运动训练联合基因治疗对肾性高血压大鼠肾功能的影响

目的观察运动训练联合β1肾上腺素能受体基因治疗对肾性高血压大鼠血压、肾功能、肾脏前肾素原mRNA、肾脏β1受体mRNA和蛋白的影响，探讨其改善肾功能的机制。方法两肾一夹法制作肾性高血压模型，基因治疗采用经鼠尾静脉注射阳离子脂质体与β1反义寡核苷酸方法。检测大鼠血压、肾功能变化。半定量RT—PCR测定肾脏β1受体mRNA、前肾素原mRNA水平。Western印迹法测检肾脏β1受体的蛋白水平。结果与模型组比较，运动联合基因治疗可使血压下降并维持4周，血压下降最高达41mmHg；尿蛋白量[（45．82±6．56）比（29．12±5．22）mg／L，P〈0．01】、BUN[（13．10±2．62）比（9．05±1．84）mmol／L，P〈0．05]显著降低（P〈0．01，P〈0．05）；内生肌酐清除率显著升高（P〈0．01）；前肾素原mRNA、β1受体mRNA、蛋白表达水平显著降低（P〈0．05）。结论运动训练联合β1受体反义基因治疗可以明显地降低血压，改善肾功能；且运动训练可以增强基因治疗对β1受体mRNA和蛋白的抑制作用，在转录和翻译水平抑制过度激活的β1受体的表达。     

转化生长因子β1短发夹RNA对白蛋白刺激人肾近曲小管上皮细胞细胞因子表达的影响

目的 研究pcDU6载体质粒介导的转化生长因子β1（TGF-β1）短发夹RNA（shRNA）对人血清白蛋白（HSA）致人肾近曲小管上皮细胞（HK2细胞）增殖，TGF-β1、结缔组织生长因子（CTGF）和纤连蛋白（FN）表达的影响，并探讨有关机制。方法 构建TGF-β1shRNA的pcDU6载体质粒，体外培养HK2细胞株。采用脂质体转染将表达TGF-β1shRNA的pcDU6质粒载体（pcDU6-A1-A2和peDU6-B1-B2）分别导人实验组细胞。用HSA（5g／L）刺激HK2细胞12h或24h。四甲基偶氮唑盐（MTF）比色法测定细胞增殖水平。RT-PCR半定量分析HK2细胞中TGF-β1、CTGF和FNmRNA的表达水平；双抗夹心酶联免疫吸附法检测HK2细胞培养液中TGF-β1及FN蛋白质水平。结果 HK2细胞在HSA刺激下，其TGF-β1、CTGF及FNmRNA的表达明显上调，培养液中TGF-β1和FN的蛋白质含量亦明显升高（P〈0．05）。与pcDU6空载体组比较，pcDU6载体质粒介导的TGF-β1shRNA干扰组TGF-β1、CTGF及FNmRNA的表达明显下调（P〈0．05）。TGF-β1shRNA转染HK2细胞后12h或24h，细胞培养液中TGF-β1和FN蛋白质含量明显下降，HK2细胞增殖被部分抑制（P〈0．05）。在细胞增殖、TGF-β1、CTGF及FN基因表达方面，TGF-β1shRNA干扰组组间比较，以及pcDU6空载体转染组与HSA刺激组比较，差异均无统计学意义。结论 peDU6载体质粒介导的TGF-β1shRNA能够明显抑制HSA刺激下HK2细胞增殖、TGF-β1、CTGF和FN基因的表达。HSA刺激HK2细胞增殖及CTGF和FN基因的过表达可能通过TGF-β1介导。     

RGD-based strategies for selective delivery of therapeutics and imaging agents to the tumour vasculature

During the past decade, RGD-peptides have become a popular tool for the targeting of drugs and imaging agents to alphavbeta3-integrin expressing tumour vasculature. RGD-peptides have been introduced by recombinant means into therapeutic proteins and viruses. Chemical means have been applied to couple RGD-peptides and RGD-mimetics to liposomes, polymers, peptides, small molecule drugs and radiotracers. Some of these products show impressive results in preclinical animal models and a RGD targeted radiotracer has already successfully been tested in humans for the visualization of alphavbeta3-integrin, which demonstrates the feasibility of this approach. This review will summarize the structural requirements for RGD-peptides and RGD-mimetics as ligands for alphavbeta3. We will show how they have been introduced in the various types of constructs by chemical and recombinant techniques. The importance of multivalent RGD-constructs for high affinity binding and internalization will be highlighted. Furthermore the in vitro and in vivo efficacy of RGD-targeted therapeutics and diagnostics reported in recent years will be reviewed.     

Utilization of recombinant activated factor VII in southern Ontario in 85 patients with and without haemophilia

Recombinant activated factor VII (rFVIIa) is licensed for the treatment of bleeding in individuals with haemophilia and inhibitors. The use of rFVIIa appears to be increasing, and an increase in unlicensed use is suspected. There are currently few data about the specific indications for its use. The aim of this study was to describe the patterns of utilization of rFVIIa. We performed a retrospective cohort study using rFVIIa infusion data collected prospectively and clinical data collected retrospectively. Patients were identified using a tracking system designed to account for use of all coagulation factor concentrates issued in southern Ontario. Between 1 January 2001 and 31 December 2005, 85 patients received rFVIIa. 1164 infusions were given (8246.4 mg). Haemophilia patients with inhibitors accounted for 82.9% of rFVIIa infused and represented 8.2% of patients. The total amount of rFVIIa used increased each year from 2001 to 2004 and then decreased in 2005. The total number of infusions of rFVIIa administered annually increased. Both on-label and off-label use of rFVIIa increased. The number of patients with haemophilia receiving rFVIIa remained small and constant. The number of patients receiving rFVIIa for off-label indications increased markedly. Most rFVIIa infusions were given for licensed indications; however, these infusions represented <10% of patients treated. Overall, the utilization of rFVIIa is increasing, mostly for approved indications; however, the number of patients being prescribed rFVIIa for off-label indications has increased. The tracking system used in this study is a valuable tool to describe ongoing utilization patterns of rFVIIa.     

肝干细胞的基因治疗在肝病中的应用

1.肝干细胞是基因治疗的良好靶细胞:肝干细胞不同于其他的人体肝细胞,有两方面的特征,即具有干细胞的高度增殖的能力,又具有向肝细胞和胆管细胞双向分化的潜能。研究表明完全分化成熟的肝细胞移植入合适的宿主之后可以在肝脏中重新分群发挥功能。为什么要选择肝干细胞作为基因治疗的靶细胞呢?(1)成熟的肝细胞在肝脏中重新分群需要持续的肝损伤或内源性肝细胞增生障碍来提供选择压力,而干细胞则不需要。(2)尽管成熟的肝细胞可以在体外     

脊髓损伤后热休克蛋白27、表皮脂肪酸结合蛋白和金属蛋白酶组织抑制因子-1的基因表达及甲基强的松龙对其表达的影响

目的研究脊髓损伤后热休克蛋白27(HSP27)、表皮脂肪酸结合蛋白(FABPs)和金属蛋白酶组织抑制因子-1(TIMP-1)的基因表达及甲基强的松龙(MP)对其表达的影响.方法SD大鼠30只.随机分为假手术组、单纯脊髓损伤组(损伤组)及脊髓损伤+大剂量MP治疗组(MP组),每组10只.应用改良的Allen's打击法致T8脊髓损伤.MP组大鼠伤后即刻从尾静脉内注射大剂量MP(30mg/kg).损伤后24h切取损伤平面上下0.5cm的脊髓组织,进行RT-PCR反应,检测HSP27、FABPs和TIMP-1的基因表达.结果术后24h假手术组HSP27、FABPs和TIMP-1的基因表达相对丰度分别为0.0643±0.0152、0.6413±0.1005和0.7091±0.0577;损伤组上述三个因子的表达升高,分别为1.0013±0.3861、1.2187±0.2851和0.8971±0.1092,与假手术组比较差异有显著性(P＜0.01、P＜0.05、P＜0.05);MP组上述三个因子的表达继续升高,分别为1.2858±0.1384、1.7122±0.1766和1.2081±0.1093,与损伤组比较差异有显著性(P＜0.05、P＜0.01和P＜0.01).结论脊髓损伤后,邻近损伤处的脊髓组织中HSP27、FABPs及TIMP-1的基因表达显著增高,大剂量MP能进一步促进三个因子表达,发挥组织保护作用.     

Effect of cystathionine beta-synthase variant 844ins68bp and methylenetetrahydrofolate reductase A1298C polymorphisms in xenografts on 5-FU efficacy and doubling time

The association of MTHFR and CBS variants with the doubling time and responsiveness to several chemodrugs was analyzed in 26 human cancer xenografts. The tumors homozygous for the absence of insertion (NN) for the CBS 844ins68bp were more chemosensitive than those with insertion (NI) to TS-1 (P=0.0048), suggesting a potential effect of this variant on fluoropyrimidine efficacy. Furthermore, the doubling time of tumors with a variant C allele (AC or CC) in MTHFR-A1298C was significantly longer than that of tumors with a normal allele (AA) (P=0.0008). Twenty-nine cellular proliferation-related genes were associated with MTHFR-A1298C genotyping and with the doubling time.     

RNA干扰及其在胶质瘤基因治疗中的应用

RNA干扰（RNA interference。RNAi）是双链RNA（double—stranded RNA，dsRNA）降解特异性靶基因转录出的mRNA。从而抑制靶蛋白表达的现象。自从二十世纪九十年代发现RNAi这一现象以来，RNAi已被广泛应用于研究基因功能、信号转导通路和基因治疗等方面。随着分子生物学、分子遗传学等学科的发展．发现了许多与肿瘤发生、发展和预后密切相关的基因。经过大量临床前期试验表明，针对特异性靶基因的小干扰RNA（short／small interfering RNA．siRNA）治疗胶质瘤是行之有效的。为基因治疗胶质瘤提供了新的思路。[第一段]     

失血性休克大鼠肠上皮细胞线粒体DNA腺苷三磷酸酶6,8基因表达及线粒体功能的改变

目的　探讨失血性休克大鼠肠上皮细胞线粒体DNAATPase 6 ,8基因表达及线粒体功能的改变 ,为阐述休克肠道靶学说和线粒体能量代谢提供分子生物学基础。　方法　 2 4只Wistar大鼠随机分为休克前组和休克 1,2 ,3,4 ,5h组。采用RT -PCR方法观察线粒体ATPase 6 ,8mRNA量的改变。用透射电镜观察、生物体视学测量线粒体形态 ,用Clark氧电极测线粒体呼吸功能。　结果　失血性休克 1,2h ,ATPase 6 ,8基因表达增强 ,以后渐减弱 ,至休克 5h表达最低 ,ATPase 6 ,8基因表达分别降为正常的 6 9.3%和 78.4 % (P <0 .0 1和P <0 .0 5 )。失血性休克 2h和5h ,线粒体平均截面积、长径、面密度、体密度均显著增加 (P <0 .0 1) ,休克 5h时分别为休克前的2 .0 ,1.4 5 ,1.4 7,2 .2 2倍。休克 5h ,线粒体比表面和数密度分别下降 32 %和 2 4 % (P <0 .0 1和P <0 .0 5 ) ,嵴和基质破坏明显。失血性休克后肠上皮细胞线粒体呼吸控制率和氧化磷酸化效率比休克前显著降低 (P <0 .0 1)。　结论　失血性休克时大鼠肠上皮细胞线粒体DNAATPase 6 ,8基因表达下调 ,线粒体呼吸功能出现障碍 ,线粒体超微结构发生了改变