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61.
The purpose of this study was to explore the association of the MCT1 gene Glu490Asp polymorphism (rs1049434) with athletic status and performance of endurance athletes. A total of 1,208 Brazilians (318 endurance athletes and 890 non-athletes) and 867 Europeans (315 endurance athletes and 552 non-athletes) were evaluated in a case–control approach. Brazilian participants were classified based on self-declared ethnicity to test whether the polymorphism was different between Caucasians and Afro-descendants. Moreover, 66 Hungarian athletes underwent an incremental test until exhaustion to assess blood lactate levels, while 46 Russian athletes had their maximum oxygen uptake (VO2max ) compared between genotypes. In the Brazilian cohort, the major T-allele was more frequent in Caucasian top-level competitors compared to their counterparts of lower competitive level (P = 0.039), and in Afro-descendant athletes compared to non-athletes (P = 0.015). Similarly, the T-allele was more frequent in European athletes (P = 0.029). Meta-analysis of the Brazilian and European cohorts confirmed that the T-allele is over-represented in endurance athletes (OR: 1.48, P = 0.03), especially when Afro-descendant athletes were included in the meta-analysis (OR: 1.58, P = 0.005). Furthermore, carriers of the T/T genotype accumulated less blood lactate in response to intense effort (P < 0.01) and exhibited higher VO2max (P = 0.04). In conclusion, the Glu490Asp polymorphism was associated with endurance athletic status and performance. Our findings suggest that, although ethnic differences may exist, the presence of the major T-allele (i.e., the Glu-490 allele) favours endurance performance more than the mutant A-allele (i.e., the 490-Asp allele).  相似文献   
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Supramembrane structures that connect conjugating agrobacterial cells were visualized for the first time by transmission electron microscopy. The primary contact of cells during conjugation was shown to occur through the formation of long pili containing no VirB1 protein. Pretreatment of agrobacterial cells with acetosyringone resulted in a six-to tenfold increase in the transfer frequency of plasmid pTd33 at 19–25°C and had almost no effect at 30°C. The transfer of plasmid pTd33 fromA. tumefaciens strain GV3101 to plasmid-freeA. tumefaciens strain UBAPF-2 was 16 times decreased after the centrifugation of cells. The transfer efficiency of plasmid pTd33 fromA. tumefaciens strain LBA2525 (virB2::lacZ) to plasmid-freeA. tumefaciens strain UBAPF-2 was one order of magnitude lower than the transfer from the wild-typeA. tumefaciens strain GV3101. Treatment of donor cells with 0.01% SDS before mating decreased the transfer efficiency by a factor of 26. The role of pili in the establishment of contact between conjugating cells of agrobacteria is discussed.  相似文献   
63.
We have determined the nucleotide sequence of an 841-bp fragment derived from a segment of the human genome previously cloned by Chumakov et al. [Gene 17 (1982) 19–26] and Zabarovsky et al. [Gene 23 (1983) 379–384] and containing regions homologous to the viral mos gene probe. This sequence displays homology with part of the coding region of the human and murine c-mos genes, contains several termination codons, and is interrupted by two Alu-family elements flanked by short direct repeats. Probably, the progenitor of the human c-mos gene was duplicated approximately at the time of mammalian divergence, was converted to a pseudogene, and acquired insertions of two Alu elements.  相似文献   
64.
Lytic virus infection results in production of a virus progeny and lysis of the infected cell. Tumor cells are usually more sensitive to virus infection. Studies indicate that viral oncolysis provides a promising alternative approach to cancer therapy. The ability of viruses to selectively kill cancer cells is long known, but construction of virus variants with an improved therapeutic potential was impossible until recent advances in virus and cell molecular biology and the development of modern methods for directed modification of viruses. Adenoviruses are one of the best studied models of oncolytic viruses. These DNA viruses are convenient for genetic manipulation and show minimal pathogenicity. The review summarizes the data on the directions and approaches to generation of highly efficient variants of oncolytic adenoviruses. The approaches include introduction of directed genetic modifications into the virus genome, accelerated selection of oncolytic virus variants following treatment with mutagens, the use of adenoviruses as vectors to introduce therapeutic gene products, optimization of viral delivery systems, minimization of the negative effects from the host immune system, etc. The dynamic development of studies in the field holds promise that many variants of oncolytic adenoviruses will find clinical application in the nearest future.  相似文献   
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It is shown that the glycolytic system obtained from the ischemically damaged tissues of rats in the process of the long-term functioning in vitro: partial--after long-term (1.5-2 h) ischemia and completely--after short-term (15-30 min) ischemia. Detection of reversible changes in the glycolytic system under ischemia, besides determination of its activity with the short-term functioning is promoted by isolation of the glycolytic system from tissues as well as prevention of the damage in vitro.  相似文献   
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The results of a long-term (1999–2007) investigation of vegetation productivity and carbon dioxide (CO2) emission from the surface of an oligotrophic mire in southern taiga in Western Siberia are presented. The studied ecosystems include pine—shrub—sphagnum (PSS) community, a similar community with oppressed (low) tree stand (LPSS), and sedge—sphagnum fen (SSF). Net primary production for PSS, LPSS and SSF are equal to 552, 575, and 561 g m?2 yr?1. The mean respiration during the snow-free season determined by chamber method is 165.8, 105.6, 112.4 mgCO2 m?2 h?1 for PSS, LPSS and SSF, respectively. Field measurements of NPP and CO2 emission in combination with reference data on methane emission, winter CO2 and CH4 emissions and carbon export by river run–off were used to develop an overall carbon budget of the mire ecosystems. At present conditions the studied mire ecosystems are net sinks for atmospheric carbon and accumulate peat. Rates of the actual modern carbon accumulation are equal to 21, 112 and 102 g C m?2 yr?1 for PSS, LPSS and SSF communities.  相似文献   
70.
Preclinical studies demonstrate that a broad spectrum of human and animal malignant cells can be killed by oncolytic paramyxoviruses, which includes cells of ecto-, endo- and mesodermal origin. In clinical trials, significant reduction or even complete elimination of primary tumors and established metastases has been reported. Different routes of virus administration (intratumoral, intravenous, intradermal, intraperitoneal, or intrapleural) and single- vs. multiple-dose administration schemes have been explored. The reported side effects were grades 1 and 2, with the most common among them being mild fever. There are certain advantages in using paramyxoviruses as oncolytic agents compared to members of other virus families exist. Thanks to cytoplasmic replication, paramyxoviruses do not integrate the host genome or engage in recombination, which makes them safer and more attractive candidates for widely used therapeutic oncolysis than retroviruses or some DNA viruses. The list of oncolytic Paramyxoviridae members includes the attenuated measles virus, mumps virus, low pathogenic Newcastle disease, and Sendai viruses. Metastatic cancer cells frequently overexpress certain surface molecules that can serve as receptors for oncolytic paramyxoviruses. This promotes specific viral attachment to these malignant cells. Paramyxoviruses are capable of inducing efficient syncytium-mediated lysis of cancer cells and elicit strong immune stimulation, which dramatically enforces anticancer immune surveillance. In general, preclinical studies and phases I–III of clinical trials yield very encouraging results and warrant continued research of oncolytic paramyxoviruses as a particularly valuable addition to the existing panel of cancer-fighting approaches.  相似文献   
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