Effect of soybean protein in lowering human serum cholesterol / 中国组织工程研究

ABSTRACT

BACKGROUND: Although we have gained much information about leadinduced organ damage, the effect of blood lead level on T cell subgroup is yet to be determined.OBJECTIVE: To assess the effect of blood lead level on T cell subgroup of children, and the association of T cell subgroup with threshold limit value of blood lead level.DESIGN: Comparative observation.SETTING: The Institute of Molecular Microorganism, Maternity and Child Care Hospital, Shanxi Provincial Children Hospital.PARTICIPANTS: Sixty children, (32 boys and 28 girls), aged 3-6 years with a mean of (4.5±1.5) years old, were selected from the suburbs of Taiyuan city between May 2003 and October 2003. Informed consents were obtained from all their guardians. The enrolled children according to their blood lead levels were assigned into three groups, 13 in Group Ⅰ with blood lead level ≥ 0.48 μmol/L, 20 in Group 2 with lead level ≥ 0.24 μmol/L but ＜ 0.48 μmoL/L and 27 in Group 3 with lead level ＜ 0.24 μmol/L.METHODS: Blood lead level and expression of T cell subgroup were measured with graphite furnace atomic absorption spectroscopy and immunofluorescence methods respectively. Student t test was used in data analysis, and linear correlation analysis was used to assess the correlation between blood lead level and expression of T cell subgroup.level and expression of T cell subgroup.pression of CD3 and ratio of CD4 to CD8 were lower in Group 1 (lead level ≥0.48 μmol/L) than Group 3 (lead level ＜ 0.24 μmol/L) (t=3.27,blood lead level showed had significant inverse correlation with CD3 expression and the ratio of CD4 to CD8(r=-0.689,-0.674,P ＜ 0.01).CONCLUSION: A blood lead level ≥ 0.48 μmol/L, is shown to significantly decrease the expression of CD3 and ratio of CD4 to CD8 in peripheral blood, which may impair the children's immunological function.