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991.
Qian Cao Zhe-Man Xiao Xi Wang Chao Weng Man Ding Fan Zhu Zu-Neng Lu 《Neurochemical research》2018,43(6):1227-1241
The existing data about whether acid sensing ion channels (ASICs) are proconvulsant or anticonvulsant are controversial. Particularly, acid sensing ion channel 3 (ASIC3) is the most sensitive to extracellular pH and has the characteristic ability to generate a biphasic current, but few studies have focused on the role of ASIC3 in seizure. Here we found ASIC3 expression was increased in the hippocampus of pilocarpine induced seizure rats, as well as in hippocampal neuronal cultures undergoing epileptiform discharge elicited by Mg2+-free media. Furthermore, ASIC3 blockade by the selective inhibitor APETx2 shortened seizure onset latency and increased seizure severity compared with the control in the pilocarpine induced seizure model. Incubation with APETx2 enhanced the excitability of primary cultured hippocampal neurons in Mg2+-free media. Notably, the aggravated seizure was associated with upregulation of the N-methyl-d-aspartate subtype of glutamate receptors (NMDARs), increased NMDAR mediated excitatory neurotransmission and subsequent activation of the Ca2+/calmodulin-dependent protein kinase II (CaMKII) and cAMP-response element binding protein (CREB) signaling pathway. Moreover, co-immunoprecipitation confirmed the interaction between ASIC3 and NMDAR subunits, and NMDARs blockade prevented the aggravated seizure caused by ASIC3 inhibition. Taken together, our findings suggest that ASIC3 inhibition aggravates seizure and potentiates seizure induced hyperexcitability at least partly by the NMDAR/CaMKII/CREB signaling pathway, which implies that ASIC3 agonists may be a promising approach for seizure treatment. 相似文献
992.
Hewei Zhang Mingqi Xia Wei Wang Decai Ju Long Cao Bai Wu Xin Wang Ying Wu Ni Song Jiaxin Hu Changxiao Tian Shucheng Zhang Hua Wu 《中国病毒学》2018,33(2):153-161
A novel PRRSV strain was isolated in China that was genetically similar to the NADC30 strain which is reported to have spread throughout China. The objective of the present study was to evaluate the cross-protective efficacy of the live vaccine TJM-F92 in young pigs against challenge with a NADC30-like strain, HN201605. Twenty-five PRRSV- and antibody-free pigs were randomly divided into the following five groups: Vac/ChA, Unvac/ChA, Vac/ChB, Unvac/ChB and the mock. The pigs in groups Vac/ChA and Vac/ChB were inoculated intramuscularly with 1 mL TJM-F92 (105.0 TCID50/mL). At 28 days post vaccination (0 days post challenge), groups Vac/ChA and Unvac/ChA were inoculated intranasally with 104.5 TCID50/mL PRRSV strain TJ F3 (2 mL/pig), while groups Vac/ChB and Unvac/ChB were inoculated, using the same route, with the same dose of the NADC30-like strain HN201605 F3. Protective effects of the PRRSV strain were observed in all pigs in the Vac/ChA and Vac/ChB groups. Neither high fever nor signs of clinical disease were observed through the experiment in these groups, whereas pigs in Unvac/ChA group exhibited serious clinical symptoms, pathological lesions, and weight loss. In Unvac/ChB group, pigs developed milder clinical symptoms, which demonstrated that the NADC30-like strain HN201605 had moderate pathogenicity. The results suggest that the MLV vaccine strain TJM-F92 is an effective and safe vaccine candidate for use in China. 相似文献
993.
Pan Chen Fan Yang Weijun Cao Huanan Liu Keshan Zhang Xiangtao Liu Zhiwen Xu Zixiang Zhu Haixue Zheng 《中国病毒学》2018,33(5):394-401
Seneca Valley virus (SVV), a newly determined etiological agent of vesicular disease in swine, causes porcine idiopathic disease and occasional acute death in piglets. Recently, an increased number of SVV infection cases have been reported in the United States (US) and China, resulting in significant economic losses to the swine industry. The first identification of SVV in China was reported in Guangdong Province, a major swine producing province. The cases of SVV were continuously reported in Guangdong in 2015 and 2016. However, the spread of SVV in Guangdong in 2017 remains unknown.In this study, we determined two new SVV strains, CH-GD-2017-1 and CH-GD-2017-2, from Guangdong. The genetic analysis suggested that the two Guangdong strains showed different characteristics to previous Guangdong strains. They showed lower nucleotide similarity with strains isolated in 2015 and 2016, and were more similar to the US strains.Phylogenetic analyses indicated that the new strains were clustered in a different clade with previous Guangdong strains.We found 28 mutated amino acids in the new strains, compared with the first Guangdong strain, SVV CH-01-2015. In the geographic analysis, we found that the US and China reported more SVV cases than other countries, and most of the SVV cases were reported in east and central China—of which, Guangdong Province is one of the major epidemic regions. In conclusion, our findings indicate that SVV continued to spread in Guangdong Province in 2017, and two different clades of SVVs have emerged in this region. 相似文献
994.
Dengyuan Zhou Fan Jia Qiuyan Li Luping Zhang Zheng Chen Zikai Zhao Min Cui Yunfeng Song Huanchun Chen Shengbo Cao Jing Ye 《中国病毒学》2018,33(6):515-523
Japanese encephalitis virus(JEV) is a mosquito-borne virus and the major cause of viral encephalitis in Asia. NS1', a52-amino acid C-terminal extension of NS1, is generated with a-1 programmed ribosomal frameshift and is only present in members of the Japanese encephalitis serogroup of flaviviruses. Previous studies demonstrated that NS1' plays a vital role in virulence, but the mechanism is unclear. In this study, an NS1' defected(rG66A) virus was generated. We found that rG66A virus was less virulent than its parent virus(pSA14) in wild-type mice. However, similar mortality caused by the two viruses was observed in an IFNAR knockout mouse model. Moreover, we found that rG66A virus induced a greater type Ⅰ interferon(IFN) response than that by pSA14, and JEV NS1' significantly inhibited the production of IFN-b and IFN-stimulated genes. Taken together, our results reveal that NS1' plays a vital role in blocking type I IFN production to help JEV evade antiviral immunity and benefit viral replication. 相似文献
995.
Chao Han Fangchao Liu Xueli Yang Jichun Chen Jianxin Li Jie Cao Ying Li Chong Shen Ling Yu Zhendong Liu Xianping Wu Liancheng Zhao Dongshen Hu Xiangfeng Lu Xigui Wu Dongfeng Gu 《中国科学:生命科学英文版》2018,61(5):504-514
Existing evidence on the relationship between cardiovascular health(CVH) metrics and cardiovascular disease(CVD) was primarily derived from western populations. We aimed to evaluate the benefits of ideal CVH metrics on preventing incident atherosclerotic CVD(ASCVD) in Chinese population. This study was conducted among 93,987 adults from the China-PAR project(Prediction for ASCVD Risk in China) who were followed up until 2015. Cox proportional hazard regression models were used to estimate the hazard ratios(HRs) and their corresponding 95% confidence intervals(CIs) of CVH metrics for the risk of ASCVD, including coronary heart disease(CHD), stroke and ASCVD death. We further estimated the population-attributable risk percentage(PAR%) of these metrics in relation to each outcome. We observed gradient inverse associations between the number of ideal CVH metrics and ASCVD incidence. Compared with participants having ≤2 ideal CVH metrics, the multivariable-adjusted HRs(95% CIs) of ASCVD for those with 3, 4, 5, 6 and 7 ideal CVH metrics were 0.83(0.74–0.93), 0.66(0.59–0.74), 0.55(0.48–0.61), 0.44(0.38–0.50) and 0.24(0.18–0.31), respectively(P for trend 0.0001). Approximately 62.1% of total ASCVD, 38.7% of CHD, 66.4% of stroke, and 60.5% of ASCVD death were attributable to not achieving all the seven ideal CVH metrics. After adjusting effects of ideal health factors, having four ideal health behaviors could independently bring adults health benefits in preventing 17.4% of ASCVD, 18.0% of CHD, 16.7% of stroke, and 10.1% of ASCVD death. Among all the seven CVH metrics, to keep with ideal blood pressure(BP) implied the largest public health gains against various ASCVD events(PAR% between 33.0% and 47.2%), while ideal diet was the metric most difficult to be achieved in the long term. Our study indicates that the more ideal CVH metrics adults have, the less ASCVD burden there is in China. Special efforts of health education and behavior modification should be made on keeping ideal BP and dietary habits in general Chinese population to prevent the epidemic of ASCVD. 相似文献
996.
Tao Li Xuehui Fan Yiyan Yu Linlin Chen Wenjun Huang Yan Yang Jimin Cao Xiaorong Zeng Xiaoqiu Tan 《中国科学:生命科学英文版》2018,61(5):599-603
正Dear Editor,Small conductance Ca2+-activated potassium (SK) channels are widely expressed in various tissues and play a unique role in regulating cell function by integrating cytosolic Ca2+ levels and membrane potential (Adelman et al., 2012). Xu et al. first identified SK channels in the heart and found that SK channels, particularly the SK2 channel, are preferentially expressed in human and mouse atrial myocytes but not in ventricular myocytes (Xu et al., 2003). This suggests that the SK 相似文献
997.
正Cotton is not only an important cash crop for its fiber,but also an excellent model system for studying polyploidization,cell elongation and cell wall biosynthesis(Yang et al.,2014;Fang et al.,2017;Wang et al.,2016;Zou et al.,2016).A focus for scientists is to dissect the genetic basis underlying important agronomic traits(Gong et al.,2018;Huang et al.,2016).The advent of high-throughput sequencing technologies has boosted unveiling the cotton genome(Wang et al.,2012;Li et al.,2014;Li et al.,2015).High-throughput 相似文献
998.
SPOCK1 promotes the invasion and metastasis of gastric cancer through Slug‐induced epithelial‐mesenchymal transition 下载免费PDF全文
Guiyuan Liu Yinghai Zhao Gan Cao Qinghong Liu 《Journal of cellular and molecular medicine》2018,22(2):797-807
Metastasis is a crucial impediment to the successful treatment for gastric cancer. SPOCK1 has been demonstrated to facilitate cancer metastasis in certain types of cancers; however, the role of SPOCK1 in the invasion and metastasis of gastric cancer remains elusive. SPOCK1 and epithelial‐mesenchymal transition (EMT)‐related biomarkers were detected by immunohistochemistry and Western blot in gastric cancer specimens. Other methods including stably transfected against SPOCK1 into gastric cancer cells, Western blot, migration and invasion assays in vitro and metastasis assay in vivo were also performed. The elevated expression of SPOCK1 correlates with EMT‐related markers in human gastric cancer tissue, clinical metastasis and a poor prognosis in patients with gastric cancer. In addition, knockdown of SPOCK1 expression significantly inhibits the invasion and metastasis of gastric cancer cells in vitro and in vivo, inversely, SPOCK1 overexpression results in the opposite effect. Interestingly, SPOCK1 expression has no effect on cell proliferation in vitro and in vivo. Regarding the mechanism(s) of SPOCK1‐induced cells invasion and metastasis, we prove that Slug‐induced EMT is involved in SPOCK1‐facilitating gastric cancer cells invasion and metastasis. The elevated SPOCK1 expression is closely correlated with cancer metastasis and patient survival, and SPOCK1 promotes the invasion and metastasis of gastric cancer through Slug‐mediated EMT, thereby possibly providing a novel therapeutic target for gastric cancer. 相似文献
999.
Jie?PanEmail author Duan-lin?Cao Fu-de?Ren Jian-long?Wang Lu?Yang 《Journal of molecular modeling》2018,24(10):298
In order to reveal the mechanism of drug action and design of DNA/RNA-targeted drugs containing aromatic rings, the cooperativity effects between the intermolecular π???π and H-bonding interactions in curcumin(drug)???cytosine(DNA/RNA base)???H2O were investigated by the B3LYP-D3 and MP2(full) methods with the 6–311++G(2d,p) basis set. The π???π interaction plays an important role in stabilizing the linear ternary complexes with the cooperativity effects, and the cyclic structures suffer the anticooperativity effects. The cooperativity or anticooperativity effects are notable, which could lead to a possible significant change in drug activity. The hydration is essentially the cooperativity or anticooperativity effect. These results were confirmed by the atoms in molecules (AIM), reduced density gradient (RDG), and surface electrostatic potentials analyses. The cyclic complexes are more stable, from which it can be deduced that the drug always links with the DNA/RNA base and H2O by the π???π or H-bonding interactions, and only in this way can the drug activity be shown. Therefore, the designed DNA/RNA-targeted drugs should possess a certain number of hydrophilic groups in contact with the DNA/RNA base and H2O to reconcile drug activity by the cooperativity effect between the π???π and H-bonding interactions, as is in agreement with many of the drugs in use. 相似文献
1000.
Juan Niu Da Cao Haoxian Li Hui Xue Lina Chen Beibei Liu Shangyin Cao 《Tree Genetics & Genomes》2018,14(1):14
In pomegranate (Punica granatum), seed hardness is an important trait directly affecting fruit marketability. However, seed formation in pomegranate has not been well studied. We investigated the genetic mechanism underlying pomegranate seed hardness by comparing protein expression profiles between soft- and hard-seeded varieties 60 and 120 days after flowering. We identified 1940 proteins, of which 399 were differentially expressed. Most of the differentially expressed proteins were involved in posttranslational modification and carbohydrate metabolism. Cell wall biosynthesis, which showed positive correlations with seed hardness, was selected as the candidate pathway. The mRNA levels of 14 proteins involved in cell wall biosynthesis were further analyzed by qPCR. Lignin biosynthesis-related differentially expressed proteins showed lower expression at protein and gene levels in a soft-seeded variety at the early stages. Moreover, cellulose biosynthesis-related differentially expressed proteins showed higher expression levels in the soft-seeded variety at 60 days after flowering. Thus, the soft-seeded variety showed lower lignin but higher cellulose biosynthesis at the early fruit developmental stage, suggesting that lignin and cellulose play opposing roles in cell wall formation in pomegranate seeds. Moreover, differentially expressed proteins involved in cell wall degradation showed higher expression levels in the soft-seeded variety at both developmental stages. These results suggested that differences in seed hardness between soft- and hard-seeded pomegranates might result from cell wall biosynthesis and also be affected by cell wall degradation. The present proteome-wide profiling of pomegranate genotypes with contrasting seed hardness adds to the current knowledge base of the molecular basis of seed hardness development. 相似文献