关键词： Calibration  

摘要： Species-specific isotope dilution mass spectrometry (SS-IDMS) has been the calibration method of choice for high accuracy speciation analysis because it can correct for detector sensitivity drifts, matrix effects, and analyte loss during sample preparation and analysis. However, in many cases SS-IDMS calibration is either not applicable (e.g. for monoisotopic elements) or not feasible (e.g. limited by the cost and availability of like-for-like isotopically enriched species). The work presented here demonstrates the potential of a novel on-column species-specific internal calibration approach, which is based on the chromatographic injection of the same species of the analyte as the internal standard (IS), after the sample injection. It can compensate for on-column analyte losses and signal drift and can be applied with any detector capable of recording time-resolved data, provided that enough species resolution can be achieved. The feasibility of this novel calibration strategy for accurate quantitative elemental speciation in complex matrices is demonstrated here through the analysis of inorganic arsenic in rice. An expanded uncertainty (k = 2) of <10% was obtained for a mass fraction range of 60 to 300 mu g kg(-1) inorganic-As (i-As) in dry rice products. The method is currently used for the certification of i-As in baby food matrices to support Commission Regulation (EU) 2015/1006 in regard to the maximum levels of i-As in foodstuffs.

关键词： ALPK1   cIAP1   NIK   TRAF  

摘要： Helicobacter pylori infection constitutes one of the major risk factors for the development of gastric diseases including gastric cancer. The activation of nuclear factor-kappa-light-chain-enhancer of activated B cells (NF-kappa B) via classical and alternative pathways is a hallmark of H. pylori infection leading to inflammation in gastric epithelial cells. Tumor necrosis factor receptor-associated factor (TRAF)-interacting protein with forkhead-associated domain (TIFA) was previously suggested to trigger classical NF-kappa B activation, but its role in alternative NF-kappa B activation remains unexplored. Here, we identify TRAF6 and TRAF2 as binding partners of TIFA, contributing to the formation of TIFAsomes upon H. pylori infection. Importantly, the TIFA/TRAF6 interaction enables binding of TGF beta-activated kinase 1 (TAK1), leading to the activation of classical NF-kappa B signaling, while the TIFA/TRAF2 interaction causes the transient displacement of cellular inhibitor of apoptosis 1 (cIAP1) from TRAF2, and proteasomal degradation of cIAP1, to facilitate the activation of the alternative NF-kappa B pathway. Our findings therefore establish a dual function of TIFA in the activation of classical and alternative NF-kappa B signaling in H. pylori-infected gastric epithelial cells.

关键词： Tropical malaria   Plasmodium falciparum   Covalent inhibitor   Ferredoxin   Reductase   Enzyme kinetics  

摘要： The protozoan Plasmodium falciparum is the main aetiological agent of tropical malaria. Characteristic of the phylum is the presence of a plastid-like organelle which hosts several homologs of plant proteins, including a ferredoxin (PfFd) and its NADPH-dependent reductase (PfFNR). The PfFNR/PfFd redox system is essential for the parasite, while mammals share no homologous proteins, making the enzyme an attractive target for novel and much needed antimalarial drugs. Based on previous findings, three chemically reactive residues important for PfFNR activity were identified: namely, the active-site Cys99, responsible for hydride transfer;Cys284, whose oxidation leads to an inactive dimeric form of the protein;and His286, which is involved in NADPH binding. These amino acid residues were probed by several residue-specific reagents and the two cysteines were shown to be promising targets for covalent inhibition. The quantitative and qualitative description of the reactivity of few compounds, including a repurposed drug, set the bases for the development of more potent and specific antimalarial leads. (c) 2021 Elsevier Inc. All rights reserved.

关键词： Cancer genetics   Cancer genomics  

摘要： Great progress has been made in the investigation on mutation and expression of splicing factor. However, little is known on the role of alternative splicing of splicing factors across cancers. Here, we reported a pan-cancer analysis of alternative splicing of splicing factors spanning 6904 patients across 16 cancer types, and identified 167 splicing factors with implications regulating cancer-specific splicing patterns through alternative splicing. Furthermore, we found that abnormal splicing events of splicing factors could serve as potential common regulators for alternative splicing in different cancers. In addition, we developed a splicing-derived neoepitopes database (ASPNs), which provided the corresponding putative alternative splicing-derived neoepitopes of 16 cancer types. Our results suggested that alternative splicing of splicing factors involved in the pre-RNA splicing process was common across cancer types and may represent an underestimated hallmark of tumorigenesis.

关键词： Sensors   Liquids   Sound velocity   Fossil fuels   Fuels  

摘要： The use of jet fuels in compression-ignition engines with pump-line-nozzle (PLN) fuel injection systems requires consideration of differences in bulk modulus and speed of sound versus diesel fuels, thus requiring thorough characterization of jet fuels before they are applied. In this study, we measured the isothermal bulk modulus of compressibility of three different petroleum-based jet fuels (i.e., POSF 4658, POSF 6169, and POSF 10325) at 313 K (0-4000 psig) and of three different alternative jet fuels (i.e., Farnesane, hydrotreated renewable jet-derived from Camelina (HRJC), and Alcohol-to-Jet (ATJ)) at 308 K (0-4000 psig). Measured isothermal bulk modulus is used to calculate the specific heat ratio of each test fuel by comparing it to the isentropic bulk modulus referenced from previous literature. Measurement results show that the bulk modulus of petroleum-based jet fuels is similar to 20%-25% lower than that of the petroleum-based diesel fuel: 984, 932, and 953 MPa for POSF 4658, POSF 6169, and POSF 10325, respectively, at 0.1 MPa. The bulk modulus of Farnesane (982 MPa at 0.1 MPa) was similar to that of petroleum-based jet fuels while those of the other alternative jet fuels were similar to 4% (HRJC) and 14% (ATJ) lower than that of the petroleum jet fuels. We also measured the pseudoisothermal speed of sound of these jet fuels using a pair of fuel line pressure sensors installed on the fuel supply line of a diesel engine in a temperature range between 318 K and 338 K. Results showed a lower pseudoisothermal speed of sound for both petroleum-based (1114-1122 m/s at 328 K) and alternative jet fuels (1038-1116 m/s at 328 K) relative to petroleum-based diesel fuel. Isentropic speed of sound estimated by applying the conversion factor to the pseudoisothermal speed of sound measurement showed a similar trend: a lower isentropic speed of sound for jet fuels relative to petroleum-based diesel fuel. This suggested an unintended retarding in the actual fuel injection

关键词： 抑郁症   帕罗西汀   重复经颅磁刺激   认知行为疗法   无抽搐电休克  

摘要： 抑郁症(MDD)在当代社会已是一种较为常见的精神疾病,发病机制虽不明确,但有多种学说。临床治疗抑郁症仍采用药物疗法,虽然疗效确切但不良反应问题也同样突出。近年来发展的非药物疗法以其非侵入性、安全、无副作用的特点成为治疗抑郁症的辅助手段,帮助药物获得更好的临床效果。本文以帕罗西汀联合的其他疗法为例,列举近年常用的非药物疗法,以期为临床治疗抑郁症提供新方法和新思路。

关键词： 利尿药   高血压   联合用药   临床进展  

摘要： 近年来,根据国内流行病理学的调查,我国慢性高血压患者中的发病原因逐渐增加,且呈年轻化的趋势,因此关于慢性高血压疾病的研究、治疗及其预防仍是当下医学界研究的热点。利尿剂可以作为体内的离子再吸收抑制剂,可以有效抑制体内离子在体内的再吸收,从而有效地降低高血压,并通过联合使用可以有效减少其他降压药的副作用,因此在临床实践中得到广泛应用。本文就近年来利尿剂联合其他降压药物治疗高血压的临床疗效作一综述。

关键词： 敖拉·昌兴   杜甫   唐代诗人  

摘要： 清代达斡尔族诗人敖拉·昌兴在《看年画》《劝世歌》诗歌中赞美杜甫诗才,感慨杜甫有志难酬,表达了对杜甫的赞赏与同情。他还在《看年画》《百花诗》《善恶篇》等诗歌中,赞颂李白、孟浩然、韩愈、白居易等唐代诗人。本文通过探究敖拉·昌兴对杜甫及其他唐代诗人的接受因素,发现他学习唐诗是以广泛的汉文化为基础,并且受到了清代尊唐诗学思潮的影响。

关键词： 交通运输   其他产业   融合特征  

摘要： 交通运输行业是我国重要的服务性行业,在国民经济中占据着基础性、先导性与战略性地位,推进交通运输与其他产业的融合发展已成为新时期交通运输转型升级、优化产业结构、转换增长动力的必然要求。从新时期交通运输与其他产业融合的定义出发,分析了新时期交通运输与其他产业融合的发展利好因素,探讨了新时期交通运输与其他产业融合的特征,并尝试提出了新时期促进交通运输与其他产业融合的若干建议,希望对新时期交通运输与其他产业融合提供一定的参考。