小鼠睾丸支持细胞的分离培养与鉴定

目的:分离培养小鼠睾丸支持细胞并进行鉴定.方法:取18～20 d雄性小鼠的睾丸,酶消化法原代培养.用RT-PCR的方法克隆带有锌指结构域的支持细胞基因SERZ,与pcDNA3.0连接后构建重组质粒pcDNA3.0-SERZ.用Kpn Ⅰ和XbaⅠ分别酶切质粒pcDNA3.0-SERZ,获得线性化模板进而合成探针.原位杂交检测SERZ mRNA在培养细胞中的表达;用RT-PCR的方法检测雄激素结合蛋白(ABP)在支持细胞中的表达.结果:支持细胞多为多边形,核呈三角形或不规则形,染色浅,核仁明显,细胞完全铺开,成膜状,相邻细胞之间交织连接,细胞纯度为(85.1±2.5)%.SERZ mRNA在培养细胞的胞质中高水平表达.RT-PCR结果表明我们分离的支持细胞能够表达ABP mRNA.结论:我们成功分离和鉴定了小鼠睾丸支持细胞,纯度为(85.1±2.5)%.     

低氧预处理诱导骨髓间充质干细胞Pim-1激酶高表达抑制细胞凋亡

BACKGROUND: Bone marrow mesenchymal stem cells have a low survival rate after implanted into the ischemic myocardium. However, hypoxia preconditioning (HPC) may enhance bone marrow mesenchymal stem cell proliferation and promote its survival rate. OBJECTIVE: To explore whether Pim-1 is involved in HPC protecting against apoptosis of bone marrow mesenchymal stem cells and the relevant mechanism. METHODS: Bone marrow mesenchymal stem cells were respectively subjected to HPC for 0, 6, 12, and 24 hours. The expression of Pim-1 and apoptosis-related genes were detected by RT-qPCR and western blot. Then, the best hypoxic preconditioning time was determined as 12 hours. Then, bone marrow mesenchymal stem cells were assigned to one of the following groups: control (without HPC), 12-hour HPC, 12-hour HPC+Pim-1 inhibitor groups. Flow cytometry analysis was used to detect the cell apoptosis, Transwell assay to analyze the cell migration ability in each group, and JC-1 kit to detect mitochondrial membrane potential. Animal models of myocardial infarction were established. One week after modeling, bone marrow mesenchymal stem cells were given via multi-point injection around the infarct zone of rats. Two weeks after modeling, heart tissues of rats were taken and sliced followed by DiI staining to calculate the survival rate of bone marrow mesenchymal stem cells. Additionally, rat cardiac function was assessed by echocardiography prior to and after modeling as well as at 4 weeks after cell transplantation. RESULTS AND CONCLUSION: At 12 hours after HPC, the expression of Pim-1, p-Akt and Bcl-2 gene in the infarct region was significantly increased, but the expression of caspase-3 and Bax was significantly decreased. Compared with the control group, cell viability in the 12-hour HPC group was increased very significantly at 1 week after cell transplantation (P < 0.001), the migration and anti-apoptosis ability were enhanced significantly (P < 0.01) and the cardiac function of rats was significantly improved in the 12-hour HPC group (P < 0.05). All of these protective effects were blocked by the Pim-1 inhibitor. These findings indicate that HPC can protect bone marrow mesenchymal stem cells from apoptosis through activating Akt and up-regulating Pim-1, and thereby improve the therapeutic effect of bone marrow mesenchymal stem cell transplantation on ischemic heart diseases. 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程      

胚胎干细胞向生殖细胞分化的研究进展

近年来,人们探索如何在体外诱导胚胎干细胞获得配子,以了解性别决定的基因调控和环境影响.这些研究都是用胚胎干细胞（embryonic stem cell,ES）建立1个类原始生殖细胞（primordial germ cell-like cells）的细胞群体,然后移植到睾丸或继续培养从而获得雄性或雌性配子.原始生殖细胞的迁移和向生殖干细胞的分化依赖于自身基因表达以及与周围细胞的相互作用.本文将对原始生殖细胞分化为雄性生殖细胞（有少许为雌性生殖细胞）的关键环节、原始生殖细胞和生殖干细胞分化过程中的标志物做一综述.     

氯乙烯诱导小鼠胚胎神经管发育畸形的研究

目的观察孕早期不同剂量氯乙烯(VC)染毒后胎鼠神经系统发育以及神经上皮细胞增殖和凋亡的变化情况,明确VC对神经系统发育的致畸作用。方法将孕鼠21只按完全随机设计分组法分为实验组和对照组,实验组分别用不同剂量的VC对孕6.5 d的小鼠进行腹腔染毒,对照组注射花生油,均于E12.5取胚胎。观察胎鼠的表观发育情况,计算胚胎畸形率以及神经系统异常的发生率。运用PCNA免疫组织化学技术和TUNEL染色技术检测并观察神经管上皮细胞的增殖及其凋亡的变化。结果①中剂量VC组胎鼠活胎率下降,活胎中畸胎发生率高达51%,其中神经管畸形发生率占40%,与正常对照组相比差异有统计学意义(P<0.05);高剂量VC组胎鼠活胎率仅占55%,活胎中畸胎率明显增高占71%,其中神经管畸形发生率占50%,与正常对照组相比差异有统计学意义(P<0.01)。②中剂量和高剂量VC组胚胎神经管上皮厚薄不一致;高剂量组神经管多数呈明显未闭合状,神经管周围的间充质细胞肿胀,轮廓不清。③正常小鼠神经管神经上皮内可见PCNA阳性细胞与TUNEL阳性细胞分布;实验组各型阳性细胞分布与对照组相似,但随着染毒剂量的增加,PCNA阳性细胞表达减少,而TUNEL阳性细...     

星形胶质细胞活化与癫痫发作及其调控作用的研究进展

癫痫是一种常见的脑功能障碍综合征,超同步神经放电是癫痫症的一个特点,它源于脑部过多神经细胞的同时过度兴奋,从而引起突然而短暂的脑功能失调.癫痫发作后临床表现为突然昏倒、神志丧失、口吐涎沫、四肢抽搐;最为显著的特点是不可预测和反复发作,其发病机制一直不很清楚.在癫痫患者中,儿童和青少年仍是癫痫的高发人群,发作类型80%是全身性(大)发作.因此,对于癫痫发病机制的研究一直是国内和国际神经科学界研究的热点之一.