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Both otoacoustic emissions (OAEs) and auditory evoked potentials (AEPs) are sexually dimorphic, and both are believed to be influenced by prenatal androgen exposure. OAEs and AEPs were collected from people affected by 1 of 3 categories of disorders of sex development (DSD) — (1) women with complete androgen insensitivity syndrome (CAIS); (2) women with congenital adrenal hyperplasia (CAH); and (3) individuals with 46,XY DSD including prenatal androgen exposure who developed a male gender despite initial rearing as females (men with DSD). Gender identity (GI) and role (GR) were measured both retrospectively and at the time of study participation, using standardized questionnaires. The main objective of this study was to determine if patterns of OAEs and AEPs correlate with gender in people affected by DSD and in controls. A second objective was to assess if OAE and AEP patterns differed according to degrees of prenatal androgen exposure across groups. Control males, men with DSD, and women with CAH produced fewer spontaneous OAEs (SOAEs) – the male-typical pattern – than control females and women with CAIS. Additionally, the number of SOAEs produced correlated with gender development across all groups tested. Although some sex differences in AEPs were observed between control males and females, AEP measures did not correlate with gender development, nor did they vary according to degrees of prenatal androgen exposure, among people with DSD. Thus, OAEs, but not AEPs, may prove useful as bioassays for assessing early brain exposure to androgens and predicting gender development in people with DSD.  相似文献   
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INTRODUCTION: Clark ( 1996 ) proposed that abnormal blood flow is related to some congenital cardiovascular malformations (CCVMs), particularly CCVM with obstruction to blood flow. Our hypothesis is that CCVMs may relate to genes that affect blood coagulation or flow. We studied whether polymorphisms of such genes are related to CCVMs; previous association of these SNPs to conotruncal CCVMs is described. METHODS: We assessed risk of pulmonary stenosis (PS, N = 120), atrial septal defect (ASD, N = 108), aortic stenosis (AS, N = 36), and coarctation of the aorta (CoAo, N = 64), associated with 33 candidate genes, selected for their relationship to blood flow affected by homocysteine metabolism, coagulation, cell‐cell interaction, inflammation, or blood pressure regulation. RESULTS: Effects were specific to cardiac phenotype and race. CoAo was associated with MTHFR (?667) C>T (odds ratio [OR] for TT 3.5, 95% confidence limits [CI] 1.4–8.6). AS was associated with a polymorphism of SERPINE1, G5>G4, OR = 5.6 for the homozygote with 95% CI 1.4–22.9. Unique polymorphisms were associated with increased risk of ASD and PS: NPPA 664G>A with ASD (OR of 2.4, 95%CI 1.3–4.4) and NOS3 (?690) C>T with PS (OR 6.1; 95% CI 1.6–22.6 in the African American population only). For ASD, the NPPA (?664) G>A SNP there was increased risk from the variant genotype only in maternal smokers (OR 2.6; 95% CI 1.0–7.2). CONCLUSIONS: Genes affecting vascular function and coagulation appear to be promising candidates for the etiology of cardiac malformations and warrant further study. Birth Defects Research (Part A), 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
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To develop a nonhuman primate model for maternal–fetal transmission of HIV infection, we have inoculated pregnant Macaca nemestrina with uncloned SIVMne. Three animals inoculated during the third trimester delivered healthy infants. One of the three infants, a male born 31 days after the mother was inoculated with SIV, became virus-positive but failed to produce SIV-specific antibody and died with overt simian immunodeficiency and disseminated adenovirus (SV20) infection at age six and one-half months. SIV and adenovirus antigen could be demonstrated by immunohistochemical methods in multiple organ systems.  相似文献   
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Trisomy 13 in humans is the third most common autosomal abnormality at birth, after trisomy 21 and trisomy 18. It has a reported incidence of between 1:5,000 and 1:30,000 live births. It is associated with multiple abnormalities, many of which shorten lifespan. We describe here the first reported case of a baboon (Papio hamadryas) with trisomy of chromosome 17, which is homologous to human chromosome 13. The trisomic infant was born to a consanguineous pair of baboons and had morphological characteristics similar to those observed in human trisomy 13, including bilateral polydactyly in the upper limbs, a patent foramen ovale, and pyelectasis. Molecular DNA analysis using human chromosome 13 markers was consistent with the affected infant inheriting two copies of chromosome 17 derived from the same parental chromosome. This trisomy was, therefore, due to either an error in meiosis II or the result of postzygotic nondisjunction. The parental origin, however, could not be determined.  相似文献   
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目的 联合采用表达谱芯片和下一代测序技术同时高通量筛选先天性心脏病胎儿心肌组织表达差异的miRNA.方法 实验组为孕中期先天性畸形胎儿,对照组为同胎龄无心脏畸形的难免流产的胎儿,取胎儿心室心肌组织,联合采用Agilent Human 2.0 microRNAs表达谱芯片和SOLiD下一代测序技术同时观察心肌组织microRNA的表达变化,数据采用生物信息学方法进行分析,并用实时PCR方法验证芯片结果.结果 通过差异miRNA筛选,发现先天性心脏畸形组在表达谱芯片和下一代测序中共同差异的24个miRNA,生物信息学预测到1 606个靶基因,靶基因Gene Ontology分析表明其中与细胞进程、代谢过程、生物调控相关的靶基因为主,Pathway显著性分析表明,部分靶基因为生物信号通路中的关键因子;随机挑选共同表达差异的4个miRNA进行验证,结果表明定量PCR检测结果与芯片与下一代测序共同筛选结果基本相符.结论 这些在先天性心脏病中异常表达的miRNA为研究先天性心脏病分子水平上的发病机制提供了重要的线索,将有可能为心脏相关疾病的诊断和治疗提供新的靶点和研发新的药物.  相似文献   
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A risk analysis of in utero caffeine exposure is presented utilizing epidemiological studies and animal studies dealing with congenital malformation, pregnancy loss, and weight reduction. These effects are of interest to teratologists, because animal studies are useful in their evaluation. Many of the epidemiology studies did not evaluate the impact of the "pregnancy signal," which identifies healthy pregnancies and permits investigators to identify subjects with low pregnancy risks. The spontaneous abortion epidemiology studies were inconsistent and the majority did not consider the confounding introduced by not considering the pregnancy signal. The animal studies do not support the concept that caffeine is an abortafacient for the wide range of human caffeine exposures. Almost all the congenital malformation epidemiology studies were negative. Animal pharmacokinetic studies indicate that the teratogenic plasma level of caffeine has to reach or exceed 60 μg/ml, which is not attainable from ingesting large amounts of caffeine in foods and beverages. No epidemiological study described the "caffeine teratogenic syndrome." Six of the 17 recent epidemiology studies dealing with the risk of caffeine and fetal weight reduction were negative. Seven of the positive studies had growth reductions that were clinically insignificant and none of the studies cited the animal literature. Analysis of caffeine's reproductive toxicity considers reproducibility and plausibility of clinical, epidemiological, and animal data. Moderate or even high amounts of beverages and foods containing caffeine do not increase the risks of congenital malformations, miscarriage or growth retardation. Pharmacokinetic studies markedly improve the ability to perform the risk analyses.  相似文献   
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