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51.
Davis FJ Gupta M Camoretti-Mercado B Schwartz RJ Gupta MP 《The Journal of biological chemistry》2003,278(22):20047-20058
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Removal of some commonly used protecting groups in peptide synthesis by catalytic transfer hydrogenation employing hydrazinium monoformate and 10%Pd on carbon is described. This method is equally competitive with other methods in deblocking most of the commonly used protecting groups in peptide synthesis. tert-Butyl derived and base labile protecting groups were completely stable under these conditions. This is more effective than hydrazine or formic acid. 相似文献
54.
Replication and compartmentalization of HIV-1 in kidney epithelium of patients with HIV-associated nephropathy 总被引:11,自引:0,他引:11
Marras D Bruggeman LA Gao F Tanji N Mansukhani MM Cara A Ross MD Gusella GL Benson G D'Agati VD Hahn BH Klotman ME Klotman PE 《Nature medicine》2002,8(5):522-526
HIV-associated nephropathy is a clinicopathologic entity that includes proteinuria, focal segmental glomerulosclerosis often of the collapsing variant, and microcystic tubulointerstitial disease. Increasing evidence supports a role for HIV-1 infection of renal epithelium in the pathogenesis of HIV-associated nephropathy. Using in situ hybridization, we previously demonstrated HIV-1 gag and nef mRNA in renal epithelial cells of patients with HIV-associated nephropathy. Here, to investigate whether renal epithelial cells were productively infected by HIV-1, we examined renal tissue for the presence of HIV-1 DNA and mRNA by in situ hybridization and PCR, and we molecularly characterized the HIV-1 quasispecies in the renal compartment. Infected renal epithelial cells were removed by laser-capture microdissection from biopsies of two patients, DNA was extracted, and HIV-1 V3-loop or gp120-envelope sequences were amplified from individually dissected cells by nested PCR. Phylogenetic analysis of kidney-derived sequences as well as corresponding sequences from peripheral blood mononuclear cells of the same patients revealed evidence of tissue-specific viral evolution. In phylogenetic trees constructed from V3 and gp120 sequences, kidney-derived sequences formed tissue-specific subclusters within the radiation of blood mononuclear cell-derived viral sequences from both patients. These data, along with the detection of HIV-1-specific proviral DNA and mRNA in tubular epithelium cells, argue strongly for localized replication of HIV-1 in the kidney and the existence of a renal viral reservoir. 相似文献
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Subramanian M Chintalwar GJ Chattopadhyay S 《Indian journal of biochemistry & biophysics》2003,40(1):22-26
Radioprotective activity of a polysaccharide preparation from the Indian medicinal plant. Tinospora cordifolia Miers has been established using Saccharomyces cerevisiae X2180 strain as the in vivo test model. The entire activity could be attributed to the radical scavenging capacity of the preparation, as it did not enhance the expression of the protective enzymes, catalase and superoxide dismutase in the yeast cells. 相似文献
57.
Drosophila nasuta albomicans (with 2n = 6), contains a pair of metacentric neo-sex chromosomes. Phylogenetically these are products of centric fusion
between ancestral sex (X, Y) chromosomes and an autosome (chromosome 3). The polytene chromosome complement of males with
a neo-X- and neo-Y-chromosomes has revealed asynchrony in replication between the two arms of the neo-sex chromosomes. The
arm which represents the ancestral X-chromosome is faster replicating than the arm which represents ancestral autosome. The
latter arm of the neo-sex chromosome is synchronous with other autosomes of the complement. We conclude that one arm of the
neo-X/Y is still mimicking the features of an autosome while the other arm has the features of a classical X/Y-chromosome.
This X-autosome translocation differs from the other evolutionary X-autosome translocations known in certain species ofDrosophila. 相似文献
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Philine G. D. Feulner Frédéric J. J. Chain Mahesh Panchal Yun Huang Christophe Eizaguirre Martin Kalbe Tobias L. Lenz Irene E. Samonte Monika Stoll Erich Bornberg-Bauer Thorsten B. H. Reusch Manfred Milinski 《PLoS genetics》2015,11(2)
The patterns of genomic divergence during ecological speciation are shaped by a combination of evolutionary forces. Processes such as genetic drift, local reduction of gene flow around genes causing reproductive isolation, hitchhiking around selected variants, variation in recombination and mutation rates are all factors that can contribute to the heterogeneity of genomic divergence. On the basis of 60 fully sequenced three-spined stickleback genomes, we explore these different mechanisms explaining the heterogeneity of genomic divergence across five parapatric lake and river population pairs varying in their degree of genetic differentiation. We find that divergent regions of the genome are mostly specific for each population pair, while their size and abundance are not correlated with the extent of genome-wide population differentiation. In each pair-wise comparison, an analysis of allele frequency spectra reveals that 25–55% of the divergent regions are consistent with a local restriction of gene flow. Another large proportion of divergent regions (38–75%) appears to be mainly shaped by hitchhiking effects around positively selected variants. We provide empirical evidence that alternative mechanisms determining the evolution of genomic patterns of divergence are not mutually exclusive, but rather act in concert to shape the genome during population differentiation, a first necessary step towards ecological speciation. 相似文献