Search PubMed⌕ Search

Biomedical subjects

R Das

Publications and source records attributed to R Das.

At least 109 records · Page 6Linked to original sources

Activity and modulation of ornithine decarboxylase and concentrations of polyamines in various tissues of rats as a function of age.

The activities of ornithine decarboxylase (ODC) on the soluble and nuclear fractions of the cerebral cortex, heart and lungs of 4- (young), 38- (adult) and 85-week (old) male rats were studied. Also, the effects of aminophylline, histamine and estradiol on the activity of soluble ODC have been determined in vitro using slices of these tissues. The activity of ODC is significantly higher in the soluble fraction of all the tissues in comparison to that of nuclear fraction. Its activity in both the fractions is highest in the immature and decreases with increasing age in all the tissues except in the nuclear fraction of the lungs in which it increases with age. The ODC of the heart, lungs and cerebral cortex appear to be different as seen from the differences in their sensitivities to aminophylline, histamine and estradiol. In general, there is a decrease in its sensitivity to the three effectors with increasing age. This may be due to a decrease in the receptors and a concomitant decrease in ODC activity. A direct relationship between ODC activity and polyamine levels of the brain exists at various ages of the rat.

Aging↗

Role of thyroid gland on the peroxidase and iodinating enzymes of submaxillary gland.

The peroxidase (EC 1.11.1.7) and iodinase (EC 1.11.1.8) activities of rat submaxillary gland were found to be increased after thyroidectomy. The enzyme activities were maximal on the seventh day after operation and then decreased slightly. However, the enzyme activities were still more than 100% even 28 days following operation. Administration of thyroxine (10mug/100 g body weight) prevented the increase. Puromycin, cycloheximide, and actinomycin D, the inhibitors of protein synthesis, as well as thiouracil partially abolished the increase of activities. These results suggest that thyroxine acts as a regulator of the iodinase and peroxidase enzyme(s) of submaxillary gland,

Animals↗

Establishment of prenatal diagnosis for beta-thalassaemia: a step towards its control in a developing country.

Beta-thalassaemia constitutes a major health burden on the limited health resources of India and prenatal diagnosis is seen as an important preventive measure to reduce the burden of the disease. Prenatal diagnosis has been offered to 99 women in 112 pregnancies by fetal DNA analysis, using a PCR-based Amplification Refractory Mutation System (ARMS) for the common and uncommon Indian mutations. Restriction fragment length polymorphism (RFLP) for the beta-globin gene was used when the mutation remained unidentified in one of the parents or to complement the ARMS result. In 53 cases the fetus tested had beta-thalassaemia trait (betaTT) (47.3%), 22 were normal (19.6%) and 31 had thalassaemia major (27.6%). In five cases (4.5%), a definitive report could not be given due to maternal contamination. In one case (0.9%), there was a misdiagnosis. Pitfalls encountered in the diagnosis were maternal contamination and occasional non-amplification of the primers. Having established a regional centre for the prenatal diagnosis for thalassaemia, the screening programmes will be enlarged both to identify carriers and prevent the birth of further homozygous children, even during the first pregnancy.

DNA Mutational Analysis↗

Are Muslim women less susceptible to oncogenic human papillomavirus infection? A study from rural eastern India.

Muslim women are known to have lower incidences of cervical cancer and/or human papillomavirus (HPV) infection. Here we aim to determine any association that may be present between the oncogenic HPV16/18 infections and abnormal cytological lesions along with demographic and other attributes among Indian Muslim women (n = 478) and compare with the neighboring Hindus (n = 534) from a prospective cohort study. Agewise distribution of both subject-groups is similar. HPV16/18 infection is present in 9.6% Muslims and 7.5% Hindu women. Jointly atypical cells of undetermined significance (a typical cells of undetermined significance) and HPV16/18 are present in seven Muslim and two Hindu women. No high squamous intraepithelial lesions or cervical cancer is detected at the baseline. HPV16/18 infections show trends that varied with age, a nonlinear trend among Muslim women. In Hindu women the prevalence is highest at age < or =24 years, which linearly drops with increasing age. Abnormal cytology increases significantly in both religion-groups with increasing age. The data show that these Indian Muslim women are equally susceptible to HPV16/18 infection and for the development of abnormal cytology. There is a paucity in epidemiological data, which justifies the need to screen women of all religions for cervical cancer (that includes oncogenic HPV testing).

Adult↗