Clinical safety of lidocaine in patients with cocaine-associated myocardial infarction.

STUDY OBJECTIVE: To evaluate the safety of lidocaine in the setting of cocaine-induced myocardial infarction (MI). DESIGN: A retrospective, multicenter study. SETTING: Twenty-nine university, university-affiliated, or community hospitals during a 6-year period (total of 117 cumulative hospital-years). PARTICIPANTS: Patients with cocaine-associated MI who received lidocaine in the emergency department. RESULTS: Of 29 patients who received lidocaine in the setting of cocaine-associated MI, no patient died; exhibited bradydysrhythmias, ventricular tachycardia, or ventricular fibrillation; or experienced seizures after administration of lidocaine (95% confidence interval, 0% to 11%). CONCLUSION: Despite theoretical concerns that lidocaine may enhance cocaine toxicity, the use of lidocaine in patients with cocaine-associated MI was not associated with significant cardiovascular or central nervous system toxicity.

lidocaine

cocaine

myocardial infarction

lidocaine

cocaine

myocardial infarction

MI

cocaine

MI

lidocaine

lidocaine

cocaine

MI

bradydysrhythmias

ventricular tachycardia

ventricular fibrillation

seizures

lidocaine

lidocaine

cocaine

toxicity

lidocaine

cocaine

MI

cardiovascular toxicity

central nervous system toxicity


Paclitaxel 3-hour infusion given alone and combined with carboplatin: preliminary results of dose-escalation trials.

Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) by 3-hour infusion was combined with carboplatin in a phase I/II study directed to patients with non-small cell lung cancer. Carboplatin was given at a fixed target area under the concentration-time curve of 6.0 by the Calvert formula, whereas paclitaxel was escalated in patient cohorts from 150 mg/m2 (dose level I) to 175, 200, 225, and 250 mg/m2. The 225 mg/m2 level was expanded for the phase II study since the highest level achieved (250 mg/m2) required modification because of nonhematologic toxicities (arthralgia and sensory neuropathy). Therapeutic effects were noted at all dose levels, with objective responses in 17 (two complete and 15 partial regressions) of 41 previously untreated patients. Toxicities were compared with a cohort of patients in a phase I trial of paclitaxel alone at identical dose levels. Carboplatin did not appear to add to the hematologic toxicities observed, and the paclitaxel/carboplatin combination could be dosed every 3 weeks.

Paclitaxel

carboplatin

Paclitaxel

Taxol

carboplatin

non-small cell lung cancer

Carboplatin

paclitaxel

toxicities

arthralgia

sensory neuropathy

Toxicities

paclitaxel

Carboplatin

hematologic toxicities

paclitaxel

carboplatin


The dose-dependent effect of misoprostol on indomethacin-induced renal dysfunction in well compensated cirrhosis.

Misoprostol (200 micrograms) has been shown to acutely counteract the indomethacin-induced renal dysfunction in well compensated cirrhotic patients. The aim of this study was to determine if the prophylactic value of misoprostol was dose-dependent. Parameters of renal hemodynamics and tubular sodium and water handling were assessed by clearance techniques in 26 well compensated cirrhotic patients before and after an oral combination of 50 mg of indomethacin and various doses of misoprostol. The 200-micrograms dose was able to totally abolish the deleterious renal effects of indomethacin, whereas the 800-micrograms dose resulted in significant worsening of renal hemodynamics and sodium retention. These changes were maximal in the hour immediately after medications and slowly returned toward base-line levels thereafter. These results suggest that the renal protective effects of misoprostol is dose-dependent. However, until this apparent ability of 200 micrograms of misoprostol to prevent the adverse effects of indomethacin on renal function is confirmed with chronic frequent dosing, it would be prudent to avoid nonsteroidal anti-inflammatory therapy in patients with cirrhosis.

misoprostol

indomethacin

renal dysfunction

cirrhosis

Misoprostol

indomethacin

renal dysfunction

cirrhotic

misoprostol

sodium

cirrhotic

indomethacin

misoprostol

indomethacin

sodium

misoprostol

misoprostol

indomethacin

cirrhosis


Increased frequency and severity of angio-oedema related to long-term therapy with angiotensin-converting enzyme inhibitor in two patients.

Adverse reactions to drugs are well recognized as a cause of acute or chronic urticaria, and angio-oedema. Angiotensin-converting enzyme (ACE) inhibitors, used to treat hypertension and congestive heart failure, were introduced in Europe in the middle of the eighties, and the use of these drugs has increased progressively. Soon after the introduction of ACE inhibitors, acute bouts of angio-oedema were reported in association with the use of these drugs. We wish to draw attention to the possibility of adverse reactions to ACE inhibitors after long-term use and in patients with pre-existing angio-oedema.

angio-oedema

angiotensin-converting enzyme inhibitor

urticaria

angio-oedema

hypertension

congestive heart failure

ACE inhibitors

angio-oedema

ACE inhibitors

angio-oedema


Myoclonus associated with lorazepam therapy in very-low-birth-weight infants.

Lorazepam is being used with increasing frequency as a sedative in the newborn and the young infant. Concern has been raised with regard to the safety of lorazepam in this age group, especially in very-low-birth-weight (VLBW; < 1,500 g) infants. Three young infants, all of birth weight < 1,500 g, experienced myoclonus following the intravenous administration of lorazepam. The potential neurotoxic effects of the drug (and its vehicle) in this population are discussed. Injectable lorazepam should be used with caution in VLBW infants.

Myoclonus

lorazepam

Lorazepam

lorazepam

myoclonus

lorazepam

neurotoxic

lorazepam


Transvenous right ventricular pacing during cardiopulmonary resuscitation of pediatric patients with acute cardiomyopathy.

We describe the cardiopulmonary resuscitation efforts on five patients who presented in acute circulatory failure from myocardial dysfunction. Three patients had acute viral myocarditis, one had a carbamazepine-induced acute eosinophilic myocarditis, and one had cardiac hemosiderosis resulting in acute cardiogenic shock. All patients were continuously monitored with central venous and arterial catheters in addition to routine noninvasive monitoring. An introducer sheath, a pacemaker, and sterile pacing wires were made readily available for the patients, should the need arise to terminate resistant cardiac dysrhythmias. All patients developed cardiocirculatory arrest associated with extreme hypotension and dysrhythmias within the first 48 hours of their admission to the pediatric intensive care unit (PICU). Right ventricular pacemaker wires were inserted in all of them during cardiopulmonary resuscitation (CPR). In four patients, cardiac pacing was used, resulting in a temporary captured rhythm and restoration of their cardiac output. These patients had a second event of cardiac arrest, resulting in death, within 10 to 60 minutes. In one patient, cardiac pacing was not used, because he converted to normal sinus rhythm by electrical defibrillation within three minutes of initiating CPR. We conclude that cardiac pacing during resuscitative efforts in pediatric patients suffering from acute myocardial dysfunction may not have long-term value in and of itself; however, if temporary hemodynamic stability is achieved by this procedure, it may provide additional time needed to institute other therapeutic modalities.

cardiomyopathy

circulatory failure

myocardial dysfunction

myocarditis

carbamazepine

eosinophilic myocarditis

eosinophilic

myocarditis

cardiogenic shock

dysrhythmias

hypotension

dysrhythmias

cardiac arrest

myocardial dysfunction


Efficacy and safety of granisetron, a selective 5-hydroxytryptamine-3 receptor antagonist, in the prevention of nausea and vomiting induced by high-dose cisplatin.

PURPOSE: To assess the antiemetic effects and safety profile of four different doses of granisetron (Kytril; SmithKline Beecham Pharmaceuticals, Philadelphia, PA) when administered as a single intravenous (IV) dose for prophylaxis of cisplatin-induced nausea and vomiting. PATIENTS AND METHODS: One hundred eighty-four chemotherapy-naive patients receiving high-dose cisplatin (81 to 120 mg/m2) were randomized to receive one of four granisetron doses (5, 10, 20, or 40 micrograms/kg) administered before chemotherapy. Patients were observed on an inpatient basis for 18 to 24 hours, and vital signs, nausea, vomiting, retching, and appetite were assessed. Safety analyses included incidence of adverse experiences and laboratory parameter changes. RESULTS: After granisetron doses of 5, 10, 20, and 40 micrograms/kg, a major response (< or = two vomiting or retching episodes, and no antiemetic rescue) was recorded in 23%, 57%, 58%, and 60% of patients, respectively, and a complete response (no vomiting or retching, and no antiemetic rescue) in 18%, 41%, 40%, and 47% of patients, respectively. There was a statistically longer time to first episode of nausea (P = .0015) and vomiting (P = .0001), and fewer patients were administered additional antiemetic medication in the 10-micrograms/kg dosing groups than in the 5-micrograms/kg dosing group. As granisetron dose increased, appetite return increased (P = .040). Headache was the most frequently reported adverse event (20%). CONCLUSION: A single 10-, 20-, or 40-micrograms/kg dose of granisetron was effective in controlling vomiting in 57% to 60% of patients who received cisplatin at doses greater than 81 mg/m2 and totally prevented vomiting in 40% to 47% of patients. There were no statistically significant differences in efficacy between the 10-micrograms/kg dose and the 20- and 40-micrograms/kg doses. Granisetron was well tolerated at all doses.

granisetron

nausea

vomiting

cisplatin

granisetron

Kytril

cisplatin

nausea

vomiting

cisplatin

granisetron

nausea

vomiting

granisetron

vomiting

vomiting

nausea

vomiting

granisetron

Headache

granisetron

vomiting

cisplatin

vomiting

Granisetron


Adverse interaction between clonidine and verapamil.

OBJECTIVE: To report two cases of a possible adverse interaction between clonidine and verapamil resulting in atrioventricular (AV) block in both patients and severe hypotension in one patient. CASE SUMMARIES: A 54-year-old woman with hyperaldosteronism was treated with verapamil 480 mg/d and spironolactone 100 mg/d. After the addition of a minimal dose of clonidine (0.15 mg bid), she developed complete AV block and severe hypotension, which resolved upon cessation of all medications. A 65-year-old woman was treated with extended-release verapamil 240 mg/d. After the addition of clonidine 0.15 mg bid she developed complete AV block, which resolved after all therapy was stopped. DISCUSSION: An adverse interaction between clonidine and verapamil has not been reported previously. We describe two such cases and discuss the various mechanisms that might cause such an interaction. Clinicians should be acquainted with this possibly fatal interaction between two commonly used antihypertensive drugs. CONCLUSIONS: Caution is recommended in combining clonidine and verapamil therapy, even in patients who do not have sinus or AV node dysfunction. The two drugs may act synergistically on both the AV node and the peripheral circulation.

clonidine

verapamil

clonidine

verapamil

atrioventricular (AV) block

hypotension

hyperaldosteronism

verapamil

spironolactone

clonidine

AV block

hypotension

verapamil

clonidine

AV block

clonidine

verapamil

clonidine

verapamil


Pharmacological studies on a new dihydrothienopyridine calcium antagonist, S-312-d. 5th communication: anticonvulsant effects in mice.

S-312, S-312-d, but not S-312-l, L-type calcium channel antagonists, showed anticonvulsant effects on the audiogenic tonic convulsions in DBA/2 mice; and their ED50 values were 18.4 (12.8-27.1) mg/kg, p.o. and 15.0 (10.2-23.7) mg/kg, p.o., respectively, while that of flunarizine was 34.0 (26.0-44.8) mg/kg, p.o. Although moderate anticonvulsant effects of S-312-d in higher doses were observed against the clonic convulsions induced by pentylenetetrazole (85 mg/kg, s.c.) or bemegride (40 mg/kg, s.c.), no effects were observed in convulsions induced by N-methyl-D-aspartate, picrotoxin, or electroshock in Slc:ddY mice. S-312-d may be useful in the therapy of certain types of human epilepsy.

dihydrothienopyridine calcium

calcium

audiogenic tonic convulsions

flunarizine

convulsions

pentylenetetrazole

bemegride

convulsions

N-methyl-D-aspartate

picrotoxin

epilepsy


Transmural myocardial infarction with sumatriptan.

For sumatriptan, tightness in the chest caused by an unknown mechanism has been reported in 3-5% of users. We describe a 47-year-old woman with an acute myocardial infarction after administration of sumatriptan 6 mg subcutaneously for cluster headache. The patient had no history of underlying ischaemic heart disease or Prinzmetal's angina. She recovered without complications.

myocardial infarction

sumatriptan

sumatriptan

myocardial infarction

sumatriptan

cluster headache

ischaemic heart disease

Prinzmetal's angina


Flumazenil induces seizures and death in mixed cocaine-diazepam intoxications.

STUDY HYPOTHESIS: Administration of the benzodiazepine antagonist flumazenil may unmask seizures in mixed cocaine-benzodiazepine intoxication. DESIGN: Male Sprague-Dawley rats received 100 mg/kg cocaine IP alone, 5 mg/kg diazepam alone, or a combination of diazepam and cocaine. Three minutes later, groups were challenged with vehicle or flumazenil 5 or 10 mg/kg IP. Animal behavior, seizures (time to and incidence), death (time to and incidence), and cortical EEG tracings were recorded. INTERVENTIONS: Administration of flumazenil to animals after they had received a combination dose of cocaine and diazepam. RESULTS: In group 1, animals received cocaine followed by vehicle. This resulted in 100% developing seizures and death. Group 2 received diazepam alone followed by vehicle. Animals became somnolent and none died. Group 3 received diazepam followed by 5 mg/kg flumazenil. Animals became somnolent after diazepam and then active after flumazenil administration. In group 4, a combination of cocaine and diazepam was administered simultaneously. This resulted in no overt or EEG-detectable seizures and a 50% incidence of death. Group 5 received a similar combination of cocaine and diazepam, followed later by 5 mg/kg flumazenil. This resulted in an increased incidence of seizures, 90% (P < .01), and death, 100% (P < or = .01), compared with group 4. Group 6 received cocaine and diazepam followed by 10 mg/kg flumazenil. This also resulted in an increased incidence of seizures, 90% (P < or = .01), and death, 90% (P < or = .05), compared with group 4. CONCLUSION: Flumazenil can unmask seizures and increase the incidence of death in a model of combined cocaine-diazepam intoxications.

Flumazenil

seizures

cocaine

diazepam

benzodiazepine

flumazenil

seizures

cocaine

benzodiazepine

cocaine

diazepam

diazepam

cocaine

flumazenil

seizures

flumazenil

cocaine

diazepam

cocaine

seizures

diazepam

diazepam

flumazenil

diazepam

flumazenil

cocaine

diazepam

seizures

cocaine

diazepam

flumazenil

seizures

cocaine

diazepam

flumazenil

seizures

Flumazenil

seizures

cocaine

diazepam


Mechanisms for protective effects of free radical scavengers on gentamicin-mediated nephropathy in rats.

Studies were performed to examine the mechanisms for the protective effects of free radical scavengers on gentamicin (GM)-mediated nephropathy. Administration of GM at 40 mg/kg sc for 13 days to rats induced a significant reduction in renal blood flow (RBF) and inulin clearance (CIn) as well as marked tubular damage. A significant reduction in urinary guanosine 3',5'-cyclic monophosphate (cGMP) excretion and a significant increase in renal cortical renin and endothelin-1 contents were also observed in GM-mediated nephropathy. Superoxide dismutase (SOD) or dimethylthiourea (DMTU) significantly lessened the GM-induced decrement in CIn. The SOD-induced increase in glomerular filtration rate was associated with a marked improvement in RBF, an increase in urinary cGMP excretion, and a decrease in renal renin and endothelin-1 content. SOD did not attenuate the tubular damage. In contrast, DMTU significantly reduced the tubular damage and lipid peroxidation, but it did not affect renal hemodynamics and vasoactive substances. Neither SOD nor DMTU affected the renal cortical GM content in GM-treated rats. These results suggest that 1) both SOD and DMTU have protective effects on GM-mediated nephropathy, 2) the mechanisms for the protective effects differ for SOD and DMTU, and 3) superoxide anions play a critical role in GM-induced renal vasoconstriction.

gentamicin

nephropathy

gentamicin

GM

nephropathy

GM

tubular damage

guanosine 3',5'-cyclic monophosphate

cGMP

GM

nephropathy

Superoxide

dimethylthiourea

DMTU

GM

cGMP

tubular damage

DMTU

tubular damage

DMTU

GM

GM

DMTU

GM

nephropathy

DMTU

superoxide

GM


Assessment of cardiomyocyte DNA synthesis during hypertrophy in adult mice.

The ability of cardiomyocytes to synthesize DNA in response to experimentally induced cardiac hypertrophy was assessed in adult mice. Isoproterenol delivered by osmotic minipump implantation in adult C3Heb/FeJ mice resulted in a 46% increase in heart weight and a 19.3% increase in cardiomyocyte area. No DNA synthesis, as assessed by autoradiographic analysis of isolated cardiomyocytes, was observed in control or hypertrophic hearts. A survey of 15 independent inbred strains of mice revealed that ventricular cardiomyocyte nuclear number ranged from 3 to 13% mononucleate, suggesting that cardiomyocyte terminal differentiation is influenced directly or indirectly by genetic background. To determine whether the capacity for reactive DNA synthesis was also subject to genetic regulation, cardiac hypertrophy was induced in the strains of mice comprising the extremes of the nuclear number survey. These data indicate that adult mouse atrial and ventricular cardiomyocytes do not synthesize DNA in response to isoproterenol-induced cardiac hypertrophy.

hypertrophy

cardiac hypertrophy

Isoproterenol

hypertrophic hearts

cardiac hypertrophy

isoproterenol

cardiac hypertrophy


Central cardiovascular effects of AVP and ANP in normotensive and spontaneously hypertensive rats.

The purpose of the present study was to compare influence of central arginine vasopressin (AVP) and of atrial natriuretic peptide (ANP) on control of arterial blood pressure (MAP) and heart rate (HR) in normotensive (WKY) and spontaneously hypertensive (SHR) rats. Three series of experiments were performed on 30 WKY and 30 SHR, chronically instrumented with guide tubes in the lateral ventricle (LV) and arterial and venous catheters. MAP and HR were monitored before and after i.v. injections of either vehicle or 1, 10 and 50 ng of AVP and 25, 125 and 500 ng of ANP. Sensitivity of cardiac component of baroreflex (CCB), expressed as a slope of the regression line was determined from relationships between systolic arterial pressure (SAP) and HR period (HRp) during phenylephrine (Phe)-induced hypertension and sodium nitroprusside (SN)-induced hypotension. CCB was measured before and after administration of either vehicle, AVP, ANP, or both peptides together. Increases of MAP occurred after LV administration of 1, 10 and 50 ng of AVP in WKY and of 10 and 50 ng in SHR. ANP did not cause significant changes in MAP in both strains as compared to vehicle, but it abolished AVP-induced MAP increase in WKY and SHR. CCB was reduced in WKY and SHR after LV administration of AVP during SN-induced hypotension. In SHR but not in WKY administration of ANP, AVP and ANP + AVP decreased CCB during Phe-induced MAP elevation. The results indicate that centrally applied AVP and ANP exert differential effects on blood pressure and baroreflex control of heart rate in WKY and SHR and suggest interaction of these two peptides in blood pressure regulation at the level of central nervous system.

AVP

hypertensive

arginine vasopressin

AVP

hypertensive

AVP

phenylephrine

Phe

hypertension

sodium nitroprusside

SN

hypotension

AVP

AVP

AVP

AVP

SN

hypotension

AVP

AVP

Phe

AVP


Cutaneous exposure to warfarin-like anticoagulant causing an intracerebral hemorrhage: a case report.

A case of intercerebral hematoma due to warfarin-induced coagulopathy is presented. The 39-year-old woman had spread a warfarin-type rat poison around her house weekly using her bare hands, with no washing post application. Percutaneous absorption of warfarin causing coagulopathy, reported three times in the past, is a significant risk if protective measures, such as gloves, are not used. An adverse drug interaction with piroxicam, which she took occasionally, may have exacerbated the coagulopathy.

warfarin

intracerebral hemorrhage

hematoma

warfarin

coagulopathy

warfarin

warfarin

coagulopathy

piroxicam

coagulopathy


Pediatric heart transplantation without chronic maintenance steroids.

From 1986 to February 1993, 40 children aged 2 months to 18 years (average age 10.4 +/- 5.8 years) underwent heart transplantation. Indications for transplantation were idiopathic cardiomyopathy (52%), congenital heart disease (35%) with and without prior repair (71% and 29%, respectively), hypertrophic cardiomyopathy (5%), valvular heart disease (3%), and doxorubicin cardiomyopathy (5%). Patients were managed with cyclosporine and azathioprine. No prophylaxis with antilymphocyte globulin was used. Steroids were given to 39% of patients for refractory rejection, but weaning was always attempted and generally successful (64%). Five patients (14%) received maintenance steroids. Four patients died in the perioperative period and one died 4 months later. There have been no deaths related to rejection or infection. Average follow-up was 36 +/- 19 months (range 1 to 65 months). Cumulative survival is 88% at 5 years. In patients less than 7 years of age, rejection was monitored noninvasively. In the first postoperative month, 89% of patients were treated for rejection. Freedom from serious infections was 83% at 1 month and 65% at 1 year. Cytomegalovirus infections were treated successfully with ganciclovir in 11 patients. No impairment of growth was observed in children who underwent transplantation compared with a control population. Twenty-one patients (60%) have undergone annual catheterizations and no sign of graft atherosclerosis has been observed. Seizures occurred in five patients (14%) and hypertension was treated in 10 patients (28%). No patient was disabled and no lymphoproliferative disorder was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

steroids

idiopathic cardiomyopathy

congenital heart disease

hypertrophic cardiomyopathy

valvular heart disease

doxorubicin

cardiomyopathy

cyclosporine

azathioprine

Steroids

steroids

infection

infections

Cytomegalovirus infections

ganciclovir

atherosclerosis

Seizures

hypertension

lymphoproliferative disorder


Delirium during fluoxetine treatment. A case report.

The correlation between high serum tricyclic antidepressant concentrations and central nervous system side effects has been well established. Only a few reports exist, however, on the relationship between the serum concentrations of selective serotonin reuptake inhibitors (SSRIs) and their toxic effects. In some cases, a high serum concentration of citalopram (> 600 nmol/L) in elderly patients has been associated with increased somnolence and movement difficulties. Widespread cognitive disorders, such as delirium, have not been previously linked with high blood levels of SSRIs. In this report, we describe a patient with acute hyperkinetic delirium connected with a high serum total fluoxetine (fluoxetine plus desmethylfluoxetine) concentration.

Delirium

fluoxetine

serotonin

citalopram

somnolence

movement difficulties

cognitive disorders

delirium

hyperkinetic

delirium

fluoxetine

fluoxetine

desmethylfluoxetine


Pulmonary edema and shock after high-dose aracytine-C for lymphoma; possible role of TNF-alpha and PAF.

Four out of 23 consecutive patients treated with high-dose Ara-C for lymphomas in our institution developed a strikingly similar syndrome during the perfusion. It was characterized by the onset of fever, diarrhea, shock, pulmonary edema, acute renal failure, metabolic acidosis, weight gain and leukocytosis. Thorough bacteriological screening failed to provide evidence of infection. Sequential biological assays of IL-1, IL-2, TNF and PAF were performed during Ara-C infusion to ten patients, including the four who developed the syndrome. TNF and PAF activity was found in the serum of respectively two and four of the cases, but not in the six controls. As TNF and PAF are thought to be involved in the development of septic shock and adult respiratory distress syndrome, we hypothesize that high-dose Ara-C may be associated with cytokine release.

Pulmonary edema

shock

aracytine-C

lymphoma

Ara-C

lymphomas

fever

diarrhea

shock

pulmonary edema

acute renal failure

metabolic acidosis

weight gain

leukocytosis

infection

Ara-C

shock

adult respiratory distress syndrome

Ara-C


Protective effect of clentiazem against epinephrine-induced cardiac injury in rats.

We investigated the effects of clentiazem, a 1,5-benzothiazepine calcium antagonist, on epinephrine-induced cardiomyopathy in rats. With 2-week chronic epinephrine infusion, 16 of 30 rats died within 4 days, and severe ischemic lesions and fibrosis of the left ventricles were observed. In epinephrine-treated rats, left atrial and left ventricular papillary muscle contractile responses to isoproterenol were reduced, but responses to calcium were normal or enhanced compared to controls. Left ventricular alpha and beta adrenoceptor densities were also reduced compared to controls. Treatment with clentiazem prevented epinephrine-induced death (P < .05), and attenuated the ventricular ischemic lesions and fibrosis, in a dose-dependent manner. Left atrial and left ventricular papillary muscle contractile responses to isoproterenol were reduced compared to controls in groups treated with clentiazem alone, but combined with epinephrine, clentiazem restored left atrial responses and enhanced left ventricular papillary responses to isoproterenol. On the other hand clentiazem did not prevent epinephrine-induced down-regulation of alpha and beta adrenoceptors. Interestingly, clentiazem, infused alone, resulted in decreased adrenergic receptor densities in the left ventricle. Clentiazem also did not prevent the enhanced responses to calcium seen in the epinephrine-treated animals, although the high dose of clentiazem partially attenuated the maximal response to calcium compared to epinephrine-treated animals. In conclusion, clentiazem attenuated epinephrine-induced cardiac injury, possibly through its effect on the adrenergic pathway.

clentiazem

epinephrine

cardiac injury

clentiazem

calcium

epinephrine

cardiomyopathy

epinephrine

ischemic lesions

fibrosis

epinephrine

isoproterenol

calcium

clentiazem

epinephrine

ischemic lesions

fibrosis

isoproterenol

clentiazem

epinephrine

clentiazem

isoproterenol

clentiazem

epinephrine

clentiazem

Clentiazem

calcium

epinephrine

clentiazem

calcium

epinephrine

clentiazem

epinephrine

cardiac injury


Cocaine induced myocardial ischemia.

We report a case of myocardial ischemia induced by cocaine. The ischemia probably induced by coronary artery spasm was reversed by nitroglycerin and calcium blocking agents.

Cocaine

myocardial ischemia

myocardial ischemia

cocaine

ischemia

coronary artery spasm

nitroglycerin

calcium


Doxorubicin-induced cardiotoxicity monitored by ECG in freely moving mice. A new model to test potential protectors.

In laboratory animals, histology is most commonly used to study doxorubicin-induced cardiotoxicity. However, for monitoring during treatment, large numbers of animals are needed. Recently we developed a new method to measure ECG values in freely moving mice by telemetry. With this model we investigated the effect of chronic doxorubicin administration on the ECG of freely moving BALB/c mice and the efficacy of ICRF-187 as a protective agent. The ST interval significantly widened from 15.0 +/- 1.5 to 56.8 +/- 11.8 ms in week 10 (7 weekly doses of 4 mg/kg doxorubicin given i.v. plus 3 weeks of observation). The ECG of the control animals did not change during the entire study. After sacrifice the hearts of doxorubicin-treated animals were enlarged and the atria were hypertrophic. As this schedule exerted more toxicity than needed to investigate protective agents, the protection of ICRF-187 was determined using a dose schedule with lower general toxicity (6 weekly doses of 4 mg/kg doxorubicin given i.v. plus 2 weeks of observation). On this schedule, the animals' hearts appeared normal after sacrifice and ICRF-187 (50 mg/kg given i.p. 1 h before doxorubicin) provided almost full protection. These data were confirmed by histology. The results indicate that this new model is very sensitive and enables monitoring of the development of cardiotoxicity with time. These findings result in a model that allows the testing of protectors against doxorubicin-induced cardiotoxicity as demonstrated by the protection provided by ICRF-187.

Doxorubicin

cardiotoxicity

doxorubicin

cardiotoxicity

doxorubicin

doxorubicin

doxorubicin

hypertrophic

toxicity

toxicity

doxorubicin

doxorubicin

cardiotoxicity

doxorubicin

cardiotoxicity


Epinephrine dysrhythmogenicity is not enhanced by subtoxic bupivacaine in dogs.

Since bupivacaine and epinephrine may both precipitate dysrhythmias, circulating bupivacaine during regional anesthesia could potentiate dysrhythmogenic effects of epinephrine. We therefore examined whether bupivacaine alters the dysrhythmogenicity of subsequent administration of epinephrine in conscious, healthy dogs and in anesthetized dogs with myocardial infarction. Forty-one conscious dogs received 10 micrograms.kg-1.min-1 epinephrine. Seventeen animals responded with ventricular tachycardia (VT) within 3 min. After 3 h, these responders randomly received 1 or 2 mg/kg bupivacaine or saline over 5 min, followed by 10 micrograms.kg-1.min-1 epinephrine. In the bupivacaine groups, epinephrine caused fewer prodysrhythmic effects than without bupivacaine. VT appeared in fewer dogs and at a later time, and there were more sinoatrial beats and less ectopies. Epinephrine shortened QT less after bupivacaine than in control animals. One day after experimental myocardial infarction, six additional halothane-anesthetized dogs received 4 micrograms.kg-1.min-1 epinephrine until VT appeared. After 45 min, 1 mg/kg bupivacaine was injected over 5 min, again followed by 4 micrograms.kg-1.min-1 epinephrine. In these dogs, the prodysrhythmic response to epinephrine was also mitigated by preceding bupivacaine. Bupivacaine antagonizes epinephrine dysrhythmogenicity in conscious dogs susceptible to VT and in anesthetized dogs with spontaneous postinfarct dysrhythmias. There is no evidence that systemic subtoxic bupivacaine administration enhances the dysrhythmogenicity of subsequent epinephrine.

Epinephrine

bupivacaine

bupivacaine

epinephrine

dysrhythmias

bupivacaine

epinephrine

bupivacaine

epinephrine

myocardial infarction

epinephrine

ventricular tachycardia

VT

bupivacaine

epinephrine

bupivacaine

epinephrine

bupivacaine

VT

Epinephrine

bupivacaine

myocardial infarction

halothane

epinephrine

VT

bupivacaine

epinephrine

epinephrine

bupivacaine

Bupivacaine

epinephrine

VT

dysrhythmias

bupivacaine

epinephrine


Milk-alkali syndrome induced by 1,25(OH)2D in a patient with hypoparathyroidism.

Milk-alkali syndrome was first described 70 years ago in the context of the treatment of peptic ulcer disease with large amounts of calcium and alkali. Although with current ulcer therapy (H-2 blockers, omeprazole, and sucralfate), the frequency of milk-alkali syndrome has decreased significantly, the classic triad of hypercalcemia, alkalosis, and renal impairment remains the hallmark of the syndrome. Milk-alkali syndrome can present serious and occasionally life-threatening illness unless diagnosed and treated appropriately. This article presents a patient with hypoparathyroidism who was treated with calcium carbonate and calcitriol resulting in two admissions to the hospital for milk-alkali syndrome. The patient was successfully treated with intravenous pamidronate on his first admission and with hydrocortisone on the second. This illustrates intravenous pamidronate as a valuable therapeutic tool when milk-alkali syndrome presents as hypercalcemic emergency.

Milk-alkali syndrome

hypoparathyroidism

Milk-alkali syndrome

peptic ulcer disease

calcium

alkali

ulcer

omeprazole

sucralfate

milk-alkali syndrome

hypercalcemia

alkalosis

renal impairment

Milk-alkali syndrome

hypoparathyroidism

calcium carbonate

calcitriol

milk-alkali syndrome

pamidronate

hydrocortisone

pamidronate

milk-alkali syndrome

hypercalcemic emergency


Encephalopathy during amitriptyline therapy: are neuroleptic malignant syndrome and serotonin syndrome spectrum disorders?

This report describes a case of encephalopathy developed in the course of amitriptyline therapy, during a remission of unipolar depression. This patient could have been diagnosed as having either neuroleptic malignant syndrome (NMS) or serotonin syndrome (SS). The major determinant of the symptoms may have been dopamine/serotonin imbalance in the central nervous system. The NMS-like encephalopathy that develops in association with the use of antidepressants indicates that NMS and SS are spectrum disorders induced by drugs with both antidopaminergic and serotonergic effects.

Encephalopathy

amitriptyline

neuroleptic malignant syndrome

serotonin syndrome

encephalopathy

amitriptyline

unipolar depression

neuroleptic malignant syndrome

NMS

serotonin syndrome

SS

dopamine

serotonin

NMS

encephalopathy

NMS

SS


Genetic separation of tumor growth and hemorrhagic phenotypes in an estrogen-induced tumor.

Chronic administration of estrogen to the Fischer 344 (F344) rat induces growth of large, hemorrhagic pituitary tumors. Ten weeks of diethylstilbestrol (DES) treatment caused female F344 rat pituitaries to grow to an average of 109.2 +/- 6.3 mg (mean +/- SE) versus 11.3 +/- 1.4 mg for untreated rats, and to become highly hemorrhagic. The same DES treatment produced no significant growth (8.9 +/- 0.5 mg for treated females versus 8.7 +/- 1.1 for untreated females) or morphological changes in Brown Norway (BN) rat pituitaries. An F1 hybrid of F344 and BN exhibited significant pituitary growth after 10 weeks of DES treatment with an average mass of 26.3 +/- 0.7 mg compared with 8.6 +/- 0.9 mg for untreated rats. Surprisingly, the F1 hybrid tumors were not hemorrhagic and had hemoglobin content and outward appearance identical to that of BN. Expression of both growth and morphological changes is due to multiple genes. However, while DES-induced pituitary growth exhibited quantitative, additive inheritance, the hemorrhagic phenotype exhibited recessive, epistatic inheritance. Only 5 of the 160 F2 pituitaries exhibited the hemorrhagic phenotype; 36 of the 160 F2 pituitaries were in the F344 range of mass, but 31 of these were not hemorrhagic, indicating that the hemorrhagic phenotype is not merely a consequence of extensive growth. The hemorrhagic F2 pituitaries were all among the most massive, indicating that some of the genes regulate both phenotypes.

tumor

hemorrhagic

estrogen

tumor

estrogen

hemorrhagic

pituitary tumors

diethylstilbestrol

DES

hemorrhagic

DES

DES

tumors

hemorrhagic

DES

hemorrhagic

hemorrhagic

hemorrhagic

hemorrhagic

hemorrhagic


Increased expression of neuronal nitric oxide synthase in bladder afferent pathways following chronic bladder irritation.

Immunocytochemical techniques were used to examine alterations in the expression of neuronal nitric oxide synthase (NOS) in bladder pathways following acute and chronic irritation of the urinary tract of the rat. Chemical cystitis was induced by cyclophosphamide (CYP) which is metabolized to acrolein, an irritant eliminated in the urine. Injection of CYP (n = 10, 75 mg/kg, i.p.) 2 hours prior to perfusion (acute treatment) of the animals increased Fos-immunoreactivity (IR) in neurons in the dorsal commissure, dorsal horn, and autonomic regions of spinal segments (L1-L2 and L6-S1) which receive afferent inputs from the bladder, urethra, and ureter. Fos-IR in the spinal cord was not changed in rats receiving chronic CYP treatment (n = 15, 75 mg/kg, i.p., every 3rd day for 2 weeks). In control animals and in animals treated acutely with CYP, only small numbers of NOS-IR cells (0.5-0.7 cell profiles/sections) were detected in the L6-S1 dorsal root ganglia (DRG). Chronic CYP administration significantly (P < or = .002) increased bladder weight by 60% and increased (7- to 11-fold) the numbers of NOS-immunoreactive (IR) afferent neurons in the L6-S1 DRG. A small increase (1.5-fold) also occurred in the L1 DRG, but no change was detected in the L2 and L5 DRG. Bladder afferent cells in the L6-S1 DRG labeled by Fluorogold (40 microliters) injected into the bladder wall did not exhibit NOS-IR in control animals; however, following chronic CYP administration, a significant percentage of bladder afferent neurons were NOS-IR: L6 (19.8 +/- 4.6%) and S1 (25.3 +/- 2.9%). These results indicate that neuronal gene expression in visceral sensory pathways can be upregulated by chemical irritation of afferent receptors in the urinary tract and/or that pathological changes in the urinary tract can initiate chemical signals that alter the chemical properties of visceral afferent neurons.

nitric oxide

bladder irritation

nitric oxide

irritation of the urinary tract

cystitis

cyclophosphamide

CYP

acrolein

CYP

CYP

CYP

CYP

CYP


Effects of a new calcium antagonist, CD-832, on isoproterenol-induced myocardial ischemia in dogs with partial coronary stenosis.

Effects of CD-832 on isoproterenol (ISO)-induced myocardial ischemia were studied in dogs with partial coronary stenosis of the left circumflex coronary artery and findings were compared with those for nifedipine or diltiazem. In the presence of coronary artery stenosis, 3-min periods of intracoronary ISO infusion (10 ng/kg/min) increased heart rate and maximal rate of left ventricular pressure rise, which resulted in a decrease in percentage segmental shortening and ST-segment elevation of the epicardial electrocardiogram. After the control ISO infusion with stenosis was performed, equihypotensive doses of CD-832 (3 and 10 micrograms/kg/min, n = 7), nifedipine (1 and 3 micrograms/kg/min, n = 9) or diltiazem (10 and 30 micrograms/kg/min, n = 7) were infused 5 min before and during the second and third ISO infusion. Both CD-832 and diltiazem, but not nifedipine, significantly reduced the increase in heart rate induced by ISO infusion. In contrast to nifedipine, CD-832 (10 micrograms/kg/min) prevented the decrease in percentage segmental shortening from 32 +/- 12% to 115 +/- 26% of the control value (P < .01) and ST-segment elevation from 5.6 +/- 1.0 mV to 1.6 +/- 1.3 mV (P < .01) at 3 min after ISO infusion with stenosis. Diltiazem (30 micrograms/kg/min) also prevented the decrease in percentage segmental shortening from 34 +/- 14% to 63 +/- 18% of the control value (P < .05) and ST-segment elevation from 4.7 +/- 0.7 mV to 2.1 +/- 0.7 mV (P < .01) at 3 min after ISO infusion with stenosis. These data show that CD-832 improves myocardial ischemia during ISO infusion with stenosis and suggest that the negative chronotropic property of CD-832 plays a major role in the beneficial effects of CD-832.

calcium

isoproterenol

myocardial ischemia

coronary stenosis

isoproterenol

ISO

myocardial ischemia

coronary stenosis

nifedipine

diltiazem

coronary artery stenosis

ISO

ISO

stenosis

nifedipine

diltiazem

ISO

diltiazem

nifedipine

ISO

nifedipine

ISO

stenosis

Diltiazem

ISO

stenosis

myocardial ischemia

ISO

stenosis


The effect of recombinant human insulin-like growth factor-I on chronic puromycin aminonucleoside nephropathy in rats.

We recently demonstrated that recombinant hGH exacerbates renal functional and structural injury in chronic puromycin aminonucleoside (PAN) nephropathy, an experimental model of glomerular disease. Therefore, we examined whether recombinant human (rh) IGF-I is a safer alternative for the treatment of growth failure in rats with chronic PAN nephropathy. The glomerulopathy was induced by seven serial injections of PAN over 12 wk. Experimental animals (n = 6) received rhIGF-I, 400 micrograms/d, whereas control rats (n = 6) received the vehicle. rhIGF-I improved weight gain by 14% (p < 0.05), without altering hematocrit or blood pressure in rats with renal disease. Urinary protein excretion was unaltered by rhIGF-I treatment in rats with chronic PAN nephropathy. After 12 wk, the inulin clearance was higher in rhIGF-I-treated rats, 0.48 +/- 0.08 versus 0.24 +/- 0.06 mL/min/100 g of body weight in untreated PAN nephropathy animals, p < 0.05. The improvement in GFR was not associated with enhanced glomerular hypertrophy or increased segmental glomerulosclerosis, tubulointerstitial injury, or renal cortical malondialdehyde content. In rats with PAN nephropathy, administration of rhIGF-I increased IGF-I and GH receptor gene expression, without altering the steady state level of IGF-I receptor mRNA. In normal rats with intact kidneys, rhIGF-I administration (n = 4) did not alter weight gain, blood pressure, proteinuria, GFR, glomerular planar area, renal cortical malondialdehyde content, or glomerular or tubulointerstitial damage, compared with untreated animals (n = 4). rhIGF-I treatment reduced the steady state renal IGF-I mRNA level but did not modify gene expression of the IGF-I or GH receptors. We conclude that: 1) administration of rhIGF-I improves growth and GFR in rats with chronic PAN nephropathy and 2) unlike rhGH, long-term use of rhIGF-I does not worsen renal functional and structural injury in this disease model.

puromycin aminonucleoside

nephropathy

puromycin aminonucleoside

PAN

nephropathy

glomerular disease

growth failure

PAN

nephropathy

glomerulopathy

PAN

renal disease

PAN

nephropathy

PAN

nephropathy

glomerular hypertrophy

glomerulosclerosis

tubulointerstitial injury

malondialdehyde

PAN

nephropathy

proteinuria

malondialdehyde

tubulointerstitial damage

PAN

nephropathy


Nefiracetam (DM-9384) reverses apomorphine-induced amnesia of a passive avoidance response: delayed emergence of the memory retention effects.

Nefiracetam is a novel pyrrolidone derivative which attenuates scopolamine-induced learning and post-training consolidation deficits. Given that apomorphine inhibits passive avoidance retention when given during training or in a defined 10-12h post-training period, we evaluated the ability of nefiracetam to attenuate amnesia induced by dopaminergic agonism. A step-down passive avoidance paradigm was employed and nefiracetam (3 mg/kg) and apomorphine (0.5 mg/kg) were given alone or in combination during training and at the 10-12h post-training period of consolidation. Co-administration of nefiracetam and apomorphine during training or 10h thereafter produced no significant anti-amnesic effect. However, administration of nefiracetam during training completely reversed the amnesia induced by apomorphine at the 10h post-training time and the converse was also true. These effects were not mediated by a dopaminergic mechanism as nefiracetam, at millimolar concentrations, failed to displace either [3H]SCH 23390 or [3H]spiperone binding from D1 or D2 dopamine receptor subtypes, respectively. It is suggested that nefiracetam augments molecular processes in the early stages of events which ultimately lead to consolidation of memory.

Nefiracetam

apomorphine

amnesia

Nefiracetam

pyrrolidone

scopolamine

apomorphine

nefiracetam

amnesia

nefiracetam

apomorphine

nefiracetam

apomorphine

nefiracetam

amnesia

apomorphine

nefiracetam

SCH 23390

spiperone

dopamine

nefiracetam


Human corticotropin-releasing hormone and thyrotropin-releasing hormone modulate the hypercapnic ventilatory response in humans.

Human corticotropin-releasing hormone (hCRH) and thyrotropin-releasing hormone (TRH) are known to stimulate ventilation after i.v. administration in humans. In a placebo-controlled, single-blind study we aimed to clarify if both peptides act by altering central chemosensitivity. Two subsequent CO2-rebreathing tests were performed in healthy young volunteers. During the first test 0.9% NaCl was given i.v.; during the second test 200 micrograms of hCRH (n = 12) or 400 micrograms of TRH (n = 6) was administered i.v. Nine subjects received 0.9% NaCl i.v. during both rebreathing manoeuvres. The CO2-response curves for the two tests were compared within the same subject. In the hCRH group a marked parallel shift of the CO2-response curve to the left was observed after hCRH (P < 0.01). The same effect occurred following TRH but was less striking (P = 0.05). hCRH and TRH caused a reduction in the CO2 threshold. The CO2-response curves in the control group were nearly identical. The results indicate an additive effect of both releasing hormones on the hypercapnic ventilatory response in humans, presumably independent of central chemosensitivity.

corticotropin

thyrotropin

hypercapnic

corticotropin

thyrotropin

NaCl

NaCl

hypercapnic


Lamivudine is effective in suppressing hepatitis B virus DNA in Chinese hepatitis B surface antigen carriers: a placebo-controlled trial.

Lamivudine is a novel 2',3'-dideoxy cytosine analogue that has potent inhibitory effects on hepatitis B virus replication in vitro and in vivo. We performed a single-blind, placebo-controlled study to assess its effectiveness and safety in Chinese hepatitis B surface antigen (HBsAg) carriers. Forty-two Chinese HBsAg carriers were randomized to receive placebo (6 patients) or lamivudine orally in dosages of 25 mg, 100 mg, or 300 mg daily (12 patients for each dosage). The drug was given for 4 weeks. The patients were closely monitored clinically, biochemically, and serologically up to 4 weeks after drug treatment. All 36 patients receiving lamivudine had a decrease in hepatitis B virus (HBV) DNA values of >90% (P < .001 compared with placebo). Although 25 mg of lamivudine was slightly less effective than 100 mg (P = .011) and 300 mg (P = .005), it still induced 94% suppression of HBV DNA after the fourth week of therapy. HBV DNA values returned to pretreatment levels within 4 weeks of cessation of therapy. There was no change in the hepatitis B e antigen status or in aminotransferase levels. No serious adverse events were observed. In conclusion, a 4-week course of lamivudine was safe and effective in suppression of HBV DNA in Chinese HBsAg carriers. The suppression was >90% but reversible. Studies with long-term lamivudine administration should be performed to determine if prolonged suppression of HBV DNA can be achieved.

Lamivudine

hepatitis B

hepatitis B surface antigen

Lamivudine

2',3'-dideoxy cytosine

hepatitis B

hepatitis B surface antigen

HBsAg

HBsAg

lamivudine

lamivudine

hepatitis B

lamivudine

hepatitis B

lamivudine

HBsAg

lamivudine


Population-based study of risk of venous thromboembolism associated with various oral contraceptives.

BACKGROUND: Four studies published since December, 1995, reported that the incidence of venous thromboembolism (VTE) was higher in women who used oral contraceptives (OCs) containing the third-generation progestagens gestodene or desogestrel than in users of OCs containing second-generation progestagens. However, confounding and bias in the design of these studies may have affected the findings. The aim of our study was to re-examine the association between risk of VTE and OC use with a different study design and analysis to avoid some of the bias and confounding of the earlier studies. METHODS: We used computer records of patients from 143 general practices in the UK. The study was based on the medical records of about 540,000 women born between 1941 and 1981. All women who had a recorded diagnosis of deep-vein thrombosis, venous thrombosis not otherwise specified, or pulmonary embolus during the study period, and who had been treated with an anticoagulant were identified as potential cases of VTE. We did a cohort analysis to estimate and compare incidence of VTE in users of the main OC preparations, and a nested case-control study to calculate the odds ratios of VTE associated with use of different types of OC, after adjustment for potential confounding factors. In the case-control study, we matched cases to controls by exact year of birth, practice, and current use of OCs. We used a multiple logistic regression model that included body-mass index, number of cycles, change in type of OC prescribed within 3 months of the event, previous pregnancy, and concurrent disease. FINDINGS: 85 women met the inclusion criteria for VTE, two of whom were users of progestagen-only OCs. Of the 83 cases of VTE associated with use of combined OCs, 43 were recorded as deep-vein thrombosis, 35 as pulmonary thrombosis, and five as venous thrombosis not otherwise specified. The crude rate of VTE per 10,000 woman-years was 4.10 in current users of any OC, 3.10 in users of second-generation OCs, and 4.96 in users of third-generation preparations. After adjustment for age, the rate ratio of VTE in users of third-generation relative to second-generation OCs was 1.68 (95% CI 1.04-2.75). Logistic regression showed no significant difference in the risk of VTE between users of third-generation and second-generation OCs. Among users of third-generation progestagens, the risk of VTE was higher in users of desogestrel with 20 g ethinyloestradiol than in users of gestodene or desogestrel with 30 g ethinyloestradiol. With all second-generation OCs as the reference, the odds ratios for VTE were 3.49 (1.21-10.12) for desogestrel plus 20 g ethinyloestradiol and 1.18 (0.66-2.17) for the other third-generation progestagens. INTERPRETATION: The previously reported increase in odds ratio associated with third-generation OCs when compared with second-generation products is likely to have been the result of residual confounding by age. The increased odds ratio associated with products containing 20 micrograms ethinyloestradiol and desogestrel compared with the 30 micrograms product is biologically implausible, and is likely to be the result of preferential prescribing and, thus, confounding.

venous thromboembolism

oral contraceptives

venous thromboembolism

VTE

oral contraceptives

OCs

progestagens

gestodene

desogestrel

OCs

progestagens

VTE

OC

deep-vein thrombosis

venous thrombosis

VTE

VTE

OC

VTE

OC

OCs

OC

VTE

progestagen

OCs

VTE

OCs

deep-vein thrombosis

thrombosis

venous thrombosis

VTE

OC

OCs

VTE

OCs

VTE

OCs

progestagens

VTE

desogestrel

ethinyloestradiol

gestodene

desogestrel

ethinyloestradiol

OCs

VTE

desogestrel

ethinyloestradiol

progestagens

OCs

ethinyloestradiol

desogestrel


MK-801 augments pilocarpine-induced electrographic seizure but protects against brain damage in rats.

1. The authors examined the anticonvulsant effects of MK-801 on the pilocarpine-induced seizure model. Intraperitoneal injection of pilocarpine (400 mg/kg) induced tonic and clonic seizure. Scopolamine (10 mg/kg) and pentobarbital (5 mg/kg) prevented development of pilocarpine-induced behavioral seizure but MK-801 (0.5 mg/kg) did not. 2. An electrical seizure measured with hippocampal EEG appeared in the pilocarpine-treated group. Scopolamine and pentobarbital blocked the pilocarpine-induced electrographic seizure, MK-801 treatment augmented the electrographic seizure induced by pilocarpine. 3. Brain damage was assessed by examining the hippocampus microscopically. Pilocarpine produced neuronal death in the hippocampus, which showed pyknotic changes. Pentobarbital, scopolamine and MK-801 protected the brain damage by pilocarpine, though in the MK-801-treated group, the pyramidal cells of hippocampus appeared darker than normal. In all treatments, granule cells of the dentate gyrus were not affected. 4. These results indicate that status epilepticus induced by pilocarpine is initiated by cholinergic overstimulation and propagated by glutamatergic transmission, the elevation of which may cause brain damage through an excitatory NMDA receptor-mediated mechanism.

pilocarpine

seizure

brain damage

pilocarpine

seizure

pilocarpine

tonic and clonic seizure

Scopolamine

pentobarbital

pilocarpine

seizure

seizure

pilocarpine

Scopolamine

pentobarbital

pilocarpine

seizure

seizure

pilocarpine

Brain damage

Pilocarpine

neuronal death

Pentobarbital

scopolamine

brain damage

pilocarpine

status epilepticus

pilocarpine

brain damage

NMDA


Paclitaxel, 5-fluorouracil, and folinic acid in metastatic breast cancer: BRE-26, a phase II trial.

5-Fluorouracil plus folinic acid and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) are effective salvage therapies for metastatic breast cancer patients. Paclitaxel and 5-fluorouracil have additive cytotoxicity in MCF-7 cell lines. We performed a phase II trial of paclitaxel 175 mg/m2 over 3 hours on day I followed by folinic acid 300 mg over 1 hour before 5-fluorouracil 350 mg/m2 on days 1 to 3 every 28 days (TFL) in women with metastatic breast cancer. Analysis is reported on 37 patients with a minimum of 6 months follow-up who received a total of 192 cycles of TFL: nine cycles (5%) were associated with grade 3/4 neutropenia requiring hospitalization; seven (4%) cycles in two patients required granulocyte colony-stimulating factor due to neutropenia; no patient required platelet transfusions. Grade 3/4 nonhematologic toxicities were uncommon. Among the 34 patients evaluable for response, there were three complete responses (9%) and 18 partial responses (53%) for an overall response rate of 62%. Of the 19 evaluable patients with prior doxorubicin exposure, 11 (58%) responded compared with nine of 15 (60%) without prior doxorubicin. Plasma paclitaxel concentrations were measured at the completion of paclitaxel infusion and at 24 hours in 19 patients. TFL is an active, well-tolerated regimen in metastatic breast cancer.

Paclitaxel

folinic acid

breast cancer

folinic acid

paclitaxel

Taxol

breast cancer

Paclitaxel

cytotoxicity

paclitaxel

folinic acid

breast cancer

neutropenia

granulocyte colony-stimulating factor

neutropenia

toxicities

doxorubicin

doxorubicin

paclitaxel

paclitaxel

breast cancer


Efficacy and proarrhythmia with the use of d,l-sotalol for sustained ventricular tachyarrhythmias.

This study prospectively evaluated the clinical efficacy, the incidence of torsades de pointes, and the presumable risk factors for torsades de pointes in patients treated with d,l-sotalol for sustained ventricular tachyarrhythmias. Eighty-one consecutive patients (54 with coronary artery disease, and 20 with dilated cardiomyopathy) with inducible sustained ventricular tachycardia or ventricular fibrillation received oral d,l-sotalol to prevent induction of the ventricular tachyarrhythmia. During oral loading with d,l-sotalol, continuous electrocardiographic (ECG) monitoring was performed. Those patients in whom d,l-sotalol prevented induction of ventricular tachycardia or ventricular fibrillation were discharged with the drug and followed up on an outpatient basis for 21 +/- 18 months. Induction of the ventricular tachyarrhythmia was prevented by oral d,l-sotalol in 35 (43%) patients; the ventricular tachyarrhythmia remained inducible in 40 (49%) patients; and two (2.5%) patients did not tolerate even 40 mg of d,l-sotalol once daily. Four (5%) patients had from torsades de pointes during the initial oral treatment with d,l-sotalol. Neither ECG [sinus-cycle length (SCL), QT or QTc interval, or U wave] nor clinical parameters identified patients at risk for torsades de pointes. However, the oral dose of d,l-sotalol was significantly lower in patients with torsades de pointes (200 +/- 46 vs. 328 +/- 53 mg/day; p = 0.0017). Risk factors associated with the development of torsades de pointes were the appearance of an U wave (p = 0.049), female gender (p = 0.015), and significant dose-corrected changes of SCL, QT interval, and QTc interval (p < 0.05). During follow-up, seven (20%) patients had a nonfatal ventricular tachycardia recurrence, and two (6%) patients died suddenly. One female patient with stable cardiac disease had recurrent torsades de pointes after 2 years of successful treatment with d,l-sotalol. Torsades de pointes occurred early during treatment even with low doses of oral d,l-sotalol. Pronounced changes in the surface ECG (cycle length, QT, and QTc) in relation to the dose of oral d,l-sotalol might identify a subgroup of patients with an increased risk for torsades de pointes. Other ECG parameters before the application of d,l-sotalol did not identify patients at increased risk for torsades de pointes. Recurrence rates of ventricular tachyarrhythmias are high despite complete suppression of the arrhythmia during programmed stimulation. Therefore programmed electrical stimulation in the case of d,l-sotalol seems to be of limited prognostic value.

proarrhythmia

d,l-sotalol

ventricular tachyarrhythmias

torsades de pointes

torsades de pointes

d,l-sotalol

ventricular tachyarrhythmias

coronary artery disease

dilated cardiomyopathy

ventricular tachycardia

ventricular fibrillation

d,l-sotalol

ventricular tachyarrhythmia

d,l-sotalol

d,l-sotalol

ventricular tachycardia

ventricular fibrillation

ventricular tachyarrhythmia

d,l-sotalol

ventricular tachyarrhythmia

d,l-sotalol

torsades de pointes

d,l-sotalol

torsades de pointes

d,l-sotalol

torsades de pointes

torsades de pointes

ventricular tachycardia

cardiac disease

torsades de pointes

d,l-sotalol

Torsades de pointes

d,l-sotalol

d,l-sotalol

torsades de pointes

d,l-sotalol

torsades de pointes

ventricular tachyarrhythmias

arrhythmia

d,l-sotalol


Chronic hyperprolactinemia and changes in dopamine neurons.

The tuberoinfundibular dopaminergic (TIDA) system is known to inhibit prolactin (PRL) secretion. In young animals this system responds to acute elevations in serum PRL by increasing its activity. However, this responsiveness is lost in aging rats with chronically high serum PRL levels. The purpose of this study was to induce hyperprolactinemia in rats for extended periods of time and examine its effects on dopaminergic systems in the brain. Hyperprolactinemia was induced by treatment with haloperidol, a dopamine receptor antagonist, and Palkovits' microdissection technique in combination with high-performance liquid chromatography was used to measure neurotransmitter concentrations in several areas of the brain. After 6 months of hyperprolactinemia, dopamine (DA) concentrations in the median eminence (ME) increased by 84% over the control group. Nine months of hyperprolactinemia produced a 50% increase in DA concentrations in the ME over the control group. However, DA response was lost if a 9-month long haloperidol-induced hyperprolactinemia was followed by a 1 1/2 month-long extremely high increase in serum PRL levels produced by implantation of MMQ cells under the kidney capsule. There was no change in the levels of DA, norepinephrine (NE), serotonin (5-HT), or their metabolites in the arcuate nucleus (AN), medial preoptic area (MPA), caudate putamen (CP), substantia nigra (SN), and zona incerta (ZI), except for a decrease in 5-hydroxyindoleacetic acid (5-HIAA) in the AN after 6-months of hyperprolactinemia and an increase in DA concentrations in the AN after 9-months of hyperprolactinemia. These results demonstrate that hyperprolactinemia specifically affects TIDA neurons and these effects vary, depending on the duration and intensity of hyperprolactinemia. The age-related decrease in hypothalamic dopamine function may be associated with increases in PRL secretion.

hyperprolactinemia

dopamine

hyperprolactinemia

Hyperprolactinemia

haloperidol

dopamine

hyperprolactinemia

dopamine

DA

hyperprolactinemia

DA

DA

haloperidol

hyperprolactinemia

DA

norepinephrine

NE

serotonin

5-hydroxyindoleacetic acid

hyperprolactinemia

DA

hyperprolactinemia

hyperprolactinemia

hyperprolactinemia

dopamine


Treatment-related disseminated necrotizing leukoencephalopathy with characteristic contrast enhancement of the white matter.

This report describes unique contrast enhancement of the white matter on T1-weighted magnetic resonance images of two patients with disseminated necrotizing leukoencephalopathy, which developed from acute lymphoblastic leukemia treated with high-dose methotrexate. In both patients, the enhancement was more pronounced near the base of the brain than at the vertex. Necropsy of the first case revealed loss of myelination and necrosis of the white matter. Possible mechanisms causing such a leukoencephalopathy are discussed.

leukoencephalopathy

leukoencephalopathy

acute lymphoblastic leukemia

methotrexate

loss of myelination

necrosis

leukoencephalopathy


Thrombotic complications in acute promyelocytic leukemia during all-trans-retinoic acid therapy.

A case of acute renal failure, due to occlusion of renal vessels in a patient with acute promyelocytic leukemia (APL) treated with all-trans-retinoic acid (ATRA) and tranexamic acid has been described recently. We report a case of acute renal failure in an APL patient treated with ATRA alone. This case further supports the concern about thromboembolic complications associated with ATRA therapy in APL patients. The patients, a 43-year-old man, presented all the signs and symptoms of APL and was included in a treatment protocol with ATRA. After 10 days of treatment, he developed acute renal failure that was completely reversible after complete remission of APL was achieved and therapy discontinued. We conclude that ATRA is a valid therapeutic choice for patients with APL, although the procoagulant tendency is not completely corrected. Thrombotic events, however, could be avoided by using low-dose heparin.

Thrombotic

acute promyelocytic leukemia

all-trans-retinoic acid

acute renal failure

occlusion of renal vessels

acute promyelocytic leukemia

APL

all-trans-retinoic acid

ATRA

tranexamic acid

acute renal failure

APL

ATRA

thromboembolic

ATRA

APL

APL

ATRA

acute renal failure

APL

ATRA

APL

Thrombotic

heparin


Pupillary changes associated with the development of stimulant-induced mania: a case report.

A 30-year-old cocaine-dependent man who was a subject in a study evaluating the anticraving efficacy of the stimulant medication diethylpropion (DEP) became manic during his second week on the study drug. Pupillometric changes while on DEP, especially changes in the total power of pupillary oscillation, were dramatically different than those observed in the eight other study subjects who did not become manic. The large changes in total power of pupillary oscillation occurred a few days before the patient became fully manic. Such medication-associated changes in the total power of pupillary oscillation might be of utility in identifying persons at risk for manic-like adverse effects during the medical use of psychomotor stimulants or sympathomimetic agents.

mania

cocaine

diethylpropion

DEP

manic

DEP

pupillary oscillation

manic

pupillary oscillation

manic

pupillary oscillation

manic


The negative mucosal potential: separating central and peripheral effects of NSAIDs in man.

OBJECTIVE: We wanted to test whether assessment of both a central pain-related signal (chemo-somatosensory evoked potential, CSSEP) and a concomitantly recorded peripheral signal (negative mucosal potential, NMP) allows for separation of central and peripheral effects of NSAIDs. For this purpose, experimental conditions were created in which NSAIDs had previously been observed to produce effects on phasic and tonic pain by either central or peripheral mechanisms. METHODS: According to a double-blind, randomised, controlled, threefold cross-over design, 18 healthy subjects (11 males, 7 females; mean age 26 years) received either placebo, 400 mg ibuprofen, or 800 mg ibuprofen. Phasic pain was applied by means of short pulses of CO2 to the nasal mucosa (stimulus duration 500 ms, interval approximately 60 s), and tonic pain was induced in the nasal cavity by means of dry air of controlled temperature, humidity and flow rate (22 degrees C, 0% relative humidity, 145 ml.s-1). Both CSSEPs as central and NMPs as peripheral correlates of pain were obtained in response to the CO2 stimuli. Additionally, the subjects rated the intensity of both phasic and tonic pain by means of visual analogue scales. RESULTS: As described earlier, administration of ibuprofen was followed by a decrease in tonic pain but-relative to placebo-an increase in correlates of phasic pain, indicating a specific effect of ibuprofen on the interaction between the pain stimuli under these special experimental conditions. Based on the similar behaviour of CSSEP and NMP, it was concluded that the pharmacological process underlying this phenomenon was localised in the periphery. By means of the simultaneous recording of interrelated peripheral and central electrophysiologic correlates of nociception, it was possible to separate central and peripheral effects of an NSAID. The major advantage of this pain model is the possibility of obtaining peripheral pain-related activity directly using a non-invasive technique in humans.

pain

pain

ibuprofen

ibuprofen

pain

pain

pain

pain

ibuprofen

pain

pain

ibuprofen

pain

pain

pain


Acute severe depression following peri-operative ondansetron.

A 41-year-old woman with a strong history of postoperative nausea and vomiting presented for abdominal hysterectomy 3 months after a previous anaesthetic where ondansetron prophylaxis had been used. She had developed a severe acute major depression disorder almost immediately thereafter, possibly related to the use of a serotonin antagonist. Nine years before she had experienced a self-limited puerperal depressive episode. Anaesthesia with a propofol infusion and avoidance of serotonin antagonists provided a nausea-free postoperative course without exacerbation of the depression disorder.

depression

ondansetron

postoperative nausea and vomiting

ondansetron

major depression disorder

serotonin

depressive episode

propofol

serotonin

nausea

depression disorder


Hypertensive response during dobutamine stress echocardiography.

Among 3,129 dobutamine stress echocardiographic studies, a hypertensive response, defined as systolic blood pressure (BP) > or = 220 mm Hg and/or diastolic BP > or = 110 mm Hg, occurred in 30 patients (1%). Patients with this response more often had a history of hypertension and had higher resting systolic and diastolic BP before dobutamine infusion.

Hypertensive

dobutamine

dobutamine

hypertensive

hypertension

dobutamine


Continuously nebulized albuterol in severe exacerbations of asthma in adults: a case-controlled study.

A retrospective, case-controlled analysis comparing patients admitted to a medical intensive care unit with severe exacerbations of asthma who received continuously nebulized albuterol (CNA) versus intermittent albuterol (INA) treatments is reported. Forty matched pairs of patients with asthma are compared. CNA was administered for a mean of 11 +/- 10 hr. The incidence of cardiac dysrhythmias was similar between groups. Symptomatic hypokalemia did not occur. CNA patients had higher heart rates during treatment, which may reflect severity of illness. The incidence of intubation was similar. We conclude that CNA and INA demonstrated similar profiles with regard to safety, morbidity, and mortality.

albuterol

asthma

asthma

albuterol

albuterol

asthma

cardiac dysrhythmias

hypokalemia


Hyperosmolar nonketotic coma precipitated by lithium-induced nephrogenic diabetes insipidus.

A 45-year-old man, with a 10-year history of manic depression treated with lithium, was admitted with hyperosmolar, nonketotic coma. He gave a five-year history of polyuria and polydipsia, during which time urinalysis had been negative for glucose. After recovery from hyperglycaemia, he remained polyuric despite normal blood glucose concentrations; water deprivation testing indicated nephrogenic diabetes insipidus, likely to be lithium-induced. We hypothesize that when this man developed type 2 diabetes, chronic polyuria due to nephrogenic diabetes insipidus was sufficient to precipitate hyperosmolar dehydration.

Hyperosmolar nonketotic coma

lithium

nephrogenic diabetes insipidus

manic depression

lithium

hyperosmolar, nonketotic coma

polyuria

polydipsia

glucose

hyperglycaemia

polyuric

glucose

nephrogenic diabetes insipidus

lithium

type 2 diabetes

polyuria

nephrogenic diabetes insipidus

dehydration


Effects of the intracoronary infusion of cocaine on left ventricular systolic and diastolic function in humans.

BACKGROUND: In dogs, a large amount of intravenous cocaine causes a profound deterioration of left ventricular (LV) systolic function and an increase in LV end-diastolic pressure. This study was done to assess the influence of a high intracoronary cocaine concentration on LV systolic and diastolic function in humans. METHODS AND RESULTS: In 20 patients (14 men and 6 women aged 39 to 72 years) referred for cardiac catheterization for the evaluation of chest pain, we measured heart rate, systemic arterial pressure, LV pressure and its first derivative (dP/dt), and LV volumes and ejection fraction before and during the final 2 to 3 minutes of a 15-minute intracoronary infusion of saline (n=10, control subjects) or cocaine hydrochloride 1 mg/min (n=10). No variable changed with saline. With cocaine, the drug concentration in blood obtained from the coronary sinus was 3.0+/-0.4 (mean+/-SD) mg/L, similar in magnitude to the blood cocaine concentration reported in abusers dying of cocaine intoxication. Cocaine induced no significant change in heart rate, LV dP/dt (positive or negative), or LV end-diastolic volume, but it caused an increase in systolic and mean arterial pressures, LV end-diastolic pressure, and LV end-systolic volume, as well as a decrease in LV ejection fraction. CONCLUSIONS: In humans, the intracoronary infusion of cocaine sufficient in amount to achieve a high drug concentration in coronary sinus blood causes a deterioration of LV systolic and diastolic performance.

cocaine

cocaine

cocaine

chest pain

cocaine hydrochloride

cocaine

cocaine

cocaine

Cocaine

cocaine


Heparin-induced thrombocytopenia, paradoxical thromboembolism, and other side effects of heparin therapy.

Although several new anticoagulant drugs are in development, heparin remains the drug of choice for most anticoagulation needs. The clinical effects of heparin are meritorious, but side effects do exist. Important untoward effects of heparin therapy including heparin-induced thrombocytopenia, heparin-associated osteoporosis, eosinophilia, skin reactions, allergic reactions other than thrombocytopenia and alopecia will be discussed in this article.

Heparin

thrombocytopenia

thromboembolism

heparin

heparin

heparin

heparin

heparin

thrombocytopenia

heparin

osteoporosis

eosinophilia

skin reactions

allergic reactions

thrombocytopenia

alopecia


Nonopaque crystal deposition causing ureteric obstruction in patients with HIV undergoing indinavir therapy.

OBJECTIVE: We describe the unique CT features of ureteric calculi in six HIV-infected patients receiving indinavir, the most commonly used HIV protease inhibitor, which is associated with an increased incidence of urolithiasis. CONCLUSION: Ureteric obstruction caused by precipitated indinavir crystals may be difficult to diagnose with unenhanced CT. The calculi are not opaque, and secondary signs of obstruction may be absent or minimal and should be sought carefully. Images may need to be obtained using i.v. contrast material to enable diagnosis of ureteric stones or obstruction in patients with HIV infection who receive indinavir therapy.

ureteric obstruction

indinavir

ureteric calculi

HIV-infected

indinavir

urolithiasis

Ureteric obstruction

indinavir

ureteric stones or obstruction

ureteric stones

ureteric obstruction

HIV infection

indinavir


Ischemic colitis and sumatriptan use.

Sumatriptan succinate, a serotonin-1 (5-hydroxytryptamine-1) receptor agonist, is an antimigraine drug that is reported to act by selectively constricting intracranial arteries. Recently, vasopressor responses that are distinct from the cranial circulation have been demonstrated to occur in the systemic, pulmonary, and coronary circulations. Cases have been published of coronary vasospasm, myocardial ischemia, and myocardial infarction occurring after sumatriptan use. We report on the development of 8 serious cases of ischemic colitis in patients with migraine treated with sumatriptan.

Ischemic colitis

sumatriptan

Sumatriptan succinate

serotonin

coronary vasospasm

myocardial ischemia

myocardial infarction

sumatriptan

ischemic colitis

migraine

sumatriptan


Pallidotomy with the gamma knife: a positive experience.

51 patients with medically refractory Parkinson's disease underwent stereotactic posteromedial pallidotomy between August 1993 and February 1997 for treatment of bradykinesia, rigidity, and L-DOPA-induced dyskinesias. In 29 patients, the pallidotomies were performed with the Leksell Gamma Knife and in 22 they were performed with the standard radiofrequency (RF) method. Clinical assessment as well as blinded ratings of Unified Parkinson's Disease Rating Scale (UPDRS) scores were carried out pre- and postoperatively. Mean follow-up time is 20.6 months (range 6-48) and all except 4 patients have been followed more than one year. 85 percent of patients with dyskinesias were relieved of symptoms, regardless of whether the pallidotomies were performed with the Gamma Knife or radiofrequency methods. About 2/3 of the patients in both Gamma Knife and radiofrequency groups showed improvements in bradykinesia and rigidity, although when considered as a group neither the Gamma Knife nor the radiofrequency group showed statistically significant improvements in UPDRS scores. One patient in the Gamma Knife group (3.4%) developed a homonymous hemianopsia 9 months following treatment and 5 patients (27.7%) in the radiofrequency group became transiently confused postoperatively. No other complications were seen. Gamma Knife pallidotomy is as effective as radiofrequency pallidotomy in controlling certain of the symptoms of Parkinson's disease. It may be the only practical technique available in certain patients, such as those who take anticoagulants, have bleeding diatheses or serious systemic medical illnesses. It is a viable option for other patients as well.

Parkinson's disease

bradykinesia

rigidity

L-DOPA

dyskinesias

Parkinson's Disease

dyskinesias

bradykinesia

rigidity

homonymous hemianopsia

Parkinson's disease

bleeding


Neuroleptic malignant syndrome and methylphenidate.

A 1-year-old female presented with neuroleptic malignant syndrome probably caused by methylphenidate. She had defects in the supratentorial brain including the basal ganglia and the striatum (multicystic encephalomalacia) due to severe perinatal hypoxic-ischemic encephalopathy, which was considered to be a possible predisposing factor causing neuroleptic malignant syndrome. A dopaminergic blockade mechanism generally is accepted as the pathogenesis of this syndrome. However, methylphenidate is a dopamine agonist via the inhibition of uptake of dopamine, and therefore dopaminergic systems in the brainstem (mainly the midbrain) and the spinal cord were unlikely to participate in the onset of this syndrome. A relative gamma-aminobutyric acid-ergic deficiency might occur because diazepam, a gamma-aminobutyric acid-mimetic agent, was strikingly effective. This is the first reported patient with neuroleptic malignant syndrome probably caused by methylphenidate.

Neuroleptic malignant syndrome

methylphenidate

neuroleptic malignant syndrome

methylphenidate

multicystic encephalomalacia

hypoxic-ischemic encephalopathy

neuroleptic malignant syndrome

methylphenidate

dopamine

dopamine

gamma-aminobutyric acid

diazepam

gamma-aminobutyric acid

neuroleptic malignant syndrome

methylphenidate


Differential effects of 17alpha-ethinylestradiol on the neutral and acidic pathways of bile salt synthesis in the rat.

Effects of 17alpha-ethinylestradiol (EE) on the neutral and acidic biosynthetic pathways of bile salt (BS) synthesis were evaluated in rats with an intact enterohepatic circulation and in rats with long-term bile diversion to induce BS synthesis. For this purpose, bile salt pool composition, synthesis of individual BS in vivo, hepatic activities, and expression levels of cholesterol 7alpha-hydroxylase (CYP7A), and sterol 27-hydroxylase (CYP27), as well as of other enzymes involved in BS synthesis, were analyzed in rats treated with EE (5 mg/kg, 3 days) or its vehicle. BS pool size was decreased by 27% but total BS synthesis was not affected by EE in intact rats. Synthesis of cholate was reduced by 68% in EE-treated rats, while that of chenodeoxycholate was increased by 60%. The recently identified Delta22-isomer of beta-muricholate contributed for 5.4% and 18.3 % (P < 0.01) to the pool in control and EE-treated rats, respectively, but could not be detected in bile after exhaustion of the pool. A clear reduction of BS synthesis was found in bile-diverted rats treated with EE, yet biliary BS composition was only minimally affected. Activity of CYP7A was decreased by EE in both intact and bile-diverted rats, whereas the activity of the CYP27 was not affected. Hepatic mRNA levels of CYP7A were significantly reduced by EE in bile-diverted rats only; CYP27 mRNA levels were not affected by EE. In addition, mRNA levels of sterol 12alpha-hydroxylase and lithocholate 6beta-hydroxylase were increased by bile diversion and suppressed by EE. This study shows that 17alpha-ethinylestradiol (EE)-induced intrahepatic cholestasis in rats is associated with selective inhibition of the neutral pathway of bile salt (BS) synthesis. Simultaneous impairment of other enzymes in the BS biosynthetic pathways may contribute to overall effects of EE on BS synthesis.

bile salt

EE

bile salt

BS

BS

bile salt

BS

cholesterol

sterol

BS

EE

BS

BS

EE

cholate

EE

chenodeoxycholate

EE

BS

EE

BS

EE

EE

EE

sterol

EE

EE

intrahepatic cholestasis

bile salt

BS

BS

EE

BS


Glibenclamide-sensitive hypotension produced by helodermin assessed in the rat.

The effects of helodermin, a basic 35-amino acid peptide isolated from the venom of a lizard salivary gland, on arterial blood pressure and heart rate were examined in the rat, focusing on the possibility that activation of ATP sensitive K+ (K(ATP)) channels is involved in the responses. The results were also compared with those of vasoactive intestinal polypeptide (VIP). Helodermin produced hypotension in a dose-dependent manner with approximately similar potency and duration to VIP. Hypotension induced by both peptides was significantly attenuated by glibenclamide, which abolished a levcromakalim-produced decrease in arterial blood pressure. Oxyhemoglobin did not affect helodermin-induced hypotension, whereas it shortened the duration of acetylcholine (ACh)-produced hypotension. These findings suggest that helodermin-produced hypotension is partly attributable to the activation of glibenclamide-sensitive K+ channels (K(ATP) channels), which presumably exist on arterial smooth muscle cells. EDRF (endothelium-derived relaxing factor)/nitric oxide does not seem to play an important role in the peptide-produced hypotension.

Glibenclamide

hypotension

helodermin

helodermin

amino acid

ATP

K

K

ATP

Helodermin

hypotension

Hypotension

glibenclamide

levcromakalim

helodermin

hypotension

acetylcholine

ACh

hypotension

helodermin

hypotension

glibenclamide

K

K

ATP

nitric oxide

hypotension


Long-term efficacy and adverse event of nifedipine sustained-release tablets for cyclosporin A-induced hypertension in patients with psoriasis.

Thirteen psoriatic patients with hypertension during the course of cyclosporin A therapy were treated for 25 months with a calcium channel blocker, sustained-release nifedipine, to study the clinical antihypertensive effects and adverse events during treatment with both drugs. Seven of the 13 patients had exhibited a subclinical hypertensive state before cyclosporin A therapy. Both systolic and diastolic blood pressures of these 13 patients were decreased significantly after 4 weeks of nifedipine therapy, and blood pressure was maintained within the normal range thereafter for 25 months. The adverse events during combined therapy with cyclosporin A and nifedipine included an increase in blood urea nitrogen levels in 9 of the 13 patients and development of gingival hyperplasia in 2 of the 13 patients. Our findings indicate that sustained-release nifedipine is useful for hypertensive psoriatic patients under long-term treatment with cyclosporin A, but that these patients should be monitored for gingival hyperplasia.

nifedipine

cyclosporin A

hypertension

psoriasis

psoriatic

hypertension

cyclosporin A

calcium

nifedipine

hypertensive

cyclosporin A

nifedipine

cyclosporin A

nifedipine

blood urea nitrogen

gingival hyperplasia

nifedipine

hypertensive

psoriatic

cyclosporin A

gingival hyperplasia


Torsade de pointes ventricular tachycardia during low dose intermittent dobutamine treatment in a patient with dilated cardiomyopathy and congestive heart failure.

The authors describe the case of a 56-year-old woman with chronic, severe heart failure secondary to dilated cardiomyopathy and absence of significant ventricular arrhythmias who developed QT prolongation and torsade de pointes ventricular tachycardia during one cycle of intermittent low dose (2.5 mcg/kg per min) dobutamine. This report of torsade de pointes ventricular tachycardia during intermittent dobutamine supports the hypothesis that unpredictable fatal arrhythmias may occur even with low doses and in patients with no history of significant rhythm disturbances. The mechanisms of proarrhythmic effects of Dubutamine are discussed.

Torsade de pointes

ventricular tachycardia

dobutamine

dilated cardiomyopathy

congestive heart failure

heart failure

dilated cardiomyopathy

ventricular arrhythmias

QT prolongation

torsade de pointes

ventricular tachycardia

dobutamine

torsade de pointes

ventricular tachycardia

dobutamine

arrhythmias

Dubutamine


Positive skin tests in late reactions to radiographic contrast media.

In the last few years delayed reactions several hours after the injection of radiographic and contrast materials (PRC) have been described with increasing frequency. The authors report two observations on patients with delayed reactions in whom intradermoreactions (IDR) and patch tests to a series of ionic and non ionic PRC were studied. After angiography by the venous route in patient n degree 1 a biphasic reaction with an immediate reaction (dyspnea, loss of consciousness) and delayed macro-papular rash appeared, whilst patient n degree 2 developed a generalised sensation of heat, persistent pain at the site of injection immediately and a generalised macro-papular reaction after 24 hours. The skin tests revealed positive delayed reactions of 24 hours and 48 hours by IDR and patch tests to only some PRC with common chains in their structures. The positive skin tests are in favour of immunological reactions and may help in diagnosis of allergy in the patients.

contrast media

contrast materials

PRC

PRC

dyspnea

loss of consciousness

macro-papular rash

pain

PRC

allergy


Risk of transient hyperammonemic encephalopathy in cancer patients who received continuous infusion of 5-fluorouracil with the complication of dehydration and infection.

From 1986 to 1998, 29 cancer patients who had 32 episodes of transient hyperammonemic encephalopathy related to continuous infusion of 5-fluorouracil (5-FU) were identified. None of the patients had decompensated liver disease. Onset of hyperammonemic encephalopathy varied from 0.5 to 5 days (mean: 2.6 +/- 1.3 days) after the initiation of chemotherapy. Plasma ammonium level ranged from 248 to 2387 microg% (mean: 626 +/- 431 microg%). Among the 32 episodes, 26 (81%) had various degrees of azotemia, 18 (56%) occurred during bacterial infections and 14 (44%) without infection occurred during periods of dehydration. Higher plasma ammonium levels and more rapid onset of hyperammonemia were seen in 18 patients with bacterial infections (p=0.003 and 0.0006, respectively) and in nine patients receiving high daily doses (2600 or 1800 mg/m2) of 5-FU (p=0.0001 and < 0.0001, respectively). In 25 out of 32 episodes (78%), plasma ammonium levels and mental status returned to normal within 2 days after adequate management. In conclusion, hyperammonemic encephalopathy can occur in patients receiving continuous infusion of 5-FU. Azotemia, body fluid insufficiency and bacterial infections were frequently found in these patients. It is therefore important to recognize this condition in patients receiving continuous infusion of 5-FU.

hyperammonemic encephalopathy

hyperammonemic

encephalopathy

cancer

dehydration

infection

cancer

hyperammonemic encephalopathy

hyperammonemic

encephalopathy

liver disease

hyperammonemic encephalopathy

hyperammonemic

encephalopathy

ammonium

azotemia

bacterial infections

infection

dehydration

ammonium

hyperammonemia

bacterial infections

ammonium

hyperammonemic encephalopathy

hyperammonemic

encephalopathy

Azotemia

bacterial infections


The effects of quinine and 4-aminopyridine on conditioned place preference and changes in motor activity induced by morphine in rats.

1. The effects of two unselective potassium (K(+)-) channel blockers, quinine (12.5, 25 and 50 mg/kg) and 4-aminopyridine (1 and 2 mg/kg), on conditioned place preference and biphasic changes in motor activity induced by morphine (10 mg/kg) were tested in Wistar rats. Quinine is known to block voltage-, calcium- and ATP-sensitive K(+)-channels while 4-aminopyridine is known to block voltage-sensitive K(+)-channels. 2. In the counterbalanced method, quinine attenuated morphine-induced place preference, whereas 4-aminopyridine was ineffective. In the motor activity test measured with an Animex-activity meter neither of the K(+)-channel blockers affected morphine-induced hypoactivity, but both K(+)-channel blockers prevented morphine-induced secondary hyperactivity. 3. These results suggest the involvement of quinine-sensitive but not 4-aminopyridine-sensitive K(+)-channels in morphine reward. It is also suggested that the blockade of K(+)-channels sensitive to these blockers is not sufficient to prevent morphine-induced hypoactivity whereas morphine-induced hyperactivity seems to be connected to both quinine- and 4-aminopyridine-sensitive K(+)-channels.

quinine

morphine

potassium

K

quinine

morphine

Quinine

calcium

ATP

K

K

quinine

morphine

K

morphine

hypoactivity

K

morphine

hyperactivity

quinine

K

morphine

K

morphine

hypoactivity

morphine

hyperactivity

quinine

K


Nociceptin/orphanin FQ and nocistatin on learning and memory impairment induced by scopolamine in mice.

1. Nociceptin, also known as orphanin FQ, is an endogenous ligand for the orphan opioid receptor-like receptor 1 (ORL1) and involves in various functions in the central nervous system (CNS). On the other hand, nocistatin is recently isolated from the same precursor as nociceptin and blocks nociceptin-induced allodynia and hyperalgesia. 2. Although ORL1 receptors which display a high degree of sequence homology with classical opioid receptors are abundant in the hippocampus, little is known regarding their role in learning and memory. 3. The present study was designed to investigate whether nociceptin/orphanin FQ and nocistatin could modulate impairment of learning and memory induced by scopolamine, a muscarinic cholinergic receptor antagonist, using spontaneous alternation of Y-maze and step-down type passive avoidance tasks in mice. 4. While nocistatin (0.5-5.0 nmol mouse-1, i.c.v.) administered 30 min before spontaneous alternation performance or the training session of the passive avoidance task, had no effect on spontaneous alternation or passive avoidance behaviours, a lower per cent alternation and shorter median step-down latency in the retention test were obtained in nociceptin (1.5 and/or 5.0 nmol mouse-1, i.c.v.)-treated normal mice. 5. Administration of nocistatin (1.5 and/or 5.0 nmol mouse-1, i.c.v.) 30 min before spontaneous alternation performance or the training session of the passive avoidance task, attenuated the scopolamine-induced impairment of spontaneous alternation and passive avoidance behaviours. 6. These results indicated that nocistatin, a new biologically active peptide, ameliorates impairments of spontaneous alternation and passive avoidance induced by scopolamine, and suggested that these peptides play opposite roles in learning and memory.

Nociceptin

orphanin FQ

nocistatin

learning and memory impairment

learning impairment

memory impairment

scopolamine

Nociceptin

orphanin FQ

nocistatin

nociceptin

nociceptin

allodynia

hyperalgesia

nociceptin

orphanin FQ

nocistatin

impairment of learning and memory

impairment of learning

impairment of
memory

scopolamine

nocistatin

nociceptin

nocistatin

scopolamine

nocistatin

scopolamine


Meloxicam-induced liver toxicity.

We report the case of a female patient with rheumatoid arthritis who developed acute cytolytic hepatitis due to meloxicam. Recently introduced in Belgium, meloxicam is the first nonsteroidal antiinflammatory drug with selective action on the inducible form of cyclooxygenase 2. The acute cytolytic hepatitis occurred rapidly after meloxicam administration and was associated with the development of antinuclear antibodies suggesting a hypersensitivity mechanism. This first case of meloxicam related liver toxicity demonstrates the potential of this drug to induce hepatic damage.

Meloxicam

liver toxicity

rheumatoid arthritis

hepatitis

meloxicam

meloxicam

hepatitis

meloxicam

hypersensitivity

meloxicam

liver toxicity

hepatic damage


Induction of apoptosis by remoxipride metabolites in HL60 and CD34+/CD19- human bone marrow progenitor cells: potential relevance to remoxipride-induced aplastic anemia.

The antipsychotic agent, remoxipride [(S)-(-)-3-bromo-N-[(1-ethyl-2-pyrrolidinyl)methyl]-2,6-dimethoxybenz amide] has been associated with acquired aplastic anemia. We have examined the ability of remoxipride, three pyrrolidine ring metabolites and five aromatic ring metabolites of the parent compound to induce apoptosis in HL60 cells and human bone marrow progenitor (HBMP) cells. Cells were treated for 0-24 h with each compound (0-200 microM). Apoptosis was assessed by fluorescence microscopy in Hoechst 33342- and propidium iodide stained cell samples. Results were confirmed by determination of internucleosomal DNA fragmentation using gel electrophoresis for HL60 cell samples and terminal deoxynucleotidyl transferase assay in HBMP cells. The catechol and hydroquinone metabolites, NCQ436 and NCQ344, induced apoptosis in HL60 and HBMP cells in a time- and concentration dependent manner, while the phenols, NCR181, FLA873, and FLA797, and the derivatives formed by oxidation of the pyrrolidine ring, FLA838, NCM001, and NCL118, had no effect. No necrosis was observed in cells treated with NCQ436 but NCQ344 had a biphasic effect in both cell types, inducing apoptosis at lower concentrations and necrosis at higher concentrations. These data show that the catechol and hydroquinone metabolites of remoxipride have direct toxic effects in HL60 and HBMP cells, leading to apoptosis, while the phenol metabolites were inactive. Similarly, benzene-derived catechol and hydroquinone, but not phenol, induce apoptosis in HBMP cells [Moran et al., Mol. Pharmacol., 50 (1996) 610-615]. We propose that remoxipride and benzene may induce aplastic anemia via production of similar reactive metabolites and that the ability of NCQ436 and NCQ344 to induce apoptosis in HBMP cells may contribute to the mechanism underlying acquired aplastic anemia that has been associated with remoxipride.

remoxipride

remoxipride

aplastic anemia

remoxipride

aplastic anemia

remoxipride

pyrrolidine

Hoechst 33342

propidium iodide

catechol

hydroquinone

phenols

pyrrolidine

necrosis

necrosis

catechol

hydroquinone

remoxipride

phenol

benzene

catechol

hydroquinone

phenol

remoxipride

benzene

aplastic anemia

aplastic anemia

remoxipride


Synthesis and preliminary pharmacological investigations of 1-(1,2-dihydro-2-acenaphthylenyl)piperazine derivatives as potential atypical antipsychotic agents in mice.

In research towards the development of new atypical antipsychotic agents, one strategy is that the dopaminergic system can be modulated through manipulation of the serotonergic system. The synthesis and preliminary pharmacological evaluation of a series of potential atypical antipsychotic agents based on the structure of 1-(1,2-dihydro-2-acenaphthylenyl)piperazine (7) is described. Compound 7e, 5-{2-[4-(1,2-dihydro-2-acenaphthylenyl)piperazinyl]ethyl}-2,3-dihy dro-1H- indol-2-one, from this series showed significant affinities at the 5-HT1A and 5-HT2A receptors and moderate affinity at the D2 receptor. 7e exhibits a high reversal of catalepsy induced by haloperidol indicating its atypical antipsychotic nature.

catalepsy

haloperidol


Sub-chronic inhibition of nitric-oxide synthesis modifies haloperidol-induced catalepsy and the number of NADPH-diaphorase neurons in mice.

RATIONALE: NG-nitro-L-arginine (L-NOARG), an inhibitor of nitric-oxide synthase (NOS), induces catalepsy in mice. This effect undergoes rapid tolerance, showing a significant decrease after 2 days of sub-chronic L-NOARG treatment. Nitric oxide (NO) has been shown to influence dopaminergic neurotransmission in the striatum. Neuroleptic drugs such as haloperidol, which block dopamine receptors, also cause catalepsy in rodents. OBJECTIVES: To investigate the effects of subchronic L-NOARG treatment in haloperidol-induced catalepsy and the number of NOS neurons in areas related to motor control. METHODS: Male albino Swiss mice were treated sub-chronically (twice a day for 4 days) with L-NOARG (40 mg/kg i.p.) or haloperidol (1 mg/kg i.p.). Catalepsy was evaluated at the beginning and the end of the treatments. Reduced nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry was also employed to visualize NOS as an index of enzyme expression in mice brain regions related to motor control. RESULTS: L-NOARG sub-chronic administration produced tolerance of L-NOARG and of haloperidol-induced catalepsy. It also induced an increase in the number of NADPH-d-positive cells in the dorsal part of the caudate and accumbens nuclei compared with haloperidol and in the pedunculopontine tegmental nucleus compared with saline. In contrast, there was a decrease in NADPH-d neuron number in the substantia nigra, pars compacta in both haloperidol-treated and L-NOARG-treated animals. CONCLUSIONS: The results give further support to the hypothesis that NO plays a role in motor behavior control and suggest that it may take part in the synaptic changes produced by antipsychotic treatment.

nitric-oxide

haloperidol

catalepsy

NADPH

NG-nitro-L-arginine

L-NOARG

nitric-oxide

catalepsy

L-NOARG

Nitric oxide

NO

haloperidol

dopamine

catalepsy

L-NOARG

haloperidol

catalepsy

L-NOARG

haloperidol

Catalepsy

NADPH

L-NOARG

L-NOARG

haloperidol

catalepsy

NADPH

haloperidol

NADPH

haloperidol

L-NOARG

NO


Prolonged left ventricular dysfunction occurs in patients with coronary artery disease after both dobutamine and exercise induced myocardial ischaemia.

OBJECTIVE: To determine whether pharmacological stress leads to prolonged but reversible left ventricular dysfunction in patients with coronary artery disease, similar to that seen after exercise. DESIGN: A randomised crossover study of recovery time of systolic and diastolic left ventricular function after exercise and dobutamine induced ischaemia. SUBJECTS: 10 patients with stable angina, angiographically proven coronary artery disease, and normal left ventricular function. INTERVENTIONS: Treadmill exercise and dobutamine stress were performed on different days. Quantitative assessment of systolic and diastolic left ventricular function was performed using transthoracic echocardiography at baseline and at regular intervals after each test. RESULTS: Both forms of stress led to prolonged but reversible systolic and diastolic dysfunction. There was no difference in the maximum double product (p = 0.53) or ST depression (p = 0.63) with either form of stress. After exercise, ejection fraction was reduced at 15 and 30 minutes compared with baseline (mean (SEM), -5.6 (1.5)%, p < 0.05; and -6.1 (2.2)%, p < 0. 01), and at 30 and 45 minutes after dobutamine (-10.8 (1.8)% and -5. 5 (1.8)%, both p < 0.01). Regional analysis showed a reduction in the worst affected segment 15 and 30 minutes after exercise (-27.9 (7.2)% and -28.6 (5.7)%, both p < 0.01), and at 30 minutes after dobutamine (-32 (5.3)%, p < 0.01). The isovolumic relaxation period was prolonged 45 minutes after each form of stress (p < 0.05). CONCLUSIONS: In patients with coronary artery disease, dobutamine induced ischaemia results in prolonged reversible left ventricular dysfunction, presumed to be myocardial stunning, similar to that seen after exercise. Dobutamine induced ischaemia could therefore be used to study the pathophysiology of this phenomenon further in patients with coronary artery disease.

left ventricular dysfunction

coronary artery disease

dobutamine

myocardial ischaemia

left ventricular dysfunction

coronary artery disease

dobutamine

ischaemia

stable angina

coronary artery disease

dobutamine

depression

dobutamine

dobutamine

coronary artery disease

dobutamine

ischaemia

left ventricular dysfunction

myocardial stunning

Dobutamine

ischaemia

coronary artery disease