Enhancement of glioma cell apoptosis induced by anti-human DR5/DR4 monoclonal antibodies by sub-toxic dose of doxorubicin in human

目的探讨亚毒性剂量的阿霉素影响抗DR4、DR5单克隆抗体(mAb)FMU1.4和FMU1.5诱导3株神经胶质瘤细胞株U343(TRAIL敏感株)、U138(TRAIL部分敏感株)及U373(TRAIL耐受株)凋亡的作用及可能的机制。方法采用流式细胞术检测DR4、DR5的表达及神经胶质瘤细胞中DNA倍增。用MTT比色法检测mAbFMU1.4和FMU1.5对3株神经胶质瘤细胞增殖的抑制作用。用共聚焦显微镜观察3株细胞中Ca2+的浓度。以Westernblot检测细胞内色素C、FLIP[FLICE-inhibitoryprotein,为一组含有死亡效应结构域(DED)的胞浆蛋白]的表达。结果亚毒性剂量的阿霉素作用后,DR5、DR4在3株细胞中的表达提高;而mAbFMU1.4、FMU1.5诱导U138和U373细胞凋亡的作用增强,细胞内细胞色素C的表达提高,FLIP的表达降低,Ca2+浓度增加。结论亚毒性剂量的阿霉素与抗DR4、DR5mAb联合应用后,可提高mAb诱导靶细胞凋亡的效应,其作用机制与DR4、DR5、细胞色素C、FLIP的表达及Ca2+的含量有关。 【英文摘要】 AIM: To study the cytotoxic effects of doxorubicin on apoptosis in glioma cell lines U343, U138, U373 induced by anti-human DR4/DR5 monoclonal antibodies (FMU1.4/FMU1.5) and the underlying mechanism. METHODS: Expression of DR4/DR5 was quantitated by flow cytometry. Cytotoxicity exerted by FMU1.4/FMU1.5 on three cell lines was measured by MTT colorimetry and the induced apoptosis was determined by agarose gel electrophoresis. The expression of cytochrome C, FLIP and Ca 2+ concentration were also measured. RE...教育部跨世纪优秀人才培养计划资助项目(2000年

Characteristic of Soil Nutrient in Dam System and Its Relation with Erosion Environment in the Loess Hilly Region Ⅱ. Particles Distribution and Its Nutrient Condition in Dam System Soil

坝系土壤粒径均以粉粒为主，含量占土壤的６６％～７０％。各土壤间粉粒含量差异很小，所不同的是，坝地富粘层粗粉粒少细粉粒多，砂粒少粘粒多，坝、坡轻壤层反之。土壤ＯＭ、ＴＮ主要集中在粘粒中，其浓度在粗细颗粒中差别悬殊。ＴＰ及ＴＫ在粗细颗粒中这种差别就较小。土壤中各形态锌均随着土壤颗粒变细而浓度增加，在＜０．００５ｍｍ粒径中浓度陡然提高。故坝地富粘层中ＯＭ、ＴＮ、ＡＺｎ的含量最丰。上述粒径及养分分布特点，揭示了在泥沙迁移淤积过程中，坝地不同部位土壤养分差异的内在原因

Characteristic of Soil Nutrients in Dam System and Its Relation with Erosive Environment in the Loess Hilly Region Ⅰ.The Physicochemical Properties and Numerical Analysis of Dam System Soil

坝地土壤有明显的层次构型，上轻下粘，存在着相当于作物养分库的富粘层，对耕作和保蓄水肥十分有利。土壤养分贮量随粘粒的增加而提高。坡地土壤无明显层次，养分贮量远低于坝地的中粘层与富粘层，故坝、坡地上层养分差异不大，３０ｃｍ以下坝地远高于坡地。坝地土壤肥力形成以粘粒化过程为主，养分间协调性较好，坡地土壤以有机质积累过程为主，养分相对处于离散状态。坝地粘粒富集层锌的供应容量与强度均较大，生长的黑麦草干物质与养分累积量较多

杆状病毒表达EV71病毒样颗粒的装配、制备纯化与鉴定

将EV71P1和3CD基因片段克隆入同一杆状病毒穿梭质粒Bacmid中,构建出重组杆状病毒表达质粒Bac-mid-P1-3CD;脂质体介导其转染Sf9昆虫细胞获得共表达P1和3CD的重组杆状病毒(AcMNPV-P1-3CD)。用IFA和Western-blot法对表达产物进行鉴定和分析。电镜结果显示P1经3CD切割装配成了大小约为27nm的类球形颗粒(即EV71VLPs)。进一步分析影响杆状病毒表达系统的因素以对表达条件进行优化,结果显示MOI值和时间均可影响目的蛋白的表达,其中时间是主要因素。选择优化后条件利用无血清培养基对贴壁Sf9细胞在多层细胞培养器中进行VLPs的大量表达,密度梯度离心法纯化,SDS-PAGE结果可见三条大小约为39kD、34kD和26kD的VP1、VP0和VP3特异性条带。纯化后EV71VLPs颗粒结构完好,为下一步EV71蛋白结构的基础研究和基因工程疫苗的研究奠定了基础