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Jiaming Tian Bingxin Dai Li Gong Pingping Wang Han Ding Siwei Xia Weice Sun Cuiping Ren Jijia Shen Miao Liu 《PLoS neglected tropical diseases》2022,16(8)
Schistosomiasis is a serious and widespread parasitic disease caused by infection with Schistosoma. Because the parasite’s eggs are primarily responsible for schistosomiasis dissemination and pathogenesis, inhibiting egg production is a potential approach to control the spread and severity of the disease. The bromodomain and extra-terminal (BET) proteins represent promising targets for the development of epigenetic drugs against Schistosoma. JQ-1 is a selective inhibitor of the BET protein family. In the present study, JQ-1 was applied to S. japonicum in vitro. By using laser confocal scanning microscopy and EdU incorporation assays, we showed that application of JQ-1 to worms in vitro affected egg laying and the development of both the male and female reproductive systems. JQ-1 also inhibited the expression of the reproductive-related genes SjPlk1 and SjNanos1 in S. japonicum. Mice infected with S. japonicum were treated with JQ-1 during egg granuloma formation. JQ-1 treatment significantly reduced the size of the liver granulomas and levels of serum alanine aminotransferase and aspartate aminotransferase in mice and suppressed both egg laying and the development of male and female S. japonicum reproductive systems in vivo. Moreover, the mRNA expression levels of some proinflammatory cytokines were decreased in the parasites. Our findings suggest that JQ-1 treatment attenuates S. japonicum egg–induced hepatic granuloma due at least in part to suppressing the development of the reproductive system and egg production of S. japonicum. These findings further suggest that JQ-1 or other BET inhibitors warrant additional study as a new approach for the treatment or prevention of schistosomiasis. 相似文献
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Ruijun Liu Ruili Liu Zhiyi Guo Jianghao Ren Jia Huang Qingquan Luo Qiang Tan 《Cell death & disease》2022,13(8)
In view of the important roles played by Kinetochore proteins in mitosis, we believed that they may contribute to the development and progression of human cancers, which has been reported recently elsewhere. Kinetochore-associated 1 (KNTC1) participates in the segregation of sister chromatids during mitosis, the effects of which on non-small-cell lung cancer (NSCLC) remain unclear. Here, we sought to identify the biological significance of KNTC1 in NSCLC. KNTC1 protein expression in NSCLC tissues was investigated by immunohistochemistry. Lentivirus delivered short hairpin RNA (shRNA) was utilized to establish KNTC1 silence NSCLC cell lines. The effects of KNTC1 depletion on NSCLC cell proliferation, migration, apoptosis, and tumor formation were analyzed by MTT assay, wound-healing assay, transwell assay, flow cytometry assay, and in nude mouse models in vivo. After KNTC1 reduction, NSCLC cell viability, proliferation, migration, and invasion were restrained. A xenograft tumor model was also provided to demonstrate the inhibited tumorigenesis in NSCLC. In addition, the downstream mechanism analysis indicated that KNTC1 depletion was positively associated with PSMB8. The findings of the present study suggested that KNTC1 may have a pivotal role in mediating NSCLC progression and may act as a novel therapeutic target for NSCLC.Subject terms: Non-small-cell lung cancer, Cell migration 相似文献
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Electron acceptors for anaerobic oxidation of methane drive microbial community structure and diversity in mud volcanoes 下载免费PDF全文
Ge Ren Anzhou Ma Yanfen Zhang Ye Deng Guodong Zheng Xuliang Zhuang Guoqiang Zhuang Danielle Fortin 《Environmental microbiology》2018,20(7):2370-2385
Mud volcanoes (MVs) emit globally significant quantities of methane into the atmosphere, however, methane cycling in such environments is not yet fully understood, as the roles of microbes and their associated biogeochemical processes have been largely overlooked. Here, we used data from high‐throughput sequencing of microbial 16S rRNA gene amplicons from six MVs in the Junggar Basin in northwest China to quantify patterns of diversity and characterize the community structure of archaea and bacteria. We found anaerobic methanotrophs and diverse sulfate‐ and iron‐reducing microbes in all of the samples, and the diversity of both archaeal and bacterial communities was strongly linked to the concentrations of sulfate, iron and nitrate, which could act as electron acceptors in anaerobic oxidation of methane (AOM). The impacts of sulfate/iron/nitrate on AOM in the MVs were verified by microcosm experiments. Further, two representative MVs were selected to explore the microbial interactions based on phylogenetic molecular ecological networks. The sites showed distinct network structures, key species and microbial interactions, with more complex and numerous linkages between methane‐cycling microbes and their partners being observed in the iron/sulfate‐rich MV. These findings suggest that electron acceptors are important factors driving the structure of microbial communities in these methane‐rich environments. 相似文献
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基于遥感和GIS的川西绿被时空变化研究 总被引:4,自引:0,他引:4
探索出了利用多时相MODIS数据分析绿被时空变化的技术方法,揭示出了川西2002—2008年间绿被的变化特征。建立了绿被提取模型。用其从2002—2008年的多期MODIS影像中提取出川西多期绿被数据。其次,利用GIS技术对2002—2008年间绿被变化,及其与温度、降雨的关系等进行了分析。研究表明:2002年绿被天数在195 d以上的区域有43.3%。终年无绿被的区域有4.3%。西北部植被生长日数短,而东南部生长日数长。2002—2008年间,春季绿被面积变幅最大,秋季最小。最大绿被面积出现在2006年的夏季,最小绿被面积出现在2005年的冬季。平均夏冬绿被面积差占区域面积46.7%。在季节上,绿被面积与温度和降雨量均在0.01的水平上呈显著正相关关系,其相关系数分别为0.82和0.84。该研究成果对植被生长潜力挖掘、农牧生产和生态建设决策等均有重要意义。 相似文献
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本文对北京西山海拔300米的26年生人工栓皮栎林的生物量作了测定。粮据十株伐倒的标准木分别取得乔木各部分的干重。采用W=a(D2H)b的幂函数方程,获得每公顷土地上的树干重32.16吨,枝条重9.85吨、叶重1.68吨、根重9.95吨。对灌木和草本植物采用收割法作测定:灌木的地上部分每公顷为1.33吨,地下部分为2.3吨;草本植物的地上部分每公顷为0.15吨,地下部分为0.8吨。所以栓皮栎的地上部分总生物量每公顷为45.17吨,地下部分13.05吨,总计58.22吨。 相似文献
40.
Qizhang Long Wenwei Zhang Peng Wang Wenbiao Shen Tong Zhou Nannan Liu Ren Wang Ling Jiang Jiexue Huang Yihua Wang Yuqiang Liu Jianmin Wan 《Journal of Plant Biology》2013,56(4):232-242
Lipoxygenases (LOXs) are enzymes involved in lipid peroxidation. Here we reported the identification, molecular and functional characterization of the gene encoding rice (Oryza sativa L.) seed LOX3 (sLOX3). Via a map-based cloning strategy we identified Os03g0700400 as the candidate gene encoding sLOX3. Further functional complementary test and biochemical characterization of the recombinant Os03g0700400 protein verified the identification. The sLOX3 gene was highly expressed in roots, moderately in embryos and very weakly in leaves, leaf sheaths and stems. Transient expression experiment (in rice protoplasts) and subsequent laser confocal microscopic analysis demonstrated that the sLOX3 protein was localized into the cytosol. We next showed that overexpression of sLOX3 in a japonica sLOX3-normal rice cultivar, Wuyunjing 7 accelerated the decrease of seed germination ability when the seeds were routinely stored, which demonstrated that sLOX3 had a negative effect on seed longevity (storability). Meanwhile, an increased occurrence of embryo decay was observed in the same transgenic seeds, suggesting that sLOX3 might negatively affect seed longevity by facilitating colonization of particular seed pathogens. Our result forwarded the understanding of the effects of 9-LOX on rice seed longevity. 相似文献