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Biomedical subjects

A K Mukherjee

Publications and source records attributed to A K Mukherjee.

At least 37 records · Page 2Linked to original sources
PubMed1999

Changes in the activity levels of glutamine synthetase, glutaminase and glycogen synthetase in rats subjected to hypoxic stress.

Exposure to high altitude causes loss of body mass and alterations in metabolic processes, especially carbohydrate and protein metabolism. The present study was conducted to elucidate the role of glutamine synthetase, glutaminase and glycogen synthetase under conditions of chronic intermittent hypoxia. Four groups, each consisting of 12 male albino rats (Wistar strain), were exposed to a simulated altitude of 7620 m in a hypobaric chamber for 6 h per day for 1, 7, 14 and 21 days, respectively. Blood haemoglobin, blood glucose, protein levels in the liver, muscle and plasma, glycogen content, and glutaminase, glutamine synthetase and glycogen synthetase activities in liver and muscle were determined in all groups of exposed and in a group of unexposed animals. Food intake and changes in body mass were also monitored. There was a significant reduction in body mass (28-30%) in hypoxia-exposed groups as compared to controls, with a corresponding decrease in food intake. There was rise in blood haemoglobin and plasma protein in response to acclimatization. Over a three-fold increase in liver glycogen content was observed following 1 day of hypoxic exposure (4.76 +/- 0.78 mg.g-1 wet tissue in normal unexposed rats; 15.82 +/- 2.30 mg.g-1 wet tissue in rats exposed to hypoxia for 1 day). This returned to normal in later stages of exposure. However, there was no change in glycogen synthetase activity except for a decrease in the 21-days hypoxia-exposed group. There was a slight increase in muscle glycogen content in the 1-day exposed group which declined significantly by 56.5, 50.6 and 42% following 7, 14, and 21 days of exposure, respectively. Muscle glycogen synthetase activity was also decreased following 21 days of exposure. There was an increase in glutaminase activity in the liver and muscle in the 7-, 14- and 21-day exposed groups. Glutamine synthetase activity was higher in the liver in 7- and 14-day exposed groups; this returned to normal following 21 days of exposure. Glutamine synthetase activity in muscle was significantly higher in the 14-day exposed group (4.32 mumol gamma-glutamyl hydroxamate formed.g protein-1.min-1) in comparison to normal (1.53 mumol gamma-glutamyl hydroxamate formed.g protein-1.min-1); this parameter had decreased by 40% following 21 days of exposure. These results suggest that since no dramatic changes in the levels of protein were observed in the muscle and liver, there is an alteration in glutaminase and glutamine synthetase activity in order to maintain nitrogen metabolism in the initial phase of hypoxic exposure.

Albinism↗
PubMed1998

Physico-chemical characterization of grain dust in storage air of Bangalore.

An Anderson personal cascade impactor was used to study the particle mass size distribution in the storage air of two major grain storage centers in Bangalore. Dust levels in storage air as well as the personal exposures of workers were determined along with a detailed study on the particle size distribution. Protein and carbohydrate content of the dust were also determined respectively in the phosphate buffer saline (PBS) and water extracts by using the standard analytical techniques. Personal exposures in both of the grain storage centers have been found to be much above the limit prescribed by ACGIH (1995-96). But the results of particle size analysis showed a higher particle mass distribution in the non-respirable size range. The mass median diameters (MMD) of the storage air particulate of both the centers were found to be beyond the respirable range. Presence of protein and carbohydrate in the storage air dust is indicative of the existence of glyco-proteins, mostly of membrane origin.

Air Pollutants, Occupational↗
PubMed1998

Effect of oral supplementation of vitamin E on the hemolysis and erythrocyte phospholipid-splitting action of cobra and viper venoms.

In the present investigation, it was found that oral supplementation of graded amounts of vitamin E to volunteers increased the alpha-tocopherol content of the erythrocytes and decreased the susceptibility of the latter to the hemolytic action of cobra and viper venoms. Further, exogenous addition of graded amounts of alpha-tocopherol to the red cells, prior to the addition of either venoms, minimizes the venom-induced lysis and erythrocyte phospholipid splitting. It may thus be inferred that vitamin E, a fat-soluble antioxidant, plays an important role in reducing the hemolytic action of cobra and viper venoms.

Animals↗
PubMed1998

The composition of Naja naja venom samples from three districts of West Bengal, India.

The variation in the composition of Naja naja venoms from three neighbouring districts of West Bengal, eastern India and the corresponding differences in the severity of pathogenesis due to venom composition variation are reported. These venom samples differ with respect to chromatographic elution profile and enzyme activity associated with each fraction. Presence of higher quantities of basic phospholipase and plasma protein hydrolase in the venom samples of Burdwan and Purulia make them more toxic than Midnapur venom sample. A polyvalent antivenom manufactured in western India was hardly effective in neutralizing the pathobiological manifestation of the venom samples from eastern India.

Animals↗
PubMed1997

Lysosomal membrane stabilization by alpha-tocopherol against the damaging action of Vipera russelli venom phospholipase A2.

This investigation shows the membrane stabilizing effect of alpha-tocopherol against the damaging action of viper venom phospholipase A2 (PLA2). Liver lysosomal membranes from rats fed 100 mg and 200 mg alpha-tocopherol acetate per kilogram of diet were more resistant to damage by viper venom PLA2 compared with vitamin E-deficient rats. The membrane stabilizing effect of vitamin E is proposed to be due to the formation of a complex with the phospholipid hydrolysis products of the membrane.

Animals↗
PubMed1996

Pollution and its control in asbestos milling processes in India.

An intervention study has been conducted in chrysotile asbestos milling processes with an interval of one year. The 'Membrane Filter Method' adopted in the former study for fiber concentration estimation has been followed in the present study, to estimate the environmental samples under the same experimental conditions. Though very high fiber levels compared to the prescribed permissible limit in India, have also been obtained in this study, a general reduction trend in the values of mills common to the both studies are observed. A further suitable control measure has been recommended in the paper to reduce fiber levels in the milling processes.

Air Pollution, Indoor↗
PubMed1994

Personality traits and performance of military parachutist trainees.

Fifty-two Indian military parachutist trainees were studied throughout the training period to investigate effects of stress in parachutist training on performance efficiency. Stress attributable to fear, anxiety, and apprehension about the inherent risk of paratrooping was studied along with physiological and biochemical changes. An attempt is made to correlate personality traits with performance efficiency. In cognitive and psychomotor tests, maximum deterioration was seen before the tower jump and aircraft jump. The deterioration was correlated with the level of anxiety and urinary catecholamine levels. Inter-correlations between anxiety, catecholamine, and blood pressure were positive, and the level of anxiety was seen to be affecting the quality of performance adversely.

Adult↗
PubMed1992

An environmental survey in chrysotile asbestos milling processes in India.

Environmental monitoring to determine airborne asbestos fiber levels has been carried out in four different mills processing chrysotile asbestos in the Cuddapah District (Andhra Pradesh) of India. The "membrane filter method" comprising standard asbestos sampling techniques, acetone-triacetin method for sample preparation, fiber counting, and sizing using the phase contrast optical microscope were adopted in the study. Fiber concentrations both with respect to personal exposures and processing areas were found in most of the cases to be much higher than the prescribed Threshold Limit Value (TLVs) of the developed and developing countries for chrysotile asbestos. By optical microscopy, fiber length distribution showed 70% of fibers in the milling processes were in size range > 5-10 microns, whereas in > 10-20 and > 20 microns, 20% and 8%, respectively. Fiber identification for major elemental content, also done by using scanning electron microscope equipped with an energy dispersive X-ray analyzer, indicated the presence of tremolite along with chrysotile. The study stresses the urgent need to adopt suitable engineering controls at the dust generating sources to reduce the fiber level in the mill environment below the threshold limit.

Air Pollutants, Occupational↗
PubMed1992

Evaluation of indirect immunofluorescent antibody test for detection of IgM specific antibodies in malaria.

Indirect immunofluorescent antibody test using Plasmodium falciparum antigen from in vitro culture was evaluated for detecting IgM antibodies in order to determine the feasibility of its application in serodiagnosis of malaria. Test was compared with the already adapted IgG-IIF test using the same antigen. It was found that none of the healthy controls and slide negative fever cases had malaria IgM antibodies whereas 8 per cent of healthy controls and 49.01 per cent of the slide negative fever cases had malaria IgG antibodies. The sensitivity of IgM-IIF test was 94.68 per cent and that of IgG-IIF test was 96.81 per cent. IgM antibodies could be detected very early even on the first day of fever and titre rose gradually with increasing number of days of illness before institution of treatment. The IgM antibodies, being short lasting are able to reflect recent infection. The test although highly sensitive and specific is laborious and expensive. Therefore, it may be used as a serodiagnostic test in advanced laboratories only for confirmation of selected slide negative cases.

Animals↗
PubMed1992

Detection of malaria antigen in blood by inhibition ELISA.

Demonstration of parasite associated antigen in blood by inhibition ELISA in malaria patients and controls is described. The test was negative in all the healthy controls and positive in 90 per cent of the Plasmodium vivax malaria cases. The test was found to be quite sensitive, being able to detect 5 parasites/10(6) RBC in a case of natural P. falciparum infection. There was 95.3 per cent agreement between the results of this test and IgM-IIF test.

Animals↗
PubMed1991

The completeness and accuracy of health authority and cancer registry records according to a study of ovarian neoplasms.

The completeness and accuracy of Hospital Activity Analysis (HAA) and Regional Cancer Registry (RCR) records were investigated in a series of 868 histologically reviewed cases in which primary ovarian neoplasms had been diagnosed according to one or more of seven data sources including HAA and RCR. All the women concerned were residents of Manchester and Salford who had presented in 1979-83 aged 15 years or more. The histological review confirmed the diagnosis of ovarian neoplasia in 829 of these women and excluded it in 39. Among the 829 confirmed cases, 333 were malignant or of borderline malignancy and therefore eligible for registration with the RCR, and 496 were benign. Only 611 (74%) of the 829 cases were listed as ovarian neoplasms or cysts in HAA records of hospital admissions from the study area during the study period, and the HAA diagnosis was incorrect in 40% of the 611 listed cases. Among the 333 borderline or malignant cases, only 241 (72%) appeared among the RCR's registrations of ovarian neoplasms for the study period and area. The RCR record of histological diagnosis was inaccurate in over 20% of these 241 registered cases, although most of the inaccuracies did not affect whether the neoplasm was classified as borderline or malignant. Five per cent of the cases listed as ovarian neoplasms in the HAA file and 15% of those listed as registrable ovarian neoplasms by the RCR should not have been so listed. The findings highlight the limitations of these routine health information systems, both as sources of cases for research and as National Health Service management tools.

Adolescent↗
PubMed1991

Effects of pyridoxine supplementation on blood glucocorticoids level, aspartate aminotransferase activity and glucose tolerance pattern under acute hypoxic stress.

Studies were conducted on male adult rabbits to find out the changes in blood glucocorticoid levels along with the changes in aspartate aminotransferase activity in blood and the role of pyridoxine on the glucose tolerance pattern under hypoxic stress. Hypoxic stress was produced by exposing the animals to a simulated altitude of 7,000 m for 6 h. In the first set of experiments 10 rabbits were used. Blood haemoglobin level, plasma and erythrocyte glucocorticoid levels and erythrocyte GOT activity were measured just before and after the exposure to hypoxia. Erythrocyte GOT activity was measured both without and with 50 mg of pyridoxal phosphate addition to the incubation mixture. Glucocorticoid levels in plasma increased by 11% whereas in erythrocytes the increase was 55% after hypoxia. Percent stimulation of erythrocyte GOT activity with pyridoxal phosphate before exposure to hypoxia was 180% but increased to 321% after exposure. In the second set of experiments another 10 rabbits were used. First they were exposed to hypoxia without pyridoxine hydrochloride feeding and then after 7 days with 3 mg of pyridoxine hydrochloride feeding. For glucose tolerance tests the animals were fed with 1 g of glucose immediately after the hypoxic exposures. Plasma reduced glutathione (GSH), LDH and ICDH activities increased and GOT activity was depressed after hypoxic stress, but when the animals were fed pyridoxine hydrochloride prior to the exposure the enzyme activities remained unaltered after hypoxic stress. Pyridoxine hydrochloride did not alter the pattern of glucose tolerance after hypoxic stress.

Animals↗
PubMed1991

Flexion osteotomy of the femur for genu recurvatum after poliomyelitis.

We report the results of 21 femoral osteotomies performed in 18 patients for genu recurvatum and flattening of the femoral condyles after poliomyelitis. Before operation the average angle of recurvatum was 31 degrees and all the limbs required bracing. After a mean follow-up of four years there has been partial recurrence in only one case. Nine patients (10 limbs) needed no orthosis and the others had less discomfort and an improved gait. Complete remodelling of the femoral and tibial epiphyses was noted in two of the younger patients.

Adolescent↗