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61.
Carriage frequencies of alleles and genotypes of polymorphous locus of -174G>C IL6 (rs1800795) were analyzed in the patients with ischemic stroke (IS) of Russian ethnic descent (200 cases) and in the control group of the same ethnic descent with similar sex and age (140 controls). Significant differences were identified in frequencies of carriage (in homo- or heterozygous form) of allele IL6*-174G (p = 0.0029, OR = 2.9, 95% CI: 1.4-5.8), which can be considered as risk factor for IS and in frequencies of IL6*-174C/C genotype carriage, correspondingly (p = 0.0029, OR = 0.35, 95% CI: 0.17-0.69). After sex stratification of patients and controls similar significant differences were observed only between female patients and controls, after age stratification the difference was observed only for the age group older 60 years. Complex analysis of association of SNP -174G>C IL6 alleles and genotypes carriage in combination with SNP 4266A>G (Thr312Ala) FGA (rs6050) (see symbol) -249C>T FGB (rs1800788) with IS revealed protective combinations IL6*-174C/C + FGA* 4266A (see symbol) IL6*-174C/C + FGB*-249C, which were slightly more significant than single protective genotype IL6*-174C/C associated with IS and their ORs didn't differ substantially from the single genotypes's OR value. At the same time the combinations of alternative allele IL6*-174G with the same FGB*-249C or FGA* 4266A alleles were revealed and their association significance levels as well as OR values were lower than the values for the single risk allele IL6*-174G. In case of the mutual carriage of IL6*-174G allele with FGA*4266A/A, FGB*-249C/C genotypes or with combinations of these alleles/genotypes the "neutralized" effect became stronger. In other words, we observed association of IS with allele/genotype combinations of genes IL6, FGA and FGB, in which IL6 plays key role and FGA and FGB have modulating function. In analysis of association of fibrinogen plasma levels with three analyzed polymorphous loci significant differences were not revealed.  相似文献   
62.
In four ground squirrel species from the Volga region-yellow (Spermophilus fulvus), russet (S. major), little (S. pygmaeus), and speckled (S. suslicus)--four hybridization variants (major/fulvus, major/pygmaeus, major/suslicus, and pygmaeus/suslicus) have been reliably described. Earlier we have shown that populations of S. major from the Volga region were characterized by wide introgression of mtDNA from S. fulvus and S. pygmaeus, which probably, resulted from ancient hybridization. In this study, the same populations were used to analyze the introgression of the Y chromosome, which (unlike mtDNA) is paternally inherited. Three genes, ZfY, SRY, and SmcY were tested as Y-chromosomal candidate markers. It was demonstrated that Y chromosome of ground squirrels lacked the ZfY gene, while its homologous structure, ZfY(X), was presumably linked to the X chromosome. The SRY region examined was rather conservative. In particular, the sequences determined in S. major and S. fulvus were identical, while three out of four substitutions found in S. pygmaeus were located in the coding region. The SmcY gene was found to be the most suitable marker, providing distinguishing of all of the four ground squirrel species by nine nucleotide substitutions. Introgression at the Y chromosome was observed only in two cases: in one S. major individual (out of 51 phenotypically pure animals) caught in the major/fulvus sympatry zone, and in four (one litter) out of fourteen S. fulvus individuals caught in close vicinity of the sympatry zone of these two species. Among 28 S. pymaeus and 9 S. suslicus individuals, no foreign SmcY genes were detected. Two colonies of the "hybrid accumulation" type were examined with eight major/suslicus hybrids analyzed in the first and seventeen major/fulvus hybrids in the second colony. The prevalence of the S. major paternal lineages was observed in both colonies (87.5 and 82.4%, respectively). The data obtained suggest that compared to wide mtDNA introgression, introgression of Y chromosome in the Volga region ground squirrels is statistically significantly less frequent event.  相似文献   
63.
The rare olean-18(19)-ene triterpenoids moradiol and moronic acid were synthesized from betulin, and their antiviral properties were investigated.  相似文献   
64.
65.
The Medicago truncatula ornithine aminotransferase cDNA was cloned under the potent constitutive 35S RNA promoter of the cauliflower mosaic virus and transferred into the genome of tobacco Nicotiana tabacum SR1 plants. Transformed tobacco plants grew better in salinity stress, but did not differ in proline content under normal or stress conditions from control plants. It was assumed that the role of ornithine aminotransferase in the molecular mechanisms of stress resistance is not associated with additional proline synthesis.  相似文献   
66.
The genetic impact of the 1986 accident at the Ukraine Chernobyl Nuclear Power Plant (NPP) on populations of living organisms has yet to be fully assessed. Monitoring of the genotoxicity of polluted soils is a key element in the disaster management program. We used Arabidopsis thaliana and Nicotiana tabacum plants transgenic for a reporter gene revealing homologous recombination to study the genetic effects of chronic low-dose radiation stemming from the soil in inhabited areas of Ukraine where contamination by the accident ranges from 1 to 40 Ci/km2. We noted a significant dose-dependent increase of homologous recombination in plants cultivated in the affected inhabited areas, proving the persistently high genotoxicity of the radioactively contaminated soils.  相似文献   
67.
The subunits of the F0 membrane sector of bovine heart mitochondrial H(+)-ATPase that contact the lipids of the mitochondrial inner membrane were identified with the use of specially synthesized proteoliposomes that contained active mitochondrial H(+)-ATPase and a photoreactive lipid, which was 1-acyl-2-[12-(diazocyclopentadiene-2-carbonylamino)-[12-14C]dodecanoyl]-sn- glycero-3-phosphocholine, 1-acyl-2-[11-([125I]diazoiodocyclopentadiene-2-carbonyloxy)undecanoyl]-sn- glycero-3-phosphocholine, or 1-acyl-2-[12-(diazocyclopentadiene-2-carbonylamino)dodecanoyl]-sn-glycero- 3-phosphocholine, where acyl is a mixture of the residues of palmitic (70%) and stearic (30%) acids. An analysis of the cross-linked products obtained upon the UV-irradiation of these proteoliposomes indicated that subunits c and a of the F0 membrane sector contact the lipids. The cross-linked products were identified by SDS-PAGE and MALDI mass spectrometry.  相似文献   
68.
Thermoregulatory responses to exercise in relation to the phase of the menstrual cycle were studied in ten women taking oral contraceptives (P) and in ten women not taking oral contraceptives (NP). Each subject was tested for maximal aerobic capacity ( ) and for 50% exercise in the follicular (F) and luteal (L) phases of the menstrual cycle. Since the oral contraceptives would have prevented ovulation a quasi-follicular phase (q-F) and a quasi-luteal phase (q-L) of the menstrual cycle were assumed for P subjects. Exercise was performed on a cycle ergometer at an ambient temperature of 24° C and relative air humidity of 50%. Rectal (T re), mean skin ( ), mean body ( ) temperatures and heart rate (f c) were measured. Sweat rate was estimated by the continuous measurement of relative humidity of air in a ventilated capsule placed on the chest, converted to absolute pressure (PH2Ochest). Gain for sweating was calculated as a ratio of increase inPH2Ochest to the appropriate increase inT re for the whole period of sweating (G) and for unsteady-state (Gu) separately. The did not differ either between the groups of subjects or between the phases of the menstrual cycle. In P, rectal temperature threshold for sweating (T re, td) was 37.85° C in q-L and 37.60° C in q-F (P < 0.01) and corresponded to a significant difference fromT re at rest. TheT re, andf c increased similarly during exercise in q-F and q-L. No menstrual phase-related differences were observed either in the dynamics of sweating or in G. In NP,T re, td was shorter in L than in F (37.70 vs 37.47° C,P<0.02) with a significantly greater value fromT re at rest. The dynamics and G for sweating were also greater in L than in F. The Gu was 36.8 versus 16.6 kPa · ° C–1 (P<0.01) while G was 6.4 versus 3.8 kPa · ° C–1 (P<0.05), respectively. TheT re, andf c increased significantly more in phase F than in phase L. It was concluded that in these women performing moderate exercise, there was a greater temperature threshold and larger gains for sweating in phase L than in phase F. Intake of oral contraceptives reduced the differences in the gains for sweating making the thermoregulatory responses to exercise more uniform.  相似文献   
69.
It is shown that estradiol in the presence of horse radish peroxidase interacts with hydrogen peroxide, which is evidenced by an increase in its optical density at 280 nm. The photometering of samples containing estradiol and horse radish peroxidase upon their titration with hydrogen peroxide indicated that the increase in optical density stops after introducing hydrogen peroxide equimolar in concentration to estradiol. The stoichiometric ratio of estradiol consumed during oxidative destruction to hydrogen peroxide was 1:1. In the presence of ascorbate, the oxidative destruction of estradiol by the action of hydrogen peroxide, catalyzed by horse radish peroxidase, was observed only after a latent period and showed the same regularities as in the absence of ascorbate. It was found by calorimetry that, during the latent period, estradiol catalyzes the degradation of hydrogen peroxide and ascorbate without undergoing oxidative destruction. The substrates of the peroxidase reaction benzidine, 1-naphthol, and phenol interact with hydrogen peroxide in the presence of ascorbate and horse radish peroxidase in a similar way. Presumably, upon interaction with hydrogen peroxide in the presence of horse radish peroxidase, estradiol, like other substrates of this reaction, undergoes oxidative destruction by the mechanism of peroxidase reaction. It is shown that oxidative destruction of estradiol by the action of hydrogen peroxide can also be catalyzed by methemoglobin by the same mechanism. These data are important for understanding the role of estradiol in the organism and the pathways of its metabolic conversions.  相似文献   
70.
One of the main problems of metabolic engineering is to determine the genetically controlled limiting links of a metabolic network. We have built a model of the primary transport of inorganic phosphates (Pi), analyzed the Pi metabolic network in Gram-negative bacteria, and determined the factors controlling the phosphate exchange. The model explains why the Pi primary transport is not observed at the release stage. The nonlinearity of primary transport and the differences in its parameters in the membrane and within the cell give rise to transport asymmetry, i.e., the Pi release rate is low as compared with the uptake rate, and is small at the background of secondary transport. Discussed is a general scheme of coordination between primary and secondary transport, which are interconnected through the substrate-product reration.  相似文献   
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