Search PubMed⌕ Search

Biomedical subjects

K Singh

Publications and source records attributed to K Singh.

At least 541 records · Page 30Linked to original sources
PubMed1986

Effect of some anthelmintics on malate dehydrogenase activity and mortality in two avian nematodes Ascaridia galli and Heterakis gallinae.

Cambendazole and tiabendazole at 10(-4) M concentrations caused mortality in both the parasites after 10 min and 20 min, respectively. H. gallinae was killed by 10(-4) M haloxon but A. galli remained alive even after 60 min exposure. The effect of these drugs was found to be irreversible since no resumption of activity was observed when the parasites were returned to normal saline solution. The ratio of oxaloacetate reduction to malate oxidation in the homogenates of A. galli and H. gallinae was 4.38:1 and 3.17:1 respectively. Cambendazole at 10(-3) M inhibited the enzymic activity in both directions by 100% in both A. galli and H. gallinae. 10(-3) M tiabendazole, however, inhibited the malate oxidation by 82.8 and 60.8% and oxaloacetate reduction by 76.6 and 92% in A. galli and H. gallinae, respectively. Haloxon had little effect on malate dehydrogenase activity of any of the parasite. Assay of malate dehydrogenase, following the in vitro drug treatment cambendazole and tiabendazole, exhibited moderate inhibition of the activity in both the parasites.

Animals↗
PubMed1985

Differential sensitivity to tributyltin of cytochrome-containing and cytochrome-deficient cells of Escherichia coli SASX76.

The effect of tributyltin (TBT) chloride on the growth of cytochrome-deficient and cytochrome-containing cells of Escherichia coli SASX76 was examined. The former cells were found to be at least 20 times more sensitive to TBT. It is proposed that the differential sensitivity of these two cell types to the biocide, TBT, may be due to a different mode of energy generation by cytochrome-deficient and cytochrome-sufficient cells. In addition to the energy state, the pH change caused by the presence and absence of cytochromes which occurred during growth also resulted in a differential sensitivity of these cells.

Adenosine Triphosphate↗
PubMed1985

Serial ultrasound in amoebic liver abscess.

Serial ultrasound examinations were conducted in 93 patients with amoebic liver abscess. The initial size of the abscesses ranged from 3 to 17 cm. The time taken for complete healing to occur varied from 10 to 300 days and correlated directly with the initial size of the abscess cavity. As healing progressed, the abscess cavity became increasingly hypoechoic and assumed a smoother margin. In uncomplicated cases, complete healing occurred and, on ultrasound, no residual lesions were seen in the liver. There were two cases each of delayed healing and recurrence of amoebic liver abscess and the value of ultrasound in these situations is discussed. Ultrasound examination of the liver appears to be very suitable for assessing satisfactory progress of healing in amoebic liver abscess.

Humans↗
PubMed1985

Resting heat production in Bos indicus and their F1 crosses with exotic breeds at a thermoneutral environment.

Resting heat production, 18 h post-feeding, was studied in Hariana cattle (Bos indicus; Zebu) and in their F1 crosses with Jersey, Brown Swiss and Holstein Friesian, at 18.5 degrees ambient temperature in a psychometric chamber at different ages. There was no significant change in the resting heat production on a per kg body-weight (W) 0.75 per 24 h basis from 16-19 to 37-40 months of age in any of the genetic groups. The daily resting heat production, however, increased with increases in body-weight and age. The resting heat production in all three F1 crosses was higher than that in Hariana cattle. Among the crosses, the resting heat production was highest in the Holstein Friesian X Hariana and lowest in the Jersey X Hariana. Metabolizable energy (ME) intake per 24 h was significantly different between genetic groups and in different age groups. However, ME intake per kg W 0.75 was not significantly different between genetic groups.

Aging↗
PubMed1985

Isolation of cellular genes differentially expressed in mouse NIH 3T3 cells and a simian virus 40-transformed derivative: growth-specific expression of VL30 genes.

We constructed and screened a cDNA library made from simian virus 40 (SV40)-transformed NIH 3T3 cells, and we isolated cDNAs representing genes that are differentially expressed between the parental cell and its SV40-transformed derivative. We found only a small number of cDNAs representing such genes. Two isolated cDNA clones represented RNAs expressed at elevated levels in the transformed cell line in a manner relatively independent of growth conditions. The expression of two other cDNAs was growth specific because transformed cells and nonconfluent parental cells contained higher levels of the homologous RNAs than did confluent, contact-inhibited parental cells. Another cDNA was well expressed in confluent parental and confluent transformed cells, but not in nonconfluent cells. The expression of some of these cDNAs varied strikingly in different mouse cell lines. Thus the genotype or histories of different cell lines can also affect the expression of certain genes. Interestingly, the only cDNA isolated that was expressed exclusively in the transformed cell was from an SV40 message. We focused on a growth-specific cDNA which we show is derived from a mouse endogenous retrovirus-like family called VL30. We sequenced the 3' long terminal repeat (LTR) of this transcriptionally active VL30 gene. This LTR has good homology with other VL30 LTR sequences, but differences occur, particularly upstream of the VL30 promoter. We found that VL30 gene expression varied in different mouse cell lines such that C3H cell lines had very low levels of VL30 transcripts relative to NIH 3T3 cell lines. However, Southern analysis showed that both cell lines had about the same number of VL30 genes homologous to our probe and that the position of the majority of these genes was conserved. We discuss possible explanations for this difference in VL30 expression.

Animals↗
PubMed1985

Cancer incidence in the islands of the Pacific.

The South Pacific Commission Cancer Registry has been operational since 1977, and reasonably complete cancer incidence rates are available for New Caledonia, Fiji, Micronesia, the Cook Islands, and Niue. In addition, less complete reporting is available from American Samoa, Papua New Guinea, and French Polynesia. Cancers of the lung, oral cavity, esophagus, liver, and cervix are potentially preventable but prevalent in many Pacific island countries. Unusually low rates of many cancers were observed in Fiji, the most notable being lung and colon-rectum. Thyroid cancer rates are elevated in some but not all female populations. These and other variations in cancer by site are important areas for further research.

Demography↗