高温致金黄地鼠神经管畸形中细胞凋亡的组织学观察

为研究细胞凋亡与高温致神经管畸形的关系，采用核固红－结晶紫染色方法和电镜技术，观察高温后胚胎发育变化。结果显示，高温后８ｈ胚胎发育迟滞，神经管延迟闭合或不闭合，胚胎各段尤期是头部的神经上皮和周围间充质的细胞凋亡比对照组增多，其超微结构改变为染色质浓缩，边聚，核膜皱缩，微绒毛消失并出现异常的包质突起；１６ｈ后细胞凋亡明显增多，胞质内出现了大量空泡，凋亡小体增多；     

应用抑制性消减杂交技术筛选及鉴定高温致金黄地鼠神经管畸形下调表达基因

目的克隆高温致金黄地鼠神经管畸形下调表达基因，探讨其分子生物学机理。方法应用抑制性消减杂交技术构建高温致畸金黄地鼠胚胎神经管反向消减cDNA文库；联合蓝白斑和菌落PCR方法筛选阳性克隆进行测序和同源性分析；用Northern印迹方法证实这些基因的表达。结果成功构建高温致畸金黄地鼠胚胎神经管反向消减cDNA文库，从中筛选到15个基因，均与GenBank中已知基因有同源性。Northern印迹证实这些基因在高温致畸胚胎神经管中均呈下调表达。结论发现了高温致金黄地鼠神经管畸形过程中的一些重要相关基因并对其功能进行了初步探讨。     

高温致金黄地鼠神经管畸形的上调表达基因筛选及其鉴定

目的:筛选高温致金黄地鼠神经管畸形的上调表达基因,探讨其分子生物学机制。方法:通过抑制性消减杂交技术获得消减产物,转化大肠杆菌DH5α,构建高温致金黄地鼠胚胎神经管畸形的消减cDNA文库;联合蓝白斑和菌落PCR方法筛选含插入片段的阳性克隆,进行测序和同源性分析,并经Northern杂交技术检测基因的表达。结果:成功构建高温致金黄地鼠胚胎神经管畸形的消减cDNA文库,其中2个克隆插入片段的基因序列与小鼠磷酸甘油酸酯激酶(Pgk-1)同源。Northern杂交证实该基因在高温致畸胚胎神经管的表达较其在同龄正常胚胎神经管明显升高。结论:Pgk-1的上调表达可能与高温致神经管畸形密切相关。     

酒精致金黄地鼠神经管和眼畸形的实验研究

目的 观察酒精致金黄地鼠胚胎神经管和眼畸形发生过程的形态学改变,并定量观察致畸过程中的细胞凋亡。方法 实验组孕金黄地鼠分别用腹腔注射酒精致畸处理后4、8、16、24、48和72h剖腹取胚或胎,在光镜、体视显微镜和扫描电镜下观察胚胎神经管和眼的畸形发生中的形态变化;借助TUNEL法和透射电镜,定量研究神经管和眼畸形发生过程中的细胞凋亡。结果 1．酒精可使金黄地鼠神经管和视杯的发生明显延迟。2．酒精处理后8h,神经上皮细胞凋亡显著增加,尤以前脑和神经嵴处明显;16h和24h,凋亡仍大量存在,主要位于神经嵴和延迟发生的视沟部位;48h后神经上皮细胞凋亡逐渐减少。结论 酒精可使金黄地鼠神经管和视杯的发生明显延迟,神经上皮和视泡、视杯上皮细胞过度凋亡,这可能是酒精致神经管和眼畸形的机理之一。     

高温致神经管缺陷过程中凝集素受体变化的实验动物研究

妊娠金黄地鼠随机分为实验组和对照组,前者于受精后第８天置４２℃水浴中持续２０ｍｉｎ,后者置３７℃水浴中持续２０ｍｉｎ。分别于高温后８、１２、２４、４８ｈ剖腹取胎,石蜡包埋,连续切片。应用生物素标记的花生凝集素、刀豆凝集素、麦胚凝集和荆豆凝集素为分子探针作亲合细胞化学染色,对各期鼠胚神经上皮及其基膜、脊索和神经管周围间充质中相应受体糖基进行定性、定位和半定量观察。结果显示,正常胚胎神经上皮及其周围组     

高温致畸金黄地鼠神经管cDNA文库的构建与鉴定

目的:构建高温致畸金黄地鼠神经管cDNA文库。方法:在高温致神经管畸形动物模型上,提取高温致畸金黄地鼠胚胎神经管总RNA,用SMARTTMcDNA文库构建试剂盒反转录合成cDNA第1链,经LD-PCR合成全长双链cDNA,去除小于500 bp的片断后与λTriplEx2噬菌体左、右臂连接,体外包装,构建成未扩增cDNA文库,再进行文库扩增。测定未扩增和扩增文库的滴度及重组率;随机挑取噬菌斑,经PCR扩增,电泳检测所构建cDNA文库的质量。结果:未扩增文库滴度为2.03×106pfu/ml,重组率为98.4%,文库扩增后滴度达2.503×109pfu/ml,重组率为97.6%。插入片段长度分布于500~3 000 bp之间。结论:成功地构建了高质量的高温致畸金黄地鼠神经管cDNA文库。     

高温致神经管畸形动物模型的建立及其形态发生的研究

将妊娠第８ｄ的金黄地鼠腹部置４２℃水浴２０ｍｉｎ，建立了一个致畸率高、致死率低、效果稳定、操作简便的高温致畸动物模型，并在此模型上，探讨了高温致ＮＴＤ的形态发生机理。结果表明：高温有明显的胚胎毒和致畸作用，且与高温值和持续时间明显相关。     

高迁移率族蛋白B1在脂多糖致幼年大鼠脑损伤中的表达

目的 探讨高迁移率族蛋白B1(high mobility gnmp box 1,HMGB1)在脂多糖(LPS)致幼年大鼠脑损伤中的表达变化.方法 SD大鼠随机分为对照组(NS组,n=80),颈外动脉注射生理盐水;脂多糖组(LPS组,n=80),颈外动脉注射LPS,于注射药物后6、12、24、48、72 h处死,甲酰胺法测脑组织伊文思蓝(EB)含量;免疫组织化学技术检测脑组织HMGBI、神经元特异性烯醇化酶(NSE)、胶质纤维酸性蛋白(GFAP)的表达;RT-PCR技术检测HMGB1 mRNA的表达变化.结果 LPS组脑组织的EB含量、NSE、GFAP蛋白表达均为6 h开始增加,24 h达高峰;HMGB1蛋白及HMGB1 mRNA于6 h开始增加,24 h达高峰,与EB含量、NSE、GFAP蛋白含量呈正相关.各时间点与NS组比较,差异显著.结论 HMGB1可能作为晚期炎症因子参与LPS致脑损伤的发生发展过程.     

aFGF在高温致神经管畸形中作用的免疫组织化学研究

在已建立的高温致神经管畸形的动物模型上，用免疫组织化学方法，对高温处理后的孕鼠之不同发育阶段的胚胎进行酸性成纤维细胞生长因子免疫组织化学染以，观察其在各期胚胎的神经上皮及春周围间充质，内界膜和脊索中的分布和变化。     

应用银染mRNA差异显示法寻找高温致神经管畸形差异表达基因

目的 :寻找高温致神经管畸形的差异表达基因。方法 :在高温致神经管畸形的动物模型上 ,分别于高温处理后 2 4、48和 72小时 ,提取鼠胚神经管组织总RNA和正常对照组鼠胚相应时间的神经管组织总RNA ,反转录合成cDNA第一链后进行差异显示PCR扩增 ,采用PAGE和银染技术显示差异条带 ,回收差异条带并经PCR二次扩增后 ,用点杂交方法筛除假阳性条带 ,再用Northern印迹杂交进一步鉴定。结果 :在高温致畸的鼠胚神经管组织中筛选到一个特别明显的差示cDNA片段N3 2 ,该片段所在基因在高温致畸的胚胎神经管组织中的表达远低于正常同龄胚的神经管组织。结论 :N3 2片段所在基因的低表达与高温致神经管畸形相关。     

Open neural tube defects: Immunocytochemical demonstration of neuroepithelial cells in amniotic fluid

Cytologic evaluation of second trimester amniotic fluid (AF) is a rapid, inexpensive adjunct to prenatal diagnosis of open neural tube defects (ONTDs). Our goal was to determine whether the neural-appearing cells and/or large foamy macrophages in the AF of anencephalics are indeed of neural and/or glial origin. In two second trimester patients with elevated serum alpha-fetoprotein (AFP) and polyhydramnios, fetal sonogram studies showed anencephaly; amniocentesis was performed for AF-AFP, cytogenetic, and cytologic studies. AF sediment smears were initially Papanicolaou-stained; next, the same smears were immunoperoxidase (IP)-stained for glial fibrillary acidic protein (GFAP). If GFAP negative, slides were restained for synaptophysin (SYN) and neuron-specific enolase (NSE). Both AFs contained small neural-appearing cells (5–10 μm) singly and in clusters, with dense, round, homogeneous nuclei, an occasional nucleolus, and scant cytoplasmic rim. These were GFAP negative and SYN and NSE positive; the large vacuolated, lipid-laden macrophages (20–40 μm) were negative for all three IP stains. In conclusion, positive IP staining for SYN and NSE supports the morphologic impression that small dark cells in AF are of neural origin, while negative IP staining of large foamy macrophages suggests nonneural, nonglial origin. Diagn. Cytopathol. 16:143–144, 1997. © 1997 Wiley-Liss, Inc.     

CD1+ cells in mothers of stillborn infants with neural tube defects

In healthy individuals, CD1+ cells are found in thymic tissue, but not in peripheral blood. The thymus, as a key organ of the neuroendocrine system, frequently shows gross abnormalities in infants with neural tube defects. In order to study the immuno-logic significance of fetal thymic findings, maternal T-lymphocyte subpopulations were investigated. In 10 mothers of healthy new-borns, 5 mothers of stillborn infants who had no gross abnormalities, and 5 mothers of stillborn infants with neural tube defects, CD1+, CD3+, CD4+, and CD8+ cells were studied. Only the mothers of the infants with open neural tube defects showed CD1 + cells in their peripheral blood. © 1995 Wiley-Liss, Inc.     

Novel mutations in VANGL1 in neural tube defects

Neural tube defects (NTDs) are severe congenital malformations caused by failure of the neural tube to close during neurulation. Their etiology is complex involving both environmental and genetic factors. We have recently reported three mutations in the planar cell polarity gene VANGL1 associated with NTDs. The aim of the present study was to define the role of VANGL1 genetic variants in the development of NTDs in a large cohort of various ethnic origins. We identified five novel missense variants in VANGL1, p.Ser83Leu, p.Phe153Ser, p.Arg181Gln, p.Leu202Phe and p.Ala404Ser, occurring in sporadic and familial cases of spinal dysraphisms. All five variants affect evolutionary conserved residues and are absent from all controls analyzed. This study provides further evidence supporting the role of VANGL1 as a risk factor in the development of spinal NTDs. © 2009 Wiley‐Liss, Inc.     

LPS通过p38MAPK-CBP诱导巨噬细胞RAW264.7表达和释放HMGB1

 目的 检测LPS刺激后小鼠腹腔巨噬细胞HMGB1和相关信号分子p38MAPK、NF-κB、CBP的表达,探讨脓毒症时巨噬细胞表达和释放HMGB1的信号传导机制。 方法 采用LPS刺激RAW264.7细胞,在不同的时间点用免疫细胞化学、激光共聚焦显微镜观察细胞内相关信号分子p38MAPK、NF-κB、CBP的变化,ELISA检测培养上清HMGB1的含量,Real-time PCR检测培养细胞HMGB1的mRNA水平,Western blot检测胞浆和胞核内HMGB1的含量。 结果 随着LPS的刺激,细胞浆内p38MAPK的绿色荧光逐渐增强,NF-κB的绿色荧逐渐减弱,而细胞核内NF-κB绿色荧光逐渐增强,CBP的绿色荧光逐渐增强,三者均于刺激后6 h达高峰。LPS刺激后12-48 h培养细胞胞浆和上清中HMGB1蛋白含量逐渐增加,而12-24 h胞核内HMGB1含量逐渐减少,36 h后又逐渐增多,各不同时间点差异具有显著性(P<0.01);而细胞内HMGB1 mRNA表达在LPS刺激后0-12 h无明显变化, 24 h、36 h和48 h明显增高,与0h相比差异有显著性(P<0.01)。 结论 LPS通过依次激活巨噬细胞内信号分子p38MAPK、NF-κB及CBP来诱导HMGB1的合成、转位和释放表达的。     

The thymic findings in stillborns with neural tube defects

Neural tube defects are among the most common congenital anomalies causing perinatal deaths. Other organ system anomalies may be associated with neural tube defects: for instance, various types of thymus pathology have been reported in these patients. In this study thymic changes were investigated in 30 stillborns with neural tube defects seen between January 1988 and June 1989. Thymic weights were significantly reduced in 14 cases and increased in 7. One patient had a double thymus, and in two cases no thymus tissue could be found. These findings suggest a primary developmental defect of the neural crest, affecting the orderly development of the thymus gland.