大鼠内细胞团和胎儿神经干细胞构建嵌合体的潜力

嵌合体大鼠是研究人类疾病的重要动物模犁.用囊胚注射法研究了大鼠内细胞团(ICM)和胎儿神经干细胞(FNS)构建嵌合体的潜力.结果发现来自黑色(DA)大鼠第5天(D5)和第6天(D6)囊胚的ICM细胞注入D5 Sprague-Dawley(SD)大鼠囊胚后得到3只嵌合体大鼠:D5 SD大鼠ICM细胞注射入D5 DA囊胚后得到4只嵌合体大鼠:而体外培养的DA或SD人鼠ICM细胞注射后均未能获得嵌合体大鼠.本研究用大鼠胎儿神经干细胞(rFNS)和LacZ转染的rFNS构建嵌介体,未能获得嵌合体人鼠:但在LacZ转染的SD rFNS注射到DA大鼠囊胚后发育来的41只胎儿中,有2只胎儿其组织切片中发现少量LacZ阳性细胞.结果表明DA和SD大鼠ICM具有参与嵌合体发育的潜力,但ICM细胞经体外培养后构建嵌合体的潜力显著F降(P＜0.05);大鼠胎儿神经干细胞构建嵌合体的潜力较低,可能仅具有参与早期胚胎发育的潜力.     

胚泡着床窗口的分子调控

着床窗口是指当胚胎发育到胚泡阶段时,子宫也增殖和分化到可接受状态,二者相互作用使胚泡着床的短暂时间.雌激素和孕酮是该过程的综合调控分子,它们通过多种局部信号分子的介导,使子宫中的各种细胞类型增殖、分化,为着床窗口的开放做出相互协调的反应.子宫与胚胎在着床窗口通过前列腺素、组织胺、降钙素、多种细胞因子和生长因子的旁分泌作用进行分子对话,使胚泡滋养层与子宫内膜上皮发生附着反应.着床窗口一旦开放,即自动向非接受态转化.     

转基因受体酵母菌的低能氩离子注入研究

通过不同剂量的低能Ar 注入酿酒酵母Ke-y,筛选出了一种较好的菌体保护液,获得了一系列Ar 注入参数。在该研究体系内,Ar 最佳注入剂量分别为9 0×1015 ions/cm2 或13 5×1015 ions/cm2(适于IBB Device 1 型离子注入机)和1 0×1016ions/cm2 或1 4×1016 ions/cm2(适于LZD1000型离子注入机),为离子束介导外源基因组DNA在酵母菌Ke-y中的遗传转化奠定了基础。     

离子注入花生四烯酸产生菌诱变选育

利用离子束注入生物技术对花生四烯酸产生菌(Mortierella alpina)进行诱变高产菌筛选。筛选到高产菌I₄₉N₁₈,该菌每升培养液可得生物量30.80g(约4%的含水量),干菌体油脂含量为25.8%,其中花生四烯酸的含量占总.脂的45.37%。30L和250L发酵罐发酵试验,该高产菌的花生.四烯酸得率为4.0g/L。     

Tight junction biogenesis during early development

The tight junction (TJ) is an essential component of the differentiated epithelial cell required for polarised transport and intercellular integrity and signalling. Whilst much can be learnt about how the TJ is constructed and maintained and how it functions using a wide range of cellular systems, the mechanisms of TJ biogenesis within developmental models must be studied to gain insight into this process as an integral part of epithelial differentiation. Here, we review TJ biogenesis in the early mammalian embryo, mainly considering the mouse but also including the human and other species, and, briefly, within the amphibian embryo. We relate TJ biogenesis to inherent mechanisms of cell differentiation and biosynthesis occurring during cleavage of the egg and the formation of the first epithelium. We also evaluate a wide range of exogenous cues, including cell-cell interactions, protein kinase C signalling, gap junctional communication, Na⁺/K⁺-ATPase and cellular energy status, that may contribute to TJ biogenesis in the embryo and how these may shape the pattern of early morphogenesis.     

Immunohistochemical localization of prostaglandin H synthase in the embryo and uterus of the mouse from ovulation through implantation

Prostaglandins (PGs) in the embryo and endometrium are involved in processes that are important for implantation. Although the presence of PGs (PGE2, PGF2 alpha, PGI2) in decidualized endometrium has been widely reported, less is known about the capacity of the pre-implantation embryo to synthesize PGs. Prostaglandin H (PGH) synthase is necessary for the production of PGs. Using an immunohistochemical method, PGH synthase was localized in the mouse embryo and uterus from superovulation through embryo implantation. No PGH synthase was detected in oocytes at the time of ovulation or in single-cell embryos 1 day post-fertilization (PF). Circular areas of immunostaining became evident in the cytoplasm of blastomeres at the morula stage (day 3 PF). After implantation (day 5 PF), a low level of PGH synthase reactivity was observed in embryonic cells; no PGH synthase was detected in the embryo by day 7 PF. The endometrial glands exhibited maximal immunostaining by day 3 PF, and after implantation, PGH synthase appeared in decidual cells along the border of placentation. Low levels of PGH synthase reactivity were detected in myometrial cells during the period after superovulation through day 7 PF. This is the first demonstration of PGH synthase in the mouse embryo prior to apposition with glandular endometrial epithelium, supporting the hypothesis that the embryo has the potential to produce PGs that may mediate autocrine and/or paracrine responses at the time of nidation.     

Dynamic distribution of epidermal growth factor during mouse embryo peri-implantation

Embryo implantation depends on the synchronized development of the blastocyst and the endometrium. This process is highly controlled by the coordinated action of the steroid hormones: estrogen and progesterone. By autocrine, paracrine or juxtacrine routes, some growth factors or cytokines are involved in this steroidal regulation pathway. Here we report the effects of epidermal growth factor (EGF) on embryo implantation in the mouse, the expression and distribution patterns of EGF protein in the mouse blastocyst, ectoplacental cone (EPC) and peri-implantation uterus on days 1-8 of gestation.By RT-PCR and dot blot, we found that EGF and its receptor (EGFR) are co-expressed in the blastocyst and peri-implantational uteri of pregnant days 2-8 (D2-D8) mice. Injection of EGF antibody into a uterine horn on the third day of pregnancy (D3) significantly reduced the number of mouse embryos that implanted on D8, indicating EGF have a function in the mouse embryo implantation.Further investigation by using indirect immunofluorescence and confocal microscope was made to trace EGF and EGFR protein localization during the mouse embryo implantation. EGF and EGFR are co-localized in the blastocyst, and in the secondary trophoblastic giant cells (SGC) of the EPC. At the pre-implantation stage, the distribution of EGF protein in the mouse uterus changes from epithelium to stroma. On D1 of pregnancy, EGF is mainly distributed in uterine stroma and myometrium. On D2, it is present in the uterine epithelium. On D3, it changes again from the uterine epithelium to the stroma. By D4, EGF is predominantly in the stroma. This dynamic distribution correlates with the proliferation activity of uterine cells at each period. On D6-D8 of embryo implantation, EGF 3 protein accumulates at the uterine mesometrial pole, a region that contributes to the trophoblastic invasiveness and placentation.This temporal and spatial localization of EGF protein in the mouse uterus implicates the cytokine in the regulation of trophoblastic invasiveness and uterine receptiveness.     

离子注入对微生物细胞的刻蚀与对DNA的损伤及修复

以耐辐射异常球菌为试材,以E. coli 为对照,用显微扫描电镜和3H-TdR标记,研究了离子注入对微生物细胞的刻蚀与对DNA的损伤及其修复。结果表明,注入离子对细胞存在着刻蚀损伤;中性蔗糖梯度密度离心沉降分析证明, 大剂量下离子注入可直接导致DNA损伤,并观察到在对应的存活率峰值注入剂量下,D. radiodurans修复损伤DNA的能力比E. coli 强,还证明了细胞经不同时间温育后,损伤的DNA分子得到了部分修复。 Abstract：　The direct action of N+implantationin on D. radioduransand E. coliwas investigated by SEM, and their cells were labeled with 3H-TdR, which were implanted by 20keV N+after incubation 18hours, then the DNA of lysed cells was subjected to the neutral sucrose gradient(5%～20%) ultra-centrifugation sedimentation analysis. The results showed that N+implantation exerted direct action on two kinds of microorganisms; the momentum transfer and energy deposition of implantation ions produced the direct etching damage on cells, and repair DNA efficiency of D.radiodurans was higher than that of E. coli. Meanwhile, the damaged DNA incomplete repairing was observed. When incubation was continued up to 6 hours, the rejoined DNA molecules broke again. The repair of damaged DNA could be inhibited by 200μg/ml chloramphenicol. This suggested that DNA damage was serious by ion implantation and damaged DNA repair of cells need continuously synthesizing repair enzyme.     

听力障碍青少年治疗过程心理干预对患儿语言能力恢复和心境状态的影响

摘要 目的：探讨听力障碍青少年治疗过程心理干预对患儿语言能力恢复和心境状态的影响。方法：选取我院2019年6月到2020年6月共收治的80例7~18岁听力障碍青少年作为研究对象,将患儿随机分为观察组与对照组,每组40例。对所有患儿应用人工耳蜗植入术进行治疗,给予对照组常规言语训练以及健康教育等干预。观察组患儿在常规干预基础上增加全治疗过程的心理干预。对比两组患儿的治疗效果,语言能力恢复,心境状态,ABC评分。结果：观察组患儿治疗的总有效率为92.50%,对照组患儿治疗的总有效率为75.00%,观察组高于对照组（P＜0.05）;两组患儿干预前的言语形成、听觉能力以及听觉感知对比无明显差异（P＞0.05）,两组患儿通过治疗与干预之后,言语形成、听觉能力以及听觉感知明显提升,且观察组评分高于对照组（P＜0.05）;两组患儿干预前的精神、控制、能力、忍受消极情感以及接受变化对比无明显差异（P＞0.05）,两组患儿通过治疗与干预之后,精神、控制、能力、忍受消极情感以及接受变化明显降低,且观察组评分低于对照组（P＜0.05）;两组干预前的兴奋、易激怒、刻板行为以及不恰当语言等评分比较无统计学意义（P＞0.05）,两组患儿干预后,各评分均下降,其中观察组小于对照组,差异有统计学意义（P＜0.05）。结论：对听力障碍青少年在常规治疗与干预基础上增加心理干预,能够提升患儿的治疗效果,提升语言能力恢复情况,减少负面情绪,提升患儿的心境状态,值得临床应用推广。