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61.
62.
Ruilong Zhang Zhiping Zhou Yi Wang Xiaohui Dai Li Chen Jiangdong Dai 《仿生工程学报(英文版)》2021,18(3):559-573
Mimicry of nature drives the development of bionic materials.Bionic superhydrophobic materials are a kind of high-efficiency materials to handle oil spills and ... 相似文献
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Miao L Dai Y Zhang J 《American journal of physiology. Heart and circulatory physiology》2002,283(3):H983-H989
This study was undertaken to demonstrate the role of the RhoA/Rho kinase pathway in endothelin-1 (ET-1)-induced contraction of the rabbit basilar artery. Isometric tension and Western blot were used to examine ET-1-induced contraction and RhoA activation. The upstream effect on ET-1-induced RhoA activity was determined by using ET(A) and ET(B) receptor antagonists, protein kinase C (PKC), tyrosine kinase, and phosphatidylinositol-3 kinase inhibitors. The downstream effect of ET-1-induced contraction and RhoA activity was studied in the presence of the Rho kinase inhibitor Y-27632. The effect of Rho kinase inhibitor on ET-1-induced myosin light chain (MLC) phosphorylation was investigated by using urea-glycerol-PAGE immunoblotting. We found 1) ET-1 increased RhoA activity (membrane binding RhoA) in a concentration-dependent manner; 2) ET(A), but not ET(B), receptor antagonist abolished the effect of ET-1 on RhoA activation; 3) phosphodylinositol-3 kinase inhibitor, but not PKC and tyrosine kinase inhibitors, reduced ET-1-induced RhoA activation; 4) Rho kinase inhibitor Y-27632 (10 microM) inhibited ET-1-induced contraction; and 5) ET-1 increased the level of MLC phosphorylation. Rho kinase inhibitor Y-27632 reduced the effect of ET-1 on MLC phosphorylation. This study demonstrated that RhoA/Rho kinase activation is involved in ET-1-induced contraction in the rabbit basilar artery. Phosphodylinositol-3 kinase and MLC might be the upstream and downstream factors of RhoA activation. 相似文献
65.
Yimin Dai Qingfeng Zhou Chengwen Zhang Yanhua Song Xiaoyan Tian Xiangbin Zhang Chunyi Xue Shun Xu Yingzuo Bi Yongchang Cao 《Journal of virology》2012,86(22):12456
Porcine orthoreoviruses belong to the family Reoviridae and cause mainly mild enteritis in piglets. We present here the complete genome sequence of a novel porcine orthoreovirus strain (GD-1) isolated from a piglet in southern China. Our data will facilitate future investigations of the molecular characteristics and epidemiology of porcine orthoreoviruses. 相似文献
66.
Jiaomeng Pan Zhen Xiang Qingqiang Dai Zhenqiang Wang Bingya Liu Chen Li 《Journal of cellular biochemistry》2019,120(8):13478-13486
Lack of guidelines for personalized chemotherapy treatment after surgery has caused gastric cancer (GC) patients' unnecessary exposure to toxicity and the financial burden of chemotherapy treatments. In our study, we aimed to identify potential biomarkers to predict GC patients' susceptibility to platinum-based on Gene Expression Omnibus (GEO) data sets. A total of 603 differentially expressed genes (DEGs) were identified between platinum-resistant cell lines and platinum-sensitive cell lines based on the Cancer Cell Line Encyclopedia (CCLE) data sets. A total of 253 patients who had accepted radical gastrectomy were recruited, of which 97 received platinum-based chemotherapy and 156 were untreated. Three biomarkers (BRMS1, ND6, SRXN1) were then selected by univariate and multivariate Cox regression analysis to establish the predictive models using nomogram. Then this model was further validated through the GEO data set (GSE62254) which showed that this model could precisely predict the disease-free survival and overall survival of patients treated with platinum-based chemotherapy after surgery compared with untreated GC patients (P < 0.0001). This predictive model might provide helpful messages about the patients' susceptibility to platinum to guide personalized chemotherapy. 相似文献
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Under the treatment of 0.5—2.0 μA direct electric currents, the number of cell clusters derived from wheat (Triticum aestivum L. ) protoplasts was dramatically increased. The effect was related to the time-length of the treatments, and appeared only when the timelength was more than the threshold. The threshold time decreased with increase of electric current intensity. The effect was not related to the starting time of the treatments in culture of the protoplasts. 相似文献
68.
Langerhans cells (LCs) are antigen-presenting cells in the skin that play sentinel roles in host immune defense by secreting proinflammatory molecules and activating T cells. Here we studied the interaction of vaccinia virus with XS52 cells, a murine epidermis-derived dendritic cell line that serves as a surrogate model for LCs. We found that vaccinia virus productively infects XS52 cells, yet this infection displays an atypical response to anti-poxvirus agents. Whereas adenosine N1-oxide blocked virus production and viral protein synthesis during a synchronous infection, cytosine arabinoside had no effect at concentrations sufficient to prevent virus replication in BSC40 monkey kidney cells. Vaccinia virus infection of XS52 cells not only failed to elicit the production of various cytokines, including tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, IL-10, IL-12 p40, alpha interferon (IFN-alpha), and IFN-gamma, it actively inhibited the production of proinflammatory cytokines TNF-alpha and IL-6 by XS52 cells in response to exogenous lipopolysaccharide (LPS) or poly(I:C). Infection with a vaccinia virus mutant lacking the E3L gene resulted in TNF-alpha secretion in the absence of applied stimuli. Infection of XS52 cells or BSC40 cells with the DeltaE3L virus, but not wild-type vaccinia virus, triggered proteolytic decay of IkappaBalpha. These results suggest a novel role for the E3L protein as an antagonist of the NF-kappaB signaling pathway. DeltaE3L-infected XS52 cells secreted higher levels of TNF-alpha and IL-6 in response to LPS and poly(I:C) than did cells infected with the wild-type virus. XS52 cells were productively infected by a vaccinia virus mutant lacking the K1L gene. DeltaK1L-infected cells secreted higher levels of TNF-alpha and IL-6 in response to LPS than wild-type virus-infected cells. Vaccinia virus infection of primary LCs harvested from mouse epidermis was nonpermissive, although a viral reporter protein was expressed in the infected LCs. Vaccinia virus infection of primary LCs strongly inhibited their capacity for antigen-specific activation of T cells. Our results highlight suppression of the skin immune response as a feature of orthopoxvirus infection. 相似文献
69.
Ca(2+) binding to synaptotagmin 1 triggers fast exocytosis of synaptic vesicles that have been primed for release by SNARE-complex assembly. Besides synaptotagmin 1, fast Ca(2+)-triggered exocytosis requires complexins. Synaptotagmin 1 and complexins both bind to assembled SNARE complexes, but it is unclear how their functions are coupled. Here we propose that complexin binding activates SNARE complexes into a metastable state and that Ca(2+) binding to synaptotagmin 1 triggers fast exocytosis by displacing complexin from metastable SNARE complexes. Specifically, we demonstrate that, biochemically, synaptotagmin 1 competes with complexin for SNARE-complex binding, thereby dislodging complexin from SNARE complexes in a Ca(2+)-dependent manner. Physiologically, increasing the local concentration of complexin selectively impairs fast Ca(2+)-triggered exocytosis but retains other forms of SNARE-dependent fusion. The hypothesis that Ca(2+)-induced displacement of complexins from SNARE complexes triggers fast exocytosis accounts for the loss-of-function and gain-of-function phenotypes of complexins and provides a molecular explanation for the high speed and synchronicity of fast Ca(2+)-triggered neurotransmitter release. 相似文献
70.
Quantifying ecosystem service trade‐offs for plantation forest management to benefit provisioning and regulating services 下载免费PDF全文
There is increasing interest worldwide regarding managing plantation forests in a manner that maintains or improves timber production, enhances ecosystem services, and promotes long‐term sustainability of forest resources. We selected the Gan River Basin, the largest catchment of Poyang Lake and a region with a typical plantation distribution in South China, as the study region. We evaluated and mapped four important forest ecosystem services, including wood volume, carbon storage, water yield, and soil retention at a 30 × 30 m resolution, then quantified their trade‐offs and synergies at the county and subwatershed scales. We found that the wood volume and carbon storage services, as well as the soil retention and water yield, exhibited synergistic relationships. However, the carbon storage displayed a trade‐off relationship with the water yield. Additionally, we compared the beneficial spatial characteristics among dominant species in the study region. The results showed that the Chinese fir forest and the pine forest exhibited lower overall benefits than natural forests including the broad‐leaved forest and the bamboo forest. To propose a suitable management strategy for the study region, method of spatial cluster analysis was used based on the four eco‐services at the subwatershed scale. The basin was divided into four management groups instead of treating the region as a homogenous management region. Finally, we proposed more specific and diverse management strategies to optimize forest benefits throughout the entire region. 相似文献