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71.
The polymorphism of mtDNA was examined in populations of Old Believers (n = 104) and Russians from Novosibirsk oblast (n = 270). Most of the haplogroups identified belonged to West Eurasian lineages. The frequencies of these haplogroups constituted 96.6% in Russians from Novosibirsk and 93.2% in Old Believers from Tyumen oblast. The populations examined were characterized by a high mtDNA diversity level (h = 0.98) compared to other population samples of Russians from Russia. Among the West Eurasian haplogroups, the most common (a frequency of more than 10%) were haplogroups H, U, J, and T, the proportion of which constituted 77.9% in Old Believers and 83.1% in Russians from Novosibirsk. The Mongoloid admixture in Russians (3.3%) and Old Believers (6.7%) was represented by haplogroups A, D, Z, and C, D, M*, respectively. Statistically significant differences (P < 0.05) were revealed between the Old Believers examined and Bosnians, Czechs, Slovenes, and Russians from the cities of Nizhny Novgorod and Tula. The data obtained confirm the earlier hypothesized influence of the Finno-Ugric component on the East Slavic populations.  相似文献   
72.
The development of an effective malaria vaccine is a high global health priority. Vaccine vectors based on adenovirus type 5 are capable of generating robust and protective T cell and antibody responses in animal models and are currently being evaluated in clinical trials for HIV and malaria. They appear to be more effective in terms of inducing antigen-specific immune responses as compared with non-Ad5 serotype vectors. However, the high prevalence of neutralizing antibodies to Ad5 in the human population, particularly in the developing world, has the potential to limit the effectiveness of Ad5-based vaccines. We have generated novel Ad5-based vectors that precisely replace the hexon hypervariable regions with those derived from Ad43, a subgroup D serotype with low prevalence of neutralizing antibody in humans. We have demonstrated that these hexon-modified adenovectors are not neutralized efficiently by Ad5 neutralizing antibodies in vitro using sera from mice, rabbits and human volunteers. We have also generated hexon-modified adenovectors that express a rodent malaria parasite antigen, PyCSP, and demonstrated that they are as immunogenic as an unmodified vector. Furthermore, in contrast to the unmodified vector, the hexon-modified adenovectors induced robust T cell responses in mice with high levels of Ad5 neutralizing antibody. We also show that the hexon-modified vector can be combined with unmodified Ad5 vector in prime-boost regimens to induce protective responses in mice. Our data establish that these hexon-modified vectors are highly immunogenic even in the presence of pre-existing anti-adenovirus antibodies. These hexon-modified adenovectors may have advantages in sub-Saharan Africa where there is a high prevalence of Ad5 neutralizing antibody in the population.  相似文献   
73.
A study of the reduction of chromium (VI) and nitrate or manganese (IV) ions present in the cultivation medium of denitrifying bacteria of the genus Pseudomonas showed that Cr(VI) ions are reduced first. The rate of Cr(VI) reduction was found to be independent of the presence of Mn(IV) or nitrate ions in the medium.  相似文献   
74.

Background  

Minor alleles of the human dopamine receptor polymorphisms, DRD2/TaqI A and DRD4/48 bp, are related to decreased functioning and/or numbers of their respective receptors and have been shown to be correlated with body mass, height and food craving. In addition, the 7R minor allele of the DRD4 gene is at a higher frequency in nomadic compared to sedentary populations. Here we examine polymorphisms in the DRD2 and DRD4 genes with respect to body mass index (BMI) and height among men in two populations of Ariaal pastoralists, one recently settled (n = 87) and the other still nomadic (n = 65). The Ariaal live in northern Kenya, are chronically undernourished and are divided socially among age-sets.  相似文献   
75.
The influence of cross-linked by dimethylsuberimidate dimeric RNAse from Bacillus intermedius on peritoneal rat macrophages has been investigated in vitro. It has been shown that dimeric RNase with concentrations of 0.5-40.0 mg/ml decreases the functional activities of macrophages. This is manifested in the inhibition of the phagocyte function of macrophages and suppression of the fusion of phagosomes with lysosomes. The change in the cytoplasmatic membrane surface structure induced by the dimers, which is stronger than that induced by monomers, has been demonstrated using atomic force microscopy. The role of membrane properties modification in the inhibition effect of RNase dimers on the functional activities of macrophages is discussed.  相似文献   
76.
Four tick species, Ixodes persulcatus, I. pavlovskyi, I. trianguliceps, and Dermacentor reticulatus, were found in Tomsk and its suburbs in 2006. The species I. pavlovskyi was found to be dominant in the localities situated in Tomsk City, and I. persulcatus was dominant in its suburbs. Viral RNA and viral antigen of the West Nile virus (WNV) were detected in the ticks I. pavlovskyi and I. persulcatus collected in the city and its suburbs by the RT PCR method and enzyme immunoassay with monoclonal antibodies against protein E of the WNV. Average rate of the WNV infected ticks varied from 5.2 up to 11.7% in different localities. Identification of the nucleotide sequence of the protein E gene fragment allowed classifying the cDNA obtained as genotype Ia of the WNV. The sequences are proved similar to the strain LEIV-Vlg99-27889-human of the WNV isolated in Volgograd. The obtained data showed that natural foci of the WNV virus can appear in the city and its suburbs probably involving two dominant tick species. The WNV infected imagoes, larvae, and nymphs of I. persulcatus and I. pavlovskyi were collected from small mammals, lizards, and birds. Therefore we presume that these hosts can be involved in the circulation and distribution of WNV on the territory of Tomsk Region.  相似文献   
77.
Eifelian ammonoids are described for the first time from the Central Kyzylkum Desert (Uzbekistan, Navoiy Region, Aristantau Mountains). The ammonoid assemblage includes the typical Eifelian genera Fidelites, Subanarcestes (a new species S. aristanensis Nikolaeva sp. nov. is described), and Cabrieroceras, found in association with brachiopods, conodonts, and dacryoconarids. The ammonoid assemblage is similar to that from the Chote? beds of Barrandien and their equivalents in the Urals, Salair, Germany, and Morocco (Subanarcestes macrocephalus Zone), suggesting a connection between the Eifelian Kyzylkum Basin, which was part of the Turkestan Paleoocean, and European, North African, Siberian, and Uralian basins. The ammonoids studied are not associated with black shale and apparently existed in normal marine environments.  相似文献   
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Natural dicarbonyls, which may be accumulated during oxidative stress in atherosclerosis (e.g. malondialdehyde) or carbonyl stress in diabetes mellitus (glyoxal and methylglyoxal) effectively inhibited activities of commercial preparations of the antioxidant enzymes: Cu,Zn-superoxide dismutase (Cu,Zn-SOD) and Se-contained glutathione peroxidase from human and bovine erythrocytes, and also rat liver glutathione-S-transferase. After incubation of human erythrocytes with 10 mM of each investigated dicarbonyls the decrease of intracellular Cu,Zn-SOD was observed. The decreased activity of erythrocyte Cu,Zn-SOD was also detected in patients with diabetes mellitus type 2 with carbohydrate metabolism impairments but effective sugar-lowered therapy was accompanied by the increase of this enzyme activity. The increase of erythrocytes Cu,Zn-SOD activity in diabetic patients treated with metformin (which may utilize methylgly-oxal) was higher than in erythrocytes of diabetic patients subjected to traditional therapy.  相似文献   
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