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161.
Yuanyuan Pan Minghuan Fu Xiaohan Chen Jing Guo Biao Chen Xuefei Tao 《Journal of cellular and molecular medicine》2020,24(17):9890-9897
Methionine restrictive diet may alleviate ischaemia/reperfusion (I/R)‐induced myocardial injury, but its underlying mechanism remains unclear. HE staining was performed to evaluate the myocardial injury caused by I/R and the effect of methionine‐restricted diet (MRD) in I/R mice. IHC and Western blot were carried out to analyse the expression of CSE, CHOP and active caspase3 in I/R mice and hypoxia/reoxygenation (H/R) cells. TUNEL assay and flow cytometry were used to assess the apoptotic status of I/R mice and H/R cells. MTT was performed to analyse the proliferation of H/R cells. H2S assay was used to evaluate the concentration of H2S in the myocardial tissues and peripheral blood of I/R mice. I/R‐induced mediated myocardial injury and apoptosis were partially reversed by methionine‐restricted diet (MRD) via the down‐regulation of CSE expression and up‐regulation of CHOP and active caspase3 expression. The decreased H2S concentration in myocardial tissues and peripheral blood of I/R mice was increased by MRD. Accordingly, in a cellular model of I/R injury established with H9C2 cells, cell proliferation was inhibited, cell apoptosis was increased, and the expressions of CSE, CHOP and active caspase3 were dysregulated, whereas NaHS treatment alleviated the effect of I/R injury in H9C2 cells in a dose‐dependent manner. This study provided a deep insight into the mechanism underlying the role of MRD in I/R‐induced myocardial injury. 相似文献
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Xiaojiao Zeng Guohong Liu Yunbao Pan Yirong Li 《Journal of cellular and molecular medicine》2020,24(15):8326-8349
Inflammation indicators, such as systemic inflammation response index (SIRI), systemic immune‐inflammation index (SII), neutrophil‐to‐lymphocyte ratio (NLR) and platelet‐lymphocyte ratio (PLR), are associated with poor prognosis in various solid cancers. In this study, we investigated the predictive value of these inflammation indicators in nasopharyngeal carcinoma (NPC). This retrospective study involved 559 patients with NPC and 500 patients with chronic rhinitis, and 255 NPC patients were followed up successfully. Continuous variables and qualitative variables were measured by t test and chi‐square test, respectively. The optimal cut‐off values of various inflammation indicators were determined by receiver operating characteristic (ROC) curve. Moreover, the diagnostic value for NPC was decided by the area under the curves (AUCs). The Kaplan‐Meier methods and the log‐rank test were used to analyse overall survival (OS) and disease‐free survival (DFS). The independent prognostic risk factors for survival and influencing factors of side effects after treatment were analysed by Cox and logistic regression analysis, respectively. Most haematological indexes of NPC and rhinitis were significantly different between the two groups, and PLR was optimal predictive indicators of diagnosis. In the multivariable Cox regression analysis, PLR, WBC, RDW, M stage and age were independent prognostic risk factors. Many inflammation indicators that affected various side effects were evaluated by logistic regression analysis. In conclusion, the combined inflammation indicators were superior to single haematological indicator in the diagnosis and prognosis of NPC. These inflammation indicators can be used to supply the current evaluation system of the TNM staging system to help predict the prognosis in NPC patients. 相似文献
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Selective CO2 reduction to formic acid or formate is the most technologically and economically viable approach to realize electrochemical CO2 valorization. Main group metal–based (Sn, Bi, In, Pb, and Sb) nanostructured materials hold great promise, but are still confronted with several challenges. Here, the current status, challenges, and future opportunities of main group metal–based nanostructured materials for electrochemical CO2 reduction to formate are reviewed. Firstly, the fundamentals of electrochemical CO2 reduction are presented, including the technoeconomic viability of different products, possible reaction pathways, standard experimental procedure, and performance figures of merit. This is then followed by detailed discussions about different types of main group metal–based electrocatalyst materials, with an emphasis on underlying material design principles for promoting the reaction activity, selectivity, and stability. Subsequently, recent efforts on flow cells and membrane electrode assembly cells are reviewed so as to promote the current density as well as mechanistic studies using in situ characterization techniques. To conclude a short perspective is offered about the future opportunities and directions of this exciting field. 相似文献
166.
Changjian Zuo Zongxiang Hu Rui Qi Jiajie Liu Zhibo Li Junliang Lu Cheng Dong Kai Yang Weiyuan Huang Cong Chen Zhibo Song Sicheng Song Yaoming Yu Jiaxin Zheng Feng Pan 《Liver Transplantation》2020,10(34)
The relatively low capacity and capacity fade of spinel LiMn2O4 (LMO) limit its application as a cathode material for lithium‐ion batteries. Extending the potential window of LMO below 3 V to access double capacity would be fantastic but hard to be realized, as it will lead to fast capacity loss due to the serious Jahn–Teller distortion. Here using experiments combined with extensive ab initio calculations, it is proved that there is a cooperative effect among individual Jahn–Teller distortions of Mn3+O6 octahedrons in LMO, named as cooperative Jahn–Teller distortion (CJTD) in the text, which is the difficulty to access the capacity beyond one lithium intercalation. It is further proposed that the cationic disordering (excess Li at Mn sites and Li/Mn exchange) can intrinsically suppress the CJTD of Mn3+O6 octahedrons. The cationic disordering can break the symmetry of Mn3+ arrangements to disrupt the correlation of distortions arising from individual JT centers and prevent the Mn3+? O bonds distorting along one direction. Interestingly, with the suppressed CJTD, the original octahedral vacancies in spinel LMO are activated and can serve as extra Li‐ion storage sites to access the double capacity with good reversible cycling stability in microsized LMO. 相似文献
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目的:既往研究发现,趋化因子CCL20在银屑病、白癜风等在内的多种自身免疫性皮肤疾病的病理过程中扮演了重要的角色,同时病毒感染也被认为是自身免疫性疾病的重要参与者。皮肤组织是机体抵御外界病原体的第一道屏障,其中角质形成细胞被认为在启动免疫中发挥了关键的作用。视黄酸诱导基因蛋白I(RIG-I)是固有免疫模式识别受体家族的重要成员,其能够被病毒复制的中间产物激活。然而,病毒感染是否会通过RIG-I信号通路影响角质形成细胞中CCL20的表达,进而参与自身免疫性皮肤疾病的病理过程仍不清楚。本文使用聚肌胞苷酸(Poly(I:C))来体外模拟病毒感染,探究病毒感染对皮肤角质形成细胞CCL20表达的影响,并且通过小干扰RNA沉默关键分子来探究相应的分子机制。方法:首先,体外细胞实验使用Poly(I:C)刺激角质形成细胞系HaCaT,通过Western-blot实验和qRT-PCR实验探究Poly(I:C)对HaCat中RIG-I表达的影响;接下来,通过实时荧光定量PCR(qRT-PCR)以及酶联免疫吸附测定实验(ELISA)检测Poly(I:C)对角质形成细胞CCL20分泌的影响;线粒体抗病毒信号蛋白(MAVS)在RIG-I的下游发挥着重要作用,我们通过小干扰RNA(si-RNA)阻断RIG-I-MAVS-NF-κB信号通路关键分子,探究Poly(I:C)诱导角质形成细胞CCL20表达升高的分子机制。结果:Poly(I:C)能够明显促进角质形成细胞中RIG-I的表达及CCL20的表达和分泌;Poly(I:C)诱导角质形成细胞CCL20分泌是由RIG-I-MAVS-NF-κB信号通路介导的。结论:Poly(I:C)模拟病毒感染能够通过RIG-I-MAVS-NF-κB信号通路介导CCL20表达增加,进而参与自身免疫性皮肤疾病的病理过程。 相似文献
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豆天蛾Clanis bilineata tsingtauica Mell幼虫,是一种食用昆虫,富含蛋白质、维生素和矿质元素,具有很高的营养、药用和经济价值。了解适宜豆天蛾幼虫生长发育的大豆品种(品系)和种植密度,可为豆天蛾幼虫规模化饲养提供理论基础。研究通过设置两因素裂区实验,在10个品种(品系)大豆和2个种植密度水平下,测定豆天蛾幼虫生物学参数,明确适宜豆天蛾幼虫养殖的大豆品种(品系)和种植密度。结果表明,不同大豆品种(系)和种植密度对豆天蛾幼虫存活及生长发育均有显著影响;其中使用连151、淮豆9号、东辛3号和H0573大豆饲养的豆天蛾幼虫产量和存活率较高,虫体长度较长,发育历期较短;大青豆饲养的豆天蛾幼虫产量较低,幼虫发育整齐度较差,发育历期长。当种植密度为40 cm×30 cm时,豆天蛾幼虫存活和发育历期整齐度均显著高于种植密度40 cm×15 cm。综上所述,较适宜豆天蛾幼虫养殖的大豆品种(品系)为连151、淮豆9号、东辛3号和H0573,种植密度为40 cm×30 cm。 相似文献