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111.
Endothelial inflammation with chemokine involvement contributes to acute coronary syndromes (ACS). We tested the hypothesis that variation in the chemokine gene CXCL5, which encodes epithelial neutrophil-activating peptide (ENA-78), is associated with ACS prognosis. We also investigated whether statin use, a potent modulator of inflammation, modifies CXCL5's association with outcomes and characterized the in vitro effect of atorvastatin on endothelial ENA-78 production. Using a prospective cohort of ACS patients (n = 704) the association of the CXCL5 -156 G>C polymorphism (rs352046) with 3-year all-cause mortality was estimated with hazard ratios (HR). Models were stratified by genotype and race. To characterize the influence of statins on this association, a statin*genotype interaction was tested. To validate ENA-78 as a statin target in inflammation typical of ACS, endothelial cells (HUVECs) were treated with IL-1beta and atorvastatin with subsequent quantification of CXCL5 expression and ENA-78 protein concentrations. C/C genotype was associated with a 2.7-fold increase in 3-year all-cause mortality compared to G/G+G/C (95%CI 1.19-5.87; p = 0.017). Statins significantly reduced mortality in G/G individuals only (58% relative risk reduction; p = 0.0009). In HUVECs, atorvastatin dose-dependently decreased IL-1beta-stimulated ENA-78 concentrations (p<0.0001). Drug effects persisted over 48 hours (p<0.01). CXCL5 genotype is associated with outcomes after ACS with potential statin modification of this effect. Atorvastatin lowered endothelial ENA-78 production during inflammation typical of ACS. These findings implicate CXCL5/ENA-78 in ACS and the statin response.  相似文献   
112.
OBJECTIVE: Function of the renin-angiotensin system is important to human hypertension, but its genetic etiology remains elusive. We set out to examine a hypothesis that multiple genetic variants in the system act together in blood pressure regulation, via intermediate phenotypes such as blood pressure reactivity. METHODS: A sample of 531 hypertensive cases and 417 controls was selected from the HyperGEN study. Hypertension-related traits including blood pressure responses to challenges to math test, handgrip and postural change (mathBP, gripBP, and postBP), and body mass index (BMI) were analyzed for association with 10 single nucleotide polymorphisms (SNPs) in the angiotensinogen (AGT) gene. Single-marker and haplotype analyses were performed to examine the effects of both individual and multiple variants. Multiple-trait profiling was used to assess interaction of latent intermediate factors with susceptible haplotypes. RESULTS: In Blacks, two SNPs in exon 5 and 3'UTR showed significant association with gripBP, and two promoter SNPs were strongly associated with postBP. In Whites, only borderline association was found for 2 promoter SNPs with mathBP. Haplotype analyses in Blacks confirmed association with gripBP, and detected significant association of a haplotype to BMI (p=0.029). With the interactions modeled, haplotype associations found in Blacks remain significant, while significant associations to BMI (p=0.009) and gripSBP emerged in Whites. CONCLUSION: Genetic variants in regulatory regions of AGT showed strong association with blood pressure reactivity. Interaction of promoter and genic SNPs in AGT revealed collective action of multiple variants on blood pressure reactivity and BMI both in Blacks and in Whites, possibly following different pathways.  相似文献   
113.
白首乌化学成分与药理活性研究进展   总被引:14,自引:0,他引:14  
白首乌类植物含有C21甾体酯甙类、磷脂类、苯乙酮甙类等化学成分,具有抗氧化、调节免疫功能、抗肿瘤、抗缺氧、降血脂等多种药理活性.主要综述了近年来白首乌类植物化学成分及药理活性研究进展概况.  相似文献   
114.
抗盐耐海水植物的种植是有效利用和开发滩涂资源的措施之一。采用温室砂培方式, 研究了不同稀释配比的海水处理8天对苦荬菜(Lactuca indica)幼苗生物量、根冠比、叶绿素含量、离子含量、可溶性蛋白和可溶性糖含量的影响。结果表明: 苦荬菜幼苗地上部受海水胁迫较为显著, 而根在海水浓度小于30%时与对照相比没有显著差异; 根冠比随着海水浓度的增加而不断提高; 在10%和20%海水浓度处理下, 叶绿素含量与对照相比差异不显著, 但随着海水浓度的进一步增加,叶绿素含量显著下降; 在10%海水浓度处理下, 苦荬菜地上部分及根部的K+含量与对照相比差异不显著, 而海水浓度高于10%时, 随着海水浓度的增加地上部和根部的K+含量均逐渐降低; 海水处理下, 苦荬菜体内Na+和Cl–含量逐渐增加; 地上部可溶性糖含量逐渐增加, 而可溶性蛋白含量先升后降。海水胁迫下, 苦荬菜幼苗维持一定的K+选择性吸收是其一定程度上盐适应的重要原因。同时, 积累的可溶性糖和可溶性蛋白是苦荬菜幼苗在盐胁迫下的重要渗透调节物质, 可作为其抗盐性的生理参数。  相似文献   
115.
P-LISA技术     
原位邻近式连接分析(proximity ligation in situ assay,P-LISA)是一种用来研究蛋白质-蛋白质相互作用的新方法。该方法能够对原位、瞬时、微弱的蛋白质-蛋白质相互作用进行定量分析和亚细胞定位,在药物研发和临床诊断中将有着重要的应用价值。  相似文献   
116.
Objective: Considering that waist‐to‐hip ratio (WHR) is a simple anthropometric measure of obesity and is a better predictor of coronary heart disease than body mass index (BMI), the genetic underpinnings of WHR are of interest. The inheritance pattern of WHR, before and after adjustment for BMI (WHR‐BMI), was investigated in 2713 individuals from 1038 nuclear families in the National Heart, Lung, and Blood Institute Family Heart Study (NHLBI‐FHS). Research Methods and Procedures: Waist and hip measurements were taken twice, and the means of the measurements were used to calculate the WHR. Adjustments for age were carried out separately by sex, using stepwise multiple regression procedures for WHR and WHR‐BMI phenotypes. Segregation analysis was applied using the unified model as implemented in the computer program POINTER. Results: For age‐adjusted WHR, the segregation results suggested an additive major gene that accounts for 35% of the phenotypic variance, and approximately 30% of the sample are homozygous for the “high” genotype. The results for age‐ and BMI‐adjusted WHR were also compatible with a major gene; however, the multifactorial model provided the most parsimonious fit to the data. Discussion: Although the genetic mechanisms for several obesity traits have been studied, tests of Mendelian segregation on this simple anthropometric measure (WHR) have not been reported previously. This study provides evidence for the presence of a major gene for age‐adjusted WHR, suggesting that it is an appropriate trait for further genetic analysis, especially because it has strong predictive value and probably relates biologically to cardiovascular risk.  相似文献   
117.
辽宁本溪小碑洞和周口店第一地点发现的狼獾属 (Gulo) 化石,分属于真狼獾 Gulo gulo (Linnaeus, 1758) 和施氏狼獾 Gulo schlosseri Kormos, 1924.前者为环北极分布的寒冷型动物,后者为中纬度分布的温暖型动物;据裂齿形态分析, G. gulo 比 G. schlosseri 具更强的肉食性; G. gulo 从中更新世首次出现至今,体型经小(中更新世)—大(晚更新世)—小(现代)的变化过程,性双形现象日趋消失; G. schlosseri 仅见于更新世,体型变化不大.利用分支分析方法,本文认为: Plesiogulo 和 Gulo; G. schlosseri 与 G. gulo 应分别属于姐妹属和姐妹种关系,而非承继关系.  相似文献   
118.
本文介绍用脆弱类杆菌抗血清标记SpA(Bf—SpA)做协同凝集试验(CoA)调查123例正常分娩后妇女宫颈处的脆弱类杆菌,阳性率为22.7%,与常规厌氧培养法相比,SpA协同凝集试验具有特异性强、敏感性高、方法简便、快速的优点,适宜在基层单位推广应用。  相似文献   
119.
桔小实蝇在中国云南省的分布(英文)   总被引:9,自引:0,他引:9  
在云南 1 2个县的诱捕试验表明 ,桔小实蝇在云南的分布可以划分为 3个区域。广南、元江和瑞丽以南的地区为该虫常年发生区。在该区域内 ,桔小实蝇年发生 4- 5代 ,可对瓜果形成周年危害。位于六库、大姚和曲靖以北的地区为该虫的非分布区。本试验未能在该地区诱捕到桔小实蝇或桔小实蝇受害果。位于上述两区域之间的区域为桔小实蝇季节性分布区。桔小实蝇在该地区年发生 2 - 3代 ,出现于 5- 1 1月。桔小实蝇在分布区内不同地区的发生高峰期 ,由南向北逐渐推移 ,如在景洪为 6月而在姚安为 1 0月。在地理垂直分布上 ,该虫主要分布于海拔 50 0 - 2 30 0m范围内 ,而其在 50 0 - 1 0 0 0m范围内发生量最大。研究认为 ,桔小实蝇在上述经度和海拔范围的发生与分布 ,主要与当地气候条件与寄主植物有关。  相似文献   
120.
记述采自海南的小黄蝠Scotophilus temmincki(Horsfield,1824)体表的寄生革螨1新种:吊罗肪刺螨Steatonyssus diaoluoensis sp.nov,.文中给出了中国肪刺螨亚属Steatonyssus 已知种检索表.研究标本保存于贵州大学昆虫研究所标本馆.  相似文献   
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