母胎细胞转运与乙型肝炎病毒宫内感染关系的研究

目的探讨母胎细胞转运与乙型肝炎病毒(HBV)宫内感染的关系。方法用STRPCR、As-PCR及hemi-nPCR技术扩增HBsAg阳性孕妇及其新生儿外周血中胎儿DNA及母亲DNA，通过检测TH01、GSTM1、ACE等位基因确定母．胎细胞转运与胎．母细胞转运。采用巢式病例对照研究方法分析母-胎细胞转运与HBV宫内感染的关系。结果以GSTM1、ACE基因多态性判定母亲源性或胎儿源性等位基因，42对信息病例中有26例新生儿发生了母．胎细胞转运(61．90％，26／42)；40对信息病例中有32例发生了胎-母细胞转运(80．00％，32／40)；10对母胎发生了双向转运。统计分析显示母-胎细胞转运与HBV宫内感染有关联，胎．母细胞转运与HBV宫内感染无关联，母-胎细胞转运与胎-母细胞转运无关。母-胎细胞转运、孕妇PBMC HBV DNA阳性是HBV宫内感染的危险因素，二者未显示交互作用；母-胎细胞转运、孕妇PBMC HBV DNA阳性与新生儿PBMC HBV感染有关，两因素间亦未显示交互作用。结论母胎之间存在细胞转运，母-胎细胞转运是HBV宫内感染的危险因素，这可能是对HBV宫内感染途径的补充。  

The nutrition-immunity-infection nexis: The enumeration and functional assessment of lymphocyte subsets in nutritional deficiency

Clinical, epidemiologic and pathological evidence suggests that nutritional deficiency impairs host resistance to infection. Changes in immunocompetence occur early in the course of nutritional depletion and may well precede growth failure and overt expression of disease. Cell-mediated immunity is depressed. Undernourished individuals have reduced number of rosette-forming T lymphocytes. There is a significant reduction in the proportion of T4+ helper cells and in their ability to provide help to B cells in mitogen-induced antibody production. The ratio of T4:T8 cells is reduced. Low serum thymic factor activity and increased leukocyte terminal deoxynucleotidyl transferase levels suggest faulty terminal differentiation of T cells. Increased lympholysis may also occur, in part as a result of elevated cortisol levels. The migration of labelled lymph node cells to the intestine is reduced. These changes in the number and function of lymphocyte subsets may explain the impaired cell-mediated immunocompetence in protein-energy malnutrition and other nutritional deficiency states.