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121.
YB1 is a negative regulator in liver fibrosis. We wondered whether SJYB1, a homologous protein of YB1 from Schistosoma japonicum, has an effect on liver fibrosis in vitro. Recombinant SJYB1 (rSJYB1) protein was expressed in a bacterial system and purified by Ni‐NTA His·Bind Resin. A human hepatic stellate cell line, the LX‐2 cell line, was cultured and treated with rSJYB1. The role of rSJYB1 on LX‐2 cells was then analysed by Western blot and luciferase assay. We succeeded in expressing and purifying SJYB1 in a bacterial system and the purified rSJYB1 could be recognized by S japonicum‐infected rabbit sera. Western bolt analysis showed that rSJYB1 inhibited the expression of collagen type I, but had little effect on α‐smooth muscle actin (α‐SMA). Further analysis revealed that rSJYB1 inhibited the activity of collagen α1 (I) (COL1A1) promoter and functioned at ?1592/?1176 region of COL1A1 promoter. Our data demonstrate that rSJYB1‐mediated anti‐fibrotic activity involves inhibiting the activity of COL1A1 promoter and subsequently suppressing the expression of collagen type I in hepatic stellate cells.  相似文献   
122.
Vascular progenitor cells (VPCs) present in the adventitia of the vessel wall play a critical role in the regulation of vascular repair following injury. This study aimed to assess the function of VPCs isolated from patients with Marfan syndrome (MFS). VPCs were isolated from control and MFS donors and characterized. Compared with control‐VPCs, MFS‐VPCs exhibited cellular senescence as demonstrated by increased cell size, higher SA‐β‐gal activity and elevated levels of p53 and p21. RNA sequencing showed that several cellular process‐related pathways including cell cycle and cellular senescence were significantly enriched in MFP‐VPCs. Notably, the expression level of TGF‐β1 was much higher in MFS‐VPCs than control‐VPCs. Treatment of control‐VPCs with TGF‐β1 significantly enhanced mitochondrial reactive oxidative species (ROS) and induced cellular senescence whereas inhibition of ROS reversed these effects. MFS‐VPCs displayed increased mitochondrial fusion and decreased mitochondrial fission. Treatment of control‐VPCs with TGF‐β1 increased mitochondrial fusion and reduced mitochondrial fission. Nonetheless, treatment of mitofusin2 (Mfn2)‐siRNA inhibited TGF‐β1‐induced mitochondrial fusion and cellular senescence. Furthermore, TGF‐β1‐induced mitochondrial fusion was mediated by the AMPK signalling pathway. Our study shows that TGF‐β1 induces VPC senescence in patients with MFS by mediating mitochondrial dynamics via the AMPK signalling pathway.  相似文献   
123.
目的:探讨表皮生长因子受体(EGFR)基因突变与棘皮动物微管相关样蛋白4与间变性淋巴瘤激酶(EML4-ALK)融合基因共存(以下简称双基因异常)的非小细胞肺癌的临床病理特征及治疗策略。方法:回顾性收集并分析2012年1月至2016年12月我院收治的EGFR突变与EML4-ALK融合基因共存的非小细胞肺癌患者的临床资料及病理特点。结果:11例双突变非小细胞肺癌占医院同期入院非小细胞肺癌患者的0.68%(11/1620);男性6例,女性5例;年龄23-70岁,平均年龄51.6岁;11例患者均不吸烟;腺癌9例,肉瘤样癌2例;临床分期,ⅠA期3例,ⅡB期1例,ⅢA期1例,ⅢB期1例,ⅠV期5例;6例行手术治疗,4例使用传统化疗,最好疗效为稳定(SD),最长无进展生存期(PFS)为6月;5例患者使用表皮生长因子酪氨酸激酶抑制剂(EGFR-TKⅠ)治疗,使用EGFR-TKⅠ最好疗效为部分缓解(PR),PFS为3-23月,中位PFS为9月;截止2017年12月,死亡4例,11例患者的生存时间为1-67月,中位存活时间为21月。结论:EGFR基因突变与EML4-ALK融合基因共存型非小细胞肺癌临床少见,多见于不吸烟或少吸烟的肺腺癌患者,双基因异常的非小细胞肺癌的靶向药物的治疗缺乏统一性,有待进一步研究,基于EGFR及EML4-ALK的磷酸化水平或肿瘤突变负荷选择靶向药物的个体化精准治疗是非常重要的。  相似文献   
124.
Liu  Xi  Ding  Li  Yuan  Jing  Liao  Jian  Duan  Lian  Wang  Wenfei  Tan  Weiguo  Yu  Weiye  Zhou  Boping  Chen  Xinchun  Yang  Zheng 《中国病毒学》2019,34(3):334-337
<正>Dear Editor,H7 N9 is a recently identified subtype of influenza A virus that caused a major outbreak in humans in China in 2013.According to the latest data provided by the Chinese Center for Disease Control and Prevention(http://www.moh.gov.cn/zwgk/yqbb3/ejlist.shtml, updated on October 31, 2018),the mortality rate of H7 N9 infections in China amounts to  相似文献   
125.
Members of the Chenopodiaceae are the most dominant elements in the central Asian desert. The different genera and species within this family are common in desert vegetation types. Should it prove possible to link pollen types in this family to specific desert vegetation, it would be feasible to trace vegetation successions in the geological past. Nevertheless, the morphological similarity of pollen grains in the Chenopodiaceae rarely permits identification at the generic level. Although some pollen classifications of Chenopodiaceae have been proposed, none of them tried to link pollen types to specific desert vegetation types in order to explore their ecological significance. Based on the pollen morphological characters of 13 genera and 24 species within the Chenopodiaceae of eastern central Asia, we provide a new pollen classification of this family with six pollen types and link them to those plant communities dominated by Chenopodiaceae, for example, temperate dwarf semi‐arboreal desert (Haloxylon type), temperate succulent halophytic dwarf semi‐shrubby desert (Suaeda, Kalidium, and Atriplex types), temperate annual graminoid desert (Kalidium type), temperate semi‐shrubby and dwarf semi‐shrubby desert (Kalidium, Iljini, and Haloxylon types), and alpine cushion dwarf semi‐shrubby desert (Krascheninnikovia type). These findings represent a new approach for detecting specific desert vegetation types and deciphering ecosystem evolution in eastern central Asia.  相似文献   
126.
127.
Zygotic genome activation (ZGA) is one of the most critical events at the beginning of mammalian preimplantation embryo development (PED). The mechanisms underlying mouse ZGA remain unclear although it has been widely studied. In the present study, we identified that tricho-rhino-phalangeal syndrome 1 (TRPS1), an atypical GATA family member, is an important factor for ZGA in mouse PED. We found that the Trps1 mRNA level peaked at the one-cell stage while TRPS1 protein did so at the two/four-cell stage. Knockdown of Trps1 by the microinjection of Trps1 siRNA reduced the developmental rate of mouse preimplantation embryos by approximately 30%, and increased the expression of ZGA marker genes MuERV-L and Zscan4d via suppressing the expression of major histone markers H3K4me3 and H3K27me3. Furthermore, Trps1 knockdown decreased the expression of Sox2 but increased Oct4 expression. We conclude that TRPS1 may be indispensable for zygotic genome activation during mouse PED.  相似文献   
128.
Senescence is a tumor suppressor program characterized by a stable growth arrest while maintaining cell viability. Senescence-associated ribogenesis defects (SARD) have been shown to regulate senescence through the ability of the ribosomal protein S14 (RPS14 or uS11) to bind and inhibit the cyclin-dependent kinase 4 (CDK4). Here we report another ribosomal protein that binds and inhibits CDK4 in senescent cells: L22 (RPL22 or eL22). Enforcing the expression of RPL22/eL22 is sufficient to induce an RB and p53-dependent cellular senescent phenotype in human fibroblasts. Mechanistically, RPL22/eL22 can interact with and inhibit CDK4-Cyclin D1 to decrease RB phosphorylation both in vitro and in cells. Briefly, we show that ribosome-free RPL22/eL22 causes a cell cycle arrest which could be relevant during situations of nucleolar stress such as cellular senescence or the response to cancer chemotherapy.  相似文献   
129.
130.
Soybean cyst nematode (SCN, Heterodera glycines) is a major pest of soybean that is spreading across major soybean production regions worldwide. Increased SCN virulence has recently been observed in both the United States and China. However, no study has reported a genome assembly for H. glycines at the chromosome scale. Herein, the first chromosome‐level reference genome of X12, an unusual SCN race with high infection ability, is presented. Using whole‐genome shotgun (WGS) sequencing, Pacific Biosciences (PacBio) sequencing, Illumina paired‐end sequencing, 10X Genomics linked reads and high‐throughput chromatin conformation capture (Hi‐C) genome scaffolding techniques, a 141.01‐megabase (Mb) assembled genome was obtained with scaffold and contig N50 sizes of 16.27 Mb and 330.54 kilobases (kb), respectively. The assembly showed high integrity and quality, with over 90% of Illumina reads mapped to the genome. The assembly quality was evaluated using Core Eukaryotic Genes Mapping Approach and Benchmarking Universal Single‐Copy Orthologs. A total of 11,882 genes were predicted using de novo, homolog and RNAseq data generated from eggs, second‐stage juveniles (J2), third‐stage juveniles (J3) and fourth‐stage juveniles (J4) of X12, and 79.0% of homologous sequences were annotated in the genome. These high‐quality X12 genome data will provide valuable resources for research in a broad range of areas, including fundamental nematode biology, SCN–plant interactions and co‐evolution, and also contribute to the development of technology for overall SCN management.  相似文献   
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