I labelled T. gondii parasites were injected via tail vein into 14 day pregnant mouse( Kunming strain). Radioactive tracings of fetal train and pathologic changes were studiet. The results revealed that infection rat...I labelled T. gondii parasites were injected via tail vein into 14 day pregnant mouse( Kunming strain). Radioactive tracings of fetal train and pathologic changes were studiet. The results revealed that infection rates in the pregnant mice and in their fetal heads were 30.60% and 71.2% respectively. The ratio of the radioactivity between the fetal heads and the fetal trunks was 1.32-5.95 , being directly proportional to the durations of infection. Autoradiographs of light and electron microscopy indicated that the parasites appeared in the neurogliocytes of the fetal mice as early as 4 8 h post infection, and might be seen in the nucleus 48h after infection with degeneration and rupture of the cells. Numbers of the cranial nerve cells was distinctively reduced at 72h post infection. This study thus provided the experimental pathology evidence for the development of fetal neural malformation and cerebral lesions from T. gondil infected dam mouse.展开更多
Kinetics of thymocyte development in vivo during embryogenesis was pursued. The early development of thymocytes in the fetal and neonatal BALB/c mice was discontinuous, with four waves of cell proliferation occurring ...Kinetics of thymocyte development in vivo during embryogenesis was pursued. The early development of thymocytes in the fetal and neonatal BALB/c mice was discontinuous, with four waves of cell proliferation occurring at fetal day (Fd) 14 to 17, Fd 18 to day (D) 1 after birth, D 2 to D 5 and D6 thereafter. The first three proliferation waves coincided with the generation of CD4hiCD8hi (DP), TCR+CD4hiCD8-/lo (CD4 SP), and TCR+CD4-/loCD8int/hi(CD8 SP) thymocytes, respectively. The transition from DN to DP cells was further investigated and it was found out that there were two differential pathways via immature single positive (ISP) cells in the BALB/c mice, each functioning at different fetal ages. One is via TCR-CD4-CD8+ cells, occurring between Fd 15 and Fd 17 and the other is via TCR-CD4+CD8- ceils,occurring from Fd 17 until birth. In contrast, the TCR-CD4-CD8+ pathway dominated overwhelmingly in the C57BL/6 mice. These findings shed new light on the hypothesis that the differential pathway preference varies with mouse strains. With respect to the shift in the intensity of CD4 and CD8 expression on thymocytes from fetal to adult mice, the TCR+CD4hiCD8-/lo, and TCR+CD4-/loCD8int/hi subsets might be equivalent to the medullary type TCR+CD4/CD8 SP cells.展开更多
经孕鼠尾静脉注射弓形虫 NT 强毒株滋养体孵育液后分批处死,观察胎鼠脑动态病理变化。结果表明,胎鼠脑病变主要为神经细胞变性、坏死、数量减少,胶质细胞明显增生。孕鼠感染后2小时,免疫组化即可在胎鼠脑组织内发现弓形虫。提示,先天性...经孕鼠尾静脉注射弓形虫 NT 强毒株滋养体孵育液后分批处死,观察胎鼠脑动态病理变化。结果表明,胎鼠脑病变主要为神经细胞变性、坏死、数量减少,胶质细胞明显增生。孕鼠感染后2小时,免疫组化即可在胎鼠脑组织内发现弓形虫。提示,先天性弓形虫感染的新生儿出现的中枢神经系统发育异常,是由于弓形虫对大脑神经细胞的损害所致;免疫组化显示组织、细胞内的弓形虫是一个简便、准确的诊断方法。展开更多
文摘I labelled T. gondii parasites were injected via tail vein into 14 day pregnant mouse( Kunming strain). Radioactive tracings of fetal train and pathologic changes were studiet. The results revealed that infection rates in the pregnant mice and in their fetal heads were 30.60% and 71.2% respectively. The ratio of the radioactivity between the fetal heads and the fetal trunks was 1.32-5.95 , being directly proportional to the durations of infection. Autoradiographs of light and electron microscopy indicated that the parasites appeared in the neurogliocytes of the fetal mice as early as 4 8 h post infection, and might be seen in the nucleus 48h after infection with degeneration and rupture of the cells. Numbers of the cranial nerve cells was distinctively reduced at 72h post infection. This study thus provided the experimental pathology evidence for the development of fetal neural malformation and cerebral lesions from T. gondil infected dam mouse.
基金supported by grants from National 973 Program in China(No.G1999053904)National Natural Sciences Foundation of China(No.39730410)
文摘Kinetics of thymocyte development in vivo during embryogenesis was pursued. The early development of thymocytes in the fetal and neonatal BALB/c mice was discontinuous, with four waves of cell proliferation occurring at fetal day (Fd) 14 to 17, Fd 18 to day (D) 1 after birth, D 2 to D 5 and D6 thereafter. The first three proliferation waves coincided with the generation of CD4hiCD8hi (DP), TCR+CD4hiCD8-/lo (CD4 SP), and TCR+CD4-/loCD8int/hi(CD8 SP) thymocytes, respectively. The transition from DN to DP cells was further investigated and it was found out that there were two differential pathways via immature single positive (ISP) cells in the BALB/c mice, each functioning at different fetal ages. One is via TCR-CD4-CD8+ cells, occurring between Fd 15 and Fd 17 and the other is via TCR-CD4+CD8- ceils,occurring from Fd 17 until birth. In contrast, the TCR-CD4-CD8+ pathway dominated overwhelmingly in the C57BL/6 mice. These findings shed new light on the hypothesis that the differential pathway preference varies with mouse strains. With respect to the shift in the intensity of CD4 and CD8 expression on thymocytes from fetal to adult mice, the TCR+CD4hiCD8-/lo, and TCR+CD4-/loCD8int/hi subsets might be equivalent to the medullary type TCR+CD4/CD8 SP cells.
文摘经孕鼠尾静脉注射弓形虫 NT 强毒株滋养体孵育液后分批处死,观察胎鼠脑动态病理变化。结果表明,胎鼠脑病变主要为神经细胞变性、坏死、数量减少,胶质细胞明显增生。孕鼠感染后2小时,免疫组化即可在胎鼠脑组织内发现弓形虫。提示,先天性弓形虫感染的新生儿出现的中枢神经系统发育异常,是由于弓形虫对大脑神经细胞的损害所致;免疫组化显示组织、细胞内的弓形虫是一个简便、准确的诊断方法。
基金SupportedbyScienceandTechnologyFoundationofGuangdongProvince (No .99M01204G),ScienceandTechnologyFoundationofGuangzhoucity (No .2 0 01-2-037-01),andKeyScienceFoundationofGuangdongProvince (No .0 2 1195 )
