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941.
Lei Liu Wanbing Liu Yan Liu Guomei Kou Yaqiong Zheng Liping Cai Shengdian Wang Shangen Zheng 《Blood and Genomics》2021,26(1):41-47
This paper aimed to analyze antibody responses to SARS-CoV-2 in various populations. Two hundred and six COVID-19 patients, 46 convalescent patients, and 270 healthy population were enrolled. Antibodies against nucleocapsid protein (N) and spike protein's receptor-binding domain (RBD), and neutralizing antibody were detected. The results demonstrated both anti-N and anti-RBD antibodies could be detected in about 80% of COVID-19 patients and 90% of convalescent patients, while no antibodies could be detected in some convalescents and patients even after 14 days post-onset of symptoms. The level of anti-RBD antibody strongly correlated with the neutralizing activity of sera from these two cohorts. The titer of neutralizing antibody was lower in convalescents than that in active COVID-19 patients. In addition, the titer of neutralizing antibody was less than 1:80 in none of the severe COVID-19 patients, 18.8% in non-severe COVID-19 patients, and 32.6% in convalescents. The study suggests that the level of anti-RBD antibody is closely related to neutralization activity in COVID-19 patients and convalescents. Some SARS-CoV-2-infected cases trigger a weak antiviral immune response, and the level of neutralizing antibody may have a faster decay rate. 相似文献
942.
Zheng Zhou Jiajun Wu Wenli Ma Feilin Dong Jiafeng Wang 《Journal of cellular and molecular medicine》2023,27(2):204
Necroptosis is a unique programmed death mechanism of necrotic cells. However, its role and specific mechanism in cancer remain unclear, and a systematic pan‐cancer analysis of necroptosis is yet to be conducted. Thus, we performed a specific pan‐cancer analysis using The Cancer Genome Atlas and Genotype‐Tissue Expression databases to analyse necroptosis expression in terms of cancer prognosis, DNA methylation status, tumour mutative burden, microsatellite instability, immune cell infiltration in different types of cancer and molecular mechanisms. For the first time, we explored the correlation between necroptosis and immunotherapy prognosis. Thus, our study provides a relatively comprehensive understanding of the carcinogenicity of necroptosis in different types of cancer. It is suggested that necroptosis can be used to evaluate the sensitivity of different patients to immunotherapy and may become a potential target for tumour immunotherapy. 相似文献
943.
Pan Y Chu T Dong S Hao Y Ren X Wang J Wang W Li C Zhang Z Zhou Y 《Molecular biology reports》2012,39(9):8581-8594
The study was designed to investigate feasibility of tissue culture in vitro utilizing static culture method. Annulus fibrosus cells obtained from spine of rabbits were cultured. Results showed that fibrous tissue infiltration could be detected in shallow layer. With extended time, tissue infiltration depth increased, but there were still a large amount of holes in central part. Fibrous tissue infiltration was detected in the control side products and inner infiltration wasn't obvious. Hydroxyproline content of the control side products gradually increased with extended culture time. Hydroxyproline content of the control side products in the third and fourth month was significantly higher than that in the first month, but lower than those of the experimental side products and normal annulus fibrosus cells. DNA content of the control side products in the third and fourth month was significantly increased compared to the first month. DNA content of the control side products at each phase point was significantly lower than that of the experimental side and normal annulus fibrosus cells. Furthermore, there was lower expression levels of the type I, II collagen mRNA and protein in the experimental side scaffolds compared to the control side product. This study demonstrates the successful formation of Intervertebral disc Anulus Fibrosus in vitro by static culture method. 相似文献
944.
Ying Wang Yunjing Zhang Xinwan Su Qiongzi Qiu Yuan Yuan Chunhua Weng Sailan Zou Yan Tian Weidong Han Pengyuan Liu Xingyi Guo Jianhua Mao Xianghui Fu Ping Wang Weiqiang Lin 《International journal of biological sciences》2022,18(4):1491
Clear cell renal cell carcinoma (ccRCC) is a primary kidney cancer with high aggressive phenotype and extremely poor prognosis. Accumulating evidence suggests that circular RNAs (circRNAs) play pivotal roles in the occurrence and development of various human cancers. However, the expression, clinical significance and regulatory role of circRNAs in ccRCC remain largely unclear. Here we report that circDVL1 to be reduced in the serums and tissues from ccRCC patients, and to negatively correlate with ccRCC malignant features. Overexpression of circDVL1 inhibits proliferation, induces G1/S arrest, triggers apoptosis, and reduces migration and invasion in different ccRCC cells in vitro. Correspondingly, circDVL1 overexpression suppresses ccRCC tumorigenicity in a mouse xenograft model. Mechanistically, circDVL1 serves as a sponge for oncogenic miR-412-3p, thereby preventing miR-412-3p-mediated repression of its target protocadherin 7 (PCDH7) in ccRCC cells. Collectively, our results demonstrate that circDVL1 exerts tumor-suppressive function during ccRCC progression through circDVL1/miR-412-3p/PCDH7 axis, and suggest that circDVL1 could be a novel diagnostic and prognositc marker and therapeutic target for ccRCC. 相似文献
945.
In this paper, the global robust stability problem of delayed Takagi–Sugeno fuzzy Hopfield neural networks with discontinuous
activation functions (TSFHNNs) is considered. Based on Lyapunov stability theory and M-matrices theory, we derive a stability criterion to guarantee the global robust stability of TSFHNNs. Compared with the existing
literature, we remove the assumptions on the neuron activations such as Lipschitz conditions, bounded, monotonic increasing
property or the assumption that the right-limit value is bigger than the left one at the discontinuous point. Finally, two
numerical examples are given to show the effectiveness of the proposed stability results. 相似文献
946.
Additives are known to improve the performance of organic photovoltaic devices based on mixtures of a low bandgap polymer, poly[2,6‐(4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b′]‐dithiophene)‐alt‐4,7‐(2,1,3‐benzothiadiazole)] (PCPDTBT) and [6,6]‐phenyl C61‐butyric acid methyl ester (PCBM). The evolution of the morphology during the evaporation of the mixed solvent, which comprises additive and chlorobenzene (CB), is investigated by in‐situ grazing incidence X‐ray scattering, providing insight into the key role the additive plays in developing a multi‐length‐scale morphology. Provided the additive has a higher vapor pressure and a selective solubility for PCBM, as the host solvent (CB) evaporates, the mixture of the primary solvent and additive becomes less favorable for the PCPDTBT, while completely solubilizing the PCBM. During this process, the PCPDTBT first crystallizes into fibrils and then the PCBM, along with the remaining PCPDTBT, is deposited, forming a phase‐separated morphology comprising domains of pure, crystalline PCPDTBT fibrils and another domain that is a PCBM‐rich mixture with amorphous PCPDTBT. X‐ray/neutron scattering and diffraction methods, in combination with UV–vis absorption spectroscopy and transmission electron microscopy, are used to determine the crystallinity and phase separation of the resultant PCPDTBT/PCBM thin films processed with or without additives. Additional thermal annealing is carried out and found to change the packing of the PCPDTBT. The two factors, degree of crystallinity and degree of phase separation, control the multi‐length‐scale morphology of the thin films and significantly influence device performance. 相似文献
947.
948.
949.
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
950.
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