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881.
882.
Rift Valley fever (RVF) is a severe viral zoonosis in Africa and the Middle East that harms both human health and livestock production. It is believed that RVF in Egypt has been repeatedly introduced by the importation of infected animals from Sudan. In this paper, we propose a three-patch model for the process by which animals enter Egypt from Sudan, are moved up the Nile, and then consumed at population centers. The basic reproduction number for each patch is introduced and then the threshold dynamics of the model are established. We simulate an interesting scenario showing a possible explanation of the observed phenomenon of the geographic spread of RVF in Egypt.  相似文献   
883.
Highlights? IKK can inhibit TNFα-induced apoptosis independently of NF-κB activation ? Inhibition of BAD constitutes the NF-κB-independent antiapoptotic axis of IKK ? IKK phosphorylates BAD at Ser26 and primes it for inactivation ? BAD inactivation coordinates with NF-κB activation to suppress TNFα-induced apoptosis  相似文献   
884.
885.
Intestinal inflammation causes metabolic disorders. The purpose of this study was to determine the effect of dietary supplementation with lactosucrose (LS) on the serum metabolome and intestinal luminal content of fatty acids in colitic rats. Colitis was induced in rats using trinitrobenzene sulfonic acid. Subsequently, rats received intragastric administration of either 250 mg LS/kg body weight or saline (the control group) every day for 5 weeks. Short-chain fatty acids in the intestinal lumen, blood profile, and metabolites in serum were measured, respectively, using gas chromatography, biochemistry analyzer, and nuclear magnetic resonance-based metabolomics combined with multivariate statistics. Metabolic effects of LS included: (1) decreases in concentrations of branched-chain amino acids (isoleucine and valine), alanine, citric acid, trimethylamine oxide and taurine, and the abundance of aspartate aminotransferase in serum; (2) increases in concentrations of glucose metabolites (including succinate) in serum; and (3) altered concentrations of butyrate in the cecal content and of butyrate and acetate in the colon content. The results indicate that LS supplementation to colitic rats affects whole-body metabolism of amino acids and release of aspartate aminotransferase and alkaline phosphatase from tissues into the blood circulation, and enhances the production of short-chain fatty acids in the intestinal lumen.  相似文献   
886.
887.
A moderately halophilic bacteria designed strain NY-011T was isolated from the high salt culture of Dunaliella salina in Chengdu of Sichuan Province, China. The isolate was Gram-negative, nonmotile, rod-shaped and 12.5–21.6 μm in length. Colonies on solid media are circular, wet, smooth and cream. The strain grew optimally at 37 °C, pH 7.0 and in the presence of 8 % NaCl. Acid was produced from glycerol, d-arabinose, glucose, trehalose, inositol, mannose, mannitol, sucrose, maltose and sorbitol. Catalase is produced but not oxidase. The major fatty acids are C18: 1ω7c (37.59 %), C19: 0 cyclo ω8c (18.29 %), C16: 0 (16.05 %) and C6: 0 (12.43 %). The predominant respiratory lipoquinone found in strain NY-011T is ubiquinone with nine isoprene units (Q-9). The genomic DNA G + C content of strain NY-011T was 62.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain NY-011T belonged to the genus Halomonas. The highest levels of 16S rRNA gene sequence similarity were found between the strain NY-011T and H. pantelleriensis (sequence similarity 98.43 %). However, the levels of DNA–DNA relatedness between them were only 23.1 %. In addition, the strain NY-011T had a phenotypic profile that readily distinguished it from H. pantelleriensis. The strain NY-011T therefore represents a new species of the genus Halomonas, for which the name Halomonas socia sp. nov. is proposed, with NY-011T (=CCTCC AB 2011033T = KCTC 23671T) as the type strain.  相似文献   
888.
The authors demonstrate herein a novel time-resolved fluoroimmunoassay (TRFIA) protocol for quantification of human IgG with the new bifunctional chelate Eu(TTA)3(5-NH2-phen) (ETNP) labeling the goat anti-human IgG. The immunoassay was conducted by following the typical procedure for sandwich-type immunoreactions. Goat anti-human IgG was immobilized on aldehyde-modified glass slides. The human IgG analyte was first captured by the primary antibody and then sandwiched by a secondary antibody labeled with the chelate ETNP. The experimental procedure was simple to follow and gave desirable levels of sensitivity and low limits of detection. To the best of our knowledge, this is the first application of the new chelate, ETNP, in an immunoassay. In comparison to typical organic, fluorescent compounds and other lanthanide fluorescent chelates used in immunoassay, the detection sensitivity of our method using ETNP chelate in the solid phase was greatly improved and a concentration of human IgG about 5 μg/L could be detected under optimal conditions. The main result of this work shows that the new chelate ETNP can be applied as a powerful fluorescent labeling material for constructing ultrasensitive TRFIAs. The detection of human IgG, using ETNP as the chelate, is a model example of the effectiveness of this immunoassay. Many other types of antigen–antibody immunoassays should be possible using the protocol described herein.  相似文献   
889.
A novel Gram-negative, catalase- and oxidase-positive, strictly aerobic, non spore-forming, rod-shaped bacterium, designated strain JSM 083058T, was isolated from non-saline forest soil in Hunan Province, China. Growth occurred with 0–8% (w/v) NaCl (optimum, 0.5–3%) at pH 6.0–10.0 (optimum, pH 7.0) and at 5–35°C (optimum, 25–30°C). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain JSM 083058T fell within the cluster comprising species of the genus Sphingomonas, clustering with Sphingomonas aestuarii K4T, with which it shared highest 16S rRNA gene sequence similarity (99.2%). The chemotaxonomic properties of strain JSM 083058T were consistent with those of the genus Sphingomonas. The predominant respiratory quinone was ubiquinone Q-10, and the major cellular fatty acids were summed feature 8 (C18:1ω7c/C18:1ω6c), C16:0, summed feature 3 (C16:1ω7c/C16:1ω6c) and C17:1ω6c. The polar lipids consisted of diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid. The genomic DNA G+C content of strain JSM 083058T was 65.5 mol%. The combination of phylogenetic analysis, DNA–DNA relatedness, phenotypic characteristics and chemotaxonomic data supported the view that strain JSM 083058T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas hunanensis sp. nov. is proposed. The type strain is JSM 083058T (=CCTCC AA 209011T = DSM 22213T).  相似文献   
890.
Anaerophaga sp. strain HS1 was isolated from offshore hot spring sediment in Xiamen, China. It was identified as a novel, moderately thermophilic, strictly anaerobic bacterium affiliated with the family Marinilabiaceae and showed xylanase activity. Here, we describe the 3.88-Mb draft genome sequence of Anaerophaga sp. strain HS1 and the annotation analysis of related xylanase genes.  相似文献   
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