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991.
Adzuki seed β-vignin, a vicilin-like globulin, has proven to exert various health-promoting biological activities, notably in cardiovascular health. A simple scalable enrichment procedure of this protein for further nutritional and functional studies is crucial. In this study, a simplified chromatography-independent protein fractionation procedure has been optimized and described. The electrophoretic analysis showed a high degree of homogeneity of β-vignin isolate. Furthermore, the molecular features of the purified protein were investigated. The adzuki bean β-vignin was found to have a native size of 146 kDa, and the molecular weight determined was consistent with a trimeric structure. These were identified in two main polypeptide chains (masses of 56–54 kDa) that are glycosylated polypeptides with metal binding capacity, and one minor polypeptide chain with a mass 37 kDa, wherein these features are absent. The in vitro analysis showed a high degree of digestibility of the protein (92%) and potential anti-inflammatory capacity. The results lay the basis not only for further investigation of the health-promoting properties of the adzuki bean β-vignin protein, but also for a possible application as nutraceutical molecule.  相似文献   
992.
Glioblastoma (GBM) is known to be the most common and lethal primary malignant brain tumor. Therapies against this neoplasia have a high percentage of failure, associated with the survival of self-renewing glioblastoma stem cells (GSCs), which repopulate treated tumors. In addition, despite new radical surgery protocols and the introduction of new anticancer drugs, protocols for treatment, and technical advances in radiotherapy, no significant improvement in the survival rate for GBMs has been realized. Thus, novel antitarget therapies could be used in conjunction with standard radiochemotherapy approaches. Targeted therapy, indeed, may address specific targets that play an essential role in the proliferation, survival, and invasiveness of GBM cells, including numerous molecules involved in signal transduction pathways. Significant cellular heterogeneity and the hierarchy with GSCs showing a therapy-resistant phenotype could explain tumor recurrence and local invasiveness and, therefore, may be a target for new therapies. Therefore, the forced differentiation of GSCs may be a promising new approach in GBM treatment. This article provides an updated review of the current standard and experimental therapies for GBM, as well as an overview of the molecular characteristics of GSCs, the mechanisms that activate resistance to current treatments, and a new antitumor strategy for treating GSCs for use as therapy.  相似文献   
993.
994.
Hispanics are disproportionally affected by liver fibrosis and hepatocellular carcinoma (HCC). Advanced liver fibrosis is a major risk factor for HCC development. We aimed at identifying somatic mutations in plasma cell-free DNA (cfDNA) of Hispanics with HCC and Hispanics with advanced liver fibrosis but no HCC. Targeted sequencing of over 262 cancer-associated genes identified nonsynonymous mutations in 22 of the 27 HCC patients. Mutations were detected in known HCC-associated genes (e.g., CTNNB1, TP53, NFE2L2, and ARID1A). No difference in cfDNA concentrations was observed between patients with mutations and those without detectable mutations. HCC patients with higher cfDNA concentrations or higher number of mutations had a shorter overall survival (p < 0.001 and p = 0.045). Nonsynonymous mutations were also identified in 17 of the 51 subjects with advanced liver fibrosis. KMT2C was the most commonly mutated gene. Nine genes were mutated in both subjects with advanced fibrosis and HCC patients. Again, no significant difference in cfDNA concentrations was observed between subjects with mutations and those without detectable mutations. Furthermore, higher cfDNA concentrations and higher number of mutations correlated with a death outcome in subjects with advanced fibrosis. In conclusion, cfDNA features are promising non-invasive markers for HCC risk prediction and overall survival.  相似文献   
995.
Vibrio cholerae is well recognized as the causative agent of cholera, an acute intestinal infection characterized by watery diarrhea that may lead to dehydration and death in some cases. V. cholerae is a natural inhabitant of the aquatic environment in the tropical regions. Jakarta has the highest percentage of individuals affected by sporadic diarrheal illness compared with other areas in Indonesia. Inadequate safety measures for drinking water supplies, improper sanitation, and poor hygiene can increase the risk of cholera outbreaks. Few studies have been conducted on the prevalence of these bacteria in ice and beverages that are popularly sold and consumed in Jakarta. In this study, we detected and quantified V. cholerae from ice and beverages collected from several areas in five regions of Jakarta. Levels of V. cholerae in both ice and beverages were determined with the three-tube most-probable-number (MPN) method and ranged from < 0.3 to > 110 MPN/ml. The presence of regulatory and virulence gene sequences was determined by using uniplex and multiplex PCR assays. Of 110 samples tested, 33 (30%) were positive for V. cholerae; 21 (64%) were ice samples and the remaining 12 (36%) were beverages. A total of 88 V. cholerae strains were isolated, based on the presence of the toxR gene sequence identified by PCR. Other genetic markers, such as hlyA (59%), ompU (16%), and ctxA (19%), also were found during the search for potential pathogenic strains. The detection and isolation of potentially harmful V. cholerae from ice and beverages in Jakarta indicate that these products pose a health risk from choleragenic vibrios, particularly because of the emergence of classical biotypes of V. cholerae O1 and potentially harmful non-O1 serovars of this species.  相似文献   
996.
The effect of 0.3 wt pct Na on the microstructure of extruded alloy Mg-2Sn-1Zn is examined. We report that Na stabilizes the Mg2Sn phase, resulting in its precipitation during extrusion under conditions where a solid solution is otherwise expected. This effect appears to be thermodynamic in nature and is different from the kinetic enhancement of low- temperature aging reported by Mendis et al. [Phil. Mag. Letters, 86 (2006), 443]. The precipitates of the current study enable useful refinement of the grain size.  相似文献   
997.
Predicting and mitigating human error in manned spaceflight can be the difference between mission success and lost vehicle or crewmember. The National Aeronautics and Space Administration (NASA) has used the Cognitive Reliability Error Analysis Model analysis developed by the nuclear industry during the last 30 years of manned spaceflight to predict human error. Although the analysis has proven to be reliable, it does not take into account operations specific for long duration spaceflight such as crew training and ground support. This article first explains the principles of the Cognitive Reliability Error Analysis Model and how it is used at NASA. Then, the probability for error for an International Space Station ingress procedure is calculated using standard performance shaping factors developed for the nuclear power industry. Lastly, the environmental and operational constraints of space flight are used to develop new performance shaping factors specific to a NASA‐operated spacecraft. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
998.
A series of air‐stable, nitrile‐ligated (cyclopentadienone)iron dicarbonyl compounds was synthesized and their activities as catalysts in the transfer reduction of acetophenone were explored. While all were active catalysts, the acetonitrile adduct was chosen for further study and was found to be active in the transfer reduction of aldehydes and ketones and in the Oppenauer‐type oxidation of secondary alcohols. The acetonitrile catalyst exhibited activities similar to those of an analogous air‐sensitive iron hydride, but unlike the iron hydride it was unreactive in carbonyl reductions using hydrogen gas.  相似文献   
999.
河内博物馆     
穿过园林景观来访者可从四个方向进入博物馆。在正方形的建筑体中庭内,一座圆形的挑空大厅将入口层面于其上的三层展览空间连接起来。如同倒置的金字塔般,中庭向上呈阶梯状展开。来访者向外望去,仿佛"漂浮"于主题公园景观之上。盘旋上升的坡道作为极富表现力的空间元素,将人们吸引至建筑顶部,并且实现了展览空间与中庭的视线交流。由于展览空间全部安排在建筑的首层至三层,会议、科研中心,办公空间以  相似文献   
1000.
Microbiological characterizations of contaminant biodegradation in fractured sedimentary rock have primarily focused on the biomass suspended in groundwater samples and disregarded the biomass attached to fractures and in matrix pores. In fractured sedimentary rock, diffusion causes nearly all contaminant mass to reside in porous, low-permeability matrix. Microorganisms capable of contaminant degradation can grow in the matrix pores if the pores and pore throats are sufficiently large. In this study, the presence of dechlorinating microorganisms in rock matrices was investigated at a site where a fractured, flat-lying, sandstone-dolostone sequence has been contaminated with a mixture of chlorinated and aromatic hydrocarbons for over 40 years. The profile of organic contaminants as well as the distribution and characterization of the microbial community spatial variability was obtained through depth-discrete, high-frequency sampling along a 98-m continuous rock core. Dechlorinating microorganisms, such as Dehalococcoides and Dehalobacter, were detected in the rock matrices away from fracture surfaces, indicating that biodegradation within the rock matrix blocks should be considered as an important component of the system when evaluating the potential for natural attenuation or remediation at similar sedimentary rock sites.  相似文献   
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