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21.
Sequence differences in the dimerization initiation signal (DIS) affect the rate of recombination between subtype B and subtype C HIV-1. To test the hypothesis that DIS sequences can be used to predict intersubtype recombination potentials, we measured the recombination rate between CRF01_A/E (AE) and B, which contain mismatches in the DIS, and between AE and C, which have an identical DIS. Compared with the intrasubtype recombination rate, the recombination rate between AE and subtype B virus was 9-fold lower, and the rate between AE and subtype C virus was 2-fold lower. Thus, DIS sequences can be used to predict the recombination potential between HIV-1 subtypes. Further analyses revealed that the 2-fold lower recombination rate between AE and C viruses can be restored to the intrasubtype recombination rate by matching a part of the LTR and a portion of the viral genome. Therefore, the lower intersubtype recombination rate between AE and C is not caused by a given region but is a cumulative effect by more than one region. 相似文献
22.
Stefan Steurer Pascale Sophia Mayer Meike Adam Antje Krohn Christina Koop Daniel Ospina-Klinck Ali Attarchi Tehrani Ronald Simon Pierre Tennstedt Markus Graefen Corinna Wittmer Benedikt Brors Christoph Plass Jan Korbel Joachim Weischenfeldt Guido Sauter Hartwig Huland Maria Christina Tsourlakis Sarah Minner Thorsten Schlomm 《European urology》2014
Based on next-generation sequencing of early-onset prostate cancer (PCa), we earlier demonstrated that PCa in young patients is prone to rearrangements involving androgen-regulated genes—such as transmembrane protease, serine 2 (TMPRSS2)–v-ets avian erythroblastosis virus E26 oncogene homolog (ERG) fusion—and provided data suggesting that this situation might be caused by increased androgen signaling in younger men. In the same study, an accumulation of chromosomal deletions was found in cancers of elderly patients. To determine how age-dependent molecular features relate to cancer phenotype, an existing data set of 11 152 PCas was expanded by additional fluorescence in situ hybridization analyses of phosphatase and tensin homolog (PTEN), 6q15 and 5q21. The results demonstrate that the decrease in TMPRSS2–ERG fusions with increasing patient age is limited to low-grade cancers (Gleason ≤3 + 4) and that the significant increase in the deletion frequency with age was strictly limited to ERG-negative cancers for 6q15 and 5q21 but to ERG-positive cancers for PTEN. These data suggest that the accumulation of non–androgen-linked genomic alterations with advanced patient age may require an appropriate microenvironment, such as a positive or negative ERG status. The strong link of ERG activation to young patient age and low-grade cancers may help to explain a slight predominance of low-grade cancers in young patients. 相似文献
23.
目的了解北京市中心城区流感病原学特征,为流感防治提供依据。方法采集北京市两家国家级流感监测哨点医院全年流感样病例(ILI)咽拭子标本,对北京市中心城区的病例标本进行分析,采用狗肾传代细胞(MDCK)进行流感病毒分离,采用血凝抑制试验(HI)进行型别鉴定。结果全年共检测北京市中心城区ILI咽拭子标本1 968件,分离到流感病毒162株,分离阳性率为8.2%,经分离鉴定,其中新甲型H1N1亚型96株,A(H3N2)亚型60株,B/Y亚型6株,分别占总株数的59.3%、37.0%和3.7%。结论 2013年1~2月为北京市中心城区流感发病高峰,流行株为新甲型H1N1亚型和A(H3N2)亚型,流感在5岁年龄均有分布且存在性别差异。 相似文献
24.
Occurrence of respiratory syncytial virus subtypes in hospitalized children in Cleveland, Ohio from 1985 to 1988. 总被引:1,自引:0,他引:1
In order to determine the frequency of occurrence of the two respiratory syncytial virus (RSV) subtypes in hospitalized children in Cleveland, Ohio, we analyzed clinical isolates obtained during three consecutive winter epidemic seasons between 1985 and 1988. RSV was recovered from the frozen clinical specimens of 197 patients: 176 subtype A, and 21 subtype B. Subtype A predominated during all three epidemic seasons, ranging from 83 to 94% of isolates. We surveyed the clinical records of 16 children with subtype B, and 101 children with subtype A infections, hospitalized at the University Hospitals of Cleveland during these winter epidemics and found no differences in age, sex, race, or clinical spectrum of severity of disease caused by the two subtypes. In contrast to previously reported data, subtype A predominated in each of the winter seasons studied within this community. We conclude that both subtypes circulate concurrently within the community during the winter. In hospitalized children both subtypes appear to cause a similar spectrum of disease. Both the concurrent circulation of RSV subtypes and the similar spectrum of illness pose for important considerations in the development of effective vaccines against this common respiratory agent in children. 相似文献
25.
目的 了解福建省HIV-1 新近感染者流行毒株的亚型分布和流行特征。方法 随机抽取福建省2011-2012 年使用BED捕获酶免疫试验检出的104 例新近感染者血样标本,采用反转录巢式PCR扩增,gag、pol 和env 基因片段,并测定和分析核酸序列。结果 目标人群中存在B亚型和01_AE、07_BC、08_BC、55_01B 四种流行重组型,其中以01_AE 和07_BC 流行重组型为主,分别占45.68%和35.80%。基因亚型的流行特征分析显示,亚型分布中01_AE 所占比例下降,07_BC 所占比例上升;性传播是主要感染途径,其中同性传播比例明显上升。结论 福建省HIV-1 流行毒株亚型分布众多,随着时间推移,亚型构成和传播途径已发生改变,应加强对HIV-1感染的分子流行病学趋势动态监测。 相似文献
26.
芽囊原虫(Blastocystis)是一种可寄生于人类和多种动物的单细胞、厌氧性肠道原虫,在全球广泛分布.芽囊原虫感染在我国健康人群、儿童、学生、门诊及住院患者、腹泻等人群中均有报道,免疫力低下人群感染率较高,广西和云南地区人群感染率相对较高.根据小亚基核糖体RNA (small-subunit ribosomal R... 相似文献
27.
28.
目的 分析重庆市高危人群中HIV-1亚型的流行情况。方法 对采自重庆市经性传播和静脉吸毒途径感染的3份HIV-1阳性外周血分离PBMC,扩增env基因C_2-V_3区核酸片段,并进行核苷酸序列分析。结果 在其中一孕妇体内发现一株G亚型HIV-1毒株序列的存在,这是G亚型HIV-1毒株首次在中国被发现,同时有母婴传播的可能;另外两例被证明为E亚型和C亚型HIV-1毒株。结论 这表明HIV在重庆市高危人群中已有流行并且流行情况复杂。 相似文献
29.
30.
北京市性传播HIV-1感染者流行毒株gag基因序列测定和亚型分析 总被引:1,自引:0,他引:1
目的 了解北京市性传播HIV-1感染者流行毒株亚型特点和流行规律.方法 随机采集北京市2008年新确证性传播HIV感染者的抗凝全血标本100份,分离血浆,提取病毒RNA,用套式聚合酶链反应扩增病毒gag基因,并进行序列测定和亚型分析.结果 系统进化分析确定北京市性传播HIV-1感染者流行毒株存在8个亚型或流行重组型,分别为B亚型22份,B'亚型8份,C亚型1份,CRF01_AE 38份,CRF02_AG 2份,CRF07 BC 9份,CRF08_BC 3份,疑似C/CRF01_AE重组型1份.结论 CRF01_AE和B亚型分别占45.2%和26.2%,为性传播感染者主要的亚型,应该加强我市HIV-1亚型流行情况的监测.Abstract: Objective To investigate the subtype distribution and sequence characteristics of HIV-1 strains prevalent among sexual infectors in Beijing. Methods We collected the blood samples from 100HIV sexual infectors in Beijing during 2008 and separated plasma specimens. RNA was extracted from the plasma and the gag gene was amplified by RT-PCR and nest-PCR. The PCR products were sequenced directly and phylogenetic analyses of gag gene was performed using the MEGA4 software. Results Among 100 HIV-1 plasma samples,84 gag gene fragments were amplified and analyzed. Eight HIV subtypes including B(22 strains), B'(8 strains),C( 1 strain) ,CRF01_AE (38 strains) ,CRF02_AG (2 strains) ,CRF07_BC(9 strains) ,CRF08_BC(3 strains) and C/CRF01_AE recombinant like strain( 1 strain) were identified circulating in Beijing. Conclusion CRF01 _AE and subtype B were predominant in Beijing account for 45.2% and 26.2% and the surveillance of HIV gene variation should be paid more attention. 相似文献