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61.
目的:探讨应用RNA干扰(RNAi)技术抑制神经元E3B1基因表达及其对轴突生长的影响.方法:选择针对E381(NCBI:NM-024397)RNAi的3个靶位点Abil1、Abil2、Abil3和1个不针对任何mRNA的RNAi靶位点(阴性对照)以及甘油醛-3-磷酸脱氢酶(GAPDH,阳性对照),用带有neoR选择标志和GFP绿色荧光标志的真核表达载体pGenesil-1构建E381 RNAi质粒,分别转染培养的神经元,在荧光显微镜下观测转染率,经G418筛选得到单一的转染细胞,并用Western blot法检测各转染组神经元E3B1蛋白的表达情况,选出具有最佳抑制效应的siRNA转染神经元,加人轴突生长抑制物,观测轴突生长情况.结果:成功构建了RNAi质粒,各组细胞的转染率相近,均为34%左右.与阴性对照组相比,Abil1、Abil2和Abil3转染组细胞内E3B1 mRNA的表达都受到了不同程度的抑制,其中Abil3转染组细胞的E381 mRNA和蛋白的表达抑制最为显著,加入轴突抑制剂后Abil3转染组神经元轴突仍能继续生长.结论:应用RNA干扰技术能高效特异地抑制神经元E3B1基因的表达,E3B1基因的表达下调可促进神经元轴突的生长. 相似文献
62.
M. I. Manrique-Poyato A. J. Muñoz-Pajares V. Loreto M. D. López-León J. Cabrero J. P. M. Camacho 《Chromosome research》2006,14(6):693-700
We have analysed B chromosome frequency for three consecutive years, B transmission rate at population and individual levels,
clutch size, egg fertility and embryo–adult viability in a natural population of the grasshopper Eyprepocnemis plorans containing two different B chromosome variants, i.e. B2 and B24, the second being derived from the first and having replaced it in nearby populations. From 2002 to 2003 the relative frequency
of both variants changed, although the differences did not reach significance. A mother–offspring analysis showed no significant
effect of any of the two B variants on clutch size, egg fertility or embryo–adult viability, but B24 was more efficiently transmitted than B2 through males from the 2002 season, which explains the observed frequency change. Controlled crosses, at individual level,
showed significant drive through some females for B24 but not for B2, suggesting that this difference in transmission rate might also be important for the substitution process. The analysis
of relative fitness for B2 and B24 carriers for all fitness components, as a whole, showed a significantly better performance of B24-carrying individuals, suggesting that the cumulative effect of these slight differences might contribute to the replacement
of B2 by B24.
Electronic Supplementary Material Supplementary material is available for this article at . 相似文献
63.
对我科1989-1990年中收治的婴儿肝炎综合征63例的临床表现、合并症、治疗等方面进行了分析。笔者认为婴儿肝炎综合征为一组临床症候群。病因诊断有其重要性。腹部B超检查有助于肝炎和胆道闭锁的鉴别,可作为常规检查方法。并认为用肾上腺皮质激素治疗有效。 相似文献
64.
硒和/或维生素E预防大鼠内皮细胞损伤的实验研究 总被引:15,自引:1,他引:14
用含硒(Se0.5mg/kg)和/或维生素E(VE0.6g/kg)的高脂饲料喂养成年雄性Wistar大鼠12周。结果:高脂对照组大鼠血浆前列腺素Flα(6-酮-PGF1α)水平下降,而血清脂质过氧化物(LPO)、血浆血栓素(TXB2)及内皮素(ET)水平上升;补Se、VE及Se+VE可明显降低大鼠血清LPO、血浆TXB2、ET及TXB2/6-酮-PGF1α比值。同时,除了明显提高血浆谷胱甘肽过氧化物酶(GSH-Px)活力外,血浆6-酮-PGF1α浓度明显升高。实验提示,Se和/或VE有调节花生四烯酸代谢及保护内皮细胞的作用。 相似文献
65.
对29例慢性乙型肝炎伴肝胆结石患者.采用Elisa和斑点杂交技术检测外周静脉血、胆管胆汁和门静脉血中乙型肝炎两对半及HBV-DNA.并比较HkAg含量.结果,外周静脉血、胆汁和门静脉血中HBsAg浓度分别为;2244.73±59722ng/ml、1181.65±370.91ng/ml、2013.62±483.47ng/ml;HBV-DNA阳性检出率分别为62.07%(18例),72.41%(21例)及68.97%(20例).提示肝细胞内复制的HHV在进入血循环的同时,部分随胆汁的分泌排入肠道,并可能通过受损肠粘膜进入门静脉再回到肝脏,造成HBV对肝脏的重复感染。 相似文献
66.
The effect of Cyclosporin A (CsA) on prostaglandin E2 (PGE2 ) production in human gingival fibroblasts challenged with tumor necrosis factor alpha (TNF-α) was studied. TNF-α (1-100 ng/ml) dose-dependently stimulated PGE2 ; formation in 24 h cultures. CsA (1-100 ng/ml) did not induce PGE2 ; formation itself but potentiated TNF-α induced PGE; formation in gingival fibroblasts in a manner dependent on the concentrations of both CsA and TNF-α. TNF-α (10 ng/ml) stimulated the release of [3 H]-arachidonic acid (A.A) from prelabelled fibroblasts that was potentiated by CsA (100 ng/ml). Addition of exogenous unlabelled AA (5-20 μM/ml) to the cells resulted in enhanced PGE2 : formation that was not potentiated by CsA (100 ng/mi). Furthermore. CsA (100 ng/ml) did not further increase the level of cyclooxygenase-2 mRNA induced by TNF-α (10 ng/ml). although PGE2 formation was enhanced. The results indicate that CsA and TNF-α act in concert on PGE2 formation in gingival fibroblasts. which may be of importance in the pathogenesis of gingival overgrowth induced by the drug. 相似文献
67.
Chronic vitamin E treatment prevents defective endothelium-dependent relaxation in diabetic rat aorta 总被引:2,自引:2,他引:0
Summary We examined the effect in rats of 2 months of streptozotocin-induced diabetes mellitus on relaxation and contraction of aortas in vitro. A further diabetic group was treated from time of diabetes induction with a 1% dietary supplement of vitamin E. Diabetes caused a 26.5% deficit (p<0.001) in maximum endothelium-dependent relaxation to acetylcholine in phenylephrine-precontracted aortas. This was 64.3% attenuated (p<0.01) by vitamin E treatment; maximum relaxation was not significantly altered compared to non-diabetic rats. Vitamin E treatment of non-diabetic rats did not significantly affect acetylcholine-induced relaxation. Diabetes or treatment did not significantly alter acetylcholine sensitivity. Endothelium-independent relaxation response to glyceryl trinitrate was not affected by diabetes or vitamin E treatment, indicating that vascular smooth muscle responses to nitric oxide remained unaltered. There was a 35.4% reduction in the maximum contractile response to phenylephrine with diabetes (p<0.05) which was unaffected by vitamin E treatment. The data suggest that the chronic deficit in nitric oxide-mediated endothelium-dependent relaxation in diabetes depends largely upon excess activity of reactive oxygen species. Treatment with vitamin E to increase free radical scavenging specifically protected vascular endothelium although it had no effect on deficits in vascular smooth muscle contractile responses.Abbreviations NO
Nitric oxide
- ARI
aldose reductase inhibitor
- ACH
acetylcholine
- GTN
glyceryl trinitrate
- GSH
reduced form of glutathione
- EC50
effective concentration for 50% of the maximal response 相似文献
68.
69.
血清Ⅲ型原胶原含量与肝纤维化的关系(附102例肝活检分析) 总被引:1,自引:0,他引:1
为进一步研究血清Ⅲ型原胶原(PCⅢ)含量与肝纤维化的关系,对肝炎患者血清PCⅢ含量与肝炎组织学变化进行对比分析.方法:用RIA法测定616例急、慢性肝炎及肝硬化患者的血清PCⅢ含量,其中102例同时做肝活检,按照Knodell肝组织炎症活动性指数标准记分.结果:急、慢性肝炎及肝硬化患者血清PCⅢ含量明显高于正常人,差异有显著性(P<o.05~0.01).其升高的血清PCⅢ含量与肝细胞坏死范围及门管区炎症程度无相关性(r=0.494,P>0.05),而与肝纤维化程度呈正相关(r=0.668,P<0.01).结论:血清PCⅢ测定是判断慢性肝炎及肝硬化时肝纤维化程度的有用指标. 相似文献
70.
Kurt H. Chau George J. Dawson Khalif M. Bile Lars O. Magnius Maria H. Sjogren Isa K. Mushahwar 《Journal of medical virology》1993,40(4):334-338
A newly developed assay for IgA class antibody to hepatitis E virus (IgA anti-HEV) was used to study 145 serum samples collected during an outbreak of an enterically transmitted hepatitis that occurred in 3 villages in the lower Shebeli region of Southern Somalia between January, 1988 and November, 1989. A total of 52.4% of the afflicted patients were found positive for IgA anti-HEV, and 73.1% of these were also positive for IgM. Both antibodies disappeared during the convalescence period. Similar results were also seen in serum obtained from sporadic cases of acute waterborne hepatitis in Pakistan. © 1993 Wiley-Liss, Inc. 相似文献