Search PubMed⌕ Search

Biomedical subjects

H Singh

Publications and source records attributed to H Singh.

At least 271 records · Page 15Linked to original sources

Sleep pattern and night awakening in healthy infants.

Sleep pattern and night-awakening were studied in 500 healthy infants by a semistructured interview method. A total of 92.2% infants shared bed with their mothers, 6.8% with grand parents and 1% with fathers. Paternal participation at bedtime was observed to be insignificant. Infants of non-working mothers and families with vegetarian habits slept significantly more as compared to the working mothers and families with non-vegetarian habits. Night-time awakening was reported in 96% of the infants. If a child is functioning well in other areas of life, parents can be assured that the problem is not of serious concern and unnecessary medication of infants should be avoided.

Age Factors↗

Peroxisomal beta-oxidation of branched chain fatty acids in human skin fibroblasts.

Human skin fibroblasts in suspension are able to degrade [1-14C]-labeled alpha- and gamma-methyl branched chain fatty acids such as pristanic and homophytanic acid. Pristanic acid was converted to propionyl-CoA, whereas homophytanic acid was beta-oxidized to acetyl-CoA. Incubation of skin fibroblasts with [1-14C]-labeled fatty acids for longer periods produced radiolabeled carbon dioxide, presumably by further degradation of acetyl-CoA or propionyl-CoA generated by beta-oxidation. Under the same conditions similar products were produced from very long chain fatty acids, such as lignoceric acid. Inclusion of digitonin (> 10 micrograms/ml) in the incubations strongly inhibited carbon dioxide production but stimulated acetyl-CoA or propionyl-CoA production from fatty acids. ATP, Mg2+, coenzyme A, NAD+ and L-carnitine stimulated acetyl-CoA or propionyl-CoA production from [1-14C]-labeled fatty acids in skin fibroblast suspensions. Branched chain fatty acid beta-oxidation was reduced in peroxisome-deficient cells (Zellweger syndrome and infantile Refsum's disease) but they were beta-oxidized normally in cells from patients with X-linked adrenoleukodystrophy (ALD). Under the same conditions, lignoceric acid beta-oxidation was impaired in the above three peroxisomal disease states. These results provide evidence that branched chain fatty acid, as well as very long chain fatty acid, beta-oxidation occurs only in peroxisomes. As the defect in X-linked ALD is in a peroxisomal fatty acyl-CoA synthetase, which is believed to be specific for very long chain fatty acids, we postulate that different synthetases are involved in the activation of branched chain and very long chain fatty acids in peroxisomes.

Antimycin A↗

Stool electrolytes in acute dehydrating gastroenteritis.

Stool electrolytes were studied in 100 cases of gastroenteritis. The duration of illness was 24-48 hours in 32% and 72-96 hours in 28% of the cases. On stool culture, 43% children had no growth, 23% had Enteropathogenic E. coli and 10% had cholera and rotavirus each. The stool sodium loss was more in cholera and shigella cases, diarrhea of shorter duration and in children between 24-30 months of age. Potassium loss in the stool was more in shiegella cases, diarrhea of short duration and in children between 30-36 months of age. In cases of gastroenteritis with severe malnutrition, stool sodium loss was less; stool potassium loss was not affected by the nutritional status. Total electrolytes lost in stools can be estimated by knowing purging rate and rehydration therapy can be planned accordingly.

Acute Disease↗

Pattern of substance abuse among secondary school students in Trinidad and Tobago.

A questionnaire survey of 1,603 secondary school students, aged 14-18 years, was conducted in Trinidad and Tobago in 1988. Prevalence of alcohol use was 84%, tobacco 35%, marijuana 8% and cocaine 2%. Alcohol was the substance most consistently used and students' first exposure to drinking alcohol was with family members. Transitions from primary to secondary schools and from junior to senior schools were associated with increased reporting of alcohol use. Significantly more Indo-Trinidadian than Afro-Trinidadian students reported using alcohol frequently. Conversely more Afro-Trinidadian students than Indo-Trinidadians reported using marijuana. The use of alcohol by students was positively correlated to its use by fathers and negatively with religious activities. The use of drugs among students appears to be a growing problem. There is a need for the implementation of culturally relevant educational prevention programmes in schools.

Adolescent↗

Selecting for efficiency of egg production using food-consumption records in layer-type chickens.

1. The purpose of the experiment was to evaluate the use of food consumption records in selection to improve layer-type chickens. 2. Twelve subpopulations of Leghorns, including 5878 tested birds, were used in a selection experiment which lasted 5 generations. Four were selected using an index (I1) that combined information on body weight (BW), egg-mass output (EM), and individual food-consumption records (FC). Four were selected using an index (I2) that combined information just on BW and EM. The remaining 4 served as controls, with selection differentials set to zero in each generation. 3. Differences between the selected groups, control-corrected each generation, measured the "food-record effect". 4. Including food-consumption records in the selection criterion resulted in increased body weight (7%), reduction in food consumption (6 to 9%), increase in food efficiency (egg mass/food consumption) (2 to 5%), and increase in income over food costs (10%), relative to selection not involving food records.

Animals↗

End-tidal CO2 monitoring in mitral stenosis patients undergoing closed mitral commissurotomy.

Arterial to end-tidal carbon dioxide difference (P(a-E')CO2) was recorded in 20 mitral stenosis patients (group A) for closed mitral commissurotomy and 20 healthy individuals (group B) for elective limb surgery. Mitral stenosis patients showed a greater difference than group B patients. Repeated measurements of P(a-E')CO2 in mitral stenosis patients at various stages of closed mitral commissurotomy not only showed a mean increase from before thoracotomy but there was also no correlation between P(a-E')CO2 before thoracotomy with that after thoracotomy, after commissurotomy or after chest closure. This indicated that end-tidal CO2 monitoring was unsuitable to measure adequacy of ventilation during closed mitral commissurotomy.

Adult↗

Glyceryl ethers in peroxisomal disease.

1-O-Alkyl and 1-O-alk-1-enyl (plasmalogens) glyceryl ether lipid levels were measured in post-mortem brain and/or liver biopsies from 7 patients with ultrastructural and biochemical evidence of a defect in peroxisomal biogenesis and/or enzymological evidence of a disturbance in ether lipid synthesis. Near normal levels of both species of glyceryl ether lipids were found in neonatal adrenoleukodystrophy and infantile Refsum's disease but marked deficiencies were found in Zellweger's syndrome and rhizomelic chondrodysplasia punctata, the latter manifesting the most profound reduction in ether lipid levels. These observations suggest that little ether lipid biosynthesis occurs in vivo in rhizomelic chondrodysplasia punctata or Zellweger's syndrome. However, in some phenotypes with apparently gross reductions in peroxisomal numbers, e.g. neonatal adrenoleukodystrophy and infantile Refsom's disease, there is significant ether lipid synthesis in liver and brain.

Adrenoleukodystrophy↗

Evaluation of triflupromazine as a sedative in camels (Camelus dromedarius).

Effects of administration of triflupromazine were evaluated in 11 adult domesticated camels (Camelus dromedarius) weighing 403 +/- 29.5 kg (Mean +/- SE). Six camels were used to evaluate sedative properties of the drug and its effects on haematological and blood biochemical parameters. In the remaining 5 camels, effects on haemodynamics, acid base status and blood gases were studied. In all the animals triflupromazine was administered intramuscularly in the gluteal region at the rate of 2 mg/kg. Camels voluntarily sat down 48.9 +/- 5.4 min after administration of the drug but stood up again if disturbed. Drowsiness, drooping of lower lip and salivation were evident. The animals stood on their own and started walking with ataxia after 159 +/- 7 min and recovered completely from the effect of drug within 259 +/- 23 min. The drug caused a significant tachycardia and a moderate hypotension. The decrease in central venous pressure was also significant. Rectal temperature, respiratory rate, acid base status, blood gases, haemoglobin concentration, packed cell volume, total erythrocyte count, total leucocyte count, differential leukocyte count, blood urea nitrogen, plasma alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, alkaline phosphatase, blood glucose and plasma concentrations of sodium, potassium, chloride and inorganic phosphate were not significantly affected by triflupromazine.

Animals↗

Studies of cardiovascular and arterial blood gas changes during carbon dioxide pneumoperitoneum for laparoscopic sterilization under general anaesthesia versus local anaesthesia.

This study was conducted to evaluate the different change in arterial blood gases and cardiovascular system in 50 healthy females during laparoscopic sterilization procedure performed under general or local anaesthesia. Women who had laparoscopic sterilization under local anaesthesia, showed an increase in respiratory rate by 17% in response to hypercarbia produced by carbon dioxide insufflation. Subjects undergoing laparoscopic sterilization under general anaesthesia showed significant rise in pulse rate by 6% and systolic and diastolic blood pressure by 8% and 14%, respectively. Also arterial blood gas analysis showed increase in PaO2 by 22.7% which was highly significant. However, PaCO2, pH and base were maintained within normal limits as compared to the other group done under local anaesthesia, where no changes were observed.

Anesthesia, General↗

Regulation and a possible stage-specific function of Oct-2 during pre-B-cell differentiation.

The Oct-2 gene appears to encode a developmental regulator of immunoglobulin gene transcription. We demonstrate that the Oct-2 gene is expressed at low levels in a variety of transformed pre-B-cell lines and is induced specifically in these cells by lipopolysaccharide signalling. This work extends an earlier observation in the pre-B-cell line 70Z/3 and therefore suggests that the inducible expression of the Oct-2 gene, like that of the kappa gene, is a characteristic feature of the pre-B stage of B-cell development. In 70Z/3 cells, the lymphokine interleukin-1 also induces the expression of the Oct-2 and kappa loci. Interestingly, expression of the Oct-2 gene is rapidly induced at the transcriptional level and may not require de novo protein synthesis. Since the changes in the activity of the Oct-2 locus completely correlate with the changes of the activity of the kappa locus, the two genes may be transcriptionally regulated by a common trans-acting factor. In 70Z/3 cells, transforming growth factor beta, an inhibitor of kappa-gene induction, blocks the upregulation of Oct-2 but not the activation of NF-kappa B. These results suggest that the combinatorial action of increased levels of Oct-2 and activated NF-kappa B may be necessary for the proper stage-specific expression of the kappa locus.

Animals↗

Antibacterial multifilament nylon sutures.

Multifilament nylon fibers were made antibacterial by dopping with iodine. Nylon fibers were immersed in acetone solution of iodine for 48 hours at room temperature for dopping of iodine. It was observed that iodine uptake by the nylon fibers increased with the increase in concentration of iodine in the solution. Antibacterial activity of these iodine dopped samples was evaluated by measuring the zone of inhibition. The bacterial species used for this study were Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Klebsiella pneumoniae. Iodine dopped fibers exhibited good antibacterial activity against these bacterial species. Release of iodine in distilled water is sustained for about 30 days. Antibacterial activity of the fibers decreases with the release of iodine in water. Ultra-violet and visible spectroscopic studies showed that tri-iodide ions were released from the dopped samples in the aqueous medium. These I3- ions might be responsible for the observed antibacterial activity. Fiber shrinks on iodine dopping leading to increase in the denier of the fiber. However effect of iodine dopping on the breaking load of fibers is not significant.

Anti-Infective Agents, Local↗