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Xinghai Zhang Shaohong Chen Zengguo Cao Yanfeng Yao Junping Yu Junhui Zhou Ge Gao Ping He Zhuo Dong Jie Zhong Jing Luo Hongping Wei Huajun Zhang 《中国病毒学》2022,37(6):796-803
During the two-year pandemic of coronavirus disease 2019 (COVID-19), its causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been evolving. SARS-CoV-2 Delta, a variant of concern, has become the dominant circulating strain worldwide within just a few months. Here, we performed a comprehensive analysis of a new B.1.617.2 Delta strain (Delta630) compared with the early WIV04 strain (WIV04) in vitro and in vivo, in terms of replication, infectivity, pathogenicity, and transmission in hamsters. When inoculated intranasally, Delta630 led to more pronounced weight loss and more severe disease in hamsters. Moreover, 40% mortality occurred about one week after infection with 104 PFU of Delta630, whereas no deaths occurred even after infection with 105 PFU of WIV04 or other strains belonging to the Delta variant. Moreover, Delta630 outgrew over WIV04 in the competitive aerosol transmission experiment. Taken together, the Delta630 strain showed increased replication ability, pathogenicity, and transmissibility over WIV04 in hamsters. To our knowledge, this is the first SARS-CoV-2 strain that causes death in a hamster model, which could be an asset for the efficacy evaluation of vaccines and antivirals against infections of SARS-CoV-2 Delta strains. The underlying molecular mechanisms of increased virulence and transmission await further analysis. 相似文献
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Potassium inwardly rectifying channel, subfamily-J, member 11 (KCNJ11) gene encodes Kir6.2 subunits of the adenosine triphosphate (ATP)-sensitive potassium channel involved in glucose-mediated metabolic signaling pathway and has attracted considerable attention as a candidate gene for type 2 diabetes (T2D) based on its function in glucose-stimulated insulin secretion. In the past decade, a number of case-control studies have been conducted to investigate the relationship between the KCNJ11 polymorphisms and T2D. However, these studies have yielded contradictory results. To investigate this inconsistency and derive a more precise estimation of the relationship, we conducted a comprehensive meta-analysis of 64,403 cases and 122,945 controls from 49 published studies. Using the random-effects model, we found a significant association between E23K (rs5219) polymorphism and T2D risk with per-allele odds ratio of 1.13 (95% confidence interval: 1.10-1.15; p<10(-5)). Significant results were found in East Asians and Caucasians when stratified by ethnicity; whereas no significant associations were found among South Asians and other ethnic populations. In subgroup analysis by sample size, mean age and body mass index (BMI) of cases, mean BMI of controls and diagnostic criterion, significantly increased risks were found in all genetic models. This meta-analysis suggests that the E23K polymorphism in KCNJ11 is associated with elevated T2D risk, but these associations vary in different ethnic populations. 相似文献
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高温干旱季节红壤丘陵果园杂草保持的生态作用 总被引:21,自引:0,他引:21
研究了红壤丘陵果园杂草保持在高温干旱期的生态作用。结果表明。高温伏早期幼龄果园没有杂草覆盖或覆盖度很低的处理(人工除草和除草剂除草),土壤温度明显高于保留杂草的处理(不除草、刈割、保留低矮草带),而土壤湿度、土壤微生物生物量碳、解磷微生物解磷活性、土壤VA菌根真菌的数量则低于保留杂草的处理。在杂草保留的3个处理中,虽然土壤温度、土壤微生物生物量碳、解磷微生物解磷活性差异不显著,但不除草的处理,高大的杂草与幼龄果树对光产生竞争,从而影响了果树的生长,因而建议在幼龄果园以刈割或保留草带的方式保持杂草。 相似文献
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Xinghai Cheng Lin Gan Jing Zhao Minhao Chen Yang Liu Youhua Wang 《Neurochemical research》2013,38(5):1013-1021
Ataxin-10 is a cytoplasmic protein that belongs to the family of armadillo repeat proteins and the ataxin proteins are ubiquitously expressed in nervous tissue. A loss of Ataxin-10 in primary neuronal cells causes increased apoptosis of cerebellar neurons. Knockdown of ATXN10 with siRNA in HeLa cells results in cytokinesis defects-multinucleation. Because of the essential role of Ataxin-10 in nervous system and cellular cytokinesis, we investigated the spatiotemporal expression of Ataxin-10 in a rat sciatic nerve crush (SNC) model. After never injury, we observed that Ataxin-10 had a significant up-regulation from 3d, peaked at day 5 and then gradually decreased to the normal level at 4 weeks. At its peak expression, Ataxin-10 expressed mainly in Schwann cells and macrophages of the distal sciatic nerve segment from injury, but had few co-localizations in axons. Besides, the peak expression of Ataxin-10 was in parallel with proliferating cell nuclear antigen (PCNA), and Ataxin-10 co-labeled with PCNA. Thus, all of our findings suggested that Ataxin-10 may be involved in the pathophysiology of sciatic nerve after SNC. 相似文献
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Design,synthesis and fungicidal activity of novel 2-substituted aminocycloalkylsulfonamides 总被引:2,自引:0,他引:2
Caixiu Liu Xiaojing Yan Minlong Wang Peiwen Qin Zhiqiu Qi Mingshan Ji Xingyu Liu P. Vijaya Babu Xinghai Li Zi-Ning Cui 《Bioorganic & medicinal chemistry letters》2017,27(2):271-276
A series of novel 2-substituted aminocycloalkylsulfonamides were designed and synthesized by highly selective N-alkylation reaction, whose structures were characterized by 1H NMR, 13C NMR and HRMS. Among them, the configuration of compounds III12 and III20 were confirmed by X-ray single crystal diffraction. Bioassays demonstrated that the title compounds had considerable effects on different strains of Botrytis cinerea and Pyricularia grisea. Comparing with positive control procymidone (EC50 = 10.31 mg/L), compounds III28, III29, III30 and III31 showed excellent fungicidal activity against a strain of B. cinerea (CY-09), with EC50 values of 3.17, 3.04, 2.54 and 1.99 mg/L respectively. Their in vivo fungicidal activities were also better than the positive controls cyprodinil, procymidone, boscalid and carbendazim in pot experiments. Moreover, the fungicidal activity of III28 (EC50 = 4.62 mg/L) against P. grisea was also better than that of the positive control isoprothiolane (EC50 = 6.11 mg/L). Compound III28 would be great promise as a hit compound for further study based on the structure-activity relationship. 相似文献
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运动对大鼠血小板L—精氨酸转运的影响 总被引:10,自引:0,他引:10
本工作在游泳大鼠模型上,观察血小板L-精氨酸(L-Arg)转运特征,并观察凝血酶和PAF对血小板L-Arg转运的影响。结果发现,运动大鼠血小板L-Arg转运明显高于未运动对照大鼠,表现在高亲和性最大转运速率(Vmax)明显增高(50.56±3.27pmol/108vs45.84±2.36pmol/108血小板/min。P<0.05),米氏常数亦显著增加(2.14±0.23μmol/Lvs1.46±0.13μmol/L,P<0.01)。应用刺激剂凝血酶和PAF诱导运动大鼠血小板L-Arg转运速率增加的幅度明显高于未运动对照大鼠(P<0.01)。实验结果表明,运动能增强血小板转运L-Arg的效率。提示,运动可能促进血小板一氧化氮(NO)生成,抑制血小板聚集,防治血管栓塞性疾病 相似文献
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Protein phosphatase 2A (PP2A) is an abundant heterotrimeric serine/threonine phosphatase containing highly conserved structural (A) and catalytic (C) subunits. Its diverse functions in the cell are determined by its association with a highly variable regulatory and targeting B subunit. At least three distinct gene families encoding B subunits are known: B/B55/CDC55, B'/B56/RTS1 and B"/PR72/130. No homology has been identified among the B families, and little is known about how these B subunits interact with the PP2A A and C subunits. In vitro expression of a series of B56alpha fragments identified two distinct domains that bound independently to the A subunit. Sequence alignment of these A subunit binding domains (ASBD) identified conserved residues in B/B55 and PR72 family members. The alignment successfully predicted domains in B55 and PR72 subunits that similarly bound to the PP2A A subunit. These results suggest that these B subunits share a common core structure and mode of interaction with the PP2A holoenzyme. 相似文献