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Biomedical subjects

M V Rao

Publications and source records attributed to M V Rao.

At least 73 records · Page 4Linked to original sources
PubMed1989

Interaction of antitumour agent mitoxantrone with poly[d(G-C)]--a circular dichroic study.

The binding of antitumour drug mitoxantrone [1,4-dihydroxy-5, 8-bis [2-(2-hydroxy ethyl)amino)ethyl)amino)-9, 10-anthracenedione] to the synthetic polynucleotide poly[d(G-C)] was studied by circular dichroic titrations. The interaction induced intense chiroptical properties in the visible (688 nm) as well as the ultraviolet (260, 320 nm) region in an otherwise optically inactive drug. The interaction occurs in two stages, one below a drug/nucleotide ratio of 0.11 and other above this value. The second mode of interaction causes an almost cooperative enhancement of the visible induced circular dichroism (ICD).

Circular Dichroism↗
PubMed1988

Estrogen induced effects on mouse testis and epididymal spermatozoa.

The effects of estradiol benzoate (E2B) at a dose of 200 micrograms/kg body weight/day for 7 and 15 days were investigated on epididymal sperm parameters and morphology of testis in adult mice. The data revealed a decline in cauda epididymal sperm count and percentage motility with duration of estrogen administration. The decreased sperm motility was correlated with reduced sperm enzymes as evidenced by biochemical and cytochemical studies. The depletion of cauda epididymal sperm population in treated mice was related to inhibition of spermatogenic activity in testis as compared to control. Thus, the estrogen treatment to mice manifests maturational changes in epididymal spermatozoa as a result of androgen deprivation.

Acid Phosphatase↗
PubMed1987

Theoretical study on binding of Hoechst 33258 with oligonucleotides.

Computer modelling with an energy minimization procedure is used here to obtain stereochemical and energetic details for complexes of the dye Hoechst 33258 with different oligonucleotide sequences. An optimised model of the dye with d(A)5 X d(T)5 is in conformity with previous proposed models. It has bifurcated hydrogen bonds between N2H and N4H of benzimidazole rings with N3 of adenine and O2 of thymine. Relative binding energies with different oligonucleotides show preference for AT containing sequences, with an intermediate affinity between that for netropsin and distamycin-2. Reduced binding is observed at high ionic concentration. The benzimidazole rings are twisted with respect to the phenol ring in the optimal model. This gives desired curvature to the molecule which is stabilised by intermolecular forces.

Benzimidazoles↗
PubMed1987

Differences in the response of early and mid or late G1 WI38 cells treated with cyclohexamide to HeLa inducers of DNA synthesis.

The inducibility of DNA synthesis after treatment with cyclohexamide (CHM) during mitosis and the G1 phase of WI38 cells has been studied in the heterokaryons following fusion with HeLa cells in S phase. Synchronized mitotic cells treated for up to 5 h with CHM were not delayed in the initiation of DNA synthesis in the heterokaryons. The G1 cells treated with CHM for 3-24 h were slow in responding to inducers of DNA synthesis generated by HeLa cells in the heterokaryons. The results suggest that there is a specific point in early G1 that regulates the entry of cells into a cycling state. In the presence of CHM, mitotic cells divide, but the daughter cells fail to enter G1 leading to DNA synthesis, and CHM treatment of G1 cells results in their transient entry into a G0 state.

Cell Cycle↗
PubMed1987

Hepatic and serum arginase and ornithine transcarbamylase activities of rats maintained on diets of different protein quality.

Groups of rats were fed diets containing 15% protein from arhar dal (Cajanus cajan), bengal gram dal (Cicer arietinum), urad dal (Phaseolus mungo) and also isolated proteins from casein, egg, soya bean, gluten and gelatin for a period of 10 days. Rats maintained on the casein diet had the highest liver arginase activity and those having egg the lowest. All the leguminous proteins gave similar levels of arginase activity, the values falling between the casein and egg groups. Serum arginase level was found to be low only in rats on egg and gluten diets. Liver ornithine transcarbamylase (OTC) activity was significantly higher when legumes provided the protein as compared with the diet containing egg. Serum OTC level was lowest in the egg and arhar dal groups. Though the levels of urea cycle enzymes were altered by the quality of dietary proteins, no simple relationship could be established between them.

Animals↗
PubMed1986

The exit of some human diploid fibroblasts (WI-38 cells) from the cell cycle in early G1.

The inducibility of DNA synthesis in WI-38 cells synchronized for different parts of G1 upon fusion with HeLa cells in S has been studied. In the heterokaryons 70 to 80% of WI-38 cell nuclei responded to HeLa inducers within one hour after cell fusion. The remainder of WI-38 cell nuclei responded to HeLa inducers after a lag of 3 hours or more. This lag was independent of duration of G1 traversed by WI-38 cells before cell fusion. The results of these studies suggest that 20 to 30% of WI-38 cells retire from the cell cycle in very early G1.

Cell Line↗
PubMed1986

Effect of estradiol benzoate on rat testis and adrenal.

The effects of in vivo administration of estradiol benzoate at a dose of 50 micrograms/rat/day for 15 days on testosterone production of testis and adrenal in vitro were investigated in rats. The data revealed that the androgen synthesis of both the steroidogenic organs were reduced by the treatment. The decrease in androgen production by testis was related to its reduced sperm count and weight. On the contrary, accumulation of cholesterol occurred in treated rat testis indicating inhibition of its steroidogenesis. This data confirm our earlier reports on the direct effect of estrogen on testis.

Adrenal Glands↗