大天鹅睾丸和附睾的组织结构及EGF,Bax,Bcl-2蛋白和iNOS的表达

为了解大天鹅(Cygnus cygnus)睾丸和附睾的组织结构特征及相关活性物质的表达情况,用生物显微技术观察了大天鹅睾丸和附睾的组织结构,用免疫组织化学方法检测了EGF,Bax蛋白,Bcl-2蛋白和iNOS在睾丸和附睾中的表达.结果表明,大天鹅睾丸内生精小管主要由支持细胞和各级生精细胞构成,众多生精小管被睾丸间质隔开;附睾由输出小管和附睾管组成;大天鹅睾丸生精小管直径、生殖细胞大小、附睾管直径及上皮厚度等与其他脊椎动物存在差异;EGF,Bax蛋白,Bcl-2蛋白在睾丸生精小管管周的肌样细胞、精原细胞、精母细胞、精子细胞、间质细胞和附睾管上皮细胞等处呈免疫反应阳性;iNOS在睾丸间质内的血管壁及间质细胞、附睾管上皮细胞、附睾结缔组织等处有阳性表达;EGF可能参与其精子发生、获能及激素生成的调控过程;Bax蛋白和Bcl-2蛋白可能共同参与调控正常大天鹅睾丸和附睾细胞的凋亡;iNOS可能也参与雄性大天鹅各种生殖活动的调节.     

表皮生长因子间接竞争酶联免疫吸附测定法的建立

目的：建立一种可应用于临床的快速定量测定表皮生长因子含量的酶联免疫吸附测定法(ELISA)。方法：以重组人表皮生长因子(ECF)为包被抗原和竞争抗原,两与一定量的ECF。抗血清反应,建立检测EGF的间接竞争ELISA方法。结果：理想的包被抗原质量浓度为1μg/mL,ECF抗血清的工作浓度为1：10000,酶标二抗工作浓度为1：3000,可测最适范围为0．5～16ng／mL,最小检测量为0．5ng/mL,批内和批间变异系数分别为6．21％和7．42％。得到回归方程y=-13．65ln(x) 81．554,相关系数R^2=0．997。结论：建立了快速定量检测ECF的间接竞争ELISA方法。     

表皮生长因子对猕猴胚胎角膜上皮组织增殖效应的研究

离体培养试验表明，小鼠颌下腺表此生长因子对离体培养猕猴胚胎眼角膜上皮组织具有显著促进细胞增殖和分化的效应。培养４ｄ的实验组角膜上皮的厚度，上皮细胞增殖层烽以及上皮组织中基底层细胞核与表层细胞核两者的比率均较正常猴胚角膜增长３倍。与此同时培养４ｄ的实验组角膜上皮厚度和上皮细胞的层数，都达到成年猴正常角膜上皮的结构水平。     

体外培养时间和表皮生长因子对牦牛卵母细胞成熟及孤雌胚胎体外发育的影响

研究在成熟液中添加表皮生长因子（Epidermal growth factor,EGF）以及成熟时间对牦牛卵母细胞体外成熟及孤雌胚胎体外发育的影响,以确立牦牛卵母细胞体外成熟的最佳体系.结果表明,成熟液中添加EGF组的成熟率明显高于未添加组（P＜0.05）,并且牦牛卵母细胞的成熟率随着EGF添加的浓度增加也不断上升;随着体外培养时间的延长,成熟率逐渐增加,培养24 h后成熟率趋于稳定;胚胎体外培养液中添加EGF能显著提高孤雌胚胎的8-细胞和囊胚形成率（P＜0.05）.由此推测：在体外培养22-24 h,且添加40 μg/mL EGF最有利于牦牛卵母细胞体外成熟;胚胎培养液中添加40μg/mLEGF能显著提高牦牛孤雌胚胎的体外发育能力.     

Effect of epidermal growth factor on growth and maturation of fetal and neonatal rat small intestine in organ culture

Summary Small intestinal explants from pre- and post-natal rats were incubated in an organ culture system in the absence and presence of epidermal growth factor (EGF). The rate of synthesis of small intestinal DNA and protein as well as the activity of lactase and alkaline phosphatase increased rapidly between 17 and 20-day gestational age, whereafter they declined. The maximal incorporation of³H-thymidine and¹⁴C-alanine into DNA and protein, respectively, was significantly stimulated by EGF (100 ng/ml). EGF had no effect on the activity of either lactase or alkaline phosphatase in the small intestinal explants.Acknowledgment. The project was supported by grants from the Veterans Administration Research Service. The authors wish to thank Dr. M. C. Geokas, Chief, Department of Medicine, Veterans Administration Medical Center, Martinez, CA, for providing us with excellent laboratory facilities and for his encouragement in this study.     

Transgenic and knock-out mice for deciphering the roles of EGFR ligands

Generation of genetically engineered mice with either gain-of-function or loss-of-function mutations is the most popular technique for determining gene functions and the interrelationship between molecules in vivo. These models have provided a wealth of information about the developmental and physiological roles of oncogenes and growth factors. To date, transgenic techniques have been used extensively to study the functions of the epidermal growth factor (EGF) family. This review highlights some of the major recent findings pertinent to the EGF receptor (EGFR) and its ligands with special reference to elucidating how EGF and its related growth factors work together to regulate reproduction, growth and development. Finally, future investigations on ligand-ligand communications, EGFR and its ligands in neural stem cell research, and the mechanisms of EGFR signaling and trafficking in cells are also suggested. Received 24 May 2002; received after revision 15 July 2002; accepted 16 July 2002     

Effects of anti-EGF serum on newborn mice

Summary Administration of anti-EGF serum to newborn mice led to delay of eyelid opening and incisor tooth eruption, acceleration of hair growth and delay of weight gain. These results indicate that in the first week after birth EGF still has a physiological function, which can be abrogated by anti-EGF serum.     

新生小鼠神经干细胞的分离、培养和鉴定

目的：探讨新生小鼠神经干细胞(NSCs)分离、培养以及鉴定的方法。方法：分离新生昆明种小鼠(出生24h内)的大脑组织,经胰酶消化加机械吹打后,利用无血清培养基悬浮培养细胞,获得具有自我增殖能力的细胞克隆,并将细胞克隆贴壁培养测其分化能力。应用抗Ncstin、Musashi、SSEA-1、NSE免疫细胞化学方法及BrdU标记方法鉴定细胞克隆。结果：从新生昆明种小鼠大脑组织分离的细胞悬液,经悬浮培养,生成大量具有增殖能力的细胞,可形成神经球(neurosphercs),抗Nestin、Musashi、SSEA-1阳性,BrdU标记也呈阳性。细胞克隆贴壁培养后神经球分化为神经细胞,抗NSE阳性。结论：上述方法分离的细胞具有自我更新、自我复制及分化为神经细胞的能力,属于中枢神经系统干细胞。     

GST—EGF融合蛋白在大肠杆菌中的表达与纯化

将小鼠ＥＧＦ基因克隆至谷胱甘肽Ｓ－转移酶（ＧＳＴ）融合表达载体ｐＧＥＸ－２Ｔ,转化大肠杆菌ＤＨ５α,获得高效表达,融合蛋白ＧＳＴ－ｍＥＧＦ经Ｓｅｐｈａｒｏｓｅ４Ｂ－ＧＳＨ亲和层析柱纯化和凝血酶消化获得有免疫活性的ｍＥＧＦ,表明ＧＳＴ融合基因表达系统不仅能提高表达产物的稳定性也有利于产物的纯化