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S Som

Publications and source records attributed to S Som.

28 records · Page 2Linked to original sources
PubMed1983

Ascorbic acid: a scavenger of superoxide radical.

The second order rate constant for the reaction between ascorbic acid and superoxide at pH 7.4 using the xanthine-xanthine oxidase system was estimated to be 5.4 x 10(6) M-1 sec-1. The results indicate that the efficacies of superoxide dismutase and ascorbic acid for catalyzing the decay of superoxide radical in animal tissues are similar. The significance of ascorbic acid as a scavenger of superoxide is discussed from the point of view of evolution of ascorbic acid synthesizing capacity in the terrestrial vertebrates.

Animals↗
PubMed1981

Interaction of mammalian hemoglobins with dehydroascorbic acid.

Reactive sulfhydryl groups of major hemoglobins from guinea-pig, rat and cat reduced dehydroascorbic acid to ascorbic acid leading to formation of intrachain disulfide bonds. Hybridization experiments indicated that the reduction was carried out by the alpha chain of cat hemoglobin.

Animals↗
PubMed1981

Ascorbic acid metabolism in diabetes mellitus.

In contrast to normal subjects diabetic patients and very low plasma ascorbic acid and significantly high (p less than 0.001) dehydroascorbic acid irrespective of age, sex, duration of the disease, type of treatment, and glycemic control. However, there was no significant difference between the mean leukocyte ascorbate concentrations of the two populations. The in vitro rates of dehydroascorbate reduction in the hemolysate and the erythrocyte reduced glutathione levels and the glucose-6-phosphate dehydrogenase activities, which regulate the dehydroascorbate reduction, were similar in normal and diabetic subjects. The turnover of ascorbic acid was higher in the diabetics than that in the normal volunteers. Experiments with diabetic rats indicated that the increased turnover of ascorbic acid was probably due to increased oxidation of ascorbate to dehydroascorbate in tissue mitochondria. Ascorbic acid supplementation at a dose of 500 mg per day for a brief period of 15 days resulted in an increase in the plasma ascorbate level temporarily, but it did not lower the blood glucose level of the diabetic patients.

Adolescent↗
PubMedDate not supplied

Climate and head form in India.

The relationship between head form and climatic variation was investigated in different tribal and caste populations of India. The magnitude of the cephalic index varies significantly in different zones. In tropical zones, head form is longer (dolicocephalic), but in temperate zones, head form is more round (mesocephalic or brachycephalic), especially among Scheduled Tribes (ST) and Scheduled Castes (SC) than among other castes. These trends possibly support a climatic adaptation model in head form differences among ST and SC in India.

Analysis of Variance↗