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Biochemistry (Moscow) - Many factors underlie the development of inflammatory bowel disease (IBD) in humans. In particular, imbalance of microbiota and thinning of the mucosal layer in the large...  相似文献   
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On the basis of 120 original stations, macrozoobenthic communities of rivers from two adjacent areas of the Lower Amur Region (Khabarovsk krai) have been described. Rivers basins are characterized by contrasting landscape conditions: the Anyuy River basin in the piedmonts of the Sikhote-Alin mountain range and the Simmi River basin on the Amur Lowland. About 250 taxa of macroinvertebrates have been found; 16 types of communities have been described. The principal differences in both benthic fauna and macrozoobenthic communities in the basins of the Anyuy River (cold-water rheophilic fauna as well as ritral and crenal communities predominate) and the Simmi River (warm-water limnophilic fauna and phytal communities predominate) are shown. We discuss the reasons for these differences, specific features of the fauna and communities of the whole region, and the biogeographical position of the region.  相似文献   
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BackgroundIron deficiency anemia (IDA) is the highest nutritional deficiency worldwide. It is a multifactorial disease, with a higher morbidity rate. TMPRSS6 polymorphisms importantly rs855791 is found to play an essential role in iron homeostasis in the human body. The rs855791 (T > C) polymorphism is highly associated with iron levels, and multiple blood parameters, leading to IDA. The role of TMPRSS6 rs855791 polymorphism and the significance of complete blood count (CBC) parameters in the pathogenesis of IDA is not yet studied in the Pakistani population.MethodsWe enrolled 113 cases and 136 controls to conduct a case control study. Complete blood count (CBC) and iron parameters were analyzed for association studies. PCR-RFLP based genotyping was performed.ResultsThe TMPRSS6 rs855791 (T > C) polymorphism is significantly associated with IDA pathogenesis as observed in the codominant model and recessive models (P < 0.05, OR: 1.5 and 95% CI: 0.9, 2.6, P < 0.05, OR: 0.5 and 95% CI: 0.2, 0.9 respectively). Elderly women among cases (30–49 years) were found to be more susceptible to IDA (P < 0.05, AOR: 2.1 and 95% CI: 1.0, 4.2). The most significant parameters associated with IDA were red blood cell count (RBC) and hematocrit (Hct%) (P < 0.05, AOR: 16.5, 95% CI: 7.6, 35.9 and P < 0.05, AOR: 10.1, 95% CI: 2.5, 41.6, respectively).ConclusionTMPRSS6 polymorphism at rs855791 (T > C) is significantly associated with IDA susceptibility in reproductive age women in Pakistan. Age, RBC count and Hct% are found to play an important role in IDA pathogenesis in our study population.  相似文献   
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Butanol, a fuel with better characteristics than ethanol, can be produced via acetone–butanol–ethanol (ABE) fermentation using lignocellulosic biomass as a carbon source. However, many inhibitors present in the hydrolysate limit the yield of the fermentation process. In this work, a detoxification technology combining flocculation and biodetoxification within a bacterial co-culture composed of Ureibacillus thermosphaericus and Cupriavidus taiwanensis is presented for the first time. Co-culture-based strategies to detoxify filtered and unfiltered hydrolysates have been investigated. The best results of detoxification were obtained for a two-step approach combining flocculation to biodetoxification. This sequential process led to a final phenolic compounds concentration of 1.4 g/L, a value close to the minimum inhibitory level observed for flocculated hydrolysate (1.1 g/L). The generated hydrolysate was then fermented with Clostridium acetobutylicum ATCC 824 for 120 h. A final butanol production of 8 g/L was obtained, although the detoxified hydrolysate was diluted to reach 0.3 g/L of phenolics to ensure noninhibitory conditions. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2753, 2019.  相似文献   
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The hydrophobic surfactant proteins SP-B and SP-C greatly accelerate the adsorption of vesicles containing the surfactant lipids to form a film that lowers the surface tension of the air/water interface in the lungs. Pulmonary surfactant enters the interface by a process analogous to the fusion of two vesicles. As with fusion, several factors affect adsorption according to how they alter the curvature of lipid leaflets, suggesting that adsorption proceeds via a rate-limiting structure with negative curvature, in which the hydrophilic face of the phospholipid leaflets is concave. In the studies reported here, we tested whether the surfactant proteins might promote adsorption by inducing lipids to adopt a more negative curvature, closer to the configuration of the hypothetical intermediate. Our experiments used x-ray diffraction to determine how the proteins in their physiological ratio affect the radius of cylindrical monolayers in the negatively curved, inverse hexagonal phase. With binary mixtures of dioleoylphosphatidylethanolamine (DOPE) and dioleoylphosphatidylcholine (DOPC), the proteins produced a dose-related effect on curvature that depended on the phospholipid composition. With DOPE alone, the proteins produced no change. With an increasing mol fraction of DOPC, the response to the proteins increased, reaching a maximum 50% reduction in cylindrical radius at 5% (w/w) protein. This change represented a doubling of curvature at the outer cylindrical surface. The change in spontaneous curvature, defined at approximately the level of the glycerol group, would be greater. Analysis of the results in terms of a Langmuir model for binding to a surface suggests that the effect of the lipids is consistent with a change in the maximum binding capacity. Our findings show that surfactant proteins can promote negative curvature, and support the possibility that they facilitate adsorption by that mechanism.  相似文献   
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