Gene therapy for hemophilia B mediated by recombinant adeno-associated viral vector with hFIXR338A, a high catalytic activity mutation of human coagulation factor IX

A mutant human factor IX with arginine at 338 residual changed to alanine (hFIXR338A) by site-directed mutagenesis was introduced into AAV vectors, and a recombinant adeno-associ- ated viral vector containing hFIXR338A, prepared by rHSV/AAV hybrid helper virus system, was directly introduced to the hind leg muscle of factor IX knock out mice. The expression and the biological activity of human factor IX mutant, hFIXR338A, and the immune response against it in the treated mice were assayed and detected. The results showed that (i) the high-level expression of human factor IX mutant protein, hFIXR338A, has been detected in rAAV-hFIXR338A treated hemophilia B mice and lasted more than 15 weeks; (ii) the clotting activity of hFIXR338A in plasma is 34.2%± 5.23%, which is remarkably higher than that of (14.27% ± 3.4%) of wild type hFIX treated mice in the activated partial thromboplastin assay; (iii) immune response against factor IX R338A was absent, with no factor IX mutant protein (hFIXR338A) inhibitors development in the treated mice; and (iv) no local or systemic side-effects and toxicity associated with the gene transfer were found. It demonstrated the potential use of treating hemophilia B by recombinant adeno-associated viral vectors with mutant hFIXR338A gene, an alternative strategy for hemophilia B gene therapy to wild-type human factor IX.     

一些抗癌药物对荷瘤小鼠血清中唾液酸含量的影响

测定荷六种小鼠肿瘤S180肉瘤(实体型和腹水型),腹水肝癌(HepA),艾氏腹水瘤(EC),白血病P388和Lewis肺癌的小鼠腹水和血清中唾液酸含量,结果显示血清中唾液酸含量与肿瘤生长、肿瘤类型有关。腹水中唾液酸含量高,推测肿瘤能比正常组织产生更多唾液酸。对四种腹水肿瘤用阴离子交换树脂层析鉴定,发现HepA腹水中葡萄糖代唾液酸(NcuGc)含量明显低于其它三种腹水瘤。还研究了十几种抗癌药物对荷S180和Lewis肺癌小鼠血清中唾液酸含量的影响。发现吗丙嗪(probimane)和顺铂(DDP)能降低荷瘤小鼠血清中唾液酸含量,提示此二药物在肿瘤治疗中更具选择性。     

蛋白质剪接与一类新的可移动遗传因子

最近在几种生物体中连续发现了蛋白质剪接现象,由于它与通常所说的RNA剪接的区别,人们称这些在蛋白质水平被剪切掉的部分为“蛋白质内含子”.有些蛋白质内含子具有核酸内切酶功能,编码蛋白质内含子的DNA片段是一类新的可移动遗传因子.文中介绍了目前发现的几例蛋白质剪接现象,讨论了蛋白质剪接的可能机理,分析了蛋白质内含子的进化及其生物学意义.     

基于CRISPR/Cas9系统构建TIA1基因突变的人诱导多能干细胞系

利用CRISPR/Cas9基因编辑技术构建TIA1-P362L突变的人诱导多能干细胞(iPSCs)系,并使其分化为运动神经元,为研究TIA1突变导致肌萎缩侧索硬化症(ALS)的分子机制及药物筛选提供细胞模型。利用CRISPR在线工具设计sgRNA,将其构建到pX330载体中,扩增左右同源臂并将其构建到供体载体中,接着对该供体载体的靶位点进行突变以获得同源重组的Donor质粒。将sgRNA和Donor质粒同时电转到野生型iPSCs系C11中,经G418抗性筛选获得单克隆,利用PCR和Sanger测序鉴定基因型,采用Western blot鉴定TIA1蛋白表达情况,并用核型分析、免疫荧光染色、定量反转录PCR及拟胚体(EBs)三胚层分化对TIA1-P362L突变的iPSCs系进行多能性鉴定,通过抑制SMAD信号通路诱导iPSCs分化为运动神经元并用特异性抗体验证。该研究成功建立具有TIA1-P362L突变的iPSCs系,该细胞系正常表达TIA1蛋白,具有多能性且能成功分化为运动神经元,对阐明TIA1在ALS疾病中的作用具有重要意义。     

球孢白僵菌与四唑虫酰胺联合应用对草地贪夜蛾的毒力研究

为了明确四唑虫酰胺与球孢白僵菌联合应用对草地贪夜蛾的防治效果,本研究选择了对草地贪夜蛾高毒力的球孢白僵菌Bb105株系和化学药剂四唑虫酰胺,开展了两者不同比例混配和不同使用顺序对草地贪夜蛾幼虫的毒力研究.球孢白僵菌与四唑虫酰胺不同配比对草地贪夜蛾毒力的研究结果表明,两者以9∶1和4∶1的比例混合使用时,共毒系数分别为738.50和421.19,表现出增效作用,且混用比例为9∶1时增效作用最明显.两者不同使用顺序对草地贪夜蛾的毒力测定结果表明,先使用球孢白僵菌72 h后再使用四唑虫酰胺对草地贪夜蛾的实际致死率比预测死亡率高,也表现出协同增效作用.研究结果为菌药联合防治草地贪夜蛾的实践应用奠定了良好的理论基础.     

PACAP27对Ⅱ型糖尿病诱导的睾丸损伤的保护作用

目的 研究垂体腺苷酸环化酶激活肽(pituitary adenylate cyclase-activating polypeptide,PACAP)对Ⅱ型糖尿病大鼠睾丸损伤的保护作用.方法 18只雄性SD大鼠随机平均分为对照组、Ⅱ型糖尿病组和Ⅱ型糖尿病PACAP27干预组3组.腹腔注射链脲霉素和60％高脂饲料喂食,建立...     

鸟类血红蛋白的四级结构和残基选择性特征

对目前已知结构的三个鸟类血红蛋白与哺乳类和硬骨鱼类血红蛋白的晶体结构数据进行了比较,发现鸟类、硬骨鱼类和哺乳类血红蛋白具有不同的四级结构特征,鸟类和硬骨鱼类血红蛋白的各亚基间的距离比哺乳类血红蛋白大,其中,α１－β１亚基间的距离为：硬骨鱼类Ｈｂ＞鸟类Ｈｂ＞哺乳类Ｈｂ;α１－β２、α１－α２和β１－β２亚基间的距离以及两个αβ二聚体的距离为：鸟类Ｈｂ＞硬骨鱼类Ｈｂ＞哺乳类Ｈｂ。进一步由一级结构的比较     

Provincial distribution of three HIV-1 resistant polymorphisms (CCR5-Δ32, CCR2-64I, and SDF1-3' A) in China

CCR5-Δ2, CCR2-641, mutants in two chemokine receptors and SDF1-3' A, mutant in a ligand gene, can delay AIDS pathogenesis. The distribution of the three polymorphic loci was studied in 1 046 DNA samples from 26 provinces (cities) in China. No CCR5-Δ32 was observed. CCR2-64I and SDF1-3' A had reverse distribution cline from south to north in China, with average frequency of 20.8% and 24.8% respectively. Relative hazard was evaluated. Important information to the epidemiology of AIDS and the origin and spread of these polymorphic loci in Chinese was provided.     

广东顺德生态乐园夏季鸟类资源和保护

报道了顺德生态乐园夏季鸟类资源的调查 ,记录了该乐园鸟类有 55种 ,隶属 6目2 0科 ,其中属国家二级重点保护鸟类 9种。对鸟类的生态作用、种类和组成作了讨论 ,并提出了保护鸟类的重要性和保护措施。