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M Singh

Publications and source records attributed to M Singh.

At least 1,027 records · Page 57Linked to original sources
PubMed1984

Effect of ethanol on the uptake of pyridoxine X HCl in the rat jejunum.

The effects of acute ethanol exposure and chronic ethanol ingestion on jejunal mucosal uptake of 2 microM pyridoxine X HCl (PN) was studied in rats. Experimental models included in vitro everted sacs and in vivo perfused segments. The presence of 4% w/v but not 1% w/v ethanol (mucosal side) acutely enhanced PN uptake by 30 to 76%. Ethanol removal rapidly returned uptake rates to base-line. Histological evidence of mucosal injury in perfused segments paralleled observed changes in PN uptake. After chronic ethanol ingestion (1 yr), PN uptake from media without added ethanol was not statistically different from control values. Conclusions are: 1) acutely, enhancement of PN mucosal uptake by ethanol in rat jejunum is associated with the presence of a high ethanol concentration, is rapidly reversible, and correlates with histological evidence of mucosal injury; and 2) chronic ingestion of ethanol appears to have no further effect on PN uptake in the rat.

Animals↗
PubMed1984

Detection of occult blood in gastric juice.

The detection of occult blood in gastric fluid samples may be clinically important, but many current methods are too sensitive. Gastric fluid containing various concentrations of blood were subjected to analysis by four screening methods. Orthotolidine based tests (Hematest reagent tablets and Bili-Labstix) designed for urinary and fecal blood detection when applied to gastric aspirates were highly accurate, but sensitivity was so great that normal fluid yielded positive results. Guaiac slide tests (Hemoccult and Gastroccult slide tests) were less sensitive than the orthotolidine-based tests. The Hemoccult slide test was influenced by the low pH of gastric aspirates and neutralizing the acidity of the gastric fluid by addition of NaOH improved the sensitivity of the method. The Gastroccult slide test accurately determined gastric fluid pH and hemoglobin concentration greater than 300 micrograms/dl in the acid environment of gastric fluid. The Gastroccult slide test is a simple, rapid, and convenient method for initial evaluation of patients suspected of occult blood in gastric juice.

Gastric Juice↗
PubMed1984

Folate deficiency and pancreatic acinar cell function.

The present study was designed to determine the effect of folate deficiency on pancreatic acinar cell function. In the first series of experiments, three groups of rats were fed ad libitum regular rat feed, folate-deficient diet, or an equivalent amount of folate-sufficient diet. In the second series of experiments, rats were either fed ad libitum or rendered folate deficient by a purified folate-deficient diet; half of the folate-deficient group was replenished with oral folate. Body weight, pancreatic weight, DNA [methyl-14C]thymidine incorporation into DNA, RNA, [8-14C]adenine incorporation into RNA, protein content, synthesis of proteins, amylase content, and basal and bethanechol-stimulated amylase secretion were determined. The parameters were the same in the rats fed a folate-sufficient diet as in those fed a regular rat feed. Feeding a folate-deficient diet resulted in impaired DNA synthesis as evidenced by diminished incorporation of [methyl-14C]thymidine into DNA. There was no change in secretion of amylase. Similar results were obtained in the second series of experiments. These studies indicate that folate deficiency (rather than antibiotic content of the diet) impaired pancreatic function. Folate deficiency may therefore contribute to pancreatic injury in malnutrition and alcoholism.

Amylases↗
PubMed1984

Studies on filariasis in Singapore: immunodiagnosis using indirect immunofluorescence.

Filarial antibodies were detected by the indirect fluorescent antibody (IFA) technique using sonicated microfilariae of Brugia malayi as antigen. Of the 324 sera of patients with clinical symptoms suggestive of filarial infection, 90 (28%) had detectable antibodies with titres ranging from 1 : 4 to 1 : 4096. Forty-six percent of patients with eosinophilic lung were positive with titres ranging from 1 : 4 to 1 : 1024. Highest rates of positives were seen in Indians (48%) with lower rates in Malays (36%) and Chinese (15%).

Animals↗
PubMed1983

Effects of maternal diabetes on the levels, synthetic rates and activities of synthetic enzymes of surface-active phospholipids in perinatal rat lung.

Streptozotocin-induced maternal diabetes in the rat has been found to reduce selectively the content and synthetic rates of disaturated phosphatidylcholine and lysophosphatidylcholine in the lungs of term fetuses. Furthermore, the elevations in these parameters which occur during normal pulmonary maturation between the final gestational day and the first neonatal day are abolished or markedly curtailed, resulting in significantly reduced levels and synthetic rates of surfactant and its immediate precursor in the neonatal lung. In addition, complete or partial inhibition of the perinatal developmental rise in the activities of key enzymes catalyzing de novo phosphatidylcholine synthesis in the lung, viz., cholinephosphate cytidylyltransferase and cholinephosphotransferase, and of enzymes catalyzing reacylation of unsaturated to disaturated phospholipid, viz., lysophosphatidic acid and lysophosphatidylcholine acyltransferases, has been observed, resulting in reduced activities of these enzymes in the neonate. The observed reductions in surface-active phospholipid synthesis in the lungs of offspring of diabetic mothers may be related to these lowered enzyme activities, as well as to deficiencies in carbohydrate precursors available for phospholipid synthesis, as reported in previous studies. It is suggested that the hyperinsulinemia manifested in fetuses of diabetic mothers opposes the tendency of corticosteroids to enhance surface-active phospholipid synthesis, resulting in pulmonary surfactant deficiency and thus the propensity for neonatal respiratory distress.

Animals↗
PubMed1983

Nif-hybrids of Enterobacter: selection for nif gene integration with chlorate.

The nif gene group from Klebsiella can be transferred into Enterobacter cloacae by conjugation using Escherichia coli donor cells carrying the composite self-transmissible nif-plasmid pRD1. A small fraction of the hybrids obtained is stable upon prolonged passaging without selection. Their stability is due to integration of pRD1 into the chromosome. Such integration hybrids were chlorate resistant, and nitrate reductase negative, which indicated that integration preferentially occurred within one of the genes for the production or functioning of this enzyme. Chlorate resistance could, therefore, be used to select for additional nitrate reductase-negative sublines with pRD1 in their chromosome. Such sublines have been analyzed further for the presence of nif genes, other pRD1 markers, and for stability. In all except one the complete plasmid seems to have been integrated. Some tend to revert to nitrate utilisation (chlorate sensitivity).

Chlorates↗
PubMed1983

Effect of chronic ethanol feeding on pancreatic enzyme secretion in rats in vitro.

The effect of long-term ethanol intake on pancreatic digestive enzyme secretion was determined in Sprague-Dawley rats. Weight-matched triplets were fed Lieber-DeCarli diet containing 5% w/v concentration of ethanol, isocaloric amounts of Lieber-DeCarli diet, or rat chow ad libitum for 6, 12, and 18 months. Basal and bethanechol-stimulated secretion of amylase, lipase, trypsinogen, chymotrypsinogen, and pancreatic secretory trypsin inhibitor (PSTI) was determined. In the ethanol-fed group, basal secretion of trypsinogen and chymotrypsinogen was increased at 6, 12, and 18 months. In addition, basal secretion of amylase and lipase was increased and that of PSTI was decreased at 12 and 18 months. Secretion of PSTI was stimulated by bethanechol (10(-4)M), whereas the secretion of digestive enzymes was not stimulated in the ethanol-fed versus two control groups. At 12 months the dose-response curve of amylase and lipase secretion was shifted upwards in the ethanol-fed group with increase in ED50. These data are suggestive of membrane perturbations leading to increased basal secretion and a subsensitivity of the cholinergic receptors in the ethanol-fed group. Increased basal secretion of proteases in the presence of diminished trypsin inhibitor indicates that premature activation of proenzymes could occur resulting in pancreatitis.

Amylases↗
PubMed1983

Seasonal variation in freezability of buffalo semen.

Fifty-six buffalo semen ejaculates of mass activity greater than plus three on a five-point scale (28 each in summer and winter seasons) were frozen in Tris yolk glycerol (TY-G) extender with four hours equilibration time. Motility of semen was checked after first extension (initial motility), after equilibration time, 15 minutes after freezing, and 30 days after freezing. Motility increased during winter season. Significant differences (P<0.01) in motility after freezing were observed between summer and winter seasons.

Journal Article↗
PubMed1983

Morbidity and mortality in childhood in Afghanistan: a study of 40 492, consecutive admissions to the Institute of Child Health, Kabul.

During a three-year period, 336029 children were accorded ambulatory care and 40 492 children were admitted to the Institute of Child Health, Kabul, for in-patient treatment. Sixty-three per cent were boys. Three-quarters (75.3%) were under five years of age and provided 81.7% of the overall mortality. Children with acute gastroenteritis and respiratory infections together accounted for 49.9% of all admissions and 34.5% of all deaths. Malnutrition of varying degrees was a core problem and was seen in 67% of hospitalized children. The infectious diseases as a single group accounted for 70.7% of the morbidity and 71.9% of the mortality. Septicaemia and infections of the central nervous system were associated with the highest case fatality rates, especially among newborn babies. Six-target diseases and accidents accounted respectively for 10.4 and 9.7% of all deaths. Sixty-three per cent of children died within 24 hours of admission and the majority of deaths occurred after regular hospital working hours. In order to safeguard the well being of children in Afghanistan, and to reduce their morbidity and mortality, it will be mandatory to ensure effective delivery of primary health care, improve nutritional standards, provide safe drinking water, immunize the vulnerable population, make free elementary education universal and improve the lot of women and future mothers.

Adolescent↗