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1.
目的研究广西HIV-1 CRF01-AE重组毒株env基因V3环序列变异及其与生物表型间的关系。方法从广西主要流行区收集来的50份HIV-1感染者血液样本中提取前病毒DNA,使用巢式聚合酶链反应(nested-PCR)扩增HIV-1 env基因片段并进行亚型鉴定,选择38份CRF01-AE重组型HIV-1毒株env,基因V3环及邻近区域的序列进行系统树和氨基酸变异分析。结果38份CBF01-AE重组毒株中36份与分离于广西地区的CRF01-AE.97CNGX2f和泰国代表毒株THCM240接近,另外2份与中非共和国代表株90CF402聚成一簇;CRF01-AE重组毒株V3环顶端四肽存在着4种类型:CPCQ、GPGR、GPGH和GPGA;根据V3环关键氨基酸推测辅助受体使用情况,结果显示:71.05%的CRF01-AE重组毒株可能使用CCR5作为辅助受体,28.95%不能对其辅助受体的使用情况做出预测。结论广西HIV-1 CRF01-AE重组毒株V3顶端四肽变异较大,而且大部分毒株可能为NSI型。这可为广西该毒株的防治和诊断试剂的更新提供参考。  相似文献   

2.
山东省部分HIV-1流行株的亚型分析和序列特征研究   总被引:1,自引:0,他引:1  
目的 对山东省HIV 1流行毒株进行亚型分析 ,并研究其变异特征。方法 采集 2 6份HIV 1感染者的外周静脉抗凝血 ,提取前病毒DNA进行体外扩增 ,获得包膜蛋白 (env)基因的核酸片段 ,并对其C2 V3及邻区的核苷酸进行测定和分析。结果 基因和氨基酸序列分析表明 ,2 6份标本中存在 4种亚型和重组毒株 (B′、C、A、A/E) ,其中B′ 17株 ,其组内基因距离为 11.6 9± 4 .19。V3环顶端四肽有 6种形式 ,最多的是GPGQ(15株 )、GPGR(6株 )。V3环第 11、2 5位氨基酸出现变异 ,并有 1株呈电荷双阳性。结论 山东省HIV 1流行株亚型较多 ,有重组毒株出现的可能 ,基因发生较大变异 ,HIV 1传播在山东省有加快的趋势。  相似文献   

3.
目的 研究我国人类免疫缺陷病毒 1型 (HIV 1)B、C亚型主要流行株在感染过程中基因变异的特点及其与选择压力的关系。方法 应用巢式聚合酶链反应 (nested PCR)对 2 5 8例HIV 1感染者血样中的HIV 1外膜蛋白 (env)基因进行扩增 ,并使用ABI 377型测序仪对扩增产物测序后 ,选择其中 37份B亚型和 35份C亚型HIV 1毒株env基因包括V3~V4区的序列进行比较分析 ,并计算和分析氨基酸同义替换与非同义替换的比值 (Ks Ka)。结果 B亚型毒株V3~V4区的基因离散率高于C亚型毒株。无论B亚型 ,还是C亚型毒株 ,其V4区基因序列较V3区变异更大。在C亚型毒株中 ,V3区基因序列变异甚至比V3上游区和C3区小。B和C亚型毒株整个V3~V4基因区的Ks Ka比值均 <1,差异有非常显著性 (P <0 0 0 1) ,其中B亚型毒株以V3区的Ks Ka比值最小 ,而C亚型毒株则以V4区的Ks Ka比值最小。结论 B和C亚型毒株env基因的变异主要发生在V4区而不是V3区。C亚型毒株V3区较V3上游区和C3区还要保守 ,是本研究的特殊发现。这两种亚型在我国快速流行中发生的变异是在选择压力下发生的 ,而不是随机进化的结果 ,而且选择压力对这两种亚型毒株V3、V4区的作用程度也不一样。这将为我国艾滋病防治策略的制定和疫苗研究提供科学的依据。  相似文献   

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目的 分析某地区有偿献血人员中流行的人免疫缺陷病毒1型( HIV-1) gag、pol、env基因亚型及基因变异特征.方法 提取HIV-1感染者外周血单核细胞(PBMC) DNA,经巢式PCR( Nested PCR)扩增gag(p17-p24)、pol( PR-RT)、env(C2-V5)基因片段,纯化测序后用MEGA5.0等生物学软件对核苷酸序列进行分析.结果 23份样本为B亚型,2份为B亚型与C亚型重组,1份为CRF01_AE与B亚型重组.PR区未发现蛋白酶抑制剂主要耐药性突变,RT区检测到核苷类逆转录酶抑制剂耐药性突变M184V和非核苷类逆转录酶抑制剂耐药性突变K101E,G190A.结论 流行于该地区的HIV-1毒株以B亚型为主.大多数毒株对常规抗病毒药物仍然敏感,使用HARRT治疗方案依然有效.CXCR4型辅助受体的毒株顶端四肽多为GPGR(91.7%),提示GPGR可能与疾病的进展有关.  相似文献   

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目的分析某地区有偿献血人员中流行的人免疫缺陷病毒1型(HIV-1)gag、pol、env基因亚型及基因变异特征。方法提取HIV-1感染者外周血单核细胞(PBMC)DNA,经巢式PCR(NestedPCR)扩增gag(p17-p24)、pol(PR*RT)、env(C2-V5)基因片段,纯化测序后用MEGA5.0等生物学软件对核苷酸序列进行分析。结果23份样本为B亚型,2份为B亚型与C亚型重组,1份为CRF01-AE与B亚型重组。PR区未发现蛋白酶抑制剂主要耐药性突变,RT区检测到核苷类逆转录酶抑制剂耐药性突变M184V和非核苷类逆转录酶抑制剂耐药性突变K101E,G190A。结论流行于该地区的HIV-1毒株以B亚型为主。大多数毒株对常规抗病毒药物仍然敏感,使用HARRT治疗方案依然有效。CXCR4型辅助受体的毒株顶端四肽多为GPGR(91.7%),提示GPGR可能与疾病的进展有关。  相似文献   

6.
目的 了解北京市男男性接触人群(MSM)中HIV-1的最新流行趋势及膜蛋白V3环序列特征.方法 巢式聚合酶链式反应(n-PER)扩增2007年提取的北京市男男性接触HIV感染者基因组DNA样品,对膜蛋白基因C2-V3区测序,进行病毒亚型及V3环序列特点分析.结果 11例样本中,4例是欧美B亚型,5例是AE重组亚型,1例是BC重组亚型,1例是01B重组亚型.V3环顶端四肽以GPGQ和GPGR为主.结论 北京市男男性接触HIV-1感染者中重组亚型呈蔓延流行趋势.  相似文献   

7.
目的建立一种快速简便的基因分型方法,对广西HIV-1重组毒株env基因区进行亚型鉴定。方法从HIV阳性样品中提取核酸,使用HIV-1M组通用引物对env区进行第一轮扩增,第二轮则使用分别检测B′/C或C亚型和CRF01-AE亚型的二套特异性引物放入同一反应管中进行扩增,根据不同亚型扩增的目的带位置不同来判断亚型。将通用引物扩增出的所有样本均进行基因测序和系统树分析以验证结果。结果50份样本中,经基因测序和系统树分析证实CRF08-BC样本3份(6%),CRF01-AE样本43份(86%),4份(8%)样本无法确定亚型。经亚型特异性引物PCR法检测得出B′/C或C亚型样本3份(100%),CRF01-AE样本39份(90.7%),灵敏度为91.3%,特异度为100%。两种方法检测结果经差异性检验显示X^2=2.25,P〉0.05,差异无统计学意义,结果一致者占92%。与基因分析结果吻合。重复实验显示CRF08-BC平均重复性为100%(10/10),CRF01.AE为93.8%(61/65)。结论该方法是一种简便、快速、低成本,具有高度灵敏性和特异性的HIV-1毒株env基因区分型法,能够直接对广西HIV-1 CRF01-AE重组毒株进行鉴定。  相似文献   

8.
目的 观察云南静脉药瘾 (IDUs)HIV 1分离株env基因V3环顶端四肽氨基酸和相应核苷酸序列随时间推移的变化。方法 根据 1990~ 1997年间 6 2株HIV 1分离株env基因C2 V3区DNA序列 ,对HIV 1膜蛋白V3环顶端四肽基因序列 (基序 )及其编码核苷酸进行分析 ,并探讨其随时间推移的变化趋势。结果  1990~ 1997年间 6 2株HIV 1毒株膜蛋白V3环顶端四肽基序有程度不同的氨基酸变异 ,主要表现在第四位氨基酸的改变 ,变异呈现一定的趋向性。 6 2株云南标本中有 46例(74 2 % )为GPGR ,10例 (16 1% )为GPGQ ,4例 (6 4% )为GPGK ,另有 2例 (3 3% )为GPER且四肽基序编码核苷酸的变异主要表现为A→G的改变。结论  1990~ 1997年这一时期内 ,云南IDUs特定感染者范围内HIV 1分离株膜蛋白V3环顶端四肽序列已表现出较大的趋向性 ,符合HIV 1国际B亚型SF2株的GPGR模式  相似文献   

9.
目的了解黑龙江省内部分人免疫缺陷病毒1型(HIV-1)的亚型及基因序列特征。方法用巢式聚合酶链反应(nested-PCR),对黑龙江省内17份HIV-1感染者外周血单个核细胞(PBMC)中前病毒脱氧核糖核酸的膜蛋白(env)基因进行扩增,并对C2-V3的核苷酸序列进行测定和分析。结果系统树分析显示,17份样本中病毒与HIV泰国B(B’)亚型聚在一起,基因离散率为(6.94±1.01)%,与欧美B亚型基因离散率为(12.94±2.19)%,与其他亚型的离散率大于20%。对于其V3环四肽序列的分析表明,具有GPGQ的8例,占47.06%;具有GPGR的7例,占41.18%;1例为GQGR;1例为GPGH。通过序列分析预测,大部分利用CCR5辅助受体。结论所检测的黑龙江省17例HIV-1均为B’亚型,提示黑龙江省的HIV-1流行株可能以B’亚型为主,其V3环顶端四肽序列特征以GPGQ和CP(承为主。  相似文献   

10.
目的 探索我国河南省新蔡县既往献血人群中HIV-1病毒流行株env基因V3环顶端四肽多态性和pol基因原发耐药性变异特征.方法 套式聚合酶链反应(Nested-PCR)扩增51例确认HIV阳性样本env、pol基因部分区段并测序,PCR产物纯化后克隆,挑选克隆株鉴定为阳性后测序,以MEGA(version 3.0)等软件进行分析.结果 env基因V3环顶端四肽主要为GPGR、GPGQ、GPGK、GQGR;在pol基因PR区未发现有关蛋白酶抑制剂(PIs)的主要耐药性突变位点,在RT区共发现9条序列存在对NRTIs或NNRTIs中的一类药物耐药性突变.结论 GPGR这一典型的欧美B亚型V3环顶端四肽序列比例最高为44.44%;原发性耐药发生的比例较低,药物敏感性资料表明耐药性突变位点多表现为低度耐药性,因此提示我们在对该地区因献血感染HIV的患者在首次治疗时可不必以耐药性检测做指导.  相似文献   

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There are three principal pressures driving the development of in vitro toxicology: (1) the need for more efficient testing systems to cope with the large number of xenobiotics currently being developed; (2) public pressure to reduce animal experimentation; and (3) a need for a better understanding of the mechanisms of toxicity. Within this, in vitro toxicology is focused on local, systemic, and target-organ toxicity. It is becoming increasingly apparent that a step or decision-tree approach using input of a variety of experimental data (physicochemical properties, biokinetics, cytotoxicity) provides the most efficient system for predicting toxicity. Examples of the use of in vitro toxicity systems for prediction of systemic toxicity and target-organ (liver) toxicity are presented.Originally presented at ECCP 93.  相似文献   

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Between December 1999 and December 2004, 40 081 pregnant women were examined for toxoplasmosis with Toxo-IgG, Toxo-IgM enzyme immunoassay. Women with positive results were then retested with the Toxo-IgG avidity assay for recent toxoplasmosis. Recent acute toxoplasmosis in pregnant women was found to be significantly more frequent (p < 0.01) during winter than summer. The incidence of acute toxoplasmosis during winter-spring was also significantly more frequent (p < 0.025) than summer-autumn. This phenomenon should be taken into account when formulating preventive measures for toxoplasmosis, especially for pregnant women.  相似文献   

15.
Liu P  Gupta N  Jing Y  Zhang H 《Neuroscience》2008,155(3):789-796
Polyamines putrescine, spermidine and spermine are positively charged aliphatic amines and have important roles in maintaining normal cellular function, regulating neurotransmitter receptors and modulating learning and memory. Recent evidence suggests a role of putrescine in hippocampal neurogenesis, that is significantly impaired during aging. The present study measured the polyamine levels in memory-related brain structures in 24- (aged), 12- (middle-aged) and 4- (young) month-old rats using liquid chromatography/mass spectrometry and high performance liquid chromatography. In the hippocampus, the putrescine levels were significantly decreased in the CA1 and dentate gyrus, and increased in the CA2/3 with age. Significant age-related increases in the spermidine levels were found in the CA1 and CA2/3. There was no difference between groups in spermine in any sub-regions examined. In the parahippocampal region, increased putrescine level with age was observed in the entorhinal cortex, and age did not alter the spermidine levels. The spermine level was significantly decreased in the perirhinal cortex and increased in the postrhinal cortex with age. In the prefrontal cortex, there was age-related decrease in putrescine, and the spermidine and spermine levels were significantly increased with age. This study, for the first time, demonstrates age-related region-specific changes in polyamines in memory-associated structures, suggesting that polyamine system dysfunction may potentially contribute to aged-related impairments in hippocampal neurogenesis and learning and memory.  相似文献   

16.
Adrenomedullin (AM) is a new peptidergic regulator of vascular function. AM serves as a hormone, which has many biological properties, plays an important role in the many pathophysiological processes, especially shock. This review will highlight the structure, biological properties of AM and the relationship between AM and shock.  相似文献   

17.
The age at menarche was estimated by recollection in 1617 women between the ages of 18 and 60 in Madrid and a nearby suburb, Pinto. The population of Pinto is working-class and the Madrid group, taken from residential neighbourhoods , belongs to the upper middle class. In both groups we found a diminution in average age at menarche, from 14.04 to 13.02 years in Madrid and from 14.55 to 13.16 years from about 1935 to about 1965 in Pinto. These changes have been more intense in the group which is less well-off economically, where living conditions have varied much more drastically.  相似文献   

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Pitfalls in TRAP assay in routine detection of malignancy in effusions   总被引:5,自引:0,他引:5  
Telomerase has been found to be reactivated in a majority of cancers but is inactive in most somatic cells. Our principal goal was to determine the potential use of the telomeric repeat amplification protocol (TRAP) assay as marker for malignancy in cytological effusions. The simple selection criterion was the cytological diagnosis, and routine samples were classified into malignant (58 samples) and nonmalignant (233 samples). Of the malignant samples, 44/58 (76%) were positive by TRAP assay. Of the 14 telomerase-negative cytology-positive samples, RNA integrity was poor in 9, indicating suboptimal sample conservation for molecular analysis. In 3 of the remaining 5 samples with a negative TRAP assay, a high number of malignant cells was observed, and these cells might have been telomerase-negative. Thus, the sensitivity of TRAP assay for the presence of malignant cells was about 76%. In the cytologically nonmalignant effusions, the presence of telomerase activity was observed in 24% (55/233). Of these, 6% were highly suspicious for malignancy, 9% were doubtful, and 9% were cytologically nonmalignant effusions confirmed by a follow-up of 12 mo or more. According to these data, the specificity of the TRAP assay to detect tumor cells in effusions ranged only between 82-91%. Our results indicate that, although the TRAP assay is positive in 6-15% of putative malignant effusions, the relatively high number of TRAP false-negative and false-positive cases renders this test unsuitable for routine diagnostic purposes.  相似文献   

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