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161.
Dong  Haoru  Shu  Xinhua  Xu  Qiang  Zhu  Chen  Kaufmann  Andreas M.  Zheng  Zhi-Ming  Albers  Andreas E.  Qian  Xu 《中国病毒学》2021,36(6):1284-1302
Virologica Sinica - Human papillomavirus (HPV) infection identified as a definitive human carcinogen is increasingly being recognized for its role in carcinogenesis of human cancers. Up to...  相似文献   
162.
Wan  Qiangyou  Kong  Deping  Liu  Qian  Guo  Shumin  Wang  Chenchen  Zhao  Yan  Ke  Zun-Ji  Yu  Ying 《中国科学:生命科学英文版》2021,64(7):1068-1076
Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit prostaglandin (PG) formation by targeting cyclooxygenase (COX) 1 and 2.Long-term use of NSAIDs that selectively inhibit COX2 increases the risk for thrombotic events,cardiac failure,and hypertension.However,the underlying mechanisms remain unclear.In this study,COX1- and COX2-deficient rats were created via Cas9/RNA-mediated gene targeting.DNA genotyping and Western blot analysis confirmed successful generation of COX1~(-/-)and COX2~(-/-)rats.Adult COX1~(-/-)rats grew normally,while more than 70%of COX2~(-/-)rats after wean died within 2 months.Echocardiography showed markedly reduced left ventricular ejection fraction and fractional shortening in adult COX2~(-/-)rats compared to those in wildtype (WT) controls.Histological analysis revealed accumulation of inflammatory cells and severe interstitial and perivascular fibrosis in COX2~(-/-)cardiac tissues.Moreover,cardiac ATP and acetyl-Co A production was dramatically decreased in COX2~(-/-)rats.Consistently,the expression of genes related to mitochondrial oxidation,such as those that encode for subunits of pyruvate dehydrogenase complex and acyl Co A dehydrogenases,were downregulated,while glycolytic hexokinase 1 (HK1) was upregulated in COX2~(-/-)heart tissues.These observations indicate that COX2-deficient rats developed spontaneously heart failure,likely as a result of dysregulated cardiac energy metabolism.  相似文献   
163.
Grain size is determined by the size and number of cells in the grain. The regulation of grain size is crucial for improving crop yield; however, the genes and molecular mechanisms that control grain size remain elusive. Here, we report that a member of the detoxification efflux carrier /Multidrug and Toxic Compound Extrusion (DTX/MATE) family transporters, BIG RICE GRAIN 1 (BIRG1), negatively influences grain size in rice (Oryza sativa L.). BIRG1 is highly expressed in reproductive organs and roots. In birg1 grain, the outer parenchyma layer cells of spikelet hulls are larger than in wild-type (WT) grains, but the cell number is unaltered. When expressed in Xenopus laevis oocytes, BIRG1 exhibits chloride efflux activity. Consistent with this role of BIRG1, the birg1 mutant shows reduced tolerance to salt stress at a toxic chloride level. Moreover, grains from birg1 plants contain a higher level of chloride than those of WT plants when grown under normal paddy field conditions, and the roots of birg1 accumulate more chloride than those of WT under saline conditions. Collectively, the data suggest that BIRG1 in rice functions as a chloride efflux transporter that is involved in mediating grain size and salt tolerance by controlling chloride homeostasis.  相似文献   
164.
目的:探讨盆腔瘀血综合征患者彩色多普勒超声的影像学特征及与临床因素的相关性。方法:对112例盆腔瘀血综合征患者行彩色多普勒超声检查,按超声诊断分级Ⅰ级、Ⅱ级、Ⅲ级分为62例、27例、23例,观察彩色多普勒超声的影像学特征,分析静脉内径与病程的相关性,并分析超声诊断分级与临床症状积分、体质量指数(BMI)、妊娠次数、既往工作站立时间的相关性。结果:不同超声诊断分级患者的静脉内径、静脉丛范围和静脉流速差异具有统计学意义(P<0.05)。静脉内径与病程呈正相关(P<0.05),超声诊断分级与临床症状积分、妊娠次数、既往工作站立时间呈显著正相关(P<0.05),与BMI呈负相关(P<0.05)。结论:彩色多普勒超声对盆腔瘀血综合征具有特异性的诊断价值,超声诊断分级、静脉内径与临床因素存在一定的的关联性。  相似文献   
165.
Li  Zhengtu  Li  Yinhu  Sun  Ruilin  Li  Shaoqiang  Chen  Lingdan  Zhan  Yangqing  Xie  Mingzhou  Yang  Jiasheng  Wang  Yanqun  Zhu  Airu  Gu  Guoping  Yu  Le  Li  Shuaicheng  Liu  Tingting  Chen  Zhaoming  Jian  Wenhua  Jiang  Qian  Su  Xiaofen  Gu  Weili  Chen  Liyan  Cheng  Jing  Zhao  Jincun  Lu  Wenju  Zheng  Jinping  Li  Shiyue  Zhong  Nanshan  Ye  Feng 《中国科学:生命科学英文版》2021,64(12):2129-2143
Science China Life Sciences - Prolonged viral RNA shedding and recurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in coronavirus disease 2019 (COVID-19) patients have been...  相似文献   
166.
Advances in high-throughput sequencing(HTS)have fostered rapid developments in the field of microbiome research,and massive microbiome datasets are now being generated.However,the diversity of software tools and the complexity of analysis pipelines make it difficult to access this field.Here,we systematically summarize the advantages and limitations of micro-biome methods.Then,we recommend specific pipelines for amplicon and metagenomic analyses,and describe commonly-used software and databases,to help researchers select the appropriate tools.Furthermore,we introduce statistical and visualization methods suit-able for microbiome analysis,including alpha-and beta-diversity,taxonomic composition,difference compar-isons,correlation,networks,machine learning,evolu-tion,source tracing,and common visualization styles to help researchers make informed choices.Finally,a step-by-step reproducible analysis guide is introduced.We hope this review will allow researchers to carry out data analysis more effectively and to quickly select the appropriate tools in order to efficiently mine the bio-logical significance behind the data.  相似文献   
167.
Dear Editor, A series of studies had focused on the ecological stability of human microbiome (Lozupone et al.,2012;Faith et al.,2013;Moya and Ferrer,2016).Despite the continuous perturbation and the highly personalized composition within the human microbiome (Human Microbiome Project,2012),healthy adults stably maintain their microbial communities in terms of space and time (Faith et al.,2013;Moya and Ferrer,2016;Oh et al.,2016).This stability is proved to be critical for the well-being of human body (Lozupone et al.,2012).On the contrary,major shifts in microbial community composition are often related to diseases (Lynch and Pedersen,2016).  相似文献   
168.
Liao  Jingqiu  Cai  Yan  Wang  Xinrui  Shang  Chenxu  Zhang  Qian  Shi  Huizhong  Wang  Shifeng  Zhang  Dongdong  Zhou  Yongcan 《Probiotics and antimicrobial proteins》2021,13(4):1119-1137
Probiotics and Antimicrobial Proteins - A potential host-derived probiotic, Bacillus subtilis 6-3-1, was successfully screened from 768 isolates from the intestines of healthy hybrid grouper...  相似文献   
169.
Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions.  相似文献   
170.
Posttranslational modifications, such as SUMOylation, play specific roles in the life cycle of invading pathogens. However, the effect of SUMOylation on the adaptation, pathogenesis, and transmission of influenza A virus (IAV) remains largely unknown. Here, we found that a conserved lysine residue at position 612 (K612) of the polymerase basic protein 1 (PB1) of IAV is a bona fide SUMOylation site. SUMOylation of PB1 at K612 had no effect on the stability or cellular localization of PB1, but was critical for viral ribonucleoprotein (vRNP) complex activity and virus replication in vitro. When tested in vivo, we found that the virulence of SUMOylation-defective PB1/K612R mutant IAVs was highly attenuated in mice. Moreover, the airborne transmission of a 2009 pandemic H1N1 PB1/K612R mutant virus was impaired in ferrets, resulting in reversion to wild-type PB1 K612. Mechanistically, SUMOylation at K612 was essential for PB1 to act as the enzymatic core of the viral polymerase by preserving its ability to bind viral RNA. Our study reveals an essential role for PB1 K612 SUMOylation in the pathogenesis and transmission of IAVs, which can be targeted for the design of anti-influenza therapies.  相似文献   
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