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941.
942.
Gyu-Nam Kim Young-Sool Hah Hyemin Seong Woong-Sun Yoo Mee-Young Choi Hee-Young Cho Seung Pil Yun Seong-Jae Kim 《International journal of molecular sciences》2021,22(12)
We investigated the role of nuclear factor of activated T cells 5 (NFAT5) under hyperosmotic conditions in human lens epithelial cells (HLECs). Hyperosmotic stress decreased the viability of human lens epithelial B-3 cells and significantly increased NFAT5 expression. Hyperosmotic stress-induced cell death occurred to a greater extent in NFAT5-knockout (KO) cells than in NFAT5 wild-type (NFAT5 WT) cells. Bcl-2 and Bcl-xl expression was down-regulated in NFAT5 WT cells and NFAT5 KO cells under hyperosmotic stress. Pre-treatment with a necroptosis inhibitor (necrostatin-1) significantly blocked hyperosmotic stress-induced death of NFAT5 KO cells, but not of NFAT5 WT cells. The phosphorylation levels of receptor-interacting protein kinase 1 (RIP1) and RIP3, which indicate the occurrence of necroptosis, were up-regulated in NFAT5 KO cells, suggesting that death of these cells is predominantly related to the necroptosis pathway. This finding is the first to report that necroptosis occurs when lens epithelial cells are exposed to hyperosmolar conditions, and that NFAT5 is involved in this process. 相似文献
943.
João Victor Barbosa Moura Antonio Amison Gomes de Souza Paulo de Tarso Cavalcante Freire Cleanio da Luz Lima Thiago Mielle Brito Ferreira Oliveira 《International Journal of Applied Ceramic Technology》2021,18(3):615-621
We report the structural, morphological, and optical characterization, and the application of sodium-cerium molybdate (NaCe(MoO4)2) as a promising photoelectroactive material for water splitting. Information on these several properties was obtained by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and UV–Vis–NIR diffuse reflectance. For the photoelectrochemical tests, NaCe(MoO4)2 microcrystals were deposited on conductive indium-tin oxide (ITO) glass substrate by drop coating, and the activity of the as-prepared photoanode toward oxygen evolution reaction was investigated in the absence and presence of blue light-emitting diode irradiation. Studies carried out by linear sweep voltammetry, chronoamperometry, and electrochemical impedance spectroscopy attested to a significant photoelectroactivity of molybdate associated with the fast electron-hole pairs generation. The steady-state photocurrent density recorded under irradiation achieved a remarkable increase, varying from 1.5 µA cm−2 (light off) to 44.1 µA cm−2 (light on), in addition, it presents high stability after on–off cycles, what proves the proper performance of NaCe(MoO4)2/ITO as photoanode for water splitting. 相似文献
944.
Dr. Guilherme F. S. Fernandes Dr. Débora L. Campos Dr. Isabel C. Da Silva Dr. João L. B. Prates Prof. Aline R. Pavan Prof. Fernando R. Pavan Prof. Jean L. Dos Santos 《ChemMedChem》2021,16(8):1268-1282
Tuberculosis (TB) is currently the leading cause of death related to infectious diseases worldwide, as reported by the World Health Organization. Moreover, the increasing number of multidrug-resistant tuberculosis (MDR-TB) cases has alarmed health agencies, warranting extensive efforts to discover novel drugs that are effective and also safe. In this study, 23 new compounds were synthesized and evaluated in vitro against the drug-resistant strains of M. tuberculosis. The compound 6-((3-fluoro-4-thiomorpholinophenyl)carbamoyl)benzo[c][1,2,5]oxadiazole 1-N-oxide ( 5 b ) was particularly remarkable in this regard as it demonstrated MIC90 values below 0.28 μM against all the MDR strains evaluated, thus suggesting that this compound might have a different mechanism of action. Benzofuroxans are an attractive new class of anti-TB agents, exemplified by compound 5 b , with excellent potency against the replicating and drug-resistant strains of M. tuberculosis. 相似文献
945.
Michael Ablinger Thomas Lettner Nicole Friedl Hannah Potocki Theresa Palmetzhofer Ulrich Koller Julia Illmer Bernadette Liemberger Stefan Hainzl Alfred Klausegger Manuela Reisenberger Jo Lambert Mireille Van Gele Eline Desmet Els Van Maelsaeke Monika Wimmer Roland Zauner Johann W. Bauer Verena Wally 《International journal of molecular sciences》2021,22(7)
Intermediate junctional epidermolysis bullosa caused by mutations in the COL17A1 gene is characterized by the frequent development of blisters and erosions on the skin and mucous membranes. The rarity of the disease and the heterogeneity of the underlying mutations renders therapy developments challenging. However, the high number of short in-frame exons facilitates the use of antisense oligonucleotides (AON) to restore collagen 17 (C17) expression by inducing exon skipping. In a personalized approach, we designed and tested three AONs in combination with a cationic liposomal carrier for their ability to induce skipping of COL17A1 exon 7 in 2D culture and in 3D skin equivalents. We show that AON-induced exon skipping excludes the targeted exon from pre-mRNA processing, which restores the reading frame, leading to the expression of a slightly truncated protein. Furthermore, the expression and correct deposition of C17 at the dermal–epidermal junction indicates its functionality. Thus, we assume AON-mediated exon skipping to be a promising tool for the treatment of junctional epidermolysis bullosa, particularly applicable in a personalized manner for rare genotypes. 相似文献
946.
Kyung Ho Min Shin Pil Kang Dae-Gun Kim Young Do Kim 《Journal of Alloys and Compounds》2005,400(1-2):150-153
Sintering characteristic of Al2O3-reinforced 2xxx series Al composite powders was investigated in order to obtain enhanced densification. In order to confirm the effect of the ceramic phase, Al composite powder, AMB 2905 (Al–3.2Cu–1.0Mg–5.0Al2O3), was used as the starting powder. Al blended powder, AMB 2712 (Al–3.8Cu–1.0Mg), was also used for comparison. The sintered density of the blended powder was about 93% of the theoretical value at 620 °C. The sintered density of the composite powder was about 95% at 630 °C. A small decrease in the density of each powder caused by swelling was observed after holding time of 10 min at the sintering temperature. After 20 min, the density slightly increased. The diffusion of the liquid phase was faster in the composite powder sintered specimen than in the blended powder sintered specimen. The liquid phase is thought to have infiltrated into the spaces between ceramic agglomerates. The results show that a greater amount of liquid phase is needed to enhance the sinterability of 2xxx series Al composite materials. 相似文献
947.
Ka Wing Ng Ralph Harris Albert E. Wraith Joël P. T. Kapusta Roberto Parra 《JOM Journal of the Minerals, Metals and Materials Society》2005,57(7):52-57
A cost model for the operation of copper converters is developed in this study, allowing an evaluation of the economic impact of changes to operating procedures and/or injection technologies. The model uses material and enthalpybalances for the slag and copper blows in a Peirce-Smith converter. The length of the converting cycle is calculated from the capacity of the blowers and the required blast along with the times required for other operations such as charging and skimming and idle time. Downtime, labor, and materials for converter lining repair as well as other costs such as oxygen enrichment are also considered in the cost calculations. The model is formulated in a spreadsheet using common programming language and is easily extended to examine the costs of alternative operating strategies or injection technologies such as high-pressure, shrouded injection. Example calculations showing the cost benefits of changing operating procedures and technology are presented. 相似文献
948.
Eduardo André Alberti Leandro João da Silva Ana Sofia C. M. D’Oliveira 《Welding International》2016,30(6):413-422
Additive manufacturing (AM) can be considered as an evolution from rapid prototyping as it allows us to manufacture a component from a computer file (CAD 3D), though its applications extrapolate the production of prototypes. This technique involves the layered design of a component and subsequent welding deposition of the multilayer structure to produce parts without the need of moulds or other tools. Although AM is frequently associated with the use of high density processes, the need for higher competitiveness expanded its range of technologies to include arc welding processes. This article aims to summarize up-to-date information on AM, particularly involving arc welding processes. Emphasis is given on the challenges associated with the building up of components during multilayered deposition and on post-deposition procedures. 相似文献
949.
Janka Vaková Beáta Velik Martina Pilátová Ivan Kron Ladislav Vako 何静 丁亚芳 杨静 李宝才 《腐植酸》2013,(2):32-37
腐植酸被认为在动物喂饲试验中对健康和产率具有整体积极作用,同时颇有争议的是,其也被作为肿瘤的病原学因素之一。我们尝试评价斯洛伐克地区特定来源腐植酸在使用推荐预防剂量时的体外作用。研究其体外的抗氧化性质、对肝线粒体中酶系和非酶系抗氧化防御系统的作用以及对人工培养肿瘤细胞株的作用。我们观察到不论腐植酸是溶解于二甲基亚砜(DMSO)或是直接加入呼吸介质中线粒体悬浮液,在腐植酸给药后超氧化物歧化酶(SOD)活性显著下降。所测定的其他抗氧化酶如谷胱甘肽过氧化物酶(GPx)和谷胱甘肽还原酶(GR),其活性及还原型谷胱甘肽(GSH)的含量与对照组相比并未表现出显著变化。腐植酸对超氧阴离子自由基(O2-·)的抑制率低于其对羟自由基(·OH)的抑制率。6种不同肿瘤细胞株的存活率显示出只有急性T淋巴性白血病细胞株对测试腐植酸敏感。尽管在水溶液中溶解度相对较低,但特定来源腐植酸参与了氧化还原调控。通过夺取自由基,腐植酸重置了抗氧化防御机制。来源于自然资源的腐植酸体外研究结果显示出其作为有前景的免疫增强剂的潜力。 相似文献
950.
A new on-line predictive monitoring and prediction model for periodic biological processes is proposed using the multiway non-Gaussian modeling. The basic idea of this approach is to use multiway non-Gaussian modeling to extract some dominant key components from daily normal operation data in a periodic process, and subsequently combining these components with predictive statistical process monitoring techniques. The proposed predictive monitoring method has been applied to fault detection and diagnosis in the biological wastewater-treatment process, which is based on strong diurnal characteristics. The results show the power and advantages of the proposed predictive monitoring of a continuous process using the multiway predictive monitoring concept, which is thus able to give very useful conceptual results for a daily monitoring process and also enables a more rapid detection of the process fault than other traditional monitoring methods. 相似文献