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111.
112.
Elucidation of defense‐related signaling responses to spot blotch infection in bread wheat (Triticum aestivum L.) 下载免费PDF全文
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M. Dutta V. Arunachalam A. Bandyopadhyay 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,74(4):466-470
Summary Six groundnut genotypes belonging to the Virginia and Valencia sub-groups were irradiated with gamma rays at doses of 5, 10, 15 and 20 kR, much below LD50, and grown surrounded by a pollen parent in a split-plot design. The succeeding two generations were checked for the occurrence of hybrids by examining the segregation for pod and seed characteristics and the two quantitative characters, pod and seed yield. Cross-pollination up to 20.8% was observed in M13, a Virginia cultivar. There was a genotype-dose interaction for the extent of cross-pollination. Cross-pollination was higher in Virginia than Valencia genotypes and more frequent under 15 and 20 kR than under other doses, in general. The observed substantial enhancement of cross-pollination encourages the use of seed irradiation at proper doses as a method for increasing recombination in plant breeding programmes. 相似文献
115.
In vitro infection of natural killer cells with different human immunodeficiency virus type 1 isolates. 总被引:10,自引:0,他引:10 下载免费PDF全文
J Chehimi S Bandyopadhyay K Prakash B Perussia N F Hassan H Kawashima D Campbell J Kornbluth S E Starr 《Journal of virology》1991,65(4):1812-1822
Natural killer (NK) cells are a discrete subset of leukocytes, distinct from T and B lymphocytes. NK cells mediate spontaneous non-MHC-restricted killing of a wide variety of target cells without prior sensitization and appear to be involved in initial protection against certain viral infections. Depressed NK cell-mediated cytotoxicity, one of the many immunological defects observed in AIDS patients, may contribute to secondary virus infections. Here we report that clonal and purified polyclonal populations of NK cells, which expressed neither surface CD4 nor CD4 mRNA, were susceptible to infection with various isolates of human immunodeficiency virus type 1 (HIV-1). Viral replication was demonstrated by detection of p24 antigen intracellularly and in culture supernatants, by the presence of HIV DNA within infected cells, and by the ability of supernatants derived from HIV-infected NK cells to infect peripheral blood mononuclear cells or CD4+ cell lines. Infection of NK cells was not blocked by anti-CD4 or anti-Fc gamma RIII monoclonal antibodies. NK cells from HIV-infected and uninfected cultures were similar in their ability to lyse three different target cells. Considerable numbers of cells died in HIV-infected NK cell cultures. These results suggest that loss of NK cells in AIDS patients is a direct effect of HIV infection but that reduced NK cell function involves another mechanism. The possibility that NK cells serve as a potential reservoir for HIV-1 must be considered. 相似文献
116.
Tanya Das Gaurisankar Sa Anup K Bandyopadhyay Manju Mukherjea 《Journal of biosciences》1991,16(4):235-242
The relationship between fatty acid binding proteins, ATP citrate lyase activity and fatty acid synthesis in developing human
placenta has been studied. Fatty acid binding proteins reverse the inhibitory efect of palmitoyl-CoA and oleate on ATP citrate
lyase and fatty acid synthesis. In the absence of these inhibitors fatty acid binding proteins activate ATP citrate lyase
and stimulate [ 1-14 C] acetate incorporation into placental fatty acids indicating binding of endogenous inhibitors by these proteins. Thus these
proteins regulate the supply of acetyl-CoA as well as the synthesis of fatty acids from that substrates. As gestation proceeds
and more lipids are required by the developing placenta fatty acid binding protein content, activity of ATP citrate lyase
and rate of fatty acid synthesis increase indicating a cause and efect relationship between the demand of lipids and supply
of precursor fatty acids during human placental development. 相似文献
117.
The chelating behavior of a new multidentate ligand with tuberculostatic activity toward Cu(II) and Ni(II) ions has been studied. This ligand 3-(2-carboxyhydrazine)phenylimino-2-oximobutane(H2C POB) is found to chelate the above metal ions in both its keto and enol forms. The probable structures of all the complexes and the location of the bonding sites have been established through magnetic and spectroscopic (infrared, electronic) studies. The Cu(II) complex of the enol form exhibits subnormal magnetic moment at room temperature, indicating the probable existence of some sort of super exchange phenomenon in the system. The ligand itself and a few of its Cu(II) complexes have been found to exert powerful in vitro antibacterial activity toward some tuberculosis mycobacteria, such as Mycobacterium flae, Mycobacterium smegmatis, and Mycobacterium H37Rv. 相似文献
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A mutation in the dam gene of Vibrio cholerae: 2-aminopurine sensitivity with intact GATC methylase activity 总被引:1,自引:0,他引:1
R Bandyopadhyay A Sengupta J Das 《Biochemical and biophysical research communications》1989,165(2):561-567
Vibrio cholerae mutants sensitive to 2-aminopurine (2AP) but with DNA adenine methylase activity similar to parental cells have been isolated. The mutant strains were sensitive to ultraviolet light (UV), methyl methane sulphonate (MMS) and 9-aminoacridine. The spontaneous mutation frequency of the mutants were not significantly affected. Attempts to isolate dam V. cholerae cells by screening 2AP sensitive cells have not been successful. All the mutant phenotypes could be suppressed by introducing the plasmid pRB103 carrying the dam gene of Escherichia coli into the mutant cells. 相似文献