Characterization of culture supernatant proteins from Brucella abortus and its protection effects against murine brucellosis

In this study, we characterized the secreted proteins of Brucella abortus into the enriched media under the bacterial laboratory growth condition and investigated the pathogenic importance of culture supernatant (CS) proteins to B. abortus infection. CS proteins from stationary phase were concentrated and analyzed using 2D electrophoresis. In MALDI TOF/TOF analysis, more than 27 proteins including CuZn SOD, Dps, Tat, OMPs, Adh, LivF, Tuf, SucC, GroEL and DnaK were identified. Cytotoxic effects of CS proteins were found to increase in a dose-dependent manner in RAW 264.7 cells. Upon B. abortus challenge into phagocytes, however, CS proteins pre-treated cells exhibited lower bacterial uptake and intracellular replication compared to untreated cells. Immunization with CS proteins induced a strong humoral and cell mediated immune responses and exhibited significant higher degree of protection against virulence of B. abortus infection compared to mice immunized with Brucella broth protein (BBP). Taken together, these results indicate that B. abortus secreted a number of soluble immunogenic proteins under laboratory culture condition, which can promote antibody production resulted in enhancing host defense against to subsequently bacterial infection. Moreover, further analysis of CS proteins may help to understand the pathogenic mechanism of B. abortus infection and host–pathogen interaction.     

Characterization of betaine aldehyde dehydrogenase (BetB) as an essential virulence factor of Brucella abortus

The pathogenic mechanisms of Brucellosis used to adapt to the harsh intracellular environment of the host cell are not fully understood. The present study investigated the in vitro and in vivo characteristics of B. abortus betaine aldehyde dehydrogenase (BetB) (Gene Bank ID: 006932) using a betB deletion mutant constructed from virulent B. abortus 544. In test under stress conditions, including osmotic- and acid stress-resistance, the betB mutant had a lower osmotic-resistance than B. abortus wild-type. In addition, the betB mutant showed higher internalization rates compared to the wild-type strain; however, it also displayed replication failures in HeLa cells and RAW 264.7 macrophages. During internalization, compared to the wild-type strain, the betB mutant was more adherent to the host surface and showed enhanced phosphorylation of protein kinases, two processes that promote phagocytic activity, in host cells. During intracellular trafficking, colocalization of B. abortus-containing phagosomes with LAMP-1 was elevated in betB mutant-infected cells compared to the wild-type cells. In mice, the betB mutant was predominantly cleared from spleens compared to the wild-type strain after 2 weeks post-infection, and the vaccination test with the live betB mutant showed effective protection against challenge infection with the virulent wild-type strain. These findings suggested that the B. abortus betB gene substantially affects the phagocytic pathway in human phagocytes and in host cells in mice. Furthermore, this study highlights the potential use of the B. abortus betB mutant as a live vaccine for the control of brucellosis.     

PRRSV特异性肽对CSF、PRRS免疫猪IFN-Y、IL-10分泌的影晌

应用PRRSV-GP5特异性肽刺激CSF、PRRS免疫猪外周血淋巴细胞,采用EI。IsA方法测定不同时间点淋巴细胞分泌IFN-7及IL-10的水平,分析PRRSv_GP5特异性肽刺激后,淋巴细胞培养上清中细胞因子的变化规律。结果显示,CSFV高抗PRRSV低抗体组于PRRSV免疫14d,肽刺激组中IFN-7水平显著高于对照组（P〈0．05）;其他组均差异不显著（P〉0．05）。PRRSV免疫14d,细胞培养24,72h后加PRRSV—GP5肽刺激,各组中试验组与对照组相比IL-10水平明显降低（P〈0．01）;PRRSV免疫28d,各组中肽刺激组与空白组相比,IL-10水平均无显著性差异（P〉0．05）。结果表明,PRRSV-GP5肽在PRRSV免疫早期可以促进IFN-7的分泌,并抑制IL-10的产生,但在免疫后期对淋巴细胞分泌的调节作用还需进-步研究。     

布鲁菌感染小鼠RAW264．7细胞对IRGl基因的表达调控作用

针对小鼠RAW264．7细胞IRGl基N设计4个RNA干扰靶位,筛选出最佳干扰序列构建shRNA慢病毒载体质粒并包装获得慢病毒颗粒,进而经嘌呤霉素筛选获得稳转细胞系,实现IRGl基因在RAW264．7细胞基因表达的沉默。并通过布鲁菌l6M株及M5株感染基因沉默细胞对IRGl基因在布鲁菌感染中的作用进行研究。结果表明,慢病毒介导的shRNA高效、稳定地沉默了IRGl基因的表达,布鲁菌侵染RAW264．7细胞后IRGl基因表达上调。未试验为1RG1基因及相美调控基因抗布鲁菌病作用研究奠定了基础。     

核桃高枝嫁接技术初探

在核桃的品种化栽培过程中,嫁接繁殖是一个重要的技术措施。但由于核桃体内含有单宁物质,使其嫁接成活率一直不高,多年来徘徊在10%左右。通过多年的实践探索,总结出春季核桃高枝嫁接——采用多头插皮舌接的嫁接方法,并对接穗、砧木进行适宜的处理,可使核桃嫁接成活率达到80%以上,为我市核桃品种化栽培提供了技术支撑。     

Fire performance of carbonized medium density fiberboard manufactured at different temperatures

Authors established a new manufacturing technology for crack-free carbonized boards by pressing and carbonizing the medium-density fiberboard. Industrialization of new functional carbon materials was performed by investigating the fundamental properties of the carbonized boards. To be used as a construction material, the carbonized board needs to satisfy the fire performance regulation. In this study, the carbonized boards were manufactured from medium-density fiberboard (c-MDF) at different temperatures and then fire performance including flame retardancy and smoke toxicity was analyzed using a cone calorimeter and noxious gas analyzer. The results show that as the carbonization temperature increases, weight loss ratio decreases and flame retardancy increases. In the c-MDF at 800 and 1000 °C, no external damage was observed after combustion. These c-MDFs satisfy the total heat release (standard below 8 MJ/m²) and heat release rate (standard below 200 kW/m²) regulations according to the Building Standard Law of Korea and Japan. In addition, the c-MDFs showed the lower total smoke release (TSR, 0.213 m²/m²) than that of virgin MDF (94.281 m²/m²). The c-MDF at 800 and 1000 °C were, therefore, classified as a class III flame retardancy material and can be used as indoor finishing material.     

凤眼莲动态模块化治理湖泊污染的设计

指出了环境生态工程采用生态学理论,强调将环境问题于系统内解决,使受污染的环境能够适时与周边的大自然友好和谐地融为一体,注重经济效益和生态效益的高度统一,已经逐步发展为最受欢迎的修复水体的技术之一。凤眼莲是修复污染湖泊的良好先锋植物,但其易泛滥成灾和含水量甚高的特性限制了人们对其大规模的使用。本着环境生态工程的理念,建立了凤眼莲动态模块化的浮床装置,利用风能为浮床装置提供电能,结合装置内的螺旋桨动力结构使浮床移动,通过旋转吊臂滑轮和底部尼龙网结构使凤眼莲机械化原位去水。此设计在实现低廉、高效治理水体富营养化和重金属等污染问题的同时,也有效解决了凤眼莲可能泛滥成灾的隐患,达到生态效益、经济效益和景观效益的协调统一。     

丹参地上部分正丁醇萃取部位化学成分检测及其抗脑缺血研究

筛选丹参地上部分抗脑缺血的活性部位,并检测其所含化学成分,对丹参的开发和利用具有重要意义。采用D101大孔吸附树脂吸附丹参地上部分正丁醇萃取部位,将其分离纯化为多个部位。以昆明小鼠常压缺氧模型和不完全性脑缺血模型筛选有效部位;将筛选出的活性部位再用聚酰胺柱分离为不同部位,选用上述模型进行活性部位筛选;并用高效液相检测筛选的活性部位所含化学成分。结果表明:D-101大孔树脂经体积分数为50%和75%乙醇洗脱部位能显著增加小鼠常压耐缺氧时间,延长小鼠全脑缺血后的存活时间(P0.01);聚酰胺柱分离后的水洗部位可显著增加小鼠常压耐缺氧时间和小鼠全脑缺血后的存活时间(P0.01);高效液相检测聚酰胺柱分离的水洗部位含有原儿茶醛、咖啡酸、丹参素。丹参地上部分正丁醇萃取部位聚酰胺柱分离的水洗部位为有效部位,检测出有效成分为原儿茶醛、咖啡酸、丹参素。     

哈密产黄鳝的染色体组型分析

哈密产黄鳝的染色体组型分析王秀玲，吴敏，马英梅，刘伟，史为慧（新疆师范大学生物系，乌鲁木齐，８３００５３）关键词哈密产黄鳝，核型，分类ＡＮＡＬＹＳＩＳＯＦＫＡＲＹＯＴＹＰＥＯＦＭＯＮＯＰＴＥＲＵＳＡＬＢＵＳＩＮＨＡＭＩ￥ＷａｎｇＸｏｕｌｉｎｇ；ＷｕＭ...