PAPP-A的多态性与冠心病的相关性的研究

【】目的 对冠心病患者的PAPP-A基因多态性进行检测,并探讨其与冠心病之间的关系。 方法 以2014年1月-2015年2月到我院就诊的冠心病患者共100例作为本次研究的研究对象,为实验组。选取同期到我院进行健康体检的健康人共100例作为本次研究的对照组,首先对收集的血液样本进行DNA的提取,然后使用PCR的方式进行基因扩增,PCR的产物则使用ECOR V内切酶进行酶切,使用PAPP-A扩增酶切产物使用琼脂糖(2%)进行凝胶电泳以鉴定PAPP-A的基因型,观察PAPP-A的基因多态性。 结果 PAPP-A基因型共有三种,分别是AA型和CC型两种纯合子和AC型一种杂合子,AA型酶切后表现为77bp1个条带,CC型酶切后则表现为107bp何77bp两个条带,CA型酶切后则表现为107bp、77bp和30bp三个条带。实验组CC型基因型明显高于对照组,实验组C型等位基因的频率高于对照组,且均有P<0.05,差异具有统计学意义。 结论 在冠心病患者体内PAPP-A的基因型发生了明显的变化,主要表现为CC型的基因型增多,C等位基因的频率提高,因此PAPP-A可能与冠心病的发病具有一定的关系,为临床诊断和治疗提供了一定的依据。     

冠心病的的危险因素

根据流行病学调查,近年来我国冠心病发病和死亡有升高趋势。对冠心病的研究也越来越深入。冠心病是多种因素作用于不同环节所致的疾病。这些因素称为危险因素。对这些因素认识和研究的深入,对预防冠心病的发生、早诊断冠心病、提高冠心病的治疗水平等方面,都有重要的作用。冠心病的危险因素很多,现列举如下。     

感染恶性疟原虫的红细胞的小结的电镜观察

Trager等曾报道,被恶性疟原虫感染的红细胞,其膜上常出现电子密集的小结状突起物。这些小结和内皮细胞膜或和其他红细胞膜上的小结形成局部的连接,结果使感染的红细胞贴附在血管内皮上。Kilejian等也曾指出,遮盖小结的红细胞膜部位和其无小结的红细胞膜有着免疫学上的差异。鉴于小结的形态学至今没有弄清,作者试图通过透射电镜、扫描电镜和冰冻断裂及蚀刻技术来观察感染红细胞的膜的变化。     

阻断恶性疟传播的抗体的靶抗原的生物合成

本文研究了恶性疟7G8配子体中3个分子量为260,000、59,000和53,000蛋白的生物合成,它们是能阻断恶性疟传播给蚊虫的单克隆抗体的靶抗原。由体外培养获得含Ⅰ—Ⅴ期配子体的感染细胞。细胞外配子的提纯:将形态学上成熟的配子体,在一定的溶液中保温,刺激配子生成,然后经Percoll进行不连续的梯度离心,在30/42%界面获得细胞外的配子。样品用[~(35)S]蛋氨酸标记,经单克隆免疫沉淀法获得结合的抗原抗体,再用SDS′-聚丙酰凝胶电泳和荧光X线照相术显示标记蛋白带和分子量。     

胰岛素治疗的严重的低血糖

低血糖是接受胰岛素治疗的病人很有威胁一种糖尿病合并症。大多数低血糖发作的症状较轻,且病人可以自我治疗。但一些病人的低血糖发作可以很严重,甚至危及生命。 在用胰岛素治疗的病人中,严重低血糖的真实发病率难以确定,有关这方面的报告很少。Potter等人发现,在用胰岛素治疗的病人中,一年内9%病人有严重的低血糖发作。Barnett等人在八个月的调查期间发现有10%的低血糖发病率。Goldst—ein等人报告了4%的发病率。Hemmann等人最近报告在402例Ⅰ型糖尿病病人中每年有10%的发病率。 作者对澳大利亚的Wollongong地区进行了为     

脑膜炎的脑脊液诊断的进展

脑膜炎的早期诊断对病情和预后影响极大。脑脊液(CSF)的多种指标测定对这组疾病的诊断和鉴别诊断常具有决定性意义。但由于近来疾病的临床变异和CSF改变不典型的病例渐有增加,常造成临床诊断的困难。尽管常规的脑脊液检查仍不失为诊断这类疾病     

衰老的经验性研究的思考

从宏观角度来看 ,衰老研究分为实验性研究和经验性研究〔1〕。实验性研究是一切理论研究基础和根本 ,可进行急性或慢性实验 ,具有可重复性。尽管现代分子生物学与基因技术将衰老的实验及理论研究推进到新的阶段 ,然而现有实验技术或理论的局限性尚无法对一些生命现象进行合理的解释 ,仍属于经验性探索。经验性研究是人们对衰老现象的一种困惑总结 ,现有的衰老学说和理论对这些经验性研究结果暂时无法阐明。目前 ,这种困惑至少表现在三个方面 ,即营养因素、Methuselah效应和绝经对衰老进程的影响。1　营养因素McCay等 (193 5 )最早发现大鼠…     

呼吸系统感染的化学疗法的选择

日本《呼吸》杂志编辑部邀请日本6个大学的专家座谈讨论呼吸系统感染如何选择化学疗法,就11个方面的内容进行介绍。     

中国大陆日本血吸虫品系的研究 Ⅶ.五地隔离群的遗传变异及分化

本文列出了中国大陆安徽、湖北、广西、四川、云南5地日本血吸虫自然隔离群体中多态位点上的等位基因频率和杂合度。根据9个基因位点计算了中国大陆5地日本血吸虫的遗传距离(D)为0.001—0.039,遗传一致性(I)为0.962—0.999。平均基因杂合度(H)为0.332。说明它们的基因结构基本相似,亲缘关系密切。从遗传距离作出的树状图形象地表示了各地自然群体的相对进化关系。     

中国大陆日本血吸虫品系的研究——Ⅵ.多位点酶电泳分析

本文对中国大陆的安徽、湖北、广西、四川、云南5地日本血吸虫的自然隔离群体进行了多位点酶电泳分析。检测了GDH、G6PD、LDH、MDH、PGI、PGM、SOD 7种同工酶的9个基因位点,其中LDH-1、LDH-2、MDH和PGM位点存在两个以上不同等位基因。结果显示多态位点所占的比例为44.4％,说明在大陆境内日本血吸虫的自然隔离群体中存在着不同程度的遗传多态现象。     

Population genetics and phylogenetic analysis of Colorado Borrelia burgdorferi.

Borrelia burgdorferi is transmitted in an enzootic cycle in Colorado between the tick Ixodes spinipalpis and the woodrat Neotoma mexicana. The genetic relationship of Colorado isolates to other B. burgdorferi isolates is unknown nor have relationships among various Colorado isolates been determined. Portions of the flagellin (fla), 66-kD protein, and outer surface protein A (ospA) genes were amplified from 71 Colorado isolates, screened for genetic variability using single strand conformation polymorphism analysis, and unique alleles were sequenced. Colorado isolates were most similar to tick isolates from California and New York isolate 25015. Genetic distances among Colorado ospA sequences were the same or higher than distances among other isolates whereas distances among fla sequences tended to be the same or lower. The index of association (I(A)) was calculated among all loci as a measure of clonality. The I(A) among Colorado isolates was similar to I(A) previously estimated among other United States isolates.     

Genetic characterization of clones of the bacterium Listeria monocytogenes causing epidemic disease.

One hundred and seventy-five isolates of the pathogenic bacterium Listeria monocytogenes recovered from human clinical (blood and cerebrospinal fluid), animal, and environmental sources in Europe, North America, and elsewhere were analyzed electrophoretically for allelic variation at 16 genetic loci encoding metabolic enzymes. Forty-five distinctive allele profiles (electrophoretic types, ETs) were distinguished, among which mean genetic diversity per locus (H) was 0.424. Cluster analysis of a matrix of genetic distances between paired ETs revealed two primary phylogenetic divisions of the species separated at a distance of 0.54. ETs in division I were presented by strains of serotypes 4b, 1/2b, and 4a, whereas strains of ETs in division II were of serotypes 1/2a and 1/2c. Human and animal isolates did not represent distinctive subsets of ETs. The occurrence of linkage disequilibrium between enzyme loci and the widespread distribution of certain ETs indicate that the genetic structure of L. monocytogenes is clonal. One clone, marked by ET1, caused major epidemics of human disease in western Switzerland in the period 1983-1987 and in Los Angeles County, California, in 1985, both of which were attributed to contamination of soft cheese. ET 1 is closely related to the clone (ET7) that caused two large outbreaks of listeriosis in Massachusetts in 1979 and 1983.     

Significant linkage disequilibrium and high genetic diversity in a population of Plasmodium falciparum from an area (Republic of the Congo) highly endemic for malaria

A study based on 28 microsatellite loci was performed on 32 isolates of Plasmodium falciparum from Pointe Noire (Republic of the Congo) and compared with a cosmopolitan sample of 21 isolates collected from different countries in Africa, Latin America, and Asia. The Pointe Noire population exhibited very high genetic diversity (A = 7.8 +/- 2.6, He = 0.79 +/- 0.11). Significant linkage disequilibria were observed in 28 of 378 pairs of microsatellite loci. This result could be explained by two non-exclusive hypotheses: 1) uniparental propagation (i.e., selfing), leading to non-panmictic associations, and/or 2) a Wahlund effect (i.e., spatial population genetic heterogeneity). These observations are in agreement with data previously obtained from isozyme loci of the same isolates, but contrast with other population genetic analyses conducted in other hyperendemic zones.     

Coevolution of host and pathogen populations in the Hordeum vulgare-Rhynchosporium secalis pathosystem.

Isolates of Rhynchosporium secalis collected from two experimental barley populations were scored for putative isozyme, colony color, and virulence loci. Allelic frequencies, multilocus haplotype frequencies, and multilocus genetic structure differed in the two populations of R. secalis; haplotypes also differed widely from each other in virulence. The average virulence of isolates collected from the more resistant host population was greater than the average virulence of the isolates collected from the less resistant host population; also the least virulent haplotype, which made up 19% of the pathogen population collected from the less resistant host population, accounted for only 0.3% of the isolates collected from the more resistant host population. It was concluded that the genetic systems of the barley host and fungal pathogen interacted in a complementary fashion and that the genetic structures of both the host and pathogen populations were shaped by coevolutionary processes featuring interactions among loci affecting many different traits, including interactions among host resistance genes and pathogen virulence genes.     

中国大陆日本血吸虫随机扩增多态DNA(RAPD)的初步研究

目的对中国大陆浙江、安徽、江西、湖北、湖南、四川、云南7省日本血吸虫种群进行遗传变异研究。方法应用随机扩增多态DNA（RAPD）技术，对5条寡核苷酸随机引物扩增。结果获得32条DNA片断，17个基因位点，长度在100bp～2600bp之间。各种群多态百分率（P）为52．9～70．6，平均杂合性（H）为0．269～0．363。中国大陆湖区日本血吸虫各种群间遗传距离（D）为0．000～0．023．山区种群间为0．155，湖区种群与山区种群间遗传距离为0．036～0．139。同时，P235-930bp，P293－910bP分别为四川种群和云南种群特异性DNA片断，P256－720bp为日本血吸虫雌虫特异性DNA片断。对中国大陆日本血吸虫虫株复合性和系统发生作简要讨论。     

Genetic characterization of Entamoeba dispar isolates in Northeast Brazil

The genetic variability of Entamoeba dispar strains was investigated in 39 positive isolates on a survey of 1783 individuals from two different cities of Northeast Brazil (Recife and Macaparana) using two polymorphic species-specific loci (loci 1-2 and 5-6). A combinatory clustering analysis revealed no geographical correlation and remarkable genetic polymorphism among all the isolates examined. Nevertheless, a comparison of the frequency of eight individual PCR products, shared by both Recife and Macaparana populations, for the two loci, showed that only one product of locus 5-6 was significantly different between the two cities. These results suggested that the Macaparana population is infected by similar strains and that locus 5-6 shows potential in assaying questions related to the molecular epidemiology of this region.     

Urinary tract pathology attributed to Schistosoma haematobium: does parasite genetics play a role?

Disease outcome in persons infected with Schistosoma haematobium varies dramatically, ranging from mild symptoms to severe damage of the kidneys and/or bladder. We used ultrasonography to characterize the extent of urinary tract pathology of infected children in Zimbabwe, and random genetic markers to examine the relationship between genetic diversity of S. haematobium and clinical outcome. One hundred thirty-three parasite isolates from 12 students with mild lesions and 13 with severe lesions were compared. Using four randomly amplified polymorphic DNA (RAPD) markers, we scored parasite allelic frequencies at 53 loci. Although parasite heterogeneity did not differ, allelic frequencies at eight loci differed significantly between the mild and severe groups. Parasite isolates were analyzed further using a modified cluster analysis that segregated the population into 13 clusters of associated genotypes. Three clusters were significantly over-represented in children with severe lesions. Our findings, although preliminary, suggest that parasite genetic associations may be important in clinical outcome.     

Markers for population genetic analysis of human plasmodia species, P. falciparum and P. vivax

Present report deals with the genetic diversity existing among the field isolates of Plasmodium falciparum and P. vivax in India. Isoenzymes and molecular markers were used to analyse field isolates of P. falciparum and P. vivax. High level of length polymorphism was observed in repeat nucleotide sequences of MSP-1, MSP-2 and GLURP in P. falciparum isolates and CSP, GAM-1 and MSP-3 alpha in P. vivax isolates. In study populations a high proportion of isolates (up to 60%) were comprised of more than one genetically distinct parasite type--multiclonal. Presence of identical allelic forms of enzyme and DNA variations in different geographical areas and in different years suggest that isolates belong to a single random mating population of P. vivax and P. falciparum. Observed random combination of alleles in the field isolates suggest the unlinked nature of loci studied. Study supports the feasibility of using molecular markers for the identification of recrudescence in P. falciparum from fresh infection.