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Biomedical subjects

A K Nandi

Publications and source records attributed to A K Nandi.

6 recordsLinked to original sources
PubMed1991

Generation of a nested series of interstitial deletions in yeast artificial chromosomes carrying human DNA.

We have generated a nested series of interstitial deletions in a fragment of human X chromosome-derived DNA cloned into a yeast artificial chromosome (YAC) vector. A yeast strain carrying the YAC was transformed with a linear recombination substrate containing at one end a sequence that is uniquely represented on the YAC and at the other end a truncated long interspersed repetitive element (LINE 1, or L1). Homologous recombination between the YAC and the input DNA resulted in a nested series of interstitial deletions, the largest of which was 500 kilobases. In combination with terminal deletions that can be generated through homologous recombination, the interstitial deletions are useful for mapping and studying gene structure-function relationships.

Chromosome Deletion↗
PubMed1990

Maternal mortality.

Maternal mortality in Chittaranjan Seva Sadan, Calcutta, in 1983, 1985 and 1986 was 2.45, 3.01 and 2.8 per thousand respectively. Abortion contributed a little in 1983 and 1985, whereas it was 15.7% in 1986. Haemorrhage was the commonest single cause of death in 1983 (28%) and 1985 (21.4%) as opposed to eclampsia in 1986 (28.9%). Infective hepatitis during pregnancy and labour was the commonest indirect cause of maternal mortality followed by anaemia. Usual difficulties like lack of antenatal care, multiparity, low socio-economical status, illiteracy, etc, in populated developing countries are responsible for this sad state of affairs in this country as well.

Female↗
PubMed1988

Regulated expression of genes inserted at the human chromosomal beta-globin locus by homologous recombination.

We have examined the effect of the site of integration on the expression of cloned genes introduced into cultured erythroid cells. Smithies et al. [Smithies, O., Gregg, R.G., Boggs, S.S., Koralewski, M.A. & Kucherlapati, R.S. (1985) Nature (London) 317, 230-234] reported the targeted integration of DNA into the human beta-globin locus on chromosome 11 in a mouse erythroleukemia-human cell hybrid. These hybrid cells can undergo erythroid differentiation leading to greatly increased mouse and human beta-globin synthesis. By transfection of these hybrid cells with a plasmid carrying a modified human beta-globin gene and a foreign gene composed of the coding sequence of the bacterial neomycin-resistance gene linked to simian virus 40 transcription signals (SVneo), cells were obtained in which the two genes are integrated at the beta-globin locus on human chromosome 11 or at random sites. When we examined the response of the integrated genes to cell differentiation, we found that the genes inserted at the beta-globin locus were induced during differentiation, whereas randomly positioned copies were not induced. Even the foreign SVneo gene was inducible when it had been integrated at the beta-globin locus. The results show that genes introduced at the beta-globin locus acquire some of the regulatory properties of globin genes during erythroid differentiation.

Animals↗