绵羊的背部、耳部和腹股沟部的毛发性状、生长速度存在差异,背部毛发弯曲、细长、密度高、生长速度快,耳部、腹股沟部毛发粗直、密度低、生长速度慢。研究表明,EDA/EDAR、IGFBP5/Krox20、WNT等介导的信号通路及毛发角蛋白基因对毛发纤...绵羊的背部、耳部和腹股沟部的毛发性状、生长速度存在差异,背部毛发弯曲、细长、密度高、生长速度快,耳部、腹股沟部毛发粗直、密度低、生长速度慢。研究表明,EDA/EDAR、IGFBP5/Krox20、WNT等介导的信号通路及毛发角蛋白基因对毛发纤维弯曲的形成有重要的影响。本研究利用实时荧光定量PCR、原位杂交技术、Western印迹和免疫组织化学等技术,对外异蛋白受体(ectodysplasin A receptor,EDAR)在绵羊背部、耳部和腹股沟皮肤中的m RNA、蛋白质表达水平和定位进行研究,以探讨EDAR与绵羊毛发的生长和性状的关系。实时荧光定量PCR结果显示,EDAR在绵羊背部皮肤中相对基因表达量是绵羊腹股沟皮肤的4.9倍(P<0.01),耳部是腹股沟部的1.4倍(P<0.05),背部是耳部的3.4倍(P<0.05);原位杂交和免疫组化结果表明,EDAR基因m RNA和蛋白质在背部、耳部和腹股沟部毛囊均有表达。根据光密度值可知,背部表达量最高,耳部次之,而腹股沟部最低;Western印迹结果显示,绵羊皮肤组织蛋白质提取物中存在与兔抗EDAR多克隆抗体发生免疫阳性反应的蛋白条带,绵羊皮肤背部平均蛋白质表达量最高,耳部次之,而腹股沟部最低,差异极显著(P<0.01)。研究结果提示,EDAR可能参与绵羊毛发卷曲的形成和调控,对毛发密度、生长速度等可能也有影响。展开更多
Current proposed mechanisms implicate both early and latent Epstein-Barr virus(EBV)infection in the carcinogenic cascade,whereas epidemiological studies have always associated nasopharyngeal carcinoma(NPC)with early c...Current proposed mechanisms implicate both early and latent Epstein-Barr virus(EBV)infection in the carcinogenic cascade,whereas epidemiological studies have always associated nasopharyngeal carcinoma(NPC)with early childhood EBV infection and with chronic ear,nose,and sinus conditions.Moreover,most patients with NPC present with IgA antibody titers to EBV capsid antigen(VCA-lgA),which can precede actual tumor presentation by several years.If early childhood EBV infection indeed constitutes a key event in NPC carcinogenesis,one would have to explain the inability to detect the virus in normal nasopharyngeal epithelium of patients at a high risk for EBV infection.It is perhaps possible that EBV resides within the salivary glands,instead of the epithelium,during latency.This claim is indirectly supported by observations that the East Asian phenotype shares the characteristics of an increased susceptibility to NPC and immature salivary gland morphogenesis,the latter of which is influenced by the association of salivary gland morphogenesis with an evolutionary variant of the human ectodysplasin receptor gene(EDAR),EDARV370A.Whether the immature salivary gland represents a more favorable nidus for EBV is uncertain,but in patients with infectious mononucleosis,EBV has been isolated in this anatomical organ.The presence of EBV-induced lymphoepitheliomas in the salivary glands and lungs further addresses the possibility of submucosal spread of the virus.Adding to the fact that the fossa of Rosen Muller contains a transformative zone active only in the first decade of life,one might be tempted to speculate the possibility of an alternative carcinogenic cascade for NPC that is perhaps not dissimilar to the model of human papillomavirus and cervical cancer.展开更多
文摘绵羊的背部、耳部和腹股沟部的毛发性状、生长速度存在差异,背部毛发弯曲、细长、密度高、生长速度快,耳部、腹股沟部毛发粗直、密度低、生长速度慢。研究表明,EDA/EDAR、IGFBP5/Krox20、WNT等介导的信号通路及毛发角蛋白基因对毛发纤维弯曲的形成有重要的影响。本研究利用实时荧光定量PCR、原位杂交技术、Western印迹和免疫组织化学等技术,对外异蛋白受体(ectodysplasin A receptor,EDAR)在绵羊背部、耳部和腹股沟皮肤中的m RNA、蛋白质表达水平和定位进行研究,以探讨EDAR与绵羊毛发的生长和性状的关系。实时荧光定量PCR结果显示,EDAR在绵羊背部皮肤中相对基因表达量是绵羊腹股沟皮肤的4.9倍(P<0.01),耳部是腹股沟部的1.4倍(P<0.05),背部是耳部的3.4倍(P<0.05);原位杂交和免疫组化结果表明,EDAR基因m RNA和蛋白质在背部、耳部和腹股沟部毛囊均有表达。根据光密度值可知,背部表达量最高,耳部次之,而腹股沟部最低;Western印迹结果显示,绵羊皮肤组织蛋白质提取物中存在与兔抗EDAR多克隆抗体发生免疫阳性反应的蛋白条带,绵羊皮肤背部平均蛋白质表达量最高,耳部次之,而腹股沟部最低,差异极显著(P<0.01)。研究结果提示,EDAR可能参与绵羊毛发卷曲的形成和调控,对毛发密度、生长速度等可能也有影响。
文摘Current proposed mechanisms implicate both early and latent Epstein-Barr virus(EBV)infection in the carcinogenic cascade,whereas epidemiological studies have always associated nasopharyngeal carcinoma(NPC)with early childhood EBV infection and with chronic ear,nose,and sinus conditions.Moreover,most patients with NPC present with IgA antibody titers to EBV capsid antigen(VCA-lgA),which can precede actual tumor presentation by several years.If early childhood EBV infection indeed constitutes a key event in NPC carcinogenesis,one would have to explain the inability to detect the virus in normal nasopharyngeal epithelium of patients at a high risk for EBV infection.It is perhaps possible that EBV resides within the salivary glands,instead of the epithelium,during latency.This claim is indirectly supported by observations that the East Asian phenotype shares the characteristics of an increased susceptibility to NPC and immature salivary gland morphogenesis,the latter of which is influenced by the association of salivary gland morphogenesis with an evolutionary variant of the human ectodysplasin receptor gene(EDAR),EDARV370A.Whether the immature salivary gland represents a more favorable nidus for EBV is uncertain,but in patients with infectious mononucleosis,EBV has been isolated in this anatomical organ.The presence of EBV-induced lymphoepitheliomas in the salivary glands and lungs further addresses the possibility of submucosal spread of the virus.Adding to the fact that the fossa of Rosen Muller contains a transformative zone active only in the first decade of life,one might be tempted to speculate the possibility of an alternative carcinogenic cascade for NPC that is perhaps not dissimilar to the model of human papillomavirus and cervical cancer.
