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Biomedical subjects

S K Roy

Publications and source records attributed to S K Roy.

At least 181 records · Page 10Linked to original sources
PubMed1984

Characterization of anti-N-acetyl-D-glucosamine antibodies elicited through haptenated liposomes.

Antiserum was raised in rabbits against p-aminophenyl 2-acetamido-2-deoxy-beta-D-glucoside covalently coupled to phosphatidylaminoethanol-containing lecithin liposomes. The affinity-purified antibodies were found to be IgM. The properties of the antibodies were studied by ligand inhibition of quantitative precipitation, fluorescence titration with 2-acetamido-2-deoxy-D-glucose, and complement lysis of haptenated liposomes.

Acetylglucosamine↗
PubMed1984

Isolation of Yersinia enterocolitica and Y. intermedia from fatal cases of diarrhoeal illness in Bangladesh.

From three fatal cases of diarrhoeal illness in Bangladesh, Yersinia species were isolated from tissues at post-mortem examination. One patient was infected with Y. enterocolitica serotype 0:7, 8 and two patients were infected with Y. intermedia. These patients were infected also with other enteric pathogens. These findings suggest that Yersinia may be important as pathogens in tropical diarrhoea and as co-pathogens in serious disease.

Adult↗
PubMed1984

Species differences in levonorgestrel binding to serum proteins of monkey, rabbit and rat blood.

Levonorgestrel binding to serum proteins of monkey, rabbit and rat was studied. It showed high affinity binding to monkey and rabbit serum proteins but not to rat serum. Characterization by polyacrylamide gel electrophoresis revealed that the binding of levonorgestrel occurs to sex hormone binding globulin (SHBG) and albumin, but in rat it is confined to albumin only. These results suggest species differences in levonorgestrel binding to serum proteins and extrapolation of data from one animal model to another may not be directly feasible.

Animals↗
PubMed1984

Induction of implantation in rats by a nonsteroidal antifertility agent, 1,2-diethyl-1,3-bis(p-methoxyphenyl)-1-propene.

A nonsteroidal antifertility agent 1,2-diethyl-1,3-bis(p-methoxyphenyl)-1-propene has been investigated to assess its capacity to induce implantation in delayed rats. The administration of the compound successfully induced the implantation in all rats. We have concluded that the process of induction of implantation in such rats may be due to a frank estrogenic action of the compound. Furthermore, the use of the compound as a new oral substitute for diethylstilbestrol is suggested.

Animals↗
PubMed1984

Oral rehydration solution safely used in breast-fed children without additional water.

Sixty-four children of age 3 months to 2 years were treated for diarrhoea in a rural treatment centre with oral rehydration solution (90 mmol/l Na+); plain water was not supplied during rehydration. All children continued breast-feeding during the therapy. Serum sodium levels after 24 h of intake indicated that 61 children had serum sodium level below 148 mmol/l and three were above (range 150-151). None of the children developed clinical signs or symptoms of hypernatremia. The use of additional water may not be necessary during rehydration therapy of breast-fed children.

Breast Feeding↗
PubMed1983

Excess mortality among children discharged from hospital after treatment for diarrhoea in rural Bangladesh.

Five hundred and fifty one children aged between 3 months and 3 years were followed up at home for 12 months after treatment of diarrhoea in a rural treatment centre of the International Centre for Diarrhoeal Disease Research, Bangladesh. During follow up the children were found to have a significantly higher mortality than generally observed in the community. The first three months after discharge appeared to be crucial, some 70% of the deaths occurring in that period. Severely malnourished children (nutritional state below 56% of the American National Center for Health Statistics (NCHS) standard of weight for age ratio) had a risk of death 14 times that of their well nourished counterparts (nutritional state 66% or more of the NCHS standard). The highest mortality occurred in 2 year olds, one in three of the severely malnourished children dying compared with one in 10 of the moderately malnourished. This pattern was not seen in children aged under 2 years. Immediate priority should be given to providing nutritional rehabilitation for malnourished children who contract diarrhoea.

Age Factors↗
PubMed1983

Histochemical study of beta-glucuronidase in the rat uterus during implantation and pseudopregnancy.

On Day 5 of pregnancy and pseudopregnancy, beta-glucuronidase activity in pseudopregnant uteri and in the inter-implantation zones from pregnant animals was found mainly in stromal and glandular epithelial cells. The luminal epithelium also showed an intense enzyme-positive reaction, particularly in the apical regions of these cells. Blastocyst attachment was associated with marked depletion of beta-glucuronidase activity from epithelial cells lying adjacent to the blastocyst, suggesting a possible involvement of this lysosomal enzyme in the blastocyst-endometrium attachment reaction.

Animals↗
PubMed1982

In vitro inhibiton of trophoblast maturation and expansion of early rat blastocysts by an oestrogen antagonist.

Rat blastocyst development and expansion were studied in an in vitro culture system. Early blastocysts collected from rats on the morning of day 5 were shown to develop normally and underwent expansion when placed in bovine serum albumin supplemented culture medium for 12 h at 37 degrees C. Nafoxidine, an oestrogen antagonist, prevented embryo expansion when added to the culture medium, and it was found that if oestradiol-17 beta was added to this medium this inhibitory effect was removed and the embryos again expanded. Ethanol, used as a solvent for steroids, and cholesterol were added to the medium containing nafoxidine but the blastocysts remained unexpanded after 12 h in culture. These results suggest a need for oestrogen action during blastocyst expansion in vitro. Cultured rat blastocysts were subjected to histochemical study for acid phosphatase (ACPase) and leucylnaphthylamidase (LNAse). In unexpanded blastocysts ACPase was found to be low while LNAse activity was higher when compared with enzyme distribution patterns in expanded blastocysts.

Acid Phosphatase↗
PubMed1982

Isolation of bacteria producing chloramphenicol acetyltransferase from soil and their characterization.

After screening 107 soil samples collected from different spots around Calcutta, 579 chloramphenicol resistant colonies were isolated. Out of these only 58 colonies could inactivate chloramphenicol in detectable amounts. By noting the production of inactivating factor, 5 high yielding strains were further characterized to species level. Three of them were Escherichia coli strains, the two others were Alcaligenes faecalis and Klebsiella pneumoniae strains. All strains inactivated chloramphenicol by acetylation, with the production of chloramphenicol acetyltransferase. Production of this latter enzyme was not inducible. Minimum inhibitory concentrations for these 5 strains were studied against 14 antimicrobial agents. All strains were found to be resistant to most antimicrobial agents, but sensitive to polymyxin B. The strain A. faecalis was also sensitive to carbenicillin but other four strains were resistant to this antibiotic.

Acetyltransferases↗
PubMed1981

Rat embryo development in vitro.

We report the first successful culture of 8-cell/morula stage rat embryos in a fully synthetic medium supplemented with 3% crystalline bovine serum albumin. Eighty-four per cent of morulae developed to blastocysts, showing that this is a highly efficient culture medium for in vitro studies on rat pre-implantation embryos. Blastocyst formation was severely inhibited by antioestrogen (nafoxidine 3 microgram/ml) but no further reversal was obtained by giving oestrogen to culture medium containing this antagonist.

Animals↗
PubMed1981

Effect of an anti-oestrogen on implantation of mouse blastocysts.

Mouse blastocysts collected on Day 4 were cultured for 4 h in Whitten's medium containing 5 micrograms CI-628 citrate, a specific oestrogen antagonist, and transferred to the uteri of pseudopregnant hosts. There was a significant reduction in the number of implantations observed on Day 11 when compared with those from blastocysts which were similarly transferred after culture in medium alone or in medium containing 1 microgram oestradiol-17 beta and 5 micrograms CI-628 citrate. We suggest that this is further evidence for the involvement of embryonic oestrogen in implantation.

Animals↗
PubMed1981

Studies on progesterone receptors during protein malnutrition and steroid maintained pregnancy in rat.

The distribution pattern of progesterone receptors (PR) in nuclear and cytoplasmic compartments of uterus and factors affecting the PR levels were studied. The concentration of nuclear PR was decreased significantly on day 15 and 20 of dietary protein restriction, both in non-mated and mated rats. However, a marked decline in cytosol PR levels was observed only in non-mated protein-free diet (PFD) rats. During steroid-maintained pregnancy the concentration of PR in uterine nuclei was significantly higher on day 15 of gestation than those obtained on day 20. In contrast, the levels of PR in cytosol, were much higher on day 20 of gestation in steroid maintained as well as normal pregnant rats. The translocation studies revealed that the magnitude of translocated PR complex to the nucleus (at 3 h) was more pronounced in protein deficient rats and the time-dependent replenishment of cytosol PR was not observed in above group, as proposed for estrogen receptors. Administration of estradiol 17-beta to PFD-rats resulted in an increase in cytosol PR without altering the nuclear PR levels. In addition, protein deficient rats exhibited a higher Kd value than normally fed rats. In conclusion, it can be suggested that these fluctuations in uterine PR are related to changes in endogenous hormone levels and binding affinity of receptor molecules.

Animals↗