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101.
102.
Incubation in vitro of rat liver nuclei in the presence of S-adenosyl[methyl-(3)H]methionine ([(3)H] SAM) leads to incorporation of the radioactive label not only into core-histones H3 and H4, but also into linker histone H1. Addition of distamycine A to the incubation medium stimulates label incorporation into histone H1 ~ in 6 times and into histone H3 ~ in 2 times. The presence of distamycine facilitates histone H1 extraction by polyglutamic acid (poly(Glu)) and decreases of UV-induced DNA-histone cross-links formation. These effects give evidence of weakening of H1-chromatin interaction by distamycin to be results of histone H1 position change relative to nucleosome and(or) disturbance of histones H1-H3 interactions so as these histones are exposed to additional methylation. 相似文献
103.
M. V. Zubasheva L. A. Ganushkina T. A. Smirnova R. R. Azizbekyan 《Applied Biochemistry and Microbiology》2010,46(8):755-762
The optimum conditions for growth, sporulation, and crystal-formation in four isolated crystal-forming strains of Bacillus laterosporus were determined. It was shown that culture broth and pellets of bacterial culture liquid possess larvicidal activity against
larvae of mosquitoes A. stephensi and A. aegypti. The protein nature of crystal was shown. Crystals are monocomponent containing a protein with MM of 68 or 130 kDa. Purified
protein crystals demonstrated larvicidal activity. Specific larvicidal activity of crystals of various strains essentially
differed. High larvicidal activity of B. laterosporus strains allows for them to be recommended as producers of antimosquito biological preparations. 相似文献
104.
S. B. Smirnova 《Paleontological Journal》2010,44(1):95-98
Four species of a new genus, Chomsiipites—Ch. libanicus sp. nov., Ch. pyriformis sp. nov., Ch. dzyubae sp. nov., and Ch. zaklinskaiae (Azèma et Boltenhagen) comb. nov.—are described from the Albian-Cenomanian of western part of Central Lebanon, Eastern Caspian
Region, Albian-Turonian of Gabon, and Albian-Senonian of Angola (Equatorial Africa). 相似文献
105.
106.
The effect of various doses of L-lysine-alpha-oxidase gel (1.4-3.5 and 70 mcg/ml) on development of eye and skin herpetic lesions due to type 1 herpes simplex virus was studied on rabbits. The doses of 1.4 to 3.5 mcg/ml were not sufficient for the therapeutic effect. The dose of 70 mcg/ml provided complete healing of the lesions in 3 to 4 days. The results were confirmed by the immunological tests. 相似文献
107.
108.
Smirnova AS Ferreira-Silva KC Mine KL Andrade-Oliveira V Shulzhenko N Gerbase-DeLima M Morgun A 《Immunogenetics》2007,59(1):93-98
Various single nucleotide polymorphisms (SNPs) have been investigated regarding association with gene expression levels or
human diseases. Although different SNPs within one gene are frequently analyzed individually, it is highly probable that in
the majority of the cases, a precise combination of SNP alleles, i.e., haplotype, determines a functional trait. Methods commonly
used for haplotype determination, involving studies in families, cloning, or somatic cell hybrids, are expensive and time-consuming.
We herein suggest a novel and simple strategy for haplotype determination, involving selective haplotype depletion with a
restriction enzyme, followed by sequencing. We studied 11 LTA gene polymorphisms in 102 Brazilian individuals, and we applied this novel methodology for haplotyping 67 out of 70 LTA heterozygous individuals. We concluded that the method is rapid and efficient, and, as it includes only simple and widespread-used
techniques, it could be used in most of the laboratories without further investment in equipments. The wider usage of haplotyping
could be important to clarify contradictory results frequently observed among studies that focus on a single SNP.
Maria Gerbase-DeLima and Andrey Morgun are co-senior authors. 相似文献
109.
Ikryannikova LN Afanas'ev MV Akopian TA Il'ina EN Kuz'min AV Larionova EE Smirnova TG Chernousova LN Govorun VM 《Journal of microbiological methods》2007,70(3):395-405
A MALDI TOF MS based minisequencing method has been developed and applied for the analysis of rifampin (RIF)- and isoniazid (INH)-resistant M. tuberculosis strains. Eight genetic markers of RIF resistance-nucleotide polymorphisms located in RRDR of rpoB gene, and three of INH resistance including codon 315 of katG gene and − 8 and − 15 positions of the promoter region of fabG1-inhA operon were worked out. Based on the analysis of 100 M. tuberculosis strains collected from the Moscow region in 1997–2005 we deduced that 91% of RIF-resistant and 94% of INH-resistant strains can be identified using the technique suggested. The approach is rapid, reliable and allows to reveal the drug resistance of M. tuberculosis strains within 12 h after sample isolation. 相似文献
110.
The effect of mutations in the genes encoding glutathione, glutaredoxin, thioredoxin, and thioredoxin reductase on the response of growing Escherichia coli to oxidative stress was studied. The gshA mutants defective in glutathione synthesis had the lowest resistance to high doses of H2O2, whereas the trxB mutants defective in thioredoxin reductase synthesis had the highest resistance to this oxidant, exceeding that of the parent strain. Among the studied mutants, the trxB cells demonstrated the highest basic levels of catalase activity and intracellular glutathione; they were able to rapidly reach the normal GSH level after oxidative stress. At the same time, these bacteria showed high frequency of induced mutations. The expression of the katG and sulA genes suggests that, having different sensitivity to high oxidant concentrations, the studied mutants differ primarily in their ability to induce the antioxidant genes of the OxyR and SOS regulons. 相似文献