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1.

Introduction

The Mycobacterium tuberculosis East African-Indian (EAI) spoligotyping family (belonging to lineage 1, Indo-Oceanic, defined by the region of deletion RD239) is distributed worldwide, but is more prevalent in Southeast Asia, India, and East Africa. Studies in Latin America have rarely identified EAI. In this study, we describe the occurrence of the EAI family in Brazil.

Methods

EAI was identified in a systematic literature review of genetic diversity studies pertaining to M. tuberculosis in Brazil, as well as in a survey conducted in Salvador, Bahia, located in the northeastern region of this country.

Results

The EAI6-BGD1 spoligotyping family and the EAI5 Spoligotype International Type (SIT) 1983 clade were the most frequently reported, with wide distribution of this particular clade described in Brazil. The distribution of other EAI spoligotyping patterns with broader worldwide distribution was restricted to the southeastern region of the country.

Conclusions

EAI may be endemic at a low frequency in Brazil, with some clades indicating increased fitness with respect to this population.  相似文献   
2.

Objective

To evaluate the virological outcomes in children and adolescents infected with HIV-1 in Salvador, Bahia according to genotyping results.

Methods

We retrospectively evaluated the rates of virological suppression of children and adolescents submitted to HIV-1 genotyping test from January/2008 to December/2012. The participants were followed in the two referral centers for pediatric AIDS care, in Salvador, Brazil. Resistance mutations, drug sensitivity profiles, and viral subtypes were analyzed using the Stanford HIV-1 Drug Resistance Database. Adherence was estimated by drugs withdrawal at pharmacies of the two sites.

Results

101 subjects were included: 35 (34.6%) were drug-naïve, and the remaining 66 were failing ART. In drug-naïve group, 3 (8.6%), presented with NNRTIs resistance mutations, along with polymorphic mutations to PIs in most (82.8%) of them. Among the failing therapy group, we detected a high frequency (89.4%) of resistance mutations to PIs, NRTI (84.8%), and NNRTI (59.1%). Virological suppression after introduction/modification of genotyping-guided ART was achieved only for patients (53.1%) with drug withdrawal over 95%. Main detected HIV-1 subtypes were B (67.3%), F (7.9), C (1.9%), and recombinant forms (22.9%).

Conclusions

Despite the use of genotyping tests in guidance of a more effective antiretroviral regimen, poor adherence to ART seems to be the main determinant of low virological suppression rate for children and adolescents, in Salvador, Brazil.  相似文献   
3.

Background

S and s antigens of the MNS system are of clinical importance because alloanti-S and -s have usually caused delayed hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. Various red cell genotyping has been established to predict the phenotypes to solve serological test limitations.

Objectives and methods

This study aimed to determine S and s genotype frequencies and to estimate the alloimmunization risks among central, northern and southern Thai populations. Altogether, 1237 blood samples from Thai blood donors were included. Only 150 samples were tested with anti-S and anti-s by indirect antiglobulin test. All samples were genotyped for GYPB*S and GYPB*s alleles using inhouse PCR with sequence-specific primer. Additionally, the allele frequencies were used to estimate alloimmunization risks and compare with other populations.

Results

The phenotyping and genotyping results in 150 samples were in 100% concordance. The allele frequencies of GYPB*S in central, northern and southern Thais were 0.061, 0.040 and 0.097, and GYPB*s were 0.939, 0.960 and 0.903, respectively. The frequencies among central Thais were similar to those among northern Thai and Korean populations (P?>?0.05) but significantly differed from those of Asian, Caucasian African American and Hispanic populations (P?<?0.05). In addition, the risk of S alloimmunization among southern Thais (0.1566) was higher than those among central (0.1038) and northern Thais (0.0736).

Conclusion

This was the first study to report S and s predicted phenotypes and estimate alloimmunization risks among Thais, which is beneficial to prevent transfusion-induced alloimmunization among donors and patients.  相似文献   
4.

Introduction

Survivin is an apoptosis inhibitor and plays a primary role in cancer development and progression. One of the most common polymorphism of the survivin promoter -31G/C (rs9904341) influences its expression and is associated with the risk of cancer development. This study was conducted to explore survivin promoter gene -31G/C (rs9904341) polymorphism and the risk of breast cancer.

Patients and Methods

The study group included 190 pathologically confirmed breast cancer patients, in addition to 200 distinct cancer-free controls from Jammu and Kashmir region of India, where breast cancer is the most common cancer in women. Single nucleotide polymorphism genotyping for -31G/C polymorphism in the survivin promoter region was done using a polymerase chain reaction-restriction fragment length polymorphism method.

Results

The variant genotype/allele was found in 54.1% of the cases compared with 46.5% of controls. The combined prevalence of genotype GC+CC was significantly higher in patients compared with the control group (P = .02). Analyses of odds ratios (ORs) in the patient and control groups indicated that the presence of homozygous CC genotype was associated with increased risk for development of breast cancer (OR, 2.04; 95% confidence interval [CI], 1.07-2.98). The gene frequencies for G and C alleles were statistically different between patient and control groups (OR, 1.37; 95% CI, 1.03-1.84).

Conclusion

The results suggest the association of -31G/C survivin polymorphism at a genotypic and allelic level in breast cancer.  相似文献   
5.
目的:建立一种多重 PCR 方法用于莫西沙星耐药的艰难梭菌鉴定和初步基因分型。方法根据艰难梭菌 slpA 可变区间核苷酸序列的差异设计5种 slpA 基因型(gr、hr、fr、gc08和078)的特异性 PCR 引物,同时加入检测艰难梭菌管家基因磷酸甘油醛异构酶基因 tpi 的种特异性引物,构建多重PCR 方法;利用9种肠道常见的正常或致病菌验证多重 PCR 方法的特异性,利用46株分属于11个slpA 基因型的艰难梭菌参考菌株来验证方法的检测和分型能力;利用建立的多重 PCR 方法检测39株莫西沙星耐药的临床菌株,以 slpA 测序分型法为参照方法,评估该方法的临床实用性。结果多重PCR 检测9种肠道常见的正常或致病菌 tpi 和5种 slpA 基因型均为阴性;46株艰难梭菌参考菌株 tpi均为阳性,36株分属于5种靶 slpA 基因型(gr、hr、fr、gc08和078)的菌株被正确分型,10株分属于其他6种基因型的参考菌株均无法分型。39株莫西沙星耐药的艰难梭菌临床菌株 tpi 均为阳性,32株检出具体基因型,其中22株为 slpA 基因型 gc08,6株为 hr,2株为 fr,2株为078,与 slpA 测序分型结果一致;7株多重 PCR 无法分型,slpA 测序分型结果显示其基因型均不包含在多重 PCR 分型范围内。结论成功建立一种简单、快捷、临床实验室适用的艰难梭菌检测,且能够分辨出5种 slpA 基因型的多重PCR 方法;莫西沙星耐药的艰难梭菌主要为 slpA 基因型 gc08。  相似文献   
6.
目的 鉴定天津市手足口病病原体柯萨奇病毒A组2、4、5、6和10型,并分析其VP1区基因及分子流行病学特征.方法 提取45株非EV71非CV-A16肠道病毒分离株核酸,利用RT-PCR法扩增其VP1基因并测序,然后根据VP1区基因核酸序列,进行肠道病毒型别鉴定和同源性分析,构建种系发生树.结果 45株非EV71非CV-A16肠道病毒天津分离株分别为6株柯萨奇病毒A组2型(Coxsackie virus A2,CV-A2),14株CV-A4,3株CV-A5,8株CV-A6和14株CV-A10.柯萨奇病毒各型的株间核酸序列同源性均在80%以上,各型分离株与原型株的同源性均在71.2% ~ 85.8%之间.天津各型分离株在种系发生树上均聚集于各自相对独立的分支,与国内流行株处在同一分支内,而与国外原型株处于不同的进化分支.结论柯萨奇病毒A组2、4、5、6和10型成为天津市手足口病的流行病原体,各型天津分离株株间核酸序列同源性较高,呈现一定的区域聚集性.  相似文献   
7.
目的 分析番禺地区RhD阴性献血者部分D(partial D)基因分型特征.方法 采用微量板法对献血者进行RhD阴性筛查;采用抗人球蛋白法对初筛RhD阴性的样本进行确认;采用PCR-SSP法(RH基因变异体分型检测试剂盒)对献血者基因组DNA进行扩增,对扩增产物进行电泳分析,根据电泳图谱判断部分D基因分型.结果 初筛检出60例RhD阴性,经抗人球蛋白法确认59例为RhD阴性,阴性频率约为0.23%.59例RhD血清学筛选阴性的基因分型检测发现2例部分D,血清学筛选RhD阴性中出现部分D的频率约为3.4%.结论 本地区血清学RhD阴性献血者中,存在RHD-CE (5)-D、RHD-CE(6-9)-D等位基因型,采用PCR-SSP法对RhD阴性表型献血者进行基因分型,可以准确鉴定RHD基因型.  相似文献   
8.
目的:探讨MIRU-VNTR技术在杭州地区结核分枝杆菌氧氟沙星耐药株基因分型中的应用。方法收集杭州市2010年4月-2012年6月各结核病定点医院分离培养的临床菌株,进行药物敏感性检测。分别采用RD105缺失基因检测法和MIRU-VNTR技术对氧氟沙星耐药株进行菌株鉴定和基因分型。结果筛选出的52株氧氟沙星耐药株中,43株(82.69%)为北京家族菌株。经12个MIRU-VNTR位点组合分析,52株氧氟沙星耐药株呈52种MIRU-VNTR基因型,总Hunter-Gaston指数( HGI)为0.999。除MIRU40和ETR-F外,其他10个MIRU-VNTR位点对北京家族菌株和非北京家族菌株均显示较高或中等程度的分辨率。结论筛选到的10个MIRU-VNTR位点具有较高分辨率,适用于杭州地区结核分枝杆菌氧氟沙星耐药株分型。  相似文献   
9.
目的 调查安徽及周边省份绵羊和山羊隐孢子虫流行情况及分子特性。方法 选择安徽省及其周边的河南、江苏和山东部分地区的7个规模化绵羊场和10个规模化山羊场,分别采集832份和781份新鲜绵羊和山羊粪便样品,利用隐孢子虫SSU rDNA基因特异的巢氏PCR技术对所有样品进行检测,调查上述地区绵羊和山羊隐孢子虫感染和虫种分布;对获得的微小隐孢子虫和泛在隐孢子虫进行gp60基因扩增与分析,以鉴定其基因亚型。结果 安徽及周边省份绵羊和山羊隐孢子虫感染率分别为5.8%(48/832)和8.7%(68/781)。SSU rDNA基因分析显示,绵羊感染的隐孢子虫为肖氏隐孢子虫和泛在隐孢子虫,山羊感染的隐孢子虫为微小隐孢子虫。gp60基因分析显示,泛在隐孢子虫基因亚型均为XIIa亚型2,微小隐孢子虫基因亚型均为IIdA19G1。结论 人兽共患泛在隐孢子虫XIIa亚型2和微小隐孢子虫 IIdA19G1基因亚型的鉴定,提示绵羊和山羊可能为人隐孢子虫感染的潜在来源。  相似文献   
10.
目的:探索包头地区HPV感染人群的分布情况及主要基因分型,为防治提出对策措施。方法:采用描述性研究方法,选取2020年7月—12月检测HPV的就诊女性作为研究对象,调查研究对象的一般情况、疾病状况,同时采集其宫颈上皮脱落细胞,采用PCR-反向点杂交法进行HPV分型检测。结果:调查的1 138例患者中检测出HPV感染者254例,感染率22.32 %;其中低危型感染率为13.59 %,高危型感染率为86.41 %;多重感染76例,占29.92 %。感染前5位分别为HPV16:19.69 %;HPV52:17.32 %;HPV53、HPV58、HPV42:11.02 %。年龄分组中,60~70岁组检测感染率最高,为32.69 %。就诊分布中,妇科门诊为226人(88.98 %)。就诊原因中,仅12人(4.72 %)主动进行HPV感染检测。结论:HPV感染主要以单一型感染为主,高危型感染占比高;应加强健康教育,提高主动检测意识,利于HPV感染的早发现、早诊断、早治疗。  相似文献   
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