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1.
Severe bioprosthetic mitral valve calcification is a significant problem in cardiovascular surgery. Unfortunately, clinical markers did not demonstrate efficacy in prediction of severe bioprosthetic mitral valve calcification. Here, we examined whether a genomics-based approach is efficient in predicting the risk of severe bioprosthetic mitral valve calcification. A total of 124 consecutive Russian patients who underwent mitral valve replacement surgery were recruited. We investigated the associations of the inherited variation in innate immunity, lipid metabolism and calcium metabolism genes with severe bioprosthetic mitral valve calcification. Genotyping was conducted utilizing the TaqMan assay. Eight gene polymorphisms were significantly associated with severe bioprosthetic mitral valve calcification and were therefore included into stepwise logistic regression which identified male gender, the T/T genotype of the rs3775073 polymorphism within the TLR6 gene, the C/T genotype of the rs2229238 polymorphism within the IL6R gene, and the A/A genotype of the rs10455872 polymorphism within the LPA gene as independent predictors of severe bioprosthetic mitral valve calcification. The developed genomics-based model had fair predictive value with area under the receiver operating characteristic (ROC) curve of 0.73. In conclusion, our genomics-based approach is efficient for the prediction of severe bioprosthetic mitral valve calcification.  相似文献   
2.
The ability of treatment of pulp and paper production wastewater is showed by carbon-graphite and polymeric membranes. The influence of lignins, organic and inorganic substances containing in wastewater on specific capacity is studied. Capacity calculation of different types of membrane is suggested.  相似文献   
3.
We investigated the effect of beta-amyloid peptide (betaA) on the activation of the murine-derived monocyte/macrophage J774 cell-line. BetaA induced tumor necrotic factor-alpha (TNF alpha) in these cells in a dose-dependent manner. Incubation of cells with betaA slightly increased nitric oxide (NO) production, an effect that was significantly enhanced by the addition of interferon-gamma (IFN gamma). Substitution of betaA4 with TFN alpha and incubation of the cultures with IFN gamma resulted in significant NO production, although this was lower than that obtained in the presence of the peptide. Incubation of cultures with a monoclonal antibody (mAb) against TNF alpha abrogated NO production. Our results suggest that betaA4-induced TNF alpha production is a crucial event in the activation of peripheral macrophages.  相似文献   
4.
Bacillus thuringiensis, commonly referred to as Bt, is an object of the lasting interest of microbiologists due to its highly effective insecticidal properties, which make Bt a prominent source of biologicals. To categorize the exuberance of Bt strains discovered, serotyping assays are utilized in which flagellin serves as a primary seroreactive molecule. Despite its convenience, this approach is not indicative of Bt strains’ phenotypes, neither it reflects actual phylogenetic relationships within the species. In this respect, comparative genomic and proteomic techniques appear more informative, but their use in Bt strain classification remains limited. In the present work, we used a bottom-up proteomic approach based on fluorescent two-dimensional difference gel electrophoresis (2D-DIGE) coupled with liquid chromatography/tandem mass spectrometry(LC-MS/MS) protein identification to assess which stage of Bt culture, vegetative or spore, would be more informative for strain characterization. To this end, the proteomic differences for the israelensis-attributed strains were assessed to compare sporulating cultures of the virulent derivative to the avirulent one as well as to the vegetative stage virulent bacteria. Using the same approach, virulent spores of the israelensis strain were also compared to the spores of strains belonging to two other major Bt serovars, namely darmstadiensis and thuringiensis. The identified proteins were analyzed regarding the presence of the respective genes in the 104 Bt genome assemblies available at open access with serovar attributions specified. Of 21 proteins identified, 15 were found to be encoded in all the present assemblies at 67% identity threshold, including several virulence factors. Notable, individual phylogenies of these core genes conferred neither the serotyping nor the flagellin-based phylogeny but corroborated the reconstruction based on phylogenomics approaches in terms of tree topology similarity. In its turn, the distribution of accessory protein genes was not confined to the existing serovars. The obtained results indicate that neither gene presence nor the core gene sequence may serve as distinctive bases for the serovar attribution, undermining the notion that the serotyping system reflects strains’ phenotypic or genetic similarity. We also provide a set of loci, which fit in with the phylogenomics data plausibly and thus may serve for draft phylogeny estimation of the novel strains.  相似文献   
5.
6.
IL-4 is a Th2-derived cytokine which plays an important role in the function of various immunocompetent cells as well as in the pathophysiology of various CNS disorders. In this study we characterized the expression of IL-4R in cultured astrocytes and explored the effects of IL-4 on the function of these cells. We found that astrocytes express the mRNA of both the membrane-bound and the soluble forms of the IL-4R, whereas they do not secrete IL-4. IL-4 inhibited both NO production and iNOS expression induced by LPS stimulation and decreased the secretion of TNF-alpha and the expression of ICAM-1. In contrast, IL-4 induced the secretion of NGF by astrocytes and synergized with LPS and TNF-alpha in this effect. These results suggest an important role for IL-4 as an immunosuppressive and a neurotrophic factor in the CNS.  相似文献   
7.
The issue of discovering an optimal debt portfolio in case of oil company under oil price uncertainty is considered in the paper. New algorithm to build optimal debt structure is proposed. It is shown that optimal portfolio reduces financial risk in case of oil price uncertainty. Non-parametric approximation is used to describe functional relationship between US dollar and Russian ruble, considered as commodity currency.  相似文献   
8.
The present study shows that ball-milled nanosized powders of TaC and NbC can be successfully sintered to high densities at 1300?1400 °C for 30 min under vacuum. Fabricated ceramics demonstrate hardness of 20?25 GPa due to decrease in carbon stoichiometry and submicron grain size. The main techniques to investigate the underlying phenomena during processing of initial powders were XRD, SEM and TGA-DSC. After milling, carbide particles demonstrate a significant amount of oxygen impurities but no signs of oxidation. During sintering, these impurities react with structural carbon and metal ions, which results in decarburization and segregation of oxides. Above 1000 °C, the oxide phases undergo partial reduction by structural carbon, promoting decarburization even further. Densification starts shortly after the reduction of oxides and provides dense microstructures. The effects of decarburization and oxide segregation can be compensated by carbon excess, however it can be difficult to control densification curve in such case.  相似文献   
9.
Improving the mechanical performance of nanocrystalline functional oxides can have major implications for stability and resilience of battery cathodes, development of reliable nuclear oxide fuels, strong and durable catalytic supports. By combining Monte Carlo simulations, experimental thermodynamics, and in-situ transmission electron microscopy, we demonstrate a novel toughening mechanism based on interplay between the thermo-chemistry of the grain boundaries and crack propagation. By using zirconia as a model material, lanthanum segregation to the grain boundaries was used to increase the toughness of individual boundaries and simultaneously promote a smoother energy landscape in which cracks experience multiple deflections through the grain boundary network, ultimately improving fracture toughness.  相似文献   
10.
Microbial electrolysis cells (MECs) could be integrated with dark fermentative hydrogen production to increase the overall system yield of hydrogen. The influence of catholyte pH on hydrogen production from MECs and associated parameters such as electrode potentials (vs Ag/AgCl), COD reduction, current density and quantity of acid needed to control pH in the cathode of an MEC were investigated. Acetate (10 mM, HRT 9 h, 24 °C, pH 7) was used as the substrate in a two chamber MEC operated at 600 mV and 850 mV applied voltage. The effect of catholyte pH on current density was more significant at an applied voltage of 600 mV than at 850 mV. The highest hydrogen production rate was obtained at 850 mV, pH 5 amounting to 200 cm3stp/lanode/day (coulombic efficiency 60%, cathodic hydrogen recovery 45%, H2 yield 1.1 mol/mol acetate converted and a COD reduction of 30.5%). Within the range (18.5–49.4 °C) of temperatures tested, 30 °C was found to be optimal for hydrogen production in the system tested, with the performance of the reactor being reduced at higher temperatures. These results show that an optimum temperature (approximately 30 °C) exists for MEC and that lower pH in the cathode chamber improves hydrogen production and may be needed if potentials applied to MECs are to be minimised.  相似文献   
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