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991.
抗原纯净度是口蹄疫(Foot-and-mouthdisease,FMD)灭活疫苗质量检验的一项重要内容,一般采用疫苗2–3次免疫动物后,检测非结构蛋白(Non-structuralprotein,NSP)抗体是否阳转,判断疫苗抗原的纯净度。文中旨在建立定量检测FMD灭活疫苗抗原中NSP3AB含量的ELISA方法,为疫苗质量控制提供参考方法。利用口蹄疫病毒(Foot-and-mouthdiseasevirus,FMDV)NSP3A单克隆抗体和辣根过氧化物酶(Horseradish peroxidase,HRP)标记的3B单克隆抗体,建立定量检测NSP3AB含量的双抗体夹心ELISA检测方法。采用原核表达并纯化的3AB蛋白作为标准品,标准品系列稀释,绘制标准曲线,以标准品与未加抗原的阴性对照吸光值(OD)的比值大于2.0的标准品最低浓度为最低检测限。标准品浓度介于4.7–600.0 ng/mL之间时,测得的OD值与浓度呈线性相关,回归曲线呈直线,相关系数R2=0.99,确定最低检测限为4.7ng/mL。检测12份未纯化灭活抗原中3AB蛋白含量介于9.3–200.0ng/mL之间;而纯化后的... 相似文献
992.
近年来,质谱技术在膜蛋白结构与功能研究中被广泛应用。由于膜蛋白的跨膜结构域含有大量疏水性氨基酸,常常导致液质串联质谱检测的序列覆盖率较低,从而限制了质谱技术在膜蛋白结构与功能研究中的应用。文中利用人的整合膜蛋白维生素K环氧化物还原酶为模型,优化胶内消化条件,建立了一种稳定提高膜蛋白质谱序列覆盖率的糜蛋白酶胶内消化方法。通过探索钙离子浓度、pH值和缓冲体系对序列覆盖率、检测特异肽段的总数和类型以及特异肽段大小的影响,发现在5–10 mmol/L钙离子浓度、pH 8.0–8.5的Tris-HCl缓冲液中,可以兼顾序列覆盖率和肽段的多样性。该方法可以使膜蛋白的质谱覆盖率达到80%以上,将在膜蛋白结构与功能、膜蛋白相互作用位点的鉴定以及膜蛋白与小分子药物结合位点的鉴定等研究中具有广泛的应用价值。 相似文献
993.
微小型生物反应器体积微小但在线分析检测和过程控制功能媲美台式装备。其核心支撑技术包括一次性材料及微加工技术、非接触式光学传感器、自动化以及实验设计(DOE)、数据分析软件与过程控制的整合。由于体积微小、湍流程度和单位能耗较低,微小型反应器内的混合、传质、剪切特性与工业规模设备有一定的区别。现阶段微小型生物反应器主要用于菌株和细胞系筛选和工艺优化,在实现高通量工艺的同时确保了数据的丰度,对缩短研发周期和加速产品上市,尤其是在应对突发性传染性疾病方面有着重要的意义。未来,精准医疗概念的落实也依赖功能柔性化的微小型生物反应器系统。 相似文献
994.
Zetian Lai Jing Wu Xiaolin Xiao Lihua Xie Tong Liu Jingni Zhou Ye Xu Yiquan Cai Feng Lin Bin Li Lu Gan Anthony A. James Xiao-Guang Chen 《PLoS neglected tropical diseases》2022,16(9)
BackgroundThe surveillance of vector mosquitoes is essential for prevention and control of mosquito-borne diseases. In this study, we developed an internet-based vector mosquito monitor, MS-300, and evaluated its efficiency for the capture of the important vector mosquitoes, Aedes albopictus and Culex quinquefasciatus, in laboratory and field trials.Methodology/Principal findingsThe linear sizes of adult Ae. albopictus and Cx. quinquefasciatus were measured and an infrared window was designed based on these data. A device to specifically attract these two species and automatically transmit the number of captured mosquitoes to the internet was developed. The efficiency of the device in capturing the two species was tested in laboratory, semi-field and open field trials. The efficiency results for MS-300 for catching and identifying Ae. albopictus in laboratory mosquito-net cages were 98.5% and 99.3%, and 95.8% and 98.6%, respectively, for Cx. quinquefasciatus. In a wire-gauze screened house in semi-field trials, the efficiencies of MS-300 baited with a lure in catching Ae. albopictus and Cx. quinquefasciatus were 54.2% and 51.3%, respectively, which were significantly higher than 4% and 4.2% without the lure. The real-time monitoring data revealed two daily activity peaks for Ae. albopictus (8:00–10:00 and 17:00–19:00), and one peak for Cx. quinquefasciatus (20:00–24:00). During a 98-day surveillance trial in the field, totals of 1,118 Ae. albopictus and 2,302 Cx. quinquefasciatus were captured by MS-300. There is a close correlation between the number of captured mosquitoes and the temperature in the field, and a positive correlation in the species composition of the captured samples among the mosquitoes using MS-300, BioGents Sentinel traps and human landing catches.Conclusions/SignificanceThe data support the conclusion that MS-300 can specifically and efficiently capture Ae. albopictus and Cx. quinquefasciatus, and monitor their density automatically in real-time. Therefore, MS-300 has potential for use as a surveillance tool for prevention and control of vector mosquitoes. 相似文献
995.
Li Bai Wang Lu Shan Tang Huixin Tang Manman Xu Chen Liang Sujun Zheng Shuang Liu Ming Kong Zhongping Duan Yu Chen 《Cell death & disease》2022,13(9)
We previously documented that M2-like macrophages exert a hepatoprotective effect in acute-on-chronic liver failure (ACLF) by inhibiting necroptosis signalling. Nevertheless, the molecular mechanism behind this hepatoprotection still needs to be further dissected. Galectin-3 (GAL3) has been reported to be critically involved in the pathogenesis of multiple liver diseases, whereas the potential role of GAL3 in ACLF remains to be explored. Herein, we hypothesised that GAL3 plays a pivotal role in the hepatoprotection conferred by M2-like macrophages in ACLF by inhibiting necroptosis. To test this hypothesis, we first assessed the expression of GAL3 in control and fibrotic mice with or without acute insult. Second, loss- and gain-of-function experiments of GAL3 were performed. Third, the correlation between GAL3 and M2-like macrophage activation was analysed, and the potential role of GAL3 in M2-like macrophage-conferred hepatoprotection was confirmed. Finally, the molecular mechanism underlying GAL3-mediated hepatoprotection was dissected. GAL3 was found to be obviously upregulated in fibrotic mice with or without acute insult but not in acutely injured mice. Depletion of GAL3 aggravated hepatic damage in fibrotic mice upon insult. Conversely, adoptive transfer of GAL3 provided normal mice enhanced resistance against acute insult. The expression of GAL3 is closely correlated with M2-like macrophage activation. Through adoptive transfer and depletion experiments, M2-like macrophages were verified to act as a major source of GAL3. Importantly, GAL3 was confirmed to hold a pivotal place in the hepatoprotection conferred by M2-like macrophages through loss- and gain-of-function experiments. Unexpectedly, the depletion and adoptive transfer of GAL3 resulted in significant differences in the expression levels of pyroptosis but not necroptosis signalling molecules. Taken together, GAL3 plays a pivotal role in the hepatoprotection conferred by M2-like macrophages in ACLF by inhibiting pyroptosis but not necroptosis signalling. Our findings provide novel insights into the pathogenesis and therapy of ACLF.Subject terms: Inflammasome, Necroptosis 相似文献
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998.
Infection of humans with hepatitis B virus(HBV)not only leads to hepatitis,cirrhosis,and liver cancer but also causes extrahep-atic damage,such as diabetes,kidn... 相似文献
999.
Long noncoding RNAs(IncRNAs)act as essential regulators of various diseases.However,the func-tions of IncRNAs in sepsis-induced acute lung injury(SALI)remain un... 相似文献
1000.