GRIM-19基因对前列腺癌DU145细胞的促凋亡作用

目的探讨GRIM-19基因对前列腺癌DU145细胞的促凋亡作用，并分析相关机制．方法将构建成功的pGRIM-19重组质粒转染DU145细胞株，应用MTT法检测其对细胞增殖能力的影响，通过流式细胞术检测细胞周期及凋亡率，应用半定量RT-PCR检测GRIM-19及caspase-3 mRNA转录水平．结果流式细胞术结果显示：与对照组比较，pGRIM-19重组质粒明显抑制DU145细胞增殖，并使细胞周期发生改变，多数细胞抑制在G0／G1期，细胞凋亡率增加明显；通过RT—PCR电泳结果证实：pGRIM-19重组质粒明显促进GRIM-19的表达，同时激活caspase-3．结论重组质粒pGRIM-19可明显抑制DU145细胞增殖，并促进其凋亡，其凋亡的发生机制与激活caspase-3有关．

In Vitro Antioxidant and Radio Protective Activities of Lycopene from Tomato Extract against Radiation—Induced DNA Aberration

Background: The accumulation of free radicals is linked to a number of diseases. Free radicals can be scavenged by antioxidants and reduce their harmful effects. It is therefore essential to look for naturally occurring antioxidants that come from plants, as synthetic antioxidants are toxic, carcinogenic and problematic for the environment. Lycopene is one of the carotenoids, a pigment that dissolves in fat and has antioxidant properties. Materials and Methods: The antioxidant and free radical scavenging activity were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The impact of lycopene on bacteria (E. coli) susceptibility to γ-radiation was examined by radio sensitivity assay. The study also examined the induction of strand breaks in plasmid pUC19 DNA and how lycopene extract protected the DNA from γ-radiation in vitro. Results: At varying concentrations, lycopene demonstrated its ability to scavenge free radicals such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH). IC50 for lycopene was determined at 112 μg/mL which was almost partial to IC50 of standard antioxidant L-ascorbic acid. The D10 value 180 Gy of E. coli was found to be >2-fold higher in the extract-containing lycopene sample than in the extract-free controls. The lycopene extracts inhibited the radiation-induced deterioration of the plasmid pUC19 DNA. At an IC50 concentration, lycopene provided the highest level of protection. Conclusion: Lycopene functions as an efficient free radical scavenger and possible natural antioxidant source. For cancer patients and others who frequently expose themselves to radiation, lycopene may be a useful plant-based pharmaceutical product for treating a variety of diseases caused by free radicals.

空肠弯曲菌Penner O:19 galE基因真核表达质粒的构建

目的构建空肠弯曲菌Penner O:19 galE基因真核表达质粒。方法 PCR扩增空肠弯曲菌Penner O:19 galE基因,构建pGEM-T-galE克隆质粒及构建pEGFP-N1-galE真核表达质粒,并检测真核表达质粒在293T细胞中的表达。结果构建了真核表达质粒pEGFP-N1-galE,检测到其在293T细胞表达。结论 pEGFP-N1可作为Penner O:19 galE基因的真核表达载体。

活体内细菌移位示踪方法的研究

目的为解决内源性感染细菌体内示踪问题，本实验采用ＰＵＣ１９质粒载体示踪加限制性内切酶酶切图谱分析法和荧光标记示踪法，对肠道移位细菌进行了动态观察。并对两种方法进行了比较。方法依据ＰＵＣ１９质粒特点设计了动物模型，１１０只Ｗｉｓａｒ大鼠致成３０％体表面积Ⅲ°烫伤，于６、１２、２４、４８ｈ和１２天分别活杀，做荧光显微镜检查和细菌培养，质粒提取和酶切。结果烧伤后肠道细菌可移位至淋巴结和肝脏，荧光标记方法细菌到达淋巴结（９５％）和肝脏（５７．５％）的百分率略高于ＰＵＣ１９示踪方法（７８．４％、５２．４％）。结论用ＰＵＣ１９质粒载体做示踪物可减少非特异性因素。

钩端螺旋体重组DNA探针对致病性黄疸出血群钩体DNA的杂交识别

作者从建立的黄疸出血群钩端螺旋体(下称钩体)DNA基因库中筛选出重组DNA克隆PLIps01(15kb)和PLIEc34(4kb)制备成^(32)P放射性探针。以该二探针对致病性黄疸出血群所属血清型的13个菌株钩体DNA进行Southern印迹分析,结果表明,该二DNA探什对黄疸出血群各株钩体DNA具有强烈的特异性结合,能识别出简洁的DNA带型,并能区分不同血清型以至菌株的DNA带型差别。作者认为,钩体DNA重组探什结合Southern印迹分析是一种灵敏而特异的检测分析方法,可作为诊断、鉴定和分析钩体的工具。

Tracing method study of bacterial translocation in vivo

INTRODUCTIONEndogenesis infection plays an important role innosocomial infection.By studying progress ofbacteria translocation from intestinal tract,theconcept of gut-origin infection has been acceptedgradually.Because of no ideal tracing method,there were some controversies.In order to solve theproblem,the PUC19 plasmid vector tracing

人微小病毒3个主要蛋白基因真核表达载体的构建

目的:分别克隆人细小病毒B19三个主要蛋白VP1、VP2、NS1全长基因,构建真核表达载体。方法:利用PCR和分子克隆技术,分别将B19病毒vp1、vp2、ns1基因全长片段扩增后,构建带荧光标签的真核表达载体;在人体细胞中表达并通过荧光、RT-PCR和Western Blot、测序等方法鉴定。结果:成功构建了包含B19病毒vp1、vp2、ns1全长基因,并在人体细胞中表达了VP1、VP2、NS1蛋白。结论:人微小病毒B19三个主要蛋白基因得到克隆和表达,为进行相关的研究奠定了基础。