67例颈后皮肤皱褶增厚胎儿产前诊断结果分析

 目的 探讨颈后皮肤皱褶厚度(nuchal fold, NF)增厚胎儿染色体异常的类型及分布,明确NF增厚的临床意义。方法 以≥14周胎儿NF≥6 mm为NF增厚诊断标准,回顾性分析2013-01至2016-12医院67例NF增厚胎儿的产前诊断临床资料,其中18~23⁺⁶周胎儿行羊膜腔穿刺,≥24周胎儿行超声引导下脐静脉穿刺,死胎在流产后取胎儿组织送检,分析胎儿标本的染色体核型及基因拷贝数变异结果。结果 67例NF增厚胎儿染色体异常发生率为13.4%(9/67),其中21-三体4例,18-三体2例,性染色体异常1例,病理性致病性基因拷贝数变异2例;孤立性NF增厚胎儿的染色体异常发病率为3%(1/33),显著低于综合征性NF增厚胎儿(23.5%,8/34)。结论 NF是胎儿染色体异常的重要指标,对于NF增厚的胎儿的产前诊断,除了常规检查核型以外,还需要重视检测基因拷贝数变异,特别是综合征性的NF增厚胎儿。     

不同结构类型双着丝粒体建立的剂量-效应曲线估算剂量可行性研究

目的 探讨基于不同结构类型双着丝粒体（dicentrics,dic）建立的剂量-效应曲线估算生物剂量的可行性。方法 采集两名健康人外周血样品,用0、0.5、1、2、3、4、5和6 Gy ⁶⁰Co γ射线（剂量率为0.27 Gy/min）离体照射人外周血,常规培养、收获和制备染色体标本,镜下分析并记录不同结构类型dic;应用CABAS软件建立dic剂量-效应曲线;并对两验证样本进行剂量估算。结果 不同结构类型dic率均随受照剂量的增加而升高（R²=0.886~0.943,P<0.01）,各剂量点经典型和单端型dic构成比之和约占所有类型dic的92%以上,而近距型dic和双端型dic分别在各照射剂量点的构成比均<4%。不同结构类型dic剂量-效应曲线的R²值均达到0.998;应用4条曲线估算的受照射剂量差异无统计学意义（P>0.05）。经典型dic剂量-效应曲线估算较高剂量时（3.9 Gy）,相对偏差均≤13.08%。结论 基于不同结构类型dic建立的剂量-效应曲线具有估算生物剂量的可行性。     

In vitro genotoxic and cytotoxic effects of some paraben esters on human peripheral lymphocytes

Parabens (PBs) are p-hydroxybenzoic acid ester compounds commonly employed as antimicrobial preservatives, mainly in food, cosmetic, and pharmaceutical products. The aim of the present study was to investigate the genotoxic and cytotoxic effects of some paraben esters (butyl paraben, propyl paraben, isobutyl paraben, and isopropyl paraben) on human peripheral lymphocytes, using in vitro sister chromatid exchange (SCE), chromosome aberration (CA), and cytokinesis-block micronucleus (CBMN) tests. Lymphocyte cultures were treated with four concentrations of PBs (100, 50, 25 and 10?µg/mL) for 24 and 48?h. Paraben esters significantly induced MN formations as compared to solvent control. Furthermore, butyl paraben and propyl paraben increased MN formations a concentration-dependent manner at 24 and 48?h. PBs increased the CA at 24 and 48?h. However, this increase was not meaningful for butyl paraben and isopropyl paraben at 48?h when compared with solvent control. Butyl, isobutyl, and isopropyl paraben significantly increased the SCE at 24 and 48?h. However, propyl paraben did not induce SCE meaningfully in both treatment periods. A significant decrease in the cytokinesis-block proliferation index and mitotic index was observed in cells exposed to all concentrations of PBs at 24 and 48?h. However, proliferation index was not affected at all concentrations of PBs after 24?h treatment, although it was decreased at the highest concentration of PBs at 48?h. It is concluded that all of the paraben esters used in this study have highly genotoxic and cytotoxic effects on human lymphocytes cells in vitro.     

Chromosome microarray analysis should be offered to all invasive prenatal diagnostic testing following a normal rapid aneuploidy test result

Chromosomal microarray analysis (CMA) has now replaced karyotyping in the analysis of prenatal cases with a fetal structural anomaly, whereas in those pregnancies undergoing invasive prenatal diagnosis with a normal fetal ultrasound, conventional karyotyping is still performed. The aims of this study were to establish the diagnostic yield of CMA in prenatal diagnosis, and to provide new data that might contribute to reconsider current practices. We reviewed 2905 prenatal samples with a normal rapid aneuploidy detection test referred for evaluation by CMA testing. Our study revealed pathogenic and reported susceptibility copy number variants associated with syndromic disorders in 4.8% (n = 138/2905) of cases, being 2.8% (n = 81/2905) the estimated added diagnostic value of CMA over karyotyping. Clinically significant CMA abnormality was detected in 5.4% (107/1975) of the fetuses with ultrasound anomalies and in 1.4% (5/345) of those considered as low-risk pregnancies. Our series shows that in prenatal samples, CMA increases 2-fold the diagnostic yield achieved by conventional karyotyping.     

孕妇产前诊断指征与胎儿染色体异常的关系

目的探讨产前诊断指征和产前诊断胎儿染色体异常间的关系。方法选择2018年6月至2018年12月于贵港市人民医院就诊的孕妇100例,收集所有孕妇产前诊断指征的资料,同时收集羊膜腔穿刺术检测胎儿染色体核型分析的结果。结果胎儿染色体异常共9例,总异常率占9.00%,其中无创基因检测异常组的胎儿染色体异常检出率为60.00%,明显高于高龄组的3.03%、唐氏筛查高危组的5.26%及胎儿超声异常组的7.69%,差异均有统计学意义(P<0.05);夫妇染色体异常组的胎儿染色体异常检出率为50.00%,明显高于高龄组,差异均有统计学意义(P<0.05);高龄组、唐氏筛查高危组、胎儿超声异常组间异常检出率无明显差异(P>0.05)。结论产前诊断指征与胎儿染色体异常密切相关,羊膜腔穿刺行染色体核型分析,能够有效检出胎儿染色体异常,对于有产前诊断指征的孕妇应尽早接受产前诊断,以降低新生儿出生缺陷的发生率。     

BRAF V600E mutant oligodendroglioma‐like tumors with chromosomal instability in adolescents and young adults

We performed genome‐wide methylation analysis on 136 pediatric low‐grade gliomas, identifying a unique cluster consisting of three tumors with oligodendroglioma‐like histology, BRAF p.V600E mutations and recurrent whole chromosome gains of 7 and loss of 10. Morphologically, all showed similar features, including a diffusely infiltrative glioma composed of round nuclei with perinuclear halos, a chicken‐wire pattern of branching capillaries and microcalcification. None showed astrocytic features or characteristics suggestive of high‐grade tumors including necrosis or mitotic figures. All tumors harbored multiple chromosomal copy number abnormalities (>10 chromosomes altered), but none showed 1p/19q co‐deletion or IDH1 p.R132H mutation. Hierarchical clustering and t‐stochastic neighbor embedding analyses from DNA methylation data cluster them more closely to previously described pediatric‐type low‐grade gliomas and separate from adult gliomas. These tumors exhibit distinct clinical features; they are temporal lobe lesions occurring in adolescents and young adults with a prolonged history of seizures and all are alive with no recurrence (follow‐up 3.2 to 13.2 years). We encountered another young adult case with quite similar pathological appearance and molecular status except for TERT promoter mutation. Although the series is small, these may represent a new category of IDH wild‐type low‐grade gliomas which may be confused with “molecular GBM.” Further, they highlight the heterogeneity of IDH wild‐type gliomas and the relatively indolent behavior of “pediatric‐type” gliomas.     

Relevance of microscopic indicators of chromosomal instability in routine reporting of malignancies

Chromosomal instability (CIN) is the defining feature of most human cancers. The role of CIN has been suggested in diagnosis and prognostication of the tumors since long. However, the molecular methods used for its identification are costly, require expertise and may not be available in many of the laboratories. Therefore, this article tries to revisit the already described morphological indicators of CIN like multipolar mitoses, chromatin bridges, chromatin strings, nuclear heterogeneity, laggards, nuclear buds, micronuclei, and multinucleated micronucleated cells. The role of above as morphological biomarkers in diagnosis and prognosis of various cancers has been reviewed and the possibility of their inclusion in day to day reporting of malignancies is also discussed. Diagn. Cytopathol. 2014;42: 181–188. © 2013 Wiley Periodicals, Inc.