Search PubMed⌕ Search

Biomedical subjects

R Gupta

Publications and source records attributed to R Gupta.

At least 523 records · Page 29Linked to original sources
PubMed1994

Educational status, coronary heart disease, and coronary risk factor prevalence in a rural population of India.

OBJECTIVE: To define the association between educational level and prevalence of coronary heart disease and coronary risk factors in India. DESIGN: Total community cross sectional survey with a doctor administered questionnaire, physical examination, and electrocardiography. SETTING: A cluster of three villages in rural Rajasthan, western India. SUBJECTS: 3148 residents aged over 20 (1982 men, 1166 women) divided into various groups according to years of formal schooling. RESULTS: Illiteracy and low educational levels were associated with less prestigious occupations (agricultural and farm labouring) and inferior housing. There was an inverse correlation of educational level with age (rank correlation: mean -0.45, women -0.49). The prevalence of coronary heart disease (diagnosed by electrocardiography) was significantly higher among uneducated and less educated people and showed an inverse relation with education in both sexes. Among uneducated and less educated people there was a higher prevalence of the coronary risk factors smoking and hypertension. Educational level showed a significant inverse correlation with systolic and diastolic blood pressure. Logistic regression analysis with adjustment for age showed that educational level had an inverse relation with prevalence of electrocardiographically diagnosed coronary heart disease (odds ratio: men 0.82, women 0.53), hypertension (men 0.88, women 0.56), and smoking (men 0.73, women 0.65) but not with hypercholesterolaemia and obesity. The inverse relation of coronary heart disease with educational level abated after adjustment for smoking, physical activity, body mass index, and blood pressure (odds ratio: men 0.98, women 0.78). CONCLUSION: Uneducated and less educated people in rural India have a higher prevalence of coronary heart disease and of the coronary risk factors smoking and hypertension.

Adult↗
PubMed1994

Hybrid molecules containing propargylic sulfones and DNA minor groove-binding lexitropsins: synthesis, sequence specificity of reaction with DNA and biological evaluation.

A series of hybrids, 4-13, incorporating propargylic sulfones and minor groove-binding oligopeptide carriers, was synthesized. The anticipated preferential binding at adenine sites within the minor groove was confirmed by sequencing determination of these agents on high-resolution gels, indicating preferential alkylation at guanine, and significantly, high selectivity for 5'-GACG and 5'-GGTG. The ability of these hybrids to cleave DNA, as determined by agarose-gel assay, is consistent with the ethidium bromide fluorescence assay. The cytotoxicities of these compounds were also determined against human KB cells in vitro. Higher cytotoxic activities were observed for the compounds containing fewer N-methylpyrrole units, an imidazole group and a 2,3-disubstituted naphthyl moiety.

1-Propanol↗
PubMed1994

Effect of interleukin-1 alpha on the growth of Mycobacterium microti within J774A.1 cells.

The effect of mouse recombinant interleukin-1 alpha on the intracellular growth of Mycobacterium microti in a murine macrophage cell line J774A.1 was investigated. Interleukin-1 alpha added after infection to the M. microti-infected macrophage monolayers enhanced the growth of M. microti in a concentration-dependent manner and this growth enhancement was abrogated by neutralization of interleukin-1 alpha with anti-interleukin-1 alpha antibody. Cyclic adenosine monophosphate level in J774A.1 cells was increased by the addition of interleukin-1 alpha. Addition of dibutyryl cyclic adenosine monophosphate to infected J774A.1 cells increased the number of intracellular bacteria in a concentration-dependent manner. These results suggest that interleukin-1 alpha acts as a growth enhancer for intracellular M. microti and the growth enhancing effect of interleukin-1 alpha may be due to enhanced cellular cyclic adenosine monophosphate level.

Animals↗
PubMed1994

Rock phosphate solubilization under alkaline conditions by Aspergillus japonicus and A. foetidus.

Aspergillus japonicus and A. foetidus were found to solubilize five types of Indian rock phosphates at pH 8 and 9. Solubilization was higher in the presence of pyrite than in controls lacking either pyrite or fungal inoculum. Both the aspergilli were found to be good pyrite solubilizers and could grow over a wide pH range. Solubilization of rock phosphates was the result of organic acid release and pyrite oxidation.

Aspergillus↗
PubMed1994

Persistence of cell-mediated and humoral immune responses in healthy children immunized with live attenuated varicella vaccine.

Two hundred fourteen healthy seronegative children immunized with various doses of Oka/Merck varicella vaccine were studied for persistence of varicella-zoster virus (VZV)-specific lymphocyte proliferation and antibodies to VZV as determined by a glycoprotein (gp) ELISA. Of the 140 vaccinees tested for VZV-specific lymphocyte proliferation, 94% had positive responses, with a mean stimulation index of 8.9 (range, 3.0-44.6). Of 214 tested by gpELISA, 95% were positive for up to 6 years after immunization; the geometric mean titer was 30.2 (range, 1.3-3510.0). Of 122 individuals tested both by ELISA and for VZV-specific lymphocyte proliferation, 91% had persistence of both responses. Persistence of cellular and humoral immune responses in a large percentage of vaccinees for up to 6 years after immunization with Oka/Merck varicella vaccine suggests that protection against severe varicella is likely to be similarly long-lasting.

Adolescent↗
PubMed1994

Cushing's disease: pituitary imaging.

Fourteen patients with adrenocorticotropic hormone (ACTH)-dependent hypercortisolism underwent pituitary scanning with computed axial tomography (CT) and magnetic resonance imaging (MRI). Computed tomography revealed pituitary macroadenomas in two patients, pituitary hyperplasia in one and a suspicion of pituitary microadenoma in one. Thirteen patients underwent MRI. One with a macroadenoma diagnosed on CT did not undergo MRI. The MRI revealed a pituitary macroadenoma in one, microadenoma in three and hyperplasia in two cases. Magnetic resonance imaging following gadolinium diethylene triamine penta acetic acid (gd-DTPA) enhancement revealed four more pituitary microadenomas. All patients who had pituitary adenomas (micro and macro) and hyperplasia underwent trans-sphenoidal pituitary surgery. One of the two patients, who had an enlarged pituitary on imaging but no demonstrable adenoma, was found to have a microadenoma at surgery. Patients with ACTH-dependent hypercortisolism should undergo MRI of the pituitary gland to identify/localize corticotroph pituitary adenomas. The study should include gd-DTPA enhancement in cases where the scan is normal.

Adenoma↗
PubMed1994

A new method for the estimation of the components of energy expenditure in patients with major trauma.

The management of critically ill patients would be better understood if the total energy expenditure (TEE) and its components are known. To quantify the different components of energy expenditure in patients with major trauma, we used a technique combining measurements of body composition and oxygen consumption. We determined changes in body weight, total body water, total body protein, total body potassium, total body fat, and bone mineral content every 5 days over a 10-day period in a group of nine multiply injured patients. Resting energy expenditure was measured by indirect calorimetry (REEm), and a predicted value was obtained from total body potassium (REEp). TEE was assessed by adding the total calorie intake to the changes in body energy stores, and the activity energy expenditure (AEE) was calculated by subtracting REEm from TEE. Mean daily values for REEm, REEp, TEE, and AEE were 2,236 +/- 140, 1,683 +/- 82, 3,029 +/- 276, and 793 +/- 213 kcal/day, respectively, over the 10-day study period. Although not statistically significant, the mean AEE was four times smaller for the first 5 days of study than for the second 5 days (298 +/- 400 vs. 1,254 +/- 588 kcal/day). The technique of combining indirect calorimetry and body composition measurements offers a new approach to evaluate energy expenditure and a new way to study metabolic disorders and therapeutic strategies in critically ill patients.

Adolescent↗
PubMed1994

Exercise-induced pulmonary vasoconstriction during combined blockade of nitric oxide synthase and beta adrenergic receptors.

We studied the effects of inhibition of nitric oxide (NO) (endothelium-derived relaxation factor) synthase in combination with alpha and beta adrenergic receptor blockade on pulmonary vascular tone during exercise. In paired studies, we exercised sheep on a treadmill at a speed of 4 mph, and measured blood flow and pressures across the pulmonary circulation with and without inhibition of NO synthase (N omega-nitro-L-arginine 20 mg/kg intravenous [i.v.]), alpha receptor blockade (phentolamine 5 mg i.v.), beta receptor blockade (propranolol 1 mg i.v.), and combined alpha and beta receptor blockade. Activation of both types of adrenergic receptors occurs with exercise, and because increased release in NO is hypothesized to occur during exercise, these studies were designed to determine the magnitude of effect and interactions of these competing dilator and constrictor influences. We found that inhibition of NO synthase raised pulmonary vascular resistance (PVR) at rest and that, although a reduction in PVR occurred with exercise from this new baseline, vasoconstriction persisted. Combined beta blockade and NO synthase inhibition unmasked unopposed alpha vasoconstriction; PVR rose at rest and continued to rise with exercise; and mean pulmonary arterial pressures approached very high levels, 43.8 +/- 4.4 cmH2O. Using a distal wedged pulmonary artery catheter technique, most of the vasoconstriction was found to be in vessels upstream from small pulmonary veins. During exercise in sheep there appears to be a high degree of alpha and beta adrenergic-mediated tone in the pulmonary circulation. Endogenous production of NO actively dilates pulmonary vessels at rest and opposes potent alpha-mediated pulmonary vasoconstriction during exercise.

Amino Acid Oxidoreductases↗
PubMed1994

Changes in pulmonary vascular tone during exercise. Effects of nitric oxide (NO) synthase inhibition, L-arginine infusion, and NO inhalation.

Nitric oxide (NO) is a potent endogenous vasodilator. Its role in the normal and stressed pulmonary circulation is unclear. To better understand the importance of endogenous NO in normal physiological responses, we studied the effects of altered NO availability on the change in pulmonary vascular tone that accompanies exercise. In paired studies we measured blood flow and pressures in the pulmonary circulation at rest and during treadmill exercise at a speed of 4 mph with and without (a) N omega-nitro-L-arginine, 20 mg/kg intravenously, a selective inhibitor of NO synthase; (b) L-arginine, 200 mg/kg intravenously, substrate for NO synthase; (c) combination of the inhibitor and substrate; and (d) inhalation of NO > 30 ppm, to determine if endogenous release of NO elicits maximal vasodilation. In addition, we sought to determine the site of NO effect in the pulmonary circulation by preconstriction with either U-44619 or hypoxia (fraction of inspired O2 = 0.12) using a distal wedged pulmonary catheter technique. NO synthase inhibition raised pulmonary vascular tone equally at rest and exercise. L-Arginine reversed the effects of NO synthase inhibition but had no independent effect. NO inhalation did not reduce pulmonary vascular tone at rest or enhance the usual reduction in pulmonary vascular resistance with exercise. The effect of NO synthase inhibition was in pulmonary vessels upstream from small veins, suggesting that endogenous NO dilates primarily small arteries and veins at rest. We conclude that, in sheep, endogenous NO has a basal vasodilator function that persists during, but is not enhanced by, exercise.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1994

Lipoprotein lipids and the prevalence of hyperlipidaemia in rural India.

BACKGROUND: The prevalence of hyperlipidaemias has been inadequately studied in rural populations of developing countries. No significant data exist on the population levels of serum cholesterol, cholesterol subclasses or triglycerides in these countries. METHODS: We studied fasting blood samples of 300 apparently healthy adults (202 men and 98 women, age range 20-73 years) randomly selected from a larger sample of 3148 individuals during a comprehensive cardiovascular risk-factor survey in Rajasthan, India. Levels of serum total cholesterol, its subfractions [low-density-lipoprotein (LDL) cholesterol, very-low-density-lipoprotein cholesterol and high-density-lipoprotein (HDL) cholesterol] and triglycerides were measured and correlated with age and anthropometric data. RESULTS: The mean +/- SD serum total-cholesterol levels were 4.39 +/- 1.0 mmol/l in men and 4.37 +/- 1.0 mmol/l in women, the mean LDL-cholesterol levels 2.51 +/- 1.0 mmol/l in men and 2.62 +/- 0.9 mmol/l in women, the mean HDL-cholesterol levels 1.15 +/- 0.4 mmol/l in both mean and women and the mean fasting serum triglyceride levels 1.63 +/- 0.6 mmol/l in men and 1.48 +/- 0.7 mmol/l in women. Age correlated positively with total-cholesterol, LDL-cholesterol, HDL-cholesterol and triglyceride levels in both men and women. Levels of the cholesterol subtypes did not differ between the sexes (P > 0.01), although triglyceride levels were significantly higher in men (P < 0.01). Lipoprotein lipids did not correlate significantly with height, weight, body-mass index or waist:hip ratio. When classified according to the recommendations of the US National Cholesterol Education Program for the determination of the prevalence of hyperlipidaemia, 43 individuals (14.3%; men 14.4% and women 14.3%) had borderline high cholesterol levels (5.20-6.18 mmol/l) and 24 (8%; men 7.9% and women 8.2%) had high cholesterol levels (> or = 6.21 mmol/l). Forty-five participants (15%) had borderline high LDL-cholesterol levels (3.36-4.11 mmol/l) and 20 (6.7%) had high LDL-cholesterol levels (> or = 4.14 mmol/l); low HDL-cholesterol levels (< 0.9 mmol/L) were found in 89 (29.7%). Eighteen participants (6%) had mild hypertriglyceridaemia (2.82-5.64 mmol/l) and two (0.7%) had severe hypertriglyceridaemia (> 5.64 mmol/l). CONCLUSION: Total-cholesterol and LDL-cholesterol levels are low in a rural Indian population, although an atherogenic lipid profile is present in a significant proportion.

Adult↗
PubMed1994

Insulin-like growth factor-I and insulin have no differential effects on glucose production and utilization under conditions of hyperglycemia.

We have previously shown that in moderately hyperglycemic depancreatized dogs, a glucose-lowering infusion of insulin-like growth factor-I (IGF-I) increased glucose utilization and lactate more, and suppressed glucose production and lipolysis less, than an equipotent glucose-lowering dose of insulin. Similar differences have been observed by others in nondiabetic and diabetic rats. To determine whether the decline in glycemia was important in detecting differential effects of IGF-I and insulin on glucose turnover, IGF-I (0.43 micrograms/kg.min; n = 6) or insulin (0.9 mU/kg.min; n = 9) were infused for 180 min, while hyperglycemia (approximately 180 mg/dl) was maintained. The decline of plasma glucose specific activity was minimized by using the matched step tracer infusion ([6-3H]- and [2-3H]glucose) method. Our results confirmed the approximately 10% potency of IGF-I on glucose metabolism compared to insulin and the lack of effect of IGF-I on insulin clearance. Under conditions of hyperglycemia, the glucose turnover findings were unexpected; there was no difference in the inhibition of glucose production (difference from basal, 2.7 +/- 0.4 mg/kg.min with IGF-I and 2.4 +/- 0.2 with insulin) or the stimulation of glucose utilization (difference from basal, 4.5 +/- 0.8 mg/kg.min with IGF-I and 4.7 +/- 1.3 with insulin). However, lactate increased more (P < 0.01) with IGF-I (from 1230 +/- 163 to a peak of 1903 +/- 349 microM) than insulin (from 1209 +/- 291 to 1535 +/- 340 microM) despite the same increment in glucose utilization. FFA and glycerol declined more with insulin, but the difference was not significant. IGF-I and insulin suppressed plasma amino acids to an equivalent extent. We concluded that 1) the differential effects of IGF-I and insulin on glucose turnover are masked under conditions of hyperglycemia; and 2) because insulin and IGF-I induced the same increment in glucose utilization, but lactate increased more with IGF-I, IGF-I might affect intracellular glucose metabolism differently from insulin. The failure of IGF-I to induce greater glucose utilization than insulin during hyperglycemia, the greater rise in lactate with IGF-I treatment, and the absence of differential effects on proteolysis indicate that IGF-I might have only limited clinical application in the treatment of diabetes.

Animals↗
PubMed1994

A technique for assessing the effects of pH and photodegradation on the stability of the iron chelate of ethyl N-methyl-4-hydroxy-5-oxo-3-pyrroline-3-carboxylate.

Ethyl N-methyl-4-hydroxy-5-oxo-3-pyrroline-3-carboxylate forms a deep red chelate with iron salts. The color intensity is directly related to the iron concentration. The photostability of the red color was determined at pH 1.2 and 5 by spectrophotometric assay at 484 nm at intervals during irradiation by tungsten light at 1020 microW/cm2. After 528 hr of continuous irradiation in deionized water, 90.9% of the iron chelate had decomposed. The reaction followed zero order kinetics. Maximal stability was observed at pH 5 at both 10(-1) and 10(-2) molar concentrations of the iron chelate; no detectable decomposition occurred after 192 hr of continuous irradiation. The iron chelate in biological tissues is stable for 18 months. The staining technique is superior to other histological methods for estimating low concentrations of iron in tissue.

Chlorides↗