汉族人载脂蛋白B基因EcoRⅠMspⅠ多态性与冠心病的关系研究

目的 探讨我国北方地区汉族人载脂蛋白B(apoB)基因EcoRⅠ、MspⅠ多态性与冠心病的关系。方法 应用聚合酶链反应限制性片段长度多态性(PCR—RFLP)技术，检测了120名对照组和137例冠心病组apoB基因EcoRⅠ、MspⅠ多态性基因型和等位基因频率分布。研究了apoB基因多态性对血脂、脂蛋白和载脂蛋白水平的影响。结果 冠心病组与对照组apoB基因EcoRⅠ、MspⅠ多态性基因型和等位基因频率分布差异无显著性，且与性别、家族史、吸烟史、体重指数及冠脉病变程度无明显关系。两组间罕见的E—和M—等位基因存在连锁不平衡。冠心病组中E—等位基因携带者血清血清总胆固醉(TC)、低密度脂蛋白(LDL-C)明显高于仅含E 等位基因者。M—等位基因与各项血脂水平无明显相关性。结论 apoB基因EcoRⅠ、MspⅠ多态性对人群血脂水平有一定影响，但不是我国北方地区汉族人冠心病发生的独立危险因素。     

Biochemical and histological changes in pulmonary fibrosis induced in rabbits with intratracheal bleomycin

Pulmonary fibrosis was induced in rabbits by an intratracheal instillation of bleomycin. Histologically, at 2 weeks there was inflammation but only limited evidence of increased collagen deposition; at 8 weeks the inflammatory response had subsided and increased collagen deposition, characteristic of early interstitial fibrosis, was observed. Biochemical analyses showed bleomycin treatment caused marked increases in the total amounts of RNA, DNA, mixed protein, collagen and elastin when compared to controls (P less than 0.001 in all cases). Furthermore the increases were essentially complete by 2 weeks where the contents had increased by 110 +/- 13%, 60 +/- 11%, 148 +/- 12%, 94 +/- 15% and 89 +/- 11% respectively (P less than 0.001 in all cases). When collagen and elastin were expressed as concentrations with respect to wet weight, total protein or DNA content, the changes were not statistically significant. No changes were observed in the relative amounts of type I and type III collagen. It is concluded that: (1) compared to biochemical analysis, histology is relatively insensitive in detecting the early increases in connective tissue proteins; (2) measurements of lung collagen and elastin should be expressed as total lung contents wherever possible; the concentration of these proteins may remain unchanged, especially in the early stages of fibrosis, due to concomitant increases in other lung constituents; (3) changes in the relative amounts to types I and III collagens do not play a major role in the pathology of this form of pulmonary fibrosis.     

Gene profiling of maternal hepatic adaptations to pregnancy

Background: Maternal metabolic demands change dramatically during the course of gestation and must be co‐ordinated with the needs of the developing placenta and fetus. The liver is critically involved in metabolism and other important functions. However, maternal hepatic adjustments to pregnancy are poorly understood. Aim: The aim of the study was to evaluate the influences of pregnancy on the maternal liver growth and gene expression profile. Methods: Holtzman Sprague–Dawley rats were mated and sacrificed at various stages of gestation and post‐partum. The maternal livers were analysed in gravimetric response, DNA content by PicoGreen dsDNA quantitation reagent, hepatocyte ploidy by flow cytometry and hepatocyte proliferation by ki‐67 immunostaining. Gene expression profiling of non‐pregnant and gestation d18.5 maternal hepatic tissue was analysed using a DNA microarray approach and partially verified by northern blot or quantitative real‐time PCR analysis. Results: During pregnancy, the liver exhibited approximately an 80% increase in size, proportional to the increase in body weight of the pregnant animals. The pregnancy‐induced hepatomegaly was a physiological event of liver growth manifested by increases in maternal hepatic DNA content and hepatocyte proliferation. Pregnancy did not affect hepatocyte polyploidization. Pregnancy‐dependent changes in hepatic expression were noted for a number of genes, including those associated with cell proliferation, cytokine signalling, liver regeneration and metabolism. Conclusions: The metabolic demands of pregnancy cause marked adjustments in maternal liver physiology. Central to these adjustments are an expansion in hepatic capacity and changes in hepatic gene expression. Our findings provide insights into pregnancy‐dependent hepatic adaptations.     

Renca 条件培养基转化的调节性T细胞 对小鼠同种免疫的影响

 【目的】 探讨小鼠肾癌细胞株Renca来源的条件培养基能否诱导CD4+ CD25- T细胞转化为具有免疫抑制效能的CD4+ CD25+ Foxp3+ T细胞&#65377; 【方法】 培养Renca提取上清获得条件培养基,将条件培养基与普通培养液按不同比例混合培养小鼠CD4+ CD25- T细胞7 d,以流式细胞仪检测CD4+ CD25+ T细胞和Foxp3+ 细胞的比例;再次分选CD4+ CD25+ T细胞检测其抑制细胞增殖的能力,体内过继性输入观察对移植物存活时间&#65380;局部排斥反应和迟发性超敏反应的影响&#65377;【结果】 与对照组相比,混合培养基显著增加培养体系中CD4+ CD25+ Foxp3+ T细胞的比例(P < 0.05),在一定范围内(≤75%)呈比例依赖关系;随转化性CD4+ CD25+ T细胞比例增加效应T细胞增殖能力减弱;体内输注显著延长移植物的存活时间(P < 0.05),达(29.6 ± 1.4) d,组织学观察显示能明显抑制局部排斥反应&#65377;【结论】 Renca条件培养基能诱导CD4+ CD25- 细胞转化为 CD4+ CD25+ Foxp3+ T细胞,被转化细胞在体内和体外均能发挥免疫抑制作用&#65377;     

Short peptide nucleic acids (PNA) inhibit hepatitis C virus internal ribosome entry site (IRES) dependent translation in vitro

The internal ribosome entry site (IRES) of hepatitis C virus (HCV) which governs the initiation of protein synthesis from viral RNA represents an ideal target for antisense approaches. Using an original bicistronic plasmid, we first established that sequence and translational activity of HCV IRESs cloned from six patients, whether responders or not to combination therapy, were conserved. We then tested the hypothesis that antisense molecules, i.e. short peptide nucleic acids (PNA), could inhibit HCV translation by binding to the highly conserved IIId or IV loop regions of the IRES. Five 6–10 mer PNAs were designed. They strongly inhibit HCV IRES-driven translation in a rabbit reticulocyte lysate assay. This inhibition was highly specific since corresponding PNAs with only one mismatch were inactive. Short phosphorothioate oligonucleotides of same sequence were unable to inhibit HCV translation. PNA molecule was shown to have anti-HCV activity in Huh-7.5 cells when electroporated with a full-length HCV genome construct. Using oligonucleotide as carrier, PNA was also transfected in HCV replicon-harboring cells and in JFH1 infected Huh-7.5 cells.