An evaluation of the challenges to developing tumor BRCA1 and BRCA2 testing methodologies for clinical practice

Ovarian cancer patients with germline or somatic pathogenic variants benefit from treatment with poly ADP ribose polymerase (PARP) inhibitors. Tumor BRCA1/2 testing is more challenging than germline testing as the majority of samples are formalin‐fixed paraffin embedded (FFPE), the tumor genome is complex, and the allelic fraction of somatic variants can be low. We collaborated with 10 laboratories testing BRCA1/2 in tumors to compare different approaches to identify clinically important variants within FFPE tumor DNA samples. This was not a proficiency study but an inter‐laboratory comparison to identify common issues. Each laboratory received the same tumor DNA samples ranging in genotype, quantity, quality, and variant allele frequency (VAF). Each laboratory performed their preferred next‐generation sequencing method to report on the variants. No false positive results were reported in this small study and the majority of methods detected the low VAF variants. A number of variants were not detected due to the bioinformatics analysis, variant classification, or insufficient DNA. The use of hybridization capture or short amplicon methods are recommended based on a bioinformatic assessment of the data. The study highlights the importance of establishing standards and standardization for tBRCA testing particularly when the test results dictate clinical decisions regarding life extending therapies.     

Development of clinical genetics in Asia

This Special Issue on Clinical Genetics in Asia highlights a collection of articles showing the growth, development, and current status of clinical genetics in Asia. In this Introduction, the Guest Editors share on the themes of this issue to provide useful insights into the rapid growth of genomics and clinical genetics in this region. The contents of this Issue cover a range of topics from the history and development of clinical genetics in Asia to studies on disorders with clinical significance or phenotype differences in the Asian populations to the status of precision medicine. The goal is to provide a glimpse of how significantly the field of genetics in Asia has developed in recent years with the aspiration that this can serve as a catalyst to increase international collaboration and cooperation in combating genetic diseases. We hope that this issue shows Asia's readiness and willingness to be a part of more international conversations about genetics in future.     

葛根黄酮对亚急性衰老模型小鼠抗氧化作用的研究

目的：考察葛根黄酮对衰老模型小鼠抗氧化能力的影响。方法：用D-半乳糖制备衰老模型小鼠,分为正常对照组、模型组、阳性对照组、高、低剂量组,检测各组小鼠血清丙二醛（MDA）、超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-PX）水平变化。结果：葛根黄酮能显著降低衰老小鼠血清MDA水平,同时可提高SOD和GSH-PX活力水平。结论：葛根黄酮对亚急性衰老模型小鼠具有抗氧化作用。     

2a型HCV E1、E2/NS1区基因cDNA的克隆及序列分析

目的：了解丙型肝炎病毒（HCV）2a型基因组E1 E2／NS1区序列，为进一步研究HCV包膜蛋白的生物学功能奠定基础。方法：用逆转录套式PCR（RT－nPCR)从江苏省1例丙型肝炎患者血清中扩增出两条分别约770bp、1100bp的片段，分别以限制性内切酶EcoR I、BamH I和EcoR I、Hand Ⅲ双酶切后连入pUC19载体中，转化感受态细胞，经限制性酶切长度多态性分析（RFLP）和PCR法证实为阳性克隆后，用全自动序列分析仪测序。结果：分别测得约770bp、1100bp的核苷酸序列，拼接后得到的完整核苷酸序列及其编码的氨基酸序列分别与HCV－1、HC－C2、HCV－BK、HC－J6、HC－J8相应序列作比较，显示分离株HCV在核苷酸水平上与以上分离株的同源性分别为60．5％、60．1％、59．7％、87．8％、67．5％；在氨基酸水平上的同源性分别为67．3％、66．4％、65．0％、87．8％、79．0％。结论：分离株（HCV－JS）与HC－J6同属2a型，但同源性有一定差异。     

Immune biology of macaque lymphocyte populations during mycobacterial infection

Immune responses of lymphocyte populations during early phases of mycobacterial infection and reinfection have not been well characterized in humans. A non-human primate model of Mycobacterium bovis bacille Calmette-Guerin (BCG) infection was employed to characterize optimally the immune responses of mycobacteria-specific T cells. Primary BCG infection induced biphasic immune responses, characterized by initial lymphocytopenia and subsequent expansion of CD4+, CD8+ and gammadelta T cell populations in the blood, lymph nodes and the pulmonary compartment. The potency of detectable T cell immune responses appears to be influenced by the timing and route of infection as well as challenge doses of BCG organisms. Systemic BCG infection introduced by intravenous challenge induced a dose-dependent expansion of circulating CD4+, CD8+ and gammadelta T cells whereas, in the pulmonary compartment, the systemic infection resulted in a predominant increase in numbers of gammadelta T cells. In contrast, pulmonary exposure to BCG through the bronchial route induced detectable expansions of CD4+, CD8+ and gammadelta T cell populations in only the lung but not in the blood. A rapid recall expansion of these T cell populations was seen in the macaques reinfected intravenously and bronchially with BCG. The expanded alphabeta and gammadelta T cell populations exhibited their antigen specificity for mycobacterial peptides and non-peptide phospholigands, respectively. Finally, the major expansion of T cells was associated with a resolution of active BCG infection and reinfection. The patterns and kinetics of CD4+, CD8+ and gammadelta T cell immune responses during BCG infection might contribute to characterizing immune protection against tuberculosis and testing new tuberculosis vaccines in primates.     

升结肠自主神经瘤的临床病理诊断

目的：报道1例升结肠自主神经瘤（GANT）的临床病理特征及诊断和鉴别诊断。方法：通过HE、免疫组化及电镜观察1例结肠GANT并复习文献。结果：主要由梭形、多角形或上皮样细胞组成、胞质丰富、淡嗜酸性、核仁清楚,间质血管较丰富。瘤细胞免疫表型为vimentin,NSE,S-100蛋白及CD34阳性;CgA弱阳性;而actin,desmin,HHF35,Mac387,Syn,CK及HMB45阴性。电镜观察瘤细胞类似神经元、见细长的细胞突起和致密轴心神经分泌颗粒,瘤细胞间可见丝团样纤维。结论：GANT是胃肠道间质瘤中具有神经元分化的一种特殊类型、发生在结肠罕见。其组织形态应与平滑肌性肿瘤、神经鞘瘤等鉴别。     

一个遗传性凝血因子Ⅶ缺陷症家系的基因与表型分析

目的:研究遗传性凝血因子Ⅶ(FⅦ)缺陷家系基因与表型的特点。方法:一个遗传性FⅦ缺乏家系19名成员的FⅦ及其他凝血因子促凝活性检测和用PCR及DNA序列检测FⅦ基因缺陷,初步探讨遗传性FⅦ缺乏的血液凝固变化。结果:在这一家系中,FⅦ缺乏伴FⅫ∶C下降或FX∶C增高的,在临床上无明显出血现象;FⅦ缺乏症与其基因10827核苷酸C→T突变有关。结论:遗传性FⅦ缺乏发生临床出血除与FⅦ∶C水平有关外,还可能与FⅫ∶C和FⅩ∶C变化引起的凝血和纤溶活性改变有关。     

中国HCV5′-非编码区复合酶切分型及其3b基因型序列分析

目的　研究中国丙型肝炎病毒 (HCV)不同基因型感染分布情况 ,并对 3b序列进行分析。方法　采用逆转录 聚合酶链反应 (RT PCR)技术扩增HCV5’NCR 1a、1b、2a、2b、3a、3b、4a、6a不同基因型的cDNA及 187份HCVRNA阳性样品中cDNA。A应用BHH (BsrBI、HaeⅡ、HinfI)复合内切酶消化 5′ NCRcDNA ,B应用BstUⅠ消化 ,C应用HaeⅢ消化 ,电泳检测片段大小。结果　 187例HCVRNA阳性患者ABC分型结果表明 ,1b型感染率占 6 7 38% ,2a型 12 30 % ,1b/ 2a型为5 88% ,3b型 5 35 % ,2b型 3 2 1% ,2a/ 2b、1b/ 2b型各为 2 14 % ,1a型 1 0 7,6a型 0 5 4 %。 3份 3b基因型 5’ NCRA T克隆测序结果表明 ,3株 3b型之间同源性为 99 5 4 %～ 10 0 %。其中chiKQ5 0与GI5 14 395 3a株为 96 2 8%与GI6 76 8773b株同源性为 98 6 % ,与 1a型为 93 4 9% ,与 1b型为94 88% ,与 2a型为 91 6 3% ,与 2b型为 89 30 % ,与 4a型为 95 35 % ,与 6a型为 93 4 % ,结论　研究结果表明该项分型技术既保证了RT PCR检测灵敏度 ,又具有良好的分型效果。提示 :该分型方法不仅适合中国HCV基因型检测 ,对亚洲及欧洲和非洲HCV分型研究也具有一定的参考价值     

尿纤维蛋白降解产物（FDP）半定量测定在诊断膀胱癌中意义的临床研究

目的：探讨尿中纤维蛋白降解产物在诊断膀胱癌中的意义，寻求对人群进行膀胱癌筛查的简易、有效的方法：方法：以乳胶凝集半定量测定法分别测定正常人、良性血尿患者、膀胱癌患者各50人尿中FDP浓度。结果：正常对照组中42例尿FDP〈2μg/ml、8例2μg／ml；良性血尿组尿FDP浓度35例〈2μg／ml、12为2μg／ml、3例4μg／ml；膀胱癌组：6例2μg／ml、11例4μg/ml、26例8μg/ml、7例16μg／ml。膀胱癌组与正常对照组和良性血尿组之间FDP浓度具有显著性差异：进行比较，（P值分别为〈0．01、〈0．05）。结论：检测尿FDP浓度是一种简单有效的检出膀胱癌的方法，可望用于健康人群普查以便于早期发现膀胱癌。