elements cover more structured areas, ensuring an optimal balance between precision and computational efficiency. This hybrid meshing improves convergence and reduces numerical errors, enhancing the accuracy of key parameters like Relative Sensitivity (RS) and Effective Material Loss (EML). As a result, the mesh ensures reliable analysis and performance of the sensor for methanol and ethanol detection. The principles regarding the transmission of light can be solved by techniques like the FEM, working by breaking the detector down to such functional components. There are 74 apex factors, 1309 border factors, and 11228 items in total. The minimal grade for a substance is 0.5861. Upon which Fig. 2 (c) Shows the meshing layout used in the simulation, illustrating triangular and quadrilateral elements for accuracy. The meshing diagram used in simulations shows how triangular and quadrilateral elements cover the PCF structure. This meshing improves computational accuracy, particularly in simulating the interaction between light and analytes within the core. Section title: Methodology Educational score: 4.003473281860352 Domain: biomedical Document type: Study Language: en A PCF sensor's power distribution explains how the power of light is dispersed evenly throughout a fibre's topology. Because of its cladding with sequential patterns of air pores, radiation within a PCF is firmly constrained inside its core and improves guidance via adjusted TIR, or optoelectronic bands. Extreme reactivity to fluctuations in the outside world is created via an evanescent area that extends through the panelling and primarily operates in a basic pattern. The spacing is often analyzed through computer modeling and testing, so as to optimize layout as well as functioning. It is of prime importance to the effectiveness of the sensor. Upon which Fig. 2 (d) depicts Visual representation of the power density distribution across the sensor when detecting methanol (I) and ethanol (II). showing how the design effectively confines light, which is critical for enhancing sensitivity to each analyte. Section title: Methodology Educational score: 3.9381978511810303 Domain: biomedical Document type: Study Language: en The PCF sensor density distribution is explained by the changes of RI in the core and the surrounding. Energy is mostly confined by the higher RI of the core rather than the cladding. This configuration affects the guiding of illumination, modal area confinement, and the susceptibility to external perturbations of importance to the optimization of detector performance for a wide range of applications. It is often periodic due to the designs of air vents in the flow. Upon which Fig. 2 (e) Shows power confinement in the core and surrounding cladding for methanol (I) and ethanol (II), demonstrating the sensor's sensitivity. emphasizing the sensor's capability to guide light with minimal leakage, a feature essential for precise detection. Section title: Methodology Educational score: 4.116416931152344 Domain: biomedical Document type: Study Language: en The simulation results indicated differences in Effective Area (EA) and spot sizes (SP), with EA values of 3.92 × 10⁻⁸ m 2 for ethanol and 3.54 × 10⁻⁸ m 2 for methanol, and SP values of 2.28 × 10⁻⁴ μm for ethanol and 2.12 × 10⁻⁴ μm for methanol. While these numerical differences suggest distinct optical properties for each analyte, a formal significance analysis was not performed since the data is derived from deterministic simulations rather than experimental iterations. In future work, we plan to incorporate sensitivity and uncertainty analyses to evaluate the significance of these differences. This will help us better understand how small parameter variations could influence the sensor's performance and ensure reliable detection of methanol and ethanol in real-world applications. Section title: Methodology Educational score: 4.2063446044921875 Domain: biomedical Document type: Study Language: en The design process for a heptagonal core Photonic Crystal Fiber (PCF) sensor begins with defining the problem, specifically the need for detecting methanol and ethanol based on their refractive indices to ensure safety and monitoring in various industries. The sensor is then designed with a focus on the heptagonal core structure, shape, and arrangement of air holes. Appropriate materials for the core and cladding, such as Zeonex or silica, are selected based on their refractive indices to ensure compatibility with THz sensing. The next step involves setting up the sensor simulation in COMSOL Multiphysics, configuring parameters like pitch, air hole diameter, and the operational THz range. The refractive indices of methanol and ethanol are inputted into the simulation to analyze their effects on light propagation through the sensor. The sensor's performance is evaluated based on key metrics, including Relative Sensitivity, Effective Material Loss, Confinement Loss, and Numerical Aperture. Finally, the sensor design is optimized by tweaking the geometrical parameters to achieve maximum sensitivity and low loss for both methanol and ethanol detection. Fig. 2 (f) Outlines the procedural flow from material selection to sample analysis for the PCF sensor. Outlines the comprehensive process from material selection to sample analysis, ensuring that each phase is optimized for high-performance detection in commercial and industrial settings. Section title: Numerical analysis Educational score: 3.501636028289795 Domain: biomedical Document type: Other Language: en Finite Element Method (FEM) is a computational method applied in science and technology for the solution of awkward problems. Simulation of optical characteristics and light transmission in PCFs utilizes FEM. Special visual features of PCF include adjustable divergence and strong ambiguity due to the sequential placement of ventilation pores throughout their length. FEM enables the segmentation of longitudinal shapes into PCF pieces, where the characteristics can be analyzed with accuracy; this way, it becomes easy to research electrical field dispersion, together with the general effectiveness of the fiber. Section title: Numerical analysis Educational score: 3.4927570819854736 Domain: biomedical Document type: Other Language: en Relative Sensitivity (RS) is a property that gauges the capacity of PCFs to limit alongside direct light in response to variations in the RI of their surrounding environment. On PCFs, there is a repeating pattern of air vents that influences the characteristics of guiding. Photon containment and the fiber's acoustic characteristics are measured by RS, which also measures changes in these holes or the RI difference. High RS in PCFs is essential for purposes such as recognition and telecommunications since it assures proper light direction alongside the responsiveness of environmental changes, giving the fiber fitter the ability to identify and quantify the impacts in the surroundings. Section title: Numerical analysis Educational score: 2.6869771480560303 Domain: biomedical Document type: Other Language: en Implement those computational equations to determine RS . (1) r = n r n e f f × p % Section title: Numerical analysis Educational score: 1.3822319507598877 Domain: other Document type: Other Language: en Nevertheless, P occupies its rightful place in identifying a member of RI. (2) p = ∫ s a m p l e R e ( E x H y − E y H x ) d x d y ∫ t o t a l R e ( E x H y − E y H x ) d x d y Section title: Numerical analysis Educational score: 1.862552285194397 Domain: other Document type: Other Language: en Conversely, quantities in MF are delimited by H x , while quantities in EF are conveyed by E x along a surface. Section title: Numerical analysis Educational score: 4.069762229919434 Domain: biomedical Document type: Study Language: en Firstly, we measured the RS about both P and FR at the same time. The vertical axis to be considered for RS and horizontal axis considered for FR or P. As we made variation in FR or in P then corresponding change will occur in the RS. Here pink curve for ethanol and brown curve for methanol represent the RS. Fig. 3 (a) Shows the relationship between frequency and relative sensitivity, demonstrating that the sensor achieves peak sensitivity at 3.2 THz, which is key for reliable detection of methanol and ethanol. Where the max RS for methanol and ethanol is 95.72 % and 97.55 % at f = 3.2 THz. By contrast, Fig. 3 (b) Examines how pitch affects sensitivity, revealing that certain pitch values enhance the sensor's ability to detect subtle differences in refractive indices, optimizing performance for each analyte. Fig. 3 Demonstrate the influence of the Relative Sensitivity (a) Frequency [THz] (b) Pitch [μm]. Fig. 3 Section title: Numerical analysis Educational score: 3.114229917526245 Domain: other Document type: Other Language: en In PCF, Effective Material Loss (EML) describes light retardation resulting from the fiber element's natural acceptance, silica, for example. The EML in PCFs depends on light restriction in the core and its interaction with the surrounding micro-structured cladding. Light interaction intensity with the fiber material depends on several things, which include the wavelength used and the air-hole layout concept. EML is one of the most important factors when it comes to determining the total loss for PCFs. It also affects how suitable and efficient they are for various applications, from sensors to telecommunications. Section title: Numerical analysis Educational score: 3.0834286212921143 Domain: biomedical Document type: Study Language: en Implement those computational equations to determine EML . (3) α e f f = ( ε 0 μ 0 ) 1 2 ∫ A m a x n α m a t | E | 2 d A 2 ∫ A L L S z d A Whereas the electric field is represented by E and the zeonex loss coefficient is α m a t . Section title: Numerical analysis Educational score: 4.0006208419799805 Domain: biomedical Document type: Study Language: en We are now exploring the EML of our proposed PCF. The relationship between EML, pitch, and operational frequency is highlighted in Fig. 4 . The vertical axis to be considered for EML and horizontal axis considered for FR or P. As we made variation in FR or in P then corresponding change will occur in the EML. Here pink curve for ethanol and brown curve for methanol represent EML. Where at f = 3.2 THz the EML finds 0.0066 cm⁻ 1 and 0.0044 cm⁻ 1 for methanol and ethanol respectively. To be more specific , Fig. 4 (a) Analyzes Effective Material Loss (EML) across frequencies, demonstrating the sensor's efficiency in retaining light within the core for both methanol and ethanol, which directly influences detection accuracy, while Fig. 4 (b) Illustrates the influence of pitch on EML, showing that an optimal pitch configuration minimizes loss, thereby enhancing light confinement and the sensor's overall sensitivity. Fig. 4 Demonstrate the influence of the Effective Material Loss (a) Frequency [THz] (b) Pitch [μm]. Fig. 4 Section title: Numerical analysis Educational score: 3.9648373126983643 Domain: biomedical Document type: Study Language: en An indicator of a PCF's capability of keeping photons within its core is Numerical Aperture (NA). It measures the spectrum of orientations at which the fiber can support photons and is dependent on the RI difference between the cladding and core. The microstructure configuration of air holes surrounding the core of PCFs determines the NA, and these holes can be tailored for delivering certain light-guiding characteristics. An increased NA, for systems that require precise modal containment and efficient transmission of light, indicates a stronger ability to capture and steer photons. Section title: Numerical analysis Educational score: 2.358869791030884 Domain: biomedical Document type: Other Language: en Implement those computational equations to determine NA . (5) N A = 1 1 + π A e f f f 2 c 2 ≈ 1 1 + π A e f f λ 2 Section title: Numerical analysis Educational score: 1.3407005071640015 Domain: other Document type: Other Language: en Utility wavelengths are represented by λ, while the PCF's EA is displayed by A eff . Section title: Numerical analysis Educational score: 3.995673179626465 Domain: biomedical Document type: Study Language: en As seen in Fig. 5 , the NA of the suggested PCF is examined by varying the pitch and frequency. The vertical axis to be considered for NA and horizontal axis considered for FR or P. As we made variation in FR or in P then corresponding change will occur in the NA. Here pink curve for ethanol and brown curve for methanol represent NA. Where at f = 3.2 THz the NA finds 0.270 and 0.257 for methanol and ethanol respectively. Fig. 5 (a) Shows How Numerical Aperture (NA) varies with frequency, indicating that the sensor captures light most effectively at specific THz frequencies, which is important for maximizing detection reliability. In the meantime, Fig. 5 (b) Examines the effect of pitch on NA, highlighting that a suitable pitch value enhances the sensor's photon capture, improving its responsiveness to changes in refractive index. Fig. 5 Demonstrate the influence of the Numerical Aperture (a) Frequency [THz] (b) Pitch [μm]. Fig. 5 Section title: Numerical analysis Educational score: 3.903003692626953 Domain: biomedical Document type: Study Language: en The Effective Area (EA) of PCFs is a measure of the cross-sectional region over which light is efficiently directed and contained in the fiber core. The EA is a parameter that impacts some of the important characteristics, such as dispersion and nonlinearity. The higher light intensity inside the core due to a small EA would thus enhance nonlinear effects and hence be useful for applications like supercontinuum generation. At the same time, a larger EA is preferred when high-power transmission is required since it reduces nonlinearity. The EA is defined by the core size and the configuration of air holes in the cladding, which can be modified to tailor the optical characteristics of the fiber for specific applications. Section title: Numerical analysis Educational score: 2.2346549034118652 Domain: biomedical Document type: Other Language: fr Implement those computational equations to determine EA . (6) A e f f = [ ∫ I ( r ) r d r ] 2 [ ∫ I 2 ( r ) r d r ] 2 Section title: Numerical analysis Educational score: 1.908383846282959 Domain: other Document type: Other Language: en Consequently, the E.field is displayed over the identifying component when I(r) = |E| 2 . Section title: Numerical analysis Educational score: 4.096219539642334 Domain: biomedical Document type: Study Language: en The present experiment investigates the link between EA and changes in the PCF's operating frequency and pitch. The vertical axis to be considered for EA and horizontal axis considered for FR or P. As we made variation in FR or in P then corresponding change will occur in the EA. Here pink curve for ethanol and brown curve for methanol represent EA. Where at f = 3.2 THz the EA finds 3.54 × 10⁻⁸ m 2 and 3.92 × 10⁻⁸ m 2 for methanol and ethanol respectively. The dependence of EA on frequency is shown in Fig. 6 (a), Investigates the effective area as a function of frequency, illustrating that controlling the core area is essential for achieving optimal light confinement and detection sensitivity. In addition, Fig. 6 (b) Shows the effect of pitch variation on the effective area, revealing that pitch adjustments help optimize the core's ability to contain light and increase the sensor's sensitivity to analytes. Fig. 6 Demonstrate the influence of the Effective Area (a) Frequency [THz] (b) Pitch [μm]. Fig. 6 Section title: Numerical analysis Educational score: 3.7743279933929443 Domain: biomedical Document type: Study Language: en In PCF, the Spot Size (SP) is the effective diameter of the optical mode enclosed in the fiber core. It is an important factor that influences the efficiency of coupling, bending losses, and modal dispersion of the light transmission. The core size and the configuration of the air pores in the cover define the spot size. In asymmetric photonic programs, smaller spot sizes lead to higher intensity and better phase confinement. However, in applications that need significant power, larger spot sizes minimize discontinuity, thereby improving the excellence of the beam and, consequently, decreasing the intensity. Using the PCF layout can modify the spot size to meet certain requirements regarding performance. Section title: Numerical analysis Educational score: 2.8783514499664307 Domain: biomedical Document type: Other Language: en Implement those computational equations to determine Spot size . (7) W e f f = R × ( . 65 × 1.619 × V − 1.5 + 2.789 × V − 6 ) Section title: Numerical analysis Educational score: 1.869350790977478 Domain: biomedical Document type: Other Language: en Whenever the altered FR band V and heptagonal core diameter R are used together. Section title: Numerical analysis Educational score: 4.051594257354736 Domain: biomedical Document type: Study Language: en Illustrated As in Fig. 7 , this section explores the relationship between pitch, operating frequencies, FR, and spot size. The vertical axis to be considered for SP and horizontal axis considered for FR or P. As we made variation in FR or in P then corresponding change will occur in the SP. Here pink curve for ethanol and brown curve for methanol represent SP. Where at f = 3.2 THz the SP finds 2.12 × 10⁻⁴ μm and 2.28 × 10⁻⁴ μm for methanol and ethanol respectively. Fig. 7 (a) Illustrates the variation of spot size with frequency, demonstrating that smaller spot sizes improve light confinement within the core, critical for achieving high detection accuracy. Conversely, Fig. 7 (b) Examines the effect of pitch on spot size, showing that fine-tuning the pitch results in an ideal spot size that maintains the balance between confinement and light intensity. Fig. 7 Demonstrate the influence of the Spot size (a) Frequency [THz] (b) Pitch [μm]. Fig. 7 Section title: Numerical analysis Educational score: 2.9763996601104736 Domain: biomedical Document type: Other Language: en The term Dispersion (DP) of light in a PCF instrument indicates that the unique geometry of the fiber causes its velocity of a beam to change with its wavelengths. PCFs may exhibit abnormal or normal dispersion, depending on the specifications of their structure. Briefer wavelengths transmit more quickly under ordinary variation, but abnormal dispersion has the reverse impact. Section title: Numerical analysis Educational score: 2.613666296005249 Domain: biomedical Document type: Other Language: en Implement those computational equations to determine Dispersion of light . (8) β 2 = 2 c d d ω ( n e f f ) + ω c d 2 d ω 2 ( n e f f ) Here, β 2 represents dispersion parameter, c be the velocity of light, ω be the angular frequency. Section title: Numerical analysis Educational score: 3.9274802207946777 Domain: biomedical Document type: Study Language: en This section explore relation between light dispersion with the operating frequency of this suggested PCF sensor. The vertical axis to be considered for DP and horizontal axis considered for FR or P. As we made variation in FR or in P then corresponding change will occur in the DP. Here pink curve for ethanol and brown curve for methanol represents DP. Where at f = 3.2 THz the DP finds 0.2 ps/THz/cm and 0.14 ps/THz/cm for methanol and ethanol respectively. Fig. 8 Provides an analysis of dispersion in the THz range, showing how frequency impacts light speed and, consequently, the sensor's ability to distinguish between different analytes based on dispersion properties. Fig. 8 Demonstrate the influence of the Dispersion of light due to Frequency [THz]. Fig. 8 Section title: Numerical analysis Educational score: 4.126930236816406 Domain: biomedical Document type: Study Language: en This section's Table 1 compares the envisioned sensor's functionality to that of several already in consideration. We have mentioned the sensing analytes, operating frequency, RS, EML, NA and EA of those sensors with ours suggested sensor. From the table you can see that the sensing ability or RS of our intended detector is much better than that of others. It also having minimal EML that the mentioned sensors. Table 1 Performance study among currently available detector with our invented detector. Table 1 Ref. Analytes FR (THz) RS (%) EML (cm −1 ) NA EA (m 2 ) (R. ) Benzene 1.0 74.61 0.0138 – – Ethanol 1.0 74.53 0.0148 – – Water 1.0 74.17 0.0172 – – Water 1.0 73.20 – – 1.43 × 10 −7 Ethanol 1.0 76.44 – – 1.36 × 10 −7 Benzene 1.0 77.16 – – 1.35 × 10 −7 (S. ) Benzene 1.0 81.46 – – – (M.S. ) Ethanol 1.6 85.7 – 0.372 69800 (μm 2 ) (M.A. ) Benzene 1.7 89 0.028 0.42 – (D. ) Ethanol 2.0 95.21 0.0078 0.314 6.52 × 10 −8 Benzene 2.0 94.67 0.0083 0.307 6.84 × 10 −8 (M.E. ) Water 1.0 96.25 – – 6.84 × 10 −6 (μm 2 ) Present Research Methanol 3.2 95.72 0.0066 0.270 3.54 × 10 −8 Ethanol 3.2 97.55 0.0044 0.257 3.92 × 10 −8 Section title: Numerical analysis Educational score: 4.1864094734191895 Domain: biomedical Document type: Study Language: en Our planned chemical sensing to existing PCF monitors is the topic of a structured discussion that we are having. Table 1 provides additional background on our PCF research by detailing the main components of the current PCF type. The proposed methanol detection method using a heptagonal core PCF sensor demonstrates impressive performance when compared to existing works based on key factors such as Relative Sensitivity (RS), Effective Material Loss (EML), Numerical Aperture (NA), and Effective Area (EA). Achieving a maximum RS of 97.55 % for ethanol and 95.72 % for methanol at 3.2 THz, the sensor significantly outperforms other methods in the literature, such as those in (S. ) (M.S. ), where RS values range between 74.17 % and 85.7 % at lower frequencies (1.0–1.6 THz). These high RS values reflect the sensor's superior ability to detect slight variations in refractive index, which is critical for accurate chemical identification. Moreover, the low EML of 0.0066 cm⁻ 1 and high NA of 0.270 demonstrate superior signal transmission and improved light confinement compared to other techniques that report higher EML or lower NA values, such as in (M.A. ) (D. ). These advancements not only enhance the sensitivity and optical performance of the proposed sensor but also make it highly suitable for hazardous industrial environments, ensuring accurate methanol detection and reducing the risk of poisoning. Achieving such high sensitivity at 3.2 THz further underscores the sensor's advanced performance in the terahertz range, making it a highly effective solution for industrial monitoring and safety. The previous type is generally composed of a mixture of silicon dioxide and related materials and was particularly developed for constructing PCF measurement devices. Generally, fibers are shaped by the stack-and-draw process, which involves heating the mold before dragging it over a fiber. For specific purposes, perforations can be carved or engraved to assist with scanner engagement. A general function to enhance selectivity and sensitivity is to add functional coatings. Moreover, for individual sensors, detection mechanisms are essential such as microscopic particles present in cell walls (A.I. ) (C.G. ). Section title: Probable error calculation Educational score: 4.086392402648926 Domain: biomedical Document type: Study Language: en Our study is based primarily on simulations conducted using COMSOL Multiphysics, which involve complex numerical calculations that are highly precise. Unlike experimental data, these simulations are deterministic and do not contain the random measurement errors commonly encountered in experimental work. As a result, the use of error bars, typically used to reflect experimental uncertainties, is not as relevant in the context of our simulation-based research. However, we have incorporated numerical equations that allow for the estimation of potential errors for various parameters such as relative sensitivity, confinement loss, effective material loss, numerical aperture, spot size, and effective area. These equations provide a theoretical basis for approximating uncertainties in these parameters. The probable error can be calculated using statistical techniques, particularly during sensor calibration or testing. Section title: Probable error calculation Educational score: 3.8990395069122314 Domain: biomedical Document type: Study Language: en The process for calculating probable error involves the following steps. (1) Data Collection: Gather multiple readings from the sensor. (2) Mean Calculation: Compute the average (mean) value by summing all the readings and dividing by the total number of readings (K.S. ): (9) x ‾ = ( 1 / n ) ∑ i = 1 n X i (3) Standard Deviation (SD) Calculation: Measure the variation of the readings from the mean using the standard deviation formula (K.S. ): (10) σ = ( 1 / n ) ∑ i = 1 n ( X i − x ‾ ) exp ( 2 ) (4) Probable Error (PE) Calculation: Finally, determine the probable error by multiplying the standard deviation by a constant (K.S. ): (11) P E = 0.6745 × σ Section title: Application and limitation Educational score: 3.9897334575653076 Domain: biomedical Document type: Study Language: en To apply the heptagonal core PCF sensor for detecting alcohol in real commercial food samples, the process begins with collecting a variety of samples, such as alcoholic beverages or food with ethanol-based preservatives. After proper sample preparation, the sensor is calibrated using known concentrations of methanol and ethanol. The prepared samples are then analyzed with the sensor to detect and differentiate the alcohols based on their refractive index variations. The data gathered from the sensor is compared with conventional methods like gas chromatography to validate its accuracy and reliability in real-world applications shown in Fig. 9 . Finally, the results are documented to highlight the sensor's effectiveness and potential for improving alcohol detection in commercial food products. Fig. 9 Illustrates the workflow for applying the PCF sensor in detecting alcohol in food products, from sample preparation to data analysis. Fig. 9 Detection steps for analyzing alcohol in commercial food samples. Fig. 9 Section title: Application and limitation Educational score: 4.151986122131348 Domain: biomedical Document type: Study Language: en The limitations of THz PCF sensors in alcohol detection include challenges in precise fabrication, which can impact sensitivity and performance. Additionally, maintaining consistent sensor calibration in real-world conditions, such as varying temperatures and environmental factors, can be difficult. High costs of THz components and limited availability of commercial THz sources further restrict widespread adoption in practical applications. While this study demonstrates the sensor's high sensitivity and specificity in detecting methanol and ethanol under controlled conditions, future work could involve validating its performance with real commercial food samples, such as alcoholic beverages or foods preserved with ethanol-based ingredients. To ensure accurate readings in complex matrices, additional calibration may be necessary to account for potential interferences from food constituents, including sugars, proteins, and other additives. Experimental testing on real samples would provide valuable data on the sensor's robustness in practical applications, as well as insights into any sensitivity adjustments required. Key challenges include maintaining sensor calibration in variable environmental conditions and addressing the high costs and limited availability of commercial THz sources, which may affect widespread adoption. Incorporating such real-world data in future studies would further solidify the sensor's utility for alcohol detection in food safety applications. Section title: Conclusion Educational score: 4.245242118835449 Domain: biomedical Document type: Study Language: en The primary objective of this research is to develop a novel heptagonal core photonic crystal fiber (PCF) sensor capable of detecting both methanol and ethanol simultaneously with high sensitivity. Methanol is extremely harmful to living organisms, potentially causing serious illnesses such as cataracts, organ damage, or even death, while ethanol is generally safe for human consumption in moderation. Misidentifying methanol as ethanol can lead to severe toxicity and fatal consequences, making accurate detection vital for public safety. The proposed sensor, designed using COMSOL Multiphysics, Key metrics include a high relative sensitivity (RS) of 95.72 % for methanol and 97.55 % for ethanol, along with low effective material loss (EML) values of 0.0066 cm⁻ 1 and 0.0044 cm⁻ 1 , respectively. Furthermore, the sensor features optimized Effective Areas (EA) of 3.54 × 10⁻⁸ m 2 for methanol and 3.92 × 10⁻⁸ m 2 for ethanol, and small spot sizes (SP) of 2.12 × 10⁻⁴ μm and 2.28 × 10⁻⁴ μm, respectively. This high level of precision and performance in the THz range ensures reliable detection, which is critical for improving safety in industrial and commercial environments. The ability to detect both methanol and ethanol simultaneously at such high sensitivity distinguishes this sensor from existing technologies, contributing to enhanced public health protection and industrial monitoring. The proposed heptagonal core PCF sensor offers significant real-world applications, particularly in industrial monitoring and public safety. Its high sensitivity and precision in detecting methanol and ethanol make it crucial for preventing methanol poisoning in industries that handle alcohol-based substances. Additionally, it enhances safety by ensuring accurate chemical identification in environments where the risk of contamination or accidental exposure is high. For future research, efforts should focus on optimizing the fabrication process to make the sensor commercially viable. Investigating materials with higher thermal and mechanical stability could enhance durability, while scaling up production methods would enable widespread industrial use. Additionally, exploring integration with real-time monitoring systems could further expand its practical applications. Section title: CRediT authorship contribution statement Educational score: 0.998197078704834 Domain: other Document type: Other Language: en Most. Momtahina Bani: Data curation, Investigation, Methodology, Software, Writing – original draft. Khalid Sifulla Noor: Data curation, Investigation, Methodology, Software, Writing – original draft. A.H.M. Iftekharul Ferdous: Conceptualization, Project administration, Resources, Supervision, Validation, Visualization, Writing – review & editing. Md. Asaduzzaman Shobug: Supervision, Validation, Visualization, Writing – review & editing. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Other | biomedical | en | 0.999996 |
PMC11699085 | Section title: Introduction Educational score: 1.0786091089248657 Domain: other Document type: Other Language: en Higher education is a life-changing time for students, often young adults, who are developing their sense of self, role in society, independence and career trajectories. Certain groups, such as First Nations students , international students and those from lower socioeconomic backgrounds , are more likely to face additional challenges during this transition period. Section title: Introduction Educational score: 3.5641300678253174 Domain: biomedical Document type: Other Language: en In addition to the issues which arise during life transitions, medical training brings a unique set of challenges, which include high academic expectations, rigid course structures and exposure to a complex, sometimes distressing, clinical environment . As such, medical students may experience a negative impact on well-being, interpersonal relationships, quality of life and academic performance during their degree [ 4 , 6 – 8 ], especially when transitioning from pre-clinical into clinical years . Section title: Introduction Educational score: 3.804609775543213 Domain: biomedical Document type: Review Language: en One possible method to provide additional support for medical students is through mentoring programs [ 11 – 14 ]. In such programs, relationships are typically established between more experienced individuals (‘mentors’), and those more junior (‘mentees’), with the aim of promoting personal and professional development, as well as psychosocial support . Within medical schools, mentors for medical students can be faculty, senior or junior clinicians, or other students. Mentor selection may include factors such as academic performance, specialty, or sociodemographic backgrounds (e.g. cultural or religious ). Whilst faculty and clinician mentors bring more experience, peer mentors are typically considered more available and approachable . Peer mentors may be peers at the same level in their training, or near-peers, who have progressed academically beyond the mentee. In this review, we use the term peer mentoring to include both peers and near-peers for conciseness. Section title: Introduction Educational score: 3.92216157913208 Domain: biomedical Document type: Review Language: en Peer mentoring programs, especially where both mentors and mentees are medical students, are thought to benefit from the high level of ‘cognitive and social congruence’ that exists between students in similar educational environments . The shared understanding of academic frameworks, knowledge and interpersonal roles allows for the development of complex and comfortable mentor–mentee relationships . Furthermore, elements exclusive to student mentoring, such as the use of familiar language, similar social roles and an empathic understanding of the ‘student experience’, may provide benefits that faculty mentoring does not. A diverse student cohort, moreover, means that social congruence can extend to students from culturally and linguistically diverse backgrounds . Accordingly, one review found that the ‘comfortable’ learning environment established by peers has been highlighted as an important advantage over formalised teaching . Similar principles apply for ‘peer-assisted learning’ (or peer teaching). However, the difference is peer-assisted learning primarily targets academic goals, whilst peer mentoring prioritises wellbeing and support . Section title: Introduction Educational score: 4.106266498565674 Domain: biomedical Document type: Review Language: en Whilst mentoring in the medical profession is relatively common, there is also evidence to support mentoring of medical students. A 2020 qualitative study evaluating different university initiatives to reduce stress found that peer mentoring ‘effectively reduce(d) stress in medical students, and facilitate(d) their transition into medical school’ . A 2018 systematic review included five studies on near-peer mentoring programs, focusing on outcomes for first-year health professional (medical, allied health and nursing) students and reported personal development and psychosocial benefits for these mentees. In 2019, a large narrative review with 82 included studies on medical student mentoring also reported similar findings. This study showed mentees benefited from attainment of skills, knowledge and personal/professional development, whilst mentors improved in leadership and communication skills. However, the mentors in these studies were predominantly junior doctors, not medical students. Another systematic review focusing on the impact of mentoring on medical students from under-represented minority groups identified benefits for academic, research and career pathways. Finally, a systematic review on peer mentoring, specifically in Iranian medical schools, found benefits for both mentees and mentors. Section title: Introduction Educational score: 4.0873589515686035 Domain: biomedical Document type: Review Language: en Though the evidence for peer mentoring programs for medical students is promising, and several systematic reviews have been conducted to evaluate the utility of mentoring for medical students, none to date have specifically reviewed the benefits of near-peer mentoring by medical students, for medical students. This scoping review aims to determine the benefits and challenges of medical student peer mentoring programs, and identify elements for program success, accounting for differences in curriculum, program structure and mentor/mentee composition. Findings may inform future research and discourse and assist medical schools in the organisation and optimisation of their peer mentoring programs to benefit their students. Section title: Methods Educational score: 2.42334246635437 Domain: biomedical Document type: Review Language: en The scoping review was conducted in accordance with the Joanna Briggs Institute methodology for scoping reviews , and registered on the 6th of August 2023 with the Center for Open Science, 10.17605/OSF.IO/XEA63. The scoping review methodology was selected to map existing literature, both published and unpublished and to determine gaps with the aim of informing future research. Section title: Search Strategy Educational score: 3.9895670413970947 Domain: biomedical Document type: Study Language: en An initial limited search of Ovid MEDLINE, EMBASE and ERIC was undertaken using a search strategy developed with the assistance of a librarian. The text words contained in the titles and abstracts of relevant articles and the index terms used to describe the articles were used to develop a full search strategy with further librarian assistance. As ‘mentoring’ is not a MeSH term, and various phrasing is used to describe mentoring programs, the two-step development of the final search strategy was required. The following databases were searched: Medline, ERIC, EMBASE, Web of Science, WorldWideScience and the British Library on 22/1/2024. Keywords and MeSH terms used included medical student*, peer mentor* and medical education. Boolean operators (AND, OR, NOT) were used to refine search results. The search strategy was then adapted for other databases (see Appendix). The reference list of included studies and relevant reviews were screened for additional studies. Grey literature was searched using OpenGrey ( http://www.opengrey.eu ) and GreyNet ( https://www.greynet.org/ ). Section title: Inclusion and Exclusion Criteria Educational score: 3.6946918964385986 Domain: biomedical Document type: Study Language: en Inclusion criteria were as follows: Primary studies of any design published in English. Participants: Medical students undertaking a primary medical degree (undergraduate or postgraduate)—applicable to both mentor and mentee participants. Intervention: Peer or near-peer mentoring programs. Comparison: No program or different types of mentoring programs. Outcomes: Any that related to mentors or mentees including satisfaction with program, academic skills, professional skills and health and wellbeing, elements for peer mentoring program success and challenges of these programs. Section title: Inclusion and Exclusion Criteria Educational score: 1.826398491859436 Domain: biomedical Document type: Other Language: en Exclusion criteria were as follows: Doctors as mentors. Peer-assisted teaching and learning programs. Conference papers, abstracts and opinion pieces. Section title: Inclusion and Exclusion Criteria Educational score: 3.964952230453491 Domain: biomedical Document type: Study Language: en Two reviewers (AG/MK/CP and MR) independently screened titles and abstracts obtained from the search, excluding irrelevant citations, using Covidence. Full-text articles were subsequently retrieved and reviewed for final inclusion. Disagreements were discussed amongst three reviewers (AG/MK/CP, MR and LN) and resolved through consensus. The selection process was reported via Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram . Fig. 1 PRISMA flowchart outlining search results, screening and study inclusion process Section title: Data Extraction Educational score: 2.7360036373138428 Domain: biomedical Document type: Study Language: en Data were extracted by one reviewer (AG/MK/CP) and checked by a second (LN/MR). The following data were extracted: Study design and country. Participants: numbers of mentors and mentees, year of study in medical school. Interventions: program description, process of matching of mentees to mentors, duration, support provided for the program. Measurements, assessment time points and outcomes such as benefits, elements contributing to program success and challenges. Section title: Data Extraction Educational score: 2.168046712875366 Domain: biomedical Document type: Study Language: en The heterogeneity of the studies and variation in outcome measures (most of which had been self-developed) meant that pooling results for a meta-analysis was not possible. Section title: Reflexive Statement Educational score: 3.8951504230499268 Domain: biomedical Document type: Study Language: en The research question was ‘What are the benefits and challenges of medical student peer mentoring programs and what are the elements associated with their success?’ This question was derived from the authors’ experience as medical educators and medical students, namely, the challenge to develop and optimise a peer mentoring program for medical students which would best support their psychosocial, professional and academic needs. Therefore, the search strategy was developed in light of the authors’ joint interests. The two authors who primarily undertook the data extraction (AB, CP) were medical students at the time and participants of a peer mentoring program in their clinical school, and the extraction was verified by two other authors (MR, LN), one of whom (LN) had developed the clinical school mentoring program. The inclusion of a non-medical practitioner who had not been directly involved in the peer mentoring program (KF) ensured a level of rigour in data analysis and interpretation. Section title: Overview Educational score: 4.1770405769348145 Domain: biomedical Document type: Study Language: en A total of 1676 citations were identified through the initial search . Of these, 48 full-text studies were assessed for eligibility and 20 (two of the same program) met the inclusion criteria. Of the included studies, seven were cohort studies [ 13 , 14 , 17 – 19 , 27 , 28 ], seven mixed-methods [ 26 , 29 – 34 ], three qualitative and three cross-sectional [ 37 – 39 ] (Table 1 ). There was a total of 4591 participants with a range of 9–2362 participants in each study. When including only studies which specified year level of mentees/mentors, most mentees were in their first clinical year ( n = 898), whilst most mentors were near peers in either their ultimate or their penultimate year ( n = 224). Three programs had mentors and mentees from the same year level . In general, mentors and mentees were randomly matched, typically following a selection process for mentors. Six of the included studies considered specific characteristics (such as international students, being taught by the same faculty, personal relationships) when matching mentors and mentees. Mentoring groups were generally small, with one notable exception where a social media platform was used for large group mentoring . Twelve studies reported a component of peer teaching as part of the mentoring program [ 13 , 14 , 16 , 26 , 28 – 31 , 36 ]. Table 1 Summary of included studies Study (Country) Design Participants Intervention Assessment time points Measure Outcome Longitudinal programs Abdolalizadeh et al. 2017 (Iran) Qualitative Mentors—fourth year medical students (clinical, n = 6; non-clinical, n = 6) Mentees—first year medical students randomly selected from cohort (n = 36) Recruitment of mentors : volunteers Allocation of mentees to mentors : N/A; 2 mentors (one clinical, one preclinical) and 6 mentees per group Contact logistics : Contact made via telephone calls, email and face-to-face in varying frequency Training and orientation provided : Yes, were trained on purpose of mentoring and communication skill development Activities organised : Weekly inter-mentor sessions for idea sharing Duration of program : Academic year Conclusion of academic year Four focus groups administered to mentors and mentees Questions were regarding experiences in the program, perceptions of development, strengths and weaknesses of the program, and the quality of each component Length of each focus group was ~ 60 min. All meetings were recorded and transcribed Data analysis : Conventional content analysis • Mentors and mentees agreed on several characteristics that made a good mentor: patience, active contact and persistence • Mentees commented that their mentor played a role in their academic progress, mainly via discussions regarding study methods/techniques • Mentees benefitted from having both clinical and non-clinical mentors • The perceived independence of the program from the medical school was seen as a bonus for mentees and mentors • Diversity in communication methods was seen as a strength of the program, however most participants preferred face-to-face meetings • Mentors reported both professional and social development Altonji et al. 2019 (USA) Cohort study Mentors—2nd year medical students ( n = 112) Mentees—1st year medical students ( n = 190) Recruitment of mentors : Volunteers Allocation of mentees to mentors : Pairing done by student leaders (learning representatives in their second year, elected by their peers), no guidelines on pairing but was guided by personal relationships the leaders had to both mentors and mentees Contact logistics : Casual meetings at least once a month Training and orientation provided : Yes, large group training received once Activities organised : None Duration of program : Academic year Conclusion of academic year One survey and one focus group administered to mentees Mentorship Effectiveness Scale (MES)—twelve Liker-scale items to assess effective mentor behaviours, including perceptions of the benefits of the program, overall satisfaction and accessibility of contact of the mentor to the mentee A focus group was used to modify the survey to suit the needs of the study, and was non-evaluative ( n = 9, first years) Data analysis : Stepwise linear regression • Items that scored higher than 3.5 on the MES included the following: mentor was accessible (4.2 ± 0.99), approachable (4.41 ± 1.16), supportive and encouraging (4.36 ± 1.08), answered questions satisfactorily (4.13 ± 1.19), and suggested appropriate resources (4.09 ± 1.21), demonstrated expertise in an area of need (3.85 ± 1.16), provided useful and constructive critique (3.68 ± 1.43), provided guidance on how to succeed in medical school (3.83 ± 1.41), and provided useful advice on how to study (3.84 ± 1.26) • Overall satisfaction with the mentoring program was high (7.47 ± 2.45, out of 10) • Predictors to perceived satisfaction and benefit included the following: mentor knowledge, mentor advice on handling medical school, mentor providing guidance on professional matters, there was no statistically significant benefit to either male or female mentors; however, regular meetings and involvement were seen as a positive predictor • Results of focus group were used to modify the survey only and hence not separately reported Andre et al. 2017 (USA) Mixed methods Mentors—fourth year medical students (‘MiMs’) ( n = ~ 60) Mentees—first, second and third year medical students participating in the ‘Veritas’ mentoring program ( n = ~ 220/year level) Recruitment of mentors : Volunteer Allocation of mentees to mentors : All students randomly assigned to one of 20 Veritas groups upon enrolment; each group consisted of 11 students from MS1-MS4. 3 volunteer mentors allocated to each ‘Veritas’ group randomly Contact logistics : Group and one-on-one meetings, minimum once a month Training and orientation provided : None Activities organised : Weekly mentor meetings with Veritas director Duration of program : Academic year Conclusion of academic year with each new cohort Two self-developed surveys (piloted and refined prior to use) measuring effectiveness of peer-mentoring and perception of improved experience of medical school, administered to mentors and mentees Survey 1 (Veritas All Students Survey) asked mentees Likert scale questions regarding MiMs engagement with getting to know their mentees, assisting with rotation planning, stress management, guidance and advice, emotional support, the mentees preference for approaching MiMs over faculty mentors, and if the mentees saw MiMs a useful resource Survey 2 (Mentors in Medicine, or MiMs survey) asked the mentors questions about their perceived preparation in running meetings, providing guidance, personal and professional development, and their perceived success in their mentoring role Data analysis : Mantel–Haenszel Chi square • The findings showed that in general, peer mentors were able to provide advice about academic planning, psychosocial support, promoted interpersonal relationships, peer support and a safe space for mentees to discuss personal issues • Level of satisfaction varied year to year • In 2012 and 2013, 100% of mentors said they would volunteer again the following year • 71% of mentors felt sufficiently prepared in their role • Among first- and second-year mentees, there was an overall perceived benefit in performance year to year from 2011 to 2014 • Over the years there is a visible trend in improvement in satisfaction with the medical school experience via post hoc testing • Other up trending components of the survey included: discussion of professionalism questions, academic planning, future year planning, networking, peer support, relationships between classes, social supports and discussions of emotional issues that relate to the patient experience Behkam et al. 2022 (Iran) Cross-sectional Mentors: third/fourth year medical students Mentees: first year medical students Non-mentees: first year medical students Recruitment of mentors : Volunteers Allocation of mentees to mentors : Assigned based on gender, ethnicity, living place, scientific background. One-to-one allocation Contact logistics : Face to face meetings on a weekly basis Training and orientation provided : 3 day workshop on concept of mentoring, communication, program rules/expectations Activities organised : Weekly sessions centred around assisting new students with transition to medicine and aimed at improving their perception of educational environment Duration of program : Academic year During first year DREEM (Dundee Ready Education Environment Measure) tool (Persian translation) used to assess students’ overall perception of their learning environment Student responses were compared across the mentored and non-mentored groups and tested for significant differences Data analysis: T -test, ANOVA to compare means of quantitative variables. P < 0.01 used for statistical significance • 169 out of 190 study recruits (87 mentees, and 82 non-mentees) participated in data collection • Total DREEM score not different based on demographics • Mean DREEM scores of students with mentors not statistically different from those without • No DREEM item was significantly different across the two groups • More mentees stated that ‘there is a good support system for students that get stressed’ than non-mentees, P = 0.009 Chatterton et al. 2018 (UK) Cohort study Mentors—selected second and third year medical students ( n = 49) Mentees—first year medical students Recruitment of mentors: Initial year organised by Senior Tutors in collaboration with two student volunteers. Subsequent years was carried out by group of experienced peer mentors from the previous year Allocation of mentees to mentors: Certain groups matched accordingly (e.g. international student with international student peer mentor) Contact logistics: Peer mentors encouraged mentees to make contact when required, and contact made by peer mentors at various ‘high-stress’ points Training and orientation provided: 3 training sessions in total amounting to 6 h formal training over an 8-month period Activities organised: Informal welcome event Duration of program: Academic year Post second and third training session (mentors) Five-point Likert scale questionnaire evaluating peer mentor’s perception of whether the training sessions met their expectations, application of knowledge learned, confidence in their roles, perceived support, knowledge about where to sign-post mentees when indicated and overall questions about the quality of the trainers and materials/course content Post-third session: similar to post-second training session questionnaire, but was amended to incorporate questions eliciting specific feedback on new issues discussed and not covered in former session (resilience, mental health and revision/ study skills) • Both sessions were rated highly with a mean (± standard deviation) session of 4.37 (± 0.21) after the second training session from 29 responses, and 4.33 (± 0.38) following the third session from 32 responses • Following the second session, the question rated highest was ‘I feel that I will be supported in my role as peer mentor’ with a mean score of 4.72 and the question rated lowest was ‘the training met my expectations’ with a mean score of 4.03 • Following the third session, the question rated the highest was ‘The trainer was knowledgeable’ with a mean score of 4.72, and the question rated the lowest was ‘My own revision strategy will change in light of the station on revision/study skills’ with a mean score of 3.13 Cho and Lee 2021 (Korea) Mixed methods study Mentors—either in the same year level as their mentee, or two academic years above Mentees—preclinical second year (PY2), first year (Y1) or second year (Y2) medical students Total n = 67 participating in peer-mentoring program; breakdown unspecified Recruitment of mentors: Volunteer Allocation of mentees to mentors: Choice to pair themselves or school to pair mentor and mentee Contact logistics: Meeting approximately 4 or more times per semester Training and orientation provided: At least 2 h of education on mentoring, rules to follow and appropriate communication and feedback skills Activities organised: None Duration of program: 2 years Conclusion of program Quantitative: survey assessing general information regarding program implementation (how often students participated; how mentors and mentees would meet; how many times, where, and at what times mentors and mentees would meet) and appropriateness (satisfaction with the program, purpose for participation and mentors’ role). Program satisfaction and appropriateness were answered using the Likert scale of 1–5 (with 1 being ‘not at all’ and 5 being ‘very high’) Qualitative: open-ended survey questions (regarding benefits and outcomes gained by both) and focus group interviews (1–2 h of probing questions: (1) why and how students participated in the mentoring program, as well as how they felt or what they thought about the program; (2) the personal experiences of students; and (3) the significance of their participation. Also included discussion regarding what more was needed to improve) Data analysis: Mann–Whitney U -test was used to compare differences in continuous variables between groups due to small sample size • Program implementation: 84% face-to-face meetings, 74% used text messages, 64% had meetings for 1–2 h, 21% had meetings for less than an hour • Participant satisfaction and evaluation of program: mentors rated 3.6 (± 0.5) and mentees rated 3.8 (± 1.0) • Purpose of students’ voluntary participation and role of mentors: most common answer for both mentors and mentees were ‘teaching assistance for test-taking strategies and guidelines’ followed by emotional support • Qualitative outcome and mutual benefits: improved grades for mentees’, an increased willingness and motivation to study, improved lifestyle patterns, emotional support. Specific to mentees’: improving interpersonal relationships and obtaining support. Specific to mentors: better understanding of previously learnt content, sense of responsibility • Qualitative negative experiences: one mentee response ‘feeling pressure’, and mentors ‘not improving mentees’ learning habits or attitudes nevertheless continuous asking improvement’, ‘not doing homework’ and ‘not contacting or requesting in advance’ • Suggestions for improvement from both mentees and mentors: ‘specific guidelines on how to do’, ‘training and education for mentees’ and ‘appropriate matching between mentor and mentee’. Mentors specifically suggest knowing the characteristics and tendencies of both mentee and mentor, the mentee must have a clear purpose when they participate, and the mentee’s voluntary participation is essential Fleischman et al. 2019 (USA) Cross-sectional study Mentors—77 fourth year medical students in the formal mentoring program (‘Cicerone’) Mentees—first and second year medical students; number not specified Recruitment of mentors: Not specified Allocation of mentees to mentors: Defined by programs that ‘formally and thoughtfully assign mentor to mentee’. 4th year medical students assigned to 2nd years, and 3rd year students to 1st years Contact logistics: Not specified Training and orientation provided: Not specified Activities organised: Not specified Duration of program: Not specified Conclusion of academic year Survey including categorical options and open-ended questions. Respondents who participated in Cicerone peer mentoring program were specifically compared to those who did not participate in any formal mentoring A second purely descriptive analysis was performed including only those who did not participate in any mentoring to understand their motivation for not participating A third analysis of only Cicerone (formal peer mentoring) to assess their experience Data analysis: Simple statistics used, including Fishers exact and chi-squares for categorical variables, and t tests and Kruskal–Wallis for continuous variables • 60% response rate (107/178); 42 participated in Cicerone program (77% response rate), 17 mentored in other programs, and 48 non-mentors responded • Non-mentors did not participate in the mentoring program due to: not knowing about program (69%), not having time (26^) and not believing it was useful (23%). Men were more likely than women to cite ‘not knowing about the program’ and ‘did not believe it would be useful’ • Cicerone mentors were twice as likely to believe being a mentee was beneficial in medical school. 75% of mentors felt it was a worthwhile experience • Mentors were 4 times more likely to believe that being a mentor in an SSM program was valuable and 83% stated they would mentor again • Career choice was discussed by 79% of pairs, and 42% mentors felt more positively about their career choice Nebhinani et al. 2020 (India) Cohort study Mentors—undergraduate medical students in their 3rd, 4th and first half of 5th year, or faculty members Mentees—undergraduate first and second year medical students ( n = 162) Recruitment of mentors: Volunteer Allocation of mentees to mentors: Either peer or faculty mentor randomly assigned to 2–4 mentees Contact logistics: Encouraged at least one mentorship meeting every fortnight Training and orientation provided: Guidelines for mentees and mentors Activities organised: Discussions Duration of program: 8 months Not specified; questionnaire distributed to ‘receive feedback for ongoing mentorship program’ Semi-structured questionnaires, which involved survey items and questions assessing perceived benefits and qualities of mentors, barriers in mentorship meetings, commonly discussed topics in mentorship meetings, and the role of faculty mentor and their relationship Data analysis: Comparison between the groups have been done using chi-square test and t -tests for categorical and continuous variables respectively • Over the 8-month period, mean number of meetings were 4 with faculty mentor and 11 with peer mentor • For both the faculty member and peer mentors, mentees commonly reported that their qualities included being understanding, being supportive and having a helping attitude • The most common barriers faced with faculty members include difficulty synchronising meeting times, students’ lack of time or no interest from students • The most common barriers faced with peer mentors include difficulty synchronising meeting times, mentors’ lack of time and then students’ lack of time Commonly discussed topics with both faculty and peer mentors include education in general, life as a medical student and work-like balance related issues *Neufeld et al. 2020 (Canada) Cohort study Mentors—second year medical students as ‘instructor-mentors’ n = 17 Mentees—first year medical students as ‘learner-mentees’ n = 38 Recruitment of mentors: Voluntary Allocation of mentees to mentors: 2 s year mentors matched with 2 or more first year students weekly Contact logistics: Weekly from October to April with exception for holidays and exams Training and orientation provided: Mentors received only general instructions prior to mentoring without any specific prerequisite training Activities organised: ‘PULSE’ (Peers United in Leadership and Skills Enhancement) sessions; topics coincided with students’ curriculum and progressed from basic history taking and physical exams, to procedural (e.g. otoscope) and interpretative skills (e.g. chest x-ray), to problem solving (e.g. formulating differentials, investigations and management plans) and presenting cases Duration of program : 6 months Within 3 months (April–June) post-PULSE (Peers United in Leadership & Skills Enhancement) sessions General feedback form, and adapted 6-item Learning Climate Questionnaire which measures perceived autonomy support • First year medical students attended an average of 2–3 sessions • PULSE helped reduce performance anxiety around OSCE’s, not only providing ‘a safe and relaxing learning environment, but comradery and professional relationships as well’ • Mentors ‘were incredibly helpful and had a different perspective than instructors, which made it easier to ask questions’ and ‘supportive feedback and non-judgmental environment’ *Neufeld et al. 2021 (Canada) Mixed methods study Mentors—second year medical students as ‘instructor-mentors’ n = 37 Mentees—first year medical students as ‘learner-mentees’ n = 53 Recruitment of mentors: Voluntary Allocation of mentees to mentors: 2 s year mentors matched with 2 or more first year students weekly Contact logistics: Weekly from October to April with exception for holidays and exams Training and orientation provided: Mentors received only general instructions prior to mentoring without any specific prerequisite training Activities organised: ‘PULSE’ (Peers United in Leadership and Skills Enhancement) sessions; topics coincided with students’ curriculum and progressed from basic history taking and physical exams, to procedural (e.g. otoscope) and interpretative skills (e.g. chest x-ray), to problem-solving (e.g. formulating differentials, investigations and management plans) and presenting cases Duration of program : 6 months Conclusion of academic year 3 validated Likert-type surveys: • LCQ (Learning Climate Questionnaire): 6-item scale measuring learners’ perspective of the autonomy supportiveness of their mentors • W-BNS (Basic Need Satisfaction at Work Scale): 21-item scale measuring workplace need satisfaction • PCS (Perceived Competence Scale): 4-item scale assessing feelings of competence in a given task, referring to learning or teaching clinical skills in PULSE sessions Data analysis: Cronbach’s alpha values for each scale to calculate reliability Linear regression used to assess learner perception of how PULSE’s learning climate impacted need satisfaction and how need satisfaction impacted perceived competence in learning. Further analysis of how each of the autonomy, competence and relatedness satisfaction subscales predicted their perceived competence in learning as separate independent variables Linear regressions used to assess mentor perceptions of how overall need satisfaction in PULSE impacted perceived competence in teaching, followed by how need satisfaction subscales predicted perceived competence in teaching • Both groups’ mean scores for autonomy, competence and relatedness supported high levels of need satisfaction • PULSE’s learning climate positively related to learners’ overall need satisfaction ( R 2 = .39, p = .01) • When overall need satisfaction was entered into the regression as the independent variable, it positively related to perceived competence in learning the material ( R 2 = .32, p < .05) • Mentors’ overall need satisfaction in PULSE positively related to their perceived competence about teaching the material • Both mentors and mentees found PULSE sessions highly supportive to their autonomy, competence and relatedness; this corresponded with greater perceived competence about learning and teaching of clinical material Shafiaai et al. 2020 (Malaysia) Mixed methods study Mentors—‘senior year medical students’ ( n = unspecified) Mentees—undergraduate second year pre-clinical medical students Recruitment of mentors: Elected through an interview for their excellent communication and inter-personal skills and have achieved excellent results in all course-related examinations with a ranking of upper third quartile in their cohort of students Allocation of mentees to mentors: Not specified Contact logistics: Weekly basis Training and orientation provided: Two-day Peer-Assisted Study Sessions (PASS) leaders training is conducted by a certified trainer-supervisor for PASS program Activities organised: 1 hourly weekly based integrated learning session through problem-solving and active discussion regarding various topics anatomy, biochemistry, physiology and clinical skills, etc Duration of program: One 12-week semester Baseline and at the end of 12-week program (questionnaire) Focus group discussion 1 year after completion of 12-week program Validated questionnaire (5-point Likert scale) which included 12 items with focus on establishing level of communication skill and pedagogical skill Structured focus group interview exploring whether or not participation in the PASS program as peer leaders helped in developing skills required to become a successful doctor in the future from participant’s point of view • On completion of PASS program, peer leaders reported an increase in oral and written skills to engage with junior students, and skills to develop interaction and collaboration • Peer leaders reported a significant increase in leadership skills and teamwork, stress and time management skills, interpersonal and critical thinking skills, ability to create an effective learning environment, ability to learn new skills, problem-solving and innovative thinking, facilitate teaching sessions and ability to develop independent learning amongst their students • Qualitative analysis revealed 2 main themes: personal growth and professional growth • Within the theme of Personal Growth, 4 skill subthemes were identified: communication, leadership, learning and pedagogical skills Within the theme of Professional Growth, 4 subthemes were identified: administrative, experience, responsibility and time management Singh et al. 2014 (India) Cohort study Mentors —a mix of second, third, and fourth year volunteer medical students ( n = 57). Plus, faculty supervisors ( n = 52) Mentees —first year medical students ( n = 148) Recruitment of mentors : Volunteers Allocation of mentees to mentors: Randomly to 52 groups; one mentor and one faculty supervisor for to three mentees Contact logistics: Meetings, frequency not specified, method of contact not specified Training and orientation provided: None Activities organised : 2 ‘open house’ meetings with entire mentoring cohort Duration of program: Academic year Conclusion of academic year Two self-developed questionnaires were administered to mentors and mentees Questionnaire 1: to mentees, questions focused on the amount and quality of the contact with mentors Questionnaire 2: to mentors, focused on what they gained from the program, and the barriers that affected them Data analysis : Chi-square for categorical variables, student unpaired t -test for continuous variables • Average contact time between peer mentors and mentees increased when compared with contact time between mentees and faculty mentors • Peer mentors reported benefits to them from engagement in the program; particularly improvement in problem-solving, responsibility, confidence and counselling, dual-way mentoring Taylor et al. 2013 (USA) Cohort study Mentors—second year medical students, in a ‘teaching academy fellow’ role ( n = 28) Mentees—first year medical students ( n = 96) Recruitment of mentors : Volunteers Allocation of mentees to mentors : One mentor to four mentees; mentors assigned to groups taught by the same faculty as in their first year when possible Contact logistics : Meetings twice a week Training and orientation provided : Yes, 2-h orientation Activities organised : Group discussions, wellbeing checks Duration of program : Academic year Academic years ending mid 2009 mid 2010 Immediately post orientation (mentors) 2-months post orientation workshop (mentors) Conclusion of academic year (mentees) Non-validated surveys administered to mentors and mentees The first after the orientation workshop received by the mentors, and then 2 months into the program. Surveys aimed to examine the application of skills taught to mentors in orientation workshops, as well as student satisfaction as mentors Data analysis : Not specified • Evaluation of orientation: Reported increase in confidence in ability to provide adequate and constructive feedback ( p < .001) • Evaluation of whole academic year program: 94% of TA mentors suggested the orientation workshop be continued in years to come, with suggestions on how to improve made • Majority of mentees were satisfied with the quality of feedback, reported confidence in performing medical interview increased after mentoring sessions Yang et al. 2021 (USA) Qualitative Mentors—third and fourth year medical students randomised to Education Centered Medical Home (ECMH—a team-based clerkship program consisting of students across all 4 year levels) Non-mentors: third year students randomised to the Individual Preceptorship stream (IP; one-on-one clerkship program pairing a student with a physician) Mentees—students from all four year levels participating in the ECMH program Recruitment of mentors: Students randomly assigned to ECMH stream Allocation of mentees to mentors : students randomly assigned to the ECMH stream. Group size not specified Contact logistics: Students attended ECMH clinic 26 times throughout third and fourth years Training and orientation provided: None Activities organised : None Duration of program: 4 years 3 months into the semester of third year One-to-one semi-structured interview with M3 mentors using an interpretivist paradigm. Interview questions included: What opportunities have you had to teach your peers, what opportunities have you had for your peers to teach you, can you tell me about a time when you have served as a role model or mentor for other medical students and in general, how does it feel to be an M3 in clinic now, thinking back to when you were an M1? Data analysis: two cycle-based inductive approach to coding and analysis • Derived three main themes: (1) diversity of peer teaching and mentoring opportunities, (2) transitioning one’s role from learner to teacher and (3) personal and professional development • Whilst participants from both clerkships participated in peer teaching and mentoring experiences, ECMH students described more opportunities to interact with students across all years of medical school training, noting that ‘getting that guidance and in turn being able to teach is a valuable experience’ • ECMH students further perceived the responsibility of creating a comfortable learning environment for others • Students from both clerkships (ECMH and IP) reflected on ‘learning through teaching’, that teaching served as a reaffirmation of the knowledge they gained, and that teaching experience contributed to their personal and professional growth • ECMH students further described a heightened sense of self-confidence and fulfillment Yusoff et al. 2010 (Malaysia) Cross-sectional study Mentors—select second year medical students—‘BigSibs’ Mentees—first year medical students n = 449 students; breakdown unspecified Recruitment of mentors : Selection based on academic performance, ‘BigSib’ Allocation of mentees to mentors : Not specified Contact logistics : Monthly 2-h meetings, method of contact not specified Training and orientation provided : None Activities organised : Meetings, indoor games, workshops, treasure hunts, hiking, public speaking, picnics, outings Duration of program : Academic year Conclusion of program Validated questionnaire administered to mentors and mentees, with two domains measuring perception of the program in promoting campus life, mental health and wellbeing and confidence and respect of peers Data analysis : Chi-square goodness of fit test for categorical variables, Pearson chi-square to establish relationships and multiple logistical regression for individual effects of targets • Majority of mentees felt as though the program did little in aiding communication between students and lecturers, and that the aims and objectives of the program were not made clear to them • Mentees (60%) felt that the program improved soft skills, professionalism • Less than half (45.9%) perceived the program as effective, but overall, it was perceived in a positive light • Program (from mentees perspective) was seen to aid in study skills, stress reduction, improve confidence and assist in adjustment to campus life Focused programs Barker et al. 2012 (UK) Mixed methods study Mentors—fifth year medical students ( n = not specified) Mentees—first year medical students ( n = not specified) Recruitment of mentors : Volunteer Allocation of mentees to mentors : Random Contact logistics : Mentees expected to contact their mentor prior to the day Training and orientation provided : None Activities organised : Hospital orientation day (HOD) for early clinical exposure. Pre-visit planning sheet (mentees), orientation to the hospital environment, mentees to join fifth years in a teaching session Duration of program : One day Immediately post intervention (survey) One-year post intervention (focus group) One questionnaire and a focus group administered to mentees Non-validated questionnaire, consisting of questions regarding the organisation of the HOD. The answers were reported, and further, used to guide the focus groups the following year Focus groups (number of participants ranged from 4 to 5), semi-structured, digitally recorded and transcribed Data analysis : Not specified • Mentees reported little to no fear regarding entering clinical placement, which was attributed to work experience, pre-visit contact and following the fifth year as key factors • Mentees found positive interactions with clinical staff and patients reassuring • Mentees saw the day as an insight into what their future in clinical medicine would look like and was associated with improved motivation • Mentees gained an understanding of the culture of the hospital and clinical learning and commented on the self-directed and autonomous learning styles of the fifth years • Mentees saw the day as valuable in facilitating discussions with clinical students Perception of the day was deeply affected by the ‘quality of the fifth year’. Characteristics that had made a quality mentor in this context included: ‘friendly’, ‘helpful’, ‘interested’, ‘proactive’ and ‘cheerful’ Choudhury et al. 2014 (USA) Cohort study Mentors—fourth year medical students ( n = not specified) Mentees—first year medical students ( n = 77) Recruitment of mentors : Volunteer Allocation of mentees to mentors : Random Contact logistics : Mentees joined Mentors at one of four student run clinics Training and orientation provided : None Activities organised : Interview skill practice, patient interactions, examination practice, case presenting, clinical note writing Duration of program : Duration of clinical placement; not specified Immediately post intervention Questionnaire administered to mentees, consisting of questions regarding frequency of volunteering, improvement in clinic-associated skills, and the role fourth year mentors played in improvement. General questions inquired about the fourth-year presence, role and impact on mentee comfort Data analysis : One-sample Wilcoxon sign-ranked median test and ordered logistic regression • Mentees reported increased comfort with patients in clinic, and increased level of mentorship due to mentor presence • Mentees did believe the role played by fourth year mentors was different to the role played by attending physicians but found that fourth year presence enhanced mentee interactions at a comparable level • The perceived improvement was independent of which clinic the mentees attended, as well as the number of clinics volunteered at, frequency of volunteering or the number of mentors at the clinic • Logistic regression showed significant association between mentor presence and self-reported improvement in physical exam skills, and case presentation skills at one clinic site (however, no association with patient interviewing and note writing skills), but not at the other three sites Lynch et al., 2022 (US) Mixed methods Mentors—‘clinical-level students’ who had already taken the USMLE step 1 (M3, M4) n = 75 (breakdown unspecified) Mentees—pre-clinical students or M3s yet to sit the USMLE step 1 (M2, M3); n = 125 (breakdown unspecified) Recruitment of mentors : Volunteers Allocation of mentees to mentors : Random; opt-out program Contact logistics : Mentors to contact mentees via email and explain program, offer frequency of meetings Training and orientation provided : Mentors attended a mandatory 1-h training session outlining the ‘Step Sibling’ program aims—told NOT to provide academic support Activities organised : Mentors encouraged to organise wellbeing checks monthly Duration of program : October 2020–March 2021 (beginning of year to USMLE Step 1 test) Immediately post USMLE Step 1 exam Questionnaire aimed at ‘elicit[ing] student reflections on the program’s effect on their stress levels and overall wellness and to seek feedback for future improvements to the program’ Data analysis: Response data evaluated for trends in agreement/disagreement Qualitative thematic analysis for comments • 91% of mentees took exam after participating in program • 77% of mentees felt they were being contacted sufficiently by their mentors; 56% of mentees agreed that they found the program helpful; 53% of mentors agreed that they felt they were helpful • Majority of mentors (70%) and mentees (62%) agreed that ‘sharing perspective and experience was helpful’; sharing resources described as least helpful role of mentors • Most mentees and some mentors expressed desire to offer academic support. Some mentees reported being confused about the aims of the program • Majority of mentees ‘found the program helpful in decreasing stress’. A minority did not find peer mentors helpful, citing ‘already having existing mentors or supports in place.’ • Future program would involve information session for mentees to outline aims of program and the intention to provide wellbeing support only Pinilla et al. 2015 (Germany) Mixed methods study Mentors/mentees—First and second preclinical year medical students in Facebook groups for their respective year level First years n = 1149 Second years n = 1213 Recruitment of mentors: No formal recruitment of mentors, who were existing Facebook users present in year-level groups Allocation of mentees to mentors: To be accepted into the Facebook group by people already in the group Contact logistics: no formal contact organised; posts and comments as needed in group Training and orientation provided: None Activities organised: Posts and comments in two preclinical year Facebook groups Duration of program : 5 months At the beginning of each semester, time periods directly correlating to critical written and oral exams, and between examination periods Analysis of all posts and comments in the two preclinical year Facebook groups using a social constructivist perspective to identify emerging peer-mentoring themes that are relevant for undergraduate medical students and reflect social norms, values and needs of medical students in this context. Anchoring examples were defined for each peer-mentoring subcategory and the final coding scheme was applied to three critical weeks of each preclinical year with particularly high or low posting frequency, as well as at the time of high-stakes exams Frequency of peer-mentoring related elements in posts and comments was reported Two focus groups with medical students enrolled in different semesters were conducted • The preclinical year 1 (PCY1) Facebook group and preclinical year 2 (PCY2) Facebook group had significant number of individuals being members of both Facebook groups, with enrolled PCY1 and PCY2 students being 950 and 966 respectively • Most common categories for PCY1: social activities, study related topics and resources. Most common categories for PCY2: social activities, study related topics and knowledge/skills • More complex peer-mentoring elements such as empowering and fostering personal development seem to be underrepresented in these groups From the focus groups, 3 major themes emerged: similarity in experience and rank, pool of skills/experiences/resources within a group and empowerment and emotional support Prunuske et al. 2019 (USA) Qualitative study Mentors—second year Native American and Alaskan Native medical students ( n = 9) Mentees—First year Native American and Alaskan Native medical students ( n = 40) Recruitment of mentors : Selected based on interpersonal skills and academic performance. Mentors were paid an hourly salary Allocation of mentees to mentors : 1 mentor to 4.5 mentees, allocation method not specified Contact logistics : Daily interaction via activities coordinated by program organisers Training and orientation provided : None Activities organised : Clinical skills, problem-based learning, microbiology labs and faculty lectures Duration of program : 4 weeks for each year however program ran for 5 years with 5 different cohorts 6 months after program conclusion Semi-structured interview administered to mentors, comprising 19 questions regarding what they gained, what could be improved and what sort of guidance was provided to the mentees Data analysis : Not specified • Role was described by mentors as beneficial in several ways: emotional/social support, academic support and give an insider view of medical experience • Social congruence was a common theme, under comments such as ‘you remember what it feels like’ etc • Mentors noted that small cohorts and frequent meetups strengthened the relationship between mentee and mentor • Mentors also found the experience beneficial to consolidating their knowledge and skills, as well as reinforcing a commitment to rural First Nations health * Two reports of the same program Section title: Overview Educational score: 3.494884729385376 Domain: biomedical Document type: Study Language: en Peer mentoring programs could broadly be divided into two types. Fifteen studies (two describing the same program) were ‘longitudinal’ programs, aimed at establishing mentor–mentee relationships to offer ongoing support over a longer period, such as an entire academic year. The remaining five studies were more ‘focused’—generally shorter-term programs with the intent of providing mentorship during significant moments for mentees, such as transition to clinical placement, medical school orientation or exam periods. Accordingly, where programs were named, these names generally reflected the goals—‘BigSibs’ and ‘Mentors in Medicine’ for longitudinal programs, compared to ‘Step Sibling’ , which focused on providing (non-academic) support for the USMLE Step 1 exam. Section title: Overview Educational score: 3.8254077434539795 Domain: biomedical Document type: Study Language: en In terms of outcome measurements, 17 studies used quantitative tools, mostly self-developed (piloted or validated in four studies ). Three studies used standardised and validated tools: Mentorship Effectiveness Scale , DREEM and LCQ, W-BNS and PCS . Assessment timepoints were short-term (start and end of the programs). Only one study assessed additional longitudinal outcomes (12 months post-program). Results were analysed for statistical significance in 12 studies [ 18 , 19 , 26 – 30 , 34 , 36 – 39 ]. Section title: Overview Educational score: 1.6738423109054565 Domain: other Document type: Other Language: en Outcomes for longitudinal and focused programs respectively are presented in the following section, outlining benefits, elements for program success and challenges. Section title: Study Characteristics Educational score: 2.841277599334717 Domain: biomedical Document type: Study Language: en Of the 20 included studies, 15 described longitudinal near-peer programs. Thirteen spanned the duration of the academic year, whilst one was semester-long (12 weeks) and another, 4 years long . Two programs were directed at preclinical students who were transitioning to clinical placement . The remaining 13 studies included first or second year students as mentees, and two involved students across all year levels . Section title: Study Characteristics Educational score: 2.7523422241210938 Domain: biomedical Document type: Study Language: en Mentors were typically senior students in their second (five programs) or fourth year (two programs), or students from multiple year levels (six programs). Two programs also involved doctors as mentors . One program paired mentees with either mentors in the same year level as the mentee, or two academic years senior . The other program paired student and faculty mentors . The program initially commenced with faculty mentors only, but added student mentors following feedback that mentees were reluctant to meet their mentors. Subsequently, students met more often with both peer and faculty mentors . In contrast, a study by Yang et al. compared the experiences of mentees who had received mentoring from peer mentors to those who had received mentoring on a one-on-one basis with a physician; there were no reported barriers to engagement; however, there was a notable component of teaching in this mentoring program, and attendance was mandated . Section title: Benefits Educational score: 3.2008907794952393 Domain: biomedical Document type: Study Language: en Studies assessed the impact of their programs on either the mentors, mentees or both. Seven studies assessed outcomes measures for both, whilst three assessed mentee outcomes and three mentor outcomes. Of the seven studies which assessed outcomes for both, all studies reported positive outcomes in confidence, perceived learning environments and psychosocial wellbeing for both mentees and mentors. Where peer mentors or physician mentors were compared, there was no difference in reported mentee benefits . Section title: Benefits Educational score: 3.485358715057373 Domain: biomedical Document type: Study Language: en Positive outcomes for mentees were academic development, psychosocial wellbeing and communication skills. Five studies reported mentees felt more confident with their academic skills due to skills gained from mentors, such as academic planning and study techniques . Mentees also perceived the learning environment more positively and reported improvement of social, interpersonal and clinical communication skills . Two studies found improved psychosocial and emotional peer support for mentees, and one study showed mentees were more likely to feel they had a good support system in times of stress. The provision of a ‘safe space’ for mentees was highlighted in three studies . Another study emphasised that mentees felt more competent and autonomous as learners in the learning climate fostered by near-peer mentors . Section title: Benefits Educational score: 1.7881972789764404 Domain: other Document type: Other Language: en Mentor outcomes were academic and interpersonal skills gained from mentoring, and overall satisfaction with mentoring. Mentors perceived improvement in professional skills, such as responsibility, leadership and communication ; moreover, they felt satisfied with their experience , and more confident when learning and teaching . Section title: Expectations of Regular Contact Educational score: 2.7193691730499268 Domain: biomedical Document type: Study Language: en Although program structure varied, all expected regular contact, with seven programs [ 14 , 29 – 31 , 35 , 37 , 39 ] outlining minimum requirements for mentor/mentee contact frequency, ranging from twice weekly , to weekly , and at least monthly . The only program where contact was mandated was the study by Yang et al. . Most studies did not report frequency of contact and it is unclear how often mentors and mentees met. Two of the studies found that synchronising meeting times was a common barrier; however, this was less of a barrier with peer mentors than with faculty mentors . Section title: Face-to-Face Communication Educational score: 1.5186153650283813 Domain: other Document type: Other Language: en Students reported using a variety of methods including face-to-face , text messages and email, with face-to face reported as most beneficial in one study and most utilised in another . Section title: Clear Agendas Educational score: 1.8521355390548706 Domain: other Document type: Other Language: en Nine programs encouraged student-driven agendas for mentor–mentee meetings whilst five programs were more prescriptive, focused around clinical topics , or non-clinical academic topics such as professionalism and social supports . One study further facilitated the program though the organisation of social activities . Section title: Orientation and Training for Mentors Educational score: 1.6369752883911133 Domain: other Document type: Other Language: en Orientation and training was provided for mentors in seven studies . This generally involved outlining the purpose of mentoring and program expectations , communication, leadership and/or interpersonal skill development . These ranged from one-off sessions to more intensive 2-day , 3-day or multi-session training . Section title: Orientation and Training for Mentors Educational score: 2.16329026222229 Domain: biomedical Document type: Study Language: en Overall, training was viewed favourably. Mentors reported an increased ability to provide constructive feedback post orientation , and that training improved their communication, leadership and interpersonal skills, in both personal and professional domains . In one study with no orientation or training, mentors reported that they would have benefited from clearer aims, objectives and guidelines , and further, mentors in one study reported that more than one session was required . Section title: Challenges Educational score: 1.6829866170883179 Domain: other Document type: Other Language: en The balance between training and overload of mentors was important, as mentoring and training was on a voluntary basis . Matching mentees with mentors intentionally was received positively. However, the authors of one study noted that this may be more logistically intensive, and felt more evidence was needed before such measures were implemented . Section title: Study Characteristics Educational score: 2.488044500350952 Domain: biomedical Document type: Study Language: en Five studies described focused mentoring programs with targeted aims [ 16 , 28 , 32 – 34 ]. There was more heterogeneity across these studies in terms of program structure and setting and aims. The shortest of these was 1 day , targeted at hospital orientation, and the longest 6 months, targeted at support for the USMLE Step 1 exam . One study provided a single training session for mentors . Section title: Benefits Educational score: 2.1411445140838623 Domain: biomedical Document type: Study Language: en For programs with a clinical focus, outcomes were measured through self-developed questionnaires, which found positive findings in increased comfort, reduced fear and improved understanding of self-directed learning styles or clinical skills . However, these questionnaires were not externally validated. The First Nations peer mentoring program found that the program reinforced the commitment of mentors to rural First Nations health . Section title: Benefits Educational score: 1.5080323219299316 Domain: other Document type: Other Language: en The ‘Step Sibling’ program also reported positive overall findings, with general agreement from both sides that the sharing of perspectives and experiences had been helpful. Mentees reported that the program had decreased their stress. It was also reported that mentees felt the least useful role of mentors was in sharing resources. Section title: Clear Focus Educational score: 2.131861448287964 Domain: biomedical Document type: Other Language: en Of the five programs, three had a clinical focus, designed to familiarise mentees to a clinical environment and the teaching activities that occurred in that setting. Of these, one was developed specifically for First Nations students . In contrast, the ‘Step Sibling’ program was more exam-focused, specifically designed to offer psychosocial support to students undertaking the USMLE step one exam. Section title: Matching of Mentors and Mentees Based on Additional Shared Characteristics Educational score: 1.6698843240737915 Domain: biomedical Document type: Other Language: en This was an important factor especially for under-represented groups . Section title: Remuneration Educational score: 1.0319513082504272 Domain: other Document type: Other Language: en The program for First Nations students reported that mentors were paid a salary . Section title: Challenges Educational score: 1.395101547241211 Domain: other Document type: Study Language: en Interestingly, one study utilised social media as a means for mentoring for large groups of students . Social interactions within a year-level were observed in two large first and second year-level Facebook groups. Thematic analysis of posts identified peer-mentoring themes. However, whilst students appreciated the experience and pool of resources, complex peer-mentoring elements such as empowerment and fostering personal development were absent. Section title: Discussion Educational score: 4.0305047035217285 Domain: biomedical Document type: Review Language: en Our scoping review included 20 peer mentoring studies where both mentors and mentees were medical students. Of these, most (15) were longitudinal programs, aimed at first year students or the pre-clinical to clinical transition. All programs reported academic (development of clinical confidence, skills in patient care, procedural skills, medical knowledge, interviewing and examination skills) and non-academic (confidence, social support, peer relationships and communication skills) benefits for both mentors and mentees. Further, many studies identified elements for success such as orientation and training for mentors and challenges such as avoidance overload of mentors and logistics. Section title: Discussion Educational score: 2.0999577045440674 Domain: other Document type: Review Language: en These findings are consistent with those of previous reviews [ 15 , 21 – 23 ], and affirm the role of ‘social congruence’. The included studies found that mentees highlighted the ability for mentors to empathise with mentees as an important element of effective peer mentoring . They also felt that social congruence allowed the establishment of a ‘safe space’ in a peer mentoring group . Although not the primary aim of peer mentoring, it was notable that mentees developed academic and professional skills likely as a result of role modelling from mentors . Section title: Discussion Educational score: 4.055065155029297 Domain: biomedical Document type: Review Language: en This review identified several elements that were important for a successful program. Firstly, a number of included studies highlighted the importance of matching mentors and mentees based on additional shared characteristics such as clinical experiences or demographics . These shared traits could facilitate the initiation of a mentoring relationship. A recent systematic review suggested that sharing of specific socio-demographics may be particularly important for more vulnerable mentees such as underrepresented groups . Secondly, an important element of program success was the orientation and training provided to mentors which clarified their role and the objectives of the program and this was reinforced as a recommendation by programs where this was lacking . Orientation was also important for mentees . Interestingly, two studies reported that training was not necessary, given students had spent time as a mentee prior to being a mentor . However, these exceptions would require further evaluation. A related consideration was the balance between training and overload of mentors as ‘extensive, uncompensated training (could) discourage volunteer mentors’ . As part of the training, consideration could be given to ensuring mentors understand the role of greater support systems, especially since perceived independence of the program from the medical school was seen as a bonus for mentees and mentors . This would mitigate concerns which have been raised where the independence of peer mentoring programs from faculty staff could potentially result in the loss of other, formalised support systems . Bias awareness training on diversity and inclusion could also be considered for a more inclusive environment . Section title: Discussion Educational score: 1.7360846996307373 Domain: other Document type: Other Language: en Other elements to consider for program success raised by a small number of included studies included (1) the possibility of protected time allocation for peer mentoring ; students nevertheless reported their relatively flexible schedules made meeting peer mentors far easier than faculty mentors ; (2) face-to-face meetings where possible ; (3) small group sizes given large social media platforms did not allow for the more complex elements of peer mentoring ; and (4) remuneration especially for disadvantaged groups which could allow for improved equity. Interestingly, common resource limitations such as cost and sustainability were not raised by the studies as elements for success. Section title: Discussion Educational score: 3.9260101318359375 Domain: biomedical Document type: Study Language: en Limitations of this study included the challenges of developing a search strategy in the absence of ‘mentoring’ as a MeSH term and the heterogeneous use of terminology (such as ‘buddy’) to describe mentoring programs. Several keywords were used in the search strategy for comprehensiveness; however, it is possible these did not capture all available studies. It is also possible that peer mentoring programs were missed in the exclusion of peer-assisted learning studies; however, there was a low threshold for full text reviews to be conducted when uncertain. Further, restrictions to English language only and to the listed databases meant that it is possible that studies in other languages and/or other databases could have been missed. All included studies had significant methodological weaknesses, such as lack of randomisation, blinding and control groups. There was also heterogeneity of the study designs and outcome measures which made comparisons challenging and all included studies reported at least one positive outcome, raising the possibility of publication bias although a grey literature search was conducted. Section title: Discussion Educational score: 3.930539846420288 Domain: biomedical Document type: Review Language: en This scoping review has highlighted significant gaps in the current literature, and hence, further research should consider the following: Using robust methodology with validated outcome measures and performing statistical analysis for significant differences. Comparing different types of interventions (given the ethical difficulties of having controls). Including delayed outcome measures to determine longitudinal outcomes. Section title: Discussion Educational score: 2.0685641765594482 Domain: other Document type: Other Language: en Based on the findings of this review, educators should consider the following recommendations when designing peer mentoring programs: Clearly specified aims, outcomes and roles for mentors and mentees. Training and orientation for mentors. Longitudinal programs provide support for students as their experiences change throughout their degree. Multi-year programs enable a deeper development of relationships which may increase participation and retention. Shorter, focused programs specifically for high-stress points, such as transition points or examination times. Section title: Conclusion Educational score: 3.3895881175994873 Domain: biomedical Document type: Review Language: en Our review found that peer mentoring programs where medical students are mentored by medical students provide benefits, including improving psychosocial wellbeing and academic development. Challenges in development and implementations included workload concerns for mentors, logistical concerns for face-to-face programs and financial limitations. Section title: Conclusion Educational score: 2.0169599056243896 Domain: biomedical Document type: Other Language: en Key elements which optimise delivery of these programs include orientation and training for mentors and a clear outline of roles for both. Medical educators could consider the implementation of these programs as part of their medical school curricula. | Other | other | en | 0.999996 |
PMC11699105 | Section title: Introduction Educational score: 3.968174457550049 Domain: biomedical Document type: Study Language: en Successful biofuel feedstock crops necessitate a high germination rate, emergence, and stand establishment . The efficient establishment of new feedstock species in a novel environment relies on its capacity to emerge and establish uniformly and rapidly , as well as to yield under diverse environmental conditions. Climate change is progressing rapidly, resulting in variations in abiotic stresses, including frequent flooding, extended drought periods, and increased occurrences of both low and high-temperature episodes . Hence, identifying adaptable genotypes and appropriate management practices is essential for optimizing yield . The establishment of a crop stand is influenced by internal factors such as seed viability, maturation, genotype, and dormancy, as well as external factors, including water, light, temperature, and oxygen . Section title: Introduction Educational score: 3.358428478240967 Domain: biomedical Document type: Other Language: en Brassica carinata A. Braun, known as Ethiopian mustard or carinata, is an oilseed crop recognized for its potential in biofuel production , attributed to its high erucic acid content . Carinata, due to its area of origin, exhibits superior adaptation to semi-arid regions , demonstrating enhanced tolerance to moisture stress, elevated temperatures , seed shattering , drought , and diseases . Carinata is the product of interspecific hybridization between black mustard ( B. nigra L.) and wild cabbage ( B. oleraceae L.), both of which are genetically related to Brassica species . Carinata is an amphidiploid demonstrating high survival and adaptability [ , , ] yet exhibiting low cold tolerance . Genetic characteristics among genotypes may influence the adaptability range of a genotype to specific regions . The Southeast Partnership for Advanced Renewables from Carinata (SPARC), led by the University of Florida, FL, USA, is engaged in efforts to eliminate physical, environmental, social, and economic barriers to its adoption and output while also addressing risks across the supply chain . Section title: Introduction Educational score: 3.459818124771118 Domain: biomedical Document type: Study Language: en Temperature significantly influences seed germination, emergence, growth, and development . It affects both the percentage of seed germination and the germination rate in most crop species [ , , ]. Elevated temperatures can lead to restricted availability of photosynthetic assimilates during seed development [ , ], potentially causing physiological damage and resulting in either lower or no germination . Successful establishment of commercial crops requires knowledge of optimum growing conditions and effective establishment techniques . In addition, the environmental conditions during growth and developmental stages influence the yield of crops, including Brassica species . Section title: Introduction Educational score: 3.9475767612457275 Domain: biomedical Document type: Study Language: en The process of seed germination typically occurs within a defined temperature range known as cardinal temperature . This range includes minimum (T min ), optimum (T opt ), and maximum (T max ) temperatures, which are essential for constructing models that predict seed germination and developmental processes . Various mathematical models have established the correlation between germination rate and temperature . For instance, quadratic, linear, and nonlinear regression models were employed to quantify the response of seed germination to temperature stress [ , , , ]. However, the estimation of germination curves based on nonlinear regression leads to inappropriate standard errors, instead a log-logistic function will better fit the time-to-event data . To date, no attempts have been made to document the seed germination and its cardinal temperatures in carinata species. Section title: Introduction Educational score: 4.041955947875977 Domain: biomedical Document type: Study Language: en The assessment of temperature adaptability in genotypes has primarily relied on screening nurseries, field performance, and visual evaluations focused on survival . Interactions that are difficult to control complicate the separation of water, heat, and biotic factors from germination potential. Consequently, an efficient, reliable, and straightforward approach is necessary to evaluate numerous genotypes for thermotolerance in controlled environments . Numerous studies have employed parameters such as seed germination rate and potential to assess the tolerance of crop genotypes to abiotic stresses across various species . This evaluation encompasses both vegetative and reproductive, as well as physiological and biochemical factors during the germination stage . Multiple studies made use of the cumulative temperature response index (CTRI) [ 40 , , , ] to categorize different crop genotypes into tolerance groups for temperature stresses. Section title: Introduction Educational score: 3.591017961502075 Domain: biomedical Document type: Study Language: en The study aimed to (a) quantify the impact of temperature on carinata maximum seed germination (MSG) and seed germination rate (SGR), (b) identify the cardinal temperatures for MSG and SGR, and (c) screen carinata genotypes for temperature tolerance. Section title: Seed material Educational score: 4.174469470977783 Domain: biomedical Document type: Study Language: en The study evaluated eleven advanced carinata genotypes, including three breed types: inbred, double haploid, and hybrid, alongside one commercial check entry, Avanza 641( Table 1 ). The seeds were collected in Florida (8 genotypes) and Canada (4 genotypes) from Agrisoma Biosciences Inc., Canada (now Nuseed). Prior to the experiment, the seeds were treated with Helix Vibrance, consisting of fungicides (difenoconazole, metalaxyl-M, fludioxonil, and sedaxane) and insecticides (difenoconazole and metalaxyl thiamethoxam). All the seeds were stored in a refrigerator at 4 °C for equal time to maintain optimum quality until time for further use. The seeds with uniform size, shape, and maturity were randomly selected from a single seed lot for each genotype to study the germination behavior of B. carinata genotypes across a range of temperatures. The seed weight (SWGT) of individual genotypes was recorded before starting the temperature treatments and was expressed in mg seed −1 . Table 1 Type and origin of Brassica carinata genotypes sourced from Agrisoma Biosciences, 2019 (now Nuseed). Table 1 Genotype Type a Justification AX17001 Inbred Selection from SE16-17 AYT (Avanza family selection) Florida AX17002 Inbred Selection from SE16-17 AYT (Avanza family selection) Florida AX17004 Inbred High shatter tolerance family, good potential in a winter environment AX17005 Inbred High shatter tolerance family, good potential in a winter environment AX17006 Inbred High shatter tolerance family, good potential in a winter environment AX17007 Double haploid Among the highest Sclerotinia incidence, Jay and Quincy, FL AX17008 Double haploid Selection from SE16-17 PYTB Florida AX17009 Double haploid Selection from SE16-17 PYTA Florida AX17010 Double haploid Selection from SE16-17 PYTB Florida AX17014 Hybrid Top 2016-17 Quincy test hybrid Florida AX17015 Hybrid Promising test hybrid from 2017, frost-tolerant female Avanza 641 Check Commercial check a Genotypes are classified into three types (I = inbred, DH = double haploid, and H = hybrid). Seed trials (SE - Southeast, AYT - advanced yield trial, PYT - preliminary yield trial). Section title: Seed germination and temperature treatments Educational score: 4.170876502990723 Domain: biomedical Document type: Study Language: en The germination of carinata seeds was evaluated under various temperatures from May to September 2019. The study was conducted in vitro at the Environmental Plant Physiology Laboratory, Mississippi State University, Mississippi State, MS, USA. The study was performed following the guidelines established by the Association of Official Seed Analysts without humidity control. The experiment followed a completely randomized, two-factorial design with genotypes and temperatures serving as the primary source of variation. A total of 12 carinata genotypes were subjected to eight temperature treatments, with each treatment replicated four times using 100 seeds per replication. The eight levels of germination temperatures ranged from 8 to 37 °C in 5 °C increments; however, the actual temperatures recorded during the experiment were 8.2, 12.73, 15.65, 19.93, 23.8, 29.28, 34.22, and 36.96 °C. Each experimental unit consisted of 100 counted and weighed seeds, which were uniformly arranged on sterilized plastic trays measuring 31 cm in length × 24 cm in width. The trays were lined with double layers of sterilized paper towels (Scott Shop towels, Kimberly-Clark, Irving, TX, USA). Paper towels were wetted with sterile distilled water, and trays were covered to reduce moisture loss and arranged vertically in a germination chamber (Fisher Scientific, Inc., Suwanee, GA, USA), maintained at designated treatment temperatures. The chamber's internal temperature was measured using data loggers (WatchDog Model 100, Spectrum Technologies, Inc., Aurora, IL, USA) positioned uniformly on the top, middle, and bottom shelves. After incubation, the trays were examined at 2-h intervals to record seed germination. Seeds were counted as germinated when the radicle reached a length of at least 50 % of the seed's total length. The germinated seeds were counted, recorded, and subsequently discarded. The seed germination experiment was concluded after observing no germination for five consecutive days or eight days post-incubation. Section title: Germination-time course curve fitting procedure Educational score: 3.7604804039001465 Domain: biomedical Document type: Study Language: en Temperature and seed germination time course data were analyzed using a 4-parameter Weibull function (Eq. (1) ) in Sigma Plot 13 (Systat Software, Inc., San Jose, CA, USA). (Eq.1) Y = a ∗ [ 1 − e − [ x − x 0 + b ln 2 1 c b ] c ] Section title: Germination-time course curve fitting procedure Educational score: 3.95334529876709 Domain: biomedical Document type: Study Language: en This function estimates the total seed germination percentage (Y) using the maximum cumulative seed germination percentage (a) at a specific time (x), the shape (c) and steepness (b) of the curve, and the time required to achieve 50 % of the MSG (x 0 ). The reciprocal of the time to 50 % of the cumulative MSG (x 0 ) was used as the rate of development or the seed germination rate (SGR). Section title: Determination of cardinal temperatures Educational score: 4.1678361892700195 Domain: biomedical Document type: Study Language: en The responses of MSG and SGR to temperature treatments were analyzed using best-fitted linear and nonlinear regression models to ascertain the cardinal temperatures for all tested genotypes. The optimal curve fitting model was determined based on the highest coefficient of determination ( r 2 ) value. A quadratic model effectively described the relationship between MSG and SGR response to temperature, evidenced by a mean r 2 of 0.85. In contrast, the modified bilinear model test resulted in an overestimation of T max and an underestimation of T min for SGR. The quadratic model was employed to estimate MSG (%; Eq. (2) ) and SGR (d −1 ; Eq. (3) ). The cardinal temperatures (T min , T opt , and T max ) were determined using Equations (Eq. 4) , (Eq. 5) , (Eq. 6) ). The temperature adaptability range (TAR) for each genotype was determined using Equation (7) . (Eq. 2) M S G = a + b T + c T 2 (Eq. 3) S G R = a + b T − c T 2 (Eq. 4) T o p t = − b ( 2 c ) (Eq. 5) T min = − b + b 2 − 4 a c 2 c (Eq. 6) T max = − b − b 2 − 4 a c 2 c Where: Section title: Determination of cardinal temperatures Educational score: 1.9021046161651611 Domain: biomedical Document type: Other Language: en T min , T opt , and T max are the minimum, optimum, and maximum cardinal temperatures for seed germination. Section title: Determination of cardinal temperatures Educational score: 2.149981737136841 Domain: biomedical Document type: Study Language: en a , b , and c are genotype-specific regression constants. Section title: Determination of cardinal temperatures Educational score: 2.8004679679870605 Domain: biomedical Document type: Study Language: en T is the treatment temperature at which MSG was determined. (Eq. 7) T A R = T max − T min Section title: Cumulative high-temperature response index (CHTRI) Educational score: 4.083715915679932 Domain: biomedical Document type: Study Language: en The high-temperature response indices were computed based on the standardized vigor index . The individual temperature response index (ITRI) for each of the six parameters (P), specifically, MSG, SGR, T opt , and T max of MSG and SGR, was assessed for high-temperature tolerance across each genotype. The computation involved dividing the value for each genotype by the maximum value observed across all studied genotypes. The cumulative high-temperature response index (CHTRI) was determined by summing the six ITRI derived from MSG, SGR, and T opt , and T max of MSG and SGR. Section title: Cumulative low-temperature response index (CLTRI) Educational score: 4.06920051574707 Domain: biomedical Document type: Study Language: en The ITRI for low-temperature tolerance was derived from MSG, SGR, T min and T opt temperatures for MSG and SGR, which are analogous to the determination of CHTRI. The ITRI from T min from MSG and SGR was calculated by dividing the minimum value by the values for each genotype observed across all the genotypes. The cumulative low-temperature response index(CLTRI) was determined by summing all six ITRI values. Section title: Data analyses Educational score: 4.067336082458496 Domain: biomedical Document type: Study Language: en Regression procedures in Sigma Plot 13 were used to estimate MSG with time and to fit Weibull and polynomial functions for cumulative time series and germination rate data. The MSG, SGR, and SWGT data were analyzed using two-way factorial ANOVA and the ‘doebioresearch’ package in R studio. The data for T min, T opt , T max , and TAR were analyzed using the PROC GLM (one-way ANOVA) procedure in SAS to determine the effect of the germination temperature treatments on MSG and SGR together with their respective cardinal temperatures. Means were separated using Fisher's protected least significant difference (LSD) at p < 0.05. Temperature and time to germination were considered as independent variables, while germination factors (MSG and SGR) were dependent variables. Section title: Principal component analysis (PCA) Educational score: 3.910574436187744 Domain: biomedical Document type: Study Language: en The ITRI for each of the six parameters, i.e ., MSG, SGR, and T min , T opt , and T max of MSG and SGR of individual genotypes from high- and low-temperature tolerance response index were used to obtain the principal components (Dimension; Dim.) for high- and low-temperature response. The factor vectors were identified using the loadings of each trait at individual principal components. Depending on the genotype loading values, a scatter plot was created for high- and low-temperature tolerance. The analysis was performed in R studio using ‘factoextra’ package . Section title: Bubble plot Educational score: 2.509232997894287 Domain: biomedical Document type: Study Language: en We utilized the computed CHTRI and CLTRI values to generate a bubble plot aimed at identifying the most high and low-temperature tolerant individual among the carinata genotypes under study. The ‘ggplot2’ package in R studio created the bubble plot. Section title: Results and discussion Educational score: 3.4677236080169678 Domain: biomedical Document type: Study Language: en Temperature is a critical factor in the regulation of crop growth and development. This study is the first attempt to address the impact of temperature on seed germination traits across multiple B. carinata genotypes. This functional algorithm between seed germination and temperature derived in the study will be instrumental in developing models for carinata in field applications. The thermotolerance capacity observed among carinata genotypes will assist breeders in developing new germplasm suitable for both low and elevated temperatures during seed germination. Section title: Germination time course Educational score: 4.211190223693848 Domain: biomedical Document type: Study Language: en The impact of temperature on cumulative MSG and SGR, as well as variations in germination time, was examined across all carinata genotypes . The impact on four different breed types, viz., cultivar , inbred , double haploid , and hybrid , are shown in Fig. 1 . A four-parameter Weibull function exhibited a good fit across all tested carinata genotypes ( Table 2 ; mean r 2 = 0.86). All genotypes exhibited variability in their response to various temperature treatments. At the maximum temperature tested (36.96 °C), fewer than 10 % of germination was recorded for over 50 % of the genotypes. The cumulative MSG for all genotypes declined below 23.80 °C. The MSG was highest at 23.80 °C and lowest at 36.96 °C . Dawadi et al. indicated that the carinata seed MSG exceeded 80 % at a constant temperature of 25 °C, taking approximately 60 h to achieve this MSG, with germination onset occurring after 12 h. The duration required for the initiation of germination (≤24 h) exhibited variability among carinata genotypes and treatments in this study . Seed emergence occurred most rapidly at temperatures of 23.80 °C and 29.28 °C, within 0.5 days. The two lower temperatures (8.20 and 12.73 °C) and the highest temperatures (36.96 °C) resulted in a delay of seed emergence exceeding one day. Fig. 1 Seed germination time courses of four Brassica carinata genotypes representing various groups, (a) cultivar – Avanza 641, (b) Inbred – AX17005, (c) Double haploid – AX17008, and (d) Hybrid – AX17014, germinated at eight temperatures (8.2, 12.73, 15.65, 19.93, 23.8, 29.28, 34.22, and 36.96 °C); the symbols indicate the observed cumulative germination data, and the lines indicate the germination time courses fitted using a 4-parameter Weibull function. Data are means of four replications. Fig. 1 Table 2 Quadratic equation constants (a, b, and c), coefficients of determination ( r 2 ), cardinal temperatures (T min , T opt , and T max ), maximum seed germination (MSG), temperature adaptability range (TAR) for MSG, and mean individual seed weight (SWGT) of 12 Brassica carinata genotypes evaluated under eight temperature treatments. Table 2 Genotype Equation constants r 2 Cardinal temperatures (°C) TAR (°C) d SWGT (mg seed −1 ) c MSG (%) c a b c T min d T opt d T max d AX17001 96.97 bc −39.76 12.96 −0.3073 0.85 3.33 bc 21.09 c 38.86 b 35.53 cd 0.426 e AX17002 59.01 f −66.19 11.08 −0.2452 0.77 7.08 a 22.60 b 38.11 b 31.03 d 0.372 f AX17004 100.0 a −82.47 14.34 −0.2770 0.93 6.59 ab 25.89 a 45.18 a 38.59 b 0.343 g AX17005 96.48 b 14.88 8.39 −0.2159 0.76 −1.70 d 19.44 de 40.58 b 42.28 b 0.506 ab AX17006 73.12 e 13.32 5.38 −0.1208 0.84 −2.35 cd 22.25 b 46.85 a 49.21 ab 0.378 f AX17007 98.20 b 16.61 9.03 −0.2498 0.95 −1.75 d 18.07 f 37.90 b 39.65 c 0.500 b AX17008 88.00 ed 8.56 8.43 −0.2237 0.92 −0.99 d 18.85 f 38.68 b 39.67 c 0.408 e AX17009 100.0 a 43.09 6.12 −0.1536 0.64 −6.11 e 19.92 d 45.94 a 52.05 a 0.514 a AX17010 93.00 c −14.53 10.58 −0.2601 0.82 −1.42 cd 20.33 d 39.24 b 37.82 c 0.384 ef AX17014 92.8 c 14.10 8.42 −0.2254 0.94 −1.60 d 18.69 ef 38.98 b 40.58 c 0.493 bc AX17015 96.37 bc 9.70 9.02 −0.2346 0.91 −1.05 d 19.22 d 39.49 b 40.54 c 0.470 d AVANZA641 77.71 e 10.04 7.27 −0.1952 0.93 −1.33 d 18.62 f 38.57 b 39.91 c 0.428 e Mean 89.30 ˗ ˗ ˗ 0.86 −0.14 20.41 40.70 40.57 0.4355 LSD 4.7 b ˗ ˗ ˗ ˗ 4.43 b 0.89 b 3.74 b 7.97 a 0.0203 b The letters near the values are the results of Fisher's protected least significant difference (LSD); values with different letters are significantly different (p < 0.05), and the same letters are not significantly different (p > 0.05). a Significant at the 0.05 probability level. b Significant at the 0.001 probability level. c Two-way ANOVA was performed, taking temperature and genotype as main factors. The effect of temperature, genotype, and interaction were significant at p < 0.001 for MSG and SWGT. d One-way ANOVA was performed, taking genotype as the main factor. Fig. 2 Temperature effects on maximum seed germination (MSG) of 12 Brassica carinata genotypes. (a) Genotypes, AX17001, AX17002, AX17004, AX17005, AX17006, and AX17007, (b) AX17008, AX17009, AX17010, AX17014, AX17015, and Avanza 641. The lines are fitted with quadratic equations. Data are means of four replications. The symbols observed the maximum seed germination percentage. Fig. 2 Section title: Germination time course Educational score: 2.349813222885132 Domain: biomedical Document type: Study Language: en Temperature significantly influences seed germination . The available data on the germination capacity and rate of carinata across various temperatures is limited. This study established a functional database for temperature and seed germination traits, as well as a thermotolerance classification for carinata genotypes. Section title: Maximum seed germination response to temperature Educational score: 4.126053810119629 Domain: biomedical Document type: Study Language: en A significant genotype × temperature interaction was observed on MSG (p < 0.001). The response of MSG to temperature was modeled using a quadratic regression, yielding a mean r 2 of 0.86. The response of carinata genotypes to temperature for MSG exhibited variability, with values ranging from 59.01 % to 100 % , resulting in a mean of 89.30 % across genotypes . The variations in response patterns contributed to the interaction effect. Section title: Maximum seed germination response to temperature Educational score: 4.171152591705322 Domain: biomedical Document type: Study Language: en Parameters derived from the germination-time course data were used to calculate T min , T opt , and T max for MSG. The cardinal temperatures varied significantly among ( p < 0.001; Table 2 ). The estimated T min values varied from −6.11 to 7.08 °C , yielding a mean of −0.14 °C. The mean T opt was 20.41 °C. Genotype AX17004 exhibited the highest T opt value at 25.89 °C, whereas genotype AX17007 recorded the lowest at 18.07 °C. The mean T max was 40.70 °C, with genotype AX17007 exhibiting the minimum T max value of 37.90 °C, whereas genotype AX17006 and AX17009 displayed the maximum values of 46.85 and 45.94 °C which are statistically non-significant ( Table 2 ). The TAR (T max -T min ) indicated genotype-specific germination capacities across different temperature conditions. Carinata genotypes exhibited variations in TAR (p < 0.05; Table 2 ), with a mean value of 40.57 °C, ranging from 31.03 °C to 52.05 °C . Section title: Maximum seed germination response to temperature Educational score: 4.17658805847168 Domain: biomedical Document type: Study Language: en Research on the germination response to temperature in various plant species indicates that while there is variability in seed germination, utilizing this parameter for genotype screening may be impractical due to the influence of multiple factors on MSG . These factors include seed traits , the duration of storage between ripening and planting , and the environmental conditions during maternal seed production . The variation in TAR among genotypes suggests that differing genetic traits influence their adaptation and performance under varying temperatures . The optimal temperatures for MSG differed among genotypes, exhibiting a range of responses with varying MSG levels across all genotypes. Genotype AX17002 exhibited the lowest percentage of MSG at 59.01 %. The cardinal temperatures for canola, as indicated by a comparable model, show a T min range of 0 to 3 °C, T opt of 29 to 33 °C, and T max of 35 °C . Our study indicated that the values for T min and T opt ranges were lower, whereas T max was higher. In Canada and the northern tier states of the United States, carinata and canola are grown in similar areas. Establishing the cardinal temperatures for carinata genotypes aids plant breeders and producers by enhancing the understanding of crop species and their necessary conditions for establishment. Section title: Seed germination rate response to temperature Educational score: 4.248653888702393 Domain: biomedical Document type: Study Language: en A quadratic regression model effectively characterized the relationship between SGR and temperature (mean r 2 = 0.85; Table 3 ). A significant genotype × temperature interaction was observed on SGR (p < 0.001). Among genotypes, SGR increased with a temperature rise from 8.2 to 23.8 °C, followed by a gradual decline as the temperature reached 36.69 °C. The estimated SGR was highest at 0.98 d −1 at 19.93 °C and lowest at 0 d −1 at 36.96 °C . The findings align with similar results obtained from eight rapeseed cultivars assessed within a temperature range of 3 to 23 °C . Table 3 Quadratic equation constants (a, b, and c), coefficients of determination ( r 2 ), cardinal temperatures (T min , T op t, and T max ), seed germination rate (SGR), and temperature adaptability range (TAR) for SGR, of 12 Brassica carinata genotypes evaluated under eight temperature treatments. Table 3 Genotypes Equation constants Cardinal temperatures (°C) SGR (d −1 ) c a b c r 2 T min d T opt d T max d TAR d AX17001 0.63 f −0.3342 0.0799 −0.0017 0.88 4.63 c 22.04 c 43.45 ab 38.82 bc AX17002 0.52 g −0.339 0.0779 −0.0018 0.75 4.90 c 21.98 d 39.06 c 34.17 c AX17004 0.97 b −0.8306 0.1305 −0.0024 0.85 7.34 a 27.65 a 47.96 a 40.62 a AX17005 0.97 b −0.7459 0.1355 −0.0027 0.86 6.28 a 25.38 b 44.49 ab 38.20 bc AX17006 0.71 e −0.2518 0.072 −0.0013 0.82 3.76 d 26.71 ab 49.65 a 45.89 a AX17007 0.76 d −0.6386 0.1261 −0.0028 0.85 5.83 abc 22.20 c 38.57 c 32.74 c AX17008 0.70 e −0.2767 0.0798 −0.0016 0.89 3.75 d 24.55 b 45.35 ab 41.60 a AX17009 0.99 b −0.7696 0.1417 −0.0029 0.89 6.21 a 24.82 b 43.42 b 37.22 bc AX17010 0.74 d −0.3717 0.0888 −0.0018 0.93 4.61 c 25.08 b 45.56 ab 40.95 ab AX17014 0.93 c −0.6156 0.1283 −0.0027 0.86 5.41 abc 24.11 b 42.81 b 37.41 bc AX17015 1.08 a −0.7178 0.1433 −0.0029 0.90 5.64 abc 25.14 b 44.64 ab 39.00 bc AVANZA 641 0.66 f −0.4614 0.0999 −0.0022 0.71 5.23 b 22.40 b 39.57 c 34.34 c Mean 0.81 ˗ ˗ ˗ 0.85 5.30 24.51 43.71 38.41 LSD 0.04 b ˗ ˗ ˗ ˗ 2.03 a 1.73 b 4.58 a 6.58 b The letters near the values are the results of Fisher's protected least significant difference (LSD); values with different letters are significantly different (p < 0.05), and the same letters are not significantly different (p > 0.05). a Significant at the 0.05 probability level. b Significant at the 0.001 probability level. c Two-way ANOVA was performed, taking temperature and genotype as main factors. The effect of temperature, genotype, and interaction were significant at p < 0.001 for SGR. d One-way ANOVA was performed, taking genotype as the main factor. Fig. 3 Temperature effects on seed germination rate (SGR) of 12 Brassica carinata genotypes. (a) Genotypes, AX17001, AX17002, AX17004, AX17005, AX17006, and AX17007, (b) AX17008, AX17009, AX17010, AX17014, AX17015, and Avanza 641. Data are means of four replications. The symbols are observed seed germination rates. Fig. 3 Section title: Seed germination rate response to temperature Educational score: 4.116711616516113 Domain: biomedical Document type: Study Language: en The cardinal temperatures for SGR varied significantly across the genotypes ( p < 0.05; Table 3 ). The T min ranged from 3.75 °C to 7.34 °C , with a average of 5.30 °C. The estimated mean of T opt was 24.51 °C, with a range from 21.98 °C to 27.65 °C . The two genotypes, AX17007 and AX17002, exhibited the lowest T max value of 38.57 °C and 39.06 °C, respectively. The highest T max was 49.65 , resulting in an estimated mean of 43.71 °C ( Table 3 ). Section title: Seed germination rate response to temperature Educational score: 4.171760559082031 Domain: biomedical Document type: Study Language: en The TAR for SGR varied between 32.74 °C and 45.89 °C with an average of 38.41 °C ( Table 3 ). Unlike reports on other crop species, the SGR for carinata varied across a range of temperatures, lacking a clearly defined optimum . The rate decreased linearly and rapidly with rising temperatures. Soltani et al. reported that in most plant species, the growth rate increases from minimum to optimum temperatures and declines between optimum and maximum temperatures, consistent with the quadratic model predictions and actual data for the carinata genotypes studied. In our study, the SGR cardinal temperatures exceeded those of MSG, consistent with findings on ornamental peppers and switchgrass . This aligns with the findings of Schimpf et al. , indicating that the MSG exhibits lower temperature sensitivity compared to SGR. Seed germination is a temperature-dependent process; however, variation in cardinal temperatures among genotypes exists due to intra-specific differences related to genetic diversity, area of origin, or adaptation of these entries. Comparable results were observed for switchgrass . Kiniry et al. proposed that cardinal temperatures may vary based on genotype and specific processes. Section title: Principal component analysis (PCA) for high-temperature tolerance Educational score: 4.166717529296875 Domain: biomedical Document type: Study Language: en The PCA is an efficient dimension reduction technique widely used in data analysis . It simplifies the data into a set of uncorrelated variables called principal components (Dim.) based on the original data points. The method has been extensively used in the screening and selection of varieties and hybrids in multiple crops . The PCA analysis of carinata genotypes using six parameters (MSG, SGR, T opt, and T max of both MSG and SGR) resulted in six dimensions (Dim) with a major contribution from Dim.1 (55.9 %) and Dim.2 (26.7 %) . The correlation between parameters and Dim.s suggests that T opt of SGR (r 2 = 0.90) is highly contributing for Dim.1, followed by T max for SGR (r 2 = 0.77), T max for MSG (r 2 = 0.65), and SGR (r 2 = 0.59) . On the other hand, Dim.2 was highly explained by MSG (r 2 = 0.59). The fourth, fifth, and sixth Dimensions were only slightly correlated with the tested parameters from the studied genotypes. Fig. 4 The principal component analysis of 12 carinata genotypes for high-temperature tolerance, (a) Scree plot of six principal components with their respective variance (%), (b) Correlations of principal components with the variables (MSG, SGR, and T opt, and T max of both MSG and SGR), and (c) The individual parameter loadings towards the principal components, Dim.1 and Dim.2. The red to green color indicates the least to highest loading values of parameters in each dimension, (d) Variables as factor vectors at first two principal components (Dim.1 and Dim.2), and (e) Scatter plot of 12 carinata genotypes on the Dim.1 and Dim.2 factor planes based on the factor scores. Fig. 4 Section title: Principal component analysis (PCA) for high-temperature tolerance Educational score: 3.496380090713501 Domain: biomedical Document type: Study Language: en Depending on the loadings on Dim.1 and Dim.2, the parameters were placed on the vector planes . The Dim.1 was negatively related to all the high-temperature tolerance parameters, featuring the first quadrant as a low-temperature tolerant plane. The MSG and SGR had positive loadings on Dim. 2, while the other parameters were negatively associated with Dim.2 . The T max for MSG and SGR was located in the third factor quadrant, indicating that the genotypes placed in this quadrant will be tolerant to high temperatures. In addition, the MSG and SGR were placed in the second quadrant, indicating this will accommodate genotypes with high-temperature tolerance. Meanwhile, the first and fourth quadrants harbor high-temperature sensitive genotypes . Section title: Principal component analysis (PCA) for high-temperature tolerance Educational score: 3.9814388751983643 Domain: biomedical Document type: Study Language: en Based on the loadings of the carinata genotypes, a scatter plot was created revealing their temperature tolerance levels . The genotype AX17004 was the most high-temperature tolerant one due to its high loading value in the third quadrant, followed by AX17006. In the second quadrant, genotype AX17009 had the highest loading, showing its high-temperature tolerance. The second also accommodates AX17005 and AX17015 genotypes, expressing their moderate high-temperature tolerance compared to other genotypes. However, AX17007 and AX17002 were located in the first and fourth quadrants with a high loading value, revealing their notable high-temperature sensitivity among all the studied genotypes. The Avanza 641 was also located in the fourth quadrant, expressing its high-temperature sensitivity along with other sensitive genotypes. Section title: Principal component analysis for low-temperature tolerance Educational score: 4.170088291168213 Domain: biomedical Document type: Study Language: en As with the high-temperature tolerance, the PCA was performed for low-temperature tolerance using six factors derived from the seed germination assay (MSG, SGR, T min, and T opt for both MSG and SGR), where each parameter varied in their input based on its relation to the maximum or minimum constant for that particular factor measured across all the genotypes. The PCA analysis generated six principal components (Dim.s) to explain 100 % variance among the genotypes tested. The first two components collectively accounted for 76.9 % of the total variance . The SGR was highly correlated with Dim.1 (r 2 = 0.90), followed by MSG (r 2 = 0.71) . While Dim.2 was highly correlated with T opt for MSG (r 2 = 0.92). All the parameters were negatively associated with Dim.1 . In contrast, Dim.2 was positively associated with MSG, SGR, and T opt for MSG . This contributed to the separation of the parameters in the four-factor quadrants . The Tmin for MSG and SGR was located in the second and third quadrant, respectively. Thus, genotypes in this quadrant will have low-temperature tolerance. Fig. 5 The principal component analysis of 12 carinata genotypes for low-temperature tolerance, (a) Scree plot of six principal components with their respective variance (%), (b) Correlations of principal components with the variables (MSG, SGR, and T opt, and T min of both MSG and SGR), and (c) The individual parameter loadings towards the principal components, Dim.1 and Dim.2. The red to green color indicates the least to highest loading values of parameters in each dimensions, (d) Variables as factor vectors at first two principal components (Dim.1 and Dim.2), and (e) Scatter plot of 12 carinata genotypes on the Dim.1 and Dim.2 factor planes based on the factor scores. Fig. 5 Section title: Principal component analysis for low-temperature tolerance Educational score: 4.141727924346924 Domain: biomedical Document type: Study Language: en The first and fourth quadrants accommodated genotypes such as Avanza 641 and AX17002 with low-temperature sensitivity. From the scatter plot using Dim.1 and Dim.2 components, the genotype AX17009 was observed to have a better low-temperature tolerance capacity, followed by AX17005 and AX17015. However, the genotypes harboring in the third quadrant exhibited a profile of being moderately low-temperature tolerant. A crucial goal for most plant breeding programs is to identify genotypes with essential traits that make them resilient to extreme thermal conditions , as well as to develop new genotypes with high field stress tolerance that can thrive under variable weather conditions . Several studies have used identical parameters to screen crops for temperature tolerance . Evaluating a crop genotype's thermal adaptability range is typically limited to visual field observation, field performance, and nursery screening. In these conditions, separating different abiotic and biotic stress factors is challenging. Hence, there is an urgent need for an environment where these stress factors are controlled. Setimela et al. suggested that evaluating the thermal adaptability range has paved the way for developing faster, more reliable, and low-cost methods to screen a large batch of plant materials for thermotolerance characteristics. In our study, genotype AX17009 was grouped as the most low-temperature tolerant. Also, genotypes AX17005, AX17014, and AX17015 appear to have good germination at the low-temperature treatment. The genotypes AX17002 and Avanza 641 were categorized as low-temperature sensitive. Data concerning thermotolerance screening for carinata genotypes and intraspecific variation in the establishment under different regions and thermal conditions are limited in the literature; however, there is a need for further testing. Section title: Cumulative high- and low-temperature tolerance response index Educational score: 4.127317428588867 Domain: biomedical Document type: Study Language: en The cumulative indices for high- and low-temperature tolerance responses were calculated to assess the overall reaction of 12 genotypes based on factors obtained from the germination assay. The CHTRI identified genotypes that are both high-temperature tolerant and sensitive. The genotype AX17004, with a CHTRI value of 5.82, demonstrated significant high-temperature tolerance relative to other genotypes . The genotypes AX17009 (5.43), AX17015 (5.32), and AX17005 (5.26) exhibited moderate tolerance to high temperatures. Conversely, AX17002 was recognized as a sensitive genotype, exhibiting a CHTRI value of 4.31. In contrast, AX17009 is identified as a low-temperature tolerant genotype, exhibiting a CLTRI value of 6.23. AX17005 achieved this with a value of 5.45, AX17015 at 5.23, and AX17007 at 4.99. The lowest CLTRI values were observed in AX17002 (2.86) and AX 17001 (3.88), indicating their sensitivity to low temperatures relative to the other carinata genotypes examined. The PCA analysis and bubble plot results complement each other, thereby reinforcing the reliability of the identified genotypes for high- and low-temperature tolerance. Fig. 6 Bubble plot of carinata genotypes for cumulative high-temperature tolerance response index (CHTRI) and cumulative low-temperature tolerance response index (CLTRI). Fig. 6 Section title: Parameter relationships Educational score: 3.899815320968628 Domain: biomedical Document type: Study Language: en A weak positive linear relationship was identified ( r 2 = 0.43) between the cumulative low-temperature response index (CLTRI) and the cumulative high-temperature response index (CHTRI) for 12 evaluated carinata genotypes evaluated . This relationship suggests that low- and high-temperature tolerance responses among these genotypes are distinct traits. Consequently, identifying genotypes exhibiting both low- and high-temperature tolerance is challenging. Thus, when developing tolerant genotypes, selection for low and high-temperature tolerance must be conducted separately. Fig. 7 The relationship between cumulative low- and high-temperature response index (CLTRI; CHTRI) of 12 Brassica carinata genotypes. Fig. 7 Section title: Parameter relationships Educational score: 4.162291526794434 Domain: biomedical Document type: Study Language: en A weak linear relationship exists between MSG T opt and T max , whereas a poor inverse relationship is observed between MSG T min and T max . As the minimum temperature for carinata genotypes increased, the optimal temperature also increased . Furthermore, SGR T max exhibited an increase corresponding to the rise in T opt . A weak inverse relationship was observed between SGR T min and T max , as well as a weak linear relationship between T min and T opt (r 2 = 0.043) . The study revealed that as the optimum temperature increased, the maximum temperature varied across genotypes but showed a weak correlation with T opt , suggesting that each genotype exhibited distinct T max values necessary for achieving MSG. There was a weak correlation between T min and T opt . As the minimum temperature for MSG increased, the optimum temperature also rose. The optimal temperature for SGR exhibited a linear increase with maximum temperature; however, T min , T max , and T opt were more specific to genotypes for SGR, as indicated by the observed weak relationships. Fig. 8 Relationship between the cardinal temperatures for maximum seed germination (MSG) of 12 Brassica carinata genotypes, the relationship between (a) minimum (T min ) and optimum or (T opt ) and maximum ( Tmax ) temperatures, (b) optimum (T opt ) and maximum (T max ) temperatures, and the relationship between (c) seed germination rate (SGR) and minimum (T min ) and optimum (T opt ) and maximum (T max ) temperatures, and (d) seed germination rate optimum (T opt ) and maximum ( Tmax ) temperatures of 12 Brassica carinata genotypes. Fig. 8 Section title: Parameter relationships Educational score: 3.5946438312530518 Domain: biomedical Document type: Study Language: en Research indicates that seed weight was not utilized as a criterion for classifying crop species into thermotolerance groups, owing to variations in origin and the influence of the parental environment . Individual seed weight varied among genotypes (p < 0.001; Table 2 ) and exhibited a weak correlation with MSG and SGR , suggesting that seed weight did not influence either MSG or SGR. A weak positive linear relationship was identified between MSG and seed weight as well as between SGR and seed weight . Fig. 9 The relationship between maximum seed germination (MSG), seed germination rate (SGR), and seed weight of 12 Brassica carinata genotypes. Fig. 9 Section title: Parameter relationships Educational score: 4.171442031860352 Domain: biomedical Document type: Study Language: en This study assessed the impact of temperature on the MSG capacity and SGR of 12 advanced carinata genotypes through in vitro analysis. Genotype-specific cardinal temperatures and thermal accumulation rates were estimated using best-fit regression models. The mean minimum, optimum, and maximum temperatures of the MSG for carinata genotypes were −0.14, 20.41, and 40.70 °C, respectively. The mean minimum temperature for SGR was 5.30 °C, the mean optimum temperature was 24.51 °C, and the mean maximum temperature was 43.71 °C. The average TAR for the genotypes was 40.57 °C for MSG and 38.41 °C for SGR. There was a variability among the genotypes concerning MSG, SGR, TAR, and cardinal temperature. Carinata genotypes were categorized into distinct groups based on their seed germination vitality traits, specifically regarding low- and high-temperature tolerance using principal component analysis and temperature response indices. The genotypes AX17004 and AX17009 were identified as the most tolerant to high and low temperatures, respectively. The double haploid and hybrid carinata breeding groups exhibited stable thermotolerance during the seed germination stage. Section title: Parameter relationships Educational score: 3.6276888847351074 Domain: biomedical Document type: Study Language: en The inbred group exhibited a more extensive cluster in response to both minimum and maximum temperatures. The research highlighted the necessity of a distinct selection of genotypes exhibiting tolerance to low or high temperatures. The data collected in this study indicate that the identified cardinal temperatures will enhance the development and application of carinata crop models in field production systems. Additionally, identifying genotypes that are tolerant to low and high temperatures will aid in delineating cultivation regions. Future evaluations of these genotypes under field conditions are necessary to identify and quantify those that exhibit tolerance to both low and high temperatures. Section title: CRediT authorship contribution statement Educational score: 0.9379634261131287 Domain: other Document type: Other Language: en Leelawattie Persaud: Writing – review & editing, Writing – original draft, Visualization, Methodology, Formal analysis. Naflath Thenveettil: Writing – review & editing, Formal analysis. Ramdeo Seepaul: Writing – review & editing, Funding acquisition. Bisoondat Macoon: Writing – review & editing, Supervision, Project administration, Funding acquisition, Formal analysis. Krishna N. Reddy: Writing – review & editing. Kambham Raja Reddy: Writing – review & editing, Visualization, Supervision, Software, Resources, Project administration, Methodology, Investigation, Funding acquisition, Formal analysis, Data curation, Conceptualization. Section title: Data availability statement Educational score: 0.8571403622627258 Domain: other Document type: Other Language: fr Data will be made available on request. Section title: Declaration of competing interest Educational score: 1.0250425338745117 Domain: other Document type: Other Language: en The authors declare the following financial interests/personal relationships that may be considered potential competing interests: Kambham R Reddy reports that the National Institute of Food and Agriculture provided article publishing charges, equipment, or supplies, and travel. | Study | biomedical | en | 0.999998 |
PMC11699107 | Section title: Introduction Educational score: 4.102262496948242 Domain: biomedical Document type: Review Language: en Patient-centered care is becoming the most valued medical care approach worldwide. It focuses on patients’ preferences, needs, and values in medical procedures . It has been defined through a multidimensional concept, consisting of five dimensions: the biopsychosocial perspective, patient-as-person, sharing power and responsibility, therapeutic alliance, and doctor-as-person . This theoretical framework translates into a clinical practice in which the doctor, through his own communication and relational skills, is able to catch the patient’s issues, concerns, needs, beliefs, and meanings related to health and disease, in addition to symptoms and medical anamnesis. In this such way, it comes to be built a common ground of knowledge that allows for a concordance on disease etiology and treatment chances, and a sharing clinical decision-making, prevention, and health promotion . Patient-centered care is proven to contribute to positive medical outcomes by promoting treatment adherence , reducing the occurrence of complications linked to poor prognosis and adverse events , and enhancing self-management . Moreover, it aims to improve patients’ emotional wellbeing and satisfaction for care , and contributes to reduce healthcare costs through reductions in expenses related to diagnostic testing and specialist referrals . Section title: Introduction Educational score: 3.860100746154785 Domain: biomedical Document type: Review Language: en Therefore, promoting and sustaining patient-centered care attitudes in future doctors has become a gold standard in medical education. However, a recent systematic review found that healthcare students have low attitudes toward patient-centered care . As a result, evaluating the level of such attitudes among students is a pressing and foremost priority, followed by the development of educational interventions able to fill the gap. Among the instruments built to measure patient-centered care attitudes to date, the Patient-Practitioner Orientation Scale (PPOS) is one of the most specific . The PPOS is an 18-item instrument in Likert format developed to capture healthcare students and professionals’ attitudes toward patient-centeredness . Section title: Introduction Educational score: 4.194790363311768 Domain: biomedical Document type: Study Language: en The 18-item version of the PPOS is the result of multiple studies which lack some clarity as a whole. The initial PPOS version was developed using a pool of 35 potential items, drawn from an extensive search of the literature about patient-practitioner relationship, administered to a sample of undergraduate medical students. All the selected statements were written to refer to one of the two a priori postulated dimensions underlying the patient-centeredness construct, namely Sharing and Caring. The first reflects responders’ beliefs about sharing information and decision-making power with the patients. The seconds corresponds to the disposition to take care of them as “people,” respecting their expectations, feelings, and beliefs. The initial pool of items was progressively modelled eliminating one statement at a time based on item-total correlation value, calculated for each dimension separately, up to a 20-item scale . A second study has been performed based on a different pool of 61 potential items administered to a sample of undergraduate psychology students. By using procedures similar to the above, 33 items were retained and the exploratory factor analysis (EFA) confirmed the scale construct as conceptually composed by the dimensions of Sharing and Caring . Both the studies explored basic psychometric properties of the scale and claimed the tool was reliable based on good total internal consistency, with Cronbach’s alpha ranging from .80 to .90. In a third study performed on a mixed sample of physicians and patients, the PPOS was presented as an 18-item instrument, notwithstanding this further shortening was not documented in that nor in other studies available in the literature. In this latter study, the internal consistency observed was acceptable for the total scale and poor for the items pertaining to the Caring dimension. No other assessment of psychometric properties of the tool had been carried out . Section title: Introduction Educational score: 3.3558990955352783 Domain: biomedical Document type: Study Language: en Despite this questionable and poor process of scale modelling and validation, the 18-item version of the PPOS began to be used in the medical education literature. It has been translated into various languages and the validity and reliability of the different adaptations have been tested in multiple studies [ 15 – 21 ]. Some of these found the two-factor solution unstable and questioned the two-dimensional model . Further studies suggested three-factor and four-factor solutions . Section title: Introduction Educational score: 2.882678270339966 Domain: biomedical Document type: Other Language: en Data suggesting the weakness of the PPOS two-dimensional model seem to confirm the multidimensional definition of the doctors’ patient-centered attitude , accordingly with the theoretical model proposed for patient-centered communication (consisting of four domains: patient’s perspective, psychosocial context, shared understanding, and sharing power and responsibility) . Section title: Introduction Educational score: 4.127298831939697 Domain: biomedical Document type: Study Language: en In summary, patient-centeredness construct dimensionality, as measured by the PPOS, is far from clear and the distinction from other basic related constructs (e.g., empathy, attitude toward care) has not already been ascertained. This study aims to begin to fill this gap by investigating the PPOS psychometric properties, factor structure, and construct validity on a large sample of undergraduate medical students. In particular, this study aims to answer the following research questions: (Q1) Is the PPOS a psychometrically valid tool for assessing the patient-centeredness among first-year medical students? (Q2) Is the PPOS factor structure two-dimensional? (Q3) Is the construct measured by the PPOS significantly different between groups distinguished by gender, preferential interest, and setting toward medical practice? Section title: Study Design, Procedures, and Participants Educational score: 4.030893325805664 Domain: biomedical Document type: Study Language: en This cross-sectional study was conducted at the beginning of a lectures cycle on doctor-patient relationship and healthcare environment features. It targeted first-year students at the University of Turin Medical School during the initial half of the academic year between October and November. All the questionnaires used in the study (i.e., the Patient-Practitioner Orientation Scale, the Jefferson Scale of Empathy, the Frommelt Attitude Toward the Care Of the Dying Scale, and the Perceived Stress Scale) were administered two times during the first and the third lecture, with an interval ranged between 15 and 17 days. Students accessed online platform via tablets or computers in the classroom to complete the questionnaires. They were informed about purposes and methods of the study; participants voluntarily agreed to participate without any reward, and informed consent was obtained before they started filling out the questionnaire. Prior to questionnaires’ completion, students accessed the online platform through their university accounts. To maintain anonymity, they were required to enter a personal identification code. This procedure was implemented to ensure anonymity and facilitate questionnaire cross-matching. The study met the principles of the Declaration of Helsinki and obtained the ethical approval by the University of Turin Ethical Review Committee . Data gathering was repeated for three consecutive academic years with the same procedures in order to enlarge the sample size. Section title: Measures Educational score: 1.9810492992401123 Domain: biomedical Document type: Study Language: en At the beginning of the questionnaire, participants were asked to provide information about demographics and their interests and preferences toward medical profession (through the dichotomies “technical and interventional medical procedures” vs “humanistic and relational aspects of medical practice” and “caring for outpatients” vs “working in operating room or lab”). Section title: Patient-Practitioner Orientation Scale (PPOS) Educational score: 3.908276081085205 Domain: biomedical Document type: Study Language: en The PPOS is a self-report questionnaire consisting of 18 items scored on a 6-point Likert-type scale (from 1 = “strongly agree” to 6 = “strongly disagree”) assessing attitudes toward patient-centeredness of healthcare students, physicians, and patients through two dimensions (9 items each): Sharing and Caring . Items are written in physician-oriented style, except items 6, 13, and 17. Scores of the scale and subscales are obtained by summing the items and dividing them by their corresponding number, so as the scores range between 1 and 6. The higher the score, the higher the attitude toward patient-centeredness. The 18-item Italian version of the PPOS developed by Ardenghi and colleagues was used in this study . Section title: Jefferson Scale of Empathy (JSE) Educational score: 3.1142566204071045 Domain: biomedical Document type: Study Language: en The JSE is a self-report questionnaire consisting of 20 items on a 7-point Likert-type scale (from 1 = “strongly disagree” to 7 = “strongly agree”) assessing empathic attitude in clinical practice of healthcare students and professionals . The Italian translation provided by Jefferson Medical College, previously validated by the authors , was used in this study. JSE scores range from 0 to 140; the higher the score, the greater the empathic attitude. Section title: Frommelt Attitude Toward the Care Of the Dying (FATCOD) Scale Educational score: 3.124755382537842 Domain: biomedical Document type: Study Language: en The FATCOD scale is a self-report questionnaire consisting of 30 items on a 5-point Likert-type scale (from 1 = “totally disagree” to 7 = “totally agree”) assessing the attitude toward the care of dying patients . The Italian shortened version validated by the authors (FATCOD-9IT) was used in this study . FACTOD-9IT scores range from 9 to 45; the higher the score, the greater the aversion toward the care of the dying. Section title: Perceived Stress Scale (PSS) Educational score: 2.904017686843872 Domain: biomedical Document type: Study Language: en The Perceived Stress Scale (PSS) is a self-report questionnaire consisting of 10 items on a 5-point Likert-type scale (from 0 = “never” to 4 = “very often”) measuring perceived stress . The Italian version of the tool was used in this study . PSS scores range from 0 to 40; the higher the score, the greater the level of the perceived stress. Section title: Visual Analog Scale (VAS) of Psychological Wellbeing Educational score: 2.699568510055542 Domain: biomedical Document type: Other Language: en A VAS was used to assess psychological wellbeing. It consists of a horizontal line of 100 mm in length anchored by descriptors to each end (“negative wellbeing” at left, “positive wellbeing” at right). Responders have to indicate with a mark on the line the point that best represents their psychological state. Scores are determined by measuring in millimeters from the left end of the line to the marked point . Section title: Statistical Analyses Educational score: 4.206686019897461 Domain: biomedical Document type: Study Language: en Data were analyzed with SPSS software v. 25.0 for Mac (IBM). Floor and ceiling effect for each PPOS item was investigated through the inspection of frequency tables, with a percentage ≥ 15% of respondents having scored the lowest or the highest point on the Likert-type scale considered indicative. PPOS factor structure was investigated through exploratory factor analysis (EFA) using the principal axis factoring (PAF) estimation method with orthogonal rotation and Kaiser-Meier-Olkin (KMO) measure of sampling adequacy > 0.70 (middling value) considered acceptable. Factors were extracted using the Kaiser-Guttman criterion (eigenvalues ≥ 1) and through the inspection of Cattell’s scree plot and the percentage of variance explained by the eigenvalues in the first round. Two fixed factors were extracted in the second round to simplify the factor structure (i.e., each variable should have one factor that clearly loads on it and each factor should clearly load on at least three variables), and improve its interpretability and understanding. Internal consistency of the scale was investigated by calculating Cronbach’s alphas and item-total correlations. Test–retest reliability was investigated through the inspection of intraclass correlation coefficients (ICC), with values ≥ 0.70 considered satisfactory. Robustness of construct validity was ascertained through the investigation of convergent and divergent validity and by testing a set of research hypotheses. Convergent-discriminant validity was investigated by calculating bivariate correlations (considering Pearson’s correlation coefficient) between each item of the PPOS and JSE, FATCOD-9IT, and PSS scores. It was expected that scales supposed to be conceptually related with PPOS items (i.e., JSE and, to a lesser degree, FATCOD-9IT, which is supposed to be conceptually related only with the Caring and not with the Sharing dimension) would be moderately positively correlated (i.e., Pearson r > 0.30). Conversely, it was expected that PSS, which is postulated to have little in common with PPOS items, would not be significantly correlated. Research hypotheses on between-group differences on PPOS score were developed and tested by specifying one-way multivariate analysis of variance (MANOVA) models with Scheffé post hoc test to address unequal group sizes, Cohen’s standardized effect size partial η 2 , and α set at 0.01. It was postulated that students who were females and had declared themselves more interested in humanistic and relational aspects of medical practice and prone to outpatient practice would score higher on the PPOS than those who demonstrated more interest toward technical and interventional medical procedures (e.g., lab test, surgery). Section title: Participant Characteristics and Scores Educational score: 4.023804664611816 Domain: biomedical Document type: Study Language: en Participants in this study were 1543 first-year medical students at the beginning of their medical training. All the students approached in the classroom agreed to participate in the study (response rate = 100%), accounting for the 93.5% of the total cohorts resulting from the sum of the students enrolled in three academic years . Of the participants, 596 (38.6%) were males, 943 were females (61.1%), and 4 were non-binary (0.3%). The mean age was 19.7 ± 1.8. VAS for psychological wellbeing was 6.8 ± 2.0 (cm). Most of the participants stated they were more interested in technical and interventional medical procedures rather than in humanistic and relational aspects of medical practice ( n = 776, % = 50.3 vs n = 601, % = 39.0) and they felt more prone to visit and care for outpatients rather than work in operating room or lab ( n = 799, % = 51.8 vs n = 578, % = 37.5). A relevant number of participants ( n = 166, % = 10.8) expressed no choice with respect to interest or preference for their future medical practice. Section title: Participant Characteristics and Scores Educational score: 2.220238208770752 Domain: biomedical Document type: Study Language: en Participants scored 3.9 ± 0.5 on the PPOS, 106.5 ± 12.3 on the JSE, and 18.8 ± 6.3 on the PSS. Response rate for PPOS was 89.2%. Section title: Floor and Ceiling Effect Educational score: 4.188394069671631 Domain: biomedical Document type: Study Language: en In this study, floor and ceiling effects correspond to having answered to a PPOS item “1 = strongly agree” and “6 = strongly disagree,” respectively. Floor effect ranged from 21.3% (item 5) to 40.1% (item 18). Ceiling effect ranged from 17.9% (item 8) to 74.9% (item 6). Full details are given in Table 1 . Table 1 Floor/ceiling effect and factor structure of the Italian version of the Patient-Practitioner Orientation Scale (PPOS) PPOS item % of scores Factor loading Low High F1 F2 F3 h 2 ITC 7. If doctors are truly good at diagnosis and treatment, the way they relate to patients is not that important 0.9 41.6 0.577 0.060 0.061 0.340 0.428 16. It is not that important to know a patient’s culture and background in order to treat the person’s illness 0.3 52.4 0.476 0.065 0.033 0.232 0.356 2. Although healthcare is less personal these days, this is a small price to pay for medical advances 1.3 9.3 0.446 0.045 0.147 0.223 0.376 3. The most important part of the standard medical visit is the physical exam 6.1 1.8 0.425 0.141 0.057 0.203 0.405 11. If a doctors’ primary tools are being open and warm, the doctor will not have a lot of success 1.5 21.5 0.421 0.107 0.058 0.201 0.338 15. The patients must always be aware that the doctor is in charge 4.7 10.5 0.413 0.376 0.175 0.342 0.379 1. The doctor is the one who should decide what gets talked about during a visit 2.0 6.2 0.326 0.117 0.092 0.128 0.307 6. When doctors ask a lot of questions about a patient’s background, they are prying too much into personal matters 0.1 74.9 0.324 − 0.096 0.112 0.127 0.218 9. Patients should be treated as if they were partners with the doctor, equal in power and status 3.1 23.8 0.118 13. A treatment plan cannot succeed if it is in conflict with a patient’s lifestyle or values 4.4 13.6 0.031 18. When patients look up medical information on their own, this usually confuses more than it helps 40.1 0.9 − 0.051 0.650 0.099 0.435 0.416 5. Patients should rely on their doctors’ knowledge and not try to find out about their conditions on their own 21.3 4.0 0.084 0.636 0.082 0.418 0.458 12. When patients disagree with their doctors, this is the sign that the doctor not have the patient’s respect and trust 3.0 13.3 0.260 0.358 0.145 0.217 0.283 * 10. Patients generally want reassurance rather than information about their health 7.6 4.9 0.042 0.141 0.565 0.341 0.277 17. Humor is a major ingredient in the doctor’s treatment of the patient 11.8 3.6 0.134 0.035 − 0.394 0.174 0.180 # 4. It is often best for patients if they do not have a full explanation of their medical condition 1.5 30.8 0.093 0.083 0.358 0.144 0.254 8. Many patients continue asking questions even though they are not learning anything new 2.8 17.9 0.156 14. Most patients want to get in and out of the doctor’s office as quickly as possible 13.1 3.9 0.119 % variance explained 9.9 7.0 5.0 Cronbach’s 0.657 0.566 0.399 ICC 0.704 0.789 0.661 Low/high , % of lowest (1) and highest (6) possible scores; F1/F2 , factor 1 and factor 2 extracted; h 2 , communalities; ITC , item-total correlation; ICC , intraclass correlation coefficient (test–retest reliability); *Cronbach’s α = 0.608 if deleted; # Cronbach’s α =0.411 if deleted; Factor loadings >0.3 are reported in bold Section title: PPOS Factor Structure Educational score: 4.102398872375488 Domain: biomedical Document type: Study Language: en Assumptions of sampling adequacy (KMO measure was 0.748, i.e., middling) and data factorizability were met. In the first round, with the Kaiser-Guttman criterion applied, EFA identified six factors with eigenvalues > 1, explaining 52.2% of the variance. The inspection of the scree plot showed two points of inflection at factors 3 and 4, suggesting to retain two or three factors. The two-factor solution explained 26.6% of the variance, with five items (9, 13, 4, 8, 17) non-retainable due to low loading (< 0.30). The three-factor solution explained 34.4% of the variance and showed slightly higher communalities and higher loadings than the former, with four non-retainable items (9, 13, 8, 14). Considering these little improvements, the solution found with Kaiser’s criterion and the large sample size, three factors were retained in the final second round of EFA. Table 1 shows factor loadings and communalities of the three-factor solution. Section title: Reliability Analysis Educational score: 4.0220842361450195 Domain: biomedical Document type: Study Language: en Internal consistency was questionable for factor 1 ( a = 0.657), poor for factor 2 ( a = 0.566), and unacceptable for factor 3 ( a = 0.399). Item-total correlations for factor 1 and factor 2 were > 0.3, except for item 6 (ITC = 0.218) and item 12 (ITC = 0.283). Item total-correlations for factor 3 were all < 0.3. Test–retest reliability was acceptable for factor 1 (ICC = 0.704) and factor 2 (ICC = 0.789) and questionable for factor 3 (ICC = 0.661). Details of reliability analysis are provided in Table 1 . Section title: Construct Validity Educational score: 4.164857864379883 Domain: biomedical Document type: Study Language: en PPOS items were not strongly correlated with JSE, FATCOD-9IT, and PSS total scores. As expected for convergent-discriminant analysis, significant medium-to-weak correlations were found between PPOS items and JSE total score (except for items 4, 10, 14, 18), significant small correlations were found between few PPOS items (i.e., 6, 12, 14, 15, 15, 17) and FATCOD-9IT total score, whereas non-significant correlations were observed between PPOS items and PSS total score. Details of correlation analysis are provided in Table 2 . Table 2 Bivariate correlations of the Patient-Practitioner Orientation Scale (PPOS) items and sums of scores of the Jefferson Scale of Empathy (JSE), the 9-item version of the Frommelt Attitude Toward the Care Of the Dying (FATCOD-9IT) Scale, and the Perceived Stress Scale (PSS) PPOS item JSE FATCOD-9IT PSS 1 0.188** 0.019 − 0.011 2 0.298** 0.032 0.028 3 0.245** 0.012 0.046 4 0.047 0.062 0.025 5 0.097** 0.030 0.027 6 0.191** 0.110** − 0.046 7 0.434** 0.048 − 0.084 8 0.143** 0.033 − 0.013 9 − 0.289** 0.015 0.078 10 0.023 0.071 − 0.019 11 0.324** − 0.055 0.070 12 0.122** 0.095* 0.009 13 − 0.143** − 0.044 − 0.040 14 0.032 0.120** − 0.020 15 0.194** 0.077* 0.068 16 0.373** 0.090* 0.097 17 − 0.329** 0.081* 0.101 18 0.049 0.044 0.011 Pearson r < 0.30 indicates weak correlation; * p < 0.05; ** p < 0.01 Section title: Construct Validity Educational score: 4.216678619384766 Domain: biomedical Document type: Study Language: en Research hypotheses developed about between-group differences on PPOS were confirmed. MANOVA showed significant effect of gender ( p < 0.001), preferential interest ( p < 0.001), and setting ( p < 0.001) in medical practice on PPOS score. Female students and those who had declared themselves more interested in humanistic and relational aspects of medical practice and prone to outpatient practice scored higher on the PPOS than males and those who demonstrated more interest toward technical and interventional medical procedures (see Table 3 ). MANOVAs showed significant effect also of age ( p = 0.007) and psychological wellbeing ( p = 0.044) on PPOS score, with follow-up univariate analyses mostly non-significant (except for psychological wellbeing on factor 1). Details of MANOVA are provided in Table 3 . Table 3 Between-group differences on Patient-Practitioner Orientation Scale (PPOS) score Variable Λ Part η 2 F1 p F2 p F3 p Gender 0.936** 0.033 < 0.001 0.001 0.060 Male 4.2±0.6 2.8±0.9 3.6±0.8 Female 4.5±5.6 2.9±0.9 3.7±0.7 Age group 0.987* 0.006 0.058 0.497 0.025 18–19 4.4±0.6 2.8±0.9 3.7±0.7 20–21 4.4±0.6 2.9±0.9 3.7±0.7 > 22 4.5±0.6 3.0±0.9 3.5±0.8 Interest in medical practice 0.915** 0.085 Doctor-patient relationship 4.6±0.6 < 0.001 2.9±0.9 0.139 3.7±0.7 0.023 Technical aspects and interventions 4.2±0.5 2.9±0.9 3.6±0.7 Setting in medical practice 0.970** 0.030 < 0.001 0.186 0.516 Examination room 4.5±0.6 2.9±0.9 3.7±0.7 Operating room/lab 4.3±0.6 2.9±0.9 3.6±0.7 Psychological wellbeing (quartiles) 0.991* 0.005 0.010 0.891 q 0.409 Lower 4.5±0.6 2.9±0.9 3.7±0.7 Middle 4.4±0.6 2.9±1.0 3.6±0.7 Upper 4.3±0.6 2.9±0.9 3.6±0.7 Λ , Wilks’ lambda; * p < 0.05; ** p < 0.01; Part η 2 , partial eta squared; F1/F2 , factor 1 and factor 2 extracted Section title: Discussion Educational score: 4.158797264099121 Domain: biomedical Document type: Study Language: en Although the PPOS has been widely used in healthcare and medical education research in the last two decades, its psychometric properties have not yet been fully ascertained and its factor structure is still discussed. Since it is the only tool available to date to assess patient-centeredness attitudes of healthcare students and professionals, further research was required, also to shed more light on factors affecting doctors’ patient-centered behavior. In detail, the aim of this study was to investigate the PPOS reliability, factor structure, and construct validity on a large sample of undergraduate medical students. Taken together, results of this study showed that the PPOS has psychometric limitations when used to measure patient-centeredness among first-year medical students (Q1), the assumption of two-dimensionality for the scale construct is not respected in this population (Q2), and the scale adequately differentiates the patient-centeredness based on gender, preferential interest, and setting toward medical practice (Q3). These findings suggest that the PPOS 18-item version might contain items with poor validity and the construct it intends to measure is quite weak and unstable, as it changes when assessed in different populations. These results corroborate previous observations and strengthen the need for scale revision . Section title: PPOS Construct Dimensionality: A Comparison with the Literature Educational score: 4.243849754333496 Domain: biomedical Document type: Study Language: en Findings from reliability and item analysis suggest that PPOS includes a cluster of items with poor validity, having little variance in common, that are not very homogeneous each other, consistently with previous studies . Findings about PPOS factor structure suggest multiple unclear not well separated solutions, as PAF pointed to possible six-, three-, and two-factor structures. The retained three-factor solution, which turned out to be the best in terms of percentage of variance explained and item numerosity observed in this study, nonetheless evidenced poor definition and functioning of many items, given low communality values and low factor loadings (items 9, 13, 8, 14 and were excluded from the final solution due to loadings < 0.30 and item 15 loaded on two factors), suggesting the weakness of scale construct. In the three-factor solution found in this study, F1 consisted of eight items (1, 2, 3, 6, 11, 15, 16) in partial overlap with the Caring dimension of the original PPOS, with the exception of items 1 and 15; F2 consisted of three items (8, 12, 15) all belonging to the Sharing dimension in the original PPOS; and F3 consisted of three items (4, 10, 17), of which the former two belonged to the Sharing dimension whereas item 17 belonged to Caring dimension in the original PPOS . According to the PAF performed in this study, F1 seems to refer to the doctor’s relational style and disposition to be welcoming to the patient; F2 seems to refer to the doctor’s disposition to share power with the patient; and F3 seems to refer to the doctor’s disposition to be protective of the patient. F1 is the better-defined factor, more numerous and reliable, that matches the Caring dimension of the original PPOS, and is generally preserved in most studies [ 15 , 17 – 21 ]. F2 and F3 were found to be less defined, numerous, and reliable. Items in these factors were observed to be mixed in previous studies , suggesting that the Sharing dimension may be weaker and questionable. The items excluded from the final factor solution seem to be part of a critical and uncorrelated cluster with low ITCs and inter-item correlations; items 9 and 13, two of the three statements phrased in patient-oriented style, were excluded also in previous studies , and items 8 and 14 were not retained in confirmatory factor analysis due to poor statistical indexes in PPOS shortening validation studies . Moreover, item 17, retained in this study even though its deletion would have increased F3 internal consistency, was deleted in multiple studies . Section title: PPOS Affordability Based on Medical Training Educational score: 4.126725196838379 Domain: biomedical Document type: Study Language: en In addition to the documented psychometric weakness of the PPOS, one of the possible reasons behind the inconsistency of the construct the scale intends to measure could concern the instrument was designed and used to assess attitudes in population highly different in training, experience, and role, including healthcare students at different stages of their curricula (preclinical vs clinical), physicians, nurses, and patients. As correctly argued by Jiang and colleagues, understanding the concept of patient-centeredness and acknowledging the way of behaving in accordance with it is not the same as acting the attitude in clinical work . In this study, first-year medical students asked to give an opinion on the statements of the PPOS, appeared to respond with confidence to the items of the Caring dimension, and seemed they were in trouble providing a personal evaluation on the items of the Sharing dimension. This should not be surprising, as while the Caring attitude reflects the purpose of the medical practice, in which the motivation to become a doctor of many young medical students is rooted, the Sharing attitude deals more with experience in clinical practice and the development of a personal clinical style. If so, the malfunctioning of F1 and F2 observed in this study might be due to its use with preclinical medical students. Section title: PPOS and Related Constructs Educational score: 3.16304612159729 Domain: biomedical Document type: Study Language: en Findings from convergent-discriminant analysis showed the construct the PPOS measures correlates with empathy for patient care and attitude toward the care of the dying, while remaining distinct from them, and does not correlate with perceived stress, according with research hypotheses. Lastly, PPOS showed satisfactory measurement invariance across age and psychological wellbeing groups, according to research hypotheses. Section title: Limitations Educational score: 2.98052716255188 Domain: biomedical Document type: Study Language: en This study has some limitations that must be mentioned. First, considering the lack of confirmatory analysis, findings about the PPOS three-dimensional model need to be confirmed in future studies. Second, the convenience sampling used in this study limits the generalizability of its findings. Third, the exclusive use of self-report measures does not allow to determine to what extent the data captured accurately reflects the participants’ real attitudes, beliefs, and future behaviors. Section title: Conclusion Educational score: 4.089889049530029 Domain: biomedical Document type: Study Language: en Findings in this study support the conclusion that the 18-item version of the PPOS has psychometric limitations as regard reliability and item validity. Moreover, the robustness of the underlying construct is not proven. This means that it should be used with caution when assessing first-year medical students’ patient-centeredness. Further studies are needed to address these limitations, confirm the multidimensionality of scale construct, and ascertain that previous attempts of scale shortenings have not caused loss of content and original construct validity. | Review | biomedical | en | 0.999996 |
PMC11699140 | Section title: Introduction Educational score: 3.7752444744110107 Domain: biomedical Document type: Other Language: en Tumor boards, characterized by their convergence of diverse medical professionals and complex patient cases, represent an untapped educational resource for undergraduate medical students. The multidisciplinary nature of these boards has been shown to improve patient outcomes across a spectrum of cancers, in both adult and pediatric settings, and in diverse socio-economic contexts, from high-income to resource-limited settings [ 1 – 6 ]. This global and inclusive perspective is particularly relevant for medical students, who will be practicing in an increasingly interconnected and diverse world . Section title: Introduction Educational score: 1.6739541292190552 Domain: other Document type: Other Language: en Nevertheless, simply being present at these meetings is not enough to harness their educational potential. Navigating this complex learning environment requires a strategic, structured approach that goes beyond passive observation. It is essential to foster active learning, critical thinking, reflection, and a nuanced understanding of the roles and dynamics within a multidisciplinary team . Section title: Introduction Educational score: 3.933479070663452 Domain: biomedical Document type: Study Language: en This paper presents a roadmap of 12 strategies to achieve these educational goals. By engaging with the rich, real-world learning environment of tumor boards, students can gain a deep understanding of the collaborative, patient-centered, and evidence-based approach that underpins successful oncological care. These strategies serve as a guide to transform the tumor board experience into a dynamic, immersive learning journey for students, equipping them with the knowledge, skills, and attitudes necessary for effective contribution within a multidisciplinary team. The 12 strategies proposed in this paper are synthesized from a comprehensive review of existing literature and best practices. Section title: Incentivize Active Engagement Educational score: 3.219609498977661 Domain: biomedical Document type: Other Language: en Encourage students to participate actively by assigning tasks that align with their level of expertise — summarizing patient histories or presenting relevant research findings. Active engagement stimulates critical thinking, promotes problem-solving skills, and instills a sense of responsibility towards their learning journey . Moreover, this participation fosters reflection on interprofessional interactions, encouraging students to consider how their contributions are influenced by the multidisciplinary team . Research suggests that such active engagement in multidisciplinary meetings significantly enhances learning experiences . Section title: Foster a Question-Friendly Environment Through Open Discussion Forums Educational score: 1.9431623220443726 Domain: biomedical Document type: Other Language: en Facilitate open discussion forums where students feel safe to ask questions, share insights, and express their thoughts about the tumor board meetings. These forums can be held in a round-table format, with a faculty member acting as a facilitator to ensure respectful and constructive dialogue. Such an environment encourages active participation, enhances understanding, and fuels critical thinking . Section title: Deepen Learning Through Structured Case-Based Discussions Educational score: 3.305405616760254 Domain: biomedical Document type: Other Language: en Enhance the learning experience with structured, post-meeting case-based discussions. Select complex, multi-faceted cases from tumor boards for in-depth exploration in smaller student-led discussion groups. These discussions can delve into the nuances of each case, allowing students to critically analyze the patient history, evaluate diagnostic options, devise potential treatment strategies, and anticipate challenges in patient management. They also provide a platform for students to reflect on how multidisciplinary inputs shape the understanding and management of a case, thereby highlighting the value of diverse professional perspectives in patient care . Section title: Foster Skills for Patient Education and Counseling through Structured Clinical Experiences Educational score: 3.4795379638671875 Domain: biomedical Document type: Other Language: en Where possible, arrange for students to have direct interactions with patients whose cases are being discussed in the tumor board. These interactions could involve taking a patient history, conducting a physical examination, or discussing the patient’s experiences and perspectives about their illness. Such experiences can provide invaluable insights into the patient’s perspective, enhancing empathy and grounding students’ learning in real-world clinical practice . Supplement this learning with opportunities to interact with patients in a clinical setting under supervision, where students can see the real-life implications of the decisions made during tumor boards. These experiences will help students understand the critical role of patient-centered care in shaping clinical decisions and outcomes. Section title: Implement Reflective Writing Exercises Educational score: 3.7426810264587402 Domain: biomedical Document type: Other Language: en Post-meeting reflective writing exercises can serve as a powerful tool for consolidating learning and fostering self-awareness . Encourage students to maintain a reflective journal where they can record their observations, thoughts, and questions about each tumor board meeting. The journal entries can focus on a variety of aspects such as the complexity of the cases, the interprofessional dynamics observed, the ethical dilemmas encountered, and the decision-making processes followed. Additionally, they should reflect on their own contributions and interactions within the team and how these experiences are shaping their understanding of oncology and their professional development. The journals can be reviewed periodically with a faculty mentor to provide feedback and guide further learning. Reflective writing has been recognized in medical education literature as an effective method for promoting critical thinking, self-awareness, and professional growth . Section title: Integrate Digital Learning Tools for Augmented Learning Experiences Educational score: 3.530035972595215 Domain: biomedical Document type: Other Language: en Incorporate digital learning tools specifically designed to augment the tumor board learning experience . Utilize online platforms for curating a library of key cases discussed in the tumor board, complete with anonymized patient histories, diagnostic images, pathology reports, and summaries of the decisions made . This can serve as a valuable resource for self-directed learning and future reference. Further, create a protected online discussion forum dedicated to each tumor board meeting. Here, students can continue the discussion beyond the meeting, share additional research findings, pose unanswered questions, and engage in peer learning . Faculty members can participate in these forums, providing guidance and feedback and addressing student queries. These digital initiatives can offer a flexible, diverse, and multifaceted learning environment, catering to the varied learning preferences of today’s digital-native students . By integrating digital tools into the tumor board learning experience, we can enhance student engagement, foster active learning, and ensure continuous feedback and improvement . Section title: Showcase the Spectrum of Interprofessional Collaboration Educational score: 2.718984842300415 Domain: biomedical Document type: Other Language: en Expose students to the various roles within the tumor board through shadowing experiences. These opportunities can demystify the unique contributions of each team member to patient care, enhance understanding of team functioning, and expose students to the nuances of team communication, hierarchy, and negotiation . Reflection on these experiences can foster a deeper appreciation for the diversity of professional roles . Such interprofessional education experiences have been highlighted in research as valuable in preparing future physicians for collaborative practice . Section title: Demystify the Multidisciplinary Decision-Making Process Educational score: 3.5710344314575195 Domain: biomedical Document type: Other Language: en Transform the seemingly complex decision-making process of tumor boards into a structured learning experience . Begin by deconstructing previous decisions made during tumor boards, spotlighting how patient preferences, clinical guidelines, research evidence, and professional expertise are collectively considered . Also, highlight the role of effective communication, mutual respect, and consensus building within the team . Then, facilitate student participation in this process by creating mock decision-making scenarios, for example, through the implementation of tactical decision games, enabling them to apply these principles in a safe learning environment . Section title: Cultivate Critical Reflection on Interprofessional Interactions through Reflective Debriefing Educational score: 3.2184696197509766 Domain: biomedical Document type: Other Language: en Promote a culture of critical reflection on the nature and quality of interprofessional interactions within the tumor board [ 33 – 35 ]. Implement structured reflective debriefing sessions after each tumor board meeting, where students can share their observations about the dynamics of teamwork, the communication patterns they noticed, and the process of collaborative decision-making. These sessions can be facilitated by a faculty member who can provide insights, clarify misconceptions, and guide students in deriving learning from these reflections. Section title: Reinforce the Importance of Evidence-Based Practice through Research Appraisal Exercises Educational score: 2.702666997909546 Domain: biomedical Document type: Other Language: en To nurture a culture of evidence-based practice, incorporate research appraisal exercises into the learning plan. Assign students recent research articles related to the cases discussed in the tumor board and guide them in critically appraising the methodology, results, and applicability of the research findings. This not only enhances their research literacy but also highlights the application of research in clinical decision-making . Section title: Emphasize Patient-Centered Care Educational score: 3.4635915756225586 Domain: biomedical Document type: Other Language: en Patient-centered care is a crucial aspect of modern healthcare and a key element in the proceedings of a tumor board . While patients themselves may not be physically present in these meetings, their experiences, preferences, and needs are central to the discussions . As such, it is essential that students understand how to place the patient at the center of their learning experience within the tumor board context . Encourage students to review each patient’s history, imaging, pathology, and the psychosocial aspects of their case critically. Highlight how the unique aspects of each patient’s case — their comorbidities, lifestyle, personal preferences, and social circumstances — influence the diagnostic and treatment decisions made during the tumor board. Section title: Highlight Ethical Considerations Educational score: 3.968924045562744 Domain: biomedical Document type: Other Language: en In oncology education, particularly within tumor board discussions, it is crucial to emphasize holistic ethical considerations, for example, by integrating the concept of “total pain” alongside traditional ethical dilemmas. Total pain, a term coined by Cicely Saunders, refers to the multifaceted nature of pain experienced by patients, encompassing physical, psychological, social, and spiritual dimensions . Use the cases to bring ethical considerations in oncological care such as informed consent, patient confidentiality, end-of-life decisions, and balancing treatment benefits and harms to the forefront . Encourage students to reflect on these aspects in dedicated ethics sessions, guiding them to understand the complexity of patient suffering and ethical decision-making in oncology. This approach, incorporating both conventional ethical dilemmas and the broader concept of total pain, aims to develop healthcare professionals who are not only ethically astute, able to reflect on these issues, debate differing viewpoints, and develop their own reasoned stance, but also deeply empathetic towards the multifaceted suffering of their patients . Section title: Conclusion Educational score: 4.021220684051514 Domain: biomedical Document type: Study Language: en In conclusion, the integration of medical students into tumor board discussions presents a multifaceted opportunity to enhance their learning experience, equipping them with the skills and knowledge necessary for effective interdisciplinary collaboration in oncology care. This paper has outlined a comprehensive strategy, centered around active engagement, structured learning, patient interaction, reflective practice, and the use of digital tools, to maximize the educational potential of tumor boards. These strategies aim to foster a deep understanding of the complexities of cancer care, emphasizing the importance of evidence-based practice, patient-centered approaches, and ethical considerations. By engaging students in this dynamic, real-world context, we not only prepare them for their future roles in healthcare teams but also contribute to the cultivation of a more collaborative, informed, and compassionate oncology workforce. Section title: Conclusion Educational score: 2.517301082611084 Domain: biomedical Document type: Other Language: en Nevertheless, it is essential to acknowledge the practical realities of tumor boards. These meetings are primarily work-focused, designed to discuss as many patients as efficiently as possible . This fast-paced environment can pose significant challenges for educational integration, such as time constraints and the need to balance thorough discussion with efficiency . Recognizing these challenges, it is crucial for educators to strategically plan student involvement, ensuring that their educational needs are met without disrupting the primary objectives of the tumor boards. Solutions may include preparatory sessions, selective participation in discussions, and post-meeting debriefings to maximize learning while maintaining the efficacy of the meetings. Section title: Conclusion Educational score: 3.7292630672454834 Domain: biomedical Document type: Other Language: en The emphasis on interprofessional education within tumor boards underscores the necessity for future physicians to navigate and contribute to multidisciplinary teams effectively. The skills developed through such exposure—critical thinking, effective communication, ethical reasoning, and empathetic patient care—are fundamental to the practice of medicine and transcend the specific context of oncology. As medical education evolves, the incorporation of such experiential learning opportunities as tumor boards will be crucial in preparing students for the complexities of modern healthcare delivery. Section title: Conclusion Educational score: 3.9168312549591064 Domain: biomedical Document type: Other Language: en Ultimately, this approach aligns with the broader objectives of medical education to produce healthcare professionals who are not only clinically competent but also capable of addressing the multifaceted challenges of patient care in a collaborative, ethical, and patient-centered manner. The strategies presented herein, therefore, not only enhance the educational value of tumor boards for medical students but also serve as a model for integrating experiential learning across the medical curriculum. As we continue to explore and refine these methodologies, it is imperative that we evaluate their impact on student learning outcomes and patient care, ensuring that our educational practices remain aligned with the evolving needs of our healthcare systems and the patients they serve. | Other | biomedical | en | 0.999997 |
PMC11699163 | Section title: Background Educational score: 4.0542988777160645 Domain: biomedical Document type: Review Language: en Many medical schools in the past 20 years have integrated team-based learning (TBL) into their medical curriculum [ 1 – 5 ]. In fact, the AAMC reported that approximately 54% of medical schools utilized TBL in the 2019–2020 academic year . Historically, the TBL structure is as follows: pre-class preparation, individual readiness assurance test (IRAT), team readiness assurance test (TRAT), immediate feedback/clarification, and clinical problem-solving activities . The pre-class preparation typically involves the use of pre-reading or online lectures as prework for the TBL in the medical curriculum . The use of TBL in the preclinical years of medical education has been shown to provide many benefits including improved performance on exams and positive student feedback . A study from Carrasco et al. concluded “team-based learning scores and participation are better predictors of successful course performance than case-based learning performance” . Section title: Background Educational score: 4.005467891693115 Domain: biomedical Document type: Study Language: en The AAMC reported that approximately 97% of medical schools utilized case-based learning (CBL) in the 2019–2020 academic year . Though an extremely popular method of medical education, the use of CBL as preparation for TBL is less widely used and largely unstudied . Creighton University School of Medicine (CUSOM) has modified the typical structure to use CBL as prework and preparation for TBL instead of the traditional TBL pre-reading or online recordings . Students at CUSOM first work through the clinical aspects of a case with their small group in CBL. Then, students attend a TBL based on the material presented in the CBL. Students are tested individually and as part of their team/small group. In this approach, TBL assesses the material that students learn with their small group in CBL, leading us to question the relationships between aspects of learning in CBL and performance in TBL. Though students at CUSOM spend the majority of time learning from traditional lectures, students complete one to three TBL’s per week, making up a significant portion of their instruction. Section title: Background Educational score: 2.0695512294769287 Domain: biomedical Document type: Other Language: en Guidelines for TBL are published in the student handbook and generated by the Office of Medical Education. This guideline, however, does not contain any requirements or expectations regarding CBL as preparation for TBL, leaving small groups with free direction to complete the case as they wish at a pace set by the group. Additionally, there is no graded component tied to the completion of the CBL. Aside from the first four cases of the M1 year, there is no direct faculty participation or oversight in the small group setting. Given the lack of direct oversight, there may be a tendency for groups to rush through or sidestep difficult aspects of the case to complete the task more quickly, significantly hindering both the individual student’s and group’s learning. Section title: Background Educational score: 2.4818179607391357 Domain: biomedical Document type: Study Language: en Given CUSOM’s novel approach of using CBL in preparation for TBL, we aimed to evaluate the relationship between the time spent in CBL, performance on the TBL, including IRAT and TRAT scores, and performance on final exam questions assessing the content of the CBL. Section title: Activity Educational score: 4.142374038696289 Domain: biomedical Document type: Study Language: en Student data from two medical campuses of CUSOM were collated to examine the relationship of the identified variables from 29 cases across 6 courses throughout the academic year 2022–2023 that met inclusion criteria as discussed below. Data from the Omaha campus included the entire M2 cohort that consisted of 128 students in the M2 year. Data from the Phoenix campus included the entire M2 cohort that consisted of 99 students in the M2 year. The following variables were collected: time spent in CBL (in minutes; extracted from the learning management system), IRAT and TRAT performance (extracted from Intedashbaord), and exam performance on related questions (extracted from ExamSoft). Of note, exam performance refers only to final exam questions that tested material directly related to CBL/TBL sessions, not to overall final exam performance in the course. CBL cases are available through the learning management system which requires students to click through the case in order to reach the next step of the case. Once the team has completed the case, a student moderator must hit submit in order to see the correct answers for questions that were completed throughout the case. With the submission of the case, completion time is recorded. Data was merged by student ID and then de-identified. Case times were calculated by subtracting the start time recorded from the completion time recorded. Outliers with respect to time (longer than 160 min for a scheduled 120-min time slot) were removed. Only cases with associated exam questions were included in analysis. A mean score for each variable across all cases was computed for each student, taking the final score from each relevant case and finding the mean average across all cases for IRAT, TRAT, and exam data. Data was transformed through centering and standardization, resulting in z -score data for each observation of each variable to allow for easier interpretation of comparisons. Z -scores were chosen for the variables due to the ease of interpretation with all variables being on the same scale, save for exam scores, which were kept on a 0 to 1 scale as provided in the data; Z -scores also allow for results of regression modeling to be interpreted in standard deviations. Computing variable values to z -scores also prevents additional weight from being assigned to variables on different scales. Section title: Results and Discussion Educational score: 2.8845674991607666 Domain: biomedical Document type: Study Language: en Linear regression was performed on the resulting data for relationships between time spent on the CBL, IRAT performance, TRAT performance, and exam performance. Analysis on the distribution of residuals, the difference between actual and predicted observations, was done to validate model performance on the data. All analysis was carried out in R, with RStudio serving as the integrated development environment. Section title: Omaha Results Educational score: 4.108055114746094 Domain: biomedical Document type: Study Language: en There was a significant relationship between IRAT and exam performance, controlling for time and TRAT scores, with exam performance as the dependent variable (adj. R 2 = 0.42, F (6, 73) = 10.3, p = 0.00). The coefficient from this model was β = 0.40, indicating that a 1 standard deviation increase in IRAT score would lead to an approximately 0.40 standard deviation increase in exam score . Predictions of these exam performances resulted in a distribution of residuals with a rightward skew, indicating a higher-than-observed estimation by the model for exam scores based on IRAT scores and controlling for time and TRAT scores . This data supports previous research showing a strong correlation between TBL performance and final exam performance when compared to other learning methods . Fig. 1 Distribution of estimated effect sizes from the chosen model Fig. 2 Approximate normal distribution of residuals for the chosen model, with the rightward skew indicated by the points above the trend line on the lower left and below the trend line on the upper right portion of the graph Section title: Omaha Results Educational score: 3.2093942165374756 Domain: biomedical Document type: Study Language: en There was not a significant relationship between time and exam performance (adj. R 2 = 0.00, F (1, 78) = 1.02, p = 0.317). There was not a significant relationship between average time and average IRAT performance (adj. R 2 = 0.00, F (1, 78) = 1.07, p = 0.30). There was not a significant relationship between average time and average TRAT performance (adj. R 2 = 0.00, F (1, 78) = 13.12, p = 0.71). This indicates that exam performance, average IRAT performance, and average TRAT performance cannot be predicted by the average time spent on the case. Section title: Phoenix Results Educational score: 4.1274824142456055 Domain: biomedical Document type: Study Language: en There was a significant relationship between average IRAT and average exam performance, controlling for time and mean TRAT scores, with exam as the dependent variable (adj. R 2 = 0.33, F (3, 70) = 13.12, p < 0.01). The coefficient from the model was β = 0.18, indicating that a 1 standard deviation increase in mean IRAT score would lead to an approximately 0.18 standard deviation increase in mean exam score . Predictions of these exam performances resulted in a non-normal distribution of residuals, indicating that not all patterns within the data between mean IRAT scores and mean exam scores, when controlling for time and mean TRAT performance, were captured by the model. Figure 4 also indicates that there may exist outliers in the tail end of the residual distribution. Fig. 3 Distribution of estimated effects sizes from the chosen model Fig. 4 Non-normal distribution of residuals for the chosen model, shown by small systematic deviations near center of distribution. An outlier exists in the rightward tail of the distribution Section title: Phoenix Results Educational score: 3.7880642414093018 Domain: biomedical Document type: Study Language: en There was not a significant relationship between average time and exam performance (adj. R 2 = 0.00, F (1, 72) = 0.46, p = 0.50). There was not a significant relationship between IRAT average performance and average time (adj. R 2 = 0.00, F (1, 105) = 0.46, p = 0.78). There was a significant relationship between TRAT average performance and average time (adj. R 2 = 0.03, F (1, 105) = 4.25, p = 0.04). However, a low coefficient of determination indicates that very little variation in average TRAT scores can be explained by average time. These results indicate that exam performance and average IRAT and TRAT performance cannot be predicted by average time spent on the case. Section title: Phoenix Results Educational score: 1.4023998975753784 Domain: other Document type: Study Language: en Similar results were found in Omaha and Phoenix with respect to average IRAT performance being significantly related to exam performance, with a larger effect on exam performance on the Omaha campus. Average TRAT performance was not significantly related to average time in Omaha, but it was in Phoenix albeit a low coefficient of determination. There was not a significant relationship between IRAT results and average time on either campus. Section title: Phoenix Results Educational score: 1.7729194164276123 Domain: other Document type: Study Language: en Though previous research has found a relationship between TBL participation and IRAT scores, participation was defined as the amount of time a student spoke during the activity . Given CUSOM’s use of CBL as pre-work for TBL, we considered time spent in CBL as an alternative variable that may be comparable to participation in the classical TBL model. Though student participation and time spent in CBL cannot be directly equated, it is assumed that the longer a group spends completing CBL, the greater the amount of participation of the students in the group. Therefore, we expected to see a relationship between performance and time spent in CBL. However, our data demonstrated no relationship between time spent on CBL and individual performance on TBL and exams. Therefore, it cannot be assumed that case time will act as a strong predictor of assessment performance. Section title: Phoenix Results Educational score: 1.8821696043014526 Domain: other Document type: Study Language: en Faculty and educators at CUSOM have made efforts to improve the quality and experience of the CBL’s, often focusing on the time and experience of the CBL. This research indicates that increasing time spent in the CBL may not have an impact on students. Our data suggests that there is no correlation between time spent completing CBL and performance on IRAT and exam questions. Though a relationship was found between time spent completing CBL and performance on TRAT at the Phoenix campus, it explains very little of the variation in TRAT scores. This would indicate that setting protocols relating to time may not provide any direct benefit to student academic performance. Future research should consider the time students spend studying outside of CBL and TBL. It is possible that students who move through the CBL at a faster pace spend more time individually studying as preparation for TBL and, therefore, perform just as well as groups who engaged in more discussion throughout CBL. Future research could help to refine the understanding of the relationship between time and performance. Section title: Phoenix Results Educational score: 2.1743581295013428 Domain: biomedical Document type: Study Language: en This study was conducted at a single institution. While this limits generalizability, this research also provides a framework for future research in this area. Some case times were missing from the data; z -score mean imputation was used to counter this issue. Results are limited to the group time submitted in the CBL, and it is possible that some individuals would have spent more or less time engaged with the material. There are many other aspects to CBL and TBL that may also influence performance, which could not be studied in this particular study, including but not limited to, student background knowledge, English as a second language, student participation in both CBL and TBL, and preferred learning method. Section title: Phoenix Results Educational score: 3.7428784370422363 Domain: biomedical Document type: Study Language: en Overall, our findings suggest that there is a relationship between performance on TBL and exam performance. Our data supports previous literature indicating better course performance stemming from these active learning methods . We found no statistical relationship for time spent on CBL and related assessment performance, which may provide valuable feedback to medical educators on the use of CBL and TBL in preclinical medical education. | Review | biomedical | en | 0.999994 |
PMC11699177 | Section title: Background Educational score: 4.008486747741699 Domain: biomedical Document type: Review Language: en Patient cases are important and widely used in healthcare education . Within undergraduate medical education, cases are an integral aspect of case-based learning (CBL) and problem-based (PBL) modalities. CBL, an example of active learning, has been shown to have benefits over standard lecture and team-based learning [ 1 – 5 ]. Many medical schools have adopted some form of CBL in their curricula and face the challenge of developing, maintaining, and updating their own teaching cases. Resources have been published and can help guide the process of developing and evaluating individual cases . There is also guidance for improving diversity, inclusion, and equity in curricular materials in medical education [ 8 – 13 ]. Core attributes of effective individual cases have been identified as relevant, realistic, engaging, challenging, and instructional . When individual cases are combined to create a case catalog, desired attributes should be expanded to include being consistent, current, diverse and inclusive, patient-centered, and mission-centered . Section title: Background Educational score: 4.02677583694458 Domain: biomedical Document type: Study Language: en While the overall effectiveness of PBL and CBL as learning modalities has been studied, limited data are available on the effectiveness of the cases themselves, which can take a variety of forms and be used differently at each institution [ 1 – 5 ]. Similarly, most published student feedback on CBL appears to be focused on the overall CBL experience rather than the content or quality of the teaching cases . The University of Ottawa used medical student perspectives of the positives and negatives of their cases to develop a detailed tool for creating and reviewing CBL cases, focused primarily on case structure and inclusion of factual information on pathophysiology, differential diagnosis, and treatment . As many medical schools move to integrate more clinical aspects into pre-clerkship curricula, student perspectives on effectiveness of CBL cases that include communication skills, ethics, professionalism, and person-centered care are important. Section title: Background Educational score: 2.6679930686950684 Domain: biomedical Document type: Other Language: en At our institution, faculty have worked to integrate clinical and foundational science content of our pre-clerkship medical curricula that emphasizes student-directed, case-based small groups that work through one case weekly in year 1 and two cases weekly in year 2. The small groups usually consist of eight medical students and two faculty facilitators, typically a physician and a basic scientist. The groups meet for 2-h sessions three times per week to go through cases, generate learning agendas, share student learning summaries, and take part in case presentations and case role plays. During the COVID-19 pandemic, there were no changes to the structure or process of these groups other than meeting virtually. Section title: Background Educational score: 3.700518846511841 Domain: biomedical Document type: Study Language: en Given the centrality of the cases to our curriculum, a case oversight team was established in 2018 to design and implement a case catalog quality improvement process, a key component of which was the collection and use of student feedback . We initially prioritized humanizing case patients, increasing case patient diversity, and updating diagnosis and treatment details. We also made the cases more complex and realistic with increased coverage of social determinants of health, mental health concerns, ethical and professionalism topics, and modeling of communication and patient education. Additionally, we increased coverage of primary care scenarios, supporting the mission of our institution to produce more primary care doctors for our state. We report here the thematic analysis of qualitative case feedback obtained from multiple cohorts of medical students to identify themes for high-quality CBL cases to improve learning and guide systematic improvements in a pre-clerkship case catalog. Section title: Activity Educational score: 1.8680490255355835 Domain: biomedical Document type: Other Language: en Student feedback on patient cases used in the pre-clerkship curricula is an important source of information for case revision at our institution. Student groups complete an online form at the end of each week where they answer two questions about each case: “Which aspects of the case most effectively facilitated your learning, and why?” and “Which aspects of the case could be improved?”. Section title: Activity Educational score: 2.381891965866089 Domain: other Document type: Study Language: en To identify themes, we first compiled the weekly, anonymous, free-text student feedback from late spring 2018 through December 2021. The overall group feedback response rate was 89% across the 206 weekly opportunities for group feedback over the study period. Our campus class size increased from 40 to 60 students during this time, so feedback was solicited from the five to eight groups in each of the M1 and M2 classes, each composed of seven to nine students. These data were organized by each academic year and student cohorts (i.e., year 1 and year 2). Two team members used an inductive analysis approach to develop 535 in vivo codes, combine the initial codes into 30 broader categories, and then re-code data using the categories to generate themes. When representing the voices of participants is important, using an inductive, constant-comparative approach for data analysis is suggested . This ensured that the perspectives of the students were fully represented in the presentation of the themes. Themes regarding the aspects of the cases that facilitated their learning and aspects that could be improved were identified within years 1 and 2, and then across both years 1 and 2. Section title: Results and Discussion Educational score: 2.8490700721740723 Domain: biomedical Document type: Other Language: en Pre-clerkship student feedback across years 1 and 2 revealed three leading characteristics of cases that facilitated learning : inclusion of high-quality media (e.g., images, audio, video), complexity with rich details, and realism. In addition, year 1 students appreciated when the cases aligned with other curricular components (e.g., gross anatomy, clinical skills), and year 2 students valued incorporating psychosocial/contextual factors (e.g., ethics, social determinants), fostering the development of broad differentials, and curricular reinforcement. Fig. 1 Case aspects that facilitated learning Section title: Results and Discussion Educational score: 4.1295928955078125 Domain: biomedical Document type: Study Language: en Themes for suggested improvement from both years included requests for more media, clarifying/adjusting lab information, and more details to increase complexity and realism. Year 2 students also requested clarification of treatment rationale and details. Example quotes illustrating the themes are provided in Table 1 . Fig. 2 Case aspects for improvement Table 1 Sample quotes illustrating case themes Case aspects that facilitated learning Sample student quotes Inclusion of high-quality media “The imaging was very helpful for understanding the progression of the disease.” “This was our first pediatrics case… and the video demonstrating breathing retractions on physical exam was helpful.” Complexity with rich details “Having two patients with different pathologies helped facilitate the learning. There are various types of brachial plexus injuries, and it was interesting to compare and contrast them. The multigenerational aspect was a nice aspect. It was realistic that Mr. Gonzalez may have sought medical help after seeing similar symptoms in his grandson.” Realism “The case… was relevant to recent events with Covid-19, had a more realistic feel, incorporated complexity of the patient's conditions (i.e., progression of complications), and was relevant to our position as medical students.” Curricular alignment “Having the case correlated directly to a lecture was helpful because it allowed time to think and ask questions outside of group. Having a unique dynamic with a family member that has issues as well was useful and accurate.” Incorporation of psychosocial/contextual factors “We appreciated the inclusion of social determinants of health which facilitated important discussion on behalf of the healthcare provider.” Foster broad differential “Made you consider a large differential… [and] realistic in terms of loss of follow up, [and] ethical/ prognostic factors of chemotherapy.” Curricular reinforcement “Great broad case that covered a lot of material from this week… and some from previous weeks. Great revisiting shock and ARDS. Having to think about the DDx when considering her occupation (nurse) and the etiology of [pneumonia].” Case aspects for improvement Inclusion of more media “Would be nice to see CXR from Wednesday… also an EKG of atrial fibrillation. More pictures please i.e., radiographs, pictures of clinical manifestations.” Clarification/adjustment of lab information “Panel of lab result values to interpret would be useful.” “Would have been nice to have lipase for pancreatic function.” Inclusion of more details to increase complexity and realism “Could be made more complicated by having Sjogrens.” “Could be more realistic in terms of the logistics/difficulties of her initial hospitalization.” Section title: Results and Discussion Educational score: 2.828491449356079 Domain: biomedical Document type: Study Language: en It is striking that the three themes of realism, complexity, and media appeared in both the aspects that facilitated learning as well as areas for improvement. Rather than representing contradictory feedback from different groups, it appears from the specific wording of the quotes that students both appreciated these aspects and requested an increase in quality and quantity. Furthermore, while students earlier in their pre-clerkship training highlighted curricular alignment as important, year 2 students appreciated reinforcement of previous material, accurate clinical management, inclusion of psychosocial/contextual factors, and cases that fostered broad differentials. These differing priorities may reflect the development of the learners throughout the pre-clerkship curriculum. Section title: Results and Discussion Educational score: 4.141320705413818 Domain: biomedical Document type: Study Language: en The importance of realism, complexity, and media in curricular cases were themes in our study and are consistent with existing literature that has identified authenticity, realism, being “engaging and challenging” (i.e., complexity), and use of media as important components of effective case-based learning cases . Although person-centered, diverse, and inclusive attributes have been described as important aspects of CBL cases and case catalogs, it is unclear how commonly these factors are included in standard CBL cases . For our students, inclusion of psychosocial and contextual factors was another positive theme, especially in year 2. In addition, this study documented changes to student priorities as they progressed through the pre-clerkship curriculum with increased interest in differentials, psychosocial factors, treatment, and curricular reinforcement. Careful crafting of cases can provide students with complex and diverse scenarios in which to practice contextualizing pathophysiology and clinical management in the setting of realistic biopsychosocial circumstances. Section title: Strengths and Limitations Educational score: 3.086029291152954 Domain: biomedical Document type: Study Language: en A strength of this study was analysis of extensive data including multiple years of free-text feedback on over 100 individual cases from students at different stages of pre-clerkship training. Another strength was the consistency between coders working with a robust code set to generate themes. The findings reported in this study, as well as the process for obtaining and incorporating feedback, may be applied to other health professions’ case-based curricula at various levels of training. Section title: Strengths and Limitations Educational score: 1.8218919038772583 Domain: biomedical Document type: Study Language: en As our cases are updated each year for continuous quality improvement, one limitation of this study is that it is not possible to directly compare identical cases across years. Therefore, feedback likely changed in response to case revisions, and extracted themes may have evolved. Section title: Strengths and Limitations Educational score: 2.065040349960327 Domain: biomedical Document type: Other Language: en A next step includes analyzing feedback for trends over time. Because each class of students only experiences one version of the cases, future directions include using focus groups of students and faculty to compare different versions of the same cases to more directly assess perceptions of case modifications on learning and preparation for clerkships. Section title: Conclusions Educational score: 4.0367937088012695 Domain: biomedical Document type: Study Language: en To improve learning outcomes, it is important to understand which aspects of curricular cases are highly valued by medical students. This study has demonstrated that increased realism, complexity, and media were strong themes for our pre-clerkship learners. Based on the results of this study, educators could consider a review of cases in their curriculum to ensure they contain valued attributes and are aligned with the curriculum. Medical educators may also consider implementing a process for collecting student feedback to guide systematic case improvements and development of future cases, with an overall goal of promoting the growth of well-rounded physicians who are better prepared to deliver patient-centered care. | Review | biomedical | en | 0.999995 |
PMC11699192 | Section title: Introduction Educational score: 3.8615200519561768 Domain: biomedical Document type: Study Language: en As the artificial intelligence industry continues to gain momentum, there is a rising trend of integrating virtual reality (VR) technology into diverse sectors, including medical education in the form of high fidelity training simulation . Studies show that virtual simulation-based training is effective in teaching procedural medical skills [ 2 – 9 ]. However, during VR experiences, some users may suffer from troublesome symptoms that are similar to motion sickness, termed virtual reality sickness. Motion sickness can potentially affect learning ability. When an individual experiences virtual reality sickness, they may feel nauseous, dizzy, and uncomfortable, which can lead to a range of cognitive and physical effects that may impact the ability to learn . Section title: Introduction Educational score: 4.1695237159729 Domain: biomedical Document type: Review Language: en People rely on different sensory organs to understand orientation and movement. The vestibular, visual, and proprioceptive senses are particularly important in forming a unified perception of self-motion in three-dimensional surroundings. Harmonious processing of all these sensory inputs results in effortless and accurate recognition of position and movement in space. Motion sickness can arise when there is a disparity between visual information and dynamic vestibular input, leading to sensory conflicts between the incoming signals about the current state. When the primary sensory input triggering motion sickness is the visual stimuli, the term visually induced motion sickness (VIMS) is used. The VIMS, depending on the situation, may be called gaming sickness, simulator sickness, cinerama sickness, or virtual reality sickness (VRS) . The VRS is described in the literature by a variety of terms, including cybersickness, simulator sickness, VIMS, and VR-induced symptoms. Prevalence of VRS during or post VR experience has been reported to be as high as 80% . Various factors, including attributes of the intervention itself (such as content and hardware utilized) and individual subjective characteristics, contribute to the determination of VRS symptom severity. According to prior studies, the factors that affect VRS can be classified into VR hardware (the weight, the comfortability, the user interface), the content of the VR simulation (technicality, exposure duration, visual simulation, locomotion), and human-related aspects (prior experiences, eye-related condition, screen time, age, gender) . Section title: Introduction Educational score: 4.029959201812744 Domain: biomedical Document type: Other Language: en One of the significant factors influencing VRS is the user’s familiarity with the head-mounted display (HMD) within the virtual environment and the quality of the simulation training content. Furthermore, in the context of emergency simulation training, various locomotion challenges are encountered. The implementation of appropriate locomotion techniques in VR is imperative to ensure a high level of immersion and a sense of presence while navigating and engaging with the virtual environment . In emergency situations, healthcare professionals are required to possess knowledge and skill concerning machine assembly, equipment operations, vital signs monitoring, communication, and a range of medical competencies. In emergency setting, time is critical and delays in responding or making decisions can have significant consequences in emergency situations. These issues can add more burden to the locomotion challenge they already possessed with virtual reality training. Consequently, visual acuity, spatial awareness, effective communication, and seamless coordination play essential roles and are indispensable for a comprehensive and high-quality training in virtual reality simulation experience for emergency . Section title: Introduction Educational score: 3.2259609699249268 Domain: biomedical Document type: Study Language: en This study is a part of VR-TBI (Virtual Reality-Traumatic Brain Injury) and VR-LAST (Virtual Reality-Local Anaesthetic Systemic Toxicity) project. The project is developed by the Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Universitas Indonesia to evaluate the use of VR technology in emergency simulation training. The purpose of this study is to determine the incidence of VRS in an emergency setting simulation-based training and the related factors, hence providing information and mitigation plan of the virtual reality-related side effects to enhance and optimize learning outcomes. Section title: Study Design Educational score: 3.0817806720733643 Domain: biomedical Document type: Study Language: en This study is a prospective observational study with cross-sectional design that took place in April–June 2023. The target population of our study comprises individuals who voluntarily participate in virtual reality-based simulation training. The study populations, during the designated period, were confined to doctors and doctors in training affiliated with the Faculty of Medicine at the Universitas Indonesia. Section title: Simulation Sickness Questionnaire Educational score: 3.8148610591888428 Domain: biomedical Document type: Study Language: en The Simulation Sickness Questionnaire (SSQ) is used to measure the VRS as the study outcome. It was first derived from the 1983 Motion Sickness Questionnaire (MSQ) that was originally used to evaluate motion sickness in various forms of transportation. In 1993, Kennedy et al. reported the SSQ for the first time, proposing 16 items derived from MSQ that was divided into three categories: nausea, oculomotor, and disorientation (Table 1 ) . Table 1 Symptoms in SSQ SSQ items Nausea Oculomotor Disorientation General discomfort 1 1 Fatigue 1 Headache 1 Eyestrain 1 Difficulty focusing 1 1 Increased salivation 1 Sweating 1 Nausea 1 1 Difficulty concentrating 1 1 Fullness of head 1 Blurred vision 1 1 Dizzy (eyes open) 1 Dizzy (eyes closed) 1 Vertigo 1 Stomach awareness 1 Burping 1 Total (1) (2) (3) SSQ Simulation Sickness Questionnaire Section title: Simulation Sickness Questionnaire Educational score: 3.8011224269866943 Domain: biomedical Document type: Study Language: en Formulas for scoring each component of the SSQ were proposed as Table 2 . It is possible to obtain four SSQ scores: nausea, oculomotor, disorientation, and total. The score of each category is defined as the sum of its symptom scores multiplied by a constant scaling factor. Based on a large sample of SSQ data gathered from military pilots, it is suggested that total scores can be associated with negligible (<5), minimal [ 5 – 10 ], significant [ 10 – 15 ], and concerning [ 15 – 20 ], and bad (>20) symptoms . Table 2 Computation of SSQ scores SSQ components Computation Nausea (1) × 9.54 Oculomotor (2) ×7.58 Disorientation (3) × 13.92 Total [(1) + (2) + (3)] × 3.74 SSQ Simulation Sickness Questionnaire Section title: The Procedure Educational score: 2.1633825302124023 Domain: biomedical Document type: Study Language: en Participants willingly volunteered to partake in the VR simulation scenario. Prior to the trial, they were provided with a comprehensive explanation of the sequence of the VR simulation and instructed on how to proceed during the experience. Throughout the simulation and its aftermath, participants were carefully monitored and observed for any changes in behaviour. Additionally, they were questioned regarding their experience of VRS using the SSQ instrument. Section title: The Virtual Reality Simulation-Based Training Educational score: 3.3421571254730225 Domain: biomedical Document type: Study Language: en There were two training scenarios provided within this study: the traumatic brain injury and the local anaesthetic systemic toxicity . Each participant can choose one scenario to enrol based on their preference. The traumatic brain injury (TBI) scenario consists of three settings; prehospital setting, ambulance setting, and emergency room setting. The player took role as doctor who treat the emergency patient. If the sequence is properly followed and player does not encounter problems, the TBI scenario can be completed in 20–30 min. The local anaesthetic systemic toxicity (LAST) scenario consists of 15–20 min single setting scene in the operating room. The players take role as resident doctors treating patient who experienced seizure after epidural administration. Each simulation is structured with checklists of the tasks players need to accomplish by the end of the simulation. Fig. 1 The scenario inside VR-TBI (left) and VR-LAST (right) Section title: The Virtual Reality Hardware Educational score: 1.9779833555221558 Domain: other Document type: Other Language: en In both scenarios, we employed the Oculus Quest 2 VR headset, which weighs approximately 503 g (17.7 ounces). The Occulus Quest 2 is consists of one VR headset with head-mounted display and two controllers for right and left hands . The scenarios were executed with two distinct mode options: “stationary” and “room scale”. In the room scale mode, players had the opportunity to physically walk within a designated physical area, allowing them to make real-world motions while fully immersing themselves in the virtual environment. Conversely, in the stationary mode, users were confined to a fixed 3 × 3 feet square area . Fig. 2 Virtual reality headset Fig. 3 A doctor playing inside the VR with VR headset in stationary mode Section title: Result Educational score: 3.7532784938812256 Domain: biomedical Document type: Study Language: en The study involved 75 students who participated voluntarily. Table 3 shows the baseline characteristics of participants. The majority of the participants had no prior experience with VR. During the study, several factors were observed that could influence the VRS among the participants. These factors included a history of vertigo (1.3%), myopia (34.7%), astigmatism (14.7%), wearing glasses (29.3%), and screen time. The median screen time among participants is 10 h. Additionally, another factor associated with VRS was the type of VR mode used. Among the voluntary participants, roughly equal proportions of them used room scale (52%) and stationary (48%) VR mode. There were 57.3% participants participating in TBI scenario, and the rest 42.7% participated in LAST scenario. Table 3 Baseline characteristics Characteristics Frequency (percentage)/median (Min-Max) Gender Female 37 (49.3) Male 38 (50.7) Occupation Resident 32 (42.7) General practitioner 12 (16) Medical student 31 (41.3) VR experience Never 61 (81.3) Once 9 (12) More than once 5 (6.7) Age * 27 (20–32) *Data is presents as median (min-max) Section title: Result Educational score: 2.14296555519104 Domain: biomedical Document type: Study Language: en The presence of VRS is acknowledged if the sample encounters any of the symptoms mentioned in the SSQ. There were 43 (57.3%) participants experiencing VRS in the study with total SSQ mean of 9 (SD 9.5) that is considered minimal symptoms. Figure 4 shows the frequency of symptoms from SSQ that the participants experienced. Fig. 4 Symptoms from SSQ Section title: Result Educational score: 3.284970283508301 Domain: biomedical Document type: Study Language: en Out of 75 participants, the mean score for nausea, oculomotor, disorientation, and total score is 5.97 (SD 6.4), 6.26 (SD 6.5), 125.6 (SD 132), and 9.03 (SD 9.5) respectively. The SSQ score can be classified into 5 categories based on the severity, and it is shown in Fig. 5 . Fig. 5 Sickness severity on each SSQ category Section title: Result Educational score: 4.129791259765625 Domain: biomedical Document type: Study Language: en Of the observed factors, we tried to measure the contribution of the factors to the VRS with logistic regression. The OR has been calculated as adjusted OR while controlling for one or more additional variables that could confound the results. This adjustment is done to isolate the effect of the primary variable of interest. Adjusted OR of these factors, gender, astigmatism, and VR mode are associated with VRS, as can be seen in Table 4 . Table 4 Virtual reality sickness factors Factor VRS p value Adjusted OR * (CI95%) Negative Positive Gender Female 22 15 0.028 2.82 (1.1–7.2) Male 13 25 Vertigo history No 32 42 1 - # Yes 0 2 Myopia No 25 24 0.045 2.8 (1.1–7.9) Yes 7 19 Astigmatism No 32 32 0.002 - # Yes 0 11 Wearing glasses No 26 27 0.082 2.56 (0.87–7.57) Yes 6 16 VR mode Room scale 24 15 0.001 5.6 (2.02–15.47) * Stationary 8 28 Previous VR experience Never 28 33 0.782 0.848 (0.26–2.71) At least once 7 7 Screen time (hour) 10.38 10.16 0.8 0.21 (−1.06–1.48) + *Adjusted OR from logistic regression # OR cannot be calculated due to one cell with 0 number + Mean difference (standard deviation) Section title: Discussion Educational score: 4.111189365386963 Domain: biomedical Document type: Study Language: en In this study, we observed that virtual reality sickness (VRS) affected 57.3% of the 75 participants . This number aligns with findings from previous studies, which reported an incidence rate between 60 and 70% [ 13 , 18 – 21 ]. The mean SSQ score in our study was 9 with a range of 0 to 29, indicating lower score than previous study by Saredakis et al. which reported a pooled mean of 28 with a range of 14.30 to 35.27 . Among the SSQ components, disorientation scored the highest at 125.6, followed by oculomotor at 6.36, and nausea at 5.97 . These results are consistent with previous research reporting pooled mean SSQ scores of 16.72, 17.09, and 23.5 for nausea, oculomotor, and disorientation, respectively . According to Kenendy et al., total SSQ score of 9 indicates minimal symptoms . Although majority of the participants in our study experienced negligible to significant symptoms, there were 16% of them that experienced severe symptoms, and further mitigation plan should be prompted. Section title: Discussion Educational score: 4.027458667755127 Domain: biomedical Document type: Other Language: en In the context of emergency setting simulations, healthcare professionals are mandated to possess not just the knowledge base, but a comprehensive technical skill set. This proficiency encompasses the continuous monitoring of hemodynamic changes subsequent to specific medical procedures like looking at the monitor over and over after performing a medical procedure. This well involved repetitive rotational movement of the neck. Other technical skill healthcare professionals need to understand are the assembly and operation of medical equipment, effective communication, and a diverse array of medical competencies, such as airway management, resuscitation, and the precise administration of pharmaceuticals. In an emergency scenario, temporal considerations are of paramount importance, as any delays in response time or decision-making may yield profound and potentially life-altering consequences. Moreover, the demanding nature of emergency setting simulations, characterized by intricate and occasionally repetitive actions, can engender VRS. Section title: Discussion Educational score: 4.110373497009277 Domain: biomedical Document type: Study Language: en The disorientation component of the SSQ, encompassing symptoms such as difficulty focusing, nausea, fullness of the head, blurred vision, dizziness with eyes open or closed, and vertigo, exhibited a high occurrence of bad scores (>20) in 43 participants (57.3%) as seen in Fig. 5 . Our research findings have illuminated that VRS, particularly of a severe degree, predominantly falls within the disorientation category. This observation implies that the performance of users engaged in simulation exercises may be disrupted and hindered, preventing them from effectively showcasing their genuine competencies during training simulations. This can further impact learning process. Kelly et al. discovered that virtual reality users are particularly susceptible to disorientation, especially when using locomotion interfaces lacking self-motion cues. To address this issue, incorporating environmental cues, such as boundaries, into the design of locomotion interfaces is crucial to reduce disorientation-related effects . Section title: Discussion Educational score: 4.108233451843262 Domain: biomedical Document type: Study Language: en Our study found that hardware-related issues, specifically the VR mode, were associated with VRS. Participants using the stationary mode were five times more likely to experience VRS. This is in line with previous research indicating that nonstationary VR modes, especially physically walking mode, can help reduce the incidence of VR sickness . Chang et al. classified VRS factors into three domains: hardware, content, and human factors. Hardware factors encompassed various VR device manipulations, including display type, display mode, time delay, and device weight. Content factors involved altering VR scenes or scenarios, such as graphics, task-related features, duration, and controllability. Human factors considered individual differences, such as age, gender, BMI, postural sway, previous VR experience, and eye-related measures like interpupillary distance, refractive error, and eye-hand coordination . In Saredakis et al.’s study, the mean SSQ scores for nausea, oculomotor, and disorientation were 22.6, 22.4, and 28.5, respectively, in the stationary group, whereas in the walking group, they were 13.2, 15.3, and 18.5, respectively . Section title: Discussion Educational score: 4.073320388793945 Domain: biomedical Document type: Study Language: en Our findings revealed that male are more prone to VRS. This is the opposite of previous studies. Schmitz et al. found gender as an essential variable associated with motion sickness in VR systems . Males were 2.8 times more likely to experience VRS than females. However, a large-scale meta-analysis reported no significant gender difference in VRS . Former VR experience was believed to increase the likelihood of VRS . Surprisingly, our study did not find any significant effect of previous VR experience on VRS. Further research is needed to fully comprehend the underlying pathophysiology of this phenomenon . Young et al. discovered that ocular refraction disorders influenced motion sickness during head-mounted display experiences. Myopic and astigmatic participants showed significantly higher SSQ scores for nausea and disorientation. Our findings are aligned with these results, as we observed a higher incidence of VRS in participants with myopia and astigmatism. Section title: Discussion Educational score: 4.067232131958008 Domain: biomedical Document type: Study Language: en This study has several limitations. Firstly, its cross-sectional design makes it difficult to establish causal relationships between factors. It would be better if further research could address the dose-response relationship between the amount of time spent in VR-based learning and development of fatigue. Conducting further research using cohort or randomized trials would be more suitable for addressing this issue. Secondly, the consecutive sampling method used may introduce bias as it is a nonprobability sampling technique. Thirdly, the lack of pre-treatment SSQ scores before participants engaged in the VR experience could lead to additional biases in interpreting the results. Section title: Discussion Educational score: 1.6522172689437866 Domain: other Document type: Study Language: en We interviewed participants with simple preference questions, asking their opinion whether VR is potential for learning method in the near future and whether the VRS that they experienced hinder them for trying VR for educational purposes in the near future. All of the 75 people answered that VR has the potential for learning method, and only one of 75 people has chosen to avoid using VR in the near future due to the side effect that he experienced. Section title: Discussion Educational score: 3.299225330352783 Domain: biomedical Document type: Other Language: en Based on the current report, we recommend using the room-scale mode as the locomotion interface for VR to minimize VRS. Additionally, participants with refractive disorders should receive proper treatment by wearing glasses for refractive correction before engaging in VR activities. These strategies are essential to ensure all participants have the best possible environment to enhance learning outcomes in VR-based simulation training for traumatic brain injury management. Section title: Conclusion Educational score: 3.2116148471832275 Domain: biomedical Document type: Study Language: en The incidence of virtual reality sickness was associated with male gender, myopia, astigmatism, and the use of stationary VR mode. To prevent virtual reality sickness during VR simulation training, it is essential to engage in VR activities in room-scale or walking mode and ensure appropriate correction of any refractive disorders. Future research should address the dose-response relationship between the amount of time spent in VR-based learning and development of virtual reality sickness. | Study | biomedical | en | 0.999997 |
PMC11699197 | Section title: Introduction Educational score: 3.825775384902954 Domain: biomedical Document type: Review Language: en The integration of digital health tools into healthcare has transformed how individuals manage their health, providing opportunities for improved quality of life (QoL) and psychological adjustment. These tools encompass mobile health applications, wearable devices, and telemedicine platforms that enable users to monitor health metrics, access personalized feedback, and engage in health-promoting behaviors . While much of the focus has been on managing chronic conditions such as diabetes and hypertension , there is increasing recognition of their potential to address the unique challenges faced by specific populations, including long-term blood donors. Section title: Introduction Educational score: 3.907191514968872 Domain: biomedical Document type: Study Language: en Blood donation, a critical public health activity, relies heavily on the sustained contributions of long-term donors. Long-term blood donors, defined in this study as individuals who donate blood at least twice per year for a minimum of three years, play a crucial role in maintaining a stable and reliable blood supply. These donors are often highly committed to the practice, driven by altruism and a sense of social responsibility. However, these individuals often face both physical challenges, such as fatigue, iron depletion, and dizziness , and psychological concerns, including stress, anxiety, and societal perceptions about repeated donations . These challenges can disrupt social relationships, impact emotional well-being, and ultimately affect donors' long-term commitment . Section title: Introduction Educational score: 3.886024236679077 Domain: biomedical Document type: Study Language: en Within Saudi Arabia, maintaining a stable blood supply is essential, yet achieving this goal is complicated by a geographically dispersed population, varying health literacy levels, and cultural perceptions around blood donation . Digital health tools offer a promising avenue for addressing these issues by improving donor engagement, providing health monitoring, and supporting psychological well-being. While studies have highlighted the benefits of digital platforms in healthcare, there is a lack of localized research exploring their application among Saudi blood donors. This study aims to fill this gap by examining how digital health tools can improve both the QoL and psychological adjustment of long-term donors in Saudi Arabia, emphasizing the cultural and healthcare system context. Section title: Introduction Educational score: 1.3843321800231934 Domain: biomedical Document type: Other Language: en Background Section title: Introduction Educational score: 3.852778434753418 Domain: biomedical Document type: Review Language: en Research demonstrates the effectiveness of digital health tools in managing chronic health conditions. For example, Debon et al. showed that mobile applications for individuals with hypertension enhanced their ability to monitor blood pressure and make informed decisions, contributing to improved QoL . Similarly, wearable devices tracking physical activity, heart rate, and sleep patterns have been linked to better disease management and psychological outcomes in individuals with chronic conditions . These tools enable real-time monitoring, personalized feedback, and tailored interventions, making healthcare more accessible and proactive. Section title: Introduction Educational score: 3.8907744884490967 Domain: biomedical Document type: Review Language: en In contrast, research on the use of digital health tools specifically for blood donors remains limited. Although some parallels exist between the needs of long-term donors and individuals with chronic conditions such as the necessity for ongoing health monitoring and strategies for psychological support, the challenges faced by donors are unique . Psychological stressors, including anxiety about health risks and societal stigmas, can discourage continued participation in blood donation programs . Long-term donors must navigate these barriers to sustain their commitment, which makes targeted interventions essential . Studies have acknowledged the potential role of digital tools in supporting blood donors. For instance, gamified mobile applications have been used to educate donors, improve physical health outcomes, and foster engagement . Telemedicine platforms offering remote consultations have provided continuous support, enhancing adherence to donation schedules and overall well-being . However, these efforts predominantly focus on physical health and do not adequately address psychological adjustment or QoL, particularly within specific cultural contexts. Section title: Introduction Educational score: 2.0683584213256836 Domain: biomedical Document type: Other Language: en In Saudi Arabia, where cultural and systemic factors significantly influence blood donation practices, localized research is crucial. The unique societal perceptions, coupled with the rapid modernization of the healthcare system, present an opportunity to explore tailored solutions. By leveraging digital health tools, there is potential to address the psychological and physical challenges faced by long-term blood donors while simultaneously promoting health literacy and engagement. Section title: Introduction Educational score: 1.7577321529388428 Domain: biomedical Document type: Other Language: en Objectives Section title: Introduction Educational score: 3.7719714641571045 Domain: biomedical Document type: Study Language: en This study aims to investigate the impact of digital health tools in enhancing the QoL and psychological adjustment of long-term blood donors in Saudi Arabia. The research will focus on the development and application of culturally relevant digital interventions, assessing their effectiveness in mitigating physical and emotional challenges and supporting sustained donor participation. Section title: Materials and methods Educational score: 1.6726114749908447 Domain: biomedical Document type: Study Language: en Study settings and participants Section title: Materials and methods Educational score: 3.993352174758911 Domain: biomedical Document type: Study Language: en An online cross-sectional survey design was adopted in this study conducted in Saudi Arabia, targeting long-term blood donors who have participated in at least 10 donation events over the past five years at blood banks and healthcare facilities. The study encompassed both urban and rural settings to capture the variability in access to healthcare and digital tools, as well as differing cultural attitudes toward blood donation. Participants were selected from key regions, including Riyadh, Jeddah, and the Eastern Province, representing diverse socioeconomic backgrounds, levels of health literacy, and technological adoption. This approach ensured the representation of donors with varying experiences in terms of healthcare access, physical and psychological challenges, and their use of digital health tools, thereby providing a comprehensive understanding of the long-term blood donor population in Saudi Arabia. Section title: Materials and methods Educational score: 3.5505006313323975 Domain: biomedical Document type: Study Language: en The inclusion criteria for participants were: individuals aged 18-60 years, who have been regular blood donors (donating at least twice per year) for at least 3 years, and who voluntarily agreed to participate in the study. The age range of 18-60 years was selected to align with international blood donation guidelines, which typically recommend eligibility between these ages for ensuring donor safety and adequate physical capacity for donation . Additionally, this range encompasses the majority of active donors, as older populations often face age-related health issues that may limit donation frequency . Section title: Materials and methods Educational score: 2.534691095352173 Domain: biomedical Document type: Study Language: en The requirement of at least three years of regular blood donation was set to ensure that participants had sufficient experience as long-term donors, allowing the study to focus on those who are familiar with the physical and psychological impacts of repeated donations. Prior research highlights that donors with over three years of consistent participation are more likely to experience long-term effects and have established donation habits . Section title: Materials and methods Educational score: 3.509488344192505 Domain: biomedical Document type: Study Language: en Exclusion criteria included individuals with physical or mental health conditions that could interfere with their ability to complete the survey or participate in the digital health tools usage assessment. This exclusion was based on ethical considerations to avoid placing additional burdens on individuals whose health conditions might limit their ability to engage with the study interventions or skew results due to unrelated health factors. Similar studies on digital health tools emphasize the importance of excluding individuals with confounding health conditions to maintain study validity and participant safety . Section title: Materials and methods Educational score: 1.3552314043045044 Domain: biomedical Document type: Other Language: en Sampling and recruitment Section title: Materials and methods Educational score: 4.07424783706665 Domain: biomedical Document type: Study Language: en The sampling strategy employed in this study was purposive , aiming to recruit long-term blood donors with extensive blood donation experience, defined as individuals who have donated regularly for at least three years. Purposive sampling was chosen due to the need to focus on a specific subgroup of blood donors who could provide in-depth insights into the physical, psychological, and behavioral aspects of long-term blood donation. This approach allows researchers to ensure that the participants align closely with the study’s objectives, which require experience with repeated donation and potential interactions with digital health tools. While purposive sampling has the potential to introduce selection bias, it is particularly suitable for exploratory research where the goal is to generate insights from a targeted population rather than to achieve statistical generalizability . By selecting participants across diverse demographics, including age, gender, and geographic location (urban and rural regions within Saudi Arabia), the study aimed to mitigate this limitation and ensure the representation of a wide range of donor experiences. This approach is supported by previous studies in healthcare research, where purposive sampling has been successfully employed to explore the nuanced experiences of specific populations . Section title: Materials and methods Educational score: 3.509894371032715 Domain: biomedical Document type: Study Language: en Participants were selected from blood donation centers in key urban and rural areas, ensuring the sample's diversity and representativeness. Recruitment took place in collaboration with local hospitals, blood banks, and healthcare providers, who assisted in reaching potential participants. Additionally, healthcare professionals at the donation centers provided verbal invitations to eligible donors during their routine visits. Interested individuals were then directed to the study's online platform or to on-site recruitment staff for further details about participation. The target sample size is approximately 500 participants (based on an estimated sample of 383 calculated using Cochran’s formula ), distributed proportionally across the selected regions. This sample size is designed to provide sufficient statistical power for analyzing variations in public perceptions, behaviors, and attitudes toward air quality and respiratory health across different demographic and environmental contexts in Saudi Arabia. Section title: Materials and methods Educational score: 1.9014811515808105 Domain: biomedical Document type: Study Language: en A total of 523 participants were included in the study; however, 25 participants did not complete the full survey, leading to a final sample of 498 participants. Section title: Materials and methods Educational score: 1.015099287033081 Domain: biomedical Document type: Other Language: de Instruments Section title: Materials and methods Educational score: 4.118406295776367 Domain: biomedical Document type: Study Language: en To measure the quality of life and psychological adjustment of the participants, two validated instruments were employed: the WHO Quality of Life-Brief Version (WHOQOL-BREF) and the Coping Orientation to Problems Experienced Inventory (Brief-COPE) inventory . WHOQOL-BREF is a widely recognized instrument developed by the WHO to assess the QoL across multiple dimensions. It consists of 26 items that measure four domains: physical health, psychological well-being, social relationships, and environmental factors. The WHOQOL-BREF is particularly suitable for this study as it provides a comprehensive evaluation of how digital health tools may impact various aspects of the participants’ lives, from their physical health and psychological state to their social interactions and environmental satisfaction. Questions are rated on a five-point Likert scale, with higher scores indicating better quality of life. This instrument's broad scope makes it ideal for capturing the multifaceted effects of digital health tools on long-term blood donors. The Brief COPE scale is a validated tool used to assess how individuals cope with stress and challenges in their lives. It is a shortened version of the COPE inventory and includes 28 items that measure 14 different coping strategies, such as active coping, planning, positive reframing, and seeking social support. The Brief COPE is particularly relevant for this study as it allows researchers to evaluate the coping mechanisms employed by long-term blood donors when managing the psychological demands associated with regular blood donation. By analyzing the use of digital health tools in relation to these coping strategies, the study aims to determine whether these tools facilitate more effective coping and contribute to better psychological adjustment. Section title: Materials and methods Educational score: 4.039675712585449 Domain: biomedical Document type: Study Language: en These tools were adapted to suit the cultural and linguistic context of Saudi Arabia. The adaptation process included translation into Arabic using a forward-translation and back-translation method to ensure semantic equivalence, as recommended for cross-cultural research . Additionally, a panel of bilingual experts in psychology and public health reviewed the scale for cultural relevance and clarity, making adjustments to items that may not align with local norms or experiences. For example, coping strategies involving social support were contextualized to reflect the importance of family and community in Saudi culture. A pilot test was conducted with a small sample of Saudi blood donors (n = 30) to assess the tool's reliability and validity in the target population. The data collected from this pilot study were analyzed, and Cronbach's alpha coefficient for all items was calculated. The coefficient exceeded 0.7, indicating robust internal consistency and reliability of the questionnaire . Feedback from the pilot study was used to refine the language and ensure the scale accurately captured the coping mechanisms relevant to this group. Section title: Materials and methods Educational score: 1.0735617876052856 Domain: biomedical Document type: Other Language: it Data collection Section title: Materials and methods Educational score: 2.184095621109009 Domain: biomedical Document type: Study Language: en Data for this study were collected over four weeks using a structured survey questionnaire, available in both English and Arabic. The questionnaire was distributed exclusively through online platforms to ensure broad accessibility and convenience for participants across various regions in Saudi Arabia, including urban, suburban, and rural areas. The online distribution leveraged social media, email networks, and community forums to reach a diverse population. This digital approach facilitated the collection of comprehensive data on public perceptions and practices related to air quality and respiratory health while ensuring participants could complete the survey at their convenience. Section title: Materials and methods Educational score: 0.9184456467628479 Domain: biomedical Document type: Other Language: tl Data analysis Section title: Materials and methods Educational score: 2.6906380653381348 Domain: biomedical Document type: Study Language: en To achieve the study's objectives, the data were analyzed using the IBM SPSS Statistics for Windows, Version 24.0 . Descriptive statistics, including means and standard deviations, were employed to present the demographic characteristics of the participants. Additionally, a two-sample t-test with unequal variances and a one-way ANOVA were conducted to analyze the data further. Section title: Materials and methods Educational score: 1.149239420890808 Domain: other Document type: Other Language: en Ethical considerations Section title: Materials and methods Educational score: 1.9612789154052734 Domain: biomedical Document type: Study Language: en The study received approval from the Research Ethics Committee at Imam Abdulrahman Bin Faisal University . Informed consent was obtained from all participants prior to their involvement, with clear explanations provided regarding the study's purpose, procedures, and potential risks. To address concerns about discomfort with sensitive survey questions, participants were informed of their right to skip any question or withdraw from the study at any time without any repercussions. Additionally, the survey design avoided intrusive or overly personal questions, focusing instead on general coping mechanisms, digital health tool usage, and overall well-being. Section title: Materials and methods Educational score: 2.4344475269317627 Domain: biomedical Document type: Study Language: en To ensure robust confidentiality and data security, anonymization was carried out through the removal of all directly identifiable data such as names, contact information, and IP addresses from the dataset prior to analysis. A unique alphanumeric code was assigned to each participant to enable data tracking while preserving anonymity. Data were securely stored on encrypted servers accessible only to authorized research personnel. Furthermore, the study adhered to ethical guidelines for research involving digital health tools, ensuring that privacy concerns related to these tools were clearly addressed in the consent process. Section title: Materials and methods Educational score: 2.079741954803467 Domain: biomedical Document type: Study Language: en By implementing these measures, the study prioritized participant safety, confidentiality, and trust, aligning with ethical research standards while minimizing potential risks associated with privacy or sensitive questions. Section title: Results Educational score: 3.602346897125244 Domain: biomedical Document type: Study Language: en A total of 523 participants were included in the study; however, 25 participants did not complete the full survey, leading to a final sample of 498 participants. As shown in Table 1 , the demographic data revealed a balanced gender distribution among participants, with a slight predominance of females (50.8%) over males (49.2%). The age distribution highlighted a younger sample, with 34.7% of participants aged 18-30, followed by 22.5% in the 31-40 age group. Middle-aged groups (41-50 years and 51-60 years) represented a combined 34.2% of the sample, while only 8.6% of participants were over 60, suggesting that the findings might be more relevant for younger and middle-aged demographics. Education levels showed diverse representation: participants with a diploma were the largest group (27.3%), followed by those with primary or secondary education (20.7%). Bachelor's degree holders constituted 20.3%, while those with a Master’s degree or higher represented 17.1%, and uneducated participants made up 14.7%. This range across educational levels may have contributed to varied perspectives within the sample, supporting generalizability across different educational backgrounds. Section title: Results Educational score: 4.024355888366699 Domain: biomedical Document type: Study Language: en Table 2 provides an overview of participants' perceptions regarding the impact of digital health tools on their QoL and psychological adjustment. Across all factors, the mean scores generally hovered around 3.25-3.36, suggesting a moderate to positive perception of these tools. Self-distraction and denial received the highest mean scores ± SD (3.36 ± 0.97 and 3.33 ± 0.98, respectively), indicating that participants perceive these tools as particularly helpful in managing stress or emotional challenges. On the other hand, substance use and venting had the lowest mean scores (3.21 and 3.24, respectively), suggesting that while digital health tools were still perceived positively, they may have less of an impact on managing these specific behaviors. Active coping and positive reframing scored relatively high as well, suggesting that participants viewed digital tools as useful in fostering adaptive coping strategies. Section title: Results Educational score: 4.0055036544799805 Domain: biomedical Document type: Study Language: en Regarding psychological adjustment, participants rated physical health and psychological well-being highly (3.30 ± 1.04 and 3.31 ± 0.95, respectively), signifying the positive role of digital health tools in improving overall health and mental well-being. Social relationships and environmental factors were also perceived positively, with mean scores of 3.27 ± 0.88 and 3.29 ± 0.80, respectively, indicating that participants felt these tools support not only individual well-being but also social and environmental contexts. Overall, the data suggests a broadly favorable perception of digital health tools in enhancing both quality of life and psychological adjustment, with some factors, such as denial and self-distraction, standing out as particularly beneficial. Section title: Results Educational score: 4.082479476928711 Domain: biomedical Document type: Study Language: en The one-way ANOVA of the data (Table 3 ) revealed meaningful insights into how long-term blood donors' perceptions of digital health tools vary across different age groups. The significant differences observed suggest that older participants tend to perceive digital health tools as more beneficial for their psychological adjustment and QoL compared to younger donors. This may be attributed to a variety of factors, such as the greater experience and possibly more pronounced health concerns among older individuals, which could make them more receptive to health interventions. Conversely, younger blood donors may have different health-related priorities or expectations, potentially explaining their lower ratings across most variables. Section title: Results Educational score: 4.0984296798706055 Domain: biomedical Document type: Study Language: en The one-way ANOVA of the data (Table 4 ) highlighted notable trends regarding the impact of educational attainment on long-term blood donors' perceptions of digital health tools in enhancing their QoL and psychological adjustment. Statistically significant differences were observed across various educational groups, with participants possessing higher levels of education consistently reporting more favorable perceptions. For instance, those with a Bachelor’s degree or higher demonstrated higher mean scores in most factors, such as active coping, use of emotional support, self-blame, physical health, and psychological well-being, suggesting a stronger positive response to digital health tools compared to those with lower educational levels. In contrast, participants with lower levels of education, such as uneducated or with primary/secondary education, tended to report the lowest scores across the majority of measures. Section title: Results Educational score: 4.017520904541016 Domain: biomedical Document type: Study Language: en The t-test results (Table 5 ) revealed significant gender-based differences in the perceptions of long-term blood donors regarding the impact of digital health tools on their QoL and psychological adjustment. Across all factors, female individuals reported consistently higher mean scores compared to males, indicating that women perceive digital health tools as more beneficial in enhancing their QoL and psychological well-being. For example, women scored notably higher in factors like active coping, denial, substance use, use of emotional support, and self-blame, reflecting a more positive engagement with these tools. Section title: Discussion Educational score: 3.983191728591919 Domain: biomedical Document type: Study Language: en The results of this study reveal a generally positive perception among long-term blood donors in Saudi Arabia regarding the impact of digital health tools on their QoL and psychological adjustment. These findings align with previous research, which indicates that digital health tools such as mobile apps, wearable devices, and telemedicine can enhance users' well-being and provide vital support for chronic health management . Specifically, our findings show that participants value these tools for stress management, health monitoring, and emotional support, similar to what other studies have observed in chronic disease management contexts . The objective of this study, which was to investigate the impact of digital health tools in enhancing the QoL and psychological adjustment of long-term blood donors in Saudi Arabia, was assessed from different contexts. Section title: Discussion Educational score: 4.103630542755127 Domain: biomedical Document type: Study Language: en Age-based differences in perceptions emerged, with older participants perceiving digital health tools as more beneficial than younger donors. This result could be linked to a greater reliance on health support and a heightened awareness of health-related issues in older populations, as observed in the literature . Furthermore, younger blood donors may have different expectations from digital health tools, potentially finding them less useful for their specific needs. This finding suggests the need for age-tailored digital health interventions to maximize engagement and relevance across age groups, an approach recommended by similar studies addressing chronic health conditions . Tailoring these tools to better suit the needs and preferences of younger blood donors might help bridge the gap and increase the overall effectiveness of digital health interventions. Furthermore, the significant statistical differences underscored the importance of considering age as a key factor in designing and evaluating digital health solutions, as the response to such tools may not be uniform across different demographic groups. This could inform future strategies for improving the psychological well-being and coping mechanisms of long-term blood donors through targeted digital health initiatives. Section title: Discussion Educational score: 4.040122032165527 Domain: biomedical Document type: Study Language: en Gender differences in the perception of digital health tools were also observed, with female participants consistently reporting higher perceived benefits in terms of emotional and psychological support. This aligns with prior research showing that women may be more likely to engage with health management tools for emotional support and stress management than men . This highlights the importance of gender-sensitive design in digital health tools, potentially increasing their appeal and impact by addressing specific user needs more effectively. Although digital health tools are often perceived as universally beneficial, our findings suggest that factors such as age, gender, and educational background significantly influence user perceptions and experiences. This aligns with the study by Al-Hajri et al., which emphasized the need for culturally and demographically relevant adaptations of digital health tools for diverse populations . Section title: Discussion Educational score: 4.076958656311035 Domain: biomedical Document type: Study Language: en In the present study, the gender gap was particularly pronounced in self-distraction, behavioral disengagement, venting, and humor, with females again reporting higher mean scores, suggesting that women may experience greater emotional benefits or engagement with coping mechanisms facilitated by digital health interventions. On the other hand, male individuals tended to score lower on these factors, which could indicate differences in coping styles or willingness to use digital tools for emotional support. The results suggest that gender may influence how digital health tools are perceived and utilized, with women perhaps benefiting more in terms of emotional support and psychological adjustment. This could imply that digital health tools need to be adapted or tailored to account for these gender differences, potentially offering more targeted interventions for males to increase engagement and psychological benefit. Section title: Discussion Educational score: 4.091294288635254 Domain: biomedical Document type: Study Language: en Educational differences further underscore the need for tailored interventions. Participants with higher educational levels reported greater benefits from digital health tools, perhaps reflecting better digital literacy and health awareness, as has been suggested in previous studies on health tool usability . Participants with lower education levels might face barriers related to technology use or may be less aware of potential benefits, emphasizing the importance of user-friendly design and accessible health information for all educational levels. The findings from the present study suggest that education may play a significant role in how individuals perceive and utilize digital health interventions, possibly due to differences in digital literacy, health awareness, or the ability to engage with more complex health-related information. For example, those with a Master’s degree or higher consistently showed the highest mean scores in self-blame, substance use, and venting, which may reflect a better understanding of psychological health and coping mechanisms. Section title: Discussion Educational score: 3.944713592529297 Domain: biomedical Document type: Study Language: en The study also highlights the limitations of current digital health tools in addressing the specific psychological needs of long-term blood donors. While tools for general stress management were beneficial, aspects such as substance use and behavioral disengagement were perceived as less impacted. This finding reflects gaps identified in the reviews by López et al. and Lattie et al. , which noted that many existing digital tools inadequately address complex psychological needs or fail to provide personalized interventions for specific behavioral challenges. Addressing this gap could involve incorporating evidence-based psychological strategies within digital platforms, such as cognitive-behavioral components or motivational modules tailored to donor-specific stressors. Section title: Discussion Educational score: 1.4543850421905518 Domain: biomedical Document type: Other Language: en Study limitations and future work Section title: Discussion Educational score: 4.083634376525879 Domain: biomedical Document type: Study Language: en This study has several limitations. First, the cross-sectional design restricts causal inferences regarding the impact of digital health tools on long-term blood donors' QoL and psychological adjustment. Additionally, reliance on self-reported data may introduce response bias, as participants' perceptions might not fully reflect the objective impact of these tools. The focus on Saudi Arabia limits the generalizability of the findings, as cultural factors, such as attitudes toward health technology and gender dynamics in healthcare usage, may have influenced participants' experiences. Moreover, the non-random purposive sampling limits generalizability. Future research should consider using a random sample and include diverse populations to enhance external validity. Longitudinal studies are needed to establish causal relationships, and further exploration of specific digital features and culturally tailored interventions could provide more targeted insights for improving donor retention and well-being. Section title: Discussion Educational score: 0.8941543698310852 Domain: other Document type: Other Language: en Implications Section title: Discussion Educational score: 4.090012550354004 Domain: biomedical Document type: Study Language: en The findings of this study contribute to the theoretical understanding of digital health’s role in enhancing QoL and psychological adjustment, extending previous research primarily focused on chronic disease management to the unique context of long-term blood donors. The results underscore the need to consider demographic factors such as age, gender, and education level in digital health research, as these factors significantly influence user engagement and perception of benefits. Practically, these insights suggest that healthcare providers and developers should prioritize the customization of digital health tools to better meet the diverse needs of long-term donors. Tailoring these tools to address specific psychological stressors, coping mechanisms, and cultural considerations can potentially improve user experience, engagement, and donor retention, supporting a more resilient and sustainable blood donation system. Section title: Conclusions Educational score: 4.047977447509766 Domain: biomedical Document type: Study Language: en This study underscores the positive role of digital health tools in enhancing the QoL and psychological adjustment of long-term blood donors in Saudi Arabia. Findings indicate that these tools are perceived as beneficial for managing physical and psychological challenges, especially among older and more educated donors, highlighting the influence of demographic factors on engagement. The findings of the study indicate that digital tools can play a significant role in facilitating coping mechanisms, promoting emotional well-being, and encouraging donor retention. However, it is important to exercise caution in making causal claims due to the cross-sectional design, which limits the ability to establish temporal relationships. Section title: Conclusions Educational score: 3.9852938652038574 Domain: biomedical Document type: Study Language: en While the data provide evidence for the effectiveness of digital health tools, areas such as the role of substance use and behavioral disengagement in coping strategies require further exploration. These factors may influence how donors engage with digital tools and should be studied in greater depth to understand their impact fully. Similarly, the influence of demographic variables such as age, gender, and socioeconomic status on the use and effectiveness of digital health tools was not exhaustively analyzed, leaving room for further investigation. Future research should focus on these dimensions to strengthen the link between the study’s results and its conclusions. Longitudinal studies examining the interplay between coping mechanisms, digital engagement, and demographic factors could provide more robust insights, allowing for tailored interventions to optimize the benefits of digital health tools for diverse donor populations. | Review | biomedical | en | 0.999997 |
PMC11699205 | Section title: Contributors Educational score: 0.9213530421257019 Domain: other Document type: Other Language: en DK literature search, data collection, data analysis, methodology, KK-literature search, data collection, data analysis, methodology, JK–literature search, data collection, data analysis, methodology, KG-data collection, EB–data collection, KN–data collection, writing original draft, RS–data collection, study conceptualization, ZNZ–writing review and editing, data curation, methodology, WF–study conceptualization, data curation, methodology, writing review and editing. Section title: Editor note Educational score: 1.0257840156555176 Domain: other Document type: Other Language: en The Lancet Group takes a neutral position with respect to territorial claims in published maps and institutional affiliations. Section title: Declaration of interests Educational score: 0.9640229940414429 Domain: other Document type: Other Language: en None of the Authors have any conflict of interest to disclose. | Other | other | en | 0.999997 |
PMC11699213 | Section title: Introduction Educational score: 2.541626214981079 Domain: biomedical Document type: Other Language: en Malignant neoplasm of the breast was the fifth leading cause of death among women in Germany in 2020, with 18,500 deaths, according to the last available statistics of the German Federal Statistical Office . Socioeconomic inequalities in mortality due to breast cancer (BC) have been documented in Germany both at the individual and district level , where low-income women or women living in areas with higher levels of deprivation entail a higher mortality risk. Section title: Introduction Educational score: 2.1106770038604736 Domain: biomedical Document type: Other Language: en The European Commission encouraged Member States to implement organised screening programmes (OSP) in 2003, with invitations being sent out on a biannual basis to women aged between 50 and 69 . Since then, numerous European studies have reported a decrease in breast cancer mortality rates and a reduction in inequalities in access to screening services . Section title: Introduction Educational score: 1.866197943687439 Domain: biomedical Document type: Study Language: en Germany initiated the implementation of the OSP in 2005 and achieved full implementation by 2009 . The participation rate following an invitation has fluctuated between 43% and 55% over the past two decades, failing to reach the 70% benchmark recommended by the European Commission . Additionally, in 2020, 10.38% of the targeted women reported that they had never attended BCS in their lifetime . Section title: Introduction Educational score: 3.870729923248291 Domain: biomedical Document type: Review Language: en Several studies have investigated the sociodemographic characteristics of women who are at higher risk of not participating in breast cancer screening (BCS) programmes. In the most recent international systematic review, Mottram et al. observed that migrant women, women with lower socioeconomic status, without home ownership, and those who experienced false positives had the lowest attendance rates . In a scoping review of the German context, Pedrós Barnils et al. identified native women, women with lower incomes, women living in rural areas, and those not cohabiting with their partners as those with the lowest lifetime BCS attendance rates. However, the author also highlighted considerable heterogeneity in methods and, therefore, results . Section title: Introduction Educational score: 3.6403651237487793 Domain: biomedical Document type: Study Language: en Usually, inequalities in attendance are documented based on independent social dimensions. To explore correlations between social dimensions and BCS attendance, most studies incorporate variables deemed relevant (i.e. based on specific assumptions) into statistical models and then, in multivariate analyses, estimate the independent effect of each social dimension with the effects of other covariates held constant. However, as no individual can be defined by a single social dimension alone , it is unlikely that examining the independent effect of each social dimension will provide a comprehensive understanding of the inequalities in accessing cancer screenings. Section title: Introduction Educational score: 2.886972188949585 Domain: other Document type: Other Language: en Instead, individuals sit at the intersection of different social dimensions, and this needs to be considered when assessing who is at higher risk of not attending BCS. Methodologically and conceptually, the way the risk for not attending BCS of a person with a migration background and low educational attainment can be seen differently: either as the sum of (presumably) independent discrimination dimensions or as accounting for the discrimination of being a migrant from a lower social class simultaneously . It is, therefore, essential to employ a framework that allows to detect the inherent complexity of inequalities when attempting to understand the underlying factors influencing BCS attendance. The most appropriate approach is to adopt the framework of intersectionality . Intersectionality theory, as first proposed by law scholar Kimberlé Crenshaw in 1989, posits that the experiences of discrimination (e.g. classism, racism) based on disadvantaged social positions (e.g. low social class, migration background) overlap and derive into unique experiences of discrimination . Section title: Introduction Educational score: 3.663999557495117 Domain: biomedical Document type: Review Language: en Over the past two decades, in the field of population health, quantitative intersectionality has given rise to new methodological approaches. The most commonly used methods for describing intersectional inequalities within a population range from simple cross-classification descriptions or regressions to methods that account for discriminatory accuracy (e.g. analysis of individual heterogeneity and discriminatory accuracy (AIHDA) and multilevel analysis of individual heterogeneity and discriminatory accuracy (MAIHDA)) or are data-driven (e.g. decision trees) . Section title: Introduction Educational score: 3.655245780944824 Domain: biomedical Document type: Study Language: en To build cross-classification regression and AIHDA or MAIHDA, the (potentially) relevant social dimensions are usually selected on the basis of the available evidence, and these dimensions are combined to identify intersectional subgroups. This is a deductive approach. In contrast, decision trees and analogous heuristic procedures employ an inductive methodology to identify which variables are most predictive of an outcome assuming non-linear relationships between the variables . This enables a data-driven determination of the social dimensions that will constitute intersectional subgroups, often previously unnoticed . Decision trees have been applied as statistical exploratory tools for classification in population health . Section title: Introduction Educational score: 3.846583127975464 Domain: biomedical Document type: Study Language: en To the author's knowledge, no explicit comparisons between these approaches to identify intersectional inequalities in breast cancer screening have been conducted; besides, no study has employed an intersectional approach for reporting inequalities in breast cancer screening in Germany. Consequently, the present study aims to identify intersectional groups of women aged 50–69 who are at higher risk of never attending BCS in Germany comparing two analytical strategies: a) evidence-informed regression and b) decision tree-based regression. Section title: European Health Interview Survey Educational score: 2.125779628753662 Domain: biomedical Document type: Study Language: en For this analysis, we employed cross-sectional data from the European Health Interview Survey (EHIS) third wave conducted in Germany in 2019. The survey sample size was 23,001 respondents, corresponding to 21.6% of the invited participants . EHIS is conducted every 5 years and focuses on individuals aged 15 and above residing in private households . Section title: Primary outcome Educational score: 3.365307569503784 Domain: biomedical Document type: Study Language: en The primary outcome of this study was self-reported breast cancer screening attendance via mammography at least once in a lifetime for women aged 50–69 in Germany. Responses were dichotomised, excluding those who indicated “unknown” or left the question unanswered to prevent uncertainty about whether the respondent reported never attending BCS (no = 0, yes = 1). Section title: Explanatory variables Educational score: 2.162663221359253 Domain: biomedical Document type: Study Language: en The explanatory variables to predict BCS derive from the PROGRESS-Plus characteristics: place of residence, race, ethnicity, culture and language, occupation, sex, education, socioeconomic status, social capital and plus (i.e. other potentially discriminatory factors) . These variables have been widely used to disentangle social inequities in health . Section title: Explanatory variables Educational score: 1.416027545928955 Domain: other Document type: Other Language: en Place of Residence was determined through the degree of urbanisation of the municipality and the specific region ( Bundesland ). The first variable was composed of three categories: cities (densely populated areas), towns and suburbs (intermediate-density areas), and villages (thinly populated areas). The second variable indicated the federal states ( Bundesländer ) in Germany. Section title: Explanatory variables Educational score: 1.6165776252746582 Domain: other Document type: Study Language: en Race, ethnicity, culture, and language were indicated by proxy variables: since the EHIS did not assess either of these explicitly. We selected the respondent's country of origin and nationality and then classified them as either born in Germany, in Europe or outside Europe. Although short at measuring complexities of identity, these variables have shown utility as ethnicity proxies in European countries where no information on race or ethnicity is gathered . Section title: Explanatory variables Educational score: 1.2095962762832642 Domain: other Document type: Other Language: en Occupation was operationalised based on the respondents’ current working situation: in paid employment, unemployed, retired, unable to work, (unpaid) household work and others. Section title: Explanatory variables Educational score: 1.7131208181381226 Domain: biomedical Document type: Study Language: en Sex (to identify as a female) was a prerequisite for participant inclusion in the analysis. Gender and religion were not captured by the EHIS. Section title: Explanatory variables Educational score: 1.6590347290039062 Domain: biomedical Document type: Study Language: en Education was measured following the ISCED-2011 classification . Since only 6 participants had primary education or less, the first three categories were combined into “less than upper secondary education”. Section title: Explanatory variables Educational score: 1.7467470169067383 Domain: biomedical Document type: Study Language: en Socioeconomic status was operationalised through household income and was divided into five quintile groups: the 20% with the lowest income were coded 1, and the 20% with the highest income were coded 5 . Section title: Explanatory variables Educational score: 1.7948428392410278 Domain: other Document type: Study Language: en Social capital was considered through six variables: social network dimensions (none, 1–2, 3–5, 6 or more), perceived social support (a lot, some, uncertain, little, or no concern) and ease in available help (very easy, easy, possible, difficult, or very difficult). Further, three proxy variables were also included: marital status (single, married, legally separated/divorced or widowed), type of household (alone, with a partner, with a partner and children, with children, or other) indicating the availability of family support, and partner cohabitation (yes or no). Section title: Explanatory variables Educational score: 2.6317989826202393 Domain: biomedical Document type: Study Language: en For the Plus dimension, the Global Activity Limitations Indicator (GALI), a self-report of the extent of limitation experienced in the last six months was considered, with possible answers: severely limited, mildly limited, or not limited . Age (50–69 years old) was required to be included in the analysis and was treated as a confounder in the regression analyses. Section title: Analytic approach Educational score: 3.675934076309204 Domain: biomedical Document type: Study Language: en Descriptive analytics, including frequencies and percentages, were calculated for all variables. A complete case analysis was conducted, i.e. cases with missing data were excluded listwise. The total sample was restricted to women aged 50–69 . Among these women, those who did not respond on whether they underwent mammography (n = 15), their place of residence (n = 384), the degree of urbanisation of their place of residence (n = 213), the household's income (n = 122), their level of education (n = 14), their social network dimensions (n = 11), their perceived social support (n = 46), the available help (n = 81), the type of household (n = 56), their marital status (n = 13), their partnership cohabitation status (n = 30), their working situation (n = 10), their country of origin (n = 11), their citizenship (n = 7), their GALI (n = 7) were excluded. Hence, the final total sample size of the study was 4761 participants. Section title: Analytic approach Educational score: 3.3134334087371826 Domain: biomedical Document type: Study Language: en Sampling weights were not used in analyses, as the sampling weights provided in the German EHIS data were derived from variables included in the analyses (education, urbanisation and age), which could lead to multicollinearity and biased standard error estimation. We report sensitivity analyses applying the sampling weights in both analytical strategies in Appendix A and show the correlations between sampling weights and variables in the analyses in Appendix B . The central aim of this article was to compare the estimation of women at higher risk of never attending BCS using two different analytical strategies: (a) evidence-informed regression and (b) decision tree-based regression. Section title: Analytical strategy a: evidence-informed regression Educational score: 2.4448769092559814 Domain: biomedical Document type: Review Language: en The evidence-informed analytical strategy builds a full cross-classification matrix based on social dimensions identified as relevant in the literature. A recent scoping review pinpointed migration background, socioeconomic position (based on income), degree of urbanisation, and partner cohabitation as significant dimensions for BCS attendance prediction . Section title: Analytical strategy a: evidence-informed regression Educational score: 2.37646222114563 Domain: biomedical Document type: Study Language: en For this analysis, country of origin was dichotomised as born inside or outside Germany, income was dichotomised into low (categories 1 and 2) and high (categories 3, 4 and 5), degree of urbanisation was dichotomised in people living in cities (urban) and people living in towns, suburbs or rural areas (rural), and partner cohabitation was already a dichotomous variable (yes/no). The cross-classification of all social positions led to 16 intersectional groups: 2 (country of origin) ∗ 2 (income) ∗ 2 (degree of urbanisation) ∗ 2 (partner cohabitation) ( Table 1 ). Table 1 Evidence-informed intersectional groups on lifetime BCS attendance. Table 1 Country of origin Income Degree of urbanisation Partner cohabitation Intersectional group name Germany High Urban Yes HGUY No HGUN Rural Yes HGRY No HGRN Low Urban Yes LGUY No LGUN Rural Yes LGRY No LGRN Other than Germany High Urban Yes HOUY No HOUN Rural Yes HORY No HORN Low Urban Yes LOUY No LOUN Rural Yes LORY No LORN Section title: Analytical strategy a: evidence-informed regression Educational score: 3.0172951221466064 Domain: biomedical Document type: Study Language: en For the purpose of comparison, univariate models were initially constructed for each of the four individual predictors and age. Next, a multivariable model that included all main effects was estimated. Section title: Analytical strategy a: evidence-informed regression Educational score: 4.059789180755615 Domain: biomedical Document type: Study Language: en Following this, a multivariate logistic regression with the full cross-classification matrix as the main predictor was performed to estimate the odds ratio (OR) of never attending BCS adjusted by age. Discriminatory accuracy (DA) was estimated through the area under the receiver operating characteristics curve (AUC) with a 95% confidence interval (CI), indicating how well each model discriminates between women attending and women never attending BCS. DA is considered absent or very small when 0.5 ≤AUC≤ 0.6, moderate when 0.6< AUC ≤0.7, large when 0.7< AUC ≤0.8 and very large AUC>0.8 . These statistical procedures were carried out using Stata version 17.0. Section title: Analytical strategy b: decision tree-based regressions Educational score: 3.8943252563476562 Domain: biomedical Document type: Study Language: en The second analytical strategy consisted of two steps. First, building an explorative decision tree with the total sample size to identify homogeneous subgroups of women at higher risk of never attending BCS in Germany. Second, performing a multivariate logistic regression using the outcome of the decision tree adjusted by age to estimate the OR of never attending BCS. Section title: Analytical strategy b: decision tree-based regressions Educational score: 4.020599365234375 Domain: biomedical Document type: Study Language: en There is no consensus on which decision tree better operates on binary outcomes. In this study, we trained three different algorithms: Classification and Regression Tree (CART), Conditional Inference Tree (CIT) and C5.0. The CART algorithm makes splitting decisions based on the lowest gini impurity (or entropy) coefficient among all potential splits (i.e. every category or step of every variable) . CART does not provide statistical significance measures and potentially overestimates the influence of variables with many categories. CIT addresses these limitations by utilising a formal statistical hypothesis in growing decision trees and mitigating variable selection bias by splitting the selection process into two steps . C5.0 uses the entropy coefficient of the imputed variables to generate splits plus adaptative boosting and winnowing . Section title: Analytical strategy b: decision tree-based regressions Educational score: 4.0576066970825195 Domain: biomedical Document type: Study Language: en All three decision tree algorithms (CART, CIT, C5.0) were built using the entire dataset and the same subdivision of the data when performing cross-validation. Cost weights were applied to distribute the sums of weights equally for cases and non-cases, given the (relative) rareness of the outcome in the dataset (10.38% prevalence). Parameters were hypertuned and optimised by two performance measures: sensitivity (i.e. enhancing detection of positive cases) and the Area Under the Precision-Recall Curve (i.e. improving overall precision-recall performance for unbalanced datasets) . Decision trees were grown using the tune function from the “mlr3tuning” optimisation R packages in R version 4.4.0. This package integrates essential packages for building CART “rpart” , CIT “partykit” , and C5.0 “C50” . Section title: Analytical strategy b: decision tree-based regressions Educational score: 3.816375732421875 Domain: biomedical Document type: Study Language: en After inductively identifying the best-performing decision tree, the final nodes were deductively used as predictors for a multivariate logistic regression adjusted by age, where the ORs and DA of the model were estimated. This statistical procedure was performed using the Stata version 17.0. Estimations, performance and interpretability of both analytical strategies were compared and discussed. Section title: Descriptive statistics of the sample Educational score: 4.022605895996094 Domain: biomedical Document type: Study Language: en Summary descriptive statistics of the sample can be found in Table 2 . The total sample size is 4761. Of those, 4267 attended BCS at least once in their lifetime, and 494 did not. Relative frequencies for never attending BCS among the different PROGRESS-Plus characteristics were assessed. As expected, women aged 65–69 had the lowest prevalence (6.55%), and women aged 50–54, had the highest prevalence (18.58%). For SES, women in the lowest quintile attended BCS the least (14.07%), and those in the highest quintile attended BCS the most (9.79%). Almost contradicting, women with the highest education attainment, doctoral or equivalent, attended BCS the least (14.75%) and women with bachelor or equivalent educational attainment the most (9.10%). Based on the country of origin, women born in Germany (10.56%) had the lowest attendance rates compared to women born elsewhere. However, women of another European nationality attended the least (12.05%) and women of German nationality the most (10.31%). Regarding the place of residence, women living in cities (11.16%), women living in Berlin (13.69%) and Saarland (13.39%) had the lowest BCS attendance rate. Table 2 Descriptive PROGRESS-Plus characteristics on BCS attendance among targeted women in Germany. Relative frequencies per column and variable are displayed. Table 2 Attended BCS Never attended BCS (N = 494) Total Age 50-54 916 (21.5%) 209 (42.3%) 1125 (23.6%) 55-59 1149 (26.9%) 116 (23.5%) 1265 (26.6%) 60-64 1104 (25.9%) 92 (18.6%) 1196 (25.1%) 65-69 1098 (25.7%) 77 (15.6%) 1175 (24.7%) Income 1Q 458 (10.7%) 75 (15.2%) 533 (11.2%) 2Q 687 (16.1%) 76 (15.4%) 763 (16.0%) 3Q 795 (18.6%) 89 (18.0%) 884 (18.6%) 4Q 1010 (23.7%) 111 (22.5%) 1121 (23.5%) 5Q 1317 (30.9%) 143 (28.9%) 1460 (30.7%) Educational group Lower secondary or lower 219 (5.1%) 28 (5.7%) 247 (5.2%) Upper secondary 1515 (35.5%) 170 (34.4%) 1685 (35.4%) Post-secondary 609 (14.3%) 78 (15.8%) 687 (14.4%) Bachelor or equivalent 1120 (26.2%) 112 (22.7%) 1232 (25.9%) Master or higher a 804 (18.8%) 106 (21.4%) 900 (19.2%) Country of origin Germany 3948 (92.5%) 466 (94.3%) 4414 (92.7%) Outside of Germany a 319 (7.5%) (28) b (5.6%) 347 (7.3%) Citizenship German or other a 4267 (100%) 494 (100%) 4761 (100%) Degree of urbanisation City 1712 (40.1%) 215 (43.5%) 1927 (40.5%) Town or suburb 1803 (42.3%) 210 (42.5%) 2013 (42.3%) Rural area 752 (17.6%) 69 (14.0%) 821 (17.2%) Region Baden-Württemberg 459 (10.8%) (43) b (8.7%) 502 (10.5%) Bavaria 522 (12.2%) 71 (14.4%) 593 (12.5%) Berlin/Brandenburg a 503 (11.8%) 83 (14.7%) 576 (12.1%) Hesse 260 (6.1%) (31) b (6.3%) 291 (6.1%) Lower Saxony/Bremen a 368 (8.8%) (35) b (7.1%) 403 (8.5%) North Rhine-Westphalia/Rhineland-Palatinate a 991 (23.2%) 102 (20.6%) 1093 (22.9%) Saarland 427 (10.0%) 66 (13.4%) 493 (10.4%) Saxony/Saxony-Anhalt/Thuringia a 377 (8.8%) (37) b (7.4%) 414 (8.7%) Schleswig-Holstein/Hamburg/Mecklenburg-Vorpommern a 360 (8.4%) (36) b (7.2%) 397 (8.3%) Quality of social network 1–2 or less a 557 (13.1%) 82 (16.6%) 639 (13.5%) 3-5 2086 (48.9%) 252 (51.0%) 2338 (49.1%) >6 1624 (38.1%) 160 (32.4%) 1784 (37.5%) Perceived social support A lot 930 (21.8%) 116 (23.5%) 1046 (22.0%) Some 2529 (59.3%) 260 (52.6%) 2789 (58.6%) Uncertain 523 (12.3%) 77 (15.6%) 600 (12.6%) Little or none a 275 (6.7%) (41) b (8.3%) 326 (6.8%) Available help Very easy 1414 (33.1%) 165 (33.4%) 1579 (33.2%) Easy 1702 (39.9%) 176 (35.6%) 1878 (39.4%) Possible 726 (17.0%) 93 (18.8%) 819 (17.2%) Difficult 291 (6.8%) (34) b (6.9%) 325 (6.8%) Very difficult 134 (3.1%) (26) b (5.3%) 160 (3.4%) Marital status Single 481 (11.3%) 95 (19.2%) 576 (12.1%) Married 2706 (63.4%) 267 (54.0%) 2973 (62.4%) Widowed 449 (10.5%) (37) b (7.5%) 486 (10.2%) Divorced 631 (14.8%) 95 (19.2%) 726 (15.2%) Type of household Alone 1219 (28.6%) 168 (34.0%) 1387 (29.1%) With children 145 (3.4%) (21) (4.3%) 166 (3.5%) With a partner 2100 (49.2%) 172 (34.8%) 2272 (47.7%) With a partner and children 435 (10.2%) 86 (17.4%) 521 (10.9%) Other 368 (8.6%) (47) b (9.5%) 415 (8.7%) Working situation In paid employment 2531 (59.3%) 332 (67.2%) 2863 (60.1%) Unemployed/Others a 135 (3.1%) (20) b (4.0%) 155 (3.3%) Retired 1258 (29.5%) 90 (18.2%) 1348 (28.3%) Household work (unpaid) 181 (4.2%) (25) b (5.1%) 206 (4.3%) Unable 162 (3.8%) (27) b (5.5%) 189 (4.0%) Partner cohabitation Yes 2767 (64.8%) 280 (56.7%) 3047 (64.0%) No 1500 (35.2%) 214 (43.3%) 1714 (36.0%) Experienced limitation Severely limited 320 (7.5%) (44) (8.9%) 364 (7.6%) Mildly limited 1339 (31.4%) 137 (27.7%) 1476 (31.0%) Not limited 2608 (61.1%) 313 (63.4%) 2921 (61.4%) a Multiple categories were displayed collapsed when cell sizes <20 observations to avoid re-identifiability according to EHIS anonymisation rules. b Cells containing between 20 and 49 observations are individually flagged according to EHIS anonymisation rules. Section title: Descriptive statistics of the sample Educational score: 1.8479958772659302 Domain: biomedical Document type: Study Language: en When considering social capital, the highest prevalence of never attending BCS was among those with no social network (13.35%), those with little perceived social support (13.36%), and those who find it very difficult to get help from neighbours (16.25%). Section title: Descriptive statistics of the sample Educational score: 1.9160374402999878 Domain: biomedical Document type: Study Language: en Single women (16.49%) showed the highest rates of never attending BCS among all marital statuses. Women living with a partner and children (16.51%), women unable to work (13.76%), unemployed women (13.68%), and women not cohabiting with a partner (12.49%) displayed the highest prevalences. Lastly, severely limited women (12.09%) had the lowest attendance rates among their PROGRESS-Plus dimension. Section title: Analytical strategy a: evidence-informed regression Educational score: 1.860916018486023 Domain: biomedical Document type: Review Language: en Based on a recent scoping review , four PROGRESS-Plus variables were relevant for predicting lifetime BCS attendance: migration background, income, urbanisation degree and partnership cohabitation . Section title: Analytical strategy a: evidence-informed regression Educational score: 4.072527885437012 Domain: biomedical Document type: Study Language: en Univariate logistic regression analyses separately estimated the effects of these four variables ( Table 3 ). Only cohabitation significantly predicted BCS attendance, with women living alone having higher odds of never attending. Age also had a significant relationship with BCS attendance. Table 3 Univariate logistic regression on never attending BCS in Germany. Table 3 Sociodemographic variables OR 95% CI R 2 model AUC model Income High 1 Low 1.20 (0.98–1.47) 0.0010 0.5187 Country of origin Germany 1 Not Germany 0.74 (0.50–1.11) 0.0007 0.5090 Degree of urbanisation Urban 1 Rural 0.87 (0.72–1.05) 0.0007 0.5170 Partner cohabitation Yes 1 No 1.41∗∗∗ (1.17–1.70) 0.0039 0.5408 Age 50–54 1 55–59 0.44∗∗∗ (0.35–0.56) 60–64 0.37∗∗∗ (0.28–0.47) 65–69 0.31∗∗∗ (0.23–0.40) 0.0317 0.6225 Section title: Analytical strategy a: evidence-informed regression Educational score: 4.107833385467529 Domain: biomedical Document type: Study Language: en Multivariate logistic regression was performed to capture the effects of each predictor when adjusting for covariates and age ( Table 4 ). Here, the only relationship that showed a statistically significant relationship with BCS attendance was partner cohabitation, with 1.45 higher odds (p < 0.001) for women not cohabitating with their partners. Table 4 Multivariate logistic regression on never attending BCS in Germany (main effects model). Table 4 Sociodemographic variables OR 95% CI Income High 1 Low 1.21 (0.98–1.49) Country of origin Germany 1 Not Germany 0.68 (0.46–1.02) Degree of urbanisation Urban 1 Rural 0.91 (0.75–1.11) Partner cohabitation Yes 1 No 1.45∗∗∗∗ (1.19–1.76) Age 50–54 1 55–59 0.43 ∗∗∗ (0.34–0.56) 60–64 0.36 ∗∗∗ (0.28–0.47) 65–69 0.29 ∗∗∗ (0.22–0.38) R 2 0.0394 AUC-ROC 0.6539 A complete case analysis only based on the variables would have resulted in 300 more participants, but the results do not change meaningfully – see Appendix C . Section title: Analytical strategy a: evidence-informed regression Educational score: 1.9797321557998657 Domain: biomedical Document type: Study Language: en Sixteen intersectional groups were created based on the combination of the four variables identified in the literature. Fig. 1 depicts the size and prevalence of each group. Fig. 1 Prevalence and size across the sixteen evidence-informed intersectional groups. a Cells containing between 20 and 49 observations are individually flagged according to EHIS anonymisation rules. Fig. 1 Section title: Analytical strategy a: evidence-informed regression Educational score: 4.097665786743164 Domain: biomedical Document type: Study Language: en Following this, an unweighted logistic regression was performed . As a reference group, we chose the one expected to have the highest attendance rate - based on the multivariate regression and Pedrós Barnils et al. - high-income women born outside Germany, living in urban areas with a partner (HOUY). Table 5 Full cross-classified multivariate logistic regression with evidence-informed intersectional groups. Table 5 OR 95% CI Intersectional groups HOUY 1 HGUY 2.49 (0.88–7.04) HGUN 2.97∗ (1.04–8.45) HGRY 1.92 (0.69–5.40) HGRN 2.84 (0.99–8.14) LGUY 1.96 (0.62–6.18) LGUN 3.71∗ (1.27–10.89) LGRY 2.81 (0.98–8.08) LGRN 3.24∗ (1.11–9.47) HOUN 3.11 (0.85–11.39) HORY 0.74 (0.16–3.46) HORN 3.15 (0.64–15.48) LOUY 0.66 (0.07–6.26) LOUN 4.00 (0.91–17.49) LORY 0.52 (0.05–4.82) LORN 9.48∗∗ (2.24–40.10) Age 50–54 1 55–59 0.43∗∗∗ (0.33–0.54) 60–64 0.35∗∗∗ (0.27–0.45) 65–69 0.29∗∗∗ (0.22–0.38) R 2 0.0445 AUC-ROC 0.6618 ∗p-value <0.05; ∗∗p-value <0.01; ∗∗∗ p-value <0.001. HGUY - high-income, born in Germany, urban, cohabitation. HGUN - high-income, born in Germany, urban, no cohabitation. HGRY - high-income, born in Germany, rural, cohabitation. HGRN - high-income, born in Germany, rural, no cohabitation. LGUY - low-income, born in Germany, urban, with cohabitation. LGUN - low-income, born in Germany, urban, no cohabitation. LGRY - low-income, born in Germany, rural, cohabitation. LGRN - low-income, born in Germany, rural, no cohabitation. HOUY - high-income, born outside Germany, urban, cohabitation. HOUN - high-income, born outside Germany, urban, no cohabitation. HORY - high-income, born outside Germany, rural, cohabitation. HORN - high-income, born outside Germany, rural, no cohabitation. LOUY - low-income, born outside Germany, urban, cohabitation. LOUN - low-income, born outside Germany, urban, no cohabitation. LORY - low-income, born outside Germany, rural, cohabitation. LORN - low-income, born outside Germany, rural, no cohabitation. Fig. 2 Odds Ratio (OR) with evidence-informed intersectional groups on never attending BCS in Germany. Fig. 2 Section title: Analytical strategy a: evidence-informed regression Educational score: 3.1607577800750732 Domain: biomedical Document type: Study Language: en Four intersectional groups were significantly associated with never attending BCS. Low income women not born in Germany and living in rural areas with no partner (LORN) showed the highest odds (OR = 9.48, p = 0.002). The confidence intervals for all these estimations were rather wide, increasing the uncertainty of the predicted estimations. The DA of the full cross-classification model was moderated and 0.0079 points higher than the main effects model. That indicates that the regression with intersectional groups discriminates slightly better between women attending or never attending BCS than the main effects model. Section title: Analytical strategy b: decision tree-based regression Educational score: 4.125537395477295 Domain: biomedical Document type: Study Language: en Out of the three algorithms, CART showed the highest sensitivity and balanced accuracy performance. For more information on the hypertuned models, see Appendix D . The inner performance (i.e. evaluated on trained data) of CART was: 72.47% sensitivity, 51.35% specificity, 61.91% balanced accuracy, 14.71% positive predictive value and 94.15% negative predictive value. The moderate sensitivity suggests reasonable confidence in CART detecting women not attending BCS. However, the low specificity suggests small confidence in CART to identify negative cases (i.e. women attending BCS). The small positive predictive value indicates that many cases classified as positive (i.e. not attending BCS) are false positives. Nevertheless, the high negative predictive value indicates very few false negatives and, therefore, very high confidence that those cases classified as negative are negative (i.e. not assuming that a woman is attending BCS when she is not). Fig. 3 and Table 6 show the final decision tree and the emerged intersectional groups. Fig. 3 CART decision tree on never attending BCS in Germany. Fig. 3 Table 6 Intersectional groups on never attending BCS in Germany based on CART. Table 6 Group Intersectional groups Rank a Size, Prevalence H Women living with a partner, retired or doing unpaid household work 1 N = 882 Pr = 0.0454 E Widowed women living alone, with children, with a partner and children or other arrangements, residing in Baden-Württemberg, Berlin, Hesse, Mecklenburg-Vorpommern, Lower Saxony, North Rhine-Westphalia, Rhineland-Palatinate, Saxony, Saxony-Anhalt, and Schleswig-Holstein or Thuringia 2 N = 316 Pr = 0.0506 C Single, married or divorced women living in other living arrangements, with some or no perceived social support 3 N = 211 Pr = 0.0616 G Women living with a partner, who are either employed, unemployed, unable to work, or in other categories, and residing in Baden-Württemberg, Brandenburg, Hesse, Mecklenburg-Vorpommern, Lower Saxony, North Rhine-Westphalia, Rhineland-Palatinate, Saxony, Saxony-Anhalt, or Schleswig-Holstein 4 N = 918 Pr = 0.0730 B Single, married or divorced women living alone, with children, with a partner and children, with some or no perceived social support 5 N = 953 Pr = 0.1301 F Women living with a partner who are either employed, unemployed, unable to work, or in other working categories and residing in Bavaria, Berlin, Bremen, Hamburg, Saarland or Thuringia 6 N = 472 Pr = 0.1377 D Widowed women living alone, with children, with a partner and children or other arrangements, residing in Bavaria, Brandenburg, Bremen, Hamburg, or Saarland 7 N = 136 Pr = 0.1471 A Single, married or divorced women living alone, with children, with a partner and children or other arrangements, with little, uncertain or a lot of perceived social support 8 N = 873 Pr = 0.1707 Section title: Analytical strategy b: decision tree-based regression Educational score: 1.6437962055206299 Domain: other Document type: Study Language: en CART identified household type, marital status, working situation, region and perceived social support as relevant variables. The first splitting point, the root node, is the household type, where women living with a partner are split from all other household types. Women living with a partner are further split into working situations. Here, women retired or doing unpaid household work form a final node , and women employed, unemployed, unable to work, or others further split based on their region . Section title: Analytical strategy b: decision tree-based regression Educational score: 1.1736541986465454 Domain: other Document type: Other Language: en Women living alone, with children, with a partner and children or in other arrangements are further split based on marital status. Here, widowed women are separated from single, married or divorced women. Widowed women were lastly split based on their region . On the other hand, single, married or divorced women further split based on their perceived social support. Those with some or no perceived social support are separated from those with little, uncertain or a lot of perceived social support, who form a final node . The first group split one last time based again on their type of household: living alone, with children, or with a partner and children , and other arrangements . Section title: Analytical strategy b: decision tree-based regression Educational score: 4.048068523406982 Domain: biomedical Document type: Study Language: en An unweighted logistic regression with CART intersectional groups adjusted by age was carried out using the group with the lowest never-attended BCS prevalence (Group H) as the reference category . Table 7 Multivariate logistic regression with CART intersectional groups on never attending BCS in Germany. Table 7 OR 95% CI CART intersectional groups A 3.02∗∗∗ (2.02–4.50) B 2.18∗∗∗ (1.45–3.27) C 1.12 (0.58–2.18) D 3.43∗∗∗ (1.91–6.10) E 1.05 (0.57–1.90) F 2.54∗∗∗ (1.62–3.98) G 1.26 (0.81–1.96) H 1 Age 50–54 1 55–59 0.49∗∗∗ (0.37–0.62) 60–64 0.46∗∗∗ (0.35–0.60) 65–69 0.44∗∗∗ (0.32–0.60) R 2 0.0534 AUC-ROC 0.6726 Fig. 4 Odds Ratios (OR) from CART intersectional groups on never attending BCS in Germany. Fig. 4 Section title: Analytical strategy b: decision tree-based regression Educational score: 3.5133650302886963 Domain: biomedical Document type: Study Language: en After adjusting by age, four CART intersectional groups showed a statistically significant difference compared to group H. Group D showed the highest odds of never attending BCS (OR = 3.43; p < 0.001), and Group E the lowest odds (OR = 1.05; p = 0.88). Section title: Analytical strategy b: decision tree-based regression Educational score: 2.6789815425872803 Domain: biomedical Document type: Study Language: en The total DA of the model CART was moderate . This value is 0.0108 points higher than the evidence-informed regression, indicating better discriminatory accuracy than the evidence-informed approach. Section title: Summary of findings Educational score: 3.118177652359009 Domain: biomedical Document type: Study Language: en This study aimed to identify intersectional groups of women aged 50–69 at higher risk of never attending BCS in Germany comparing two different analytical strategies: evidence-informed regression and decision tree-based regression. Section title: Summary of findings Educational score: 2.3850200176239014 Domain: biomedical Document type: Study Language: en The evidence-informed approach identified low-income women who were not born in Germany, residing in rural areas and are not cohabitating with their partner as those at the highest risk of never attending BCS. In contrast, the decision tree-based approach yielded additional insights regarding specific regions of residence and family status. In this regard, the highest-risk group comprised women living alone, with children, with a partner and children, or in other arrangements, residing in Bavaria, Brandenburg, Bremen, Hamburg, or Saarland. Section title: Summary of findings Educational score: 2.364452362060547 Domain: biomedical Document type: Study Language: en The evidence-informed intersectional group matrix presented low-income women not born in Germany living in rural areas and cohabiting with a partner as those with the lowest prevalence of never attending BCS and low-income women not born in Germany living in rural areas and not cohabiting with a partner as those with the highest prevalence. These two groups differ solely on partnership cohabitation, illustrating a classical intersectional hypothesis: the contingency of inequities, whereby discrimination experienced in a specific social position depends on its interactions with other social positions. Cohabitation with a partner acts as a determining factor for low-income women not born in Germany and living in rural areas on their likelihood of attending BCS. Section title: Summary of findings Educational score: 3.9141440391540527 Domain: biomedical Document type: Study Language: en The decision tree-based approach also identified household type as a relevant variable, revealing that women living with a partner generally had a lower risk of never attending BCS than those in other living arrangements. Several authors have previously conveyed the importance of partnership cohabitation and breast cancer screening attendance . Furthermore, living arrangements seem to play a role for those with some or no social support. The risk of never attending BCS was found to be half that of women with some or no social support who were living in other arrangements, compared to those living alone, with children, or with a partner and children. Furthermore, the role of perceived social support in the intersectional group identified as relevant (i.e. single, married or divorced women living alone, with children, with a partner and children or in other arrangements) is unclear, as previously noted in the literature . Section title: Summary of findings Educational score: 2.242736339569092 Domain: biomedical Document type: Study Language: en Lastly, the decision tree split by federal states twice in its third node. In both splits, women residing in Bavaria, Bremen, Hamburg, and Saarland indicate a higher risk of never attending BCS. These four federal states have been identified in other studies as having lower BCS attendance after invitation , reinforcing the higher compliance with preventive behaviours in former East Germany compared to the West. The use of the decision tree facilitated the identification of regional disparities among specific intersectional subgroups of women that would otherwise have remained unnoticed. Section title: Comparison of regression- and decision tree-based approaches Educational score: 3.80273699760437 Domain: biomedical Document type: Study Language: en The interpretability of the decision tree-based regression was slightly enhanced compared to the cross-classified regressions since it entailed fewer intersectional groups. Moreover, this reduction in dimensions did not entail a loss of information. On the contrary, the discriminatory accuracy of the model was slightly higher than the evidence-informed regression. Furthermore, the confidence intervals of the decision tree-based regression estimations are reduced (i.e. smaller variance), suggesting a more precise estimation of effect sizes. Section title: Comparison of regression- and decision tree-based approaches Educational score: 2.3847382068634033 Domain: biomedical Document type: Study Language: en Nevertheless, in this study no clearly discernible pattern of inequalities emerged among the PROGRESS-Plus characteristics, strengthening the heterogeneous findings reported by Pedrós Barnils et al. . Additional variables beyond the categorisation of sociodemographic factors, such as process-oriented variables (e.g. unpaid household work), could be explored to assess their relationship with BCS attendance. Section title: Comparison of regression- and decision tree-based approaches Educational score: 1.0877666473388672 Domain: other Document type: Other Language: en This article does not aim to defend the use of any approach over another. As the “no-free-lunch theorem” in the machine learning literature often states, no single model works best in all scenarios . Nonetheless, this article encourages peer colleagues to evaluate different analytical strategies to answer their research question, while being aware of the advantages and disadvantages offered by each approach. Section title: Comparison of regression- and decision tree-based approaches Educational score: 2.572256565093994 Domain: biomedical Document type: Study Language: en The evidence-informed approach synthesises existing research to identify variables that are relevant to BCS attendance, making a normative decision on which axis of inequality to explore. However, using repeatedly explored social dimensions may result in the stigmatisation of certain collectives and the under-exploration of others . Moreover, recommendations can only be formulated based on analysed social dimensions. Consequently, a potentially biased selection of variables can result in biased recommendations for developing interventions. Section title: Comparison of regression- and decision tree-based approaches Educational score: 3.7854485511779785 Domain: biomedical Document type: Study Language: en Conversely, the decision tree-based approach uses statistical algorithms to inductively identify patterns and relationships from the dataset . This approach is advantageous in revealing combinations of social dimensions not previously identified or explored, enabling more targeted interventions. Nevertheless, decision trees are susceptible to data quality, and their hierarchical structure might produce spurious results (i.e. the initial split has a significant impact on subsequent splits) . Moreover, given the uncommon application of decision trees in public health, no standardised procedures are yet defined, hence, many decisions are left to the discretion of the researcher (i.e. researcher bias). Section title: Comparison of regression- and decision tree-based approaches Educational score: 3.984280824661255 Domain: biomedical Document type: Study Language: en From a quantitative intersectionality perspective, the decision tree approach yields certain advantages for answering the question , “Who is at higher risk of never attending BCS?“ . The regression with a full cross-classification based on evidence-identified variables inevitably results in a loss of information due to the category simplification required to build the matrix . To maintain cells with sufficient size to preserve statistical power, variable categories are dichotomised, compromising the possibility of identifying non-linear patterns amid these categories . Decision trees allow for high dimensionality in the included variables (i.e. without risk of multicollinearity) and their categories (i.e. no need for dichotomisation). Section title: Strengths and limitations Educational score: 4.012105941772461 Domain: biomedical Document type: Study Language: en To the authors’ knowledge, this is the first study to compare regression- and decision tree-based approaches for identifying intersectional subgroups of women at higher risk of not attending BCS. However, the study is not without limitations, in particular the cross-sectional design of the survey, which impedes any causal inference from being drawn, and its self-report methodology, which may introduce response bias. The response rate for EHIS wave 3 in Germany was 21.6%, highlighting the necessity for caution when interpreting findings from studies utilising this dataset. Lastly, previous studies have indicated that EHIS may underestimate disparities in access to screening programmes . Section title: Conclusion Educational score: 4.042077541351318 Domain: biomedical Document type: Study Language: en The combination of regression and decision tree-based approaches provides a comprehensive strategy for identifying intersectional groups at higher risk of an outcome. In this study, the evidence-informed regression identified that low-income women who were not born in Germany lived in rural areas, and did not cohabit with their partner as being at the highest risk of never attending BCS. Conversely, the decision tree-based approach identified widowed women living alone, with children, with a partner and children, or in other arrangements, and residing in specific federal states (i.e. Bavaria, Brandenburg, Bremen, Hamburg, or Saarland) as the highest risk group. The decision tree-based approach slightly outperformed the regression-based approach in its overall performance and interpretability and added a nuanced, data-driven layer of analysis, that enhances the overall understanding of the PROGRESS-Plus characteristics that determine BCS attendance in Germany. Section title: CRediT authorship contribution statement Educational score: 1.0151022672653198 Domain: other Document type: Other Language: en Núria Pedrós Barnils: Writing – original draft, Visualization, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Benjamin Schüz: Writing – review & editing, Validation, Supervision, Methodology, Conceptualization. Section title: Ethical statement Educational score: 1.2238717079162598 Domain: other Document type: Other Language: en This study does not require ethical approval as it is a secondary analysis of de-identified data. Access to the data was granted by Eurostat, the European body for Statistics, and all authors have signed the individual confidentiality declaration following Regulation (EC) No 223/2009 . Section title: Financial disclosure statement Educational score: 1.009604573249817 Domain: other Document type: Other Language: en This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Open-access funding is provided by Bremen University. Section title: Declaration of interest statement Educational score: 0.9564821720123291 Domain: other Document type: Other Language: en The results and conclusions are mine and not those of Eurostat, the European Commission or any of the national statistical authorities whose data have been used. | Other | biomedical | en | 0.999998 |
PMC11699221 | Section title: Introduction Educational score: 3.7704050540924072 Domain: biomedical Document type: Other Language: en Research is an integral component of evidence-based medicine. Relevant and timely information about novel disease management, pharmacological advancements, and public health interventions is critical in modern healthcare. In this context, research has become a considered method of skill development and literature interpretation for clinicians . In addition to this, medical research has a direct impact on the relationship between patients and the healthcare system, and their trust in ever-evolving medical practices . Engaging pre-qualification/registration (i.e. primary degree to obtain registration as a doctor) medical students in research from their training period could be a useful strategy to facilitate capacity building and a positive research culture right from the start. Section title: Introduction Educational score: 2.8734817504882812 Domain: biomedical Document type: Other Language: en Combining clinical work and research is no easy feat. For example, the proportion of physicians engaged in research in the United States dropped from 4.7% in the 1980s to approximately 1.5% in 2019 . These statistics partly reflect the increasing demands and workload of clinical practice, the financial costs of pursuing both clinical practice and research, and the specialisation and knowledge required for undertaking research . It has been shown that physicians who participated in research during their time in medical school are more likely to contribute to greater research later in their careers . Despite such evidence, medical student research participation rates remain low . Section title: Introduction Educational score: 3.948256492614746 Domain: biomedical Document type: Review Language: en Although medical students view research opportunities as catalysts to obtaining entry into specialty training pathways, their participation in research remains limited . There is minimal research requirement as part of speciality training, and it depends on the interest of the individual along with the institution as to whether the individual is involved in research activities. Existing literature reveals several barriers that hinder medical student research participation including lack of opportunities, difficulty finding suitable supervisors and mentors, and a lack of time . Whilst the benefits of research involvement in medical school are favoured, student perception of research in this phase appears to be less favoured . The benefits of students participating in research do not appear to translate to higher levels of participation . A comprehensive synthesis on the current evidence related to enablers and barriers of medical student participation in research is required to inform policy and practice to mitigate these issues. Section title: Introduction Educational score: 4.057586193084717 Domain: biomedical Document type: Review Language: en Previous research has utilised the micro, meso, and macro frameworks to unpack enablers and barriers of an investigated topic . Macro factors involve policy considerations including legal, regulatory, and economic factors. Meso factors are related to the organisation and community, and micro factors are at the team and individual levels in the context of day-to-day practice. This review will utilise this framework to systematically unpack the enablers and barriers of medical student research participation at these levels. Doing so will not only enhance translation of review findings to policy and practice, but it will also strengthen the scholarship in this area. A preliminary mapping exercise of enablers and barriers to the macro, meso, and micro levels, based on information from the preliminary scoping searches, was completed during protocol development . The aim of this review was to synthesise the evidence on the enablers and barriers of research participation among students undertaking their pre-qualification medical studies, building on existing conceptual frameworks. Section title: Methods Educational score: 3.0067994594573975 Domain: biomedical Document type: Review Language: en Whilst using rapid review methodology considering available resources to undertake the review, systematic search methods were employed to ensure rigour. The review followed the World Health Organization (WHO) and the Cochrane guidelines for the conduct of rapid reviews . A protocol was developed and registered on the Open Science Framework . The WHO checklist for rapid reviews to demonstrate quality assurance of the review can be found in Supplementary Table 1 . Section title: Search Strategy and Data Sources Educational score: 4.2139668464660645 Domain: biomedical Document type: Review Language: en The databases searched in this review included PubMed, EMBASE, and PsycINFO. This decision was made following a preliminary scoping search to identify sources with the most relevant citations of the review topic. Detailed PICo (Population, Investigated phenomena and Context; Table 1 ) domains were used to create inclusion and exclusion criteria. Essentially, quantitative, qualitative, and mixed-methods studies of medical students investigating the enablers and barriers to research participation during their medical school years, within university and healthcare settings, were included. Supplementary Table 2 contains search strategies for all three included databases. Searches were run in July 2022 and updated in October 2023. Table 1 Inclusion and exclusion criteria Inclusion criteria Exclusion criteria Population Medical students (both undergraduate and postgraduate entry) Research masters (i.e. M.Phil) or PhD students, non-medical students (i.e. nursing, allied health, etc.), provisional entry students (i.e. pre-medical degree) Investigated phenomena Barriers and/or enablers to participation in research during medical school Participation in activities other than research (e.g. other work experience, teaching, training) Context Research in medical school or health settings while on placement Research outside of these contexts Study design Primary research studies -Quantitative designs (including RCTs, cohort studies, pre-post, cross-sectional etc.) -Qualitative designs (including interviews, focus groups, case studies) -Mixed-methods designs Secondary research (systematic reviews, other reviews) Editorials, opinion pieces, commentaries Position papers Conference abstracts and posters Research protocols Other English-language literature Publications dated 2012 onwards Full texts Non-English literature Non-published studies (e.g. grey literature, thesis and dissertation manuscripts) Section title: Search Outcomes Educational score: 3.862178325653076 Domain: biomedical Document type: Study Language: en All citations retrieved from the search were imported into Endnote X9™ and de-duplicated. Screening of titles and abstracts against the inclusion criteria was conducted using Covidence™ . For the title and abstract screening stage, 50 articles were screened by three reviewers (CM, HB, PM) together as a pilot exercise, with subsequent screening completed by two reviewers (CM, HB). Subsequently, at the full-text screening stage, three reviewers (CM, HB, PM) screened ten articles together to validate the process, with subsequent screening completed by two reviewers (CM, HB). During screening, conflict resolution was provided by a third reviewer (PM). Articles which met inclusion criteria were progressed to data extraction, while those which did not were excluded. The updated search did not yield any additional relevant articles. Section title: Methodological Quality Educational score: 3.908632516860962 Domain: biomedical Document type: Study Language: en Methodological quality of included studies was assessed using the modified McMaster Quantitative Critical Appraisal tool and the McGill Mixed Methods Appraisal Tool (MMAT) . They were chosen as they are freely available and are widely used. Methodological quality was assessed by two reviewers (CM, HB) and verified by a third reviewer (PM). All discrepancies were resolved through mutual discussions by the review team. All studies, regardless of their methodological quality, underwent data extraction and synthesis. Section title: Data Extraction Educational score: 2.1545894145965576 Domain: biomedical Document type: Study Language: en A data extraction template ( Supplementary Table 3 ) was developed and piloted on five studies by the review team prior to being finalised. Subsequent data extraction was carried out by two reviewers (CM, HB). Section title: Data Synthesis Educational score: 4.0704240798950195 Domain: biomedical Document type: Study Language: en A directed content analysis approach of a deductive nature was used to analyse the extracted data. Codes were developed using the micro, meso, and macro frameworks for both enablers and barriers. The data were then synthesised and mapped against these codes, and categories were developed for reporting . This approach was chosen as it enables conceptual extension of theory to progress scholarship. Directed content analysis is a more structured process than traditional content analysis and can complement a structured review process . Data synthesis was performed by three reviewers (CM, HB, PM) through regular discussions until consensus was reached to enable researcher-triangulation. The fourth reviewer (DD) validated the findings. Section title: Results Educational score: 4.07147741317749 Domain: biomedical Document type: Review Language: en A total of 521 studies were extracted from the database search. Following removal of 73 duplicates, 448 articles were progressed to title and abstract screening. Subsequently, 50 studies were progressed for full-text screening. Of these, 23 studies were excluded based on wrong setting ( n = 3), wrong outcomes ( n = 3), wrong intervention ( n = 5), wrong study design ( n = 7), and wrong study population ( n = 5), leaving 27 studies in the final review. A flow diagram of included studies is provided in Fig. 1 . Further information on excluded studies with reasons is available in Supplementary Table 4 . Fig. 1 PRISMA flowchart of included studies Section title: Results Educational score: 4.148248195648193 Domain: biomedical Document type: Study Language: en Of the 27 included studies, eight originated from India, three each from New Zealand and Saudi Arabia, and four from Pakistan. One study each was from Australia, Colombia, Nigeria, Poland, South Africa, Sweden, and the United Arab Emirates. Lastly, one study was conducted across Egypt, Algeria, Sudan, Joran, Syria, and Palestine, while another was conducted across the UK, New Zealand, Malaysia, Canada, and France. The majority of studies ( n = 22) were conducted in a university setting. The remaining studies were conducted in a hospital ( n = 2), at a student conference ( n = 2), or in a research programme setting ( n = 1). Twenty-five studies surveyed only undergraduate students. One study surveyed undergraduate and intercalating medical students and one surveyed both undergraduate and post-graduate students. The sample size of the studies ranged from 48 to 2989 participants. The most widely used study design was a quantitative survey ( n = 26), while only one study employed a mixed-methods design. There were no qualitative studies. Common variables measured across most studies included student demographic information, level of research knowledge, research practices/experiences (including publication rates), general attitudes towards research, enablers/motivators for research involvement, barriers to research involvement, and future research goals/intentions. Further information about study characteristics is available in Table 2 . Table 2 Study characteristics Author Country Setting Participants Study design/measurement tool Outcome measures Alamri et al. 2019a New Zealand University Undergraduate students ( n = 48) Mixed-methods: qualitative, cross-sectional survey + retrospective analysis Publication rates, perceived barriers and motivators to pursuing research projects, supervisor satisfaction with research programme Alamri et al. 2019b New Zealand University Undergraduate students (years 2 and 3, n = 249) Quantitative, cross-sectional survey Research awareness and attitudes, motivators, and barriers to research Alamri et al. 2021 New Zealand University Junior medical students ( n = 253), intercalating medical students ( n = 10), senior medical students ( n = 323) Quantitative, cross-sectional survey Research engagement, motivation type (intrinsic vs extrinsic), effect of motivation type on other factors surrounding research engagement AlGhamdi et al. 2014 Saudi Arabia University Years 4 and 5 undergraduate students ( n = 172) Quantitative, cross-sectional survey Perceptions of research importance/impact; obstacles to research; research practice and experiences; sociodemographic information Assar et al. 2018 Egypt, Algeria, Sudan, Jordan, Syria, Palestine University Undergraduate medical students Multi-centre, quantitative, cross-sectional survey Demographics, knowledge, attitudes, practices, perceived barriers Awofeso et al. 2020 Nigeria University Undergraduate medical students ( n = 221) Quantitative, cross-sectional survey Knowledge of medical research, perceived barriers to research Baig et al. 2013 Pakistan University (private = 2, public = 2) Medical students ( n = 398) Quantitative, cross-sectional survey Year, institution, participation in research and intention, previous experience, satisfaction, incentives, suggestions for improvement Bonilla-Escobar et al. 2017 Colombia University Medical students ( n = 133) Quantitative, cross-sectional survey Sociodemographic information, research influences, affiliations, productivity, extracurricular activities, research motivations, career-research relations, research benefits and professional plans, personal attributes Chellaiyan et al. 2019 India University (private) Undergraduate students ( n = 344) Cross-sectional survey Demographic information, knowledge/perceptions of research, attitudes, practice, barriers Funston et al. 2016 UK ( n = 454) NZ ( n = 115) Canada ( n = 110) Malaysia ( n = 106) France ( n = 105) University Medical students Demographic information, research perceptions (experience, barriers, financial implications), future goals (incentives, barriers, career goals) Hada et al. 2021 India Medical college, hospital Undergraduate medical students ( n = 292) Cross-sectional survey Demographic information, student attitude towards research, attitude for sustaining research interest (if reported involvement) Jimmey et al. 2013 India University, medical conference Undergraduate (2nd–5th year MBBS, n = 114) Cross-sectional survey Research involvement, difficulties faced during research, reasons for research involvement Kharraz et al. 2016 Saudi Arabia University Undergraduate students (years 2 and 3, n = 221) Cross-sectional survey Perceived barriers towards research engagement Kini et al. 2017 India University Undergraduate students ( n = 220) Cross-sectional survey Attitude towards research and its career impacts, perceptions towards research, obstacles to research Kumar et al. 2019 Pakistan University Undergraduate (years 3–5, n = 687) Cross-sectional survey Barriers experienced by medical students in conducting research Mahmood-Shah et al. 2017 Pakistan University Undergraduate ( n = 294) Cross-sectional survey Attitudes, knowledge, and practices of research; perceived motivation, barriers, and interventions; intentions for future research Muhandiramge et al. 2021 Australia University Undergraduate and postgraduate ( n = 704) Cross-sectional survey Research experience; understanding of research terms; attitudes towards research (barriers, motivators) Nel et al. 2014 South Africa University Undergraduate ( n = 733) Cross-sectional survey Demographic information, interest in specialisation, extent of previous research involvement, general attitude towards research, factors influencing attitude towards research Noorelahi et al. 2015 Saudi Arabia University Undergraduate (years 3–5, n = 233) Cross-sectional survey Attitudes to and practice of research, barriers to conducting research Omprahash et al. 2019 India University Undergraduate (year 1, n = 205) Cross-sectional survey Knowledge of research, factors promoting positive attitude towards research and encouraging research involvement, perceived barriers to research Rani and Priya 2014 India University Undergraduate 2nd + 3rd years ( n = 308) Cross-sectional survey Demographic information, knowledge, and attitude of research methodology/statistics, research practices Sayedalamin et al. 2018 UAE Medical student conference Undergraduate ( n = 288) Cross-sectional survey Research attitudes and practices, barriers to research Shahab et al. 2013 Pakistan University Undergraduate (year 2–5, n = 160) Cross-sectional survey Student knowledge of research activities, perceived barriers, student attitudes Singh et al. 2021 India Teaching hospital Undergraduate (year 2, n = 217) Cross-sectional survey (pre and post 2-year workshop) Comparison of knowledge, attitude, and practice between pre and post survey Sobczuk et al. 2022 Poland University Undergraduate (2nd year n = 391, 5th year n = 695) Cross-sectional survey Scientific interest and participation, opinions on research issues, perception of potential barriers to research Stockfelt et al. 2016 Sweden University Undergraduate ( n = 471) Cross-sectional survey, mixed methods Medical student interest in research, disincentives for research, how students get involved, types of research Yerpude and Jogdand 2016 India University Undergraduate (final year, n = 282) Cross-sectional survey Demographic information; student knowledge, attitudes, and barriers Section title: Methodological Quality Educational score: 4.089237689971924 Domain: biomedical Document type: Study Language: en A quality assessment was performed for each of the included studies, using the Modified McMaster’s Tool for quantitative studies ( n = 26) and MMAT ( n = 1) as outlined in Supplementary Tables 5a and b . All quantitative studies reported the study purpose and incorporated a relevant literature review. All studies were cross-sectional. All studies reported the sample size, but only 16 studies justified the sample size. Most outcome measures used were not reliable, and only under a quarter of studies used valid measures. A majority of studies ( n = 20) reported results in terms of statistical significance. All but one study used appropriate analysis methods and all studies reported on clinical importance of findings. All but two studies presented appropriate conclusions. The different components of the mixed-methods study did not adhere to the quality criteria of each tradition of the methods involved but met all other criteria on the MMAT tool. Section title: Barriers and Enablers of Medical Student Participation in Research Educational score: 3.2823216915130615 Domain: biomedical Document type: Study Language: en Utilising the macro, meso, and micro frameworks, enablers and barriers identified were mapped to the corresponding levels. Enablers of medical student participation in research were mapped to macro (career and financial incentives) and micro (skill acquisition and interest in research) levels, with no identified enablers at the meso level. Barriers were identified at all three levels. At the macro level, lack of training/information and financial constraints were noted. At the meso level, studies described difficulty finding supervisors, and at the micro level a lack of time, interest, and impact on studies/training were highlighted. Section title: Macro Level Enablers Educational score: 2.4057247638702393 Domain: biomedical Document type: Study Language: en Career and financial incentives were identified as enablers. Research was recognised in ten studies as an incentive to enter coveted medical training programmes and improvement of a doctor or student’s curriculum vitae [ 1 , 5 , 10 , 21 – 27 ]. Financial incentives were identified in five studies as a motivator for student participation in research . Section title: Micro Level Enablers Educational score: 2.5081887245178223 Domain: biomedical Document type: Study Language: en Skill acquisition and interest in research were the enablers identified at the micro level, interacting with day-to-day practice . Involvement in research for academic and skill development was the most recognised enabler of research participation in 11 studies [ 1 , 5 , 7 , 10 , 21 , 24 , 25 , 27 – 29 ]. Personal interest in research or on a particular topic promoted student participation in research in ten studies [ 1 , 5 , 21 – 24 , 26 – 28 ]. Section title: Macro Level Barriers Educational score: 3.244257926940918 Domain: biomedical Document type: Study Language: en Lack of training or information and financial constraints were mapped to this level. The absence of formal research training or a general lack of research awareness in universities was associated with decreased knowledge of available research opportunities and skills to participate in 18 studies [ 2 , 5 , 7 , 8 , 10 , 21 , 25 – 27 , 29 – 36 ]. Fourteen studies identified financial limitations as a barrier to research participation. Research was commonly completed on a volunteer basis or in conjunction with minimal financial aid through the enrolling university, which reduced student participation [ 1 , 2 , 5 , 7 , 21 , 27 – 29 , 31 – 36 ]. Section title: Meso Level Barriers Educational score: 1.992090106010437 Domain: biomedical Document type: Study Language: en Highlighted by 11 individual studies, access to suitable research mentors was a significant hurdle to pursuing research as a student [ 1 , 7 , 10 , 22 , 23 , 28 , 31 – 33 , 36 , 37 ]. Section title: Micro Level Barriers Educational score: 4.004533290863037 Domain: biomedical Document type: Study Language: en A lack of time, interest, and perceived impact on medical studies were barriers mapped to the micro level. Identified by 20 studies, increased workload and educational commitments related to medical studies limited time available to undertake research [ 1 , 2 , 5 , 7 , 10 , 21 – 30 , 32 – 36 ]. Ten studies identified a lack of interest in research as a barrier to participation during medical studies . Finally, participants in six studies noted that research participation in medical school might impact their medical education and prolong training . Section title: Discussion Educational score: 4.058935165405273 Domain: biomedical Document type: Review Language: en A systematic review and meta-analysis of medical student research in 2015 highlighted the association between medical student participation in research and improved short- and long-term scientific productivity, more informed career choices, and long-term success in academia . It further provided considerations for policy, decision makers, and researchers to progress this area. Despite these calls, engagement and participation of medical students in research and the resulting outputs and outcomes remain low . Our review explored enablers and barriers to medical student participation in research in order to further understand the prevailing gap. We subsequently mapped the enablers and barriers onto a conceptual framework to unpack different layers involved. Barriers to participation appear to outweigh enablers, thus substantiating the low participation rates in the literature . While identified enablers were mapped only at two levels of the framework, namely macro and micro, identified barriers were mapped to all three levels, indicating the wider extent of barriers across the continuum. Section title: Discussion Educational score: 4.083298683166504 Domain: biomedical Document type: Review Language: en The review by Amgad and colleagues exposed the lack of well-controlled high-quality prospective studies in this field . Eight years later, our review too echoes this finding. Studies included in our review were predominantly cross-sectional in design and utilising surveys to investigate participant perspectives. Apart from one mixed-methods study, all studies were quantitative, with an absence of qualitative studies to unpack the ‘how’ and ‘why’. Further, the surveys used in the included studies did not have established psychometric properties. The risk with in-house developed surveys without established psychometric properties is well-known. The field can only move forward when robust measures and tools are available . Given the diversity of approaches to research in different medical schools across the globe, availability and use of established surveys measures are essential. Furthermore, there is a need for qualitative studies so as to obtain in-depth experiences of students participating in research and their supervisors . Without these in-depth perspectives, available evidence will remain restricted. Section title: Discussion Educational score: 3.871466636657715 Domain: biomedical Document type: Study Language: en Medical students are a potential untapped resource that can be channelled to boost research outcomes. Medical students are generally interested and motivated to acquire new skills and education that enable them to progress their careers. However, some may find it hard to carry out research while juggling medical studies and associated workload. This could result in lower engagement and project completion rates. A recent Australian study by Fox and colleagues found that 33% of completed research projects medical students were involved in led to a peer-reviewed publication, while 51% led to outputs including conference presentations . This is slightly higher than the rates reported in the systematic review and meta-analysis by Amgad and colleagues in which only 30% of medical student projects resulted in peer-reviewed publications. Unless barriers at all levels of the system are tackled, these rates are unlikely to improve . Section title: Discussion Educational score: 3.9431889057159424 Domain: biomedical Document type: Other Language: en Structured and targeted support that streamlines student participation and involvement in research from an early stage can make a difference. This can be enacted at several levels. At the macro level, institutions can provide medical students with a research framework, educational resources to enable research, mentorship, and supervision. Integrating research into the mandatory curriculum may be more facilitatory than undertaking research in an extracurricular capacity . Provision of incentives and/or a good support and supervision structure could also assist students in not only engaging with research but also completing it to a high standard. At the meso and micro levels, research supervisors can improve research culture by providing adequate and high-quality supervision, and promoting and educating medical students on the outcomes of research, thus boosting interest and motivation. Further, early adoption of research, training, education, supervision, and culture is expected to ultimately improve medical student research participation. Section title: Discussion Educational score: 1.744921326637268 Domain: other Document type: Other Language: en Research may be highly sought after in some academic centres and countries that offer incentives to clinicians, researchers, and participants. However, in many other contexts such as within Australia, clinicians predominantly conduct research in their own time and are not financially incentivised. All academic titles are not remunerated and participation in research is voluntary. Institutions do not have a requirement for a certain number of research activities to be conducted; and hence, there is a large heterogeneity in the research output and quality amongst institutes. This highlights a systematic issue which needs to be addressed to promote research in all contexts. Section title: Strengths and Limitations Educational score: 2.749547004699707 Domain: biomedical Document type: Review Language: en Most studies included within the review were single-centre studies involving one university. Several studies present a potential selection bias as students that completed surveys may have been the ones that were interested or involved in research. Several processes were used in this review to ensure rigour. This review, although using rapid methods, followed systematic searching and adhered to guidelines from the WHO and Cochrane for the conduct of rapid reviews. Use of the micro, meso, and macro frameworks has enabled the visualisation of more barriers than enablers in this field. Section title: Conclusion Educational score: 3.2605221271514893 Domain: biomedical Document type: Other Language: en There are more perceived barriers than enablers of medical students’ participation in research. These can be addressed at several levels including academic and healthcare institutions, research supervision and mentorship, financial incentives to students, and research and provision of a supportive and positive research culture. Academic and healthcare institutes can partner in several ways to provide more support, structure, and incentives for students to engage in research. Further studies are needed, especially using qualitative methods, to understand in-depth experiences of students and their supervisors engaging with research during the student’s medical training period. Section title: Supplementary Information Educational score: 1.0263398885726929 Domain: other Document type: Other Language: en Below is the link to the electronic supplementary material. Supplementary file1 (DOCX 40 KB) | Other | biomedical | en | 0.999996 |
PMC11699231 | Section title: Introduction Educational score: 4.073132514953613 Domain: biomedical Document type: Study Language: en Environmental pollutants include industrial and agricultural chemicals, heavy metals, pharmaceutical agents, as well as products with hormonal activity . They lead to interruptions in the reproductive endocrine circuits, cytotoxicity, mutagenicity , growth arrest, hemato-biochemical deteriorations, immunosuppression, and redox imbalance in fish. Still further, these contaminants accumulate in fish tissues, potentially harming human well-being through the food chain . Pyrogallol, alternatively termed 1,2,3-trihydroxybenzene or 1,2,3-benzenetriol, is a phenolic compound derived from plants . It has a historical background in hair dyeing and continues to have diverse applications in modern industry . Its uses range from being a corrosion inhibitor and developer in holography and photography to being present in insecticides, colloidal metal solutions, and various medical and scientific products . Pyrogallol is naturally found in aquatic plant and as a contaminant in tannins, anthocyanins, flavones and alkaloids and released into environment during its isolation, disposal and industrial use . Section title: Introduction Educational score: 4.110886573791504 Domain: biomedical Document type: Study Language: en Pyrogallol improved the immune response by increasing myeloperoxidase activity, leukocyte respiratory burst activity, and lysozyme activity in zebrafish ( zebra danio ) against Acinetobacter baumannii infection . Pretreating brine shrimp ( Artemia franciscana ) with pyrogallol succeeded in counteracting Vibrio harveyi infection by its prooxidant action involving generation of hydrogen peroxide against . Section title: Introduction Educational score: 3.079200029373169 Domain: biomedical Document type: Other Language: en Microalgae are promising ingredients for feed sources due to their cellular metabolites comprising a blend of triglycerides, pigments, vitamins, and vital amino acids. Besides being a major component in aquafeed, their diverse range of biologically active ingredients can enhance the survival rates of farmed species and elevate the pigmentation and quality of edible meat [ , , , , ]. Along with their role as a cornerstone in aquaculture nutrition, they are highly valuable in combating ecotoxicity . Section title: Introduction Educational score: 3.60772442817688 Domain: biomedical Document type: Review Language: en Spirulina platensis , Chlorella vulgaris , and Moringa oleifera serve as effective interventions in mitigating the harmful effects of environmental contaminants on fish, and thereby potentially improving their health and overall well-being. These supplements could ameliorate hematological, hepatic, renal, and histopathological alterations caused by different toxicants, such as chlorpyrifos, diazinon, and oxyfluorfen . Section title: Introduction Educational score: 3.8853447437286377 Domain: biomedical Document type: Study Language: en Haematological outcomes provide straightforward and convincing methodological tools to comprehend the physiological processes and diagnose the somatic conditions of intoxicated fish . They identify anomalies within individuals even before observable negative effects on the ecosystem were noted . Despite various morphological, biochemical, and molecular analysis for evaluating the health status of fish, histopathologic evaluation remains a commonly employed technique in ecotoxicological investigations . Section title: Introduction Educational score: 4.142727851867676 Domain: biomedical Document type: Study Language: en C. gariepinus holds a prominent position as a widely favored freshwater fish globally, playing a crucial role as a significant nutritional source and a thriving species In terms of ecotoxicology, C. gariepinus is highly regarded as an outstanding model for evaluating the plausible harm of chemotoxicants, both within natural environments and controlled laboratory setups . As an indispensable source of human food, the toxicity in C. gariepinus could be transferred to human beings through the food chain. Therefore, the search for naturally occurring bioremediation strategies, with broad safety profiles, is of immense importance. These methods play a significant role not only in protecting the aquatic environment but also in ensuring human health. Upon thorough examination of scholarly articles, a notable gap exists in understanding the defensive properties of microalgae against toxicity triggered by pyrogallol in fish. Consequently, this study designs to address this gap by investigating hematological, biochemical, and histological markers as endpoints to explore this issue. Section title: Chemicals Educational score: 1.6354355812072754 Domain: biomedical Document type: Other Language: en Pyrogallol, acquired in the form of solid white crystals, was obtained from Sigma-Aldrich Chemical Company (USA). Its specifications include a chemical formula of C6H3(OH)3, quality level 200, a molecular weight of 126.11 g/mol, and a Chemical Abstracts Service number of 87-66-1. S. platensis (100 %) was sourced from Japan Algae Company, based in Tokyo, Japan, while C. vulgaris and M. oleifera were acquired from Sigma-Aldrich (Cairo, Egypt) Section title: Experimental protocol Educational score: 4.11827278137207 Domain: biomedical Document type: Study Language: en The animal study conducted in this research underwent thorough review and received approval from Al-Azhar University, Assiut Branch, Egypt. The Ethical Committee of the Faculty of Science at Al-Azhar University, Assiut Branch, granted approval for the experimental design and fish handling protocols, referencing approval number . A total of 150 C. gariepinus , weighing approximately 200 ± 25 g and measuring 25 ± 5 cm in length, were sourced from the Aquaponic Unit of Assuit University, Assuit, Egypt. Before the experiments, the fish were housed in 120-liter tanks for 14 days, where they were provided with dechlorinated tap water at a temperature of 26 ± 2 °C, pH levels between 7.2 and 7.6, oxygen levels maintained above 80 %, and a natural light cycle of 12 h each of light and dark. They were fed twice daily using commercial SKRETTING food formulated in line with Guideline No. 203 for testing the acute toxicity of chemicals in fish , containing 30 % protein. To minimize the impact of fish waste and ensure consistency, daily, 40 % of the water was exchanged. After the adaptation period, fifty fish were separated in a random fashion into five groups (30 fish per group). Each group was represented by three tanks, 10 fish each. Pyrogallol concentration was selected based on a previous research . The experimental groups were as follows: Group (1); control, Group (2); 10 mg/L of pyrogallol, Group (3); 10 mg/L of pyrogallol + S. platensis (20 g/kg diet) , Group (4); 10 mg/L of pyrogallol + C. vulgar is (50 g/kg diet) , Group (5); 10 mg/L of pyrogallol + M. oleifera (5 g/kg diet) . After being exposed for 15 days, six fish were chosen randomly and then subjected to an ice bath to relieve stress . Blood samples were gathered in tubes containing heparin for hematological evaluations, while non-heparinized tubes were employed for assessing biochemical markers and ions. This was done after tail cutting to collect blood from the caudal blood vessels. Section title: Hematological variables Educational score: 4.164623737335205 Domain: biomedical Document type: Study Language: en The red blood cell count (RBC, 10^6/mm^3) was determined using a Thoma hemocytometer chamber and Dacie's diluting fluid. The hematocrit ratio (Hct, %) was measured with a capillary hematocrit tube. Hemoglobin concentration (Hb, g/dL) was assessed through spectrophotometry at 540 nm utilizing the cyanomethemoglobin method described by Blaxhall and Daisley . Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were computed using formulas provided by Bain et al. . Section title: Hematological variables Educational score: 4.089452743530273 Domain: biomedical Document type: Study Language: en Peripheral blood smears stained with May-Grunwald-Giemsa were examined at × 100 oil immersion to analyze differential leukocytes. The count of white blood cells (WBC, 10 3 /mm 3 ) was determined following McKnight's protocol from 100 leukocytes on each slide to identify lymphocytes, neutrophils, and monocytes, as detailed by Kaya et al. . Section title: Morphological erythrocytic alterations and nuclear abnormalities Educational score: 4.095674514770508 Domain: biomedical Document type: Study Language: en After the exposure phase, blood smears were attained by making an incision in the caudal area and placing the blood on clean microscopic slides. These smears were then fixed in absolute methanol for 10 min and allowed to dry at room temperature. Afterward, the slides underwent staining with hematoxylin and eosin, followed by examination using a 40X objective lens and 10X eyepiece to detect micronucleated and morphologically changed RBCs. The identification requirements for micronuclei (MN) were based on established guidelines from prior studies to guarantee precise evaluation. Section title: Biochemical measurements Educational score: 4.116480827331543 Domain: biomedical Document type: Study Language: en Blood samples were collected and then centrifuged at 4000 rpm for 10 min to separate the serum, following . The isolated serum was analyzed for different biochemical parameters using a T80+ UV/VIS spectrophotometer (Bioanalytic Diagnostic Industry, Co.). Plasma alanine aminotransferase (ALT) , aspartate aminotransferase (AST) , total protein , glucose , total cholesterol (TC) , and creatinine were assessed using commercial kits from the Egyptian Company for Biotechnology, Egypt, according to the manufacturer's instructions. Alkaline phosphatase (ALP) was measured using a colorimetric kit from Novus Biologicals, USA, and uric acid (UA) was measured using a kit from Abnova, Taiwan. All these biochemical parameters were analyzed according to Rifai . Malondialdehyde (MDA) was quantified in serum according to the thiobarbituric acid reaction . Superoxide dismutase (SOD) activity was measured by its capacity to inhibit the phenazine methosulfate-mediated reduction of nitroblue tetrazolium dye, which produces a red product . Total antioxidant capacity (TAC) was determined following the protocol outlined by Koracevic et al. . Levels of interleukin-6 (IL-6) were measured according to an established method . Section title: Histopathological studies Educational score: 4.087496757507324 Domain: biomedical Document type: Study Language: en Samples of freshly sacrificed fish liver and kidney (N = 6) were immersed in 10 % neutral buffered formalin for preservation. The fixed samples underwent standard processing using paraffin embedding techniques. Subsequently, the samples were sliced into 5 μm-thick sections and stained with Hematoxylin and Eosin for comprehensive histological investigation , and Periodic Acid Schiff (PAS) staining was used to detect mucopolysaccharides . Section title: Histopathological studies Educational score: 3.958036184310913 Domain: biomedical Document type: Study Language: en To assess each histopathological parameter, six randomly chosen sections from four fish in each treatment group were examined. These parameters were categorized as follows: absent (-), scored 0-2%; slight (+), <25%; moderate (++), (25-50%); and severe (+++), indicating (> 50%) of the sections involved. An Olympus microscope model BX50F4 (Olympus Optical Co., Ltd., Tokyo, Japan) was used for scrutiny of the sections. Section title: Statistical analysis Educational score: 3.9792964458465576 Domain: biomedical Document type: Study Language: en Six biological replicates for each parameter outline above were statistically processed using the SPSS software (V 25) at a designated significance level of p < 0.05. Data were tested for normality using the Shapiro-Wilk test and for homogeneity of variance to ensure that the data were normally distributed, and the variances were consistent. One-way ANOVA followed by Duncan post-test. Data are depicted as mean ± SE. For each parameter, values in the same row with distinct superscript letters (a, b, c …) indicate a difference among groups. Section title: Ethics approval Educational score: 0.99295574426651 Domain: biomedical Document type: Other Language: en The animal research conducted at Al-Azhar University, Assiut Branch, Egypt received approval from the institution. The experimental setup and treatment of the fish were sanctioned by the Ethical Committee of the Faculty of Science, Al-Azhar University, Assiut Branch, Egypt, referenced as . This research did not involve human participants and was conducted following international, national, and institutional standards for the care and use of animals. Section title: Hematological variables Educational score: 4.233007431030273 Domain: biomedical Document type: Study Language: en Regarding hematological parameters, pyrogallol-exposed fish experienced a significant decrease in PCV and lymphocyte count, which was significantly ameliorated by microalgae interventions. C. vulgar is and M. oleifera were equally effective in normalizing PCV levels and significantly increasing lymphocyte counts. Neutrophil and eosinophil counts were significantly elevated in pyrogallol-exposed fish, and while S. platensis didn't significantly affect neutrophil levels, it significantly reduced eosinophil counts. C. vulgar is and M. oleifera supplementation significantly normalized these levels to those of the control group ( Table 1 ). Table 1 Effects of the studied microalgae on the hematological parameters in pyrogallol intoxicated- C. gariepinus. Table 1 Parameter Group Control Pyrogallol Pyrogallol + S. platensis Pyrogallol + C. vulgaris Pyrogallol + M. oleifera P value RBCs (million/mm 3 ) 3.17 ± 0.07 2.75 ± 0.05 3.17 ± 0.24 3.03 ± 0.07 3.19 ± 0.09 0.104 Hb (g/dL) 8.94 ± 0.49 7.85 ± 0.45 8.32 ± 0.21 8.23 ± 0.20 9.49 ± 0.50 0.070 PCV (%) 35.28 ± 0.31 32.33 ± 0.29 Φ 33.57 ± 0.35 Ω 34.21 ± 0.58 Ω 35.34 ± 0.33 Ω 0.000 MCV (μm 3 ) 109.48 ± 1.56 116.60 ± 2.50 106.63 ± 7.90 111.91 ± 2.43 109.99 ± 2.14 0.522 MCH (pg) 27.67 ± 0.98 28.24 ± 1.35 26.32 ± 1.64 26.92 ± 0.85 29.42 ± 0.81 0.417 MCHC (%) 25.00 ± 1.16 24.02 ± 1.31 24.54 ± 0.64 23.80 ± 0.27 26.55 ± 1.19 0.353 Platelet count ( × 10 3 /mm 3 ) 216.53 ± 5.40 205.92 ± 2.68 211.61 ± 4.87 214.48 ± 1.52 222.02 ± 5.48 0.160 WBCs count ( × 10 3 /mm 3 ) 11.67 ± 0.21 10.74 ± 0.20 11.24 ± 0.28 11.63 ± 0.25 11.50 ± 0.39 0.160 Large lymphocytes (%) 57.77 ± 0.23 54.45 ± 0.70 Φ 55.69 ± 0.62 56.89 ± 0.74 Ω 57.10 ± 0.51 Ω 0.010 Small lymphocytes (%) 24.20 ± 0.32 21.53 ± 0.25 Φ 23.02 ± 0.47 Ω 23.89 ± 0.29 Ω 24.75 ± 0.35 Ω 0.000 Neutrophils (%) 11.11 ± 0.26 13.86 ± 0.57 Φ 13.12 ± 0.47 12.06 ± 0.70 Ω 11.27 ± 0.29 Ω 0.005 Monocytes (%) 2.96 ± 0.01 1.98 ± 0.40 2.23 ± 0.25 2.47 ± 0.29 2.69 ± 0.24 0.144 Eosinophils (%) 2.72 ± 0.25 7.18 ± 0.47 Φ 4.70 ± 0.85 Ω 3.20 ± 0.24 Ω 2.20 ± 0.24 Ω 0.000 RBCs: red blood cells; Hb: hemoglobin; PCV: packed cell volume; MCV: mean corpuscular volume; MCH: mean corpuscular hemoglobin; MCHC: mean corpuscular hemoglobin concentration; WBCs: white blood cells. Results are expressed as the mean ± SEM of 6 fish per group (One-way ANOVA followed by Duncan post-test). Φ Significant difference at p < 0.05 between control and pyrogallol groups; Ω Significant difference at p < 0.05 between pyrogallol and microalgae groups. Section title: Morphological erythrocytic alterations and nuclear abnormalities Educational score: 4.131073951721191 Domain: biomedical Document type: Study Language: en In the control group, RBCs displayed a typical shape with a nucleus positioned centrally. However, smears from the pyrogallol group exhibited poikilocytosis in RBCs after the exposure periods. Various morphological changes were evident, including tear-drop cells, spinocytes, crenated cells, acanthocytes, eccentric nuclei, kidney-shaped cells, and schistocytes . The frequency of cell modifications and nuclear irregularities in RBCs notably rose in the intoxicated group in comparison to the control group . Fig. 1 The percentage of cell alterations and nuclear abnormalities in RBCs of pyrogallol-intoxicated C. gariepinus after 15 days of treatment with S. platensis (SP), C. vulgaris (CV), and M. oleifera (MO). Results are expressed as the mean ± SEM of 6 fish per group (One-way ANOVA followed by Duncan post-test). Φ Significant difference at p < 0.05 between control and pyrogallol groups; Ω Significant difference at p < 0.05 between pyrogallol and microalgae groups. Fig. 1 Fig. 2 Represented blood smears in C. gariepinus showing (a) the normal erythrocytes, (b and c) the deformed ones after exposure to 10 mg/L pyrogallol, (d) the deformed ones after exposure to 10 mg/L of pyrogallol + S. platensis (20 g/kg diet), (e) 10 mg/L of pyrogallol + C. vulgaris (50 g/kg diet) and (f) 10 mg/L of pyrogallol + M. oleifera (5 g/kg diet); Tr, tear-drop cell; Sp, spinocyte; Cr, crenated cell; Ac, acanthocyte; Eco, ecocentric nucleus; Bn, Bionucleus; Kn, kidney shape and Sh, schistocytic (H & E stain, scale bar: 100 μm). Fig. 2 Section title: Morphological erythrocytic alterations and nuclear abnormalities Educational score: 4.084162712097168 Domain: biomedical Document type: Study Language: en Upon a 15-day exposure to 10 m/L of pyrogallol alone, the observed alteration percentages were 47.5 ± 3.59 % for cell alterations and 9 ± 1.41 % for nuclear abnormalities compared to the control group. Nevertheless, following the same exposure duration, the observed alteration percentages were 13.7 ± 0.82 %, 13.1 ± 0.73 %, and 14.2 ± 1.54 % for cell alterations, and 4 ± 0.81 %, 4.1 ± 0.8 %, and 4.5 ± 0.7 % for nuclear abnormalities when exposed to 10 mg/L pyrogallol + S. platensis , 10 mg/L of pyrogallol + C. vulgar is, and 10 mg/L of pyrogallol + M. oleifera , respectively. Thus, the supplementation of pyrogallol-exposed groups with S. platensis , C. vulgar is, and M. oleifera showed a significant reduction in cellular and nuclear abnormalities. Section title: Hepatic and renal damage biomarkers Educational score: 4.207009315490723 Domain: biomedical Document type: Study Language: en The pyrogallol-intoxicated groups showed a significant increase in blood glucose levels compared to the control. However, treatments with C. vulgar is and M. oleifera significantly reduced these elevated glucose levels, while SP did not yield significant changes. Pyrogallol-exposed fish displayed increased serum creatinine and TC levels. Yet, all studied microalgae significantly decreased these elevated levels. M. oleifera exhibited superior efficacy compared to S. platensis in reducing serum creatinine and TC levels. Remarkably, there were no significant alterations in serum AST, ALT, and TP between the groups ( Table 2 ). Table 2 Effects of the studied microalgae on hepatic and renal damage biomarkers in pyrogallol intoxicated- C. gariepinus. Table 2 Parameter Group Control Pyrogallol Pyrogallol + S. platensis Pyrogallol + C. vulgaris Pyrogallol + M. oleifera P value AST activity (μ/l) 34.89 ± 1.06 35.33 ± 0.78 34.80 ± 0.89 34.41 ± 0.88 32.58 ± 0.73 0.253 ALT activity (μ/l) 17.23 ± 0.53 18.09 ± 0.54 17.48 ± 0.44 17.14 ± 0.51 16.57 ± 0.53 0.364 ALP activity (μ/l) 47.40 ± 1.70 43.31 ± 1.36 45.29 ± 1.48 46.07 ± 2.11 44.58 ± 1.74 0.532 Glucose level (mg/dl) 70.22 ± 1.61 78.61 ± 0.45 Φ 74.18 ± 2.15 72.91 ± 1.68 Ω 72.39 ± 1.01 Ω 0.016 TP level (mg/dl) 3.98 ± 0.16 4.56 ± 0.28 4.33 ± 0.20 4.21 ± 0.23 4.17 ± 0.17 0.441 TC level (mg/dl) 210.09 ± 0.63 223.25 ± 3.30 Φ 215.57 ± 1.42 Ω 212.75 ± 1.62 Ω 208.29 ± 1.89 Ω 0.000 Creatinine level (mg/dl) 0.36 ± 0.01 0.46 ± 0.02 Φ 0.39 ± 0.01 Ω 0.38 ± 0.01 Ω 0.35 ± 0.01 Ω 0.000 UA level (mg/dl) 22.84 ± 0.25 23.27 ± 0.37 22.67 ± 0.12 22.73 ± 0.23 22.03 ± 0.21 Ω 0.043 AST: aspartate aminotransferase; ALT: alanine transaminase; ALP: alkaline phosphatase; TP: total protein; TC: total cholesterol; UA: uric acid. Results are expressed as the mean ± SEM of 6 fish per group (One-way ANOVA followed by Duncan post-test). Φ Significant difference at p < 0.05 between control and pyrogallol groups; Ω Significant difference at p < 0.05 between pyrogallol and microalgae groups. Section title: Oxidative stress parameters and pro-inflammatory interleukin-6 Educational score: 4.160706996917725 Domain: biomedical Document type: Study Language: en Pyrogallol exposure resulted in a significant reduction in serum SOD activity and TAC, along with an elevation in serum MDA levels. Diets enriched with C. vulgaris and M. oleifera significantly normalized these parameters, while S. platensis did not produce any significant changes. All microalgae failed to improve TAC except for M. oleifera , which significantly increased it. MDA levels returned to the control level equally and significantly. IL-6 levels did not show significant changes between any of the groups ( Table 3 ). Table 3 Effects of the studied microalgae on serum oxidative stress parameters and pro-inflammatory interleukin-6 in pyrogallol intoxicated- C. gariepinus. Table 3 Parameter Group Control Pyrogallol Pyrogallol + S. platensis Pyrogallol + C. vulgaris Pyrogallol + M. oleifera P value SOD activity (U/ml) 2.68 ± 0.06 1.91 ± 0.10 Φ 2.23 ± 0.13 2.63 ± 0.19 Ω 2.67 ± 0.05 Ω 0.000 TAC (nmol/l) 56.86 ± 4.28 42.65 ± 1.16 Φ 43.76 ± 0.40 48.61 ± 3.10 50.40 ± 1.20 0.007 MDA level (nmol/ml) 14.94 ± 1.28 30.57 ± 2.60 Φ 17.97 ± 0.39 Ω 16.59 ± 0.95 Ω 16.87 ± 1.37 Ω 0.000 IL-6 level (pg/ml) 51.15 ± 0.34 53.42 ± 0.23 Φ 55.77 ± 0.47 58.04 ± 1.75 55.72 ± 2.91 0.060 SOD: superoxide dismutase; TAC: total antioxidant capacity; MDA: malondialdehyde; IL-6: interleukin-6. Results are expressed as the mean ± SEM of 6 fish per group (One-way ANOVA followed by Duncan post-test). Φ Significant difference at p < 0.05 between control and pyrogallol groups; Ω Significant difference at p < 0.05 between pyrogallol and microalgae groups. Section title: Histopathological and histochemical findings Educational score: 4.223241329193115 Domain: biomedical Document type: Study Language: en Liver sections stained with Hematoxylin and Eosin from the control group showed a normal structure. The hepatocytes appeared polygonal with unstained cytoplasm and centrally or eccentrically located rounded vesicular nuclei. Cords of hepatocytes radiated from central veins with blood sinusoids located between these cords. In the pyrogallol group, hepatic tissue exhibited numerous necrotic areas, pycnotic nuclei of hepatocytes, and congested dilated blood sinusoids . Inflammatory cell infiltration was observed. Mild improvement was detected in liver sections from the pyrogallol + S. platensis group . There was congestion of central veins and blood sinusoids, and pycnotic nuclei of some hepatocytes were noted. Necrotic areas were dispersed throughout the hepatic tissue. The liver of the pyrogallol + C. vulgaris group showed moderate improvement compared to the pyrogallol group, with some hepatocytes resembling those of the control group. Necrotic areas were still clearly observed. Marked improvement was observed in the hepatic tissue of the pyrogallol + M. oleifera group . The hepatocytes closely resembled those of the control group, although some blood sinusoids remained congested. Pigments were observed near the central vein. The histopathological scoring of lesions observed in the hepatic tissue is represented in Table 4 . Fig. 3 Photomicrographs of liver sections in C. gariepinus stained by H&E (bars = 50 μm) showing: (a) control group, (b) Pyrogallol group, (c) Pyrogallol + S. platensis , (d) Pyrogallol + C. vulgaris and (e) Pyrogallol + M. oleifera ; CV, central vein ; Δ , rounded vesicular nucleus of hepatocyte; ▲, congested blood sinusoid; ↑ , pyknotic nucleus; black asterisk , necrotic area; yellow arrow , inflammatory cells infiltration, red asterisk , congested central vein and red arrow , pigments. Fig. 3 Table 4 Scoring of histopathological lesions in the liver and kidney of the examined groups. Table 4 Lesions Groups Control Pyrogallol Pyrogallol + S. platensis Pyrogallol + C. vulgaris Pyrogallol + M. oleifera Liver Hepatocytes with pycnotic nuclei – +++ +++ + ++ Necrotic areas – +++ ++ ++ + Inflammatory cells infiltration – +++ ++ + + Congestion of blood vessels – ++ +++ + + Dilated blood sinusoids – ++ ++ + + Hemorrhage – + + – – Kidneys Bowman's capsule thickening – +++ +++ + – Glomeruli shrinkage – ++ + + – Glomerular tuft vacuolar degeneration + ++ + – + Complete degeneration of renal tubules – +++ ++ + – Separation of tubular cells from basement membrane + +++ ++ + + Pyknotic nuclei of renal tubular cells + +++ ++ + + Vacuolated renal tubular cells – +++ ++ + + Inflammatory cells infiltration + ++ ++ + + Melanomacrophage centers + +++ ++ ++ ++ Hematopoietic tissue + +++ +++ ++ + (−) Absent, (+) Slight (<25 %), (++) Moderate (from 25 to 50 %), and (+++) Severe lesion (>50 %). Section title: Histopathological and histochemical findings Educational score: 4.101480960845947 Domain: biomedical Document type: Study Language: en The liver sections stained with PAS staining revealed the glycogen content in the hepatic tissue . The magenta color observed in the liver sections from the control group indicated a normal amount of glycogen . A significant reduction in glycogen levels was observed in the pyrogallol-treated group , which was statistically significant compared to the control group . Glycogen content increased significantly in the pyrogallol + C. vulgaris and pyrogallol + M. oleifera groups compared to the pyrogallol group, but not significantly in the pyrogallol + S. platensis group. There were no significant differences in glycogen content among the three treated groups (pyrogallol + S. platensis , pyrogallol + C. vulgaris , and pyrogallol + M. oleifera ) and the control group . Fig. 4 Examination of liver glycogen in C. gariepinus . (a – e) : photomicrographs of liver sections stained by PAS stain (bars = 50 μm) showing: (a) control group with normal glycogen content as represented by magenta color, (b) Pyrogallol group, (c) Pyrogallol + S. platensis (SP), (d) Pyrogallol + C. vulgaris (CV), and (e) Pyrogallol + M. oleifera (MO). (f) liver glycogen in sections from all experimental groups. Bars represent means ± SE. Different letters indicate significant differences among treatments (p < 0.5). Fig. 4 Section title: Histopathological and histochemical findings Educational score: 4.164851665496826 Domain: biomedical Document type: Study Language: en The kidney of the control group showed Malpighian corpuscles with Bowman's space separating glomerular tufts and Bowman's capsule. Renal tubules were composed of cells with rounded vesicular nuclei. Hematopoietic tissue appeared normal in its content within the renal tissue, and melanomacrophages were also detected. In the Pyrogallol group, the kidney exhibited significant deterioration in renal tissue . There was thickening of Bowman's capsule around the Malpighian corpuscles, and the glomeruli showed vacuolar degeneration. Renal tubules had vacuolated cytoplasm and pyknotic nuclei, with necrotic areas also present. The hematopoietic tissue was excessively represented with densely packed components, and melanomacrophages were widespread throughout the renal tissue. Fig. 5 Photomicrographs of kidney sections in C. gariepinus stained by H&E (bars = 50 μm) showing: (a) control group, (b) Pyrogallol group, (c) Pyrogallol + S. platensis , (d) Pyrogallol + C. vulgaris and (e) Pyrogallol + M. oleifera ; Δ, Bowman's capsule; ▲, glomerulus; ↑ , renal tubular cell; yellow arrow , melanomacrophage; red asterisk , hematopoietic tissue; black asterisk , necrotic area; green arrow , thickening of Bowman's capsule; yellow arrowhead , glomerular vacuolar degeneration; blue arrow , vacuolated renal tubular cell with pyknotic nucleus; red arrow , shrunken glomerulus and orange arrow , separation of renal tubular cells from basement membrane. Fig. 5 Section title: Histopathological and histochemical findings Educational score: 3.9810314178466797 Domain: biomedical Document type: Study Language: en In the kidney sections from the pyrogallol + S. platensis group , mild improvement was observed compared to the pyrogallol group. Shrunken glomeruli of Malpighian corpuscles were observed, and renal tubular cells showed separation from their underlying cell membranes. Hematopoietic tissue was excessively present, and necrotic areas and melanomacrophages were detected. Section title: Histopathological and histochemical findings Educational score: 3.9360413551330566 Domain: biomedical Document type: Study Language: en In pyrogallol + C. vulgaris kidney sections , mild to moderate improvement in renal tissue was observed. Shrunken glomeruli of Malpighian corpuscles were observed, along with vacuolated renal tubular cells with pyknotic nuclei. Some necrotic areas and melanomacrophages were also present. Section title: Histopathological and histochemical findings Educational score: 3.9770028591156006 Domain: biomedical Document type: Study Language: en Moderate improvement was detected in the renal tissue of the pyrogallol + M. oleifera group . Normal Malpighian corpuscles and vesicular rounded nuclei of renal tubular cells were observed. Separation of some renal tubular cells from their basement membranes was detected, along with the presence of hematopoietic tissue and melanomacrophages. Section title: Histopathological and histochemical findings Educational score: 2.4139809608459473 Domain: biomedical Document type: Study Language: en Histopathological scoring for the above-mentioned lesions is represented in Table 3 . Section title: Histopathological and histochemical findings Educational score: 4.109292030334473 Domain: biomedical Document type: Study Language: en Staining kidney sections with PAS staining revealed the polysaccharide content in the renal tissue . The magenta color observed in the glomeruli of Bowman's capsule, basement membranes, and brush borders of renal tubules from the control group indicated a normal amount . A marked depletion of polysaccharide content was detected in the pyrogallol group , and this decrease was statistically significant compared to the control group . The number of polysaccharides increased significantly in the three treated groups (pyrogallol + S. platensis , pyrogallol + C. vulgaris , and pyrogallol + M. oleifera ) compared to the pyrogallol group . There were no significant differences in polysaccharide content between the control group and the pyrogallol + C. vulgaris and pyrogallol + M. oleifera groups. Fig. 6 Examination of polysaccharides of kidney sections in C. gariepinus . (a – e) : photomicrographs of kidney sections stained by PAS stain (bars = 50 μm) showing: (a) control group with normal polysaccharides content as represented by magenta color in glomeruli, basement membranes and brush borders of renal tubules, (b) Pyrogallol group, (c) Pyrogallol + S. platensis (SP), (d) Pyrogallol + C. vulgaris (CV) and (e) Pyrogallol + M. oleifera (MO). (f): kidney polysaccharides of sections from all experimental groups. Bars represent means ± SE. Different letters indicate significant differences among treatments (p < 0.5). Fig. 6 Section title: Discussion Educational score: 4.07888126373291 Domain: biomedical Document type: Study Language: en As reported earlier , C. gariepinus encountered pyrogallol induced a marked drop in PCV which could be due to hemodilution, osmoregulatory issues, or kidney function disruption . The notable enhancement in PCV observed in our study, resulting from the dietary incorporation of microalgae, mirrors findings in O. niloticus supplemented with C. vulgaris after deltamethrin-induced hematotoxicity , as well as in C. gariepinus supplemented with S. platensis after chlorpyrifos exposure , and O. niloticus supplemented with M. oleifera after chlorpyrifos exposure . Section title: Discussion Educational score: 4.283696174621582 Domain: biomedical Document type: Study Language: en The marked reduction in lymphocytic populations following pyrogallol exposure indicates weakness of immuno-potency, as documented earlier . The decline in circulating lymphocytes could occur due to stress-triggered cell death in lymphocytes , heightened oxidative injury, and suppressed antioxidant shield . The expansion of lymphocytic clones is crucial for phagocytosis and immune responses against xenobiotic agents as seen in our microalgae-supplemented groups. The rise in lymphocytic count following feeding with microalgae-enriched diet confirms their immune-boosting impacts and stress-alleviating features of C. vulgar is . The immune-related impacts of dietary S. platensis could be linked to its diverse bioactive components like phycocyanin, phycobilins, xanthophylls, and allophycocyanin . The immune enhancement in C. gariepinus fed on the M. oleifera -enriched additive may be due to a variety of phytochemical ingredients . These include the rich content of polyphenolic compounds, volatile oils, and vitamins known for their immune-boosting properties . A previous study on the hematotoxic effects of pyrogallol in C. gariepinus triggered neutrophilia and eosinophilia . On the contrary, the studied microalgae succeeded in counteracting these abnormalities by enhancing the expression of anti-inflammatory mediators and suppressing the expression of pro-inflammatory mediators [ , , ]. Section title: Discussion Educational score: 4.646939277648926 Domain: biomedical Document type: Study Language: en The potential of pyrogallol to oxidize the sulfhydryl moiety located on fatty acid chains present within the cell membrane might be the underlying reason for the poikilocytosis observed in this study. In addition, excessive generation of reactive oxygen species heightens lipid peroxidation, hampers intracellular protein function, and causes DNA harm. This process can impact mitochondrial oxidative phosphorylation, prompting the discharge of numerous inflammatory substances and ultimately resulting in execution of cell suicide . The cytoprotective capability of microalgae aligns with findings observed in O. niloticus challenged with fipronil , largemouth bass ( Micropterus salmoides ) , and rats experiencing cobalt-induced apoptosis . S. platenesis mitigates the genotoxic effects by alleviating the chromosomal structural aberrations and DNA mutations due to its exceptional polysaccharides, which boost DNA repairing enzymes . Carotenoids, the active phytoconstituents in S. platenesis , encourage the activity of redox stabilizers and detoxifying enzymes, promoting cell proliferation . C. vulgar is demonstrates an anti-apoptotic impact by boosting the expression of anti-apoptotic genes, while reducing the expression of pro-apoptotic genes in M. salmoides . It increased the expression of peroxisome proliferator-activated receptor α, reduced activator protein 1 gene expression in the liver, and restored chromosomal stability and mitotic index of bone marrow cells in rats subjected to gibberellic acid-associated cytogenotoxicity . Quercetin found in M. oleifera lessens micronucleus occurrences and chromosomal abnormalities by directly interacting with xanthine oxidase and nitric oxide synthase, thereby decreasing the oxidative burden inside the cellular milieu . Kaempferol, a polyphenolic agent in M. oleifera , boosts b cell lymphoma-2 expression, consequently suppressing the presence of cell suicidal indicators like caspase-3 and poly (ADP-ribose) polymerase . Section title: Discussion Educational score: 3.596344232559204 Domain: biomedical Document type: Study Language: en Given the dose and duration employed in our study, the oxidative infliction and inflammatory damage in our model might not have been intense enough to disrupt the cellular membranes or lead to the discharge of hepatic enzymes into the circulating blood. Further research is therefore needed to explore the dose-dependent effects of pyrogallol on liver function. Section title: Discussion Educational score: 4.452418327331543 Domain: biomedical Document type: Study Language: en The elevated glucose levels noticed in pyrogallol-exposed fish might result from cortisol-induced hyperglycemia . This observation is supported by the depletion of hepatic and renal glycogen reserves, evident in histochemical analysis, primarily attributed to increased mRNA expression of genes encoding enzymes of glycogenolysis . The hypoglycemic activity of the studied microalgae is similar to that occurred in rainbow trout ( Oncorhynchus mykiss ) , crucian carp ( Carassius auratus ) , and O. niloticus . The improvement in insulin sensitivity , glycogenesis, glycolysis , inhibition of gluconeogenesis, and activation of insulin receptors may contribute to the antihyperglycemic effect of S. platensis . C. vulgar is exhibits analogous action by reducing insulin resistance and safeguarding beta-cell function from peroxidative insult , as well as inhibiting pancreatic alpha-amylase . Studies have demonstrated that M. oleifera can improve insulin resistance through multiple mechanisms. It activates the phosphoinositide 3-kinase/AKT and 5′ AMP-activated protein kinase pathways, enhances oxidative metabolism through the nicotinamide adenine dinucleotide-related deacetylase-peroxisome proliferator–activated receptor α pathway, and hinders fatty acid peroxidation . Section title: Discussion Educational score: 4.403873443603516 Domain: biomedical Document type: Study Language: en The hypercholesterolemia following pyrogallol intoxication is aligned with . The increase in TC levels might stem from alterations in liver cell permeability and disturbances in lipid metabolism, potentially associated with the buildup of the contaminants in the liver . Consistent with other research, microalgae exhibited beneficial effects on lipid balance [ , , ]. The hypolipidemic effects of S. platensis are thought to stem from its key components like linoleic acid, gamma linolenic acid, phycocyanin, phenolic compounds, and niacin . S. platensis demonstrates its hypolipidemic effects by activating lecithin cholesterol acyltransferase, a crucial element in the reverse cholesterol transport process, and by hindering 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, an enzyme vital for the production of cholesterol . C. vulgar is is an abundant provider of omega-3 polyunsaturated fatty acids which directly hinder acetyl-CoA carboxylases and reduce the mRNA expression of sterol regulatory element–binding proteins , thereby decreasing the production and function of lipogenic enzymes. Lipid-lowering properties of M. oleifera might be linked to its chemical profile, containing alkaloids, flavonoids, saponins, and cardiac glycosides . Saponins have the potential to lower cholesterol levels by either adhering to cholesterol in the intestines, thereby impeding its absorption, or by attaching to bile acids. This interaction may reduce the recycling of bile acids between the intestines and the liver, leading to their increased excretion in feces . Section title: Discussion Educational score: 4.544440269470215 Domain: biomedical Document type: Study Language: en Although the oxidant and antioxidant biomarkers were measured in the serum, they reflect redox disturbances that may adversely impact the hepatic and renal structures [ , , ]. The redox alterations induced by pyrogallol, marked by increased serum MDA levels and decreased serum TAC and SOD activity, align with the findings of Hamed et al. ). Like other chemotoxicants, this can be explained by the overproduction of reactive oxygen species , along with the downregulation of antioxidant gene expression , redox-linked transcription factors, and antioxidant responsive mediators . The oxidative stress caused by pyrogallol intoxication may be associated with the histological lesions and cytological modifications . The ability of microalgae to counteract the redox abnormalities induced by pyrogallol is comparable to the effects observed in O. niloticus exposed to imidacloprid , deltamethrin , and oxyfluorfen toxicity. The presence of bioactive components namely β-carotene, C-phycocyanin , γ-linolenic acid and α-tocopherol could underlie the marked antioxidant ability of S. platenesis against pyrogallol-induced oxidative injuries. These compounds, whether independently or synergistically, neutralize free radicals like, alkoxyl, peroxyl, and hydroxyl radicals . Additionally, C-phycocyanin can decrease nitrite generation and block lipid peroxidation . The defensive characteristics of C. vulgaris against the disruption in antioxidant shield may be related to its carotenoid profile, including β-carotene, lutein, canthaxanthin, and astaxanthin . They are effective in quenching the singlet oxygen and eliminating reactive oxidants . The phenolic constituents in M. oleifera , including kaempferol and quercetin glucosides , along with its total flavonoid content , are responsible for its antioxidant activity. Section title: Discussion Educational score: 4.503724575042725 Domain: biomedical Document type: Study Language: en Increased serum IL-6 levels, inflammatory cell infiltration in liver tissue, along with an elevated count of blood neutrophils and eosinophils, suggest that inflammation may play a significant role in pyrogallol toxicity. In a previous study , pro-inflammatory cytokines, including IL-1 beta and IL-6, were found to be elevated in the serum of C. gariepinus following pyrogallol contamination. This outcome could be attributed to the stimulation of the inflammatory cascade through the upregulation of the NF-κB signaling pathway . Pyrogallol depletes dissolved oxygen levels in water tanks . The depletion of oxygen in the ecosystem has been associated with increased levels of pro-inflammatory mediators in Chilean salmon ( Oncorhynchus kisutch ) . Similar to other reports , inflammatory cell accumulation was observed in the intestinal and muscular tissues of pyrogallol-intoxicated C. gariepinus. This finding might be due to the release of chemoattractants, which act as mediators for inflammatory cellular recruitment. IL-6 plays a role in neutrophil migration by inducing the production of chemokines, such as IL-8 and monocyte chemoattractant protein-1, and by triggering the expression of adhesion molecules on endothelial cells . Following the trafficking of neutrophils to the challenge site, they release chemokines to stimulate tissue-resident cells and recruit more leukocytes to the injured area, thereby intensifying inflammation . Inflammatory response can lead to a marked increase in eosinophil count . Eosinophils release inflammatory mediators through degranulation and function as antigen-presenting cells during inflammation . A previous study on the hematotoxic effects of pyrogallol in C. gariepinus reported neutrophilia and eosinophilia . Conversely, the studied microalgae succeeded in counteracting these abnormalities by enhancing the expression of anti-inflammatory mediators and suppressing the expression of pro-inflammatory mediators . Section title: Discussion Educational score: 4.157662391662598 Domain: biomedical Document type: Study Language: en Free radicals have the potential to harm the renal cells directly, activate intracellular signaling routes, or prompt systemic reactions that result in kidney damage . In a previous cited article, pyrogallol-treated C. gariepinus displayed extensive damage to the tubular structure, including complete splitting of the tubular epithelium with the loss of the basement membrane and various changes in cell nuclei. Additionally, the intertubular hematopoietic tissues exhibited higher content of RBCs alongside increased pigmented cell counts . In parallel with the histopathological disruptions in renal tissues and in accordance with previous research , serum creatinine levels markedly raised in the pyrogallol group. Estimation of creatinine can be applied to identify renal filtration rate and as an evaluation for renal inadequacy . The increased creatinine can be ascribed to the reducing effect of pyrogallol on glomerular filtration or increase in protein breakdown rates . Section title: Discussion Educational score: 4.630763053894043 Domain: biomedical Document type: Study Language: en Xenobiotics are recognized for causing liver damage through generating metabolic intermediates that can interact with cellular elements resulting in oxidative injury, antioxidants exhaustion, lipid peroxidation, and heightened membrane penetrability . The cellular alterations in the liver of pyrogallol-exposed C. gariepinus mirror those documented previously , and these changes are linked to the capacity of pyrogallol to stimulate pro-inflammatory cytokines which play important role in hepatic parenchymal cell damage . At the cellular level, cytoplasmic vacuoles are formed from elements of the endoplasmic reticulum or endosomal-lysosomal organelles due to cellular osmotic disturbance and exhaustion of ATP reserve . The histopathological deteriorations observed in the kidney of fish exposed to pyrogallol resemble those reported in a previous study . Extensive necrosis in hepatic tissue and the degeneration of renal tubules and glomerular tuft are commonly documented during exposure to various toxicants and may be mediated by the disruption in cytoskeletal elements . Pyknosis, the irreversible condensation of chromatin within a cell's nucleus, serves as an indicator of cellular apoptosis . An elevated occurrence of melanomacrophage aggregates in the kidney signifies notable tissue lesions and elevated immune response . The observed histological enhancements from the investigated microalgae are consistent with findings previously documented in studies by Refs. . The reduction in quantities of MMCs in microalgae-supplemented groups could be due to their immunostimulatory properties . The hematopoietic system in fish exhibits significant homeostatic potential, typically compensating for cell loss through the initiation of mitotic replication . The cytoprotective effect of S. platensis arises from its ability to up-regulate the expression of proliferating cell nuclear antigen which is responsible for DNA replication and regulation of cell cycle . In C. gariepinus , C. vulgar is counteracted the hepatorenal toxicity induced by microplastic particles by restoring the carbohydrate content in the microvilli and underlying membranes of kidney tubules and glomeruli, as well as within the cytoplasm of liver cells . C. vulgar is possesses chlorella growth mediators, promoting cellular multiplication and tissue regeneration. It also activates the immunity to assist in clearing away deceased cells . M. oleifera prompted the expression of PCNA and Ki-67 in the renal tissues of rats experiencing melamine-induced nephrotoxicity, indicating an improved capacity for cellular multiplication and renewal . Section title: Conclusions Educational score: 4.229683876037598 Domain: biomedical Document type: Study Language: en Based on our results, exposure of C. gariepinus to pyrogallol led to alterations in blood granulocytes percent, erythrocytic cellular and nuclear features, and the redox defensive mechanism. Pyrogallol did not induce hepato-renal dysfunction and microalgae intervention did not enhance hepato-renal function. Based on the dose and duration used in our study, the oxidative burden and inflammatory effects in our experimental model may not have reached a threshold sufficient to disrupt the cellular membrane and cause the leakage of hepatic metabolizing enzymes into the bloodstream. Nevertheless, pyrogallol caused elevated serum glucose, TC, and creatinine levels, indicating metabolic deterioration confirmed by cytopathological lesions. Conversely, the investigated microalgae showed promise as potential remedies for mitigating these abnormalities. In this regard, M. oleifera was the most effective, followed by C. vulgaris , with S. platensis being the least effective. Consequently, incorporating these nutritional supplements into the diet could be pivotal in the aquaculture sector to alleviate the impact of environmental pollutants. However, dose-dependent studies are strongly recommended to thoroughly investigate the toxicological effects of pyrogallol on hepato-renal function and the potential benefits of microalgae. Section title: CRediT authorship contribution statement Educational score: 0.9642115831375122 Domain: other Document type: Other Language: en Mohamed Hamed: Writing – review & editing, Writing – original draft, Methodology, Investigation, Conceptualization. Nasser S. Abou Khalil: Writing – review & editing, Writing – original draft, Methodology, Investigation. Alshaimaa A.I. Alghriany: Writing – review & editing, Writing – original draft, Funding acquisition, Formal analysis. Alaa El-Din H. Sayed: Writing – review & editing, Writing – original draft, Methodology, Investigation, Conceptualization. Section title: Data availability statement Educational score: 0.7444794774055481 Domain: biomedical Document type: Other Language: en All relevant raw data will be freely available from the authors. Section title: Funding statement Educational score: 0.9412661194801331 Domain: other Document type: Other Language: en This research received no external funding. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Study | biomedical | en | 0.999998 |
PMC11699243 | Section title: Introduction Educational score: 1.0989097356796265 Domain: other Document type: Other Language: en Investors opt for safe-haven assets to safeguard the value of their assets during economic, policy, and other naturally occurring uncertainties. Active search for safer alternatives and extreme fear of losing value during uncertain times negatively impact investor risk aversion and increase market trading, risk premium, and overall uncertainty [ , , ]. Hence, switching assets and rebalancing portfolios due to uncertainties find their roots in rational expectations and sentimental exuberance. Rational expectations to maximize utility, investors used to shift to conventional safe-haven assets that included precious metals, different commodities, and even currencies. Desperate investors driven by fear may inadvertently choose riskier assets, exacerbating volatility and portfolio rebalancing costs . Section title: Introduction Educational score: 1.3047624826431274 Domain: other Document type: Study Language: en In the recent years, green and ethical assets have experienced significant growth. According to Bloomberg, the worldwide ESG (Environment, Social, & Governance) asset market size is projected to reach US $53 trillion by2025. 1 PwC estimates institutional investors’ interest growth for ESG investment to soar at 84 % to reach $33.9 trillion by2026. 2 Aside from social responsibility and growing market size, investments in ethical assets have grown over the years as they have outperformed other asset classes from different dimensions. Investors pay a premium for GBs . Green bonds may offer an efficient hedge against short-term market uncertainty . The clean energy index may also serve as an efficient hedge and safe haven amid a crisis . Moreover, EPU significantly influences GBI in the long run, with positive and negative effects across most quantiles, but opposite effects are only significant in higher quantiles . However, Positive and negative shocks to GPR have an adverse short-term impact on GB returns. In the long term, GB returns are positively impacted by negative shocks in GPR and negatively affected by positive shocks in GPR . Previous studies have limited literature on safe properties in various asset classes, with a focus on green assets during the 2008 financial crisis and the COVID-19 pandemic. This study examines the safe haven properties of seven assets, including ethical asset indices and a conventional stock index, during geopolitical crises, economic policy uncertainty, and stock market volatility. It allows investors to match their portfolios with their values and gives stakeholders the knowledge they need to make wise decisions. Section title: Introduction Educational score: 1.2337414026260376 Domain: other Document type: Study Language: en Despite having profound growth, literature on the safe haven status of the ethical asset class is very inadequate. This study contributes to this gap from three dimensions. Firstly, we consider two types of ethical financial assets: environmental or green ethical assets (SPESG, MSCIESGL, SPGRNB, SPCLN, DJSI) and religious ethical assets (e.g., Islamic asset class; DJIM). We also add a conventional asset to make a comparison. Secondly, the impact of uncertainty is time- and context-varying. We have considered three types of uncertainties: 1) the geopolitical risk (hereafter, GPR) index; 2) the economic policy uncertainty (EPU) index; and 3) CBOE market volatility (VIX) index. Thirdly, conventional analytical methods often fail to find the hidden dependencies and correlations in asset prices . Hence, we have employed both novel Quantile coherence and Wavelet coherence. to capture the time-varying relation and various market states (bearish, normal, and bullish), respectively, because the literature suggests that the impact of uncertainties on assets varies depending on time and market conditions. Also, we employ extreme shocks from uncertainty factors analysis. Furthermore, we decompose our data into three frequencies, short, medium, and long, to comprehend the time-frequency, time domain and lead-lag associations between risks and seven asset classes, which would help investors to make better forecasting decisions. Section title: Introduction Educational score: 1.0853132009506226 Domain: other Document type: Study Language: en Alongside this, the timeframe considered in this study covers some important global, regional, and economic risk events, including the most recent COVID-19 pandemic. There are several rationales for selecting these assets. First, these assets have been established in the past literature as safe-haven assets, particularly against conventional asset classes, e.g., stocks, precious metals, bonds, etc. Second, these assets have shown a strong potential to withhold uncertainty shocks. The study assumes the potential of these asset classes for investors seeking to build a sustainable portfolio for a low-carbon future. Section title: Introduction Educational score: 1.4349572658538818 Domain: other Document type: Study Language: en Our findings suggest that all seven assets can provide a safe haven against geopolitical risk (GPR) due to the positive or neutral impact of GPR shocks in all markets, frequency (excluding bullish markets with monthly frequency), and time domain. Most observed coherencies between economic policy uncertainty (EPU) and the seven assets are positive at lower quantile levels during monthly frequencies and middle to upper quantile levels during weekly frequencies. These results indicate that the selected assets can help hedge EPU shocks in a range of market regimes. On the other hand, during economic crises and COVID-19 pandemics, most assets, except the S&P Green Bond (SPGRNB) and S&P Global Clean Energy (SPCE) indices, are negatively impacted by EPU. Furthermore, all asset index returns, except SPGRNB, are particularly vulnerable to the movement of the volatility index (VIX). However, in the yearly and monthly frequencies, high stock market volatility (bullish market) has a positive influence on the MSCI World ESG Leaders (MSCIESGL) and SPGRNB. These results indicate their safe-haven capabilities against high stock market volatility regimes. Section title: Introduction Educational score: 1.131933331489563 Domain: other Document type: Other Language: en Clearly, the investors and the fund managers can redesign their portfolios and investment strategies based on these findings. Alternative investment opportunities, demand for safe-haven assets, and a growing climate agenda make these findings important for policymakers as well. While we assume that investors may prefer to switch to some of the green bonds and climate-friendly assets, it is important to recognize the limited availability of these ethical asset classes. Keeping the supply constraints constant, by evaluating both ethical and conventional stock indices against unforeseen vicissitudes in GPR and EPU shocks, portfolio risk managers and investors can balance their capital allocation strategies to win over several risks and market conditions. An ideal portfolio involving green investments will help hedge against GPR and EPU. It is worth noting that ethical assets do not help construct efficient portfolios due to the uncertainties arising from the VIX, particularly in the normal market. We hope that environmentally conscious investors and asset managers act as the vanguard of a new investment standard by combining diverse ethical asset categories in different quantiles and frequencies to diversify the risk and safeguard the value. Moreover, ethical investment research advocates for sustainable, equitable, and responsible finance and business practices. It empowers stakeholders to make well-informed decisions that benefit society and enables investors to align their portfolios with their values, thereby promoting responsible consumption. Companies that prioritize ethics encounter fewer regulatory issues, scandals, and public backlash, ultimately leading to more stable long-term returns. Policymakers have the opportunity to create incentives for ethical investment, thus enhancing market stability and societal welfare. Section title: Introduction Educational score: 1.4101814031600952 Domain: other Document type: Other Language: en We discuss the literature in section two, followed by methodologies in section three, and results in section four. Lastly, section five provides the concluding remarks of this study. Section title: Review of related literature Educational score: 0.9223869442939758 Domain: other Document type: Other Language: en Ethical assets represent an emerging sector within the financial markets. These instruments have gained attraction as they allow investors to support various sustainable initiatives. This also helps them diversify their portfolios and align financial goals with environmental values. Outperformance is highlighted by studies such as those by Reboredo, Ugolini & Tang, Zhang , which indicate that sustainable investments can deliver robust financial returns. However, the pricing of assets presents a complex challenge, as it is influenced by a myriad of factors beyond just environmental impact. Macroeconomic considerations, including geopolitical risks, economic policy uncertainty, and volatility index, play a significant role in the valuation and return of ethics. As such, investors and issuers must navigate these risks to maintain profitability and market stability. Broadstock, Cheng underscore the importance of managing these risks effectively, suggesting that a comprehensive approach to the interplay between environmental and societal factors is crucial. Section title: Global uncertainty and risk factors Educational score: 1.0519684553146362 Domain: other Document type: Other Language: en Over the last ten years, several significant risk factors have impacted global financial markets and economic progress. The war in Ukraine has been the most recent event that has affected the global food supply, energy prices, and the average prices of everyday commodities . A depressing economic growth in the post-COVID-19 pandemic period that was directly impacted by the prolonged uncertainty and destruction of the global value chain has left us with new lows every day in the financial markets. Investors' confidence was negatively affected due to the prolonged uncertainty associated with these adverse events . Other recent key crises include the likes of Russia's annexation of Crimea, the Arab Spring, the global refugee crisis, and Brexit. Such upheavals amplified political and economic instability and global uncertainty while the world continues to advance quickly . Section title: Global uncertainty and risk factors Educational score: 1.068846344947815 Domain: other Document type: Other Language: en The GPR and EPU indexes track specific terms in newspaper coverage to measure geopolitical risk and economic policy uncertainty. They primarily use North American newspapers but have global significance. The GPR and EPU indexes exhibit noticeable spikes during certain events, such as the Russian invasion of Ukraine and the COVID-19 pandemic . The literature on volatility transmission is crucial for modern risk management. The volatility associated with the COVID-19 crisis is significant for both risk and asset management. It is essential to assess whether the risks posed by this crisis differ from those of previous crises. The VIX has emerged as the primary indicator of risk volatility in the financial sector . Climate change and environmental degradation are considered global risk events. The profound impact that poor quality of the environment has on every aspect of human life is being emphasized by the governments and financial market authorities. Consequently, we have witnessed several key changes to how corporations can consume natural resources to achieve net zero and other sustainable growth agendas. For instance, the United Kingdom and China are set to achieve net zero initiatives by the year2050 3 and 2060, respectively. The sustainability agenda has set forth dos and don'ts that are part of the investor screening for choosing a new investment . Since climate factors are global risk factors, investors generally have a positive perception of the stability and performance of these assets in the financial markets. Therefore, ethical assets are generally considered safe. Section title: Global uncertainty and risk factors Educational score: 0.9736523032188416 Domain: other Document type: Other Language: en Geopolitical risks (GPR) are vital factors in investment decisions that impact (stock) market volatility and carry significant economic consequences . The high geopolitical risk reduces trading activity, lowers stock returns, and causes capital plight off the developing economies into the economies that enjoy less uncertainty. Baker stipulate that innovations in EPU anticipate decreases in investment, production, and employment. High volatility in the stock market and a lower drive for investment are sensitive to uncertainty in policy. EPU has been the focal point of a growing strand of literature . These studies generally focus on the impact of uncertainties on economic outputs and asset prices. Section title: Global uncertainty and risk factors Educational score: 1.0758699178695679 Domain: other Document type: Other Language: en Market-based uncertainty arises from financial market volatility, which is generally measured using the VIX index introduced by the Chicago Board Options Exchange (CBOE). The VIX is a substitute for corporate stock market risks and a measure of market uncertainty that fits best with developed markets and industries. The VIX index helps understand market liquidity and depth, which help shape investment decisions . Alongside, volatility indexes also incorporate information on future volatility and are used as a proxy for indicating market sentiment. Literature using VIX is on the rise that looks into how market volatility influences market trading and economic outputs . Section title: Ethical and safe-haven assets Educational score: 1.0605193376541138 Domain: other Document type: Other Language: en Environment, Social, and Governance (ESG) assets have experienced considerable performance improvements in recent decades. Corporations report their ESG engagement not only because of regulatory pressure but also to protect their reputation among competitors and consumers. Investors and consumers take ESG as the ‘right thing to do’ that helps preserve the global climate. Therefore, assets engaging with ESG or being categorized as ESG assets generally experienced lower perceived risk [ , , ]. On similar grounds, these assets also help diversify investment risk. Innovations in line with sustainability gave birth to a new breed of financial assets, e.g., GBs and clean energy. As the market demand grows, countries find it crucial to introduce green bond legal frameworks that incentivize issuers (borrowers) with fiscal benefits owing to their contributions to global environmental issues . Preference for a safer world motivates investors to buy and hold on to these bonds while the borrowers are pledged to invest the proceeds in projects that uphold environmental protection and sustainable climate safety. Consequently, 1) investors go beyond a simple risk-return matrix while buying these assets, 2) they rely on their belief and values-system to invest in these ventures, and 3) they replace other risky assets with these ethical assets at times of crisis. Section title: Ethical and safe-haven assets Educational score: 1.040128469467163 Domain: other Document type: Other Language: en Higher demand pays the bill. A stiff demand shift for these ethical stocks, both among retail as well as institutional investors, means that investors are ready to pay a large amount to buy GBs . Literature has seen a surge in academic works targeting several areas of ethical asset performance, such as the ESG [ , , ], MSCI ESG Leaders (MSCIESGL) GB , clean energy , and the Dow Jones Sustainability Index . Section title: Ethical and safe-haven assets Educational score: 2.473402738571167 Domain: other Document type: Study Language: en Most studies that cover ethical stocks emphasize ESG and the COVID-19 pandemic period, among other risk factors. Rubbaniy et al. find that due to strong positive co-movement between the ESG and COVID-19 fear indices, ethical stocks carry strong safe haven and hedging properties over a medium-term (32–64 days frequency). However, the same attributes do not hold against market volatility (taking VIX as a proxy), particularly in the short-term frequency (0–8 days). Using data from the Arab region for a duration that covers COVID-19, Mousa find that amid the post-pandemic phase, the volatility of ESG stocks was lesser than a composite market index for relatively medium to long terms as the shocks of the pandemic affected the ESG stocks only for a shorter period. Section title: Ethical and safe-haven assets Educational score: 1.2471798658370972 Domain: other Document type: Study Language: en Piserà, Chiappini scrutinized the safe haven and hedging status of the ESG assets from the Chinese market during COVID-19. While they reported strong risk hedging properties of the ESG stocks, they did not have a safe-haven attribute. The study also reported ESG stocks having higher hedging benefits over cryptocurrency. While analyzing the safe haven between ESG stocks and precious metals, Lei, Xue found palladium and gold to be short-period safe havens against ESG markets in North America, Europe, and the developed Asia-Pacific. During the COVID-19 outbreak, the results were robust. Section title: Ethical and safe-haven assets Educational score: 0.6924872994422913 Domain: other Document type: Study Language: en Islamic stocks are also considered ethical because of their strict ethical screening criteria. The Dow Jones Islamic Market World (DJIM) is being used in several studies as the proxy for Islamic ethical assets to investigate the impact of diverse types of shocks, including the GPR, EPU, and OVX . However, the results are mixed. Arif et al. examined the safe haven and diversification benefits of Islamic equities during the pandemic and global financial meltdown. The study found that Islamic equities in the G7 markets lacked safe haven features generally but had strong, safe haven properties during the COVID-19 epidemic. Delle Fogile, Panetta conducted a systematic literature review of the safe properties of Islamic and conventional stocks. They, however, did not report any significant difference between the two competing sectors on the safe haven properties. Section title: Ethical and safe-haven assets Educational score: 0.9980772137641907 Domain: other Document type: Study Language: en Hasan et al. explored the safe haven potential of precious metals, cryptocurrencies, and Islamic equities amid the pandemic and worldwide economic downturn in 2008. They revealed that Islamic stocks were the safe havens during the pandemic as well as the global financial crisis. However, gold and bitcoin were stronger safe haven assets during severe market recessions. Islamic stocks were found to be safe haven assets investments during the economic downturn exhibited by Ref. . Hassan et al. however, found that Gulf Cooperation Country Islamic stock indices failed to safeguard investors throughout the pandemic and the 2008 worldwide financial crisis; sovereign bonds exhibited the most diversification benefit. Section title: Ethical assets and uncertainty factors Educational score: 1.6815217733383179 Domain: other Document type: Study Language: en Recent research has delved into the impact of geopolitical threats on the green economy, examining factors such as institutions, internal conflicts, religion, economic and social issues, and military power . Mauerhofer proposes that sustainable investment is influenced by the effective implementation of sustainability regulations, closely tied to upholding law and order. Additionally, Caldara, Iacoviell have found that geopolitical risks significantly shape investment decisions. Furthermore, Tian et al. have explored the differential effects of geopolitical risks on the green bond markets of China, Europe, and the United States over both short and long terms. Positive and negative shocks to GPR have an adverse short-term impact on GB returns. In the long term, GB returns are positively impacted by negative shocks in GPR and negatively affected by positive shocks in GPR . Ha presents evidence of connectivity between geopolitical risk, renewable energy volatility, and the green bond market during the health pandemic and the period of the Russia invasion of Ukraine. The interplay between economic policy uncertainty (EPU), geopolitical risk (GPR), and the transition to clean energy is a multifaceted subject with significant implications for global financial markets and sustainable development. Recent studies, such as those by Liu et al. have delved into these dynamics, exploring how shifts in energy policy can align with Sustainable Development Goals (SDGs) and mitigate climate change. Consequently, the market for green energy has experienced a notable growth in demand, which may lead to increased stock prices for green energy entities. As Zhao et al. note, the price of renewable energy also responds to the consequences of uncertainty during periods of crisis, such as the COVID-19 epidemic and the Ukrainian war crisis. Section title: Ethical assets and uncertainty factors Educational score: 0.9939416646957397 Domain: other Document type: Other Language: en Other research has also explored the impacts of economic policy uncertainty (EPU) and geopolitical risk (GPR) indexes on global financial markets. Furthermore, studies have recommended transitioning from fossil energy to clean energy to address climate change issues and meet Sustainable Development Goals (SDGs) . As a result, there has been a notable surge in demand for the green energy market, potentially leading to increased stock prices for green energy companies. Additionally, the prices of renewable energy also respond to uncertainty during crisis periods, such as the COVID-19 pandemic and the Ukrainian war crisis . Moreover, Ha demonstrates the link between geopolitical risk, renewable energy volatility, and the green bond market during the health pandemic and the Russia invasion of Ukraine . Section title: Ethical assets and uncertainty factors Educational score: 0.8068593144416809 Domain: other Document type: Other Language: en Previously, researchers have looked into how well financial assets like cryptocurrency, commodities, and international stocks can protect against inflation, economic policy uncertainty (EPU), global economic policy uncertainty, and the VIX (volatility index). However, there has been little research on the hedging and safe haven properties of environmentally friendly (green) assets against different uncertainties. Examining the connection between green securities and macroeconomic variables could open up a new area of research . Section title: Ethical assets and uncertainty factors Educational score: 1.7917468547821045 Domain: other Document type: Study Language: en In summary, past studies reported safe haven features in diverse asset classes, but rarely on green assets and more often on the comparison of the two major shocks: the global financial crisis in 2008 and the COVID-19 pandemic in early 2020. Literature on safe properties and various global uncertainties is limited at best. Moreover, the analysis techniques used in various extant studies are limited in understanding the frequency, complexity, and dependence of uncertainty and asset prices. This study fills these gaps by inspecting the safe haven possessions of seven assets – six ethical asset indices and one conventional stock index – amid geopolitical crises, economic policy uncertainty, and volatility in the stock market. Quantifying the dependency structure between the two time-series variables is critical for analyzing cross-correlation under various market conditions and investment horizons. So, we used two sophisticated methodologies: Quantile Coherence and Wavelet coherence, by taking into consideration multiple market circumstances (bearish, normal, and bullish) at various frequency scales (short-, medium-, and long-term) and the lead-lag connection. Section title: Data and summary statistics Educational score: 1.3520392179489136 Domain: other Document type: Study Language: en This study examines the ethical (SPESG, MSCIESGL, SPGRNB, SPCLN, DJSI, and DJIM) and non-ethical conventional asset performance against three types of uncertainties (GPR, EPU, and VIX). We extract the daily closing price data from October 3, 2011 to September 30, 2021. Refer to Table 1 for details of the data. Table 1 Definition and data sources of selected variables. Table 1 Dimensions Variables Notations Data Sources Uncertainty indices Geopolitical risk GPR www.matteoiacoviello.com Economic policy uncertainty EPU www.policyuncertainty.com The CBOE Volatility Index VIX www.investing.com Asset classes S&P Global 1200 ESG SPESG www.spglobal.com S&P Green Bond SPGRNB S&P Global Clean Energy SPCE Dow Jones Sustainability World DJSI Dow Jones Islamic Market World DJIM S&P Global 1200 SPG1200 MSCI World ESG Leaders MSCIESGL www.msci.com Section title: Data and summary statistics Educational score: 3.117993116378784 Domain: other Document type: Study Language: en Table 2 displays essential descriptive data for the daily returns series of assets studied in this study. The results suggest that mean returns are lower and almost identical in most asset classes. The highest and lowest volatilities are observed in the case of clean energy (SPCE) and green bond (SPGRNB), respectively. However, regarding uncertainty, GPR exhibits greater volatility, followed by EPU shocks. Table 2 Descriptive analysis and unit root tests. Table 2 Variables Mean SD Skew Kurt Jarque-Bera ADF PP SPESG 0.03 0.69 −0.78 30.29 113628.9∗∗∗ −38.25∗∗∗ −55.55∗∗∗ MASCIESGL 0.03 0.68 −0.75 31.98 128037.4∗∗∗ −38.12∗∗∗ −55.79∗∗∗ SPGRNB 0.01 0.28 −0.15 15.76 24770.11∗∗∗ −39.10∗∗∗ −58.23∗∗∗ SPCE 0.02 1.09 −0.29 17.90 33816.58∗∗∗ −36.75∗∗∗ −60.61∗∗∗ DJSI 0.02 0.73 −0.83 26.44 83953.87∗∗∗ −38.22∗∗∗ −55.64∗∗∗ DJIM 0.03 0.74 −1.06 28.00 95740.04∗∗∗ −40.56∗∗∗ −60.61∗∗∗ SPG1200 0.03 0.69 −0.76 28.99 103098.8∗∗∗ −38.25∗∗∗ −55.35∗∗∗ GPR 0.00 53.13 0.15 4.92 573.00∗∗∗ −55.16∗∗∗ −256.36∗∗∗ EPU 0.00 51.81 −0.01 6.64 2012.11∗∗∗ −37.50∗∗∗ −237.88∗∗∗ VIX −0.02 5.98 0.78 11.39 11074.84∗∗∗ −59.01∗∗∗ −61.06∗∗∗ Notes: The table reports the summery statistics. SD stands for standard deviation, and Skew and Kurt are used to denote skewness and kurtosis. The ADF and PP are the Augmented Dickey-Fuller and Phillips-Perron test statistics for unit roots that take into account constants and trends. The ‘∗∗∗’ signify the significance level at 1 %. Section title: Data and summary statistics Educational score: 4.151432514190674 Domain: biomedical Document type: Study Language: en To validate the use of the quantile-based technique, we use the BDS (Broock, Dechert, and Scheinkman) test to assess the non-linearity of our series. Table 3 shows the BDS test results based on time series residuals using a vector autoregressive (VAR) technique in many dimensions (m = 2, 3, 4, …, 6). The null hypothesis of linearity is rejected for all the cases; thus, the non-linearity is further evidenced when implanting diverse dimensions in the BDS test. Consequently, all the diagnostic tests stress us choosing a non-linear estimate technique, which can capture the heterogeneous association between the time series. Table 3 BDS test results for nonlinearity from the VAR model-based residuals. Table 3 Variables m = 2 m = 3 m = 4 m = 5 m = 6 SPESG 0.03∗∗∗ 0.05∗∗∗ 0.06∗∗∗ 0.06∗∗∗ 0.06∗∗∗ MSCIESGL 0.03∗∗∗ 0.05∗∗∗ 0.06∗∗∗ 0.06∗∗∗ 0.06∗∗∗ SPGRNB 0.02∗∗∗ 0.03∗∗∗ 0.03∗∗∗ 0.02∗∗∗ 0.02∗∗∗ SPCE 0.03∗∗∗ 0.05∗∗∗ 0.05∗∗∗ 0.05∗∗∗ 0.04∗∗∗ DJSI 0.03∗∗∗ 0.04∗∗∗ 0.05∗∗∗ 0.05∗∗∗ 0.05∗∗∗ DJIM 0.01∗∗∗ 0.03∗∗∗ 0.04∗∗∗ 0.04∗∗∗ 0.05∗∗∗ SPG1200 0.03∗∗∗ 0.05∗∗∗ 0.06∗∗∗ 0.06∗∗∗ 0.06∗∗∗ GPR 0.02∗∗∗ 0.04∗∗∗ 0.04∗∗∗ 0.04∗∗∗ 0.04∗∗∗ EPU 0.02∗∗∗ 0.04∗∗∗ 0.04∗∗∗ 0.05∗∗∗ 0.04∗∗∗ VIX 0.03∗∗∗ 0.05∗∗∗ 0.05∗∗∗ 0.05∗∗∗ 0.04∗∗∗ Notes: The table presents the BDS test results, which assesses the null hypothesis of independence and identical distribution (i.i.d.) for the time series against an unspecified alternative hypothesis. ∗∗∗ represent the significance level at 1 %. Section title: Data and summary statistics Educational score: 1.11958909034729 Domain: other Document type: Study Language: en Fig. 1 visualizes the correlation matrix. The correlation matrix demonstrates that the GPR and EPU have a zero or near zero correlation with all the asset classes, highlighting the potential of hedging or safe-haven ability. However, VIX has a high negative connection with all asset classes (except SPGRNB). This finding implies that the asset classes chosen in this study are adversely impacted by market volatility. Fig. 1 Visualization of the correlation matrix. Fig. 1 Section title: Quantile coherency model Educational score: 1.3557400703430176 Domain: other Document type: Other Language: en We utilize the dependence structure between numerous ethical and non-ethical asset classes and several uncertainties, especially their quantile connectedness in the joint tails and frequencies of distribution. To capture this, we utilize a quantile cross-spectral dependence methodology (QS) that was originally developed by Kley, Baruník . In a range of market conditions (bearish, normal, and bullish markets), as well as over multiple investment periods (i.e., short, medium, and long-term), this technique can recognize a factor's connection with another, thus, can help in identifying the assets' hedge and safe-haven traits against diverse uncertainties more appropriately. Section title: Quantile coherency model Educational score: 1.205061912536621 Domain: other Document type: Other Language: en Like previous research, we define a hedge as an asset's returns having positive coherence (no or low coherence) with changes in uncertainty on average, indicating a robust (weak) hedge against uncertainties. A strong (weak) safe haven exists when an asset's returns show positive coherence (no or low coherence) with changes in uncertainty under extreme shocks. Section title: Quantile coherency model Educational score: 4.221918106079102 Domain: biomedical Document type: Study Language: en Following conventions stated in extant literature [ , , ], this study sets two stringent stationary processes of factors ( R t ) t ϵ z , with mechanisms R t = ( R t , x , R t , y ) , where x and y are substitutions for a couple of variables. Hence, in the following way (Equation (1) ), the quantile coherency between these two procedures ( R x , y ) can be outlined as follows: (1) R x , y ( ω ; τ 1 , τ 2 ) ≔ f x , y ( ω ; τ 1 , τ 2 ) ( f x , x ( ω ; τ 1 , τ 1 ) f y , y ( ω ; τ 2 , τ 2 ) ) 1 / 2 , where − π < ω < π implies the quantile cross-spectral density and ( τ 1 , τ 2 ) ∊ . f x , y , f x , x , and f y , y state to the quantile spectral densities of procedures R t , x , and R t , y , which can be achieved using the Fourier transform of a matrix of quantile cross-covariance kernels Γ ( τ 1 , τ 2 ) ≔ ( f ( ω ; τ 1 , τ 2 ) ) x , y , where (Equation (2) ) (2) Υ k x , y ≔ C o v ( I { J t + k , x ≤ q x ( τ 1 ) } , I { J t , y ≤ q y ( τ 2 ) } ) , for x , y ∊ { 1 , … , d } , k ∊ z , τ 1 , τ 2 ∊ , and scenario A is specified by function I{A}. We obtain an urgent indication of the cross-section dependency and serial correlation, respectively, by selecting x ≠ y and diversifying k. The quantile cross-spectral density kernel matrix is produced by this frequency's domain as f ( ω ; τ 1 , τ 2 ) ≔ ( f ( ω ; τ 1 , τ 2 ) ) x , y , where (3) f x , y ( ω ; τ 1 , τ 2 ) ≔ ( 2 π ) − 1 ∑ k = − ∞ ∞ Υ k x , y ( τ 1 , τ 2 ) e − i k ω Section title: Quantile coherency model Educational score: 4.082037925720215 Domain: biomedical Document type: Study Language: en We estimate quantile coherency as follows (Equation (4) ), based on Baruník, Kley utilizing smoothed quantile cross-periodograms: (4) G ˆ n , R x , y ( ω ; τ 1 , τ 2 ) ≔ 2 π n ∑ s = 1 n − 1 W n ( ω − 2 π s n ) I n , R x , y ( 2 π s n , τ 1 , τ 2 ) , Where I n , R x , y and W n denote rank-based copula cross-periodograms matrix and order of weight functions respectively. Then, in the following way (Equation (5) ), the quantile coherency valuation can be expressed: (5) R ˆ n , R x , y ( ω ; τ 1 , τ 2 ) ≔ G ˆ n , R x , y ( ω ; τ 1 , τ 2 ) ( G ˆ n , R x , x ( ω ; τ 1 , τ 1 ) G ˆ n , R y , y ( ω ; τ 2 , τ 2 ) ) 1 / 2 Section title: Quantile coherency model Educational score: 3.6799628734588623 Domain: biomedical Document type: Study Language: en This research examines the coherency matrices in connection with three quantiles labeling to upper (0.95), average (0.5), and lower (0.05) quantiles, with the amalgamation of three quantile levels—right (0.95|0.95), middle (0.5|0.5), and left (0.05|0.05)—tails of the joint distribution. Additionally, we separate the coherency into three time horizons: quarterly high value, half-yearly medium value, and annual low value corresponding to ω ∊ 2 π { 1 / 3 , 1/6, 1/12}. Section title: Quantile coherency model Educational score: 3.7339236736297607 Domain: biomedical Document type: Study Language: en From Equation (3) , we can decompose the cross-spectral density of kernels { f x , y ( ω ; τ 1 , τ 2 ) } into real and imaginary parts . The actual portion denotes the co-spectrum of the processes ( I { R t , x ≤ q x ( τ 1 ) } ) t ϵ z and ( I { R t , y ≤ q y ( τ 2 ) } ) t ϵ z , 4 while the imaginary portion represents the quadrature spectrum, which removes a number of sources of noise coherence. Nonetheless, we only provide the actual portions of our quantile coherency calculations due to readability and improved display considerations. 5 Section title: The wavelet coherence (WC) Educational score: 3.325977087020874 Domain: other Document type: Study Language: en As a robustness test, we further analyze our data using the wavelet coherence (WC) approach to explore the lead/lag association between asset classes and uncertainties. It decomposes data into time-frequency space, capturing short-term and long-term patterns. This helps understand market behaviors and interactions between asset classes. The lead-lag relationship is crucial for portfolio management and risk assessment. Wavelet coherency and phase relation techniques reveal correlation and directional intensity over time, providing insights into causality and connectedness. This wavelet coherence (WC) approach eventually proves that the findings of previous methodologies are quite robust and reliable. The WC method, developed by Whitcher, Craigmile , helps scrutinize the time-varying and intensity of co-dependence between pairs in time and frequency domains. Additionally, any possible non-stationarity, nonlinearities, structural breaks, or seasonal patterns in a pair's connection may be controlled with this method . We make use of the cross-wavelet transform (WT) in conjunction with the WC [ , , ]. Among the couple of series x ( t ) and y ( t ) , here is an illustration of the cross-wavelet using continuous wavelet transformations: (6) W x , y ( u , s ) = W x ( u , s ) W y ∗ ( u , s ) , where Equation (6) is the cross-wavelet transformation, and s and u are the scale and position index, respectively. The wavelet transforms of x ( t ) and ( t ) are signified by W x ( u , s ) and W y ( u , s ) , respectively, where ″ ∗ ″ denotes the complex conjugate. According to Torrence and Webster , the co-movement between the two series, x(t) and y(t) , across time and frequency may be evaluated by the WC and is expressed as follows (Equation (7) ): (7) R 2 ( u , s ) = | S ( s − 1 W x y ( u , s ) ) | 2 S ( s − 1 | W x ( u , s ) | 2 S | W y ( u , s ) | 2 ) , where, S states the smoothing operator between time and frequency, recognized by S ( W ) = s s c a l e ( s t i m e ( W n ( s ) ) ) . The coefficient of R 2 ( u , s ) justifies the conditions 0 ≤ R 2 ( u , s ) ≤ 1 in the time-frequency space. R 2 ( u , s ) values closer to zero indicate a poor correlation between the two-time series, which are shown as blue, while values closer to one indicate a high connection, which are shown as warmer (red) colors. There is no link between the series in the cold (blue) zones. Since the WC's theoretical distribution is unknown in this instance, the statistical significance of the coherence is investigated at the 5 % significance level using Monte Carlo simulations . Nevertheless, it is impossible to discern between the lead-lag connection and positive or negative coherency due to the squared value of WC. Torrence and Compo, present a wavelet phase-difference analysis to capture these insufficiencies . (8) Ø x y ( u , s ) = tan − 1 ( J ( S ( s − 1 W x y ( u , s ) ) ) R ( S ( s − 1 W x y ( u , s ) ) ) ) , where (Equation (8) ), the WC phase differences are stated by Ø x y ( u , s ) . The unreal and real parts of the smoothed power spectrum are denoted by J and R , respectively, and are shown with arrows inside the regions classified as having high coherence. The two directions shown by the black arrows are the lead/lag phase relationship and the negative or positive correlation between the couples. The WC estimations across asset classes and uncertainty indices are shown in Fig. 4 , Fig. 6 . The vertical axis' monthly frequencies, such as 4, 8, and 16, represent the short-, medium-, and long-term investment horizons, respectively. 6 Section title: Extreme shocks from uncertainty factors Educational score: 3.0895943641662598 Domain: other Document type: Study Language: en This section looks at how our sample assets have performed against the ten largest shocks that stemmed from three uncertainty factors during the sample period. Table 4 illustrate the returns of SPG1200, DJIM, SPESG, DJSI, SPGRNB, SPCLEN and MSCIESGL in the ten largest daily shocks of uncertainty indicators. We notice that the COVID-19 pandemic was responsible for most of the largest shocks to uncertainty indices, as these shocks happened in 2020 when COVID-19 struck the world unprecedentedly. However, Panel A of Table 4 reports the returns of SPG1200, DJIM, SPESG, DJSI, SPGRNB, SPCLEN and MSCIESGL on the ten biggest shocks derived from the GPR index. The results show that SPG1200, SPESG, DJSI and MSCIESGL returns are positive for six of the ten days; DJIM shows positive returns throughout the whole 10 days, and both SPGRNB and SPCLEN exhibit positive returns for four out of ten days. Table 4 Ten major shocks from five uncertainty factors. Table 4 Panel A: Ten biggest shocks from GPR Date GPR SPG1200 DJIM SPESG DJSI SPGRNB SPCLEN MSCIESGL 07-01-2020 420.29 −0.090 0.013 −0.123 −0.195 −0.225 −0.144 −0.116 09-01-2020 402.58 0.646 0.863 0.579 0.411 −0.155 0.553 0.585 17-11-2015 361.02 −0.050 0.001 −0.061 −0.037 −0.126 −0.220 −0.055 18-11-2015 318.07 −0.050 0.001 −0.061 −0.037 −0.126 −0.221 −0.055 16-11-2015 297.27 0.390 0.258 0.480 0.409 −0.047 −0.928 0.439 12-04-2018 292.84 0.447 0.395 0.396 0.355 −0.365 −0.008 0.407 09-05-2018 289.47 0.636 0.639 0.663 0.447 0.022 −0.528 0.555 05-06-2017 274.77 −0.065 0.027 −0.062 −0.066 −0.035 −0.094 −0.063 06-08-2019 272.20 0.513 0.745 0.518 0.189 0.091 0.646 0.547 19-09-2016 266.86 0.148 0.289 0.141 0.279 0.038 0.482 0.150 Panel B: Ten biggest shocks from EPU 17-05-2020 861.10 1.006 0.004 0.911 0.753 0.053 1.538 0.945 26-04-2020 855.17 0.553 0.008 0.565 0.482 0.036 0.737 0.599 05-05-2020 807.66 0.959 1.244 1.012 1.208 −0.215 1.142 1.043 29-03-2020 743.13 0.702 0.001 0.774 0.863 −0.022 −0.098 0.959 05-04-2020 739.55 1.861 0.001 1.859 1.603 −0.020 1.864 1.934 02-04-2020 738.02 1.290 1.503 1.380 0.896 0.454 0.907 1.333 26-12-2020 699.78 0.076 0.267 0.071 0.033 0.097 −0.265 0.045 26-03-2020 670.30 4.612 4.683 4.725 4.768 2.013 3.274 4.934 22-03-2020 651.07 −1.020 −0.004 −1.018 −1.122 0.035 −2.038 −1.091 27-04-2020 642.66 0.550 1.427 0.562 0.480 0.036 0.732 0.595 Panel C: Ten biggest shocks from VIX 16-03-2020 82.69 −3.345 −9.632 −3.333 −2.986 −0.180 −3.575 −3.426 18-03-2020 76.45 −5.212 −4.415 −5.061 −4.482 −2.410 −10.558 −5.227 17-03-2020 75.91 3.993 3.871 3.992 3.666 −1.587 6.101 4.029 12-03-2020 75.47 −9.976 −9.303 −10.220 −10.61 −2.367 −12.497 −10.250 15-03-2020 74.40 −3.237 −0.003 −3.225 −2.90 −0.180 −3.452 −3.312 19-03-2020 72.00 −0.267 0.493 0.554 0.775 −1.298 1.371 0.751 14-03-2020 66.12 −3.135 −0.003 −3.125 −2.818 −0.180 −3.337 −3.206 20-03-2020 66.04 −2.327 −2.229 −2.365 −1.335 −0.375 1.372 −2.717 27-03-2020 65.54 −2.487 −2.396 −2.509 −2.346 0.763 −5.140 −2.487 21-03-2020 64.56 −1.010 −0.004 −1.008 −1.109 0.035 −1.998 −1.080 Note: The table shows the returns of all assets against the ten biggest uncertainty indices shocks. Section title: Extreme shocks from uncertainty factors Educational score: 1.0672013759613037 Domain: other Document type: Study Language: en Additionally, Panel B reveals the returns of all seven assets on ten extreme shocks in EPU and demonstrates that both SPGRNB and SPCLEN have positive returns on seven out of ten days; Moreover, positive returns for other all remaining assets are documented throughout the ten largest daily shocks. Furthermore, Table 4 Panel C demonstrates that out of the ten biggest shocks, all assets (except DJIM) have eight positive returns in the VIX index. Conversely, SPG1200 return is negative in the biggest shock days in the oil markets, indicating that these assets are likely to be negatively influenced by oil market volatility. According to the analysis above, SPG1200 return seems to be more volatile in the extreme shocks of the sample uncertainty indicators compared to all other assets. Section title: Quantile coherency (QC) estimations Educational score: 1.4150471687316895 Domain: other Document type: Other Language: en Based on Taylor , the returns of the chosen set can be distinguished by positively significant autocorrelations as a constant evolution of return volatility throughout time. To reduce the largest source of autocorrelations, we employ the GARCH (1, 1) model 7 proposed by Barunk, Kley , which can normalize the return series by volatility. Section title: Quantile coherency (QC) estimations Educational score: 2.7354447841644287 Domain: other Document type: Study Language: en We present the outcomes of the quantile coherence estimations in Fig. 2 , Fig. 3 , Fig. 4 . The figures show the higher (0.95|0.95), middle (0.05|0.05), and lower (0.05|0.05) quantiles. On the horizontal axis, the co-dependence of two series is displayed together with the daily cycle over the interval information. Fig. 2 Quantile coherence plots between GPR and seven assets. Notes: The figure depicts the quantile coherence of GPR and seven assets. Each panel describes the relationship between GPR and seven selected assets, e.g., SPESG (i), MSCIESGL (ii), SPGRNB (iii), SPCE (iv), DJSI (v), DJIM (vi), and SPG1200 (vii). The real component of quantile coherency is presented for 0.05, 0.5, and 0.95 quantiles at a 5 % significance level, as per Baruník and Kley . The horizontal axis shows the monthly cycle (0–0.5), denoted by ω/2π. The vertical axis reflects the measure of codependence between a pair of variables. W, M, and Y represent weekly, monthly, and annual time periods, respectively. Fig. 2 Fig. 3 Quantile coherence plots between EPU and seven assets. Note: Each panel describes the relationship between EPU and seven selected assets, e.g., SPESG (i), MSCIESGL (ii), SPGRNB (iii), SPCE (iv), DJSI (v), DJIM (vi), and SPG1200 (vii). The real component of quantile coherency is presented for 0.05, 0.5, and 0.95 quantiles at a 5 % significance level, as per Baruník and Kley . The horizontal axis shows the monthly cycle (0–0.5), denoted by ω/2π. The vertical axis reflects the measure of codependence between a pair of variables. W, M, and Y represent weekly, monthly, and annual time periods, respectively. Fig. 3 Fig. 4 Quantile coherence plots between VIX and seven assets. Note: Each panel describes the relationship between VIX and seven selected assets, e.g., SPESG (i), MSCIESGL (ii), SPGRNB (iii), SPCE (iv), DJSI (v), DJIM (vi), and SPG1200 (vii). The real component of quantile coherency is presented for 0.05, 0.5, and 0.95 quantiles at a 5 % significance level, as per Baruník and Kley . The horizontal axis shows the monthly cycle (0–0.5), denoted by ω/2π. The vertical axis reflects the measure of codependence between a pair of variables. W, M, and Y represent weekly, monthly, and annual time periods, respectively. Fig. 4 Section title: Quantile coherency (QC) estimations Educational score: 2.5424158573150635 Domain: other Document type: Study Language: en Fig. 2 depicts the quantile coherency estimations of GPR paired with every asset considered in this study. Fig. 2 (i) displays an average negative coherence for the GPR-SPESG pair across the lower return quantile (0.05|0.05). Conversely, a significant positive co-movement between GPR and SPESG is noticed in terms of short-run (weekly) frequency in normal return quantile (0.5|0.5), while both medium- and long-term horizon reveals a negative coherence. However, a positive upward movement is observed for the long-term horizon, though the correlation experiences a downward trend after crossing the yearly horizon in the upper return quantile (0.95|0.95). Section title: Quantile coherency (QC) estimations Educational score: 1.4639886617660522 Domain: other Document type: Study Language: en Similar patterns of coherence are clear in the case of the GPR-MSCIESGL pair ( Fig. 2 (ii)), where a significant positive correlation exists in the average quantile for short-term and upper quantile for long-term frequencies. Consequently, against GPR, SPESG has strong hedging properties only in the normal market condition in short-term frequency, while MSCIESGL contains strong, safe haven opportunities in long-term frequency. Ahad et al. also suggest that a safe haven portfolio with a one-month investment horizon can yield positive returns during wartime, suggesting investors should consider ESG indices as safe assets during crises. Section title: Quantile coherency (QC) estimations Educational score: 1.8641952276229858 Domain: other Document type: Study Language: en The quantile correlation between GPR and SPGRNB, shown in Fig. 2 (iii), demonstrates an average negative association in most quantile and frequency scales. However, in normal market conditions, both long- and medium-term returns show a significant positive co-movement. In bearish market conditions, only long-term coherence is significantly positive, while a non-continuous peak is observed in the weekly horizon in the upper quantile. On the other hand, in Fig. 2 (iv), the GPR-SPCE pair exhibits negative dependence in both yearly and monthly frequencies, whereas the weekly frequency unveils an average positive association in the lower quantile. Section title: Quantile coherency (QC) estimations Educational score: 1.3216485977172852 Domain: other Document type: Study Language: en Furthermore, the normal return quantile reveals that SPCE has a significant favorable connection with GPR in the yearly horizon and an average negative association in the monthly horizon. An average positive or zero correlation in the weekly investment horizon is noticed. However, in the upper return quantile, a significant positive coherence exists in the long-term until the mid of the medium-term horizon, while an average negative association is concluded in short-term frequency. These findings imply that SPGRB offers hedging opportunities in the long-term, whereas the SPCE provides the same both medium- and long-term frequencies for normal market conditions. Both SPGRB and SPCE provide a strong safe haven in long-term frequency only in bullish market conditions. Section title: Quantile coherency (QC) estimations Educational score: 1.2369858026504517 Domain: other Document type: Study Language: en Fig. 2 (v) illustrates an average positive dependence structure between GPR and DJSI in normal return quantile, except for the long-term. Conversely, a strong positive upward coherence in the long-term quantile is noticed, though it turns to a negative region after crossing the middle of the monthly horizon. For the rest of the time and frequency scales, even in the case of extremely lower quantiles, the coherence between GPR and DJSI is negative on average. These results entail the weak hedging capabilities of DJSI against GPR for medium- and short-term returns in normal market conditions. DJSI can provide strong, safe haven benefits during the buying pressure market condition. Sustainable development objectives, according to Oliveira et al. , can assist asset managers, investors, and other stakeholders in reducing the detrimental consequences of local and global measures of uncertainty. Section title: Quantile coherency (QC) estimations Educational score: 1.4785752296447754 Domain: other Document type: Study Language: en As depicted in Fig. 2 (vi), it can be observed that the GPR-DJIM pair exhibits a steadily adverse link with the extremely lower return quantile across various time-frequency intervals. On the other hand, it can be observed that the GPR-DJIM pair displays a significant positive coherence over the time span in the quantile associated with normal returns. This suggests that the pair has considerable potential for hedging in typical market conditions. Notwithstanding the robust positive long-term coherence, bull market conditions exhibit a negative association on average in both the short- and medium-term periods. The findings suggest that DJIM has the potential to serve as a hedging instrument, particularly in typical market circumstances across various frequencies. Additionally, DJIM can function as a robust hedge and a safe haven against GPR shocks in the long-term frequency when the market is bullish. This discovery is in line with the research conducted by Hasan et al. , which posits that the conservative nature of Islamic markets, characterised by limitations on interest, gambling, and speculative practices, renders them less vulnerable to financial upheavals. Section title: Quantile coherency (QC) estimations Educational score: 1.9102188348770142 Domain: other Document type: Study Language: en Fig. 2 (vii) demonstrates a positive coherence between GPR and SP1200 in the weekly timeframe in the lower return quantile. Additionally, a robust positive correlation is evident in the short-term period in the normal quantile. Furthermore, it has been observed that a favorable negative correlation exists in the annual timeframe for the normal return quantile. Conversely, a favorable positive correlation is evident for the higher quantile in the GPR-SP1200 pair. However, in all other instances, there exists a feeble unfavorable correlation between them. Section title: Quantile coherency (QC) estimations Educational score: 1.6340280771255493 Domain: other Document type: Study Language: en Fig. 3 displays the quantile coherency of EPU paired with all the assets. Fig. 3 (i) exhibits an average negative connection between EPU and SPESG in the lower quantile at the weekly frequency and a strong negative association in the yearly frequency, whereas a strong positive association is found in the monthly frequency. Conversely, in the case of normal and upper return quantiles, we notice a negative association in the long- and medium-term frequencies, while a positive coherency is observed in the short-term frequency. Furthermore, the MSCIESGL-SPESG pair in Fig. 3 (ii) exhibits similar findings. These findings imply that both MSCIESGL and SPESG may have hedging potentials against EPU in the medium-term frequency at bearish market conditions. The hedging opportunity is weak in normal and bullish market conditions for short-term frequency. Section title: Quantile coherency (QC) estimations Educational score: 2.4695653915405273 Domain: other Document type: Study Language: en Turning to the EPU-SPGRNB pair, in lower quantiles, Fig. 3 (iii) reports an average positive association between EPU and SPGRNB at medium- and short-term frequencies. Conversely, in the extremely higher return quantile, the pair shows an average negative association except for monthly frequency. Except for the short-term frequency in normal return quantile, there is a favorable co-movement in long- and medium-term frequency. Hence, based on these results, SPGRNB can be used as a weak hedging tool. These results are similar to Pham, Nguyen's that GBs and uncertainty are weakly related during periods of relatively lower uncertainty, allowing GBs to be utilized as a hedge against EPU. Section title: Quantile coherency (QC) estimations Educational score: 1.9124255180358887 Domain: other Document type: Study Language: en Fig. 3 (iv) demonstrates a favorable association between EPU and SPCE for the monthly frequency at lower quantiles, while it turns negative in the weekly horizon. Conversely, the EPU-SPCE pair in normal return quantile reveals an average positive coherence in both short and medium-term frequencies and a strong positive co-movement in higher return quantiles, except for medium-term. Thus, our findings suggest that SPCE can hedge the EPU strongly in medium-term frequency at bearish market conditions while serving as weak hedging for the normal return quantile. However, except for medium-term frequency, SPCE contains both hedge and safe-haven potentials at bullish market conditions against EPU. Section title: Quantile coherency (QC) estimations Educational score: 1.4847575426101685 Domain: other Document type: Study Language: en Regarding Fig. 3 (v), it can be observed that only the medium-term horizon within the lower quantiles manifests a robust positive correlation between DJSI and EPU. A typical positive relationship is observed in the context of short-term frequency during a market condition characterized by a bullish trend. Fig. 3 (vi) demonstrates a consistent positive coherence in the medium-term frequency at lower quantiles and an average association in the short-term horizon for DJIM. An observation can be made regarding the positive coherence of DJIM, which is found to be consistent across various investment horizons. Fig. 3 (vii) demonstrates that the EPU-SPG1200 pair displays exclusively robust positive interdependence during medium-term frequency in a bearish market environment. Section title: Quantile coherency (QC) estimations Educational score: 1.073296308517456 Domain: other Document type: Other Language: en In contrast, it is observed that normal and bullish market conditions exhibit a tendency towards positive returns on average in the short term. The aforementioned findings demonstrate that SPCE, DJIM, and SPG1200 assets can serve as effective hedging instruments for medium-term investors seeking to mitigate the adverse effects of EPU in bearish market conditions. Conversely, in bullish market conditions, investors may solely benefit from hedging and safe-haven strategies to mitigate exposure to economic policy uncertainty (EPU). Section title: Quantile coherency (QC) estimations Educational score: 1.8126060962677002 Domain: other Document type: Study Language: en The quantile dependence structure between seven selected assets paired with VIX is depicted in Fig. 4 (i)–(ii),(iii),(iv),(v),(vi)&(vii). Most pairs demonstrate a highly unfavorable co-movement, except for certain frequencies and quantiles. Initially, the pairs demonstrate that at lower return quantiles, the long-term horizon displays a robust positive correlation with VIX. However, a maximum positive coherence is observed at the intersection of the weekly and monthly horizons for equally extreme market conditions. In contrast, each asset set exhibits a highly negative correlation with the VIX under typical market circumstances. However, SPGRNB (as depicted in Fig. 4 (iii)) displays a moderately positive correlation on average across short-term market conditions. The VIX-SPGRNB pair exhibits a robust positive correlation in both monthly and yearly timeframes, even during periods of heightened market volatility. Thus, drawing from these results, it can be concluded that only SPGRNB exhibits robust safe-haven characteristics at both medium- and long-term frequencies when compared to VIX. The findings indicate that all seven assets exhibit robust hedging characteristics in the long term during bearish market scenarios. However, it is noteworthy that only SPGRNB demonstrates a feeble hedging capability in the short term compared to VIX across all market conditions. Section title: Wavelet coherence analysis Educational score: 3.7923176288604736 Domain: biomedical Document type: Study Language: en To further provide comprehension into the co-movement of variables under study in the time-frequency domain, the WC methodology is employed. Fig. 5 , Fig. 6 , Fig. 7 depict the relationships between three global risk and uncertainty factors and seven distinct asset classes in terms of their WC plots. WC metric evaluates the time-frequency associations as well as the causal relationships between the respective variable pairs. The time dimension is represented by the horizontal axis, while the frequency dimension is depicted by the vertical axis. The degree of association is shown by the color on the right side of the bar chart. From blue (near low coherence) to red (high coherence), the coherence color code is used. The black U-shaped curve represents the cone of influence (COL). The areas of significant coherence within COL are delineated by dark contours. The scale (number of days) shows the frequency domain, highlighting that the short, medium, and long-term frequency domains imply the short, medium, and long-run investment horizons, respectively. Fig. 5 Wavelet coherence between GPR and seven assets. Note: The figures exhibit the wavelet coherence (WC) pairwise plots between GPR and seven assets. The horizontal axis displays time frames, whereas the vertical axis represents frequency in days. The arrows show the phases that correlate to the variables. The two series are in phase (anti-phase), as shown by the arrows on the right (left) side. The first (second) variable is shown as leading by the arrows, which are pointing right-side down (up) and left-side up (down). Fig. 5 Fig. 6 Wavelet coherence plots between EPU and seven assets. Note: The figures exhibit the wavelet coherence (WC) pairwise plots between EPU and seven assets. The horizontal axis displays time frames, whereas the vertical axis represents frequency in days. The arrows show the phases that correlate to the variables. The two series are in phase (anti-phase), as shown by the arrows on the right (left) side. The first (second) variable is shown as leading by the arrows, which are pointing right-side down (up) and left-side up (down). Fig. 6 Fig. 7 Wavelet coherence plots between VIX and seven assets. Note: The figures exhibit the wavelet coherence (WC) pairwise plots between VIX and seven assets. The horizontal axis displays time frames, whereas the vertical axis represents frequency in days. The arrows show the phases that correlate to the variables. The two series are in phase (anti-phase), as shown by the arrows on the right (left) side. The first (second) variable is shown as leading by the arrows, which are pointing right-side down (up) and left-side up (down). Fig. 7 Section title: Wavelet coherence analysis Educational score: 1.3029474020004272 Domain: other Document type: Other Language: en The graphical representation depicted in Fig. 5 illustrates the WC plot of a set of seven assets in conjunction with the GPR. It is observed that within the COL, the time-frequency planes are predominantly characterized by cool hues for each respective index. This Section title: Wavelet coherence analysis Educational score: 1.0651843547821045 Domain: other Document type: Other Language: en suggests a lack of coherence between all assets and GPR. All indices appear to be devoid of any influence from GPR and offer a secure refuge against GPR shocks, even amidst the COVID-19 pandemic. Section title: Wavelet coherence analysis Educational score: 2.0838639736175537 Domain: other Document type: Study Language: en The pairwise WC plot between the EPU and seven assets is also presented in Fig. 6 . The seven assets are depicted in a cold color, suggesting limited connectivity to the EPU across various timeframes and magnitudes. Despite this, several small but significant islands within the COL exhibit a red coloration accompanied by leftward-pointing arrows, indicating an anti-phase relationship within the medium-to-long-term frequency range of 64–1024 days. This pattern was observed during 2012, 2014–2015, and 2019–2021, except for the SPGRNB-EPU plot. This suggests that while assets generally offer a secure investment option, they may exhibit negative behavior with respect to EPU during times of economic downturn, stock market declines, and the COVID-19 pandemic, except for SPGRNB. The present study's results concur with those of Arif et al. who established that the returns on GBs appear to have become more persistent following the emergence of the COVID-19 pandemic. Section title: Wavelet coherence analysis Educational score: 2.0641627311706543 Domain: other Document type: Study Language: en The outcomes of the analysis of the relationship between the VIX and seven financial assets, namely, SPESG, MSCIESGL, SPGRNB, SPCE, DJIS, DJIM, and SPG1200) are illustrated in Fig. 7 . An anti-cyclic (out-of-phase) association is observed between VIX and many asset classes, except SPGRNB and SPCE, across all periods and time frames. Similarly, the long-term horizon of CDS-stock (CDS-VIX) pairs shows a strong negative (positive) association . The directional movement of all arrows is towards the left, indicating a primarily leading effect by VIX. The findings indicate a substantial adverse connection between SPESG and the VIX, implying that SPESG is not able to effectively mitigate the risks associated with stock market fluctuations. Furthermore, it is observed that there exists a lack of coherence or absence of coherence between SPGRNB and VIX across all time and frequency domains. This leads to the conclusion that SPGRNB is not negatively impacted by VIX shocks. A mixed relationship between the SPCE and VIX is witnessed. In the short, medium, and long-term scales, certain arrows indicate a leftward (anti-phase) upward trend, implying a negative correlation between VIX and SPCE, with VIX leading. Notably, most islands in both the time and frequency domains exhibit a prevalence of cool hues, signifying a lack of coherence between SPCE and VIX. Section title: Summary of the findings Educational score: 3.5331852436065674 Domain: biomedical Document type: Study Language: en The present study employs two distinct methodologies, namely quantile coherence and wavelet coherence, to comprehend the time-frequency, time domain and lead-lag associations between risks and seven asset classes. The quantile coherence findings suggest that the variables exhibit co-integration with time-frequency, indicating the existence of three distinct markets: bearish, normal, and bullish. In contrast, the wavelet coherence analysis reveals the presence of co-movement among the variables across various time domains, including short, medium, and long-run periods, along with quantile coherence. Section title: Summary of the findings Educational score: 1.8959214687347412 Domain: other Document type: Study Language: en Based on the quantile coherence analysis, we examine the relationship between various assets and the GPR and EPU. Our findings indicate that during a bullish market, all assets demonstrate safe haven properties against the GPR and EPU on a yearly and weekly basis, respectively. SPGRNB exhibits minimal correlations in this regard. Notably, the MSCIESGL and SPGRNB exhibit monthly and yearly frequencies, indicating their potential as safe-haven assets during elevated stock market volatility, as measured by the VIX. During a market downturn, the GPR has a negative impact on all assets, apart from SPGRNB. Conversely, EPU has a positive effect on assets at a monthly frequency. Doğan et al. reveals the economic policy uncertainty indicator's impact varies across markets, emphasizing the significance of green bonds as a safe haven during uncertainty. Nonetheless, it is noteworthy that all assets function as hedges and safe-haven assets in relation to VIX on an annual basis while exhibiting a monthly correlation with SPGRNB. In a typical market scenario, except for DJIM exhibiting a positive response, all other assets demonstrate a neutral reaction towards GPR and EPU. However, across all frequencies, all assets exhibit a negative performance on the VIX, except for SPGRNB. Section title: Summary of the findings Educational score: 1.5023711919784546 Domain: other Document type: Study Language: en In addition to our quantile coherence, we have employed wavelet coherence analysis. It can be inferred that there is a minimal or negligible level of co-movement between GPR and the various assets studied. This suggests that these asset classes exhibit characteristics of safe-haven properties in relation to GPR. The EPU index has produced mixed outcomes, including negative co-movement and absence of co-movement. SPGRNB and SPCE are consistently regarded as safe havens, in contrast to other assets which exhibit negative associations during times of crisis such as economic growth recession , stock market selloffs , and the COVID-19 outbreak. Furthermore, regarding the VIX, it can be observed that all assets, except SPGRNB, experience a negative impact. Therefore, it is likely that SPGRNB and SPCE serve as secure assets that mitigate the potential risks and uncertainties associated with GPR, EPU, and VIX. Section title: Conclusion and implications Educational score: 1.0254708528518677 Domain: other Document type: Study Language: en In the next decade, corporations are expected to prioritize addressing climate change as a serious issue. Therefore, ethical assets have emerged as a viable investment option to protect investors from market downturns. This paper adds contributions to the existing knowledge on ethical finance, focusing on environmental and religious ethical aspects. Specifically, the study examines the quantile dependence of six ethical assets (SPESG, MSCIESGL, SPGRNB, SPCE, DJSI, and DJIM), as well as conventional assets , in relation to various risks and uncertainty indices (GPR, EPU, and VIX). The research utilizes two novel techniques, quantile coherence and wavelet coherence, during the time span of October 3, 2011, to September 30, 2021. Section title: Conclusion and implications Educational score: 1.2928019762039185 Domain: other Document type: Study Language: en The outcomes suggest that GPR shocks have a favorable or neutral impact on all assets across different markets and time periods, except for bearish and bullish markets with monthly frequency. This implies that ethical assets can serve as a protective measure against GPR shocks. The study also investigates the potential hedging capabilities of environmental ethical (sustainability), religious ethical (DJIM), and non-ethical assets against EPU. Most of the analyzed assets show favorable outcomes in terms of coherence with EPU at lower quantile levels in monthly frequencies and middle to upper quantile levels in weekly frequencies. This indicates that these assets have the potential to mitigate the impact of EPU shocks in various market states. However, except for SPGRNB and SPCE, the assets have been adversely affected by EPU shocks resulting from the COVID-19 outbreak and the economic crisis across diverse markets, frequencies, and time periods. Section title: Conclusion and implications Educational score: 1.1757633686065674 Domain: other Document type: Other Language: en On the contrary, the returns of various asset indices exhibit significant susceptibility to fluctuations in VIX, indicating a lack of hedging capabilities against unexpected VIX disturbances. The positive trajectory that VIX exhibits under adverse market conditions can be advantageous to long-term investors. Conversely, the assets MSCIESGL and GRNB demonstrate a positive response to high stock market volatility, particularly during bullish market conditions, as evidenced by their performance in both yearly and monthly frequencies. This suggests that these assets possess a safe-haven characteristic that enables them to withstand periods of heightened stock market volatility. It is important to note that most assets have the ability to absorb risks associated with GPR, EPU, and VIX through diversification channels. Among the green assets, SPGRB and SPCE exhibit superior performance across all dimensions and offer opportunities for hedging and safe-haven investments. Section title: Conclusion and implications Educational score: 1.5123883485794067 Domain: other Document type: Study Language: en The results of this study hold noteworthy ramifications for stakeholders such as investors, fund managers, policymakers, and governments in terms of sustainable development, improved investment strategies, and informed policymaking in diverse market conditions, investment timelines, and levels of uncertainty. By evaluating ethical and non-ethical indices in the face of unexpected fluctuations in GPR and EPU shocks, investors and risk managers can enhance their investment strategies to better navigate diverse risk and market conditions. An optimal portfolio can be constructed to diversify the risk of GPR and EPU. Furthermore, in cases where uncertainties arise from the Volatility Index (VIX), particularly in a typical market scenario, it is advisable for investors to refrain from investing in the assets that have been scrutinized in this research, as these assets are adversely impacted by fluctuations in the VIX. Nevertheless, investors and asset managers who prioritize environmental concerns may be leading the way toward a novel investment paradigm, and the financial sector plays a vital role in facilitating the transition toward an economy that aims to mitigate the impact of climate change. Beside this, investors who prioritize ecological considerations may opt to invest in environmentally friendly markets such as SPGRNB and SPCE, as they offer a secure investment option, portfolio diversification, and a commitment to sustainable practices. Section title: Conclusion and implications Educational score: 1.165526270866394 Domain: other Document type: Other Language: en Additionally, it is imperative for policymakers operating within these markets to remain cognizant of the unpredictable and hazardous scenarios that may arise as a result of market instability, remain abreast of evolving GPR and EPU shock circumstances and implement necessary measures to mitigate these risks. Upon assessing these factors, policymakers can effectively determine suitable courses of action to address potential risks and uncertainties. The present investigation adds to the extant body of literature by tackling significant environmental issues and furnishing persuasive proof that ethical markets, via their distinct risk-absorption mechanism, can proficiently absorb investment risk while mitigating and diversifying the risk of ambiguity. Section title: Conclusion and implications Educational score: 1.5458275079727173 Domain: other Document type: Study Language: en While this study provides a solid foundation for future researchers, it is not exempt from limitations akin to other investigations. Our analysis is limited to a single conventional asset, assigned a specific level of risk and uncertainty. The integration of ethical assets with conventional assets, along with the analysis of various risk and uncertainty components, can facilitate a comprehensive understanding of the underlying interconnections among these factors. We have not also covered precious metals and cryptocurrency due to the potential complexity that may arise while finding a common coherence among these different types of markets. Section title: • Credit author statement Educational score: 0.9163039326667786 Domain: other Document type: Other Language: en All authors equally contributed to the paper. Section title: • Availability of data and materials Educational score: 0.8786713480949402 Domain: other Document type: Other Language: en The data sources are given in the data and methodology section of the paper. The datasets are provided on reasonable request. Section title: Funding Educational score: 0.9938948750495911 Domain: other Document type: Other Language: en There are no funding sources. Section title: CRediT authorship contribution statement Educational score: 0.9692812561988831 Domain: other Document type: Other Language: en Md Bokhtiar Hasan: Writing – review & editing, Writing – original draft, Supervision, Software, Methodology, Formal analysis, Conceptualization. M. Kabir Hassan: Writing – review & editing, Supervision, Conceptualization. Mamunur Rashid: Writing – review & editing. Tanzila Akter: Writing – original draft, Software, Methodology, Formal analysis, Data curation, Conceptualization. Humaira Tahsin Rafia: Writing – original draft, Software. Section title: Declaration of competing interest Educational score: 0.9818206429481506 Domain: other Document type: Other Language: en The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. | Other | other | en | 0.999996 |
PMC11699256 | Section title: Introduction Educational score: 3.723229169845581 Domain: other Document type: Review Language: en Sometimes people remember information about the source of a prior event correctly (such as background, location, or other kinds of context) without fully recollecting the details of the event. 1 , 2 , 3 For instance: “this place seems familiar, but I don’t know why or what from” or “I know the general place where I read something (e.g., the bottom left hand part of a page of a book), but I can’t remember what it was (e.g., neither the page nor the specific information)”. 4 , 5 It is not clear how this phenomenon occurs in memory. Cognitive models have typically accounted for episodic memory through two processes (for Review, see 6 ): “familiarity” recognizes an item from the past but with varying levels of memory strength and lacking contextual details, whereas recollection retrieves the item bound within the contextual details it was experienced with in the past, such that researchers typically used context retrieval as a proxy for recollection. Familiar recognition of a context in the absence of recollection is thus a puzzle for memory theories because it is difficult to resolve the paradox with just the two processes of recollection and familiarity, but these memories happen nonetheless. 1 , 3 , 4 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 Section title: Introduction Educational score: 4.219772815704346 Domain: biomedical Document type: Study Language: en A prior study investigated this conundrum using event-related potentials (ERPs) to focus on the unique memory condition in which people reported low confidence recognition of an item but had accurate source memory for the item’s context. 1 It was found that familiar context can be retrieved without relying upon recollection, thereby demonstrating that these constructs are dissociable and not dependent .The ERPs associated with this condition were electrophysiologically distinct from those associated with the memory process of recollection. The condition was therefore named “context familiarity”, based upon the framework of the binding-in-context (BIC) model, 15 , 16 , 17 which proposes that items and contexts are processed differently in the parahippocampal gyrus of the medial temporal lobe, and that the hippocampus binds the item within the context it was experienced in, e.g., recollection. Figure 1 Memory test schematic and combinations of conditions analyzed A (left): For each of 216 items studied and 108 new item lures, participants responded to a memory test that first asked them to rate their recognition confidence on a scale from 1 to 5 for if they thought the word on the screen was an old item from the study phase or if they thought it was a new item. Immediately following the item recognition judgment, participants were asked to indicate their source memory, e.g., if they remembered which study task the item was encountered in during the study phase. If they could not remember, they were instructed to then press the ‘3’ key to indicate that the source was unknown. (B) (right): schematic identifying the response profile for the three main conditions of interest analyzed in the current study. Green: item recognition hits collapsed across confidence levels, and which received responses of having no source memory, were operationalized as “item familiarity” (iFam. 18 , 19 ). Blue: low confidence recognition hits (responses of ‘4’) that received correct source memory judgments were operationalized as ‘context familiarity’ (cFam. 1 ). Red: high confidence recognition hits (responses of ‘5’) that received correct source memory judgments were operationalized as “recollection” (Rec. 1 , 15 , 20 , 21 , 22 ). Right: Representative ERP results of context familiarity and recollection are depicted from the original findings 1 (reproduced with permission of the owner), shown as topographic maps of each condition plotted in comparison to correct rejections during the latency of 600–800 ms in the memory epoch, with color scale depicting difference amplitudes (from −2 to 2 μV) of each condition as compared to correct rejections. Section title: Introduction Educational score: 4.1866960525512695 Domain: biomedical Document type: Study Language: en The ERP effects for this “context familiarity” manifested generally as a widespread fronto-central-parietal negative-going effect. This occurred at approximately 600 milliseconds (ms) after stimulus presentation and extended later in the epoch from 800 to 1200 ms when compared to both correct rejections as well as when compared to incorrect source judgments. 1 This relatively late, broad central negativity (BCN) was dissociated from the late positive component (LPC) effect that is well-associated with recollection and did not show signs of an FN400 effect often related to familiarity. However, that study did not directly address whether the effects of context familiarity were dissociable from those of item familiarity. Therefore, it has remained unknown whether there is one type of overarching familiarity process that includes representations of both item and contexts (e.g., the BIC model) or if there might be two separable forms of familiarity: one for items and one for context. Section title: Introduction Educational score: 4.239462852478027 Domain: biomedical Document type: Review Language: en As a brief primer, in human long-term memory, theoretical models of conscious episodic recognition have been largely governed by the dual cognitive processes of familiarity and recollection. 6 , 15 , 16 , 20 , 21 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 Recollection is operationalized as the declarative retrieval of episodic information (i.e., an event) specifically with both the item and context of the event bound together into a cohesive retrieval of the episode (for review see 16 ). Recollection is usually associated with the confident retrieval of contextual information surrounding the item of the event (for reviews see 6 , 28 , 36 ). The item in the event, however, may be retrieved without recollection, instead relying upon a process of general familiarity of the episodic information, typically conceptualized as declarative, conscious retrieval of an item from a prior episode but without the associated confidence, recollection, or contextual information in which it occurred. Section title: Introduction Educational score: 4.409900665283203 Domain: biomedical Document type: Review Language: en These two memory phenomena are dissociable cognitive processes 21 with differential neural substrates in the medial temporal lobes, 38 , 39 , 40 , 41 are neuropsychologically dissociable among patient impairments, 22 , 42 , 43 and demonstrate spatiotemporally distinct patterns of electrophysiology at the scalp (ERPs) 1 , 44 , 45 , 46 ; for review see. 47 , 48 Familiarity has been associated with positive ERP differences in memory trials during a negative-going ERP peak at the mid-frontal scalp sites that occurs at approximately 400–600 ms post stimulus, often called the mid-frontal old-new effect, or FN400 (for f rontal- N 400 effect). On the other hand, recollection has been associated with positive differences between memory conditions occurring at a peak in the ERP at the parietal region of the scalp from approximately 600 to 900 ms, often referred to as a late parietal component (LPC) or parietal old-new effect 1 , 49 ; for reviews see. 45 , 47 , 48 Section title: Introduction Educational score: 4.09709358215332 Domain: biomedical Document type: Review Language: en Among studies of episodic recollection, “source memory” has been one of the most reliable methods of assessing recollection for episodic events in both behavioral and cognitive neuroscience paradigms. That is, it has traditionally been assumed that if someone remembers the source of information, then they must have retrieved information about the context of that memory and hence “must” be recollecting that episode. As such, source memory has served as one of the most useful proxies for understanding memory and amnesia deficits, 22 despite researchers widely acknowledging that source memory is not process-pure as an exclusive measure of recollection. 3 , 35 , 50 , 51 , 52 , 53 , 54 , 55 , 56 Prior research has also identified the role that other processes can contribute to source memory, 57 including item-familiarity 52 , 58 , 59 , 60 and unitization of two items into a new association. 60 , 61 , 62 , 63 , 64 , 65 Section title: Introduction Educational score: 4.151628017425537 Domain: biomedical Document type: Study Language: en The findings of ERP dissociations for context familiarity and recollection as occurring at different times and different sites on the scalp 1 provided direct physiological evidence in support of the BIC model’s theory and related variants 6 , 15 , 16 , 17 , 27 , 48 ; however, there remained limitations. In particular, while those findings had demonstrated that context familiarity was reliably distinct from recollection, 1 it was unknown if context familiarity is also directly dissociable from item familiarity or whether it is operating merely as a component element of the same memory process of generic familiarity that governs both items and contextual representations. 16 The notion that context can be differentially familiar than item information has been suggested in prior studies, 4 , 5 , 66 but was viewed only as context familiarity being merely a variant of the same underlying process of familiarity, and lacked evidence of an independent process until the aforementioned ERP study. 1 Here, we put forth evidence for a fundamentally different view: that familiarity of context differs qualitatively from item familiarity. Section title: Introduction Educational score: 4.148767471313477 Domain: biomedical Document type: Study Language: en The focus of the present investigation was to assess if the ERP effects for context familiarity can be reliably dissociated from those for item familiarity, and to add novel insights from behavioral measures of response times. When prior investigations observed dissociable ERP activity in time and topography for conditions of recollection (LPC) and familiarity (FN400), it was considered compelling evidence of two independent memory processes, 44 , 46 , 47 that reflect dual-process models of episodic recognition, since a single process would not have (and has not) been able to account for such patterns of neurophysiology without substantial post-hoc modifications. 6 , 48 In turn, if the effects of context familiarity are found to be dissociable in ERPs and/or behavior, it could be taken as evidence that context familiarity is a distinct additional process of episodic memory that extends beyond the traditional dual processes of recollection and item-familiarity. Section title: Introduction Educational score: 4.11956787109375 Domain: biomedical Document type: Study Language: en Toward that end, we re-analyzed a published ERP dataset ( N = 54) 18 , 67 that utilized the same paradigm as prior studies 1 , 22 and tested a combination of item recognition confidence and source memory judgments. We directly assessed behavioral measures of response times and physiological measures of ERPs for the three conditions of “item-only hits with source unknown” (‘item familiarity’ 18 , 19 ), “low-confidence recognition hits that had correct source memory” (‘context familiarity’ 1 ), and “high-confidence hits that had correct source memory” (‘recollection’ 1 ) . To preface our findings, we found that context familiarity, item familiarity, and recollection were each dissociable in neural activity patterns occurring at different times and places on the scalp, as well as in behavioral measures of response times for both item and source memory judgments (Experiment 1), and that the electrophysiological findings replicated across several independent studies (Experiment 2). Section title: Behavioral performance Educational score: 4.1470489501953125 Domain: biomedical Document type: Study Language: en In the current study, when people had low-confidence recognition (item 4 judgments) they went on to provide accurate source discrimination judgments significantly above chance (considered as 0.50, see Method) (M = 0.572, SD = 0.18, SE = 0.03; t(47) = 2.85, one-tailed p = 0.003; Cohen’s d = 0.40, 95% CI [0.521, 0.623]) ( Table 1 ), which was (and replicated) the same level of source memory performance as was previously reported 1 (M = 0.576, SD = 0.15, SE = 0.03, 95% CI [0.517, 0.635]). This null difference was quantified by finding no significant differences between the present study and the preceding one 1 (t(71) = 0.081, p = 0.936, 95% CI [-0.080, 0.087], BF 01 = 3.95). Having established the reproducibility of the prior behavioral performance of memory responses, 1 we next explored the response speeds and electrophysiological correlates of this paradoxical combination of memory response patterns. Table 1 Proportions of overall response patterns for recognition hits and source judgment combinations for old items during the memory test Response Proportions Source Incorrect Unknown Source Correct Total Sure Unsure Unsure Sure Per total Old Items Item 4: Unsure ‘Old’ <0.01 0.05 0.02 0.06 0.02 0.16 Item 5: ‘Sure Old’ 0.12 0.07 0.04 0.11 0.30 0.64 Total 0.14 0.14 0.22 0.18 0.33 Per Confidence Level Item 4: Unsure ‘Old’ 0.05 0.32 0.14 0.38 0.10 1.00 Item 5: ‘Sure Old’ 0.19 0.11 0.07 0.17 0.47 1.00 Per Total Hits Item 4: Unsure ‘Old’ 0.01 0.07 0.03 0.08 0.02 0.20 Item 5: ‘Sure Old’ 0.15 0.09 0.05 0.13 0.37 0.80 Total 0.16 0.15 0.08 0.21 0.39 Each participant ( N = 54) had 216 trials of old items. Left hand column represents item recognition confidence responses, and successive columns denote source memory responses. Top subsection provides the overall proportion of responses of high- and low-confidence recognition hits for each level of source judgment, out of all old trials (214 trials for each of N = 54 participants). Middle subsection indicates the proportion of responses for each source judgment per high- and low-confidence recognition hits; e.g., when subjects did have a recognition hit, it indicated what proportion of times it ended up in each of the source memory categories of interest for the current investigation. Bottom subsection indicates proportion of responses for each source memory judgment out of total recognition hits (collapsing across high and low confidence levels). Section title: Response times: Is context familiarity behaviorally dissociable from recollection and item-familiarity? Educational score: 4.027027130126953 Domain: biomedical Document type: Study Language: en We analyzed only subjects who had provided pairwise responses in each of the six conditions of interest ( N = 38). In our paradigm, participants first made a recognition judgment immediately followed by a source memory judgment for each item ; we separately assessed the response times for the item and source judgments ( Table 2 ). Table 2 Descriptive statistics of response time (ms) for item and source memory judgements Item Memory Source Memory Condition M SD SE M SD SE Recollection 1810 422 068 2596 1126 182 Context Familiarity 2710 962 156 2075 0968 157 Item Familiarity 2361 684 111 2612 1577 255 Time is reported in milliseconds, and data represents the sample of participants with pairwise observations included in the reported results ( N = 38). Section title: Response times: Is context familiarity behaviorally dissociable from recollection and item-familiarity? Educational score: 4.163872718811035 Domain: biomedical Document type: Study Language: en First, in item recognition judgments, reaction times were assessed across the factor of the three memory conditions (recollection, context familiarity, and item familiarity), using the same low confidence source memory responses in recollection and context familiarity conditions as was done in prior studies, 1 since it held constant the variable of source memory confidence. Response times for the three memory conditions were subjected to a one-way repeated measures ANOVA with three levels, which revealed a significant main effect of condition (F(2,37) = 25.16, p < 0.001, n 2 p =0 .41). Post hoc pairwise comparisons using the Bonferroni correction revealed that responses significantly differed for item familiarity and context familiarity, such that context familiarity was responded to reliably slower than item familiarity (MD = 348.57 msec, p = 0.048, 95% CI [2.26, 694.88], Cohen’s d = 0.48, as well as recollection (MD = 900.15 msec, p < 0.001, 95% CI , Cohen’s d = 0.76) . Item familiarity responses were also slower than recollection (MD = 551.58 msec, p < 0.001, 95% CI [297.97, 805.19], Cohen’s d = 1.24). Figure 2 Reaction speeds for item recognition and source memory judgments Mean times in milliseconds are shown in black with standard error of the mean for responses of item recognition (left) and source memory judgments (right), for three different conditions of memory response patterns, N = 38. Green: item familiarity (iFam.), operationalized as retrieval of recognition hits that did not have source memory (received responses of “source unknown”). Blue: context familiarity (cFam.), operationalized as retrieval of low-confidence item recognition that had correct source memory responses. Red: recollection (Rec.), operationalized as retrieval of high-confidence item recognition that had correct source memory responses. The boxplots demonstrate the median value, notches (95% confidence interval), and interquartile range (IQR) with lower and upper whiskers (Q1-1.5∗IQR; Q3+1.5∗IQR). The violin plots show density curves centered around the median value. Plots were generated using the scripts created by. 68 Section title: Response times: Is context familiarity behaviorally dissociable from recollection and item-familiarity? Educational score: 4.074465274810791 Domain: biomedical Document type: Study Language: en Within source memory judgments, response times for the three memory conditions revealed a significant main effect of condition (F(1.51,55.81) = 8.28, p = 0.002, n 2 p = 0.18). Further investigation using post hoc tests with Bonferroni correction revealed that source memory judgments for context familiarity responses were faster than those for both recollection and item familiarity (MD = 521.06, p < 0.001, 95% CI [ 273.01, 769.10], Cohen’s d = 0.42; MD = 537.21, p = 0.012, 95% CI [100.20, 974.23], Cohen’s d = 0.43). . Response times during source memory judgments for recollection and item familiarity conditions did not differ (MD = 16.16, p = 1.00, 95% CI [−399.64, 431.96], BF 01 = 5.70). Section title: Response times: Is context familiarity behaviorally dissociable from recollection and item-familiarity? Educational score: 4.047387599945068 Domain: biomedical Document type: Study Language: en Because item- and context-familiarity conditions also differed in recognition confidence , it was possible that differences between item- and context-familiarity conditions could have been attributable to the high confidence (‘5’) recognition responses included in the item familiarity condition. To test this directional hypothesis, we conducted a targeted analysis of these conditions while using only “low confidence recognition (‘4’) with source unknown” (item familiarity Low, no source memory responses), and low confidence recognition with source correct (context familiarity Low , all correct source memory responses). (Authors thank an Anonymous Reviewer for suggesting this valuable control analysis). While this excluded high-strength item-familiarity responses (high confidence recognition responses of ‘5’), such that a null finding would not be able to falsify the hypothesis, it nevertheless represented a valuable challenge of the alternative hypothesis using only weaker-strength item familiarity matched for item-familiarity strength. 18 , 20 , 21 , 33 , 69 Since these control analyses’ conditions were specifically defined by removing response types and thereby inherently weakening its power to detect differences, they nevertheless still produced significant results, and they also went on to be mirrored by similar results in the physiological measurements. Section title: Response times: Is context familiarity behaviorally dissociable from recollection and item-familiarity? Educational score: 4.1002984046936035 Domain: biomedical Document type: Study Language: en The reliable difference originally observed between item- and context-familiarity responses was still preserved (t(36) = 2.09, p = 0.022, one-tailed, Cohen’s d = 0.34 95% CI [-inf, −49.49]; cFam Low : M = 2703, SD = 1033, SE = 149; iFam Low : M = 2896, SD = 852, SE = 140), and maintained a comparable pattern for source memory responses as were seen in the main analysis above (t(36) = 1.94, p = 0.030, one-tailed, Cohen’s d = 0.32, 95% CI [-inf, 57.76]; iFam Low : M = 2418, SD = 1697, SE = 279). These findings ensured that differences between familiarity responses (context, item) were not confounded by inclusion of higher confidence levels of memory strength in the item familiarity condition. Section title: Electrophysiological results Educational score: 4.049281120300293 Domain: biomedical Document type: Study Language: en The EEG analyses began with an assessment of general memory ERPs (hits vs. correct rejections) to identify if, consistent with the behavioral findings, there were three different physiological patterns of activation supporting episodic memory retrieval. This adopted the same approach as originally taken to characterize the conventional dual processes of recollection and familiarity 46 , 70 but was applied here to three different locations and latencies selected based upon hypotheses from prior findings. 1 , 22 This was then followed by a series of more specific analyses of the particular memory condition contrasts. Section title: Electrophysiological results Educational score: 4.202432632446289 Domain: biomedical Document type: Study Language: en For the first analysis, we used a basic contrast of measuring ERPs for hits vs. correct rejections in every subject ( N = 54) using a priori predictions from the same sites as the previous reports 1 , 22 : mid-central site Cz from 400 to 600 ms for the FN400, left parietal site P3 from 600 to 900 ms for the LPC, and fronto-central site Fc1 from 800 to 1200 ms for the BCN. These ERPs were subjected to a 2 × 3 × 3 repeated measures ANOVA with factors being memory, time, and site. Results revealed main effects of site (F(1.20, 53) = 46.71, p < 0.001, n 2 p = 0.47) and time (F(1.6, 53) = 13.271, p < 0.001, n 2 p =0 .20) and, importantly, a significant 3-way interaction of memory x site x time (F(2.29, 53) = 20.018, p < 0.001, n 2 p =0 .27) [in addition to interactions of memory x site (F(1.57, 53) = 13.60, p < 0.001, n 2 p = 0.20), memory x time (F(1.61, 53) = 22.89, p < 0.001, n 2 p =0 .30) and site x time (F(1.75, 53) = 14.58, p < 0.001, n 2 p = 0.22) . Figure 3 Old-new effects of recognition memory Top panel: Topographic maps depicting memory effects of the subtraction of hits minus correct rejections, N = 54; color scale of topographic maps denotes amplitude differences from −2 to 2 mu-volts. Maps are plotted for each of the three time latencies of 400–600 ms (ms), 600 to 900 ms, and 800 to 1200 ms that have been associated with the frontal negative old-new effect (FN400), late parietal component (LPC), and later broad central negativity (BCN), respectively. White boxes denote the sites from the topographic maps that are shown for the corresponding ERP figures beneath the maps, as well as where statistical analyses were performed. Bottom panel: Event-related potential (ERP) amplitudes (μV) of the individual conditions of recognition hits (dashed line) and correct rejections (solid line) plotted through the 1200 ms epoch and beginning with a −200 ms baseline period. Shaded areas depict the standard error or the mean for each condition. Section title: Electrophysiological results Educational score: 4.217223167419434 Domain: biomedical Document type: Study Language: en Consistent with our a priori directional hypotheses, hits were more positive than correct rejections at Cz from 400 to 600 ms (i.e., an FN400 effect; t(53) = 3.86, p < 0.001, one-tailed, Cohen’s d = 0.53, 95% CI [0.47, inf]; Hit: M = −3.66, SD = 3.51, SE = 0.48; CR: M = −4.50, SD = 3.72, SE = 0.51) and at P3 from 600 to 900 ms (an LPC effect; t(53) = 3.10, p = 0.002, one = tailed, Cohen’s d = 0.42, 95% CI [0.38, inf], Hit: M = 3.46, SD = 2.54, SE = 0.346; CR: M = −0.430, SD = 2.28, SE = 0.310), but were more negative at fronto-central site Fc1 from 800 to 1200 ms (t(53) = 2.84, p = 003, one-tailed, Cohen’s d = 0.39, 95% CI -[inf, −0.348]; Hit: M = −3.86, SD = 3.31, SE = 0.451; CR: M = −3.01, SD = 3.28, SE = 0.45) with comparable results also evident from 800 to 1200 ms at adjacent site Cz, t(53) = 2.50, p = 0.007, one-tailed, Cohen’s d = 0.34, 95% CI [-inf, −0.242]; Hit: M = −2.27, SD = 3.08, SE = 0.42; CR: M = -1.54, SD = 3.11, SE = 0.423). These findings provide strong support for three dissociable neural signals underlying basic episodic recognition, operating in different times and places on the scalp. 46 , 47 , 59 , 71 , 72 , 73 , 74 A series of subsequent analyses were then carried out to systematically characterize each condition (context familiarity, recollection, and item-familiarity) as compared to correct rejections, 46 , 48 , 70 described below. Section title: Experiment 1: Verifying if recollection and context familiarity exhibit different neural correlates Educational score: 4.159933567047119 Domain: biomedical Document type: Study Language: en Since the current project hypothesized that context familiarity is distinct from recollection, we first sought to establish that the dataset validly reproduced prior findings 1 before endeavoring to explore differences within familiarity of items and context. A sample of N = 27 subjects provided observations in both conditions of interest for this analysis and satisfied inclusion criteria for numbers of valid ERP trials (see Method). A 2 × 3 × 2 repeated measures ANOVA for factors of memory condition (recollection, context familiarity), time interval , and site (P3, Cz) was performed based upon a priori predictions derived from the preceding analyses and prior reports dissociating context familiarity from recollection-based processing. 1 Results revealed a significant main effect of memory condition (F(2,26) = 9.418, p = 0.005, n 2 p = 0.27), a main effect of time interval (F(1.138, 26) = 6.262, p = 0.015, n 2 p = 0.19), and a main effect of site (F(1,26) = 15.89, p < 0.001, n 2 p = 0.38), along with a significant time by site interaction (F(1.35, 26) = 18.81, p < 0.001, n 2 p =0 .42) and a memory x time × site interaction (F(1.5), 26 = 7.69, p = 0.002, n 2 p = 0.23) . Figure 4 Three physiological effects of episodic memory retrieval Left panels: Topography maps are shown for each memory condition as compared to correct rejections in Experiment 1: (top) high-confident item recognition judgments that also had correct source memory retrieval, N = 27; (middle) low-confident item recognition judgments of that also had correct source memory retrieval, N = 27; and (bottom) recognition hits (collapsed across both high and low confidence) that did not have source memory retrieved (received responses of “source unknown”), N = 19. Color scale of topographic maps denotes amplitude differences for each condition as compared to correct rejections, ranging from −2 to 2 mu-volts. Right panels: Event-related potential (ERP) amplitudes (μV) from representative sites of maximal activation for each of the respective effects during the memory retrieval epoch of −200 to 1200 ms (ms); shaded areas for each plot represent the standard error of the mean. Section title: Experiment 1: Verifying if recollection and context familiarity exhibit different neural correlates Educational score: 4.253626823425293 Domain: biomedical Document type: Study Language: en ERPs for context familiarity compared to the conventional ERP control condition of correct rejections revealed reliable evidence of the same negative-going effect from 800 to 1200 ms that had been directionally hypothesized from previous reports 1 , 22 , while also reproducing the prior findings of there being no evidence for ERP correlates of recollection or familiarity (LPC, FN400). 1 ERPs for context familiarity were more negative-going than correct rejections (CR) from 800 to 1200 ms at mid central site Cz (t(26) = −2.53, p = 0.009, one-tailed; Cohen’s d = 0.49, 95% CI [-inf, −0.369]; cFam: M = −2.91, SD = 3.575, SE = 0.69; CR: M = −1.772, SD = 3.72, SE = 0.72). Alternatively, there was no LPC effect evident for context familiarity from 600 to 900 ms (t(26) = 0.161, p = 0.437, one-tailed; Cohen’s d = 0.03, 95% CI [-0.732, inf, BF 01 = 4.32]; cFam.: M = −0.857, SD = 3.00, SE = 0.58; CR: M = −0.932, SD = 2.15, SE = 0.413), nor any evidence for an FN400 effect for context familiarity from 400 to 600ms (t(26) = −0.056, p = 0.522, one-tailed, Cohen’s d = 0.01, 95% CI [-0.753, inf]), BF 01 = 5.12; cFam: M = −5.241, SD = 3.83, SE = 0.737; CR: M = −5.217, SD = 4.03, SE = 0.78). Section title: Experiment 1: Verifying if recollection and context familiarity exhibit different neural correlates Educational score: 4.290270805358887 Domain: biomedical Document type: Study Language: en ERPs for the recollection condition were also found to be consistent with the prior findings 1 when compared to correct rejections : eliciting both an FN400 effect at Cz from 400 to 600ms, (t(26) = 2.82, p = 0.004, one-tailed, Cohen’s d = 0.54, 95% CI [0.487, inf]; rec: M = −3.939, SD = 3.54, SE = 0.68; CR: M = −5.22, SD = 4.03, SE = 0.78) and an LPC at left parietal site of P3 from 600 to 900ms (t(26) = 2.98, p = 0.003, one-tailed, Cohen’s d = 0.57, 95% CI [0.665, inf]; rec: M = 0.627, SD = 2.94, SD = 0.57; CR: M = −0.932, SD = 2.15, SE = 0.41) but no evident differences during the later time of 800–1200 ms (t(26) = 0.002, p = 0.499, one-tailed; Cohen’s d = 0.00, 95% CI = [−0.923, inf], BF 01 = 4.91). These results indicated that the neurophysiology for conditions of recollection and context familiarity were indeed distinct in time and place on the scalp. Overall, these results thus reproduced the prior findings that neural processing for the retrieval of familiar contexts was distinct from recollection, 1 and established the foundation for exploring if the context familiarity may also be directly dissociable from item familiarity. Section title: Experiment 1: Verifying if recollection and context familiarity exhibit different neural correlates Educational score: 4.271453857421875 Domain: biomedical Document type: Study Language: en ERPs for the item familiarity condition also reliably exhibited their predicted effects of an early old-new effect from 400 to 600 ms, maximal at site Cp1 ( N = 19, t(18) = 2.02, p = 0.029, one-tailed, Cohen’s d = 0.46, 95% CI [0.160, ∞]; iFam: M = −1.32, SD = 3.47, SE = 0.797; CR: M = −2.47, SD = 2.57, SE = 0.59), providing concurrent validity with similar other findings of posterior distributions attributed to absolute familiarity. 75 , 76 , 77 The condition did not exhibit any evidence for an LPC from 600 to 900 ms at P3 (t(18) = 1.22, p = 0.119, one-tailed, Cohen’s d = 0.28, 95% CI [−0.238, ∞], BF 01 = 1.27; iFam: M = −5.45, SD = 3.49, SE = 0.802; CR: M = −1.11, SD = 2.37, SE = 0.543) nor any later negative effect from 800 to 1200 ms at Cz (t(18) = 0.910, p = 0.187, one-tailed, Cohen’s d = 0.21, 95% CI [∞, 0.576], BF 01 = 1.83; iFam: M = −1.93, SD = 3.60, SE = 0.83; CR: M = −1.29, SD = 2.92, SE = 0.67). Together, the consistent findings of distinct ERP effects of an FN400, LPC, and BCN among both the established general conditions (Hits vs. CR) and the more specific conditions of response combinations (iFam, cFam, Rec., each vs. Cr.) provided convergent validity of similar findings observed from different measures, while also demonstrating concurrent validity of the newer specific ERP measures of memory processing with the more established general ERP measures of memory processes. Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.201850414276123 Domain: biomedical Document type: Study Language: en To test whether the context familiarity condition reflected the same or different kind of familiarity processing as traditional item-familiarity, we investigated if the two conditions varied during the conventional time window traditionally reported for familiarity-based processing of the FN400 (300–500 ms 46 , 47 ), performing a within-subjects ( N = 11) targeted analysis on mid-central site Cz where prior analysis identified peak activation for these conditions in both the present and prior study 1 that predicted a one-directional difference of context familiarity being more negative than item familiarity. ERPs for context familiarity were revealed to be significantly more negative than those for item familiarity (t(10) = −2.57, p = 0.015, one-tailed, Cohen’s d = 0.76, 95% CI [-inf, −0.622]; cFam: M = −4.62, SD = 3.32, SE = 0.70; iFam: M = −2.42, SD = 3.22, SE = 1.33; Figure 5 A), and topographies indicated a broad negative-going distribution of this effect across central scalp sites and throughout the epoch. To assess if these effects varied throughout the epoch a 2x3 ANOVA was performed using factors of memory condition (item familiarity, context familiarity) and time interval . Results revealed a marginal main effect of memory (F(1, 10) = 4.251, p = 0.066, n 2 p = 0.298, Cohen’s d = 0.65), a significant main effect of time (F(1.18, 10) = 5.13, p = 0.039, n 2 p = 0.339), and no memory × time interaction (F(1.34, 10) = 1.48, p = 0.255). Figure 5 Within-subjects ERP differences of context familiarity and item familiarity Results depict findings from Experiment 1. (A) within-subject effects for participants who shared pairwise response trials in both conditions of item familiarity and context familiarity ( N = 11; note: N = subjects, n = trials, see Methods section 2.3.2). Effects were evident at 300–500 ms and distributed broadly across the scalp while being maximal over central midline site Cz. Topographic maps of difference waves for effects results from the subtraction of item familiarity from context familiarity conditions, respectively, with color scale depicting difference amplitudes from −2 to 2 mu-volts; white boxes denote regions of peak activity and targeted analyses; time intervals for each topography map is noted beneath it in milliseconds (ms). Shaded areas of event-related potentials (ERPs) depict the standard error or the mean for each condition. (B) Results from a sample of participants ( N = 25) meeting a lower inclusion criterion for signal-to-noise ratio ( n = 5 artifact-free ERP trials pairwise). (C) Control analysis of the same conditions but while holding constant the variable of item recognition confidence (depicting results from only the low confidence ratings of ‘4’ for each condition, and excluding the high confidence ‘5’ responses from item familiarity, N = 3, n > 11). Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.0950164794921875 Domain: biomedical Document type: Study Language: en To test if these results could be attributable to the potential confound of high confidence recognition responses included in the item familiarity condition, we sought a similar control test as was described for the behavioral data of response times: by removing the high-confidence responses from the item-familiarity condition so that it was matched to the low-strength responses of the context familiarity condition (Authors thank an anonymous Reviewer for suggesting this valuable analysis). ERPs for this contrast were available from only a limited sub-sample of the primary dataset due to there being only N = 3 participants available meeting our strict a priori inclusion criteria of the “item4+source unknown” item familiarity condition 67 (see Methods section 2.3.1) (though we note that the present paradigm has repeatedly been shown in prior studies to be effective and sensitive to detecting reliable differences in similar small sample sizes of specialized clinical patients on ERP measures of familiarity, confidence, and implicit memory repetition effects, 18 , 22 , 78 in addition to conditions of metacognition, 67 and that subsequent analyses conducted in Experiment 2 obtained the same results using a larger sample size of N = 12 in an independent dataset). Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.145352840423584 Domain: biomedical Document type: Study Language: en We used a directional t-test based upon the hypothesis that context familiarity exhibits more negative-going ERPs than item familiarity at the same mid-central size (Cz) and time (300–500 ms) that was found in the primary analysis . Despite the limited sample, ERPs for context familiarity Low remained more negative than those for item familiarity Low : while this difference was not initially significant from 300 to 500 ms (t(2) = 1.67, p = 0.119, one-tailed, Cohen’s d = 0.962, 95% CI [-∞, −1.37], BF 01 of 0.610; iFam: M = −1.67, SD = 3.99, SE = 2.30; cFam: M = −3.49, SD = 2.19, SE = 1.27) there was a significant effect maintained in the nearly-identical time interval of 400–600 ms that has also been commonly used for measuring the FN400 in prior studies using this specific dataset 18 , 67 : (t(2) = 5.57, p bonf = 0.015, one-tailed, corrected, Cohen’s d = 3.21, 95% CI [-∞, −1.5]; iFam: M = −1.36, SD = 2.38, SE = 1.38, values: −3.29, −2.03, 1.31; cFam: M = −4.51, SD = 1.54, SE = 0.89, values: −5.40, −5.404, −2.73) , indicating that the main effect was preserved in the more stringent control analysis. Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.243963241577148 Domain: biomedical Document type: Study Language: en Since we used a relatively conservative criteria for inclusion of participants in the within-subjects analysis ( n = 12 artifact-free ERP trials pairwise, see Method), it provided a rigorous threshold to foster better signal-to-noise ratio of ERP effects but also resulted in a fairly small sample ( N = 11). Therefore, we also performed a parallel analysis with a more liberal inclusion criteria for subjects, (Authors thank an Anonymous Reviewer for suggesting this valuable control analysis) which could increase the sample size and challenge the findings via testing them with reduced signal-to-noise ratio. 79 , 80 The same results persisted when lowering the trial inclusion criteria to n = 5, which provided a larger sample of N = 25 subjects: ERPs for context familiarity still exhibited a negative difference from ERPs of item familiarity that was maximal at adjacent site Fc1 and extending broadly across bilateral mid-central regions . We used a similar 2x3 ANOVA as employed in the primary analysis, using factors of memory condition (item familiarity, context familiarity) and adjacent time interval , and like the primary results using the more conservative inclusion criteria with a smaller sample, there was a main effect of memory (F(1, 24) = 4.37, p = 0.047, n 2 p = 0.15, Cohen’s d = 0.42) with no significant evidence for effects of time nor a memory × time interaction (both F’s < 1), indicating that ERPs for context familiarity were again significantly different from item familiarity beginning early in the epoch and persisting throughout despite lower signal-to-noise ratio. 79 , 80 Overall, the convergence of findings indicated that ERPs for item familiarity and context familiarity differed reliably during the traditional time window of familiarity processing, and thus that these two memory conditions represented reliably different kinds of familiarity processing on a trial-wise level within subjects. 46 , 47 , 59 , 71 , 72 , 73 , 74 Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.100672721862793 Domain: biomedical Document type: Study Language: en As the preceding analysis demonstrated moment to moment differences of modular cognitive processes within the same individuals over time, we next sought to determine if these patterns would persist as individual characteristics across individuals. 67 The within-subjects approach used above required paired observations in both conditions of infrequent memory response patterns; however, the two conditions of item-familiarity and context-familiarity tend not to co-occur often within subjects. That is, those who tend to retrieve source memory well (i.e., better performers) also rarely report lacking source information (lesser memory), and those who tend to fail retrieving source memory do not also frequently report retrieving it. We thus utilized a between-subjects approach that treated those with sufficient trials in one condition but not the other as separate groups, in a mutually independent way (total sample of N = 26; item familiarity group: N = 9, context familiarity group = 17). This resulted in the exclusion of those from the within-subject analysis, but nevertheless converged to provide the same findings with an entirely different subset of participants, despite the inherent challenges to the hypothesis from a smaller sample. Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.179452896118164 Domain: biomedical Document type: Study Language: en Using a between-groups t-test, the same pattern of ERPs persisted between subjects from 300 to 500 ms such that ERPs for context familiarity were significantly more negative-going than from item familiarity (t(24) = 2.82, p = 0.005, one-tailed, Cohen’s d = 1.16, 95% CI [1.93, inf], Figure 6 A), (cFam: N = 17, M = −4.62, SD = 4.63, SE = 1.23; iFam: N = 9, M = 0.250, SD = 3.34, SE = 1.12), and was not statistically significant during the later time intervals (600–900 ms: t(24) = 1.21, p = 0.119, one-tailed; 95% CI [−0.698, inf], BF 01 = 1.57; 800–1200 ms: t(24) = 0.664, p = 0.257, 95% CI [−1.72, inf], BF 01 = 2.27). Overall, this mirrored the results from the preceding within-subjects analysis, independently demonstrating that these are distinct physiological patterns for familiar memory responses both at the single trial level (within-subjects) and at the level of individual variability (between-subjects), and that the context familiarity condition cannot be attributed to merely a form of the same kind of familiarity process supporting familiarity of item recognition. Figure 6 Between-subjects ERP differences of context familiarity and item familiarity (A) Top: Between-subject effects in independent sub-groups of participants who had response trials in one condition but not the other (i.e.,: mutually exclusive N = 26 total; item familiarity: N = 9, context familiarity: N = 17), from Experiment 1. 18 , 67 Event-related potentials (ERPs) are shown from representative midline central site Cz; Shaded areas of event-related potentials (ERPs) depict the standard error or the mean for each condition. Bottom: range-normalized topographic maps of individual conditions from 300 to 500 ms, with color scale depicting voltage on the numerical scales indicated. (B) Between-subjects effects from participants of Experiment 2, 1 , 19 ( N = 24 total; item familiarity: N = 13, context familiarity: N = 11). Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.111010551452637 Domain: biomedical Document type: Study Language: en Control analyses of range-normalized values revealed that the group differences between the memory conditions were not attributable to scaling artifacts or cohort effects that might be operating independent of the memory conditions. Since it is possible that the results of the between-subjects analyses could be driven in part by group-level differences in overall magnitudes of the ERP amplitudes between the ‘cohorts’ (e.g., scaling artifacts, 81 , 82 , 83 , 84 ; we conducted follow-up analyses to control for this possibility. We range-normalized the ERP amplitudes of the individual conditions within each group for item-familiarity and context-familiarity, respectively . This approach serves to overcome potential scaling artifacts of differential amplitudes, as it normalizes the ERPs in the dimension of amplitude magnitude and allows for investigation of where they are spatially located 46 , 73 , 84 as has been done in prior work. 18 , 46 , 85 Section title: Are the neural correlates of context familiarity different from item familiarity? Educational score: 4.222688674926758 Domain: biomedical Document type: Study Language: en Results from this control analysis revealed that range-normalized values for item- and context-familiarity ERPs remained significantly different from 300 to 500 ms at mid-central site Cz (t(24) = 2.36, p = 0.027, Cohen’s d = 0.97, 95% CI [-1.24, −0.084]; iFam: N = 9, M = 0.75, SD = 0.64, SE = 0.21; cFam: N = 17, M = 0.096, SD = 0.69, SE = 0.17) , and thus that the differences between the memory conditions were not attributable to scaling artifacts or cohort effects of groups that might be operating independent of the memory conditions. Collectively, these findings indicated that the observed differences in familiarity response types reflected differential neural processing at the individual subject level of variability, in addition to the trial-wise nature of the memory processing that was identified in the preceding within-subject analyses. These results thus converge to reveal that the two conditions represent fundamentally different kinds of familiarity operating in service of episodic recognition. Section title: Results: Experiment 2 Educational score: 4.103916645050049 Domain: biomedical Document type: Study Language: en If there are differential neural correlates of context familiarity and item familiarity operating as distinct processes of episodic memory, then the differences should be evident in other, independent experiments. Therefore, we assessed questions of reproducibility and sought validity of the findings through replication. 86 , 87 , 88 We investigated if the differences between ERPs for context familiarity and item familiarity could be reproduced among independent datasets that were aggregated from three previously-published studies using a nearly-identical paradigm and which had previously reported both traditional ERP correlates of item familiarity as well as ERP effects of context familiarity being separately dissociated from those of recollection, but had not directly contrasted conditions of item-familiarity to context-familiarity. 1 , 19 , 22 Section title: Results: Experiment 2 Educational score: 4.08350133895874 Domain: biomedical Document type: Study Language: en The analyses of Experiment 2 were conducted using the same sites and latencies that had been reported as representative of effects in the present and previous studies (mid-central Cz; bilateral frontal sites F3, F4 1 , 22 ). The null hypothesis for these analyses is that ERPs for the two conditions of context- and item-familiarity would exhibit no differences, if in fact the two memory responses were being supported by the same kind of underlying memory processing, and/or if the main results of Experiment were representing a form of type I error. The alternate hypothesis was that context familiarity would exhibit more negative-going ERPs than item-familiarity, and that if there is any such difference in ERP activity for the two conditions then it would be indicative that the two memory response types could not be measuring the same kind of memory process, and thus reflecting different kinds of memory processing people were using to making these different memory judgments. 6 , 21 , 42 , 46 , 47 , 48 Section title: Experiment 2: Within-subjects familiarity Educational score: 4.135581016540527 Domain: biomedical Document type: Study Language: en First, we assessed if the within-subjects results observed between item familiarity and context familiarity in Exp. 1 could be seen at the mid-central site of Cz, using a 2x3 ANOVA with factors of memory (context familiarity, item familiarity) and time . This revealed that there was a significant main effect of memory (F(1,19) = 4.55, p = 0.046, n 2 p = 0.193, Cohen’s d = 0.48), a main effect of time (F(1.26, 19) = 19.72, p < 0.001, n 2 p = 0.509), but no significant memory × time interaction (F(1.68, 19) = 0.437, p = 0.616, n 2 p = 0.022) . These findings indicated that the two conditions differed reliably at the mid central site throughout the epochs from 300 to 1200 ms, and represented a faithful reproduction of the differences originally observed between ERPs for context- and item-familiarity in the present study’s main findings . Figure 7 Independent replication of ERP differences for context- and item-familiarity Within-subject effects for participants sharing pairwise response trials in both conditions of item familiarity and context familiarity ( N = 20) in Experiment 2 data aggregated from previously published studies 1 , 19 , 22 (see Method). (A) Top row: topographic difference maps of the resulting within-subjects difference between context familiarity minus item familiarity, in time intervals shown in milliseconds (ms). Color scale depicts difference amplitudes from −2 to 2 mu-volts, white boxes denote regions of targeted analyses revealing statistically significant effects. ERPs from representative sites Cz (mid-central), F3 (left frontal), and F4 (right frontal); shaded areas depict the standard error or the mean for each condition. (B) Same contrast as depicted as in (A) but excluding high confidence recognition responses from the item familiarity conditions , to match conditions on item recognition confidence levels ( N = 12). Section title: Experiment 2: Within-subjects familiarity Educational score: 4.119271278381348 Domain: biomedical Document type: Study Language: en Because the previous datasets 1 , 22 had reported the ERP effects for context familiarity also manifesting at bilateral fronto-central sites, we expanded the aforementioned analyses to also include the frontal sites F3 and F4, using a 2 × 3 × 3 ANOVA. This analysis continued to provide a faithful replication of the original findings of the present work, as there was a main effect of memory (F(1,19) = 6.69, p = 0.018, n 2 p = 0.261, Cohen’s d = 0.49), an effect of time (F(1.29, 19) = 9.69, p = 0.003, n 2 p = 0.338), and a site × time interaction (F(2.24, 19) = 15.20, p < 0.001, n 2 p = 0.444) as the previously-reported frontal sites became more pronounced later in the epoch . Importantly, these results provide an independent replication of the critical findings reported in the present study comprised of entirely different participants from a different laboratory (the UC Davis Dynamic Memory Lab vs. California State University – San Bernardino, using different EEG hardware. Thus, the results of Experiment 1 in the main text of the present study are bolstered as valid, reliable findings observed across diverse participants from four different independent experiments. 1 , 19 , 22 , 67 Section title: Experiment 2: Controlling for confounds of confidence levels in item familiarity Educational score: 4.032081127166748 Domain: biomedical Document type: Study Language: en One possible alternative interpretation of the ERP differences we observed between the conditions of item familiarity and context familiarity is that they could have been confounded by inclusion of high confidence recognition trials in the item familiarity condition. That is, the conditions of item- and context familiarity also vary on the factor of item recognition confidence, since the item familiarity condition includes both high and low confidence responses of strong and weak item familiarity levels, whereas the context familiarity condition contains only the low confidence recognition judgments that had correct source memory. One approach to address this issue is to exclude the high confidence responses from the item familiarity condition, (Authors thank an Anonymous Reviewer for suggesting this valuable control analysis) even though, as noted in Experiment 1, the context familiarity condition could still differ from strong forms of item familiarity that were excluded from the analysis. 29 , 32 , 33 This control analysis was performed in the behavioral results reported in Experiment 1 and was found to successfully preserve the findings that the conditions for item- and context-familiarity were reliably distinct in response times. Section title: Experiment 2: Controlling for confounds of confidence levels in item familiarity Educational score: 4.107863903045654 Domain: biomedical Document type: Study Language: en For the ERP version of this control analysis in Experiment 1, there was only a small sample ( N = 3) meeting our inclusion criteria for ERPs of pairwise comparisons of the item familiarity condition with context familiarity that still provided a significant effect, but would benefit from an independent replication in a larger sample. In Experiment 2 there were more participants available ( N = 12). We thus assessed ERPs for “item4+source unknown” (iFam Low .) vs. ‘item4+source correct’ (cFam.), using a directional t-test based upon the a priori hypothesis derived from the prior findings in Experiment 1 that context familiarity exhibits more negative-going ERPs than item familiarity at the same mid-central size (Cz) and time (300–500 ms) as was found in Experiment 1. This revealed that there were still significant effects (t(11) = 1.97, p = 0.037, one-tailed, Cohen’s d = 0.60, 95% CI [-∞, −0.101]; iFam: M = −0.849, SD = 2.74, SE = 0.79; cFam: M = −1.99, SD = 2.06, SE = 0.593), and thus the main finding was replicated again and with a larger sample than original finding in Experiment 1. Thus, the inclusion of the high confidence recognition responses in the condition of item familiarity is not contaminating nor confounding the results we observed of reliable differences between item- and context-familiarity . Section title: Experiment 2: Between subjects familiarity Educational score: 4.106620788574219 Domain: biomedical Document type: Study Language: en The between-subjects ERP effects from Exp. 1 were also reproduced when aggregating across participants from prior studies 1 , 19 . As was done in the main results, participants were included in conditions of either item familiarity or context familiarity if they met the trial inclusion criterion of sufficient trial responses ( n = 12) in exclusively one condition but not the other, and these were entirely different participants than those included in the within-subjects analysis described above. This resulted in a subgroup of N = 13 for the item familiarity condition, and N = 11 for context familiarity. As familiarity effects for these prior studies were reported for 400 to 600 ms, 1 , 22 a targeted analysis was conducted during this latency to assess if context familiarity ERPs exhibited the same negative-going difference from item-familiarity ERPS at the mid-frontal site characteristic of previous familiarity effects reported in these participants 1 , 19 (Fz). A between-group t-test revealed the ERPs to reliably differ (t(22) = 1.923, p = 0.034, one-tailed, Cohen’s d = 0.79, 95% CI [-∞, −0.426]), with ERPs for context familiarity again being more negative-going than those for item-familiarity ( N = 11, M = −2.69, SD = 4.98, SE = 1.50; N = 13, M = 1.25, SD = 5.00, SE = 1.39, respectively). Section title: Experiment 2: Within-subjects memory condition effects Educational score: 4.145424842834473 Domain: biomedical Document type: Study Language: en Next, the results of each individual condition’s memory effect were compared to correct rejections, as was done in Figure 4 of the main findings of Exp. 1. ERP correlates of context familiarity again exhibited a reliable effect from 800 to 1200 ms ( N = 33) that was distributed broadly across the central-posterior scalp and maximal at site Cp1 (t(32) = −3.22, p = 0.003, Cohen’s d = 0.56, 95% CI [−3.17, 7.12]; cFam: M = 1.84, SD = 4.35, SE = 0.76; CR: M = 3.78, SD = 3.94, SE = 0.69), but for which there was no significant FN400 effects evident from 400 to 600 ms (t(32) = 0.163, p = 0.113, 95% CI [−0.195, 1.75], BF 01 = 1.25; cFam: M = −0.006, SD = 4.24, SE = 0.74; CR: M = −0.782, SD = 3.84, SE = 0.67), nor any evident LPC at P3 from 600 to 900 ms (t(32) = 1.07, p = 0.293, 95% CI [−1.66, 0.515], BF 01 = 3.17); cFam: M = 2.19, SD = 4.42, SE = 0.77; CR: M = 2.76, SD = 3.66, SE = 0.64) . This finding reproduced and confirmed the Exp. 1 finding that context familiarity was associated with a broad central negative effect, that it held no evidence of association with the FN400 and provided an evidence for absence of the LPC effect. Figure 8 Physiological effects of episodic memory retrieval conditions Left panels: Topography maps are shown for each memory condition as compared to correct rejections in Experiment 2, comprising data from three previously published studies utilizing the same paradigm as the present study. 1 , 19 , 22 (top) High-confident item recognition judgments that also had correct source memory retrieval, N = 54; (middle) low-confident item recognition judgments of that also had correct source memory retrieval, N = 33; and (bottom) recognition hits (collapsed across both high and low confidence) that did not have source memory retrieved (received responses of “‘source unknown”), N = 38. Color scale of topographic maps denotes amplitude differences for each condition as compared to correct rejections, ranging from −2 to 2 mu-volts. Right panels: Event-related potential (ERP) amplitudes (μV) from representative sites of maximal activation for each of the respective effects during the memory retrieval epoch of −200 to 1200 ms (ms); shaded areas for each plot represent the standard error of the mean. Section title: Experiment 2: Within-subjects memory condition effects Educational score: 4.211060047149658 Domain: biomedical Document type: Study Language: en On the other hand, item familiarity was associated with significantly more positive ERPs than correct rejections at mid-central Cz from 400 to 600 ms ( N = 38) , reproducing the FN400 effect reported in Figure 4 of the main results section (t(37) = 3.77, p < 0.001, Cohen’s d = 0.61, 95% CI [−2.38, −0.715]; iFam: M = 0.362, SD = 3.78, SE = 0.61; CR: M = −1.18, SD = 3.79, SE = 0.62). During the later latencies of 600–900 ms and then 800 to 1200 ms associated with recollection and context familiarity, respectively, there were no reliable differences evident between the two conditions (t(37) = 0.95, p = 0.348, 95% CI [−1.44, 0.519], BF 01 = 3.76; iFam: M = 3.27, SD = 4.47, SE = 0.725; CR: M = 2.81, SD = 4.34, SE = 0.703); t(37) = 0.160, p = 0.877, 95% CI [-1.08, 0.923], BF 01 = 5.66; iFam: M = 3.49, SD = 4.39, SE = 0.71; CR: M = 3.41, SD = 4.19, SE = 0.68) , reproducing the same pattern of results reported in the present study’s main results . These findings indicated that the neurophysiological correlates of the item familiarity condition were linked with an FN400 effect but no comparable evidence for any LPC or BCN effects (and with Bayes Factor evidence of absence for each other effect, respectively), consistent with the well-established profile of item-familiarity ERPs observed within and across the two present Experiments and among the broader literature of other studies. 1 , 45 , 46 , 47 , 59 , 85 Section title: Experiment 2: Within-subjects memory condition effects Educational score: 4.218292236328125 Domain: biomedical Document type: Study Language: en Furthermore, similar to the findings of the present study, the recollection response condition exhibited both a reliable FN400 and LPC effect when compared to correct rejections ( N = 54), (t(53) = 6.14, p < 0.001, Cohen’s d = 0.84, 95% CI [1.43, 2.81]; Rec.: M = 0.207, SD = 4.92, SE = 0.668; CR: M = −1.915, SD = 4.53, SE = 0.61; t(53) = 4.73, p < 0.001, Cohen’s d = 0.64, 95% CI [0.942, 2.33]; Rec. M = 3.92, SD = 3.96, SE = 0.54), but provided no evidence for any BCN (t(53) = 0.585, p = 0.561, 95% CI [-1.55, 0.848], BF 01 of 5.72) . Collectively, these analyses of previously published datasets using the same memory paradigm as the present study provide a replication of the results observed in the current investigation. These patterns of effects reported here across both behavior and neurophysiology, both within and between subjects, and their replications among several other independent studies cannot be accounted for by a priori predictions from existing models of only a single- or dual processes of episodic memory. Figure 9 Old-new effects for recognition memory in Experiment 2 Data for Experiment 2 was aggregated from three previously published studies 1 , 19 , 22 ( N = 56). Top row: topographic difference maps of the resulting difference between hits minus correct rejections, plotted for each of the three time latencies of 400–600 ms (ms), 600 to 900 ms, and 1000 to 1400 ms that have been associated with the FN400, late parietal component (LPC), and late broad central negativity (BCN), respectively. Color scale depicting difference amplitudes from −2 to 2 mu-volts, white boxes denote regions of targeted analyses revealing statistically significant effects. Bottom panel: Event-related potential (ERP) amplitudes (μV) of individual conditions of recognition hits (dashed line) and correct rejections (solid line) plotted through the 1500 ms epoch and beginning with a −200 ms baseline period. Shaded areas depict the standard error or the mean for each condition. Section title: Experiment 2: Within-subjects old-new memory effects Educational score: 4.228521823883057 Domain: biomedical Document type: Study Language: en Using the same aggregated data also reproduced the other findings reported in the present study of a triple dissociation of ERP effects for item-familiarity, recollection, and context familiarity among the general memory contrast of hits minus corrections , whereby a 3-way interaction was originally found among an FN400, LPC, and BCN. For this analysis, we focused upon the latencies where effects had been observed in the prior studies for the FN400, LPC, and BCN (400–600 ms, 600 to 900 ms, 1000 to 1400 ms, respectively (Similar results were also found when assessing the time windows used in the present study of 400–600 ms, 600 to 900 ms, and 800 to 1200 ms: with main effects of memory F(1, 55) = 5.144, p = 0.027, n 2 p =0 .086, site (F(1.68, 55) = 7.70, p = 0.002, n 2 p = 0.123), time (F1.45, 55) = 44.797, p < 0.001, n 2 p = 0.449), and significant interactions of memory x time (F(1.41, 55) = 26.34, p < 0.001, n 2 p =0 .324), site x time (F1.56, 55) = 25.52, p < 0.001, n 2 p = 0.317), and a 3-way interaction of memory x site x time (F2.78, 55) = 4.66, p = 0.004, n 2 p = 0.078))), and focusing on sites Cz, P3, and Fc1 reported for effects in the present study ( N = 56). Results from a 2 × 3 × 3 ANOVA revealed that, similar to the main findings from Experiment 1 of the present study, there was no initial main effect of memory (F(1,55) = 2.19, p = 0.145, n 2 p = 0.038), but there were significant main effects of site (F(1.68, 55) = 5.82, p = 0.007, n 2 p = 0.096), and significant interactions of memory x time (F(1.52, 55) = 32.77, p < 0.001, n 2 p = 0.373), site x time (F(1.57, 55) = 23.59, p < 0.001, n 2 p = 0.300), plus a significant memory x site × time interaction (F(3.20, 55) = 4.77, p = 0.003, n 2 p = 0.080) . Section title: Experiment 2: Within-subjects old-new memory effects Educational score: 4.163850784301758 Domain: biomedical Document type: Study Language: en Consistent with the a priori hypotheses, results from directional t-tests based upon our a priori hypotheses revealed that there were significant effects of the FN400 (t(55) = 6.16, p < 0.001, one-tailed, Cohen’s d = 0.82, 95% CI [1.27, inf]; Hit: M = −0.208, SD = 4.39, SE = 0.588; CR: M = −1.95, SD = 4.48, SE = 0.599), LPC (t(55) = 3.06, p = 0.002, one-tailed, Cohen’s d = 0.41, 95% CI [0.402, inf]; Hit: M = 3.13, SD = 3.63, SE = 0.49; CR: M = 2.24, SD = 3.99, SE = 0.534), and BCN (t(55) = 1.85, p = 0.035, one-tailed, Cohen’s d = 0.25, 95% CI [-∞, −0.083]; Hit: M = 0.916, SD = 3.68, SE = 0.49; CR: M = 1.80, SD = 4.60, SE = 0.62). The BCN effect identified at the a priori selected location of Fc1 was observed to have extended broadly and been maximal at site Pz: t(55) = 4.33, p < 0.001, one-tailed, Cohens d = 0.58, 95% CI [-inf, −1.14], Together, these results revealed the same finding of a significant memory x site × time interaction in an independent dataset, effectively reproducing the original findings reported in the present study . Specifically, these results confirm that the three different memory effects are present within the most general measures of memory historically used in the field, in addition to the specific conditions described herein. Section title: Are the neural correlates of context familiarity reflecting non-conscious memory processing? Educational score: 4.128188133239746 Domain: biomedical Document type: Study Language: en While the responses given for context familiarity were defined as being explicit declarative responses from people for item recognition hits and also had overtly declarative correct source memory judgments, it nevertheless remained theoretically possible that they reflected a form of non-conscious processing such as that related to guessing from 100 to 300ms 89 or fluency that has been known to occur characteristically in earlier latencies of 200-400ms 85 , 90 , 91 for Review see. 76 Thus, to rule this possibility out, we sought to verify if the memory processing associated with the context familiarity condition’s effects in these participants was different from the hallmark signs of non-conscious, implicit memory signals that have been extensively characterized in the prior literature (i.e.,: recognition misses, 18 , 46 , 76 , 85 old items endorsed as 1 or 2 responses during the memory retrieval test). The null hypothesis of this analysis was that if the context familiarity condition was actually representing an implicit memory process, then it should show the same, or similar, activity as other implicit memory processing, such as the misses in the time windows when each effect is known to operate, respectively , and thus predict no significant differences in ERPs. Section title: Experiment 1: Misses Educational score: 4.262813568115234 Domain: biomedical Document type: Study Language: en We assessed ERPs for misses and context familiarity at the centro-parietal site of peak activity identified earlier for context familiarity (Cp1), using a within-subjects two-factor ANOVA with repeated measures on both factors ( N = 27). This analysis revealed no significant main effect of condition (F(1,26) = 1.03, p = 0.321, n 2 p = 0.038), identified a significant main effect of latency (F(1.91, 26) = 19.95, p < 0.001, n 2 p = 0.434), and importantly revealed a significant interaction of memory condition and latency (F(2.16, 26) = 3.78, p = 0.026, n 2 p = 0.127), which was further investigated with follow-up analyses . This revealed that ERPs for context familiarity were significantly more negative-going than misses at centro-parietal sites (Cp1) from 800 to 1200ms (t(26) = 2.31, p holm = 0.029, corrected, Cohen’s d = 0.44, 95% CI -2.40, −0.140]; Context Familiarity M = −2.69, SD = 3.46, SE = 0.66; Miss M =.-1.43, SD = 2.34, SE = 0.45) though not in the earlier latency of 200-400ms (t(26) = 0.443, p = 0.660; BF 01 = 4.37 indicating moderate evidence for the null). This demonstrated that the context familiarity condition was exhibiting substantively different physiology from recognition misses at centro-parietal sites during 800–1200 ms, refuting the null hypothesis that they were both reflecting the same implicit process outside of conscious awareness (e.g., guessing driven by implicit factors). Figure 10 Physiological effects of context familiarity versus recognition misses (A) Top: topographic maps of the difference map for activity of context familiarity minus activity for recognition misses ( N = 27). Maps are plotted for each time interval of 200–400 ms (ms), 400 to 600, 600 to 900 ms, and 800 to 1200 ms; color scale of topographic maps denotes amplitude differences from −2 to 2 mu-volts. Event-related potential (ERP) amplitudes (μV) for each condition plotted for representative sites of maximal activation (left frontal, F3, and centro-parietal Cp1), through an epoch of −200 to 1200 ms of a memory retrieval test. Shaded areas depict the standard error or the mean for each condition. (B) Replication data from Experiment 2. Data from three previously published studies ( N = 27). ERPs for each condition plotted for representative sites from original analysis (Cp1) and of maximal activation (right parietal Cp5, 200–400 ms), through an epoch of −200 to 1200 ms of a memory retrieval test. Section title: Experiment 1: Misses Educational score: 4.128267288208008 Domain: biomedical Document type: Study Language: en Since topography maps of Experiment 1 also indicated an early frontal activity pattern for this contrast, we conducted an exploratory analysis of the evident frontal region at its maximal left frontal site of F3. Inspection of these findings revealed that ERPs for context familiarity were more positive-going than misses in the early latency of 200-400ms (F3: t(26) = 2.55, p = 0.034 holm , corrected, Cohen’s d = 0.49, 95% CI [-2.07, −0.221]; cFam: M = 1.57, SD = 2.89, SE = 0.55; Miss: M = 0.427, SD = 3.01, SE = 0.57), continuing marginally 400–600 ms (t(26) = 1.90, p holm = 0.068, corrected, Cohen’s d = 0.37, 95% CI [-1.85, 0.07]; cFam: M = −4.36, SD = 3.62, SE = 0.697; Miss: M = −5.26, SD = 4.11, SE = 0.792) . Overall, these analyses revealed reliable, significant differences between conditions of context familiarity and implicit memory misses in Experiment 1 but were also assessed for the replicability in Experiment 2. Section title: Experiment 2: Misses Educational score: 4.181199073791504 Domain: biomedical Document type: Study Language: en The same pattern of differences between context familiarity and misses was also observed as being independently reproduced by targeted analyses in Experiment 2’s datasets ( N = 27) based upon directional hypotheses derived from the preceding findings for the same contrasts in Exp. 1, during the 800 to 1200 ms time interval of context familiarity effects, occurring at the same site as the primary results (Cp1: (t(26) = 1.79, p = 0.043, one-tailed, Cohen’s d = 0.34, 95% CI [0.046, ∞], cFam: M = 1.68, SD = 3.68, SE = 0.707; Miss: M = 2.68, SD = 3.35, SE = 0.644; maximal activation site of P4 (t(26) = 2.35, p = 0.013, one-tailed, Cohen’s d = 0.45, 95% CI [0.396, ∞], cFam: M = 0.689, SD = 3.33, SE = 0.64; Miss: M = 2.14, SD = 3.34, SE = 0.681) . Similar results to the primary findings in the earlier latencies of 200-400ms and 400–600 ms were also observed in Experiment 2’s datasets, revealing more positive ERP activity for context familiarity, albeit in more central-parietal sites of these participants (maximal at Cp5) (t(26) = 2.62, p = 0.007, one-tailed, Cohen’s d = 0.50, 95% CI [∞, −0.400], cFam: M = 1.93, SD = 2.71, SE = 0.52; Miss: M = 0.786, SD = 2.84, SE = 0.55; t(26) = 1.81, p = 0.041, one-tailed, Cohen’s d = 0.35, 95% CI [∞, −0.062], cFam: M = 0.019, SD = 3.08, SE = 0.594; Miss: M = −1.08, SD = 3.48, SE = 0.67, respectively). Section title: Experiment 2: Misses Educational score: 4.223335266113281 Domain: biomedical Document type: Study Language: en Together, these results from both experiments 1 and 2 revealed that neural activity for explicitly declared context familiarity judgments was reliably differentiated from that of implicit misses at the human scalp, during early latencies (200–400 ms) and later latencies , and across several different independent studies. This line of converging evidence refuted the null hypothesis that both conditions of context familiarity and implicit misses had the same functional significance or were representing the same cognitive process. 46 , 70 , 71 , 72 , 73 , 74 , 92 More broadly, recent work in the same experimental paradigm has also identified that other, more pure, kinds of implicit recognition processes can operate distinctly from misses, 18 but that pattern of implicit processing was entirely opposite of the negative-going central site patterns of ERPs characterized here for context familiarity, and thus not possible as a viable account of the present findings either. In sum, explicit context familiarity judgments were supposed to be equivalent to misses if representing similar implicit processing, but instead were significantly more positive than implicit misses in early epochs at frontal sites and then reversed to have significantly more negative voltage than at centro-parietal sites at later times in the epoch, thus providing clear evidence of divergent validity from the measures of implicit memory processing. This pattern for context familiarity cannot easily be attributable to accounts such as guessing or signals outside of episodic awareness and lending further weight against the possibility that context familiarity judgments were driven by implicit processes. Section title: General summary of findings Educational score: 4.1295881271362305 Domain: biomedical Document type: Study Language: en We began the investigation to understand how (by which process) people make accurate source judgments for items they recognize with low confidence. Emphasizing reproducibility in science 86 , 87 , 88 , 93 , 94 , 95 , 96 , 97 the current study first replicated the original behavioral performance and ERP effects of context familiarity as previously reported. 1 Extending those findings, the main finding here was that the effects of item familiarity, context familiarity, and recollection were reliably dissociable in multiple measures of both behavior and neural activity; these ERP effects were then reproduced in independent datasets. These patterns of effects cannot be accounted for by a priori predictions made by models of only a single- or dual processes of episodic memory without making post-hoc modifications. Item- and context-familiarity thus appear to be operating as fundamentally different kinds of memory processes, based upon established norms for identifying cognitive processes via neuroimaging and behavioral data, 42 , 46 , 71 , 72 , 73 , 74 , 98 , 99 , 100 , 101 , 102 such that dissociable physiological activity occurring at different times, at different locations, and for different conditions, cannot be taken as evidence that they are reflecting the same cognitive process and must therefore reflect at least partially non-overlapping cognitive operations. Together, this provides strong evidence that these three observations of ERP effects of memory are reflecting mutually exclusive, distinct episodic memory processes, and therefore advancing an updated model of the organization of episodic memory as discussed in further detail across each finding throughout the sections below. Section title: Behavioral findings Educational score: 4.16522216796875 Domain: biomedical Document type: Study Language: en Item familiarity and context familiarity were found to be behaviorally distinct in measures of response time, both in item judgments and in source judgments. Control analyses that held memory strength constant among conditions still preserved these differences and demonstrated that they were not confounded by recognition confidence levels. Item familiarity responses were faster during item judgments, whereas context familiarity responses were faster during source memory. It is difficult to account for these patterns of dissociations if attributing the responses to the same underlying cognitive processes of a single familiarity signal. 20 , 21 , 25 , 33 Context familiarity responses were also responded to significantly different than were responses of recollection, with recollection being faster than both item- and context-familiarity conditions during recognition and slower during source memory . There are two different ways that one can interpret these patterns of behavioral results: (1) They are consistent with existing findings of the relative speeds of recollection and familiarity (recollection being slower and familiarity being faster 21 , 55 ; (2) they are contrary to traditionally-held patterns of recollection being slower than familiarity. Each view will be discussed in more detail below, but importantly, regardless of interpretation, the memory conditions were reliably distinct in behavioral measures, indicating that mnemonic processing for context familiarity is distinct from item familiarity and recollection. Section title: Behavioral findings Educational score: 4.210428237915039 Domain: biomedical Document type: Study Language: en Traditionally, recollection has been conceptualized as a slower, deliberative process, whereas familiarity was modeled as a faster, automatic process. 21 As reviewed in the Introduction, source memory judgments are typically considered a general (though not exclusive) measure of recollection, which in the present study was reliably slower during source memory than the conditions of both context- and item-familiarity responses. Those results from source memory RTs are thus consistent with traditional characterizations of recollection as a slower, deliberative process. 21 Accordingly, item recognition tasks are usually considered to be a relatively better measure of familiarity-based responding, and faster response times observed here for item-familiarity than for context-familiarity in the present findings can thus be seen as it being the item (not the context) that is familiar during this early stage of the memory task. In this view, that recollection responses were also faster in item recognition would be seen merely that their inclusion of the highest confidence responses was driving a concurrent higher item familiarity and thus faster recognition time, consistent with traditional patterns. As the context familiarity responses then go on to become faster than item familiarity responses during the source judgments, it preserves the traditional notion that familiarity is also a faster automatic process-this time it is familiarity for context that is differentially faster (not items). That is, in a traditional view of RTs results are seen as showing that the two different types of familiarity (item, context) are faster than each other in each of the respective domains in which they are tested for representing differentially (item recognition, source memory), and ultimately consistent with the common findings that familiarity operates faster, while recollection is a slower process. Section title: Behavioral findings Educational score: 4.1027631759643555 Domain: biomedical Document type: Study Language: en Alternatively, the pattern of faster recollection during item recognition responses (and slower than context familiarity in the source judgments) could also be seen as departing from common findings that recollection is generally a slower process than item familiarity. While some studies have found that recollection can sometimes be faster than familiarity in some instances, 103 , 104 that discrepancy was suggested to likely be due to instructions to participants that they respond after both memory processes are complete, thereby delaying the responses times. 21 The current paradigm also requires subjects respond to a combination of both item and source memory confidence ratings on each trial, which could similarly impose complex demands on their memory judgements. Moreover, recent studies noted below have reported recollection to have faster responses than familiarity during recognition, suggesting that the traditionally assumed speeds of recollection and familiarity should not necessarily always be taken as simply one-directional (i.e., that familiarity must always be faster than recollection) and that is likely more complex in directionality. Section title: Behavioral findings Educational score: 4.153105735778809 Domain: biomedical Document type: Study Language: en For instance, a review of pupillometry studies of recognition memory concluded that, contrary to common observation of behavioral studies, recollection is not always the characteristic “slow and effortful” process typically assumed, but can also be quite “fast and easy” in its manifestation as a memory process. 105 When more advanced modeling methods were used for measuring the speeds of memory processes across six different experiments, recollection was again found to operate as both fast and slow, 106 similar to findings in the present data. Such patterns are also consistent with proposals that recollection is a two-stage process that includes both an initial rapid assessment of memory, plus a later second stage that is slower and more deliberative, 107 and with behavioral studies suggesting a third recognition process of familiarity. 108 Together, the response time profiles observed in the present work are consistent with other studies, 109 while also adding insight from specific memory response conditions that have not previously measured response times, to reveal that regardless of chosen interpretation views, the conditions remain nevertheless as neurocognitively distinct. Section title: Physiological findings Educational score: 4.212085723876953 Domain: biomedical Document type: Study Language: en In physiological measures, first, a triple dissociation of activity patterns was evident in general ERP effects observed during the basic memory measure of hits vs. correct rejections, qualified by a significant condition x time × location interaction that revealed a mid-central FN400 effect from 400 to 600 ms, a left parietal LPC Effect from 600 to 900 ms, and a BCN effect from 800 to 1200 ms, and replicated in a second independent dataset. Second, when investigating individual ERP effects of the specific memory conditions of item-familiarity and context-familiarity, each was found to be reliably different within-subjects and across subjects and was dissociated across the different latencies and locations on the scalp as noted above, and each was also dissociated from recollection. The same results were observed for each independent condition when contrasted against the standard ERP baseline condition of correct rejections; all of these findings were also reproduced in archival data from independent studies. This suggests that differential neurocognitive processes underlie each of the memory judgments, respectively. 46 , 71 , 72 , 73 , 74 , 102 Section title: Physiological findings Educational score: 4.122544288635254 Domain: biomedical Document type: Study Language: en The neural correlates for context familiarity did not exhibit the LPC nor the FN400 effects (the putative correlates of recollection and item-familiarity, respectively) in any analysis. The absence of such standard ERP effects was further bolstered by the Bayes factor results, which provided moderate evidence that both the LPC and FN400 were not present for these memory judgments instead of being merely undetectable. This conclusion is further bolstered by the finding that context familiarity exhibited significant effects present elsewhere in time and scalp location, so the absence of LPC and FN400 correlates could not be merely a case of insufficient statistical power to detect such differences. Section title: Why might context familiarity effects occur later than item familiarity? Educational score: 4.133731842041016 Domain: biomedical Document type: Study Language: en In our main ERP contrasts of each memory condition , context familiarity manifested effects later than item familiarity , and behavioral response times for context familiarity judgments were similarly later than those for item familiarity [although we note that during the source memory judgment context familiarity responses were faster than item familiarity ]. To a certain extent, the present work is not designed to directly answer why the times differ, but importantly is reporting the original finding that they are, in fact, different at all . One speculative reason is that context information may be broader than item information: encompassing additional elements/features that require neural pattern completion 110 , 111 , 112 , 113 , 114 - and that this could take the extra few hundred milliseconds that we observe here. We note here that the later ERP time interval was not the only time that context familiarity was found to exert an effect: it also differed reliably from item familiarity ERPs during the early epoch of 300–500 ms , too. We underscore that this early finding was important to the present work, because it demonstrated that the two memory conditions are occurring through differential patterns of neural activity early in the epoch (300–500 ms)- not just later. Section title: Why might context familiarity effects occur later than item familiarity? Educational score: 4.186113357543945 Domain: biomedical Document type: Study Language: en There should also be caution in over-interpreting the response time patterns of ERP effects earlier than the behavioral effects. The timings of ERP effects are occurring substantially before the later behavioral memory judgments, which might seem odd to researchers unfamiliar with ERP research on memory. However, this pattern of faster ERP times than behavioral times for the same memory processes has been generally true for most studies throughout the literature. This is because ERP effects have generally never been thought to represent a direct 1:1 mapping of memory process (as discussed in 22 ) but instead are widely regarded as “the putative neural correlates” of the memory processes. 47 That is, the ERPs are covert measures of memory-related activity, 80 but the overt memory behavior is generally thought to occur later in time (when people indicate their memory response) after the initial neural processing has set the stage for integrating the ensuing cognition and then deploying the actual motor response. So, there should be caution exerted in assuming too much about the timing of ERPs-what matters most, in our view here, is that they differ at all, and thus must be representing at least partially non-overlapping cognitive processing. 46 , 47 , 72 , 73 , 74 , 102 Section title: Possible alternative interpretations Educational score: 2.9916937351226807 Domain: biomedical Document type: Study Language: en How are study participants making accurate source memory retrieval for items recognized with low confidence? There are several different accounts which could potentially be used to interpret them for future explorations. We will address four possible alternatives and limitations here for what other accounts might explain the pattern of findings for context familiarity: (1) generic item familiarity, (2) delayed recollection, (3) the late parietal negativity (LPN) observed in other studies for controlled search processes, and (4) implicit memory or guessing. Each is reviewed below. Section title: A single signal of generic familiarity? Educational score: 4.180075168609619 Domain: biomedical Document type: Study Language: en One possibility to account for the present findings is that results for context familiarity could perhaps “simply” reflect a variant of generic familiarity-based processing for which item and context are merely differences in levels but not kinds, such as the distinction between absolute (pre-experimental) and relative familiarity (in-the-experiment) of the stimuli. 75 , 76 This potential account would propose that the ERP measures of each condition of item- and context-familiarity would vary incrementally rather than fundamentally, similar to how ERP measures have been found to vary incrementally to incremental gradations of item familiarity strength. 1 , 115 , 116 Yet, that pattern was not found in the present study, which instead revealed the two conditions to vary in fundamental, not incremental, ways. The present effects of context familiarity were significantly dissociable from the effects of item familiarity-in measures of both behavior and physiology, so cannot be the same. 46 , 47 , 71 , 72 , 73 , 74 Thus, a shared, single generic process of familiarity cannot account for this pattern of memory responses that have been observed here and in several independent datasets. Section title: A single signal of generic familiarity? Educational score: 4.177084922790527 Domain: biomedical Document type: Study Language: en The ERPs for conditions of item- and context-familiarity were found to significantly differ in N400 potentials from 300 to 500 ms, and the N400 component has also been known to be influenced by factors such as context. 92 , 117 , 118 , 119 , 120 , 121 , 122 This association with context is consistent with the present interpretations of the psychological constructs we describe as “context familiarity” and was differentiated from the opposing patterns observed for item-familiarity. The posterior distribution of the FN400 effect for the item-familiarity condition is consistent with other findings ascribing it to a sub-type of absolute familiarity (as opposed to relative familiarity, which is reported to have a more anterior scalp distribution. 76 , 92 , 123 , 124 The FN400 effect observed in the present study had the same mid-central topography as was reported originally for this paradigm, 1 which is between the frontal and posterior distributions observed in other studies that manipulated factors of relative and absolute familiarity, 75 , 76 , 119 , 120 , 121 , 123 , 124 respectively. This mid-central distribution may likely reflect a combination of both relative and absolute familiarity with the stimuli in this particular paradigm since the study was not designed to differentiate those factors. Section title: A single signal of generic familiarity? Educational score: 4.0138444900512695 Domain: biomedical Document type: Study Language: en Finally, accurate source memory has also been shown to be sometimes achieved through reliance on cognitive processes such as item familiarity 52 , 58 and unitization, 60 , 61 , 62 , 64 , 65 , 125 , 126 and the Source Monitoring Framework 55 , 56 has directly proposed that familiarity can support source judgments in some contexts. However, weighing against such possibilities of the source judgments being contributed to by those forms of unitized item-familiarity is that prior ERP findings for item familiarity and unitization contributing to source judgments are found as positive-going ERP difference effects, 52 , 76 , 125 instead of the significant negative-going ERP effects observed in the current data. Section title: Does the BCN reflect a delayed recollection process? Educational score: 4.05333137512207 Domain: biomedical Document type: Study Language: en Another possible account for the effects of the context familiarity condition is that perhaps recollection is a bit delayed and happening later in the epoch (Authors thank a previous Reviewer for suggesting this possibility). There are several broad reasons why it is likely that the ERP effects of the context familiarity condition could not plausibly be reflecting a “delayed recollection” process, which we will follow with several additional specific reasons. For instance, first there is scant evidence to support a contribution of recollection to the condition we measured as context familiarity: there has been no ERP evidence of the putative neural correlates of recollection for this condition across several different studies, and this absence of evidence has been quantified by Bayes Factor analyses providing consistent evidence of absence. Alternatively, the evidence that has accrued across various studies and measures continues to unambiguously indicate that the condition of context familiarity differs from recollection trials in substantive ways that include behavioral response times for both recognition and for source memory judgements, and several physiological measures across several experiments. Section title: Does the BCN reflect a delayed recollection process? Educational score: 4.181379318237305 Domain: biomedical Document type: Study Language: en The context familiarity condition also tends to be low confidence source judgments, which argues against the premise that a later process of slow recollection might be driving their trials following a delayed memory search. This is because if recollection occurred later then it could be assumed to have more high confidence correct source judgments (and yet the response data doesn’t have that profile). That is, if recollection is “delayed”, then the common features of recollection should also be evident in at least a reasonable proportion of those source memory response conditions for when that response is “eventually” happening, and those features of recollection commonly include high confidence responses for source memory. 20 , 21 , 34 , 35 , 54 , 115 , 127 , 128 , 129 Since that, too, runs contrary to the pattern of responses evident in the present data, it weighs against the theory of “delayed recollection”. This alternative account of delayed recollection would also de facto hold that a delayed recollection arrives later in time, even though the source judgments for this particular condition are provided faster than the source judgments in the actual recollection condition. As such, it is difficult for that to be reconciled in light of the pattern of behavioral responses. The “delayed recollection” account also would have trouble explaining why the context familiarity ERPs differed reliably from the item familiarity ERPs during the early latency of 300–500 ms if it was only representing a delayed process happening later after 1200 ms. For these reasons, it is improbable (and unsupported by evidence) to speculate that the effects of context familiarity could plausibly be reflecting a delayed recollection; however, more specific reasons to reject this theory also exist and are detailed below. Section title: Does the BCN reflect a delayed recollection process? Educational score: 4.1151957511901855 Domain: biomedical Document type: Study Language: en The term “delayed recollection” appears only sparsely in the memory literature. One of the few extant studies of “delayed recollection” using ERPs 130 found that “delayed recollection” occurred under conditions of “changed viewing conditions”, which were not a part of, nor directly applicable, to the present study. Notably, that study did not find any negative-going ERP effects to be associated with their condition of ‘delayed recollection’, which was instead associated with the traditional, positive LPC measures (the opposite of the present findings). Since recollection typically produces a specific hallmark pattern of positive ERP effects, 44 , 45 , 47 , 48 and we instead observed a distinct opposite polarity of negative-going ERP effects, the logic to support a “delayed recollection” account remains lacking. That is, there is not a reasonable explanation for why the polarity of the canonical recollection-related physiology would have been reversed among our other control analyses demonstrating the standard positive-polarity of recollection effects in all other standard conditions of memory. This provides an additional line of evidence against a “delayed recollection” account and it is thus difficult to support as a viable account of our present findings. Section title: Does the BCN reflect a delayed recollection process? Educational score: 4.1433892250061035 Domain: biomedical Document type: Study Language: en Another related ERP study 131 claiming “delayed recollection” did report a later negative-going difference for hits vs. correct rejections that they attributed as late parietal negativity (LPN, see section 5.4.3 below), but in their paradigm their reported LPN effect actually became more reduced in their “delayed memory condition”, and was instead larger in their condition of immediate memory retrieval. This, too, is the opposite of what would be predicted from a ‘delayed recollection’ account of the present findings, and thus it, too, ends up providing evidence against the “delayed recollection” account. Could the BCN effects we attribute to context familiarity instead be reflecting processes of non-criterial recollection 132 ? If that were so, one could predict that then there would still be an LPC associated with recollecting the non-criterial information-a pattern of results that we did not see in the present series of studies, and for which there was Bayes factor evidence of absence. Section title: Does the BCN reflect a delayed recollection process? Educational score: 3.9135828018188477 Domain: biomedical Document type: Study Language: en The alternative theory of “delayed recollection” is further complicated by other problematic aspects: it would predict no differences in ERPs between the condition we call context familiarity and that of correct rejections because if there was not memory/processing yet (i.e., it occurred via a ‘delayed recollection’) then there would be no reason for the condition to differ from a non-memory condition baseline of correct rejections. But that is not what was found in the data: there is in fact a significant difference between the condition of context familiarity and correct rejections, and we need to then know why or, at least, be able to offer a plausible account to explain why that difference exists. Our account provides at least one viable and parsimonious explanation (it is the dissociable memory process of context familiarity), whereas the delayed recollection account does not provide an explanation. Section title: Does the BCN reflect a delayed recollection process? Educational score: 4.325613021850586 Domain: biomedical Document type: Study Language: en The theory of delayed recollection is additionally difficult to sustain when one thinks about it more deeply to its natural consequent end. It is, in effect, saying that recollection might be present later in time if only we were to look (a potentially unfalsifiable hypothesis). One problem with that is that it is improperly assuming a direct 1:1 mapping of cognitive processes to ERP effects, de facto assuming that the timing of one effect (ERPs) must coincide with the timing of another effect (the cognitive process). However, it is widely understood that ERP effects of memory are considered to be covert measures that occur separate to the overt subjective experience of conscious memory reported by the subject. 18 , 47 , 72 , 73 , 80 , 133 Thus, it requires acknowledging that both item-familiarity and recollection are both normatively occurring in a delayed manner evident in their reported response times (in the present data: 2.4 s and 1.8 s, respectively) that is preceded in time by their respective ERP correlates (e.g., ∼400 msec and ∼800 msec, respectively). That is, all recollection is delayed, at least in the sense that the traditional recollection condition’s responses are normatively delayed from the earlier ERPs effect correlates that are well-established as the LPC. Why then would it now be something different and special for this one condition of accurately retrieving the source-especially when considering that the context-familiarity source memory responses are notably faster (e.g., happening less delayed) than both recollection and item-familiarity? The post-hoc modifications needed to support the delayed recollection account’s uniqueness to the context familiarity condition while leaving the canonical ERP effects of item-familiarity and recollection unaccounted for are thus deemed untenable. Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.202652931213379 Domain: biomedical Document type: Study Language: en Another common suggestion about the broad central negative (BCN) ERP effects in the present study is that they could represent the Late Parietal Negativity (LPN), (Authors thank two Reviewers for suggesting this possibility) which is a heterogeneous effect sometimes seen in studies of source memory and other tasks (for Reviews see 134 , 135 ). The LPN has been linked with a controlled search process for episodic memory and is coarsely thought to reflect the mental processes of re-constructing the prior episode. As a brief primer, the LPN was proposed to reflect a reconstructive or evaluative process in memory search when memory features are not fully recoverable. 134 , 135 , 136 Prior work studying the LPN has identified early and late variants of the LPN, with the earlier variant occurring approximately 600–1200 ms post stimulus onset and being variously interpreted as (1) a mnemonic search for context, 137 (2) re-activating context-specifying information from an encoded episode, 136 , 138 or (3) during later epochs that we did not measure , associated with the evaluation of fluency, 77 , 137 , 139 or (4) reflective of the absence of information . 140 Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 3.894583225250244 Domain: biomedical Document type: Study Language: en The results here may appear at first glance to be similar to the late parietal negativity (LPN), in that they are negative-going ERP differences that occur relatively late in the epoch, and extend to some parietal regions (though observed here and previously to emanate from foci in more central regions 1 ). As such, the present findings could potentially be seen to fit one/some of those four different accounts of the LPN’s functional significance. However, upon closer inspection there are several reasons, described fully below, of why the LPN interpretation does not fit the observed patterns in the present datasets. Thus, the LPN interpretation remains problematic and difficult to reconcile. Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.0896148681640625 Domain: biomedical Document type: Study Language: en First in determining if the present study’s BCN might instead be the same effect as the late parietal negativity (LPN) is a direct appeal to what the authors of the primary review of the LPN have said about the matter, 135 where it was specifically noted that the LPN was not the same effect: “ … in the studies by Addante et al. … these components are unlikely the same ERP component as the LPN.” (page 631), and “Addante et al. examined ERP correlates of source memory for items that were recognized low confidence … the rather broad scalp distribution and the early onset of the negativity do, however, not necessarily support an LPN interpretation of this effect ”. (page 634 135 ). The original report of the negative ERP effects of context familiarity 1 also similarly provided why the two were not the same effects, concluding that: “… these factors make it difficult to attribute the observed effects as an LPN ” (page 448). So, neither of the authors of either of the two effects thought they were measuring the same things, and this bears some weight toward a measured interpretation of the findings. Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.157577037811279 Domain: biomedical Document type: Study Language: en Another possible account of the present findings as an LPN effect is that they may reflect a “controlled search process” that is one of the core (albeit vague) functional significances ascribed to the LPN. 135 There are several lines of reasoning weighing against this possibility. In theory, every trial of the study should be inducing participants to engage a “controlled memory search” simply by virtue of the memory question being asked of them. That is, the participants are expected to be searching their memory on every trial for if they remember the item and the source of its encoding condition, then reporting it. In that sense, the controlled memory search would be a variable that is held constant across all conditions, thus canceling out in the contrasts, and leaving open the question of why this particular memory condition would show the negative ERP effect when compared to other conditions that also involve the searching of memory do not show the effect. Furthermore, if the present effect was representing a controlled search process, then it would have also presumably been seen in the recollection condition when compared to correct rejections, if participants searched memory for controlled recollection of the information. However, the same negative ERP effects weren’t seen in the recollection condition (which had far more trials included for statistical power, too), nor were the same effects seen for the item-familiarity condition in which participants were searching for the unknown source information as well, as described further below. Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.172578811645508 Domain: biomedical Document type: Study Language: en Expanding upon this line of reasoning, consider the item familiarity condition (i.e., successful recognition memory hits, but lacking source memory): participants report that they do not have source memory and spend significantly longer response times on the source memory judgments. If participants had made a correct item judgment on the basis of item familiarity, and could not recollect the source of the event, then presumably they would certainly be engaging in a controlled search process of their memory to see if they could find that source information. This provides a solid premise to infer that the condition would also include a “controlled search of memory” for the source information that still comes up empty for them, and makes a clear hypothesis that we should see a major negative-going ERP effect on these trials if it reflected the same thing as the LPN. 135 Yet, that is not what the present data shows, nor in several of the independent replications of the finding, and instead we see that the item familiarity condition differs reliably and consistently from the context familiarity condition, and that they each reliably differ from a baseline condition of correct rejections. Hence, the present differences must be attributable to another variable than just a controlled search of memory, and this creates a challenge for the LPN interpretation. Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.263138771057129 Domain: biomedical Document type: Study Language: en An additional point of differentiation of the present results from the LPN is the different patterns of topographic and temporal activities. Differences in topographical and temporal profiles of neural correlates of behavioral responses has been widely taken to reflect dissociable cognitive processes. 18 , 46 , 47 , 48 , 70 , 71 , 72 , 73 , 115 The LPN is generally found by other studies to be maximal in posterior parietal areas, whereas the current effect was observed in superior central regions of the scalp and distributed broadly to both frontal and central-parietal areas, and had been previously differentiated from posterior sites. 1 In regard to timing, the LPN has been previously characterized as beginning during periods after the epoch ended in the present study . 135 Among those irreconcilable factors was sensitivity to memory conditions: the LPN has been reported to either be invariant to source accuracy (i.e.,: it was present for both correct and incorrect conditions 137 ) or even to be larger for incorrect source judgments. 141 However, the current conditions’ effects have been found to be specific for correct source memory when compared directly to incorrect source memory. 1 Furthermore, other lines of evidence weighing against the LPN account of our findings comes from testing a direct prediction made that the LPN should be present “ not necessarily tied to successful memory retrieval but also observed during misses … ” (pg. 635 135 ). We did not find that prediction supported in the present data, as the present findings directly dissociated ERP effects of misses from the ERP correlates of context familiarity, which was also replicated, and thus adds to the considerable line of evidence weighing against an interpretation of the present findings for context familiarity as an LPN. Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.1817827224731445 Domain: biomedical Document type: Study Language: en A related problematic issue for an LPN account of the present findings is that the LPN is well-researched but poorly defined for its functional significance. The LPN is operationalized broadly as either a “reconstructing of the past” or a “controlled search process”, which, colloquially, only means “trying to remember”, which should occur on every memory retrieval trial to one extent or another and is difficult to reconcile with the present pattern of results. Due to the poor operational definitions available to the LPN, it is possible that the LPN findings from at least some other studies could instead be reflecting context familiarity. 138 , 142 That is, there is also the other possibility that some instances of reported results interpreted as an LPN might have actually been misinterpreted and reflecting the effects of context familiarity, instead of an LPN. In such cases, misinterpretation of effects could be due to lacking paradigmatic sensitivity (i.e.,: being able to dissociate influence of item familiarity from context familiarity, or recollection) or having lacking a theoretical framework to understand results as reflecting context familiarity (i.e.,: if one was only considering the existence of two episodic memory processes of recollection and generic familiarity). Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.122927188873291 Domain: biomedical Document type: Study Language: en For instance, another laboratory’s study of contextual memory retrieval confidence of source information, their findings of a broad, Cz-centric ERP negativity at approximately 1000 ms occurring for source memory retrieval were interpreted as an LPN in that study 138 but their results’ characteristics could also be interpreted as reflecting context familiarity instead, given the successful retrieval of the context of source memory attributes in that study. Leynes et al. 142 also report BCN effects occurring from 500 to 800 ms post-stimulus in their Experiments 2 and 3 for recognition hits being more negative than correct rejections for the conditions of testing context in a masked word priming study, which could be seen context familiarity influencing mnemonic processing, much as was reported in an ERP study of cued recall with semantic primes. 85 Section title: Is the BCN a case of the late parietal negativity (LPN)? Educational score: 4.075519561767578 Domain: biomedical Document type: Study Language: en In sum, the main, non-specific feature shared among the present findings and the LPN is that each is a negative-going ERP effect, but that in itself is not a very helpful descriptor, just as many other positive-ERP effects are not assumed to reflect the same thing just by virtue of their being a positive difference. The present findings are clear that the BCN observed in the present studies is evident to the specific condition of context familiarity and not reasonably ascribed to other negative-going ERP effects such as the LPN, nor cognitive operations associated with the LPN such as a controlled search process or reconstruction of the past, concurring with the prior observations of their differentiation, 1 , 135 respectively. Section title: Are BCN effects driven by fluency or guessing? Educational score: 3.990586519241333 Domain: biomedical Document type: Study Language: en It is also possible that the current results might reflect a form of guessing. In this view, effects may be reflecting conceptual implicit memory contributions to source memory, as has been seen in the form of guessing observed in prior studies of item recognition. 89 However, ERP findings of guesses indicated that guess processing was occurring much earlier in time (200–400 ms and 600–700 ms) than what we found in the current study , 89 so the current findings do not bear those hallmarks of guessing. The fact that two explicit declarative responses (item, source) were observed for judgments in the condition is also inconsistent with guessing, too, as is the above-chance performance of the responses. While it is possible people could have been successfully guessing in these item + source judgments, this possibility becomes increasingly less likely when considering that participants were given the option of saying they “don’t know” the source in our task’s paradigm , and which are thus excluded from the condition. Section title: Are BCN effects driven by fluency or guessing? Educational score: 4.176915168762207 Domain: biomedical Document type: Study Language: en Furthermore, if results were influenced by guesses, then it is notable that the purportedly accurate “guesses” would actually be driven by an implicit memory process (i.e., “recognition without awareness”). We conducted several direct analyses to assess if context familiarity ERP activity resembled the known hallmark signs of other implicit processing (i.e., misses) that would have been presumably supporting the guess behavior, but instead found that it was significantly different in both time and scalp location from implicit misses. That finding is further bolstered by another, different implicit activity recently observed in the same dataset for a purer form of implicit memory (IMAP) 18 that was found instead to manifest in right parietal regions in positive-going ERP effects from approximately 400 to 1000 ms . Prior work discussing the requirements for a condition being ‘recognition without awareness has established the criteria that information about context should be absent from the memory 143 – which also rules out the condition of interest for context familiarity in the present study. Taken together, the evidence weighs against interpretations of context familiarity being primarily the result of processes associated with guessing from underlying implicit memory signals. Section title: Are the negative ERP effects reflecting implicit fluency? Educational score: 4.054128646850586 Domain: biomedical Document type: Study Language: en It is probable that, much like many explicit memory processes, context familiarity is also supported by forms of implicit processes (i.e., repetition priming, perceptual priming, contextual fluency) that then give rise to the explicit memory judgments, as has been found in other studies of item familiarity and cued recall. 85 , 144 , 145 Familiarity of context may naturally represent various forms of fluency in processing information which has linked negative-going ERP effects for old items to repetition and perceptual fluency. 52 , 90 , 91 , 120 , 146 As such, it is possible that these explicit response trials for context familiarity could be supported by an underlying fluency heuristic that leads one to accurate recognition and source judgments. Section title: Are the negative ERP effects reflecting implicit fluency? Educational score: 4.2704548835754395 Domain: biomedical Document type: Study Language: en According to this explanation, the negative ERP effect likely reflects the fluency heuristic. This effect might purportedly be obscured during high-confidence trials by the predominance of positive LPC effects associated with recollection that could override the presumed baseline negative ERP activity postulated to occur in recollection conditions as well. While such an explanation is hypothetically conceivable in this familiar context, where various possibilities exist, it remains speculative and lacks parsimony with the data. This is because it fails to explain why conditions of item familiarity did not display similar negative ERPs in the apparent absence of recollection. Additionally, the effects of context familiarity manifest later in time than the very early latencies (200–400 ms) where fluency is often found exerting its effects. 76 , 91 Through the series of systematic analyses here we demonstrate that there are still core distinctions between the kinds of familiarity represented by items and context, both of which surely are multiply determined by earlier sensory and contributory processes. We believe that based upon the combination of converging data and the divergent findings for studies measuring fluency at much earlier latencies, locations, and conditions, the present findings cannot be explained by mere fluency. Section title: Future directions Educational score: 4.098118782043457 Domain: biomedical Document type: Study Language: en There are several next steps which can be envisioned for future research based upon the present findings. For instance, intracranial measures of subsections of the medial temporal lobe regions such as the parahippocampal cortex and perirhinal cortex 147 , 148 , 149 , 150 , 151 , 152 , 153 , 154 , 155 , 156 offer clear hypothesis-driven tests of model predictions from the present work . Such kinds of studies can include both invasive and non-invasive stimulation approaches to both enhance 157 , 158 , 159 , 160 , 161 , 162 , 163 , 164 , 165 , 166 , 167 and disrupt 157 memory operations of different episodic processes, and assessing their relevance in real-world environments/context. 168 , 169 , 170 , 171 Other potential future approaches include exploring for neuropsychological dissociations among various types of MTL patients 172 or those with specified focal lesions of MTL subregions, 22 , 78 , 173 or electrophysiological searching for differential oscillatory bandwidths that may possibly be selective for each process. 19 , 147 , 148 , 149 , 150 , 162 , 174 , 175 , 176 , 177 , 178 , 179 , 180 , 181 , 182 , 183 , 184 , 185 , 186 , 187 , 188 , 189 , 190 , 191 Section title: Future directions Educational score: 3.9877188205718994 Domain: biomedical Document type: Study Language: en In pursuing future studies, note that the specialized condition used in the present study to measure context familiarity (low-confidence recognition hits accompanied with accurate source memory) does not necessarily mean that it is the only potential way to measure context familiarity (i.e., the present study also found the ERP effects using general ‘old-new' recogntion contrasts, and in general source memory contrasts used in prior studies 22 ). Rather, it is likely just one of many possible approaches to capturing an elusive cognitive process. The findings here suggest the importance of including multiple measures of memory into experimental protocols, as it permitted the leverage needed to identify the combined conditions needed to measure context familiarity in the present experiments. We would expect future studies to find context familiarity to accordingly be measurable in other ways pending properly sensitive experimental designs that do not conflate it with recollection or item-familiarity or guessing. Section title: Future directions Educational score: 4.129304885864258 Domain: biomedical Document type: Study Language: en For example, we surmise that context familiarity could be found in future studies using different paradigms that systematically vary repetition of context while holding items constant and vice versa, similar to repetition paradigms used in prior fMRI studies 2 , 38 , 40 , 69 , 192 that found results similar to the present data. Our measure here was a combination of multiple responses (memory confidence scales) across multiple measures (item and source memory judgments), and thus reflects the sophisticated paradigmatic sensitivity that will likely be needed for follow-up explorations. Toward this end, studies should use an unequal confidence scale for source memory judgments to permit a “source unknown” response in order to avoid the guesses that are inherently integrated in balanced confidence scales 89 , 193 , 194 , 195 ; so, researchers should be sure to move from a commonly used 6-point confidence scale 38 to a 5-point confidence scale. 1 , 18 , 19 , 67 That is, including a “source unknown” option into source memory tests should be essential for future researchers to avoid contaminating source memory responses with instances of guessing or the source unknown. Section title: Future directions Educational score: 4.09633731842041 Domain: biomedical Document type: Study Language: en Another direction for future studies could be to assess the possibility of delayed recollection supporting the condition identified here as context familiarity. One way to do that could be by studying response locked analyses of ERP or oscillatory analyses, 175 , 176 , 177 , 178 , 179 , 196 as opposed to the stimulus-locked events studied here for the purposes of consistency to the literature of known ERP effects of episodic memory. 44 , 45 , 47 , 48 , 59 , 71 , 85 But it is important to also note that such studies of response-locked activity in this paradigm risk being confounded or conflated in their baseline period due to the preceding activity of the item recognition prompt/decision in in the present paradigm, so future studies would need to be very carefully designed to ensure those and other factors are properly disambiguated similar to as has been done in fMRI studies. 197 Section title: Implications for models of memory Educational score: 4.762869834899902 Domain: biomedical Document type: Study Language: en The medial temporal lobe region of the parahippocampus has been modeled by several frameworks to be a neural substrate supporting contextual representations of episodic memory 6 , 16 , 17 , 198 , 199 .This is based upon neuroimaging studies identifying activations of that region for contextual processing, 38 , 40 , 41 while ascribing item familiarity to the adjacent perirhinal cortex. 40 , 69 , 192 , 200 This has been paralleled by findings from studies using intracranial recordings showing temporal dissociations of familiarity and recollection processing amid the parahippocampal gyrus and hippocampus, respectively, 109 , 152 , 153 , 201 , 202 which has been similarly observed using functional neuroimaging methods. 151 Figure 11 Physiologically informed model of long-term memory processes Top, (A) The tri-component model presents an updated representation of the canonical declarative memory framework that is inclusive of physiological findings from physiological data indicating that recollection and familiarity are distinct processes of episodic memory, 22 , 46 and that context- and item-familiarity are also dissociable processes in episodic memory . Model depicts the emerging views that differential forms of implicit fluency contribute to driving explicit familiarity. 76 A sample schematic of recollection shown models it as a threshold process based upon physiological findings in the current and former data indicating that is limited to high-confidence responses and does not extend to low-confidence responses even if source memory is retrieved. 1 , 35 , 53 Context familiarity and item familiarity are each depicted as continuous processes of signal detection, with representative distributions of old and new information each. Bottom, (B) Anatomical and conceptual representation of medial temporal lobe processing of mnemonic information, based upon the “binding-items-in-context (BIC)” model, 6 , 16 updated here to include differential familiarity processes for items and context in the perirhinal and parahippocampal cortices, respectively. Note that the model presents a simplified representation of the breadth of complex memory operations and neuroanatomical substrates. Section title: Implications for models of memory Educational score: 4.380746841430664 Domain: biomedical Document type: Study Language: en Neuropsychologically, converging reports of the perirhinal cortex role in item familiarity come from a rare clinical patient, NB, with an epileptic resection lesion specific to the perirhinal cortex that left the parahippocampal cortex intact. 203 This patient was deficient in familiarity for items (words) but showed intact abilities of familiarity for pictures and faces, 173 , 204 , 205 , 206 which we consider here as broadly representing kinds of context in episodic events and this could be seen as performance consistent with the patient’s intact parahippocampus service of context familiarity (though it is possible that faces and/or picture stimuli might have potentially instead be treated by that patient as an item in certain studies with other contexts, or alternatively the face/picture memory performance might have potentially been supported by the other hemisphere’s intact perirhinal cortex). Similar reports of familiarity for contexts in the absence of object familiarity or recollection have emerged from neuropsychological 207 and normative studies using visual scenes of mazes, whereby it is the spatial layout of the scene that is experienced as familiarity and not the items or objects. 9 , 10 , 208 Section title: Implications for models of memory Educational score: 4.203143119812012 Domain: biomedical Document type: Study Language: en Together with the present studies, these findings converge to suggest an updated framework for the organization of long-term episodic memory from the canonical declarative memory model used ubiquitously throughout textbooks, 209 , 210 , 211 , 212 , 213 , 214 , 215 , 216 , 217 , 218 , 219 , 220 , 221 , 222 , 223 following from the BIC model that had originally motivated the hypotheses tested in the present work. 16 We propose an updated model to conceptualize the organization of specific episodic memory processes among a broader framework of long term memory , which is primarily based upon being specifically physiologically informed, whereas most prior models of long term memory have instead been either informed primarily by cognitive psychology, neuropsychology, or neuroanatomical/neuroimaging studies 6 , 15 , 16 , 30 , 31 , 210 , 224 , 225 , 226 , 227 (though see 76 for an example of a physiologically informed model of just familiarity-specific memory processing). Section title: Implications for models of memory Educational score: 4.186126232147217 Domain: biomedical Document type: Study Language: en Our new tri-component model provides an updated representation of the canonical declarative memory framework and BIC model, that is now inclusive of findings from physiological data indicating that recollection and familiarity are distinct processes of episodic memory, 1 , 22 , 46 , 47 and that context- and item-familiarity are also dissociable processes in episodic memory . This physiologically-informed model also encompasses the emerging views that differential forms of implicit fluency contribute to explicitly aware familiarity 76 , 90 , 119 , 120 , 121 , 124 , 146 , 228 and that other forms of implicit memory depend upon the hippocampus. 18 , 78 , 229 , 230 , 231 , 232 , 233 , 234 , 235 Section title: Implications for models of memory Educational score: 4.272397041320801 Domain: biomedical Document type: Study Language: en In our proposed framework , the episodic process of recollection is modeled as a threshold process based upon physiological findings in the current and former data, since the LPC effects were found to be limited to high-confidence responses and did not extend to low-confidence responses even if source memory is retrieved 1 ; for other related cognitive frameworks see. 34 , 53 , 58 Context familiarity and item familiarity are each depicted as distinct continuous processes of signal detection for relatively old and new information distributions, 1 , 115 , 116 , 236 based upon the current and prior data, and as opposed to the traditional model of them both merged within a single continuous process of general familiarity. The model also updates the understanding of the parahippocampal and perirhinal cortices as processing differential familiarity signals , as opposed to previous models depicting them to operate amid a single familiarity signal along both regions of the larger parahippocampal gyrus. 6 , 15 , 16 , 25 , 26 , 199 Section title: Implications for models of memory Educational score: 4.0011796951293945 Domain: biomedical Document type: Study Language: en How might the subjective experience of context familiarity occur during cognition? We draw upon our proposed additions to the BIC model/variants 6 , 15 , 16 to suggest a cognitive framework that can be built to understand how the condition of context familiarity may arise or manifest (note: this is a proposal of how it might occur in some instances but should not be taken as suggesting that it is how recognition works in every case, which has inherent variability). This account both echoes and extends models provided by prior work investigating the role of context in episodic memory, 1 , 17 , 27 , 192 while integrating fluency heuristics. 76 , 90 , 120 It has been proposed that people use a fluency heuristic to make recognition judgments, 76 , 90 and the current findings extend that by suggesting the possibility that a fluency heuristic can also be used to support accurate source memory judgments, too. This would be based upon an underlying fluency for context, as opposed to fluency for items or conceptual/perceptual dimensions. Section title: Implications for models of memory Educational score: 4.130068302154541 Domain: biomedical Document type: Study Language: en By our account, as a retrieval probe is first shown on a screen by itself, the item does not at first seem familiar (i.e., no FN400 for item familiarity from ∼300 to 600ms that we observed). The context, however, may seem familiar, even if they do not recollect the details of either the item or how the context was bound with other details from the prior episode. Akin to how item familiarity can be derived from underlying fluency of the stimuli, so too would context familiarity be facilitated by a separate underlying fluency for the context. If the context does not initially seem familiar from ∼300 to 600 ms, then in the ensuing time (600–900 ms, LPC) the participant would continuing to mentally look back in time for any context in which to place the item being shown on the screen (e.g., ‘where might I have seen that before?’), seeking the pattern completion process to autocomplete a recollection of the relevant details from the prior event. During that time (600–900 ms), that autocompletion process of binding any existing neural signals of context together with the presented item fails (i.e., our observations of an absence of evidence for the LPC correlate of recollection), consistent with the slower response times observed for these item judgments. Section title: Implications for models of memory Educational score: 4.155864715576172 Domain: biomedical Document type: Study Language: en As time continues the person continues to assess their memory for any connections of details, something about the stimuli remains diagnostic for prior exposure (the BCN effect emerges to reliably differentiate from correct rejections and item familiarity), which could be either the explicit familiarity of a contextual detail such as the encoding source or the implicit sense of its contextual fluency for associated information about the item. The successful retrieval of some familiar contextual information would be enough to logically deduce that the item must have been old. 4 , 5 That is, one can then draw upon that awareness that the context seems familiar to derive the logical inference that the item is likely old, akin to how other studies have found item familiarity can lead to false alarms in associative recognition by similar logical deductions. 12 , 197 , 237 , 238 , 239 Ultimately, this basis of a retrieved prior context is sufficient to support an accurate hit in item recognition, albeit with low confidence because the item itself is not remembered directly, while the correct source is identified in the ensuing judgment based upon that retrieved familiarity of the context of its prior exposure. 5 The item is thus accurately recognized due to the context seeming familiar: context familiarity. Section title: Implications for models of memory Educational score: 4.120537757873535 Domain: biomedical Document type: Study Language: en Importantly, our tri-component account provides an improved precision in characterizing human episodic memory, and as such could help to better understand disparate findings from memory studies and neuropsychological patient impairments that occasionally arise in the literature. That is, if prior studies had been conflating distinct familiarity processes for items and context, and conflating context familiarity with instances of recollection, when occurring in differential proportions and under differential experimental conditions, it could easily produce disparate clinical findings that have been reported about source memory, context, recollection, and neuropsychological impairments thereof. 6 , 15 , 20 , 22 , 29 , 31 , 172 , 173 , 205 , 206 , 227 , 240 , 241 , 242 , 243 If we are now able to delineate between these three distinct but overlapping processes of memory, it could help illuminate a better understanding of the nature of memory impairments and lead to better precision in types of amnesia diagnoses. Section title: Implications for models of memory Educational score: 2.6417667865753174 Domain: other Document type: Study Language: en The idea that there can be different kinds of familiarity for items and for contexts has been previously mentioned by several others. 1 , 4 , 17 , 66 But, whereas prior work established the premise that there can be separable familiarity of items and familiarity of contexts, 4 , 17 they nevertheless proposed that each was stemming from the same singular memory process of underlying familiarity. For instance, the Discrepancy Attribution Hypothesis offered that people can produce either piece of mnemonic information separately, 4 stating: Section title: Implications for models of memory Educational score: 1.291548252105713 Domain: other Document type: Other Language: en “ contextual information can also cause the person to experience a feeling of familiarity: encountering a stimulus in a context that is unusual for that stimulus ( e.g., a clerk on the bus) can cause this .” However, and importantly, they go on to propose that “ the use of contextual information to perform judgments about the past is not qualitatively different from the use of identity [emphasis added]” (page 561). 4 Section title: Implications for models of memory Educational score: 3.3179314136505127 Domain: biomedical Document type: Study Language: en Here, we put forth a fundamentally different view: that production of familiar context does differ qualitatively from the production of familiar item information and provide converging lines of support that the familiarity of items and familiarity of contexts are evidently operating as separable independent neurocognitive processes. Section title: Implications for models of memory Educational score: 4.316851615905762 Domain: biomedical Document type: Study Language: en In conclusion, the field of memory research is replete with complexities in memory behaviors in normative and clinical patient populations that are difficult for existing theories to fully account for. We show here that the common measure of source memory can be supported by a disparate process that is independent of both recollection and item-familiarity. The memory condition of context familiarity was found to be distinct from item familiarity, in addition to previously identified dissociations from recollection. This conclusion was evident from triple dissociations observed in both behavioral and physiological measures. Moreover, the differences in item-familiarity and context familiarity reflected differential neural processing at both the individual subject level as well as trial-wise differences in memory processing that was identified within-subjects and were replicated across several independent studies. These findings cannot be accounted for by relying upon using only two processes of episodic memory for interpreting the results. 36 , 54 Item familiarity and context familiarity are therefore seen as fundamentally different kinds of familiarity processes independently operating in service of episodic recognition 46 , 70 , 71 , 72 , 73 , 74 : one process for items and another for context, and each distinct from recollection. This extends traditional dual process models of recognition to reflect that context familiarity constitutes a third process of episodic memory. Section title: Limitations of the study Educational score: 4.111792087554932 Domain: biomedical Document type: Study Language: en ERP studies are inherently limited in spatial resolution of their topographic distribution of effects and are generally unable to provide source localization of the subdural cortical and subcortical source generators of the effects recorded at the scalp. 80 , 196 , 244 Therefore, spatial distribution of the physiological effects reported here should be expected to have a reasonable amount of variability in future studies, and may vary upon different experimental factors, protocols, stimuli, and paradigms. While the physiological effects of the present study’s main Experiment 1 18 , 67 were found to be reproducible in independent datasets collected from different demographics in different universities (Experiment 2), 1 , 19 , 22 , 78 Experiment 2’s archival datasets were unable to collect meaningful response times to memory judgments due to a protocol that asked participants to withhold their response until after viewing the memory probe for 1.5 s, thus rendering the response time uninformative and unable to asses for reproducibility of the results from Experiment 1. Therefore, while the physiological effects that formed the backbone of the present study were independently replicated, the behavioral results remain to be assessed for the extent of their potential replication among future studies of larger samples. Section title: Lead contact Educational score: 1.0156084299087524 Domain: other Document type: Other Language: en Requests for further information and resources should be directed to and will be fulfilled by the lead contact, Richard J. Addante, PhD. Raddante@fit.edu . Section title: Materials availability Educational score: 0.9819539189338684 Domain: other Document type: Other Language: en Any additional materials not listed can be made available upon request to the lead contact . Section title: Data and code availability Educational score: 1.211004614830017 Domain: biomedical Document type: Other Language: en • Data: This paper analyzes existing, publicly available data, accessible via the previously published study using the same data, 18 freely available under the terms of the GNU General Public License at https://github.com/IMAP-Lab/IMAP-Lab-IMAP-Implicit-Memory-Automated-Pipeline . • Code: This paper does not report original code. • All Other Items: All materials and code used to generate and run the present experiment is available as a downloadable zip folder at https://github.com/IMAP-Lab/IMAP-Lab-IMAP-Implicit-Memory-Automated-Pipeline/blob/main/ItemSourceMemoryERP_Experiment_In_Presentation_AddanteLab.zip . Peer reviews and author responses from several rounds of reviews are available on Biorxiv at https://www.biorxiv.org/content/10.1101/2024.07.15.603640v5.supplementary-material . Section title: Acknowledgments Educational score: 0.9980204701423645 Domain: other Document type: Other Language: en Funding support of this work came from the 10.13039/100000002 National Institutes of Health (NIH), which included grants 2 L30 NS112849-03 , 2 L30 NS112849-02 , and 1 L30 NS112849-01 awarded to R.J.A. from the 10.13039/100000065 National Institute of Neurological Disorders and Stroke (NINDS), from 10.13039/100013185 Florida Institute of Technology (FIT) grants to R.J.A. from the Institutional Research Incentive (IRI) program. Authors thank the Florida Tech Provost Office of Dr. Marco Carvalho for generously providing direct funds to support the project. D.L.D. received support from grants R01 NS124585 from the NIH/NINDS and A1321808 from Medtronic, Inc. J.P.C. and R.J.A. received support from a NASA/FL Space Consortium Grant. Authors thank Alana Muller, Lindsey Sirianni, Anderson Wilder, and Cristo Rey for research assistance, and are grateful for the constructive contributions of six anonymous and one non-anonymous reviewers. Publication of this article as Open Access was funded by the Open Access Subvention Fund and the John H. Evans Library at Florida Institute of Technology and the Office of the Vice Provost for Research. Section title: Author contributions Educational score: 0.8859380483627319 Domain: other Document type: Other Language: en R.J.A. designed the study, supervised the data collection, analyzed the data, created the figures, interpreted the findings, wrote the manuscript, and responded to reviews. E.C. and J.P.C. contributed to data analysis. R.W., J.B., and D.L.D. contributed to interpretation of findings and manuscript preparation. Section title: Declaration of interests Educational score: 0.9791291356086731 Domain: other Document type: Other Language: en Authors disclose that they have no competing interests. Section title: Key resources table Educational score: 1.6125023365020752 Domain: biomedical Document type: Other Language: en REAGENT or RESOURCE SOURCE IDENTIFIER Deposited data Pre-processed and analyzed data, experimental materials for conducting the experiment. Addante et al., 2023 18 https://github.com/IMAP-Lab/IMAP-Lab-IMAP-Implicit-Memory-Automated-Pipeline Peer reviews and author responses from several rounds of reviews. Biorxiv , the preprint server of biology https://www.biorxiv.org/content/10.1101/2024.07.15.603640v5.supplementary-material Software and algorithms ERPLab Toolbox, Software Lopez-Calderon & Luck 237 www.erpinfo.org EEGLab Toolbox, Software Delorme & Makeig 197 https://sccn.ucsd.edu/eeglab/index.php MATLAB, Software MathWorks https://www.mathworks.com/products/matlab.html Infomax ICA Bell & Sejnowski, 238 N/A Section title: Experiment 1 Educational score: 4.085999488830566 Domain: biomedical Document type: Study Language: en The current study (Experiment 1) consisted of a re-analysis of previously published ERP data, 18 , 67 so the sample size was determined by the number of participants’ data that was available in the archival dataset; the study was not pre-registered. The participants consisted of 61 right-handed students free from neurological disorder and memory problems. Data was not used for four participants due to noncompliance issues (i.e., pressed only one button throughout the task or ignored experimenter’s instructions), data lost due to experimenter error (N = 1) or EEG data deemed unusable (N = 2) due to excess motion artifacts/noise that resulted in an exclusion of the majority of EEG trials. This presented a working data set of N = 54 for the current study, which was more than double the size of the original study reporting physiological correlates of context familiarity (N = 25), 1 and triple the sample size standards of many of the foundational ERP studies of recognition memory. 42 , 46 , 102 , 115 , 245 , 246 , 247 , 248 , 249 Section title: Experiment 1 Educational score: 3.9240291118621826 Domain: biomedical Document type: Study Language: en As described by the data’s original publication 67 : Participants were recruited through a combination of methods including advertisements placed around CSUSB or through the schoolwide research pool SONA. Participants recruited through advertisements were paid $10 an hour for sessions that lasted approximately 2 h. The majority of participants were women ( N = 48); 57% were Hispanic, 23% Caucasian, 11% Asian, and 10% identified as more than one ethnicity. The average age was 23.5 years old ( SD = 4.82). Findings do not apply to only one particular sex, gender, or demographic; the study was a secondary analysis of archival data, 1 , 18 , 19 , 22 , 67 and thus was constructed to be neutral in consideration of any particular sex or gender or other demographic factor. Inclusion of participants was based upon the nature of the archival data that was available (we included all datasets available), which had included anyone who volunteered to participate for the research from broad advertisement efforts on the campus of California State University – San Bernardino, and determined based upon self-reporting. Since the pursuit of the present study was one that sought to assess the reproducibility of prior findings, analyses were performed agnostic to sex and gender or other demographic factor in order to faithfully reproduce prior findings of that had adopted the same approach. There are no known reasons for why an absence of demographic-specific analyses would limit the study’s generalization, and the findings were observed to be reproducible across several independent studies that comprised different demographic proportions and produced results in line with traditional findings of ERP effects of memory in the field across many labs, countries, and demographic distributions since the early 1990s. None of the participants reported any visual, medical, or physical issues that would interfere with the experiment. Most participants spoke English as their first language ( N = 47) and those who had indicated speaking a different first-language had been speaking English for an average of 16.73 years ( SD = 4.74, SE = 1.22, Median = 17.0, Minimum = 7, Maximum = 25). Section title: Informed consent statement Educational score: 1.0587390661239624 Domain: biomedical Document type: Other Language: en Written informed consent was obtained for original participation in the experiment and protocol approved via the Institutional Review Board of California State University – San Bernardino, 67 and data analyses observed the privacy rights of human subjects, consistent with the Declaration of Helsinki. The current investigation of secondary re-analysis of the previously published datasets was approved by the Institutional Review Board of Florida Institute of Technology (IRB Approval number 23–131). Section title: Experiment 2 Educational score: 4.031135082244873 Domain: biomedical Document type: Study Language: en The participants included in Experiment 2 were aggregated across three previously published studies 1 , 19 , 22 , 78 that used nearly identical experimental protocols of item recognition confidence followed by source memory judgments as were used in the present Experiment 1, 18 for a total sample of N = 56. These studies had only directly contrasted conditions of recollection and context familiarity, but had never directly assessed if the ERPs for item- and context-familiarity differed. 66 Each study’s cohort of participants have been previously reported for having intact levels of familiarity-based recognition on both behavioral and electrophysiological measures that did not significantly differ as a function of younger/middle aged adults. 22 , 66 , 78 They have therefore been previously treated as equivalent cohorts of familiarity-based recognition, which was the subject of the present investigation, 22 , 78 and thus we also treated them accordingly here as well. Section title: Experiment 2 Educational score: 3.8755009174346924 Domain: biomedical Document type: Study Language: en The participants were reported in prior studies 1 as consisting of twenty-five healthy right-handed undergraduate students (Mean age = 20.4 years [SD = 2.9, SE = 0.60, Min = 18, Max = 30], mean education level = 14.4 years [SD = 1.8, SE = 0.4, Min = 12, Max = 19] demographics of 52% Caucasian, 20% Hispanic, 20% Asian, 8% more than once race; seventeen female) and twenty-two 1 , 19 right-handed undergraduate students (Mean age = 20.9 years [SD = 3.1, SE = 0.70, Min = 18, Max = 29], Mean education 14.5 years [SD = 1.4, SE = 0.30, Min = 13, Max = 17], demographics of 55% Caucasian, 9% Hispanic, 5% African American, 32% Asian; ten females), all recruited from the University of California–Davis Psychology Department subject pool. They received credit for participation and were free from neurological, visual, motor, or other medical disorders. An additional nine middle-aged participants (six female; Mean = 45.4 years, SD = 12.5, SE = 4.2, Min = 27, Max = 57) were included whom were tested on the same memory protocol (six male) 22 , 78 and had a comparable profile of education (M = 16.8 years, SD = 5.7, SE = 1.9, Min = 12, Max = 31) and majority demographics (78% Caucasian, 22% more than once race). Section title: Informed consent statement Educational score: 1.0822923183441162 Domain: biomedical Document type: Other Language: en The experiments had been previously conducted and published as approved by the University of California–Davis Institutional Review Board protocol for research on human subjects. 1 , 19 , 22 , 66 The current investigation of secondary re-analysis of the previously published datasets was approved by the Institutional Review Board of Florida Institute of Technology (IRB Approval number 23–131). Section title: Method details Educational score: 3.9520187377929688 Domain: biomedical Document type: Study Language: en The paradigm used was the same item- and source-memory confidence paradigm that has been routinely used in our prior reports to characterize various facets of memory, 1 , 18 , 19 , 22 , 67 , 78 , 166 with slight modifications as noted below. 67 This paradigm consisted of an encoding phase containing four sequential study sessions during which participants studied 54 words per session, followed by a retrieval phase that contained six test sessions in which the participant’s memory was tested for 54 words in each session. Item recognition was tested on a five-point confidence scale with ‘1’ indicating being sure the item was new, and ‘5’ indicating being sure the item was ‘old’ . Section title: Method details Educational score: 4.080763816833496 Domain: biomedical Document type: Study Language: en During the encoding phase, participants were given instructions to make a simple decision about the word presented. The participants were either asked to judge if the item was man-made or if the item was alive. The instructions were presented in one of two counterbalanced orders: ABBA or BAAB. The participants viewed four lists of 54 words during the encoding phase. After the encoding phase was complete, the EEG cap was applied to the scalp of participants. During the memory test, participants viewed a total of 324 words, 216 of which were presented in the encoding phase and 108 of which were unstudied items (new items). All words presented during study and test were presented in white font on black background screen. Word stimuli were selected from the same source as stimuli used in the original study in 2012 and preserved the same characteristics. Word stimuli were selected from the Medical Research Council Psycholinguistics Database ( http://www.psych.rl.ac.uk/MRC Psych Db.html). Word stimuli were all nouns, had an average rating of concreteness of 589 (min = 400, max = 670), imageability of 580 (min = 424, max = 667), Kucera–Francis Frequency of 30 (min = 3, max = 198), and an average number of 4.9 letters in each word (min = 3, max = 8). Section title: Method details Educational score: 3.9772682189941406 Domain: biomedical Document type: Study Language: en During the memory retrieval phase, the participants were read instructions asking them to judge if the stimulus word presented was old (studied during the encoding phase) or new (not studied before in the encoding phase) . To begin a trial, a screen with a small white cross at the center was presented for one of three randomly chosen times: 1 s, 2.5 s, or 3 s. Then the participants were presented with a word in the middle of the screen, the numbers 1, 2, 3, 4, and 5 evenly spaced beneath the word, the word “New” on the left by the number 1, and the word “Old” on the right under the number 5. Participants pressed any number between 1 and 5 to indicate if they confidently believed the word was old (5), believe the word was old but was not confident (4), did not know if the word was old or new (3), believe the word was new but was not confident (2), or confidently believed the word was new (1). This prompt was subject-paced, and participants were told to choose the response that gave the most accurate reflection of their memory, and to respond as quickly and accurately as possible. Section title: Method details Educational score: 3.889779806137085 Domain: biomedical Document type: Study Language: en Immediately after each decision on item memory confidence, participants were asked to answer a source memory question about if the word came from the animacy decision task or the man-made decision task. The word and numbers remained on the screen but this time, word “Alive” was presented on the left by the number 1, and the word “Manmade” was presented on the right under the number 5. Participants were told to choose the response that gave us the most accurate reflection of their memory and could respond that they confidently believed the word was from the animacy task (1), believe the word was from the animacy task but was not confident (2), did not know the source of the word or had replied in the question directly before that the word was new (3), believe the word was from the manmade task but was not confident (4), or confidently believed the word was from the manmade task (5). Trials were terminated by subject response. Each session consisted of a list of 54 words. Six lists of 54 words were presented during the retrieval phase. The retrieval phase of the paradigm also included a simple metacognitive question to participants for estimating their performance, which occurred once every ten trials and for which the data has been previously reported elsewhere for metacognition effects. 67 The current investigation focused instead upon the memory related responses, as the metacognitive response data has been reported previously. Each session consisted of a list of 54 words; overall, six lists of 54 words were presented during the retrieval phase. Section title: Conditions of interest Educational score: 4.1168293952941895 Domain: biomedical Document type: Study Language: en Following common convention in the field, we operationalized these processes based on the combination of responses given for item recognition confidence and source-memory judgments, consistent with the way prior research has defined these conditions. For recollection, we followed the convention of prior findings that it represented instances of retrieving high-confidence item recognition followed by correct source information: item responses of ‘5’ accompanied by source judgments that were correct ( Figure 1 . 1 , 22 , 67 ; For context familiarity, we followed the same approach used to originally identify this process 1 : instances of low-confidence item recognition accompanied by correct source judgments . Item familiarity was defined based upon previous work 18 , 19 as instances in which participants retrieved successful item recognition (hits, combining 4 and 5 responses) but reported having no source memory information (source unknown, 3 responses) . These conditions of item- and context-familiarity are ones which have never been directly compared against each other in the literature while using behavioral or ERP measures, and so it remains to be determined if and how they may differ, and the extent to which the process of familiarity may be organized among these variables as a continuous or distinct process(es). Section title: Conditions of interest Educational score: 3.2547805309295654 Domain: biomedical Document type: Study Language: en Response times for item recognition and source memory responses were measured as follows: item recognition times were measured from the onset of the memory probe (i.e., the word) to the button press of the recognition decision; source memory response time was measured from the onset of the source memory prompt (which happened immediately upon the end of the item recognition judgment) to the button press of the source memory decision. Section title: Electrophysiological acquisition Educational score: 4.1812663078308105 Domain: biomedical Document type: Study Language: en Each subject was tested individually inside a private chamber. Stimulus presentation and behavioral response monitoring were controlled using Presentation software on a Windows PC. EEG was recorded using the actiCHamp EEG Recording System with a 32-channel electrode cap conforming to the standard International 10–20 System of electrode locations and was acquired at a rate of 1024 Hz. The EEG cap was sized while the participant’s face was wiped free of skin oil and/or makeup in preparation for attaching ocular electrodes. Five ocular electrodes were applied to the face to record electrooculogram (EOG): two above and below the left eye in line with the pupil to record electrical activity from vertical eye movements, two on each temple to record electrical activity from horizontal eye movements, and one electrode in the middle of the forehead in line horizontally with the electrode above the left eye as the ground electrode. EOG was monitored in the horizontal and vertical directions, and this data was used to eliminate trials contaminated by blinks, eye-movements, or other related artifacts. The EEG cap was placed on the participant’s head and prepared for electrical recording. Gel was applied to each cap site and impedances were lowered below 15 KOhms via gentle abrasion to allow the electrodes to obtain a clear electrical signal. Subjects were instructed to minimize jaw and muscle tension, eye movements, and blinking. Section title: Electrophysiological analysis Educational score: 4.22285795211792 Domain: biomedical Document type: Study Language: en Physiological measurements of brain activity were recorded using EEG equipment from Brain Vision LLC. All EEG data was processed using the EEGLAB and ERPLAB toolboxes in MATLAB. 250 , 251 The EEG data was first re-referenced to the average of the mastoid electrodes, passed through a high-pass filter at 0.1 Hz as a linear de-trend of drift components, and then down sampled to 256 Hz (Hz). The EEG data was epoched from 200 ms prior to the onset of the item recognition stimulus to 1200 ms after the stimulus was presented. 67 Independent components analysis (ICA) was performed using Infomax techniques in EEGLab 252 for artifact correction and the resulting data was individually inspected for artifacts, rejecting trials for eye blinks and other aberrant electrode activity. During ERP averaging, trials exceeding ERP amplitudes of +/− 250 mV were excluded, as described in the previous report of this data. 18 , 67 A 30 Hz low pass filter was applied to each subject’s ERPs as a non-causal, infinite impulse response (IIR, Butterworth) filter, implemented through ERPLAB toolbox. 251 In order to maintain sufficient signal-to-noise ratio (SNR), all pairwise comparisons relied upon including only those subjects who met a pre-determined criterion of having a minimum number of 12 artifact-free ERP trials per condition being contrasted. 79 , 85 , 253 , 254 , 255 As was noted in the Introduction, the present work is not claiming any specifically process-pure ERP measurements of memory, but instead we adopt what others 44 , 47 , 48 , 59 as well as our own previously published positions 1 , 18 , 22 , 49 , 67 , 78 , 85 described as the ‘putative neural correlates’ of recognition memory processes. Section title: Measuring source memory performance Educational score: 4.061354637145996 Domain: biomedical Document type: Study Language: en The current study’s interest focused specifically upon combinations of item + source memory responses described below. Like most studies of source memory, we wanted to know how accurate people were in discriminating between the two sources of information in the experiment, and so excluded the source unknown responses from the performance calculation of source discrimination. This procedure collapses high- and low-confidence source judgments into general ‘correct’ and ‘incorrect’ conditions. We thus calculated this source memory performance in the same way as had been done in prior studies 1 : the total number of source correct trials divided by the total number of all correct & incorrect source memory judgments (excluding the source unknown responses) [ # correct source trials/(sum of # of correct + # of incorrect source trials)]. The source memory calculation we used is akin to the standard recognition measure of memory performance (%Hits-%FA) but applied to source memory discrimination, which would require excluding the 'source unknown' responses, since a false alarm in source memory would be a source misattribution (not the lack of source memory). When source memory discriminations occur between available options of the two sources for participants to choose from, they have a 50% chance or being right/wrong (source correct or source incorrect responses), thus chance levels are at 50% in that analysis (as opposed to 33% if assessing it relative to the three response options of correct, incorrect and unknown; see discussion below for further considerations of the limitations of such alternative calculation methods (Authors acknowledge a previous Reviewer for suggesting consideration of this alternative approach)). Section title: Measuring source memory performance Educational score: 3.9622209072113037 Domain: biomedical Document type: Study Language: en In excluding the ‘source unknown’ responses from the calculation of performance on source memory discrimination, it excludes the trials of when people had an absence of source memory. 194 , 195 This approach was taken because we did not want to know how frequently people remembered correct source information at all (i.e.,: out of all of the possible times that they could have), because this number would be artificially low, but rather how well they discriminated sources that they did remember. For example, consider a scenario in which people were tested on if episodic memory for where we learned various items of information in our lives. Then consider if the performance measures for memory measured the few times that we did remember correctly amid all the times when we couldn’t remember any source at all (likely most of the time, for naturalistic settings). Most people would [falsely] appear to be dense amnesiacs unable to retrieve source information above chance-despite likely having reasonable source discrimination capabilities for the times that they could retrieve source memory information. The same is true for clinical applications of the same principle: consider cases studying reality monitoring of auditory hallucinations in schizophrenia patients, whereby the pertinent question is about understanding how well the source determination is made when a source of the information is available to the patient-not the other instances in which it isn’t. Section title: Measuring source memory performance Educational score: 4.063910484313965 Domain: biomedical Document type: Study Language: en Our approach to measuring source memory performance is a common one that is sensibly used in other source memory studies. 60 For example, our standard approach used to measure source memory performance is not just the same as we have published with previously 1 but is also the same approach used by additional other studies measuring source memory performance, 256 where they note that: “ Conditional source measures control for overall differences in recognition by calculating the probability that the correct source is identified given that the item was correctly identified as old (p|source| = source hits/source hits + source misattributions)” . For these reasons noted above, we utilized the present method of calculation for source memory discrimination that excluded the ‘source unknown’ responses, as it provides the most appropriate treatment of participant’s memory while minimizing the extent of possible confounds. This approach also avoided the potential confounds of not knowing what response criterion a subject is adopting when making the ‘unknown’ response for source memory, as no two participants could be presumed to use the same such criterion. Importantly, it also ensured that the pursuit of replication could be achieved by using the same measures as were used in the preceding work we sought to assess for reproducibility. 87 , 88 Section title: Statistics Educational score: 2.553644895553589 Domain: biomedical Document type: Study Language: en Statistical details of experiments can be found as directly reported in-text of the Results, as well as in the Method details below. Following convention recommended in the field, statistics reports (i.e.,: ∗, ∗∗, ∗∗∗ etc.) are not included in figures, 257 but are described in full detail in the text of the manuscript’s results. “ N” denotes the sample size of the number of human participants, whereas “n” is used to denote the sample size of valid ERP trials used per participant in ERP analyses. Section title: Statistics Educational score: 4.126101016998291 Domain: biomedical Document type: Study Language: en Our hypotheses focused upon identifying three different processes of episodic memory: recollection, item familiarity, and context familiarity. We hypothesized that recollection would exhibit both an FN400 for item-familiarity and an LPC for recollection but would not exhibit a late broad central negativity (BCN) effect, whereas context familiarity would exhibit only an BCN and neither an FN400 or LPC, and that item-familiarity would be associated with only an FN400 effect but not an LPC nor BCN effect. As the current investigation was based upon clear a priori-defined hypotheses derived from prior findings, 1 analyses utilized planned paired t-tests to assess differences between the targeted conditions (two-tailed unless indicated otherwise) with an alpha level of 0.05. In cases where exploratory analyses were conducted to explore unplanned comparisons, ANOVA was used to qualify potential differences that may exist and were corrected with Geisser-Greenhouse corrections when necessary. Analyses conducted to assess the extent to which prior results could be found to replicate in independent datasets and/or were principally based upon a priori predictions that effects would differ in one way (i.e.,: context familiarity exhibiting more negative-going ERP amplitudes than correct rejections, item-familiarity 1 ); such analyses thus applied targeted directional hypotheses utilizing one-tailed t-tests where noted in order to maintain a properly principled statistical approach, though most were also still significant with non-directional two-tailed tests as well (i.e.,: multiply the p value by 2). Section title: Statistics Educational score: 4.054743766784668 Domain: biomedical Document type: Study Language: en In reporting results of behavioral response times, we followed convention in the field to report the mean values of reaction times. When outlier data points were removed from the mean values ( N = 2, using criteria of exceeding 3 standard deviations from the mean) the results from the analysis of mean response times remained the same. In this case, the two outlier subjects had longer mean RT values, merely indicating that some subjects sometimes responded a few seconds slower on uncertain memory conditions, which is common knowledge of reasonable variability in cognitive capabilities during conditions of uncertainty. Also, these inclusive data points are the aggregate of multiple responses for a person instead of a singular outlying value that might otherwise be considered as potential artifacts. Removing outliers based upon their post-hoc values would thus be inappropriately biasing the data based upon post hoc visual inspection of it. Therefore, we report mean reaction times with outlier data points included, since they represent the real average response times of subjects. Section title: Statistics Educational score: 4.169395446777344 Domain: biomedical Document type: Study Language: en Because a non-significant p -value in conventional frequentist t-test methods is unable to inform whether there is actually evidence for the null hypothesis or if there is merely not sufficient evidence for any conclusion at all, analyses that revealed a null finding were subsequently quantified using Bayes Factor (BF) analysis. Bayes Factor analysis is a tool that allows researchers to quantify the relative strength of evidence for the null hypothesis (invariance). 258 , 259 , 260 , 261 , 262 , 263 , 264 , 265 , 266 , 267 , 268 A resulting Bayes Factor value can generally be considered as the ratio of how likely a hypothesis is as compared to the likelihood to another hypothesis (for specific details see 262 , 265 ). For interpreting Bayes Factor result values, it is conventionally viewed that a Bayes Factor (BF 01 , evidence for the null hypothesis) of 0–1 typically represents there being no evidence available for the null hypothesis, 1–3 typically represents anecdotal evidence for the null hypothesis, a BF of 3–10 represents relatively moderate evidence for the null hypothesis, and a BF of 10–30 represents relatively strong evidence for the null hypothesis. 262 , 263 , 268 Thus, Bayes Factor results are reported as such for the pertinent analyses as representing the relative strength of evidence for the null finding as noted above (BF 01 ). The Bayes Factor analyses were computed for paired or one-sample t-test designs. Results were calculated using the standard scale of r = 0.707 and the resulting outputs are provided as values in favor of the null hypothesis using the recommended Jeffrey-Zellner-Siow Prior (JZS, Cauchy distribution on effect size). 265 Section title: Reproducibility Educational score: 4.079698085784912 Domain: biomedical Document type: Study Language: en The reproducibility of the effects of context familiarity was assessed in several ways through the present investigation. First, the present investigation (Experiment 1) was an assessment of the extent to which previously-reported effects 1 , 19 , 22 of context familiarity originally differentiated from the neural correlates of recollection in a sample of N = 25 could be found to be reproducible amid a larger sample ( N = 54) that had been previously published in the domain of memory metacognition. 18 , 67 Those original effects replicated in entirety in the present data. The sample of data of the present study thus demonstrated sensitivity of effect sizes and statistical power to detect the ERP effects of context familiarity originally discovered by the original study 1 by virtue of it having reproduced those findings of differences between context familiarity and recollection in a sample ( N = 54) 67 that was more than double the original sample size ( N = 25). 1 Section title: Reproducibility Educational score: 4.042593002319336 Domain: biomedical Document type: Study Language: en Second, when the present findings (Experiment 1) then discovered that the neural correlates of context familiarity were dissociable from those for item familiarity, we sought to assess the extent to which these findings would have been observed in the original study 1 if those authors had only thought to look (they hadn’t). These effects of the present investigation were also found to be replicated in entirety (Experiment 2), both within-subjects and between-subjects, and across the same control analyses. Third, we also sought the extent of reproducibility of the findings across a range of several control analyses conducted in both Experiments 1 and 2, which systematically varied different conditions to assess potential confounds and possible alternative accounts. The control analyses found that the results remained reproducible even when reducing signal to noise ratio of trials and when reducing statistical power limited to only low levels of familiarity strength (excluding trials of strong familiarity responses). Section title: Reproducibility Educational score: 4.0557355880737305 Domain: biomedical Document type: Study Language: en Fourth, as the present study was a secondary analysis of existing independent datasets that had already been published with sufficient power and sample size to detect differences in previously published papers, 1 , 18 , 22 , 67 it was not possible nor necessary 269 , 270 , 271 , 272 , 273 to perform an a priori power analyses for the present investigation since the sample size was already immutably established before the present work’s secondary investigation of analyses began. Similarly, widespread agreement in the literature that post-hoc power analyses would be both inappropriate and uninformative 269 , 271 , 272 precluded their use here. The present results were fully replicated in independent data, and in twice the sample size of previously published results that the present investigation also replicated; thus, the sufficiency for statistical power in the study is self-evident. | Review | other | en | 0.999999 |
PMC11699258 | Section title: Introduction Educational score: 4.021902084350586 Domain: biomedical Document type: Review Language: en Dental implant therapy is a popular method for replacing missing teeth; however, it can lead to technical and biological complications known as peri-implant diseases. 1 These biofilm-induced inflammations affect soft and hard bone tissues around osseointegrated implants. There are two categories of peri-implant diseases: peri-implant mucositis and peri-implantitis. 2 Peri-implant mucositis is a reversible inflammation of the mucosa around the implant, 3 while peri-implantitis involves progressive bone loss. 4 The prevalence of peri-implant mucositis ranges from 23.9% to 88%, and peri-implantitis varies from 8.9% to 45%. 5 , 6 Although plaque accumulation is the main cause, 7 other risk factors include smoking, history of periodontitis, lack of regular periodontal maintenance, diabetes, implant design or surface characteristics, and excess cement. 8 , 9 Section title: Introduction Educational score: 3.866135597229004 Domain: biomedical Document type: Review Language: en The standard approach for treating peri-implant mucositis is non-surgical treatment, which involves reinforcing oral hygiene practices, including professional and patient-administered plaque control techniques to mechanically remove microbial plaques from the implant surfaces. Studies have investigated adjunctive or alternative methods and non-surgical mechanical debridement for treating peri-implant mucositis. 10 These methods include antimicrobial photodynamic therapy, antiseptics, topical or systemic antibiotics, abrasive devices, laser therapy, home care mouthwashes, and probiotics. 11 - 14 However, it should be emphasized that regardless of the treatment used, adequate plaque control is important for the complete resolution of the condition. 15 Section title: Introduction Educational score: 4.104601860046387 Domain: biomedical Document type: Review Language: en Statins, commonly prescribed for lower lipid levels to prevent cardiovascular events, have shown potential for treating periodontal diseases. Studies have demonstrated that statins can reduce tooth mobility, tooth loss, and bone resorption in patients with chronic periodontitis. In addition to their lipid-lowering effects, statins possess anti-inflammatory, immunomodulatory, antioxidant, antithrombotic, and endothelium-stabilizing properties. They can also promote angiogenesis and stimulate bone formation. 16 , 17 Recent studies have shown that patients receiving statin treatment for chronic periodontitis have fewer pathological periodontal pockets than those not receiving such medication. Atorvastatin (ATV), in particular, demonstrates inhibitory effects on inflammatory cells and matrix metalloproteinases that play a crucial role in degrading connective tissue in periodontal diseases. 16 Section title: Introduction Educational score: 4.067668437957764 Domain: biomedical Document type: Study Language: en Akram et al. 18 found that 1.2% ATV gel applied locally improved clinical and radiographic parameters significantly. ATV was more effective than other statins, such as simvastatin, pravastatin, lovastatin, and fluvastatin, in lowering low-density lipoprotein. According to this study, ATV may be more effective than simvastatin in promoting bone regeneration in periodontal defects, reducing probing depth (PD) and clinical attachment level (CAL), and exerting anti-inflammatory effects. 17 , 19 Although none of the recent studies demonstrated the effectiveness of ATV gel once it is used locally to treat peri-implant mucositis, the present study was undertaken to evaluate the effectivity of 1.2% ATV gel in addition to mechanical debridement for the treatment of peri-implant mucositis. This study was necessary as statins are very effective in anti-inflammatory effects, and a limited number of studies have been conducted in this field. Section title: Study design Educational score: 3.898977756500244 Domain: clinical Document type: Other Language: en In this double-blinded randomized controlled clinical trial, 49 patients (20 males and 29 females, aged 40–60 years) diagnosed with peri-implant mucositis were selected from patients referred to a private periodontal office and the Faculty of Dentistry, Tabriz University of Medical Sciences. The patients were blinded to the type of treatment they received randomly (ATV or placebo gel), and the examiner was unaware of the patients’ allocation to the test or control groups. The researcher was aware of the interventions administered. Section title: Study design Educational score: 1.7385144233703613 Domain: biomedical Document type: Other Language: en The study protocol was initially approved by the Institutional Ethics Committee of the Islamic Azad University of Medical Sciences Tabriz Branch and was conducted in compliance with the Helsinki Declaration of 1975, as revised in 2013. The study findings were reported according to the 2010 CONSORT guidelines. Section title: Study design Educational score: 1.34842050075531 Domain: biomedical Document type: Other Language: en The study was officially registered with the local World Health Organization Registry Network under the code IRCT20220510054805N1. Following ethical approval, all the individuals were duly informed verbally, and written informed consent was obtained for their participation in the study. Section title: Patient grouping Educational score: 4.101408004760742 Domain: biomedical Document type: Study Language: en Forty-nine patients were selected based on the selection criteria, and after enrollment by an examiner, the patients were randomly allocated to either the test or control group. The randomization method was simple randomization and conducted using the RandomIZE Randomization tool app. The sample size was estimated to compare the average of the two groups from the respective formula with 95% confidence and 80% power, and an effect size equivalent to that of a similar study by Pradeep et al 21 equaled 21 participants in each group. Owing to the existence of three stages of follow-up and the possibility of dropping samples by 30%, the final sample size increased to 27 people in each group and 54 in total. Throughout all analyses of the research findings, the investigators were not part of or aware of the randomization process. Section title: Patient grouping Educational score: 3.9865715503692627 Domain: biomedical Document type: Study Language: en After mechanical debridement in both groups, 1.2% ATV gel (1.2 mg/0.1 mL) was injected into the pockets around the implant in the test (ATV) group and placebo gel in the control (placebo) group. Mechanical debridement was performed using a plastic curette at the baseline for each patient. Prepared 1.2% ATV gel (1.2 mg/0.1 mL) or placebo gel was injected into the pockets around the implant using an insulin syringe in the test and placebo groups . Cyanoacrylate tissue adhesive was used to protect the area. After treatment completion, the patients were not prescribed antibiotics or anti-inflammatory drugs. They were given specific instructions for a week, including refraining from chewing hard or sticky food, brushing near the treated areas, and using any interdental aid. At one and three months after the intervention, all clinical parameters were measured again in both groups in the same area. Section title: Clinical evaluation Educational score: 3.9985480308532715 Domain: biomedical Document type: Study Language: en The evaluation involved recording various clinical parameters such as BOP, PD, CAL, and pain on probing (POP) at different time points: baseline (before mechanical debridement), 1 month, and 3 months. A custom-made acrylic stent and a color-coded periodontal probe (UNC-15, Hu-Friedy, Chicago, IL, USA) were used to ensure uniformity in measuring these parameters. An examiner blinded to each individual’s treatment recorded all the pre- and post-treatment clinical parameters. Section title: Formulation of 1.2% ATV gel Educational score: 4.155946731567383 Domain: biomedical Document type: Study Language: en ATV gel was prepared by a pharmacist using standard methods described in pharmacology texts. 22 - 24 After intensive in vitro investigations for optimization and stability to prepare a multiple-dose solution of isotone and sterile ATV, the gel base was first prepared with sodium carboxymethyl cellulose (2.6%) and mannitol (9%), and the pharmaceutical stock solution was prepared at a concentration of 2% in propylene glycol solvent. Subsequently, at a 4:1 ratio, the drug solution was slowly added to the gel base. If opaque, 0.5% polysorbate 80 was added to the solution to increase the solubility of the drug. Finally, 1% benzyl alcohol was added to the solution as a preservative for injectable products. All steps were performed under laminar hood and aseptic conditions. The obtained solution was stored in sterile 1.5 mL of polyethylene microtubes and was stable at 2-8 °C for up to 1 month . Section title: Primary and secondary outcomes Educational score: 2.8281986713409424 Domain: biomedical Document type: Study Language: en The primary outcome of this study was the BOP. The secondary outcomes included PD, CAL, and POP. Section title: Statistical analysis Educational score: 3.4683167934417725 Domain: biomedical Document type: Study Language: en SPSS 22 was used for the data analysis. Descriptive statistics (frequency, frequency percentage, mean, and standard deviation) and inferential statistics (chi-squared test, Fisher’s exact test, and independent t test) were used for data analysis. An independent t test was used to compare the results between the two groups, and a paired t test was used to compare intragroup results. Statistical significance was set at P < 0.05. Section title: Descriptive results Educational score: 2.596276044845581 Domain: biomedical Document type: Study Language: en Forty-nine participants (one site/patient) out of 54 successfully concluded the study. Unfortunately, 5 individuals (2 in the ATV group and 3 in the placebo group) could not participate in the follow-up sessions . Thus, only 49 patients (20 men and 29 women) aged 41–60 years were included in the data analyses after completing the 3-month follow-up. Section title: Inter-group results Educational score: 4.1484551429748535 Domain: biomedical Document type: Study Language: en The clinical parameters (BOP, PD, CAL, and POP frequency distributions) at both the baseline and follow-up visits are shown in Tables 1 and 2 . After one month, the independent t test showed no significant difference ( P > 0.05) in the BOP index between the control and test groups. However, it significantly decreased ( P < 0.001) in the test group after three months. There was no significant difference ( P > 0.05) in PD between the two groups after three months, but it was significant one month after the intervention ( P < 0.001). The CAL and POP variables showed significant differences 1 and 3 months after the intervention ( P < 0.001). Section title: Intra-group results Educational score: 4.1308183670043945 Domain: biomedical Document type: Study Language: en A comparison of intra-group results using a paired t-test showed a significant difference in PD one and three months after the intervention ( P < 0.001). No significant difference ( P > 0.05) was found in CAL in the control group at baseline and one and three months after the intervention. However, within the test group, the difference was statistically significant ( P < 0.001). A comparison of the BOP results showed a significant difference ( P < 0.001) one and three months after the intervention. The POP results were significantly different ( P ≤ 0.05) one month after the intervention, both within the control and test groups. There was no significant difference ( P > 0.05) in the control group three months after the intervention, but the difference was significant ( P < 0.05) in the test group ( Table 3 ). Section title: Discussion Educational score: 4.0663347244262695 Domain: biomedical Document type: Review Language: en Statins have antimicrobial activity against periodontal pathogens and exhibit anti-inflammatory and immunomodulatory effects. 25 Animal and clinical studies have supported the idea that statins can be used as an adjunctive treatment to scaling and root planing (SRP) to manage periodontal disease, including chronic periodontitis. 18 , 26 Numerous studies have investigated the effectiveness of statins on various clinical parameters of periodontitis. 27 Due to the pleiotropic (cholesterol-independent) effects of statins, such as immunomodulatory and anti-inflammatory effects, they are expected to improve periodontal clinical outcomes. 28 Several studies have reported positive clinical effects, such as reduced PD, CAL, and BOP, with local administration of statins. Therefore, statins are considered a valuable adjunct to non-surgical and surgical treatments for periodontal disease. 18 , 26 , 27 Section title: Discussion Educational score: 4.072890758514404 Domain: biomedical Document type: Study Language: en The current study evaluated the clinical efficacy of 1.2% ATV gel as a supplement to mechanical debridement in treating peri-implant mucositis. Compared with the placebo gel, the results revealed a significant improvement in clinical parameters. To the best of our knowledge, no study has directly compared the use of 1.2% ATV gel in treating peri-implant mucositis. Section title: Discussion Educational score: 4.0124359130859375 Domain: biomedical Document type: Study Language: en In contrast, Saxlin et al 29 investigated the dual effects of statins on the periodontium. Their study revealed that statin use was associated with a higher risk of deep periodontal pockets in individuals without BOP. However, Kumari et al 30 discovered that using a local 1.2% ATV gel significantly improved clinical and radiographic parameters compared with a placebo gel. Similar results were also reported by Lindy et al, 31 who found that ATV or simvastatin led to 37% fewer pathological periodontal pockets than in the control group. In addition, animal models have suggested that statins have a beneficial impact on ligature-induced alveolar bone loss. 32 In the current study, BOP significantly decreased from baseline to three months, indicating that ATV may have anti-inflammatory properties. Section title: Discussion Educational score: 4.0347771644592285 Domain: biomedical Document type: Study Language: en In the current study, no significant difference ( P > 0.05) was observed in the BOP index between the control and test groups at the one-month follow-up. However, after three months, the difference was significant ( P < 0.001) in the test group. However, the results for the PD variable one month after the intervention were significant ( P < 0.001). There was a significant difference in CAL and POP between the control and test groups one and three months after the intervention ( P < 0.001). Section title: Discussion Educational score: 3.9498369693756104 Domain: biomedical Document type: Review Language: en Studies using local statins have reported significant improvements in clinical periodontal outcomes compared with those using SRP. The subgingival release of statins allows for high concentrations and low doses of drugs in the periodontal tissues, leading to high patient acceptance and the ability to control the long-term release of therapeutic agents at the target sites without causing systemic side effects. 33 Compared with oral administration, which results in rapid absorption and entry of the drug into the circulation, local application of the drug is preferred. 34 , 35 Therefore, it is safer to administer the drug locally, and clinical results have demonstrated that it improves chronic periodontitis. 27 Section title: Discussion Educational score: 4.001789569854736 Domain: biomedical Document type: Study Language: en Bertl et al 26 found that the type of statin used was associated with periodontal outcomes. One study showed that rosuvastatin was the most effective, whereas another reported statistically significant effects of ATV. In two clinical trials evaluating the application of statins as an adjunct to SRP, rosuvastatin produced the best results regarding clinical and radiographic parameters such as PD reduction, CAL gain, and radiographic defect fill. 27 The superior clinical advantages of rosuvastatin over ATV may be attributed to its stronger anti-inflammatory effect, which results in a greater reduction in C-reactive protein levels. 36 , 37 Section title: Discussion Educational score: 3.9461987018585205 Domain: biomedical Document type: Study Language: en Simvastatin is the most commonly used statin in clinical trials and is administered locally at a concentration of 1.2%. Numerous studies have shown significant improvements in clinical and radiographic results when using simvastatin. 27 Retrospective studies have also shown that patients with severe chronic periodontitis who were treated with simvastatin or ATV had lower PD indices than those who did not receive statins. 38 In addition, a recent study by Fajardo et al 39 indicated that ATV may reduce alveolar bone loss and tooth mobility in individuals with periodontal disease. Goes et al 40 reported that ATV could prevent alveolar bone loss in rats with ligature-induced periodontitis. Section title: Discussion Educational score: 4.059395790100098 Domain: biomedical Document type: Study Language: en Pradeep et al 21 evaluated the use of 1.2% ATV gel as a supplement to SRP for treating suprabony defects in patients with chronic periodontitis. The ATV group showed a significant reduction in clinical parameters such as BOP, PD, and CAL at the 3-, 6-, and 9-month follow-ups compared to the placebo group, indicating the anti-inflammatory effect of ATV. Section title: Discussion Educational score: 2.4709365367889404 Domain: biomedical Document type: Other Language: en It is recommended that more samples be used in clinical studies and that longer follow-up periods and investigations of inflammatory biomarkers be conducted. Section title: Conclusion Educational score: 4.039506912231445 Domain: biomedical Document type: Study Language: en Overall, the clinical parameters of the peri-implant mucosa improved using 1.2% ATV gel as an adjunct to mechanical debridement. The results of this study support the additional application of ATV gel for the treatment of peri-implant mucositis. By injecting 1.2% ATV gel into the pockets around implants with peri-implant mucositis, this clinical trial showed that it significantly reduced BOP, PD, POP, and CAL gain when used with mechanical debridement, compared with placebo gel. This may provide a new approach for treating the inflammation caused by peri-implant mucositis. The results of this study must be confirmed in long-term, multicenter, randomized, controlled clinical trials. Section title: Acknowledgments Educational score: 0.868619441986084 Domain: other Document type: Other Language: en The authors used Cloud.trinka.ai to check grammar and refine the presentation of crucial information in the introduction and discussion sections. Section title: Competing Interests Educational score: 0.9564493298530579 Domain: other Document type: Other Language: en The authors declare that they have no competing interests. Section title: Consent for Publication Educational score: 1.0266131162643433 Domain: other Document type: Other Language: fr Not applicable. Section title: Data Availability Statement Educational score: 0.8718034625053406 Domain: biomedical Document type: Other Language: en The data from the reported study are available upon request from the corresponding author. Section title: Ethical Approval Educational score: 0.9587978720664978 Domain: biomedical Document type: Other Language: en The study was approved by the Institutional Ethical Committee of the Islamic Azad University of Medical Sciences Tabriz Branch and registered with the local World Health Organization Registry Network . | Review | biomedical | en | 0.999997 |
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