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Parasites in Bulinus senegalensis (Mollusca: Planorbidae) and their detection.
Isoelectric focusing studies on enzyme variation between populations of the snail Bulinus senegalensis revealed that parasitic infections in the snails contributed additional bands of enzyme activity, particularly in the glucose phosphate isomerase (GPI) and malate dehydrogenase (MDH) systems. The patterns due to the parasite enzymes were, in most cases, clearly distinct from those of the host and different from each other. Parasites encountered included Schistosoma haematobium, S. bovis, Paramphistomum microbothrium, another amphistome probably belonging to the group which infect amphibians, Echinostoma revolutum, another echinostome (probably Echinoparyphium sp.), strigeids, xiphidiocercariae (these were resolved into 3 distinct types by the enzyme data) and ciliate protozoa. The 7 host populations which were examined showed marked differences in both the prevalence and variety of their parasitic infections and these variations were tentatively related to environmental differences in their respective habitats and to the nature of human contact patterns. Seasonal changes in the parasite fauna were also noted and some of the implications of the parasite load on the host population are briefly mentioned.
0.819889
Alcohol dehydrogenase (ADH) in yeasts. II. NAD+-and NADP+-dependent alcohol dehydrogenases in Saccharomycopsis lipolytica.
In Sm. lipolytica one NAD+-dependent and three NADP+-dependent alcohol dehydrogenases are detectable by polyacrylamide gelelectrophoresis. The NAD+-dependent ADH (ADH I), with a molecular weight of 240,000 daltons, reacts more intensively with long-chain alcohols (octanol) than with short-chain alcohols (methanol, ethanol). The ADH I is not or only minimally subject to glucose repression. Besides the ADH I band no additional inducible NAD+-dependent ADH band is gel-electrophoretically detectable during growth of yeast cells in medium containing ethanol or paraffin. The ADH I band is very probably formed by two ADH enzymes with the same electrophoretic mobility. The NADP+-dependent alcohol dehydrogenases (ADH II--IV) react with methanol, ethanol and octanol with different intensity. In polyacrylamide gradients two bands of NADP+-dependent ADH are detectable: one with a molecular weight of 70,000 daltons and the other with 120,000 daltons. The occurrence of the three NADP+-dependent alcohol dehydrogenases is regulated by the carbon source of the medium. Sm. lipolytica shows a high tolerance against allylalcohol. Resistant mutants can be isolated only at concentrations of 1 M allylalcohol in the medium. All isolates of allylalcohol-resistant mutants show identical growth in medium containing ethanol as the wild type strain.
0.90644
B.K. virus haemagglutinin.
Among the widely applied buffered media, the HSAG (hepes-salt-albumin-gelatin) medium at pH 5.75--6.25 was found to be the most favourable for B.K. virus haemagglutinin titration. The optimum temperature was at 4 degrees C. The haemagglutinin was not affected by temperatures up to 37 degrees C, pHs between 5.5 and 9.5, and NaCl concentrations between 0.063 M and 2.56 M. When incubated at 56 degrees C, the haemagglutinin shows a time and pH dependent decline in titre. No significant time dependent titre fall occurred at 56 degrees C if NaCl molarity was varied between 1.31 and 2.56.
0.797466
An in vivo model for investigating alpha 1- and alpha 2-receptors in the CNS: studies with mianserin.
Locomotor activity in rats was reduced by intracisternal (i.cis.) injection of the selective alpha 2-agonist clonidine and increased by the i.cis. administration of the selective alpha 1-agonists phenylephrine and methoxamine. These responses to i.cis. administered clonidine, phenylephrine and methoxamine were examined in rats pretreated subcutaneously (s.c.) with various alpha-adrenoceptor antagonists believed to exhibit preference for alpha 2- or alpha 1-receptors in peripheral tissues. At a dose that eliminated the locomotor depressant effect of clonidine, the alpha 2 -antagonist yohimbine did not antagonize the locomotor stimulant effects of phenylephrine and methoxamine. Similar results were obtained in animals pretreated with another alpha 2-antagonist piperoxane. The alpha 1-antagonist prazosin abolished the increase in motor activity elicited by phenylephrine and methoxamine, but at the same dose prazosin did not offset the decrease in motor activity caused by clonidine. The alpha 1-antagonist azapetine, at a dose that inhibited the increase in motor activity elicited by phenylephrine, was without effect on the decrease in activity produced by clonidine. These findings indicate that the locomotor responses to the alpha 2-agonist clonidine and the alpha 1-agonist phenylephrine (or methoxamine) can be used for determining whether or not a particular substance acts in vivo as a selective antagonist for alpha 1- or alpha 2-receptors in the CNS. In rats pretreated s.c. with 13.5 mg/kg of mianserin, the locomotor depressant effect of clonidine and stimulant action of phenylephrine were unchanged. At 27 mg/kg s.c., mianserin antagonized the responses to both clonidine and phenylephrine. Therefore, in this in vivo model system, mianserin given systemically did not display any appreciable selectivity for blocking alpha 1- or alpha 2-receptors in the CNS.
0.801933
Bunyavirus development in arctic and Aedes aegypti mosquitoes as revealed by glucose oxidase staining and immunofluorescence.
Northway virus replication has been detected in salivary glands of wild-caught Culiseta inornata and Aedes communis mosquitoes from the western Canadian Arctic after incubation at 4 degrees C for 9 to 11 months, and after incubation at 13 degrees C for 3 to 4 months after they received virus by oral ingestion or intrathoracic injection. Aedes hexodontus supported Northway virus replication after incubation at 13 degrees C for one month after intrathoracic injection. Aedes aegypti supported Northway virus replication after incubation at 13 degrees C or 23 degrees C for 6 to 28 days following intrathoracic injection. A larval isolate of California encephalitis virus (snowshoe hare subtype) multiplied in all 3 species of arctic mosquito after incubation at 13 degrees C for 1 to 3 months after virus was administered by oral ingestion or intrathoracic injection. Virus was detected in salivary glands of Cs. inornata after 329 days incubation at 4 degrees C after intrathoracic injection. Bunyavirus antigens in salivary glands of arctic and domestic mosquitoes were detected by the glucose oxidase immunoenzyme technique somewhat less frequently than by assay for virus infectivity.
0.781501
Regulation of melanin production by Cryptococcus neoformans.
Species of Filobasidiella, the agents of cryptococcosis, produced melanin-like pigments within 4 to 48 h with diphenol, aminophenol, and diaminobenzene compounds as substrates. The rate of phenyloxidase activity was found to be regulated by glucose and nitrogen catabolite repression. Increased glucose concentration reduced pigmentation of all serotypes of Filobasidiella, whereas repression by nitrogen sources varied with the strain. Glutamine repressed the phenyloxidases of all isolates except those of serotype B, and (NH4)2SO4 repressed the phenyloxidase of all isolates except that of serotype A. Tyrosine and glycine appeared to be near optimal for phenyloxidase activity but not necessarily for growth of all strain examined. Representatives of serotype C were unique in that their phenyloxidase system was adpative in contrast to the constitutive system found in the other serotypes. No single medium was found to support pigmentation of all strains of Cryptococcus neoformans within a 72-h incubation period; false-negative reactions can occur.
0.839935
Alkaline phosphatase of basal lateral and brush border plasma membranes from intestinal epithelium.
The alkaline phosphatase present on isolated brush border and basal lateral membranes of rat duodenal epithelium were examined by means of a variety of biochemical assays and physical methods. The two alkaline phosphatases have similar pH optima of 9.6--9.8, similar substrate km's for p-nitrophenyl phosphate (PNPP) of 71 micromolar, similar responses to the inhibitors 2-mercaptoethanol, theophylline, phenylalanine, and ethylenediaminetetraacetic acid (EDTA), similar sensitivities to calcium, magnesium, zinc, sodium, and potassium, and similar insensitivities to digestion with trypsin of papain. The two enzymes also exhibit similar molecular weights on SDS-polyacrylamide gels in the range 124,000--150,000, and both enzymes show an Rf value of 0.092 on Triton X-100 polyacrylamide gels, indicating similar intrinsic charges. The Vmax of the brush border enzyme is ten times greater than that of the basal lateral enzyme, 140 mumoles/mg-h as opposed to 14 mumoles/mg-h. The differences in Vmax are a reflection of the known distribution of alkaline phosphatase in rat duodenum, there being more alkaline phosphatase activity present on the brush border than on the basal lateral surface. One other major difference was observed between the two enzymes, the stimulation of the basal lateral and not the brush border alkaline phosphatase by SDS, Triton X-100, or cholate. We conclude that the enzymes are very similar to one another and probably perform similar membrane functions.
0.883103
Pyridoxal 5'-phosphate levels in brain after treatments which impair cerebral glucose metabolism.
Pyridoxal 5'-phosphate (PLP) concentrations were measured in brains of rats to determine whether a deficiency of this coenzyme was a common feature in hepatic coma, ethanol intoxication, and in animals treated with L-dopa or with 5-hydroxytryptophan (5-HTP) alone or with inhibitors of MAO or of L-aromatic amino acid decarboxylase. These treatments have been shown previously to be associated with reduced conversion of glucose to amino acids in brain. Cerebral PLP concentrations were reduced after some of these treatments, notably injection of ethanol, or L-dopa alone or with beta-phenylisopropylhydrazine, an inhibitor of MAO, or of 5-HTP together with N-[beta-(chlorophenoxy)ethyl]cyclopropylamine hydrochloride, Lilly 51641, another MAO inhibitor. However, in other circumstances where inhibition of conversion of glucose to amino acids has been shown (treatment with 5-HTP, or with Lilly 51641 or with [N-(D,L-seryl)-N'-2,3,4-trihydroxybenzyl]hydrazine, an inhibitor of L-aromatic amino acid decarboxylase, together with L-dopa or with 5-HTP), PLP levels in brain were unchanged, or were increased (in hepatectomized rats).
0.859158
A comparison of the non-specific acid phosphomonoesterase activity in the larva of Phocanema decipiens (Nematoda) with that of the muscle of its host the codfish (Gadus morhua).
The non-specific phosphomonoesterase (enzyme I) extracted from the larva of the codworm (Phocanema decipiens) is different from the enzyme (enzyme II) from the muscle of its host, the codfish (Gadus morhua). The pH optima were 4.0 and 4.5, and the KM values for p-nitrophenyl phosphate hydrolysis were 1.8 mM and 6.5 mM for enzymes I and II respectively. The specific specific activity in units (0.01 mumol/min) per mg protein was 4.80 +/- 0.85 and 0.54 +/- 0.07 for enzymes I and II respectively. The specific activity from uninfected muscles was only 0.39 (SD +/- 0.017) units per mg of protein. Both enzymes were inhibited by NaF, HgCl2, and cysteine but were stimulated by 2-mercaptoethanol. EDTA and iodoacetamide had no effect on enzyme I but enzyme II was activated by EDTA and inhibited by iodoacetamide. Cadmium ions inhibited both the enzymes but a conspicuous feature with enzyme II was in the increase in percentage inhibition by lowering the concentration of CD2+.
0.911199
Pathogenicity of ureaplasmas for animals and man.
Since their original isolation from the genital tract of man, ureaplasmas, previously termed T-strain mycoplasmas, have been isolated from a variety of animal species. Under experimental conditions they have been shown to cause mastitis in cattle, goats and mice, and observations made on naturally-occurring bovine pneumonia, as well as the results of experimental inoculation, suggest that ureaplasmas are responsible for a portion of bovine cuffing pneumonia. Ureaplasmas have been isolated from the genital tract of a wide variety of animals and have the potential for causing disease in this anatomical area, as the results of experimental intra-urethral inoculation of goats, for example, indicate. However, there are no data, as yet, to incriminate ureaplasmas as a cause of naturally-occurring genital tract disease nor as a cause of infertility, the latter being an area in which the results of studies are often conflicting and difficult to interpret. In man, the rôle of ureaplasmas in genito-urinary disease has been a bone of contention for many years. Experimentally, ureaplasmas produce bladder calculi in rats but so far there is no evidence that they do so in man. Further, there are no convincing data to support the notion that infertile couples possessing ureaplasmas should be treated with tetracyclines. There is an undoubted association between spontaneous abortion and low birth-weight on the one hand and the presence of ureaplasmas in the mother, abortus or infant on the other. However, evidence that the organisms cause abortion is lacking and whether they are directly responsible for low birth-weight is unknown. The association between chorioamnionitis and ureaplasma isolation is provocative enough to stimulate further work. In the case of non-gonococcal urethritis, the weight of evidence suggests that ureaplasmas cause the disease in some men. This is based on quantitative isolation, volunteer inoculation, as well as treatment studies including the use of antibiotics, such as rifampicin, which differentiate between chlamydiae and ureaplasmas.
0.846847
Structural changes of Toxoplasma gondii bradyzoites and cysts following therapy with sulfamethoxypyrazine-pyrimethamine: studies by light and electron microscopy. Consequences for chemotherapy.
Mastomys natalensis chronically infected with Toxoplasma gondii strain ALT over two months were treated with sulfamethoxypyrazine-pyrimethamine for 10 and 25 days. 72 hours after discontinuation of therapy the animals were sacrificed. The brains were removed and, following corresponding preparation, studied for the presence of the parasite and structural changes of cysts by light and transmission electron microscopy. More or less pronounced structural changes could be found in cyst walls, bradyzoites, and in particular in the endodyogeny stages. The degree of damage proved to be proportional to the intensity of the bradyzoite metabolism. The combination of drugs used was capable of passing the cyst membrane as long as the bradyzoites maintained their metabolism irrespective of its intensity. In cysts with a largely dormant metabolism that had been subject to therapy, no micromorphological differences of the ultrastructure could be recognized when compared with untreated controls of identical age; these cysts could not be influenced by treatment.
0.916786
Flunitrazepam versus placebo premedication for minor surgery.
The clinical effects of oral flunitrazepam (2 mg on the night before operation followed by 2 mg on the morning of operation) and placebo as premedicants were tested in a double-blind study in 81 gynaecological patients. The separate or total concentrations of flunitrazepam and its demethylated metabolite in plasma (measured by gas chromatography) were correlated with the clinical effects of flunitrapam premedication, assessed both sugjectively and objectively. In most parameters tested (sleep on the night before operation, sedation, apprehension, headache, pulse rate), there was a positive, significant difference between the flunitrazepam group (n = 44) and the placebo group (n = 37). No significant difference was found between the two groups in emetic effect, excitement, systolic blood pressure increase, and vene-puncture, but the patients receiving flunitrazepam felt significantly more dizziness. The temperature of the left forefinger before, during and after the anaesthesia did not vary significantly between the two groups. There was no correlation between the plasma concentration of flunitrazepam and its demethylated metabolite (separate or total concentrations) and any of the parameters tested before induction of anaesthesia. Flunitrazepam is a new oral premedicant with prominent sedative and anxiolytic actions. When the drug is given as a sedative on the night before operation, followed by a second dose on the morning of operation, the beneficial effects last for at least 8 hours after the second dose.
0.868112
Slow-release metoprolol in angina pectoris. A comparative study of a cardioselective beta-blocking drug, metoprolol, in ordinary and slow-release tablets (Durules) in the treatment of angina pectoris.
A double-blind cross-over study was undertaken to compare the effects of ordinary metoprolol tablets (tablets) 0.1 g b.i.d. and metoprolol slow-release tablets (Durules) 0.2 g once daily in 16 patients with angina pectoris. Initially, the patients were treated with placebo for 2 weeks, and then during the cross-over periods with either 1 tablet morning and evening or 1 Durules in the morning and 1 placebo in the evening. Standardized bicycle ergometer exercise tests with heart rate and blood pressure measurements were performed 2 hours after placebo, 2 hours after tablets and Durules, 12 hours after tablets and 24 hours after Durules. The patients kept diaries of their anginal attacks throughout the study. There were no statistically significant differences in total work between tablets and Durules when the values at 12 hours and 24 hours were compared. However, total work was significantly greater at 2 hours and at 12 hours after tablets and 24 hours after Durules than after placebo. Heart rate and systolic blood pressure during exercise were significantly decreased 24 hours after Durules compared to placebo. The heart rate was, however, lower 12 hours after tablets than 24 hours after Durules (p less than 0.05), although this slight difference in the degree of beta-blockade did not seem to be of clinical importance in these patients.
0.898791
Mannose-sensitive interaction of Escherichia coli with human peripheral leukocytes in vitro.
The ability of Escherichia coli which possess or lack mannose-sensitive adherence factors (adhesins) to associate with human peripheral leukocytes in vitro in the absence of serum was studied. E. coli 19+, which have mannose-sensitive adhesins, were derived from E. coli strain 19 by culturing in static Trypticase soy broth at 37 degrees C. E. coli 19-, which lack mannose-sensitive adhesins, were derived from E. coli 19 by culturing in agitated Trypticase soy broth at 30 degrees C. E. coli 19+ attached to leukocytes and stimulated the release of lysozyme but not beta-glucuronidase or lactate dehydrogenase. In contrast, E. coli 19- showed poor attachment to the leukocytes and failed to stimulate lysosomal enzyme release. During a 60-min incubation with the leukocytes, the number of viable 19+ organisms decreased, whereas the number of viable 19- remained constant. Purified type 1 pili from E. coli 19+ agglutinated the leukocytes but did not stimulate lysosomal enzyme release. Pretreatment of leukocytes with type 1 pili failed to prevent the adherence of E. coli 19+. The association of 19+ with leukocytes and subsequent release of lysozyme could be blocked by alpha-methyl-D-mannoside but not by equivalent concentrations of dextrose and sucrose. These results show that mannose-sensitive adhesins on E. coli mediate association of the organisms with leukocytes in the absence of serum components. The identity of the adhesins involved in leukocyte association has yet to be determined.
0.86883
Analysis of therapeutic and commonly abused drugs in serum and urine by gas-liquid chromatography using a photoionization detector.
A simple, rapid and sensitive gas chromatographic procedure using the photoionization detector (PID) was developed for the detection and quantitation of several drugs in serum and urine. In order to evaluate the performance of the PID, the results were compared with those of the flame-ionization detector (FID). The data indicate that the PID is 8-16 times more sensitive than the FID for the drugs studied in the barbiturate group. Excellent reproducibility was found for samples quantitated with the PID on a routine basis. The PID and FID produced statistically similar results on extracted serum samples. The correlation coefficient was 0.99. The PID also produced chromatograms with less background than those obtained with the FID for many extracted serum samples. The advantages of the PID for drug analysis in biological fluids include simplicity of operation, lack of solvent response, universal drug response, non-destructive character and stability.
0.874576
Transgastric highly selective vagotomy (HSTRV) without drainage. Preliminary report of a new simplified procedure of treatment of duodenal ulcer.
The technique of preserving the antral vagal nerve supply of the stomach and division of the gastric branches of the nerves of Latarjet is common to both operations, but by replacing the transection of the hiatal cardioesophageal vagus nerve branches (including the nerve branches accompanying the arteries entering the fundus of the stomach) with a transgastric intramural transection and excision of all nerve fibers entering the fundus, a highly selective vagotomy is achieved. Completeness of HSTRV is controlled intraoperatively by a gastric pH meter and by measuring the oxygen tension of the gastric mucosa. One year to 18 months after application of HSTRV in 74 patients with uncomplicated duodenal ulcers, mortality was nil, morbidity insignificant, the previous ulcer symptoms no longer present, and dumping syndrome, recurrence and other significant complications were not observed.
0.877857
Alcohol-induced switching over of metabolic flux in Streptomyces noursei JA0 3890b.
Short-chain alcohols, benzyl alcohol and Tween 20 were found capable of switching over the metabolic flux in Streptomyces noursei JA 3890b from the preference of oxidative deamination of alanine towards the reinforced acquisition of NH4+. These changes were correlated to the decrease of the ratio of saturated to olefinic fatty acids in the mycelium, suggesting that alcohols and other polar lipophilic compounds can interfere with the biosynthesis and the function of the cytoplasmic membrane in Streptomyces.
0.880096
[The distribution of minimal inhibitory concentrations of recently introduced cephalosporins in multiresistant strains of Escherichia coli, Proteus mirabilis and Klebsiella spec. as revealed by zone sizes of a standardized agar diffusion test (author's transl)].
Strains of a species were divided into two groups according to the number of resistances (less than or equal to 4, greater than or equal to 5) using 10 standard chemotherapeutics regularly examined, the new cephalosporins not being among them. These groups of less than or equal to 4- and greater than or equal to 5-fold resistant strains were compared for each cephalosporin tested (Fig. 1). The most different distributions of zone diameters (of both groups) were seen in Cephalothin, whereas in Cefoxitin and - with little limitations - also in Cefuroxime in the main these distributions did not differ; they covered the same field. The distributions of Cefaclor and Cefamandole took an intermediate position. With respect to the two groups similar observations were made for E. coli, proteus mirabilis and Klebsiella spec. The differences between the two groups were most marked in Klebsiella strains. E. coli exhibited the smallest differences (Fig 1). On the assumption that the distribution of zone diameters reflect that of MIC's it can be concluded that nearly all of the Cefaclor- and Cefamandole-sensitive multiresistant strains have more elevated MIC's than those with only less than or equal to 4 resistances. On the other hand it must not be expected that MIC'S OF Cefoxitin and Cefuroxim are rising in multiresistant strains. It could be demonstrated that the different qualities of the recently introduced cephalosporins revealed in multiresistant strains can be explained by different dependences on mechanisms of Cephalothin-resistance (Fig. 2). This resistance is much more frequent in greater than or equal to 5-fold resistant strains. Recommendations for clinical use derived from these results are discussed.
0.883532
Pharmacological evidence on the specialization of CNS mechanisms responsible for motor act inhibition by aversive events.
Our use of selected pharmacological agents has now extended the range of treatment-behaviour interactions previously studied by other (e.g., lesion) approaches in the search for appropriate models of behaviour organization and underlying physiological mechanisms. The case of muscarinic blockers has special interest, because the drugs induce only one type of primary change. At present, it appears difficult to reconcile the evidence in favour of a motor (perseverative) deficit with other evidence favouring an impairment of sensory processes. However, critical experiments using several go-no go avoidance tasks show that the two deficits may be inseparable. The complex profile of cue-dependent disinhibitory effects of antimuscarinics suggests that separate sensori-motor mechanisms are employed for response suppression not simply as a function of cue type, response type, or response-reinforcement relation but as a joint function of all these factors. Sedative-tranquillizing agents with so-called anti-conflict properties add still another dimension to the problem of motor act inhibition. These agents are maximally effective in disrupting response withholding when both reward and punishment follow the emission of a particular response, less consistently effective in tests with CS paired with non-contingent shock (CER), and mostly ineffective in those go-no go avoidance tasks which show a very high sensitivity to muscarinic blockade.
0.852377
[Beta-glucuronidase activity in the gastric juice and gastric mucosa of rats subjected to protein deficiency].
The experiment was performed in order to evaluate the beta-glucuronidase activity in gastric juice and gastric mucosa of rats submitted to protein-free diet. A group of 36 young adult male wistar rats was fed a protein-free diet ad libitum for five weeks; a second group of 36 wistar rats ingested a purified isocaloric 12,5% casein diet for the same period. The concentration of proteins in plasma, gastric juice and gastric glandular mucosa and the beta-glucuronidase activity in the gastric juice and gastric glandular mucosa were determined. Protein deficient rats had lower plasma protein concentration and also a lower protein concentration in gastric juice and gastric mucosa. In these animals there was no significant change of beta-glucuronidase activity in the gastric juice, but there was a significant increase of the specific enzimatic activity in the gastric mucosa. The results suggest that protein restriction in young adult rats affects the gastric mucosa. The increase of the specific beta-glucuronidase activity might be due to heightened local catabolism or to a comparatively more severe protein depletion.
0.943146
[Classification of the antidepressants (author's transl)].
The antidepressants can be classified chemically. The standard division is between the tricyclic antidepressants and the chemically heterogeneous MAOIs. Many other compounds can be included among the antidepressants, e.g. the bicyclics and possibly also the beta-stimulants, the alpha-blockers and ions such as rubidium. As regards the mechanisms of action, we have the antidepressants which act selectively upon serotonin and those which act more particularly upon noradrenaline. This notion must be extended. Dopamine may be involved in certain depressive syndromes and also other systems may have a role, such as electrolyte systems, cell permeability and the multiple influences which have a bearing upon the monoamines. Finally, the effect upon receptors and their nature are discussed. A third type of classification refers to the therapeutic spectrum of the drug. We have the sedative antidepressants, active in agitated depression and the stimulant antidepressants which are active in retarded depression. However, the two categories of antidepressants have the same global antidepressant action.
0.84271
Arginine-induced hypophosphatemia and hyperkaliemia in man.
The effects of a 0.5 g/kg body weight arginine infusion on plasma inorganic phosphates and potassium were examined in nineteen normal subjects. Plasma phosphorus displayed a highly significant (p less than 0.001) fall with a maximum depression below baseline of 1.11 +/- 0.15 mg/100 ml or 33 +/- 3% (mean +/- SEM); there was a significant correlation (p less than 0.01) between this fall and the insulin peaks induced by arginine. Plasma potassium levels displayed a distinct and significant increase in eleven of the twelve subjects studied; the maximum increase above baseline was 1.02 +/- 0.14 mEq/1 or 27 +/- 4.5% (p less than 0.001). No change occurred in blood pH values determined in four subjects. In six normal subjects, the test was repeated with the addition of somatostatin (250 micrograms bolus, followed by 500 micrograms/hr), which abolished the insulin and growth hormone response to arginine. It also abolished the fall in plasma phosphorus but appeared (if anything) to augment the increase in potassium. These findings show that arginine is responsible for a fall in plasma phosphorus related to the insulin response, and for an increase in plasma potassium of clinical significance, the mechanism(s) of which, however, are still obscure.
0.844041
Differing effects of acid versus neutral phosphate therapy of hypercalciuria.
Studies were performed on 12 patients with idiopathic hypercalciuria to evaluate the hypothesis that the acid load accompanying potassium acid phosphate would adversely affect renal calcium reabsorption and citrate excretion compared to the neutral form of the phosphate salt. During acute clearance studies, neutral phosphate (NP) led to a fall in FECa (2.2 +/- 0.6% to 0.8 +/- 0.1%, P less than 0.02) and no change in titratable acidity (TA) or net acid excretion (NAE). Acid phosphate (AP) did not reduce FECa acutely, and led to a rise in TA (22 +/- 4 to 62 +/- 6 muEq/min, P less than 0.02) and NAE (46 +/- 6 to 6 89 +/- 7 muEq/min, P less than 0.02). During chronic administration, AP resulted in higher urinary calcium excretion in both absorptive (187 +/- 29 vs. 141 +/- 18 mg/day, P less than 0.02) and renal hypercalciuric patients (233 +/- 24 vs. 173 +/- 190.02 mg/day, P less than 0.02). Also, TA and NAE were higher following AP, whereas citrate excretion was lower (375.4 +/- 64.6 vs. 633.4 +/- 28.8 mg/day, P less than 0.01). These data suggest that the reported ineffectiveness of AP in the therapy of nephrolithiasis may be related to the deleterious effects of the acid load on calcium and citrate metabolism.
0.895324
Immunochemical characterization of surface antigens of Bacteroides melaninogenicus.
Major surface antigens of Bactmbrane complex by gentle methods, purified, and characterized immunochemically. A lipopolysaccharide (LPS) was found to be chemically distinct from the LPS of facultative gram-negative bacteria in that it lacked two core sugars, 2-keto-3-deoxyoctonate and heptose, as well as beta-hydroxymyristic acid, the predominant fatty acid in the lipid A moiety. The LPS was further atypical in that it had a very low level of biologic activity. A capsular polysaccharide was demonstrated morphologically by electron microscopy with ruthenium red staining and a ferritin-labeled antibody technique. This antigen was shown to be subspecies-specific by indirect immunofluorescence. Antibody to the capsular polysaccharide was measured by an enzyme-linked immunospecific assay. The presence of a relatively impotent LPS and a surface capsular antigen may partly explain the rarity of bacteremia and septic shock due to B. melaninogenicus subspecies asaccharolyticus and the common association of this organism with abscess formation.
0.778063
Ecological studies on Azotobacter in Egyptian soils.
The present survey includes 156 representative soil samples. Results obtained confirm the richness of Egyptian soils, particularly the Nile Valley soils, in Azotobacter (60% of the samples contained greater than 10(3) colonies/g soil). Colony counts were lower than MPN estimations. Glucose is recommended for use in plating medium. Among the environmental factors affecting Azotobacter densities in soils of Egypt are: organic carbon content, total soluble salt content, pH and type of the soil, depth, cultivation, and standing crop. Pot experiments performed indicated that high incubation temperature (30, 37 degrees C) markedly enhanced development of Azotobacter as well as the gains of total nitrogen, particularly when soils are amended with 1% maize straw and incubated for 12 months. A. chrococcum was the most prevalent speciee; A. vinelandii was encountered as well. The analysis of some samples, representing soils of near Middle Eastern as well as North African countries, indicated the common occurrence of Azotobacter in these soils. Beijerinckia could not be detected in any of Egyptian or non-Egyptian samples examined.
0.910881
Neisseriaceae, a group of bacteria with dihydrofolate reductases, moderately susceptible to trimethoprim.
Dihydrofolate reductases of five species of the family Neisseriaceae were compared by means of inhibition profiles, using several structurally different inhibitors, including trimethoprim (TMP) and pyrimethamine. All enzymes were seen to be highly susceptible to the folate analog aminopterin, but exhibited moderate susceptibility to all other inhibitors tested. Approximately 200-fold higher concentrations of TMP were needed to inhibit neisserial reductases as compared to the E. coli enzyme. Besides poor penetration this is assumed to be the main basis for the low susceptibility of neisseriae to TMP. In addition to TMP all other inhibitors were also moderately active or inactive in vitro. The enzymatic differences, as seen from inhibition profiles, were statistically significant but small among all species of the genus Neisseria. Branhamella catarrhalis on the other hand was seen to be far less related to the other neisseriae, as seen by the inhibition profile of its reductase, its dihydrofolate reductase conttent, as well as by its in vitro properties.
0.874085
[Transmission of toxoplasma oocysts from domestic cats to rabbits (author's transl)].
The importance of the role of toxoplasma oocysts in the mode of spread of the infection for men and animal has differently been estimated. In own earlier experiments, we found out that the transmission of the infection by means of oocysts from cat to cat is not the rule. In a similar experimental setup, we tested now whether rabbits can be infected by getting into contact with faeces of cats containing sporulated toxoplasma oocysts (see table 1). 8 toxoplasma-free rabbits and two toxoplasma-free cats as control were placed on infectious faeces of 10 cats (group 1-8). As further controls served four non-infected rabbits being kept in the same cage (group 11-12). Four of eight rabbits which had been placed on the infectious faeces and one control animal having had no intended contact with those faeces got infected. Our experiments show that the question whether domestic cats have any significance as source of infection with toxoplasms cannot generally be answered. It has to be differentiated each time which mammal gets into contact with oocysts.
0.909612
Apoptosis. Its nature and implications for dermatopathology.
Apoptosis is a distinctive mode of cell death with characteristic morphologic features which serves as a balance to mitosis in regulating the size of animal tissues. In contrast to coagulative necrosis, the cytologic features of apoptosis suggest active self-destructive rather than progressive disintegration. It typically affects scattered individual cells which condense and bud to produce many membrane-bounded fragments in which organelles appear intact when viewed by the electron microscope. These apoptotic bodies are then phagocytosed and digested by cells resident in the tissue. Apoptosis, unlike coagulative necrosis, does not itself evoke an inflammatory response. Apoptosis is a feature of such diverse processes as deletion of phylogenetic vestiges during normal embryonic development, involution of endocrine-dependent organs after withdrawal of trophic hormones, cell-mediated immune attack on tissues, and therapeutically induced regression of neoplasms. Apoptosis has received scant attention in dermatopathology. However, it is now known to be an important feature of lichen planus, certain drug eruptions, the skin lesions of graft-versus-host reactions, the regression of plane warts, and the effects of ultraviolet damage. It is also involved in the kinetics of cutaneous neoplasms. In some of these situations, apoptotic bodies have, in the past, been given names such as Civatte bodies, colloid bodies, single-cell necrobiosis, sunburn cells, and dyskeratotic cells without their basic nature having been recognized.
0.852836
[Results of a year's mycologic and immunologic surveillance of Candida in an intensive care ward].
Patients hospitalized in an intensive care unit must be considered to be exposed to a "high risk" in terms of candida infection. They often combine several of the factors favouring the development of "candida disease": generally deficient state, multiple antibiotics, iatrogenic or pathological immune depression. While certain patients who are admitted are already suffering from "candida infestation" (endogenous localization), the possibilities of exagenous infection are numerous. This study involved 63 patients spending at least one week in the department, from September 1977 to September 1978. Mycological (pharyngeal swab, urine culture, blood culture) and immunological (hemagglutination, immunoelectrophoresis, immunofluorescence) studies were carried out routinely on admission and then every week. Amongst the 63 patients studied, 12 were admitted with negative serology, which became positive during the first 10 days. 5 already had positive serology at the time of admission. From a mycological standpoint, the pharyngeal swab was frequently positive on admission (17 times out of 63). In 63 patients, the infection was acquired during the course of the hospital stay and, in this case, positive urine cultures were more regularly associated with a positive pharyngeal culture.
0.841611
Sequestration of adenosine in crude extract from mouse liver and other tissues.
Adenosine (1 microM) was incubated in the presence of dialyzed crude tissue extract from mouse liver and its degradation determined. At high concentration of tissue extract, a fraction of adenosine was not metabolized. This phenomenon, termed sequestration of adenosine, was shown to be affected in the same way by the same factors (pH, salt, reducing agent and adenine) as those affecting the protection of adenosine against deamination in the presence of the purified cyclic AMP-adenosine binding protein/S-adenosylhomocysteinase from mouse liver (Saebø, J. and Ueland, P.M. (1979) Biochim. Biophys. Acta 587, 333--340). These data point to a role of this protein in the sequestration of adenosine in crude extract. The sequestration potency in crude extract could be determined by diluting the extract in the presence of a constant amount of adenosine deaminase added to the tissue extract. Under these conditions there was linearity of adenosine not available for degradation versus the concentration of tissue extract, and a total recovery of the sequestration potency of purified binding protein added to the crude extract was observed. The tissue level of the cyclic AMP-adenosine binding protein/S-adenosylhomocysteinase in mouse liver was determined by two independent procedures based on the sequestration of adenosine and the hydrolysis of S-adenosylhomocysteine, respectively. The intracellular concentration was calculated to be 10 microM. The sequestration of adenosine in crude extract from mouse, rat, rabbit and bovine tissues was determined and showed requirements similar to those of the sequestration in mouse liver extract. The ability to sequester adenosine was high in liver and decreased in the following order: liver, kidney, adrenal cortex, brain, uterus, cardiac and skeletal muscle.
0.922259
Spontaneous labor and elective induction--a prospective randomized study. I. Effects on mother and fetus.
In a prospective randomized study spontaneous and oxytocin induced labor "for convenience" have been compared with respect to uterine activity, duration of labor, the condition of the fetus and the newborn infant. The study consists of 84 normal patients, of whom 43 were induced at full term by amniotomy and oxytocin infusion using the Cardiff Infusion System Mark II; 41 patients served as controls. No difference in maternal age, number of previous pregnancies and pelvic score one week before the day of delivery were found between the groups. The following parameters were calculated: duration of labor, uterine activity, amount of bleeding in the third stage of labor, number of early and late decelerations as well as number of episodes of bradycardia in the CTG-recordings, birth weight, Apgar score one and five minutes post-delivery and blood gases in mother and child 60 seconds after delivery. No significant differences between the two groups were found. It is concluded that there are no increased risks to mother or fetus compared to normal labor provided that there is cephalic presentation and normal pregnancy, careful selection with respect to the length of pregnancy and the condition of the cervix and that the Cardiff infusion system is used with intrauterine pressure recording and continuous fetal heart monitoring.
0.790101
Endocrinological analysis of environmental menstrual disorders.
In 139 new student nurses, a change of menstrual cycles after school entry was studied, recording their basal body temperature over more than 4 months. In some of these students, serum FSH, LH, prolactin, estradiol, and progesterone were assayed every day or every other day throughout the second cycle after entry. Forty-six out of 72 students with previously normal menstrual cycles changed the length of their cycles. In most of the cases with a change in menstrual cycle, LH seemed not to be released in adequate amounts judging by the peak of estrogen and ovulation did not occur; the lack of sufficient LH stimulation resulted in anovulatory shortened cycles, amenorrhea or prolonged ovulatory cycles, followed by delayed ovulation. Also, in these cases, corpus luteum insufficiency persisted even when the ovulation returned. Prolactin was not considered to be involved in the mechanism of environmental menstrual disorders because serum prolactin did not increase in the cases with menstrual change. It can be concluded that environmental change or stress influences LH-RH cells in the hypothalamic centers simultaneously with the stimulation of ACTH secretion, and suppresses ovulation by decreasing LH secretion, and causes the different types of menstrual disorders.
0.832663
Inherent ranges of seminal prolactin in pre- and postvasectomy subjects.
Seminal immunoreactive prolactin (i prolactin) was studied in 14 healthy subjects, ages 31 +/- 2 SEM, before and after undergoing elective vassectomy for birth control. Seminal plasma was separated within 2 hours of ejaculation, and prolactin was measured in duplicate by radioimmunoassay. The difference between the prevasectomy (mean +/- SEM 11.1 +/- 0.8 ng/ml) and postvasectomy seminal i prolactin (mean +/- 9.9 +/- 0.7 ng/ml) was statistically significant (mean +/- SEM 1.21 +/- 0.53 ng/ml, paired t-test, t = 2.36, P < 0.05). The mean prevasectomy seminal prolactin correlated with the corresponding mean postvasectomy value of the same subject (linear regression analyses, r = 0.77, P < 0.001). This study suggested that the accessory sex organs were the major source of seminal immunoreactive prolactin, and that a minor contribution might come from the in vivo presence of spermatozoa and/or testicular secretions. It also suggested that the magnitude of seminal immunoreactive prolactin was characteristic for each individual.
0.922894
Immunodepression and the course of infection of a chronic Trypanosoma brucei infection in mice.
The relationships between course of infection, antigenic variation, and immunodepression of antibody responses to heterologous antigens have been investigated in mice chronically infected with Trypanosoma brucei. T. brucei Brunel University Trypanosomiasis (BUT) 64 produces a fluctuating parasitaemia lasting about 80 days and ending fatally. It is demonstrated that recurring peaks of parasitaemia are associated with the appearance of new variant antigenic types. At 21 and 31 days of infection, IgG responses to the heterologous antigen, sheep red blood cells (SRBC), are absent and IgM responses are less than 5% of normal. When a single dose of cyclophosphamide (300 mg/Kg) was injected into mice on day 31 of infection, the parasitaemia rose sharply in an uncontrolled fashion and the treated mice died in about 10 days. Cyclophosphamide, given in this way, is known to ablate antibody production completely but temporarily. It is therefore concluded that even though infected mice make extremely poor antibody responses to heterologous antigens, they are still capable of producing sufficient antibody to control peaks of parasitaemia associated with the emergence of new variant antigenic types. The significance of these findings is discussed in relation to recurrent hypotheses of trypanosome-associated immunodepression.
0.84538
Myosin and actin containing cells in the human postnatal thymus. Ultrastructural and immunohistochemical findings in normal thymus and in myasthenia gravis.
Samples of normal human thymus of different ages (4-63 years old) were studied by immunofluorescence microscopy (using antibodies to smooth muscle myosin, to actin from the chicken gizzard, and antibodies to myosin from human striated muscle) as well as by routine electron microscopy. Thymus tissue from myasthenia gravis patients was also investigated for comparative reasons. Epithelial cells reacted with anti-smooth, but not with anti-striated muscle myosin, whereas myoid cells reacted with antibodies to striated, but not to smooth muscle myosin. Both epithelial and myoid cells displayed a strong immunoreactivity with antiactin. Corresponding to this immunoreactivity, both cell types contained bundles of thin, actin-like filaments. Myoid cells occurred in the rounded and elongated variety, and they were a normal constituent of all thymuses investigated in this study. Ultrastructurally, this non-innervated, striated muscle-like cell type possessed bundles of thin and thick filaments as well as Z lines in a rather disorganized arrangement, resembling striated muscle after denervation or various other pathologic conditions. There were no overt differences in the number and structure of myoid cells between healthy and myasthenic patients.
0.881653
[The quality of preserved blood].
The examinations of 30 blood samples each preserved with three Yugoslav different ACD-solutions were performed. The blood samples were stored at 2-6 degrees C and examinations were performed at the day of blood donation and after on the 7th, 14th and 21st day during the storage. Differences in hematocrit (well known dilution effect of the ACD-solutions used) and intensive morphological and chemical changes were found in all blood samples regardless the type of ACD-solution used. It was shown that the permanently increasing number morphologically altered erythrocytes (echinocytes and spherocytes) and the excessive release of hemoglobin and potassium from erythrocytes were occurred during the storage of blood samles. Too, there were noticed significant decrease of pH values enormous accumulation of ammoniac and other metabolic producta.
0.791941
[Evidence for a central action of CO2 ventilatory stimulus in Pekin ducks (author's transl)].
Ventilatory responses to changes in PCO2 of the blood perfusing the central nervous system were studied breath by breath by pneumotachography in Pekin ducks under transient and steady condition. 1. Transients. In conscious birds, all the arteries to the cephalic region were tied or clamped, except the right internal carotid. The blood supply via the single remaining arterial pathway was transiently replaced, for about 15 sec, by injecting 2 ml of blood previously made either normocapnic (control PCO2 = 32 Torr) or hypercapnic (test; PCO2 = 76 Torr) from a syringe thermostated at 41 degrees C, under normal oxygenation (PO2 around 110 Torr) and mean endovascular pressure (107 mm Hg). During control injections, no significant ventilatory changes were observed. In contrast, test injections provoked an early and significant 20% increase in the minute volume of ventilation. 2. Steady conditions. Using cross-perfusion between pairs of anesthetized ducks, the head of a recipient animal (R) was vascularly isolated from the trunk and perfused by a donor (D), the nervous connections with the trunk remaining intact. When giving some CO2 to breathe to D (FICO2 = 0.05) while R breathed ambient air, arterial PCO2 increased in D and in the head of R, and hyperventilation occurred in both ducks. As a consequence of this hyperventilation, PCO2 decreased in the arterial blood and the end-tidal gas of R.
0.876203
[Derivatives of 2,3,4,5,-tetrahydro-1H-pyrido-(3,2-b)azepine and 2,3,4,5-tetrahydro-1H-pyrido(2,3-b)azepine and their corresponding lactams. II. Synthesis and pharmacologic study of their psychotropic activity].
Preparation of the N-(2-diethylaminoethyl) derivatives of lactam (II) and of the N-(3-dimethylaminopropyl) derivative of lactam (XI) is described. Synthesis of the N-[4-(2-hydroxyethyl)piperazinylacetyl]- and 1-carbothiamide derivatives of azepine (I) and of the n-(chloroformyl)- and N-(carbamoyl) derivatives of azepine (XII) are also described. Some pharmacological results indicate a partial tranquilizing activity.
0.866927
[Genesis of connective matrix of Veretillum cynomorium Pall. (Cnidaria-Anthozoa). Ultrastructural and autoradiographic study (author's transl)].
Ultrastructural study of the tissues of Veretillum cynomorium shows the presence of two mesenchymatous cellular states in the mesoglea: the nongranular mesenchymatous cells and the granular mesenchymatous cells. These latter possess, besides their cytoplasmic granules, some homogeneous fibrous inclusions, very similar to the fibrous material of the mesoglea. Granules and homogeneous fibrous inclusions are also present in the cytoplasm of some ectodermic and endodermic cells. These morphological results lead us to consider that mesoglea and epithelia can be occupied by the same granular cell type. Besides this, the digestive endodermic cells are sometimes very rich in heterogeneous fibrous inclusions histochemically identified as phagosomes. An autoradiographic study indicates two possible pathways for the synthesis of the mesoglea. The first involves the endoderm which elaborates the mesoglea at a fast rate but in small amounts. The second is due to the granular cells (mesenchymatous and epithelial) which show a slow rate of synthesis leading to the formation of the homogeneous fibrous inclusions. The heterogeneous fibrous inclusions of the digestive endodermic cell support the hypothesis of the involvement of these cells in mesogleal degradation.
0.840143
[Neurohumoral transmitter mechanisms at the cellular level].
The term neurohumoral transmission designates the transfer of a nerve impulse from a presynaptic to a postsynaptic neuron by means of a humoral agent e.g. a biogenic amine, an amino acid or a peptide. This process involves several steps, i.e. biosynthesis, storage, release, receptor interaction and inactivation of the transmitter. A neuromodulator modifies, for instance the release of a transmitter by action on a presynaptic transmitter neuron. Biogenic amines may also be released from non-synaptic nerve terminals and possibly exert a modulatory effect on other neurons. The regulation of the transmitter dynamics at the enzymatic level occurs by end-product inhibition and by enzyme induction. In addition, there are regulatory mechanisms originating from autoreceptors and postsynaptic receptors which operate via feedback action. Stimulation or inhibition of receptors may lead to receptor sub- and supersensitivity respectively. Numerous neuro-psychotropic drugs used in medical practice act on the various steps of neurohumoral transmission and thereby influence the dynamics of neurotransmitters and modulators.
0.823189
Regional variability in circadian rhythmicity of intestinal digestive-absorptive functions.
The circadian rhythms of sucrase, maltase, isomaltase, trehalase, lactase, gamma-glutamyltransferase, leucylnaphthylamide hydrolyzing activity, alkaline phosphatase and monosaccharide transport were assessed in each fifth of the small intestine of the rat in order to determine if an entire enzyme or transport system population responded in a similar manner or if there were regional differences. Animals were maintained under a light-dark cycle and fed from 1400-1800, EST for 7 days. Functional activities were assessed every 4 h for 24 h, inclusively. Quantitative, and in a few instances, qualitative differences in different areas of the intestine were found for all functions. There were portions of the lactase and alkaline phosphatase populations which displayed no rhythmicity in activity. When rhythmicity was observed there were differences in the activity patterns along the intestine for all functions. Thus, the rhythm patterns obtained from homogenates of the entire small intestine are a composite of the patterns in regions of high average activity. Also, there appears to be a reasonable amount of local control of the various functions.
0.875853
Creatine kinase in serum: 6. Inhibition by endogenous polyvalent cations, and effect of chelators on the activity and stability of some assay components.
We studied the effects of some chelators on creatine kinase activity. Creatine kinase is competitively inhibited by endogenous polyvalent cations (e.g., calcium, Ki = 4.5 mmol/L); this can be reversed by adding chelators to the reagent, resulting in a mean increase in activity of 1.14-fold at 25 degrees C and 1.18-fold at 30 and 37 degrees C. Adding chelators, 5 and 10 mmol/L, to serum stored at 37, 30, 25, 4, and -20 degrees C increased isoenzyme stability in some cases, but under certain conditions decreased it, especially at higher chelator concentrations, and more so for EGTA than for EDTA. Blood sampling into tubes prepared with chelators and storage of plasma has no advantage over serum stored in the presence of chelators. The most striking effect of chelators is their protective effect on thiols in the creatine kinase reagent. In the presence of EDTA, 2 mmol/L, the reagent is stable for at least a day at 25 degrees C or a week at 4 degrees C. The poor stability of glucose-6-phosphate dehydrogenase, which is nearly independent of chelators, is the limiting factor for reagent containing EDTA. Bis-Tris, a buffer recently recommended for assay of creatine kinase activity, is a weak chelator. Imidazole acetate buffer combined with EDTA yields activities identical to those found with Bis-Tris at assay temperatures of either 25 or 30 degrees C.
0.864127
Lymphocytotoxicity and immunosuppression by organotin compounds. Suppression of graft-versus-host reactivity, blast transformation, and E-rosette formation by di-n-butyltindichloride and di-n-octyltindichloride.
Di-n-butyltindichloride (DBTC) and di-n-octyltindichloride (DOTC) represent a new group of organometallic compounds with antilymphocytic properties. In rats they induce lymphocyte depletion in thymus and thymus-dependent areas of spleen and peripheral lymph nodes without signs of myelotoxicity or a generalized toxicity. The number and viability of cells isolated from thymus and peripheral lymphoid organs was severely decreased, whereas the number and viability of bone marrow cells was not reduced. Immunosuppressive properties of DBTC and DOTC are indicated, in this study, by a severe decrease of the graft-versus-host response and the response to the T-cell mitogens phytohemagglutinin and concanavalin A. The T-cell selectivity of these compounds is discussed. In vitro DBTC and DTOC are extremely cytotoxic. Blast transformation of human as well as rat thymocytes was already inhibited at concentrations as low as 0.02 micrograms DBTC (or 0.1 micrograms DOTC) ml medium. Also the E-rosette formation was inhibited at very low drug levels. The similarity of effects upon rat and human lymphocytes suggests that DBTC and DOTC acts in the same manner in rat and man and offers the possibility of a therapeutic use of these compounds.
0.846656
Viability of some Salmonella strains in Algerian eggs.
Whole-egg and egg-white were inoculated with S. typhi murium, S. dublin, S. oranienburg and S. oslo separately and were stored at - 1 degrees C, + 4 degrees C and 26-28 degrees C. pH value was determined every day as well as the survival of the different inoculated Salmonella strains till the end of the experiment. Stored at - 1 degrees C in case of whole-egg, egg-yolk and egg-white, pH values were 7.0, 6.0 and 7.0 while the maximum values were 8.5, 8.0 and 9.0 respectively. The shortest survival period for Salmonella strains was 101 days in whole-egg, 103 days in egg-yolk and 36 days in egg-white, while the longest period was 114, 123 and 59 days respectively. The minimum pH values of whole-egg, egg-yolk and egg-white stored at + 4 degrees C were 6.5, 6.0 and 7.0 while the maximum values were 8.5, 8.5 and 10.0 respectively, 55, 66 and 30 days were the shortest survival periods for Salmonella strains inoculated in whole-egg, egg-yolk and egg-white while the maximum periods were 81, 80 and 67 days. The minimum pH values of whole-egg, egg-yolk and egg-white held at room-temperature, were 6.0, 6.0 and 7.5 while the maxima were 8.5, 8.5 and 10.0 respectively. The minimum survival period of the Salmonella strains inoculated in whole-egg, egg-yolk and egg-white was 52, 41 and 21 days, while the maximum periods were 63, 52 and 37 days respectively.
0.820692
[Neurohumoral control of the pineal gland. A model for the study of neuroendocrine integrative processes].
This article discusses the experimental evidence which suggests that the pineal gland and its innervating neurons are useful paradigms for the study of neuroendocrine integrative processes. The obtained results can be summarized as follows: 1) existence of putative receptors for various hormones (estradiol, testosterone, 5 alpha-dihydrotestosterone, progesterone, prolactin) in the mammalian pineal gland; (2) steroid metabolic pattern in the pineal gland resembling other brain areas involved in gonadotrophic regulation; (3) control of pineal estrophilic and androphilic receptors by adrenergic transmitter through beta-adrenergic receptors and at a translational level; (4) denervation supersensitivity of hormone receptors to neurotransmitter; (5) modification of neuronal activity by hormone treatment at ganglionic and preganglionic sites of action; (6) estrophilic binding sites in ganglia; (7) correlation of pineal responsiveness to hormones with activity of sympathetic nerves; (8) modification by hormones of pineal beta-adrenergic mechanisms; (9) dissociation of hormone effects on the pineal gland in those mediated or modulated by changes in afferent neuronal activity and those relatively unaffected by denervation. Collectively these data indicate that neuroendocrine, endocrine-neural and endocrine-endocrine transducing processes occur in the pinealocytes and superior cervical ganglia.
0.887756
Inhibitory effect of guanfacine, a central alpha-adrenoceptor agonist, on prolactin secretion stimulated by insulin-induced hypoglycemia.
In six normal male volunteers oral administration of an alpha-receptor agonist, guanfacine (1 mg/q.i.d. for 4 days), had no effect on PRL release induced by 5 mg metoclopramide iv. The same treatment with quanfacine in six other normal subjects significantly reduced PRL secretion stimulated by insulin-induced hypoglycemia (P less than 0.05). These results suggest that an adrenergic pathway, hypothalamic or extrahypothalamic, might be involved in the inhibitory control of PRL secretion.
0.866226
Disorders of phagocyte function: biochemical aspects.
Intensive laboratory investigation of patients with recurrent infections, and with infections with microbial species not usually considered to be pathogenic, have led to the identification of several defects in granulocyte function. The two functions of granulocytes which have received most attention in the past decade have been locomotion (especially response to chemotactic stimulation) and microbicidal activity. Defective granulocyte chemotaxis has been demonstrated in patients with clinical manifestations suggesting abnormalities related to vasoactive amines, i.e., patients with eczema and extreme IgE hyperimmunoglobulinemia. The depressed granulocyte chemotactic responsiveness found in these patients can be reproduced in vitro when histamine and beta adrenergic agents are incubated with control granulocytes. Since these compounds have been shown to increase levels of intracellular cyclic AMP in other cells, there appears to be an association between cyclic nucleotide metabolism and regulation of granulocyte locomotion. Defective granulocyte microbicidal activity is found in patients with chronic granulomatous disease and it has been shown that there is little increase in oxidative metabolism during phagocytosis by these cells. Methods for quantitating the oxidative metabolism of granulocytes and monocytes include oxygen uptake, reduction of nitroblue tetrazolium, formate oxidation, and chemiluminescence response during phagocytosis. Since products of oxygen metabolism, i.e., hydrogen peroxide, superoxide or singlet oxygen do not accumulate in granulocyte phagocytic vacuoles, intracellular microbes are not killed (except bacterial species that produce hydrogen peroxide). The biochemical basis for defective oxidative metabolism in granulocytes from patients with chronic granulomatous disease appears to be associated with abnormal nucleotide oxidase activity.
0.791734
The value of pulsus paradoxus in assessing the child with status asthmaticus.
The presence of pulsus paradoxus (PP) in 13 episodes of status asthmaticus in 12 children, ages 13 months to 15 years, was compared sequentially to a clinical score, peak expiratory flow rate (PEFR), heart rate, arterialized capillary pH, carbon dioxide pressure (PCO2), and the ratio of inspired oxygen to oxygen pressure (FIO2)/PO2) during the first 48 hours following admission. There was a significant correlation (P less than .01) between the presence of a PP (greater than or equal to 5 mm Hg) and the clinical score (r = .79), PEFR (r = .55), and heart rate (r = .49). This was particularly striking when the PP was greater than or equal to 20 mm Hg. There was no significant correlation between the mean PP and the PCO2 or FIO2/PO2 ratio. However, a mean PCO2 exceeding 40 mm Hg was associated with a highly significant (P less than .005) difference in mean PP (22.2 mm Hg) compared to the mean PP (12.2 mm Hg) when the PCO2 was below 40 mm Hg. Although the PP technique can easily be learned by physician and nursing personnel, there are potential problems. The difficulties in children are compared to those in adults. The PP is a valuable clinical tool in assessing the severity of airway obstruction in status asthmaticus. The presence of a PP, particularly greater than 20 mm Hg, is associated with moderate to severe airway obstruction. In conjunction with the overall clinical status of the patient and frequent blood gas determinations, the PP allows for better evaluation of the patient with status asthmaticus.
0.850825
Control of the uteroplacental circulation in health and disease.
The various neurohumoral and intrinsic factors that control the uteroplacental hemodynamics in health and disease and in responses to physiologic and pharmacologic stimuli have been reviewed. The following conclusions may be derived: We still need improvement in our methodology of monitoring uterine blood flow. The present methods, which have some reliability, are not easily applicable to human subjects and even in animals their use presents problems of accuracy and sensitivity with which the investigator must become familiar. The marked and progressive increase in uterine blood flow that occurs during pregnancy is caused by complex factors, some of which are hormonal and hemodynamic in nature. The increased vascularity of the pregnant uterus and the opening of the arterioles during the process of formation of the intervillous space are important factors that facilitate the increase in uterine blood flow. The increment seems to be totally derived from the increment in the cardiac output that occurs during pregnancy. There seems to be no redistribution among the regional blood flows of the body. In the anesthetized condition the blood flow to the uterus depends largely on the perfusing pressure; the critical closing pressure seems to be around the 40 mm Hg level. This linear flow-pressure relationship does not, however, apply to the unanesthetized condition. A rise or fall in the perfusing pressure in the conscious state may be accompanied by an increase or decrease in the uterine blood flow, depending on the underlying mechanisms. Factors that lead to alpha-adrenergic stimulation produce an increase in uterine vascular resistance and a decrease in flow, irrespective of the status of the perfusing pressure. beta-adrenergic stimulation may increase uterine blood flow either through their vasodilating action or through their myometrial relaxing effects. Hypertensive diseases are most often accompanied by a decrease in uterine blood flow, whereas hypoxic states may decrease the flow even though the arterial pressure may not change significantly. It is extremely risky to extrapolate from information obtained in the anesthetized animal to the unanesthetized, conscious animal. Likewise, data obtained from normotensive conditions may not hold true for the hypertensive or hypotensive states. This is of particular relevance when one is dealing with the effects of pharmacologic agents that act on the cardiovascular system. Uterine contractions, whether induced through spontaneous or oxytocin-induced labor, produce a decrease in uterine blood flow.(ABSTRACT TRUNCATED AT 400 WORDS)
0.826673
Interoceptive conditioning through repeated suppression of morphine-abstinence. II. Relapse-testing.
The reinforcing properties of etonitazene, both conditioned and unconditioned, were measured in rats that had received saline only by continuous intravenous infusion ("saline" group) and in two groups of rats that had been physically dependent on morphine to equal degrees (and presumably had developed equal degrees of tolerance to morphine): one by once daily passive intravenous injection of morphine ("injection" group) and the other by passive continuous intravenous morphine infusion at the same daily doses for approximately the same number of days ("infusion" group). Prior to passive saline and morphine administration, all rats were trained to press right- and left-sided levers for water reinforcement from 1600 to 0800 hrs to a not more than 60-40 split, and these and other measures ("baselines") were repeated after recovery from the early (acute) morphine-abstinence syndromes. Then etonitazene, 5 micrograms/ml, was substituted for water on the nonpreferred side and all measures were repeated from 1600 to 0800 hrs once every two weeks for 20 weeks (10 "relapse" tests). It was postulated that the daily cycles of morphine-abstinence and suppression of abstinence in the injection group only would generate latent interoceptively conditioned reinforcing properties of morphine because of conditioning of suppression of abstinence to the concomitant internal sensorial effects of morphine, which would persist after morphine withdrawal and be transferred to the internal effects of another opioid, etonitazene. It was found that across the first nine relapse tests, the injection group consumed significantly more etonitazene than the infusion group, while there were no significant differences in water consumption.(ABSTRACT TRUNCATED AT 250 WORDS)
0.808608
Azidomorphines: a new family of potent analgesics with low dependence capacity.
1. Structure-activity relationship studies with new semi-synthetic isomorphine derivatives revealed that substitution of an azido group in position 6 (azidomorphines) greatly increases the analgesic potency whereas tolerance and dependence liability tend to decrease. 2. Azidomorphine (6-deoxy-6-azidodihydroisomorphine) and 14-hydroxyazidomorphine (6-deoxy-6-azidodihydro-14-hydroxyisomorphine) being in animal tests 40-300 times more potent than morphine, are the most effective analgesics among the semi-synthetic morphine alkaloids. 3. As demonstrated on mice, rats and rhesus monkeys, a remarkable dissociation between the analgesic potency and physical dependence capacity was the result of the introduction of the 6-azido group into dihydroisomorphine. 4. A dichotomy between analgesic effect and tolerance and addiction liability was demonstrated with azidomorphine also in man and the new substance proved to exert significantly less untoward effects than either morphine or pentazocine. 5. Rymazolium (Probon) a new non-narcotic analgesic which strongly potentiates the analgesic and antagonizes the respiratory depressant effect of morphine alkaloids in animals proved to hinder the development of tolerance to morphine in animals and man. 6. The azidomorphine-rymazolium association was found to be less respiratory depressant than azidomorphine administered alone. In patients with chronic intractable pain, an association of azidomorphine (0.5 mg) and rymazolium (150 mg) achieved total pain relief without noticeable euphoria and none of the twelve patients showed, according to the Himmelsbach scoring system, acute abstinence syndromes after nalorphine administration.
0.87756
Serum and pituitary concentrations of prolactin and growth hormone in mice during a twenty-four hour period.
The objective of this study was to investigate changes in the secretion of prolactin (PRL) and growth hormone (GH) occurring during a 24 h period in the mouse. Adult female mice of the C57BL/St strain and male mice of the C3H/St strain, maintained on a 14 h light and 10 h dark schedule, were used. Serum and pituitary concentrations of PRL and GH were measured by radioimmunoassay in samples collected by decapitation at hourly intervals through 24 h. Serum PRL concentrations in female mice averaged higher during the daylight hours and lower at night. However, the pattern was just the opposite in males: the values were lower during the day time and higher and variable during the night. Pituitary PRL levels dropped significantly after the onset of the dark phase in mice of both sexes. Serum GH concentrations of female mice did not fluctuate significantly with the time of the day, but those of male mice displayed a distinct flux: the levels were low from 0800 h until 1500 h, began to rise in the afternoon, and remained relatively high throughout the night. Pituitary levels of GH did not change with time in mice of either sex. The data suggest the existence of daily rhythms in the secretion of PRL and GH in mice, with marked differences related to sex. In general, the changes were most pronounced for serum PRL in females and for serum GH in males.
0.900778
A/New Jersey/76 influenza vaccine trial in seronegative schoolchildren: comparison of a subunit vaccine with a whole-virus vaccine.
In the present vaccination trial, 202 seronegative schoolchildren comprising both sexes and aged 11 to 12 years were vaccinated i.m. in the upper arm with either the subunit vaccine at a dosage of 600 CCA or 200 CCA or with a whole-virus vaccine at a dosage of 200 CCA, using the double-blind procedure. Both vaccines were prepared from the strain A/New Jersey/76 (x 53a-recombinant). The vaccination was followed four weeks later by a booster injection. In tests of local and systemic reactogenicity, it was found that at both dosages the subunit vaccine caused a low frequency of minor adverse reactions. The whole-virus vaccine was marked by a significantly higher rate of adverse reactions, whether of the local or systemic variety. The whole-virus vaccine had, however, a higher immunogenicity than the subunit vaccine, and due to the relatively high rate of adverse reactions it causes, it is not recommended for the vaccination of seronegative children. Because of its low reactogenicity, the subunit vaccine can be given at higher dosage, and it is a matter for consideration whether a better antibody response might not result from two booster injections.
0.887215
Aberrant immunity behaviour of hybrid lambda imm21 phages containing the DNA of ColE1-type plasmids.
Hybrid lambda and lambda imm21 bacteriophages carrying various ColE1-type plasmids have been constructed in vitro. The lambda imm21/plasmid recombinants display aberrant immunity behaviour, giving clear plaques under conditions where the parental phages give turbid ones and being able to grow on homoimmune lysogens. lambda imm lambda/plasmid recombinants show no such unusual behaviour. Studies with hybrids of a lambda imm21 cITS phage carrying pMB9 DNA showed the operation of the plasmid's replication system to be the basic cause of the aberrant immunity behaviour. The plasmid replication system could act as a complete alternative to the phage system during vegetative phage growth. The probable reason that lambda imm21 phages show such altered phenotypes when carrying a functional plasmid replication origin, whereas lambda imm lambda and lambda imm434 (Mukai et al., 1978) phages do not, is the relative ease of titration of the phage 21 repressor to allow transcription from pR21. Various uses are considered for the altered phenotypic behaviour of lambda imm21/ColE1-type plasmid hybrids.
0.924192
[Cytochemical studies of ultrathin frozen sections of blood platelets].
Results obtained by conventional techniques and freeze-ultramicrotomie have been compared. Ultrathin frozen sections of platelets, which are fixed by glutaraldehyde, freeze-protected by polyvinyl-pyrrolidone and encapsulated in gelatin show a well preserved fine structure after staining with buffered OsO4, phosphotungstic, phosphomolybdic or ammoniummolybdic acid. The preservation of polysaccharides or mucopolysaccharides depends on a suitable fixation, that of glycogen in certain cases depends on a double fixation (glutaraldehyde and OsO4). Cytoplasmic nucleoproteins like ribosomes are visible only after drying of sections and staining with uranyl-acetate. Lipids, both membrane lipoproteins as well as lipids in the matrices of cell organelles, are well preserved. For example the zinc-iodide osmiumtetroxide reaction yields positive results in frozen sections contrary to such obtained by conventional methods. Furthermore, the extraction of altered lipids after staining with dyes like acridine orange does not take place with this method. For this reasons the freeze-ultramicrotomy seems to be an useful alternative method.
0.8866
Falls from heights.
Falls from heights are most commonly due to accidents in children and suicide, accident, and crime-related incidents in adults. Two types of injury result from falls from heights: injury resulting from direct impact and deceleration-type injury. The injuries resulting from direct impact are mostly fractures. The body position at impact is crucial. The deceleration forces immediately post-impact result primarily in visceral and internal injury, including cranial injury. There is a lack of correlation between os calcis fractures and vertebral fractures. Spinal cord injury is infrequent. Survival figures are higher than usually assumed.
0.771567
Metabolism of oestradiol by human mammary tumour 800 x g supernatants pretreated with dihydrolipoic acid.
Incubation of human mammary tumour 800 x g supernatants with [3H]oestradiol after preincubation for 10 min at 0 degrees C with 10 mM dihydrolipoic acid resulted in metabolism of oestradiol. This was noted in 12 malignant tumours, 8 of which contained measurable oestrogen receptor levels. In 2 benign tumours lacking measurable levels of receptor, dihydrolipoic acid pretreatment had no effect. This metabolism was further stimulated by pretreatment with NAD, NADP and the anti-oestrogen Tamoxifen (ICI 46,474). When incubations were carried out in an O2 atmosphere using oxygenated buffers, the effect was suppressed.
0.91111
Cellular aspects of conjunctival inflammation induced by the synergistic action of histamine and prostaglandins.
Histamine or prostaglandin (PG) E1 or E2 administered to rabbits topically alone in high doses produced conjunctival vasodilation associated with little or no edema while their mixture at lower concentrations produced conjunctival vasodilation associated with profound edema. Sections of tissues treated with the mixture of histamine and PGE1 or PGE2 showed widespread epithelial and subepithelial inflammatory cellular infiltration. Conjunctival smears from eyes treated with the histamine/PG mixture contained small lymphocytes and polymorphonuclear leukocytes, including eosinophilic and occasionally basophilic cells. Differential staining of the polymorphs demonstrated both eosinophils and pseudoeosinophils. Histological examination of the conjunctival smears and sections of the lids obtained from eyes treated with either histamine or PGE1 or PGE2 alone did not show any detectable increase of inflammatory cells when compared to normal controls. The clinical and histological results indicate that the synergistic effect of histamine with PGs of the E-type in the conjunctiva produces an inflammatory response similar to that seen in various clinical forms of human allergic conjunctivitis. Such a response could not be produced by histamine or PGE1 or PGE2 alone even at much higher doses than in the mixture. The data indicate that an interplay of several different mediators may be crucial in the conjunctival response in allergy.
0.900727
Factors affecting the measurement of classically conditioned fear in rats following exposure to escapable versus inescapable signaled shock.
Three experiments are reported in which rats first received 50 escapable or inescapable signaled-shock trials. Experiment 1 (n = 22) employed an acquired-drive paradigm and found inescapable shock subjects learned a hurdle-jump response to escape the signal less rapidly than did escapable-shock subjects. Experiment 2 (n = 24) employed a conditioned emotional response paradigm and found inescapable-shock subjects suppressed more when the signal was introduced in the appetitive bar-pressing task. Both experiments measured spontaneous activity immediately following conditioning and found no group differences. Experiment 3 (n = 39) employed the same activity task and found no difference between escapable- and inescapable-shock groups when the signal was introduced into the activity task. Both groups displayed less activity than a nonshock control group during the signal. The results suggest that lack of control over the shock in the conditioning phase did not result in an increase of conditioned fear. The results are discussed in terms of a learned active-inactive predisposition to respond.
0.886565
Does cardiac transplantation prolong life and improve its quality? An updated report.
The current status of the human cardiac transplant experience at Stanford University Medical Center is presented in order to reassess its role in the treatment of end-stage cardiac disease. Of 109 patients undergoing transplantation at Stanford between January 1968 and August 1976, 44 were still alive as of August 1, 1976. The overall 1- and 2-year survival rates for the series are 52% and 43%, respectively. Sixty-nine patients have survived more than 3 months, and their overall 1- and 2-year survival rates are 80% and 66%, respectively. Of the 3-month survivors, 62 (90%) returned to functional Class I New York Heart Association cardiac status and most of these returned to their pre-illness activities. Of 40 patients selected for transplantation for whom a donor did not become available, 38 were dead in less than 6 months. Complications related to immunosuppression with steroids are currently the major barrier to longer survival and improved rehabilitation postransplantation. On the basis of these data we conclude that cardiac transplantation not only prolongs survival, but can return carefully selected recipients to an active life.
0.862294
The role of cortical orientation in the control of the direction of ciliary beat in Paramecium.
The swimming behavior of many ciliate protozoans depends on graded changes in the direction of the ciliary effective stroke in response to depolarizing stimuli (i.e., the avoiding reaction of Paramecium). We investigated the problem of whether the directional response of cilia with a variable plane of beat is related to the polarity of the cell as a whole or to the orientation of the cortical structures themselves. To do this, we used a stock of Paramecium aurelia with part of the cortex reversed 180 degrees. We determined the relation of the orientation of the kineties (ciliary rows) to the direction of beat in these mosaic paramecia by cinemicrography of particle movements near living cells and by scanning electron microscopy of instantaneously fixed material. We found that the cilia of the inverted rows always beat in the direction opposite to that of normally oriented cilia during both forward and backward swimming. In addition, metachronal waves of ciliary coordination were present on the inverted patch, travelling in the direction opposite to those on the normal cortex. The reference point for the directional response of Paramecium cilia to stimuli thus resides within the cilia or their immediate cortical surroundings.
0.911572
Neurons of the dorsal lateral geniculate nucleus of the albino rat.
Light and electron microscopic observations were made on the dorsal lateral geniculate nucleus (DLGN) of 33 young adult male albino rats. Three variants of the Golgi silver impregnation technique were employed in the light microscopic studies. Neurons were classified into three categories based on location, dendritic pattern, and dendritic appendages. Type 1 and type 3 neurons were distributed throughout the DLGN. Type 2 neurons were located in the superficial zone. Dendritic appendages of type 1 and type 2 neurons indicated these cells may function as geniculo-cortical relay neurons. The type 3 neurons had lobulated dendritic appendages and an axon that terminated withinthe nucleus. Type 3 neurons may represent Golgi-type-II interneurons. Camera lucida drawings, photomicrographs, and electronmicrographs illustrate the characteristics ofthe three cell types. The literature on ultrastructural and neurophysiological findings may substantiate the presence of three neuronal types. Initially, the rat DLGN does not appear as elaborately organized as the nucleus observed in cats and primates; however, there are notable similarities in neuronal morphology and synaptology.
0.856578
Immunochemical staining of the rat adenohypophysis in organ culture.
Rat anterior pituitaries were cytologically studied following cultivation in organ culture, with and without the addition of hypothalamic and cortical extracts. Although five distinct cell types could be identified with classical stains in the uncultivated glands, the peroxidase-labeled antibody technique (using antibodies against STH, LTH, FSH, LH and TSH) showed that not all of the immune-specific cell types were being identified with the classical stains. This discrepancy was magnified following culture as chromophilic cells seen with classic stains decreased in number with an increase in culture time. The peroxidase technique, however, revealed that all cells remained constant in type and number regardless of time in culture. While the addition of either hypothalamic or cortical extract to the culture medium produced cytological alterations demonstrated by the classical dyes, the antibody technique showed no such alterations. Such a comparison of staining techniques emphasizes the hazards of relying solely on histological procedures to reveal the hormonal activity of the pituitary gland.
0.841051
Assessment of reactivities of natural antibodies to endogenous RNA tumor virus envelope antigens and virus-induced cell surface antigens.
The autogenous humoral immune response of mice to their endogenous leukemia virus (MuLV) has been examined with respect to the reactivities of natural antibodies to MuLV envelope antigens and virus-induced cells surface antigens. The natural reactivity of MuLV envelope antigens was evaluated by means of a radioimmune precipitation assay of intact and disrupted virus, as well as by virus neutralization tests. The specificity of natural antibody for MuLV envelope antigens was determined by immunoelectron microscopy and radioimmune precipitation. Antibody reactivity to virus-induced cell-surface antigens was evaluated by immunoelectron microscopy and a complement-dependent cytotoxicity test. The strains of mice seleced for study were C57BL/6, C3H/Anf, and the C57BL/6 X C3H/Anf F1 hybrid. Although there were quantitative differences in the antibody levels among these various strains, the naturally recognized antigenic determinants of the virus were consistent, i.e., gp68, gp-43, and p15. High levels of neutralizing antibody against the xenotropic BALB:virus-2 were detected in these various normal sera with the focus reduction assay; however, only marginal levels of neutralizing activity against Moloney leukemia virus were detected with the XC virus assay. No anticellular antibody could be detected in these normal sera with the complement-dependent cytotoxicity assay.
0.841501
Ultrastructural study of the effect of bleomycin A2 on the nucleolus and its possibly related cytoplasmic constituents in Novikoff hepatoma cells.
Treatment of Novikoff hepatoma ascites cells with bleomycin A2, in vivo as well as in vitro, in varying doses produced marked alterations in nucleolar and cytoplasmic ultrastructural organization. A series of changes occur including formation of fibrillar centers, fragmentation of fibrillar nucleolar elements, appearance of microspherules, and the loss of fibrillar elements from these nucleoli. A bleomycin concentration of 10 mug/ml in vitro produced an increased number of fibrillar centers with well-defined nucleolonemas. At a concentration of 50 mug/ml, there was an increase in number and fragmentation of these fibrillar centers and many microspherules were found throughout the nucleolus. Approximately one-fourth of the cells contained cytoplasmic fibrillar bodies and amorphous fibrous tufts around the nuclear envelope. At a bleomycin concentration of 100 mug/ml, the nucleoli contained more granular elements and numerous microspherules. Almost 90% of the cells contained cytoplasmic fibrillar bodies. The effects of bleomycin in vivo (10 mg/kg) closely resemble those found in vitro with concentrations of 50 and 100 mug/ml.
0.893818
Audiometric comparison of the middle and late components of the adult auditory evoked potentials awake and asleep.
The middle and the late components of auditory evoked potentials were alternately recorded in sequential sets from 28 adults, both awake and asleep. Sleep was induced by secobarbital and was monitored for depth. 1000 c/sec tone pips in one laboratory or filtered clicks in the other were delivered at 10, 20 or 30 dB sensation level. Control collections without stimulation were included. For the middle responses a single simple scoring template and one set of voltage criteria could be used for all stages of waking and sleeping. For late responses different templates and voltage criteria were needed. Estimates of the threshold of detection of the evoked potentials were based on the percentage of clearly positive responses was often not attained at 30 dB SL, i.e., the threshold was indeterminate. In light sleep and awake the middle responses of most subjects gave thresholds more sensitive than the late by 10-15 dB and also fewer indeterminate trials. The results in our two laboratories agreed closely in spite of differences in equipment and details of procedure. The relatively low thresholds of the middle responses (median 17.5 dB SL awake and 15 dB SL in light sleep) suggest that the middle responses must be considered seriously for use in clinical electric response audiometry, even though one of the 28 subjects failed to yield any identifiable middle responses.
0.871533
Visual evaluation and computer analysis of the EEG--a comparison.
Spectral parameter analysis (SPA) of the EEG provides a description of the distribution of spectral power in the EEG signal in the form of a rational spectrum with not more than 8 parameters. The spectrum is divided into 1-3 components described by frequency and power parameters: bandwidth (delta), peak frequency (f) and power (G). These spectral parameters are determined with the aid of a computer. The character of the EEG signal decides whether 1, 2 or 3 components (delta, alpha, beta) are needed to describe the spectrum. To test its practical value, the result of SPA was compared with that of ordinary visual evaluation of the EEG of 65 healthy men between the ages of 18 and 22 years. 20 sec sections from different leads were analysed and evaluated visually. Each EEG section was graded according to the amount of visually evaluated slow activity (VESA). To investigate the relation between the degree of VESA and the SPA result, statistical calculations (variance and regression analyses) were carried out, both for single SPA parameters and for the general type of spectrum, i.e., the number of components composing the spectrum. The SPA results from sections with artefacts were treated separately and compared statistically with results from artefact-free sections. In records with a high degree of VESA, all the leads analysed showed a tendency to have a power spectrum of low order, i.e., with few components. In most leads there was a linear regression between the degree of VESA and the bandwidth and power of the delta and alpha components. In several cases this relation was an expression of a significant linear change of the SPA parameter as a function of the degree of VESA. On the other hand the parameters of the beta component showed no relation to the degree of VESA. It was found that muscle activity could influence any spectral component thereby providing it with a strongly increased bandwidth. This is probably due to the fact that muscle activity resembles white noise in this particular frequency range. Low frequency artefacts affected only the delta component the bandwidth of which was significantly smaller than in the artefact-free sections.
0.762385
Cortico-striatal evoked potentials in the monkey (Macaca mulatta).
A systematic study has been made of topographic organization in the striatum of evoked potentials elicited by stimulation of the cerebral cortex in unanesthetized, comatose monkeys (Macaca mulatta). Stimulation of the dorsal field of the prefrontal convexity elicited potentials primarily in rostral portions of the caudate, while stimulation of the ventral field of the prefrontal convexity elicited potentials in ventromedial areas of the putamen. Stimulation of different points on the precentral and postcentral gyri revealed a distinct somatopic organization of evoked responses in the putamen, although responsive zones in the putamen to precentral and postcentral stimulation showed almost total overlap. An overlap of responsive zones to stimulation of the dorsal prefrontal convexity and the premotor area (area 6) was found in the dorsolateral part of the rostral caudate, while a zone of overlap of responses to stimulation of the ventral prefrontal convexity and "hand" motor area of the precentral gyrus was found in the ventromedial area of the putamen near the commissural level.
0.833154
Evolution of sleep spindles in childhood.
Twenty-six normal children (age range range 4-68 months) were studied during Stage 2 sleep which occurred within 20 min preceding or following the first three REM periods of the night. Sleep spindles were measured in Fp1T3. The number, length, and percent of sleep spindle activity were found to be maximal at 46 months of age. Beyond 6 months spindle activity decreased to reach minimal values by 27 months, remained fairly constant to 54 months, then rose again to higher values in the oldest subjects. The mean spindle-wave frequency was 1314 c/sec in subjects younger than 40 months, but was 12-13 c/sec in older subjects. Spindle onsets in Fp1T3 and Fp2T4 were more often concurrent in older as compared to younger subjects. Auditory stimulation (binaural clicks, 60 dB above hearing threshold) affected neither the incidence nor the length of spindles during sleep. Because sizable changes in sleep spindle activity are found between 3 months and 5 years of age, and because such changes are relatively consistent between subjects, it is concluded that sleep spindles recorded between frontal and temporal areas may serve as a useful index of neural maturation in the human subject.
0.876987
Editorial: Oral glucose/electrolyte therapy for acute diarrhoea.
Much clinical experience has been gained in the use of the glucose/electrolyte oral solutions in the treatment of acute diarrhea. Those patients who are in shock or too weak to drink need intravenous fluids to correct their total deficit. With isotonic polyelectrolyte fluids rehydration may be achieved in 2-4 hours. Subsequently, most of these patients can be given oral fluids to replace continuing stool loss. Patients who are not in shock and who are sufficiently strong to drink at the outset nearly always can be rehydrated with oral fluids alone. Vomiting is most likely caused by acidosis and volume depletion, and these can be corrected in severely dehydrated patients by intravenous therapy and by oral therapy in those not in shock and able to drink by oral therapy. Proponents of oral glucose/electrolyte therapy for diarrhea, like other proponents of new treatments, have great visions of its benefits to the world, yet these visions require validation. The biggest problem will be getting glucose and electrolytes to where they are most needed -- at the level of home and village.
0.871642
Mode of insulin action.
A unifying hypothesis is proposed for the mechanism of insulin action in adipose tissue. Insulin both induces displacement of Ca++ from a membrane-bound pool and inhibits efflux of the ion, thereby facilitating a rise in intracellular free Ca++ concentration. The former effect could enhance the transport of substrates and ions into the cell, while the latter modulates the activity of some intracellular enzymes to stimulate glycogenesis, lipogenesis, and decrease lipolysis and glycogenolysis. The calcium ion might act as the missing second messenger for insulin action.
0.821268
Core isoelectrofocusing.
An improved method of isoelectrofocusing is described. A plastic rod is centered in a tube and the lumen is filled with gel. After separation the rod is withdrawn and replaced by staining solution. Staining and destaining are quick and simple. The gel remains stabilized in the tube allowing no distortion or breakage and permitting accurate localization of separated bands.
0.804584
The antibody-enzyme analogy. Characterization of antibodies to phosphopyridoxyltyrosine derivatives.
Stable analogs of the crucial Schiff base intermediate of enzymatic and nonenzymatic pyridoxal phosphate catalysis have been used as haptens for induction of specific antibodies. N-(5-phosphopyridoxyl)-3'-amino-L-tyrosine and its conformationally distinct cyclized derivative resemble the Schiff base formed upon mixing tyrosine with pyridoxal phosphate. These compounds were covalently coupled to a protein carrier via the 3'-amino group so as to confer a prescribed orientation, with the coenzyme region farthest removed from the carrier. A third antigen, with the phosphopyridoxyl group alone as the hapten, was prepared by linkage of pyridoxal phosphate directly to free amino groups on the carrier protein. Antibodies elicited for each determinant were purified by means of appropriate affinity columns. Antibody heterogeneity was observed in that different species could be separated from a given serum by sequential elution from the affinity columns with 1 M sodium phosphate buffers of pH 7.6, 5.2, 2.6 and 1.5. In assays of quantitative precipitation, inhibition of precipitation, equilibrium dialysis, and fluorescence quenching, antibodies to the phosphopyridoxyltyrosine haptens showed specificity for the phosphorylated form of the coenzyme and binding activity for both the coenzyme and tyrosine portions of the hapten. Antibodies to the phosphopyridoxyl groups alone did not display a similar reactivity toward the tyrosine portion of the complex haptens. The cyclic and noncyclic conformations of the hapten were serologically distinct, as antibody to each reacted preferentially with the homologous form.
0.840464
Antibacterial activity of antisera against homologous and heterologous Escherichia coli of porcine origin.
Fourteen enteropathogenic and five nonenterotoxigenic Escherichia coli strains isolated from pigs were used for producing antisera in rabbits and pigs. These antisera were used in an vitro test system for antibacterial activity against homologous and heterologous porcine E. coli strains. Antibacterial titres were determined against the homologous strains and the percent reduction in CFU/ml caused by a 1/200 dilution of the sera against heterologous strains was determined. The results indicated that following immunization the antibacterial activity of serum against homologous and heterologous strains was significantly increased. This activity did not appear to be influenced by O and K antigen relationships among the organisms or by enterotoxigenicity of the vaccine strains. When antiserum produced against a combination of three enteropathogenic E. coli was tested against 20 strains a wider spectrum of heterologous antibacterial activity was obtained than with antiserum produced against any individual strain. The results indicate the existence in E. coli strains of porcine origin of common antigenic determinants not related to the serological formula and that a selected combination of strains can be expected to induce antibacterial acitivity against a wide variety of serological types of porcine enteropathogenic E. coli.
0.885597
Interaction of complex polysaccharides with the complement system: effect of calcium depletion on terminal component consumption.
Complex polysaccharides and lipopolysaccharides can activate the terminal components of complement by either the classical (antibody, C1, C4, and C2) or alternative complement pathways, but the relative importance of either pathway for terminal component consumption in normal serum is poorly understood. Since classical complement pathway function requires both calcium and magnesium ions, whereas the alternative pathway requires only magnesium ions, selective chelation of calcium ions in serum can be used to block the classical complement pathway while leaving the alternative pathway intact. In these studies, ethyleneglycol-bis-(beta-aminoethyl ether)N, N-tetraacetic acid, a potent chelator or calcium, was used to block the classical complement pathway in normal guinea pig serum. Consumption of the terminal complement components by endotoxin, inulin, and zymosan in such serum was strikingly depressed when compared to serum containing an intact classical complement pathway. These studies demonstrate that in normal serum, both the classical and alternative complement pathways participate in the consumption of the terminal complement components by complex polysaccharides and lipopolysaccharides.
0.868859
The reaction of mitochondria in the coleoptiles of rice (Oryza sativa L.) with diaminobenzidine.
Diaminobenzidine, DAB, was applied to segments of aerobically and anaerobically grown coleoptiles of rice, Oryza sativa L., with the object of studying the location of cytochrome oxidase at the electron-microscope level. A specific staining of mitochondrial cristae and inner membrane was obtained, with no reaction in other organelles; with extended periods of incubation, the reaction product filled the mitochondria completely. In anaerobically grown coleoptiles, the reaction was much slower and the difference was particularly marked in vascular bundle companion cells and parenchyma, which gave the strongest reaction in aerobic tissue, but in the anaerobic stained even less than the cortical parenchyma. The reaction was inhibited by boiling and slowed very much by lowering of the incubation temperature from 27 to 4 degrees C. This indicated the involvement of an enzymic reaction and cyanide inhibition indicated that a haem enzyme was involved. The catalase inhibitor aminotriazole did not inhibit DAB oxidation. Nevertheless the specificity of the reaction for cytochrome oxidase must be questioned, because preheating of the tissue to 60 degrees C before incubation, which would be expected to destroy cytochrome oxidase activity, failed to decrease the oxidation, at least in aerobically grown coleoptiles. It is concluded that DAB is oxidized in the rice coleoptile tissue by a cytochrome system, and the development of this system is inhibited by anaerobiosis, but the oxidation cannot be claimed to represent cytochrome oxidase activity exclusively. Perhaps other autoxidizable, more heat-stable cytochromes participate in the reaction.
0.88825
Characterization of cytotoxic effector cells in the mouse mammary tumor system.
Cell types involved in the immune response in vitro to MTV-induced BALB/cfC3H mammary tumors have been studied with techniques designed to inactivate or deplete different cytotoxic effector cells from spleen cells populations. The minimal activity of spleen cells from neonatally MTV-infected virgin BALB/cfC3H females is dependent upon the presence of T cells. Spleens from multiparous BALB/cfC3H females bearing small tumors are similar to those of tumor-free multiparous females. However, after the tumors grow to large size, the activity of the non-T cell population is no longer detectable. The cytotoxic activity of spleen cells from BALB/c females older than 14 weeks (supposedly not infected with MTV) is not dependent upon the presence of T cells. No activity is shown by spleen cells from BALB/c females younger than 14 weeks. Positive control spleen cells were obtained from C3H female mice who had been immunized to BALB/c histocompatibility antigens by a skin allograft; both a T cell and a non-T cell response were found.
0.756775
Immunologic properties of bacterial lipopolysaccharide (LPS): correlation between the mitogenic, adjuvant, and immunogenic activities.
Bacterial lipopolysaccharide (LPS) was demonstrated to have the capacity in mice to enhance the response to soluble bovine serum albumin (BSA) and to interfere with the induction of tolerance to human gamma-globulin (HGG). These adjuvant activities were shown to occur under conditions in which LPS could also function as a B cell mitogen. This positive correlation was established by utilizing two experimental situations in which LPS was non-mitogenic for spleen cells. Thus, on the one hand, it was found that LPS did not function as an adjuvant in C3H/HeJ mice, a unique strain whose spleen cells were also unresponsive to LPS-induced mitogenesis. On the other hand, in strains which did respond to LPS mitogenically, LPS failed to function as an adjuvant when it was chemically altered to reduce its in vitro mitogenic activity. A correlation was also observed between mitogenesis and the capacity of LPS to function as a specific immunogen i mice. In contrast to the sustained and prolonged plaque-forming cell response that was observed in mice whose spleen cells were also responsive to LPS-induced mitogenesis, the response was relatively transient in the C3H/HeJ strain. These results are discussed in view of the possible in vivo modes of action of LPS.
0.876591
Mechanism of action of concanavalin A on human basophils.
Concanavalin A (Con A) activates human basophils to release histamine. This reaction has great similarities to that of antigen-or anti-IgE-induced release. It is characterized by a two stage reaction: the initial stage is the binding of Con A to the cell and the second stage is a secretory process of the cell. Cells desensitized by incubation with excess amounts of Con A or by prolonged incubation in the absence of cations cannot be activated to release with antigen or anti-IgE. When the native (tetravalent) Con A molecule is modified by succinic anhydride to become divalent it is much less active in releasing histamine. There is wide variation in the response of cells from different individuals to Con A. However, a close correlation exists between the histamine release induced by Con A and anti-IgE. Therfore, in genral, cells from allergic donors release more histamine with Con A than those from non-allergic individuals. Evidence is presented to demonstrate that Con A acts by binding to carbohydrate groups on the IgE molecule located on the basophil membrane. On a molar basis, IgE is 4000-fold more active than alpha-methyl-D-mannoside in inhibiting the Con A-induced histamine release. Succinyl Con A blocks the ability of Con A and anti-IgE equally well and to a lesser extent the ability of antigen to activate cells to release histamine.
0.836261
The diisopropylfluorophosphate inhibitable step in antigen-induced histamine release from human leukocytes.
DFP inhibits early events in antigen-induced histamine release from human leukocytes. If added to cells 5 min or more after antigen it is ineffective. If added with antigen it can be removed at 5 min but release will still be inhibited. In contrast, ethylenediaminetetraacetate (EDTA) and 2 deoxyglucose (2DG) still inhibit the reactions when added 5 min after antigen. During incubation of leukocytes for 90 to 120 min at 0 degrees C they react with specific antigen since they subsequently release significant quantities of histamine after washing and reincubation at 37 degrees C without addition of antigen. Such priming at 0 degrees C is at least equivalent to priming for 2 to 4 min at 37 degrees C. During antigen priming at 0 degrees C the cells are not activated beyond the step in the release sequence which is inhibited by diisopropylfluorophosphate (DFP). This is apparent from the undiminished inhibitory activity of DFP on these cells. Furthermore, cells primed with antigen at 0 degrees C in the presence of DFP release as much histamine after washing and incubation at 37 degrees D as control cells primed in the absence of DFP. Incubation of leukocytes with specific antigen at 37 degrees C for 3 min resulted in significant but not quite complete priming for subsequent histamine release in the absence of antigen. Most of these primed cells were not activated beyond the step inhibitable by DFP. However, some had completed the entire sequence including the release of histamine while others had not released their histamine but were not inhibited by DFP from subsequent release. After 5 min incubation with antigen at 37 degrees C almost all leukocytes had progressed beyond the stage which is inhibited by DFP. Incubation of leukocytes at 37 degrees C with DFP but without antigen for up to 15 min followed by washing did not impair subsequent antigen-induced histamine release by these cells. Thus, DFP was inhibitory under these conditions only after antigen activation of leukocytes.
0.831513
Hepatocarcinogenesis by diethylnitrosamine in rats fed high dietary levels of lipotropes.
The effects of high dietary levels of lipotropes on the carcinogenic activity of diethylnitrosamine (DENA) in rats were studied. All animals given DENA, with or without a dietary supplement, developed hepatocellular carcinomas. The mean survival times of all groups of rats dying with hepatocellular carcinomas after DENA treatment were determined. Choline, betaine, and folic acid consistently exerted no significant effect on those mean survival times. In rats receiving approximately equal to 2 mg DENA/day, methionine administration led to a slight but significant increase in the mean survival time of the carcinogen-treated rats, whereas vitamin B12 significantly lowered the survival time; neither substance altered the mean survival times of those treated with only 1.0 mg DENA/day. On the other hand, ethanolamine decreased the mean survival times of rats given 1.0 mg DENA daily, but had no effect on animals receiving 2 ml/day of carcinogen. Dimethylthetin (sulfur analogue of betaine), methotrexate, lecithin, and cephalin exerted no effect on the carcinogenic activity of DENA. The administration of dimethylthetin and betaine along with DENA led to markedly increased liver weights in animals dying of hepatocellular carcinomas, when compared to liver weights of animals treated with DENA alone.
0.879835
Incidence and nature of cytoplasmic hepatitis B antigen in hepatocytes.
Hepatitis B antigen (HB Ag) in the hepatocytic cytoplasm is detected by immunofluorescence after reaction with fluoresceinated antiserum to HB Ag or by electron microscopy as numerous 20- to 30-nm. tubular and circular structures in dilated cisternae of excess endoplasmic reticulum. On light microscopy, these hepatocytes can be recognized because their cytoplasm has a ground-glass appearance and stains with Gomori's aldehyde fuchsin. Aldehyde fuchsin-positive ground-glass hepatocytes were detected in all 14 asymptomatic carriers of HB Ag and in 16 of 60 HB Ag-seropositive patients with chronic hepatitis, but not in HB Ag-seropositive acute viral hepatitis or in various other HB Ag-seronegative liver diseases. These cells are helpful in identifying on light microscopy HB Ag carriers and a portion of patients with HB Ag-positive chronic hepatitis. Nuclear HB Ag did not stain with aldehyde fuchsin. Nucleic acids were not detected in the ground-glass cytoplasm by special stains at the light or electron microscopic level. We suggest that the tubular and circular structures in the hepatocytic cytoplasm are coat material of the hepatitis B virus or virally coded host cell reaction product rather than the complete hepatitis B virus.
0.853827
Advanced diffuse histiocytic lymphoma, a potentially curable disease.
Twenty-seven patients with advanced diffuse histiocytic lymphoma (reticulum-cell sarcoma) were treated with combination chemotherapy utilising nitrogen mustard (or cyclophosphamide), procarbazine, vincristine, and prednisone. Elven (41%) achieved a complete remission and only one of these has had a recurrence of tumour. The remaining ten complete responders were free of all evidence of tumour when last seen 26-105 months from the end of treatment. In contrast, all non-responders or partial responders have died. An interpretation of published survival data suggests that this virulent disease evolves quickly and is usally rapidly fatal if treatment is unsuccessful. Survival free of disease beyond 2 years from the end of treatment may be considered tantamount to cure. This definition of cure, previously applied only to patients treated with radiotherapy, seems applicable to patients who acheive complete remissions with modern drug treatment.
0.814818
Functional role of cholesterol in infection and autoimmunity.
Cholesterol binds to streptolysin O and related bacterial toxins. In normal serum, only a fraction of the cholesterol attached to lipoprotein is available for binding, probably as a cholesterol-peptide complex formed during catabolic breakdown of the lipoprotein. Cholesterol esterase produced by certain organisms--e.g., Staphylococcus pyogenes and Pseudomonas oeruginosa--augments this fraction both in vitro and in vivo. Endogenous esterase similarly increases the amount of cholesterol-peptide complex, a mechanism which may be activated as a feedback process following binding of toxin to the cholesterol component of the complex. These complexes will thus supply a readily available means of binding bacterial toxins before antibody formation begins; Cholesterol-peptide complexes, either alone or modified by binding to toxin, may function as autoantigens. It is postulated that immune complexes so formed may be involved in atherosclerosis either by directly damaging vessels walls or by cross-reaction of antibody with cell-membrane-bound lipoproteins which equilibrate with plasma-lipoproteins.
0.766185
Suppression of connective tissue impregnation in a silver technique for demonstrating nerve fibers.
A tissue pretreatment is introduced which effectively suppresses the silver impregnation of connective tissue and nonspecific background elements in peripheral nerve. The result is a selective impregnation of nerve fibers. The procedure utilizes fresh frozen sections and can be used with the Holmes (1947) or Bodian (1936) techniques. Fresh frozen sections are cut at 10 microns, mounted on slides and air dried for 5 minutes. They are fixed for 30 minutes in formol-sublimate (10% formalin saturated with mercuric chloride) and then placed into 0.5% iodine in 70% alcohol for 5 minutes followed by bleaching in 2.5% sodium thiosulfate for 2 minutes. After washing in running tap water for 10 minutes and a brief rinse in distilled water, impregnation is accomplished by the Holmes (1947) or Bodian (1936) procedure beginning with the step containing the aqueous silver solution. The results show an absence of impregnation of connective tissue and nonspecific background. The technique is simple, rapid, and, by utilizing fresh frozen sections, can be used for other histological and histochemical purposes. Several experiments were done to determine the causes of the connective tissue and background suppression. The air drying step was omitted; the sections were fixed in formalin without mercuric chloride; and the formol-sublimate fixation time was increased. The results suggest that connective tissue impregnation is suppressed by the use of mercuric chloride in the fixative and that the background suppression is related to the short fixation time with formolsublimate.
0.855905
Interaction of contraceptive progestins and related compounds with the oestrogen receptor. Part I: Effect on (3H)oestradiol distribution pattern in the ovariectomized rat.
The distribution pattern of oestradiol in ovariectomized rats as a function of time has been studied following intravenous adminstration of the tritiated hormone. Oestrogen specific binding with limited capacity was observed in the uterus, vagina, anterior pituitary, adrenals, preoptic area, hypothalamus, amygdala, septum and tractus diagonalis. Maximal uptake of oestradiol in the pituitary occurred within 5 min, in the uterus 60 min after injection, and remained almost unchanged at this level for more than two hours. The binding capacity per mg tissue decreased in the order pituitary, uterus, vagina, preoptic area, adrenals, hypothalamus, amygdala, spetum and tractus diagonalis. The hormone concentration in these tissues one hour after (3H)oestradiol injection was lowered by previous administration of ethinodiol, norethinodrel, lynestrenol and norethindrone, whereas medroxyprogesterone, chlormadinone, megestrol and methyllynestrenol had no effect. The same results were obtained, when instead of the steroid alcohols the corresponding acetate esters were administered. For norgestrel, oestrenol and nortestosterone the effect in the dose range studied was limited to the pituitary and preoptic area. For lynestrenol the inhibition of oestradiol binding in the target tissues was almost the same when the progestin was given 60 and 5 min before oestradiol, whereas in the case of administration 30 min after oestradiol no inhibition was observed. The reduction of oestrogen binding appeared to be dose-dependent, but the dose required to obtain a certain effect for the uterus was four times as high as for the pituitary. Discrepancies between previous studies and the implications of the present findings for the mechanism of action of ovulation inhibition by these progestins are discussed.
0.869236
Post-jejunoileal-bypass hepatic disease. Its similarity to alcoholic hepatic disease.
The authors studied serial hepatic biopsies of five patients who developed hepatic failure following jejunoileal bypass for extreme obesity, with autopsies of two. The hepatic histologic changes included centrilobular or focal alcoholic hyalin, intrasinusoidal collagenosis, fatty hydropic degeneration, and neutrophilic infiltrate. At least two of the patients were abstinent from alcohol, both prior to and after the surgical procedures. The others, after the bypass procedures, had reduced alcohol consumption from previous levels. All patients developed hepatic failure and histologically progressive hepatic disease with alcoholic hyalin and other changes indistinguishable from alcoholic hepatic disease in 21/2 to 5 months, in spite of hyperalimentation and re-establishment of intestinal continuity in four. Nausea, vomiting, abdominal pain and ascites were prominent complaints. Four of the five patients died in hepatic failure. The authors conclude that these cases of progressive hepatic disease with histologic changes simulating those found in livers of alcoholic patients offer evidence that heavy alcohol consumption may affect the liver in an indirect fashion.
0.90351
Nephropathy associated with sickle cell anemia: an autologous immune complex nephritis. I. Studies on nature of glomerular-bound antibody and antigen identification in a patient with sickle cell disease and immune deposit glomerulonephritis.
The nature of the glomerular-bound antibody and the putative antigen was investigated in one of the patients with sickle cell disease and immune deposit membranoproliferative glomerulonephritis by immunohistologic and glomerular antibody elution. Renal proximal tubular epithelial antigen was localized in association with immunoglobulins G (IgG), M (IgM), Clq fraction of the first component of complement (Clq) and the third component of complement (C3) in a granular pattern along the glomerular basement membrane of the patient's kidney. IgG and IgM were eluted from glomeruli. These immunoglobulins fixed to the proximal tubules of normal human kidney by direct immunofluorescence. This localization was abolished by absorption of the eluted immunoglobulins with renal tubular epithelial (RTE) antigen. The IgG eluted from the glomeruli blocked the fixation of rabbit anti-RTE antigen to normal proximal tubular brush border. These studies suggest that the nephritis in this patient was due to deposition of complexes or RTE antigen and specific antibody. An autologous immune complex nephritis may develop in some patients with sickle cell anemia secondary to RTE antigen released possibly after renal ischemia or some other phenomenon causing renal tubular damage.
0.863184
The roentgenographic and clinical findings in Whipple's disease. A review of 8 patients.
Out of 8 patients with Whipple's disease, 7 had roentgenographic findings consisting of slight dilatation of the small bowel, with thickening of the mucosal folds. The eighth patient had no abnormality on roentgenographic study. This series represents the first in which the roentgenographic changes have been quantitatively assessed. Confirmation of the diagnosis by biopsy is important because antibiotic treatment results in marked improvement both clinically and roentgenographically.
0.896294
Reaction of cultured adult and fetal lung to prednisolone and thyroxine.
Pulmonary explants from adult mice were cultured for periods up to six days in medium with and without one of the following agents: prednisolone, thyroxine, puromycin, actinomycin. Both DNA synthesis and tritiated palmitic acid uptake were greatly reduced by puromycin and actinomycin, which killed the cultures in six days. Prednisolone accelerated uptake of lipid precursor and decelerated DNA synthesis; thyroxine treated explants were not different from controls. Lamellar bodies were observed only in the epithelial cells of cultured explants exposed to prednisolone. Similarly, cultures of fetal lung exhibited maturation with appearance of lamellar bodies only when prednisolone was administered. The depression of cellular division and the stimulation of palmitic acid uptake with coicident appearance of lamellar bodies in cultures exposed to prednisolone supports the hypothesis that control of the differentiation of alveolar epithelium with synthesis of phospholipid surfactant, is a function of the adrenal cortex.
0.849666
Morphologic and functional characteristics of bone marrow macrophages from imferon-treated mice.
The iron storage macrophage has been isolated from the marrow of Imferon-treated mice and studied in vitro by morphologic, histochemical, and functional tests and isotope labeling techniques. These macrophages on stained preparations are large, many times binucleate cells (up to 150 mu), and show Prussian blue reactivity. In Epon-embedded, stained thick sections they contain elongated narrow basophilic inclusions. These macrophages are actively phagocytic and pinocytic; histochemical studies show that these cells are rich in acid phosphatase, nonspecific esterase, and PAS diastase-resistant activity. Iron storage macrophages do not incorporate the 3H-thymidine. The electron microscopic appearance of this macrophage shows that the cell has ferritin free in the cytoplasm and several types of cytoplasmic granules: those with large quantities of electron-dense ferritin and/or hemosiderin (type A), elongated granules (type B) with moderately electron dense homogeneous matrix and some ferritin at the periphery, and granules with heterogeneous content (type C). The above findings demonstrate that the iron storage cell is a mature macrophage which contains hydrolases, ferritin, and a unique population of cytoplasmic granules which are lysosomal in nature. There is some evidence to suggest that the unusual lysosome (type B granule) occurs after macrophages have ingested erythrocytes.
0.802327
A clinical evaluation of indium-111 bleomycin as a tumor-imaging agent.
In an evaluation of indium-111-bleomycin as a tumor-imaging agent, 357 whole-body tumor scans were performed in 293 patients. Of 246 studies performed in patients with a variety of active solid tumors, 218 (89%) were true-positive studies and 28 (11%) were false-negative. Of 69 scans in patients thought to be free of tumor after therapy, 32 (46%) were false-positive studies and 37 (54%) were true-negative. The true-positive rates by major tumor type were: adenocarcinoma of gastrointestinal tract origin (95%), lymphoma (88%), melanoma (87%), sarcomas (82%), lung (77%), breast (77%), childhood tumors (71%), gynecologic tumors (70%), and genitourinary tumors (68%). Soft tissue and lymphatic sites of tumor, both above and below the diaphragm, were easily visualized, whereas hepatic and bone marrow sites of involvement were less easily discerned. False-positive uptake with 111In-bleomycin was noted in lungs (6%), gut (3%), mediastinum (2%), normal breast tissue (0.8%), and in occasional inflammatory lesions. In 19 patients with multiple myeloma or leukemia, a pattern of diminished bone marrow uptake associated with abnormal accumulation of 111In-bleomycin in extramedullary sites of involvement was the rule. In another 23 patients in whom scans were performed because an occult tumor was suspected, scanning did not lead to specific diagnosis of tumor in a single instance. We conclude that 111In-bleomycin is a safe, effective, and useful new tumor-imaging agent in the initial staging and followup of patients with a variety of solid tumors. Significant advantages of this agent over other currently available radiopharmaceuticals include: A) a broader spectrum of tumors taking up the radio-pharmaceutical, and B) generally better delineation of abdominal and pelvic disease due to lack of interference from gut uptake.
0.907029
Detection of latent function in acutely ischemic myocardium in the dog: comparison of pharmacologic inotropic stimulation and postextrasystolic potentiation.
In poorly perfused myocardium with resultant ischemic dysfunction, augmentation of contractility can, under certain conditions, be used to detect viable but ordinarily noncontracting muscle. Two methods of inotropic augmentation, pharmacologic inotropic stimulation and postextrasystolic potentiation (PESP), were studied in acutely ischemic canine myocardium with controlled coronary blood flow. A caliper length gauge to record segmental shortening and left ventricle pressure was used to construct pressure-length loops. Acute regional ischemia depressed segmental function: early segmental shortening decreased (-20 plus or minus 0.02% [SE]) and frequent dyskinesia occurred. Restoring coronary blood flow corrected segmental shortening to control levels. During acute regional ischemia, PESP consistently augmented segmental function (+49 plus or minus 0.03%) and abolished dyskinesia. Pharmacologic inotropic stimulation with isoproterenol or calcium administered into the coronary arteries did not produce a comparable improvement in segmental function (+9 plus or minus 0.05%). Although early shortening markedly increased with pharmacologic stimulation, there was no consistent change in total shortening, and the area of the pressure-length loop decreased. Due to late dyskinesia, there was a decrease in injection shortening. Systemically administered pharmacologic agents accentuated early dyskinesia but caused no consistent change in total shortening. Unlike PESP, pharmacologic agents either worsened segmental function or caused responses that were minimum and inconsistent; such responses clearly cannot be used to identify viable ischemic myocardium.
0.842267
Microanalytical system for determination of picogram quantities of metals in metalloenzymes, as illustrated with zinc-containing enzymes.
Microwave-induced emission spectrometry combined with gel-exclusion chromatography provides a microanalytical system capable of precisely measuring 10 minus 10 to 10 minus 13 g of metal in microgram amounts of enzyme. Such sensitivity greatly exceeds that of other, more conventional methods. Metal quenching agents and low-molecular-weight protein contaminants were removed from the enzyme by Sephadex G-100 chromatography in microbore columns (0.03 times 25 cm). Droplet fractions were analyzed for zinc by the present method, for enzyme activity, and for protein content. With this analytical system we could demonstrate that stoichiometric amounts of zinc are present in the RNA-dependent DNA polymerase, the reverse transcriptase, from wooly monkey type C RNA tumor virus. The precision of the method for zinc was demonstrated by the coefficient of variation of 4.4 percent for 10 mug of zinc per liter. Validity and accuracy of the method were established by determining zinc in a series of zinc metalloenzymes of known metal content and stoichiometry.
0.876096
The late positive component (P300) and information processing in sentences.
Averaged visual evoked potentials to sequentially flashed words comprising a sentence were recorded from vertex and left and right temporoparietal electrodes in 8 right-handed subjects. In condition 1 the sentence took the form: The -eel is on the shoe, in which the first grapheme was omitted from the second word, so that the subject did not know the meaning of the second word until he viewed the last word. In condition 2, the sentence took the form: The heel is on the shoe, in which the second word was given and the last word provided no further information. P300 latency to words which delivered information (last word of condition 1, second word of condition 2) were significantly longer than P300 latency to any of the other words in the sentence, as well as to the same position word in the other condition. Comparisons of P300 latencies to redundant words (the, is, on) within and between conditions showed no significant differences. P300 amplitude to the last word was significantly larger than P300 amplitude to any of the other words within the sentence, even in condition 2 where the second word delivered information. The major effect of information delivery was on P300 latency, while "syntactic closure" had its major effect on P300 amplitude. The fact that evoked potentials to all words had P300 components was attributed to the engagement of the P300 system whenever task-related language stimuli are used.
0.867552
An application of long-term frequency analysis in measuring drug-specific alterations in the EEG of the cat.
A method is described for the quantitative measurement of "drug-specific" effects on the EEG of the cat. These effects are dose-related and are independent of the normal sources of EEG variation associated with the sleep-waking cycle. Drug-induced changes are expressed as characteristic alterations in frequency spectra and the time courses of these effects are followed for 5 h following administration of the test compounds. Atropine sulfate (0.5 and 2.0 mg/kg) and physostigmine salicylate (0.05 and 0.20 mg/kg) were administered to three unanesthetized and unrestrained cats and a broad-band frequency analysis was performed on the spontaneous brain electrical activity recorded from the prepyriform cortex, ventral hippocampus, lateral geniculate nucleus and the midbrain reticular formation. The resulting data were used as input to discriminant and canonical statistical analysis programs employed to abstract "drug-specific" patterns of frequency change. It was found that both atropine and physostigmine produce alterations in EEG frequency spectra which are clearly distinct from those patterns associated with the sleep-waking cycle and thus neither compound results in what has been characterized as an "EEG-behavioral dissociation".
0.862218
Human frequency-following responses to monaural and binaural stimuli.
Frequency-following responses, with latencies circa 6 msec, were recorded from five normal-hearing human subjects to brief 500 c/sec tone bursts presented monaurally. The frequency-following responses appear as peaks occurring at 2 msec intervals superimposed on a slow wave (pedestal-like) component. Comparisons were made between the frequency-following responses evoked by binaural and monaural stimuli. The results show that the binaural responses may be interpreted as the sum of two monaural responses. It is concluded, therefore, that there are two independent populations of neurons, each capable of generating a frequency-following response is not a microphonic-like response but rather that the individual waves in the frequency-following response are evoked by the collective activity of phase-locked single units. Finally, on the basis of the distinctness of the individual waves in the frequency-following response, it is concluded that the neural generators of the response must be spatially compact.
0.884644
Localization of a protein antigen in the chicken spleen. Effect of various manipulative procedures on the morphogenesis of the germinal centre.
The time course of the localization of a protein antigen human serum albumin (HSA) into the chicken spleen after intravenous injection is analysed. Localization within seconds to the region surrounding the Schweigger-Seidel sheaths is accomplished by HSA complexes with chicken anti-HSA or by heat aggregated HSA. The localization of soluble HSA has to await the synthesis of sufficient chicken anti-HSA to accomplish localization to the same white pulp sites in the spleen at 25-30 hours after injection. By the use of complexes of HSA-anti-HSA in ten times antigen excess, the time for localization of HSA withing germinal centres was accelerated as compared with soluble HSA, so that newly formed centres containing antigen-bearing dendritic ells were seen at 48 hours instead of 72 hours after use of soluble HSA. Neonatally bursectomized and irradiated (Bx+Irr.) birds fail to localize HSA into germinal centres or to dendritic cells within the white pulp. Heat-aggregated human gamma-globulin (HGG) injected intravenously into Bx+Irr. birds rapidly localizes within seconds to the periphery of Schweigger-Seidel sheaths and at 24 hours can be seen attached to the surface of typical dendritic cells throughout the white pulp. Hence, heat-aggregated HGG can localize to dendritic cells in the absence of specific antibody. However, such localization to dendritic cells in Bx+ Irr. birds is not followed by segregation of the aggregated HGG-bearing dendritic cells within germinal centres--a further stage in the process which is presumed to require B cells and/or specific antibody. Localization of heat-aggregated HGG to white pulp dendritic ells was prevented by treatment with pepsin sufficient to destroy the ability of aggregated HGG to activate guinea-pig complement. Similary, in vivo decomplementation with a purified anticomplementary fraction (CoF) from the venom of Naja naja resulted in failure of intravenously injected HSA to localize to white pulp dendritic cells and failure of subsequent germinal centre formation. However, such decomplementation did not prevent the localization of aggregated HGG to white pulp dendritic cells. These facts are discussed in the light of hypotheses concerning germinal centre formation and the homeostasis of the antibody response in the bird.
0.839164
Studies in immunodermatology. VI. IF studies of autoantibodies to the stratum corneum and of in vivo fixed IgG in stratum corneum of psoriatic lesions.
Indirect immunofluorescent (IF) tests on sections of normal human skin reveal the presence of antibodies to the stratum corneum in most normal human sera. Sera absorbed with hyperkeratotic scales gave negative reactions. These reactions appeared to correspond to those of the stratum corneum antibodies which were first detected by Krough and Tonder by immune adherence, though this remains to be documented since the conjugate alone stained the stratum granulosum in a pattern comparable to that of the IF staining reported by Krough. The staining was caused by conjugates with high but not by those with low fluorescein to protein ratios. In indirect IF tests, comparable titers of stratum corneum antibodies were found in sera of psoriasis patients and control subjects. Since they reacted with the stratum corneum of the antibody producer they are referred to as autoantibodies. Direct IF tests of psoriatic lesions revealed the presence of in vivo bound IgG as well as other immunoglobulins and complement in the stratum corneum. To differentiate staining with conjugated protein from direct and indirect IF staining of the stratum corneum a four-compartment test was devised. Skin sections were treated with saline or with stratum corneum antibodies and then with conjugates without (compartments 1 or 2) or with (compartments 3 or 4) anti-IgG antibodies. Sections were read by the method of Kawamura and his associates with both UV and BV illumination. Compartment 3 is a direct IF test and compartment 4 is an indirect IF test. In four-compartment tests performed on both biopsies of psoriatic lesions or scales the difference between compartments 1 or 2 and 3 affords a measure of in vivo bound IgG and the difference between compartments 3 and 4 provides information on the presence of free stratum corneum antigen. With this four-compartment test system it was found that in vivo fixation of IgG occurs in the intercellular areas of the stratum corneum of psoriatic lesions or scales and that this corresponds to the site of binding of the stratum corneum autoantibodies. This in vivo binding of IgG in the stratum corneum of psoriatic lesions resembles somewhat the intercellular fixation of IgG in the stratum spinosum in pemphigus. In the materials examined in these preliminary studies most, if not all of the stratum corneum antigen appeared to be covered with in vivo bound IgG.
0.873709
Optical versus radiographic magnification for fine-detail skeletal radiography.
Fine-detail radiographic techniques for peripheral skeletal imaging have gained wide clinical acceptance. In this study, the imaging properties and clinical applications of the optical magnification technique, which employs fine-grain industrial film and a large focal spot, are compared quantitatively and qualitatively with those of three slow screen-film techniques, namely, contact exposure with a large focal spot, 2 times radiographic magnification with a 0.3 mm focal spot, and 4 times radiographic magnification with a 50 mu focal spot. The modulation transfer functions (MTF's) of the recording systems and focal spots are obtained and film sensitometry performed. Clinical comparisons are made for patients with metabolic, arthritic, and neoplastic skeletal disorders. The results illustrate the superiority of the optical magnification technique over contact or 2 times magnification techniques using slow screen-film systems. If a microfocus tube is used, however, direct radiographic magnification may provide images comparable in resolution, noise and contrast to those made with the optical magnification technique, and at lower radiation exposure to the patient.
0.898228