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991.
核不均一核糖核蛋白R(hnRNPR)是一种与mRNA生物学功能密切相关的RNA结合蛋白质,与多种肿瘤细胞的恶性转化相关。然而,在非小细胞肺癌(NSCLC)中的作用机制尚不清楚。本研究通过检索公共数据库发现,hnRNPR蛋白主要在肺癌细胞核中表达,hnRNPR mRNA在非小细胞肺癌组织中高表达,并且与肺腺癌患者的生存率呈负相关;hnRNPR的表达与非小细胞肺癌患者的性别、T分期显著相关(P<0.05)。构建hnRNPR基因沉默的非小细胞肺癌稳定细胞株,检测细胞功能变化,结果显示,hnRNPR基因沉默抑制了细胞增殖、迁移和侵袭能力以及上皮-间质转化(EMT),并将细胞周期阻滞在G1期(P<0.01)。生物信息学分析显示,非小细胞肺癌中hnRNPR基因与9 310个基因的表达正相关(皮尔逊相关系数>0,P<0.05),与10 680个基因的表达负相关(皮尔逊相关系数<0,P<0.05)。综上所述,hnRNPR在非小细胞肺癌中高表达,可能作为剪接体的组分,通过调节相关基因的表达,促进了NSCLC细胞的恶性转化。 相似文献
992.
Yuan Bo Wu Wei Yue Shengjuan Zou Penghui Yang Ruoting Zhou Xiaode 《International microbiology》2022,25(3):571-586
International Microbiology - The photovoltaic power station in Qinghai has been built for 8 years; however, its impact on the regional soil ecological environment has not been studied in... 相似文献
993.
Yuanzhi Chen Chenguang Shen Jing Chen Junyu Chen Fentian Chen Limin Zhang Xue Liu Siyuan Chen Sen Xue Yongliang Liu Jixian Tang Quan Yuan Yixin Chen Wenxin Luo Ningshao Xia 《中国病毒学》2022,37(4):619-622
Highlights
1. Class-switch recombination was mimicked in hybridomas through a controllable expression system of activation-induced cytidine deaminase.
2. IgG antibodies were generated through this system in an anti-Flu B IgM hybridoma 7G1.
3. IgG1 and IgG2a subtypes of 7G1 present improved antiviral activity in vitro and in vivo. 相似文献
1. Class-switch recombination was mimicked in hybridomas through a controllable expression system of activation-induced cytidine deaminase.
2. IgG antibodies were generated through this system in an anti-Flu B IgM hybridoma 7G1.
3. IgG1 and IgG2a subtypes of 7G1 present improved antiviral activity in vitro and in vivo. 相似文献
994.
Hang Yang Huijun Yuan Xiaohui Zhao Meng Xun Shangrui Guo Nan Wang Bing Liu Hongliang Wang 《中国病毒学》2022,37(3):380-389
The recent COVID-19 pandemic poses a global health emergency. Cellular entry of the causative agent SARS-CoV-2 is mediated by its spike protein interacting with cellular receptor-human angiotensin converting enzyme 2 (ACE2). Here, by using lentivirus based pseudotypes bearing spike protein, we demonstrated that entry of SARS-CoV-2 into host cells was dependent on clathrin-mediated endocytosis, and phosphoinositides played essential roles during this process. In addition, we showed that the intracellular domain and the catalytic activity of ACE2 were not required for efficient virus entry. Finally, we showed that the current predominant Delta variant, although with high infectivity and high syncytium formation, also entered cells through clathrin-mediated endocytosis. These results provide new insights into SARS-CoV-2 cellular entry and present proof of principle that targeting viral entry could be an effective way to treat different variant infections. 相似文献
995.
Yuan Zhang Chunjie Li Xianliang Ke Dan Luo Yan Liu Quanjiao Chen Hanzhong Wang Xiaohui Song Zhenhua Zheng 《中国病毒学》2022,37(3):459-461
Highlights:
The biosensor reported in our study can monitor SARS-CoV-2 Mpro activity in living cells instead of in vitro solutions.
The biosensor reported in our study is sensitive and easy to operate.
It is suitable for high-throughput screening.
It has the potential to be used in small animal models. 相似文献
The biosensor reported in our study can monitor SARS-CoV-2 Mpro activity in living cells instead of in vitro solutions.
The biosensor reported in our study is sensitive and easy to operate.
It is suitable for high-throughput screening.
It has the potential to be used in small animal models. 相似文献
996.
Lei Yang Lingqian Tian Leshan Li Qiuhong Liu Xiang Guo Yuan Zhou Rongjuan Pei Xinwen Chen Yun Wang 《中国病毒学》2022,37(3):341-347
Transformation-associated recombination (TAR) has been widely used to assemble large DNA constructs. One of the significant obstacles hindering assembly efficiency is the presence of error-prone DNA repair pathways in yeast, which results in vector backbone recircularization or illegitimate recombination products. To increase TAR assembly efficiency, we prepared a dual-selective TAR vector, pGFCS, by adding a PADH1-URA3 cassette to a previously described yeast-bacteria shuttle vector, pGF, harboring a PHIS3-HIS3 cassette as a positive selection marker. This new cassette works as a negative selection marker to ensure that yeast harboring a recircularized vector cannot propagate in the presence of 5-fluoroorotic acid. To prevent pGFCS bearing ura3 from recombining with endogenous ura3-52 in the yeast genome, a highly transformable Saccharomyces cerevisiae strain, VL6-48B, was prepared by chromosomal substitution of ura3-52 with a transgene conferring resistance to blasticidin. A 55-kb genomic fragment of monkeypox virus encompassing primary detection targets for quantitative PCR was assembled by TAR using pGFCS in VL6-48B. The pGFCS-mediated TAR assembly showed a zero rate of vector recircularization and an average correct assembly yield of 79% indicating that the dual-selection strategy provides an efficient approach to optimizing TAR assembly. 相似文献
997.
998.
Yuqi Zhu Xinyi Yang Jingna Xun Jun Liu Qing Wen Yixiao Lin Xiaoting Shen Jun Chen Songhua Yuan Xiaying Zhao Jing Wang Hanyu Pan Jinlong Yang Zhiming Liang Yue Liang Qinru Lin Huitong Liang Min Li Jianping Liu Yinzhong Shen Xiaoyan Zhang Pengfei Wang Daru Lu Chunhua Yin Jianqing Xu Shibo Jiang Hongzhou Lu Huanzhang Zhu 《中国病毒学》2022,37(6):831-841
The prevalence of SARS-CoV-2 variants of concern (VOCs) is still escalating throughout the world. However, the level of neutralization of the inactivated viral vaccine recipients’ sera and convalescent sera against all VOCs, including B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.617.2 (Delta), and B.1.1.529 (Omicron) remains to be lack of comparative analysis. Therefore, we constructed pseudoviruses of five VOCs using a lentiviral-based system and analyzed their viral infectivity and neutralization resistance to convalescent and BBIBP-CorV vaccinee serum at different times. Our results show that, compared with the wild-type strain (WT), five VOC pseudoviruses showed higher infection, of which B.1.617.2 and B.1.1.529 variant pseudoviruses exhibited higher infection rates than wild-type or other VOC strains, respectively. Sera from 10 vaccinated individuals at the 1, 3 and 5-month post second dose or from 10 convalescent at 14 and 200 days after discharge retained neutralizing activity against all strains but exhibited decreased neutralization activity significantly against the five VOC variant pseudoviruses over time compared to WT. Notably, 100% (30/30) of the vaccinee serum samples showed more than a 2.5-fold reduction in neutralizing activity against B.1.1.529, and 90% (18/20) of the convalescent serum samples showed more than 2.5-fold reduction in neutralization against B.1.1.529. These findings demonstrate the reduced protection against the VOCs in vaccinated and convalescent individuals over time, indicating that it is necessary to have a booster shot and develop new vaccines capable of eliciting broad neutralization antibodies. 相似文献
999.
Ge Gao Xue Hu Yiwu Zhou Juhong Rao Xiaoyu Zhang Yun Peng Jiaxuan Zhao Yanfeng Yao Kunpeng Liu Mengying Liang Hang Liu Fei Deng Han Xia Chao Shan Zhiming Yuan 《中国病毒学》2022,37(2):299-302
Highlights
1. Delta variant of SARS-CoV-2 can effectively infect the Rhesus macaque.
2. The Delta variant grows faster than the early strain isolated from Wuhan in late 2019.
3. The shedding pattern, viral load and disease severity of Delta variant are similar with the early strain isolated from Wuhan in late 2019.
4. This study supports the attributed rapid disease spread of the Delta variant. 相似文献
1. Delta variant of SARS-CoV-2 can effectively infect the Rhesus macaque.
2. The Delta variant grows faster than the early strain isolated from Wuhan in late 2019.
3. The shedding pattern, viral load and disease severity of Delta variant are similar with the early strain isolated from Wuhan in late 2019.
4. This study supports the attributed rapid disease spread of the Delta variant. 相似文献
1000.
草地贪夜蛾Spodoptera frugiperda(J. E. Smith)入侵我国多个地区,逐渐形成地理种群。在草地贪夜蛾核型多角体病毒Spodoptera frugiperda multiple nucleopolyhedrovirus(SfMNPV)生物农药的生产过程中发现,不同地理来源的宿主对SfMNPV的敏感性和产量存在明显差异,显著影响了SfMNPV的生产效率。为解析其敏感性差异及其产生的原因,本研究首先对云南德宏、广东广州、广西钦州、西藏林芝4个地区草地贪夜蛾种群基因型进行了鉴定,采用生物测定法测试SfMNPV对4龄幼虫的口服毒力,然后,通过向幼虫体内注射草地贪夜蛾核多角体病毒出芽型病毒粒子(budded virions,BVs)的方式,越过口服感染中肠的过程,分析敏感性差异发生的阶段。最后比较了高敏感和低敏感种群中肠肠液pH,并基于16S rDNA测序测定了肠道菌群组成。结果表明,广西种群属于纯合玉米型,其余种群为带有水稻型COI标记的杂合玉米型。广西种群对SfMNPV的口服敏感性最低,西藏种群的敏感性最高,但两者注射BV后死亡率差异无统计学意义,暗示病毒敏感性差异发生在口服感染阶段。广西种群中肠pH略低于西藏种群,并且较于西藏种群,广西种群相肠道乳杆菌Lactobacillus丰度高。本文结果表明,肠道微环境的差异可能是不同地理种群草地贪夜蛾对SfMNPV口服敏感性产生差异的原因。 相似文献