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Biomedical subjects

R Singh

Publications and source records attributed to R Singh.

At least 451 records · Page 25Linked to original sources
PubMed1993

Sequence-specific binding of transfer RNA by glyceraldehyde-3-phosphate dehydrogenase.

A transfer RNA (tRNA) binding protein present in HeLa cell nuclear extracts was purified and identified as the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Studies with mutant tRNAs indicated that GAPDH recognizes both sequence and structural features in the RNA. GAPDH discriminated between wild-type tRNA and two tRNA mutants that are defective in nuclear export, which suggests that the protein may participate in RNA export. The cofactor nicotinamide adenine dinucleotide disrupted complex formation between tRNA and GAPDH and thus may share a common binding site with the RNA. Indirect immunofluorescence experiments showed that GAPDH is present in the nucleus as well as in the cytoplasm.

Amino Acid Sequence↗
PubMed1993

Biological evaluation of protein quality of sorghum as affected by insect infestation.

Protein quality of sorghum grains having 25, 50 and 75% infestation caused by mixed population of Trogoderma granarium Everts and Rhizopertha dominica Fabricius was biologically evaluated by rat growth and nitrogen balance studies. Feeding of diet containing insect infested sorghum grains (50 and 75%) resulted in marked decrease in food intake, protein intake, gain in body weight, food efficiency ratio, protein efficiency ratio, nitrogen consumption, nitrogen absorption, biological value, net protein utilization, dry matter digestibility, net protein retention and protein retention efficiency. These parameters showed negative association with insect infestation levels. However, 25% level of grain infestation did not affect these parameters significantly.

Analysis of Variance↗
PubMed1993

Available carbohydrates of cereal grains as affected by storage and insect infestation.

Total soluble sugar, reducing sugar, non-reducing sugar and starch contents of wheat, maize and sorghum grains were affected adversely at 25, 50 and 75% insect infestation caused by Trogoderma granarium Everts and Rhizopertha dominica Fabricius, separately and mixed population. R. dominica caused significant (P < 0.05) reduction in available carbohydrates at 50 and 75% infestation levels whereas T. granarium achieved similar effect at 75%. Mixture of both insect species caused intermediate losses. Storage of cereal grains up to 4 months resulted in substantial increase in sugars and decrease in starch content, but storage for a shorter period of time did not cause any significant changes in levels of carbohydrates.

Animals↗
PubMed1993

An improved dot ELISA to detect fowl adenovirus type-1 antigen.

An improved dot immunobinding assay to detect fowl adenovirus type-1 is described. The method consists of spotting of antigen on nitrocellulose membrane sheet, blocking with either 5% acetic acid or with 5% defatted milk powder and fixation of either antigen or antigen-antibody complex, with either 50% methanol or 0.25% glutaraldehyde or 0.2% tannic acid. The results revealed that fixation of both antigen and antigen-antibody complex resulted in 4-fold increase in sensitivity when acetic acid was used as blocking agent. The use of two substrates simultaneously resulted in more colour intensity and clarity than using both substrates separately.

Adenoviridae Infections↗
PubMed1993

Distribution of some elements in hydatid cysts of Echinococcus granulosus from buffalo (Bubalus bubalis).

Distribution of some elements during development of endogenous daughter (hydatid) cysts of Echinococcus granulosus of buffalo origin was determined by atomic absorption spectrophotometry. These analyses showed that the distribution of copper and cobalt was highest in the smallest cysts. These elements gradually decreased in the cysts as they enlarged. The distribution of zinc, iron and manganese was very high in the smallest cysts in comparison to copper and cobalt, but these three elements decreased greatly in larger cysts. Iron and manganese were the only two elements found in very high concentrations in "thin-walled" cysts. Like all other elements both calcium and magnesium decreased as the cysts increased in size. In the thin-walled cysts magnesium increased by four times initially and this was followed by a two-fold "influx" of calcium in the "white-spots" in the above cysts. The significance of these findings is discussed in relation to earlier works.

Animals↗
PubMed1993

Effect on mortality and reinfarction of adding fruits and vegetables to a prudent diet in the Indian experiment of infarct survival (IEIS).

The effects of antioxidant-rich foods as adjuncts to a prudent diet were compared for 12 weeks in a randomized, single-blind and controlled trial in 204 (group A) and 202 (group B) patients with acute myocardial infarction. There was a significant decrease in cardiac end points in group A compared to group B (37 vs 58, p < 0.01) after 12 weeks. Within intervention group A, those 108 patients with greater adherence to the intervention program showed a greater reduction in cardiac end points (14 vs 58, p < 0.001), and a significant decrease in total mortality (6 vs 28, p < 0.001), including cardiac mortality (6 vs 25, p < 0.01) compared to group B. Underlying these beneficial effects, antioxidant-rich foods caused a significantly smaller rise in lactate dehydrogenase (LDH) cardiac enzyme in group A than in group B (427.8 vs 561.6 IU/dL), indicating that the protective influence of such a diet may be observed within 1 week. The subset of group A patients showing reduction in mortality also had a lesser rise in LDH and greater reduction in blood lipids, blood glucose and blood pressures. Antioxidant-rich foods also caused a significant decrease in blood lipids with a lower decrease in high-density lipoprotein cholesterol in group A than in group B. Assay of serum level of antioxidants and long-term follow-up may confirm our observations.

Adult↗
PubMed1993

A mild form of mucolipidosis type III in four Baluch siblings.

Four Baluch siblings with mucolipidosis type III (pseudo-Hurler polydystrophy) are described. The patients had features commonly found in mucolipidosis III, including claw hands, joint stiffness, aortic valve involvement and radiological dysostosis multiplex. However, intelligence was normal, there were no eye abnormalities on slit-lamp examination and skin elasticity was normal. Many lysosomal enzymes were elevated in serum and diminished in cultured fibroblasts, although the findings for beta-galactosidase were atypical. Assays for the two enzymes involved in formation of the phosphomannose recognition marker revealed normal activity of the phosphotransferase with alpha-methylmannoside as an acceptor, and normal activity of the phosphodiester glycosidase. Metabolic labelling of fibroblasts with 32P followed by immunoprecipitation of cathepsin D, electrophoresis and fluorography showed that this enzyme was not labelled in the patients' cells, although some label was detected in the secreted precursor polypeptide. The data are consistent with the assumption that activity of the phosphotransferase is low towards lysosomal enzymes as substrates, and that the patients belong to complementation group C.

Arylsulfatases↗
PubMed1993

Aging, emotional states, and memory.

OBJECTIVE: This study compared the relation between negative mood states and memory in young and elderly subjects. METHOD: Forty-five normal, healthy young volunteers (ages 19-35 years) and 45 normal, healthy elderly volunteers (ages 60-78 years) were administered a verbal list-learning task and self-rated scales of affective states. RESULTS: The elderly group, but not the young group, consistently exhibited significant correlations between their performance on verbal recall measures and their ratings of their anxiety, depression, and withdrawal; i.e., within the elderly group, higher levels of negative affective states were associated with poorer memory. CONCLUSIONS: These findings indicate that aging modulates the relation between emotional state and memory functions, and they are consistent with the hypothesis that the elderly are more vulnerable than the young to the adverse effects of negative emotional states on memory. Therefore, even in normal elderly individuals without diagnosable psychopathology, negative affective states (such as anxiety and depression) may interfere with memory functioning.

Adult↗
PubMed1993

Effects of constant photoperiod-temperature regimes on testes and pituitary gonadotropic cells of the murrel, Channa punctatus (Bloch) during the annual reproductive cycle.

Mal Channa punctatus were maintained under constant photoperiod-warm temperature regimes (LD 16:8 and LD 8:16 at 30 degrees C) for one year. LD 16:8 regime stimulates testicular maturation and the activity of gonadotropic cells whereas LD 8:16 regime inhibits testicular maturation and also activity of gonadotropic cells. These results indicate a close correlation between the activity of gonadotropic cells and testes under long and short photoperiods at 30 degrees C regimes.

Animals↗
PubMed1993

Anthropometric and physiological profiles of active blind Malaysian males.

Cardiopulmonary capacities of twelve adults (aged between 14 to 44 years) with varying degrees of blindness engaged in regular recreational activities were compared with twelve age-matched normal sighted healthy males (control group) who were also involved in regular recreational activities. Maximum oxygen consumption (VO2max) was measured directly during exhaustive exercise test on a cycle ergometer. Forced vital capacity, leg strength and power were determined by spirometry, standing long jump and vertical jump respectively. No significant differences in VO2max, forced vital capacity and leg strength and power were observed between the blind and the control groups. No anthropometric differences were evident between the two groups. The results show therefore that the visually handicapped who are active can have a similar level of physical fitness, lung function and explosive leg strength as those of their active sighted counterparts.

Adolescent↗
PubMed1993

Photosynthetic carbon reduction cycle metabolites and enzymes of sucrose and starch biosynthesis in developing Brassica pods.

Rate of net CO2 exchange and activities of the key enzymes of fru-2,6-P2, sucrose and starch synthesis and levels of certain intermediates of Calvin cycle were determined in Brassica pods at different stages of their development. The rate of net CO2 exchange, activities of FBPase, UDPG-pyrophosphorylase and SPS, and the contents of 3-PGA, DHAP, RuBP and UDPG increased up to day 21 after anthesis followed by a continuous decrease thereafter. However the content of fru-6-P started decreasing only after 28 days of anthesis. Changes in the levels of fru-2,6-P2 were closely associated with the changes in F6P 2-kinase activity rather than with F2,6-P2ase activity. Similarly, activities of ADPG-pyrophosphorylase and ADPG-starch synthetase closely followed the pattern of starch accumulation in pod tissues. These observations suggest that during the early phase of pod development (up to 21 days after anthesis), which is also the active phase for pod photosynthesis, carbon is mainly utilised for sucrose synthesis and that during the later phase of pod development (from day 21 to 42 after anthesis), there is shift in metabolic path of carbon from sucrose to starch.

Brassica↗
PubMed1993

Informed decision making in persons acquitted not guilty by reason of insanity.

Deciding to raise an insanity defense carries serious consequences. This is especially true for persons charged with minor offenses, for whom an acquittal not guilty by reason of insanity (NGRI) might lead to a longer period of incarceration than would conviction. Before raising an insanity defense, a defendant should be provided with information necessary to make an informed decision and should be competent to understand the consequences of the verdict. This study attempted, through retrospective review and concurrent evaluation, to determine the degree to which trial courts in Virginia attended to these important aspects of informed decision making before finding defendants charged with misdemeanors NGRI. The study also attempted to assess the degree to which defendants were competent and informed at the time of adjudication. In most instances, trial courts did not consider defendants' competence to make decisions regarding the insanity defense and did not consider whether defendants were informed about the consequences of a successful insanity defense at the time of adjudication. The average length of stay for these patients was (at least) 21 months; most would have been released earlier had they been committed civilly rather than committed as a result of insanity pleas. We stress the need to educate judges, attorneys and forensic evaluators to the importance of considering defendants competence to plead insanity and of providing information about the consequences of a successful plea. We also propose that laws be changed to recognize the importance of these elements in the decision making process regarding pleas of insanity.

Adult↗
PubMed1993

Paederus dermatitis amongst medical students in USM, Kelantan.

We report a retrospective review of 12 medical students with a peculiar erythemato-vesicular dermatitis entomologically caused by an endemic beetle Paederus fuscipes. The clinical features, outcome in these cases and treatment are discussed. The students were residents of hostels in the USM campus in Kubang Kerian, Kelantan. The causative agent in all these cases were found to be Paederus fuscipes (rove beetle). The most common site of involvement in all these cases was the face, followed by the neck. The average duration of symptoms was two days and pruritus was a common symptom. About 83% of the patients made a complete recovery. However two patients (16%) had residual pigmentation.

Adult↗
PubMed1993

In vitro absorption of nutrients from small intestine of rats fed peroxidized oil.

Feeding of diet containing peroxidized oil (peroxide value approximately 90 mEq/kg) at 10% level for 4 weeks altered the absorptive function of intestine. Rate of in vitro absorption of nutrients especially sucrose and protein hydrolysate (amino acids) was considerably reduced. Absorption of glucose, fructose and Ca2+ was only marginally affected.

Animals↗
PubMed1993

Influence of pretreatment of carbamates on dynamic pulmonary mechanics in rats exposed to sarin aerosols.

The effect of pretreatment of two carbamates, pyridostigmine and physostigmine on dynamic pulmonary mechanics has been studied in rats exposed to sarin aerosols. Sign-free dose of pyridostigmine (0.075 mg/kg, i.m.) or physostigmine (0.1 mg/kg, i.m.) did not significantly alter the parameters of the dynamic pulmonary mechanics 20 min after treatment. However, sarin (51.2 mg/m3, for 15 min) depressed the respiratory rate, air flow and minute volume and enhanced the transthoracic pressure and tidal volume. Pretreatment with carbamates 20 min prior to sarin exposure significantly modified or counteracted the above induced changes. It is concluded that the protective effect of carbamates is mainly due to the correction of respiratory changes caused by sarin aerosols in rats.

Aerosols↗
PubMed1993

Sex hormones and diabetic retinopathy.

An estimation of the serum testosterone and follicle-stimulating hormone (FSH) levels using a radioimmunoassay technique was made in 25 control subjects, 52 diabetic patients without retinopathy, and six patients with diabetic retinopathy. Testosterone levels were higher in the diabetic patients with and without retinopathy than in the control subjects. They were significantly higher in the diabetic patients with retinopathy compared with the levels in those without retinopathy (P < .001) and equally significantly elevated compared with the levels in the control group (P < .001). Similarly, the FSH level was higher in the diabetic patients with retinopathy than in the control group and in those without retinopathy. Statistically, this increase was not significant (P > .05).

Adolescent↗