AIM: To investigate whether human umbilical vein endothelial cells and human atherosclerotic plaque lesions can coexpress CD40 and CD40 ligand . METHODS: The expression of CD40 and its ligand CD40L on human endothelia cells were measured by fluorescence microscope , flow cytometry(FCM), reverse transcription PCR(RT-PCR) and Western blotting, respectively. Both CD40 and CD40L expression in atheroma plaques were determined by immunohistochemistry. RESULTS: Cultured human endothelial cells constitutively coexpressed CD40 and CD40L in mRNA and protein levels. Stimulation with interleukin-1?, interleukin-6, tumor necrosis factor-? and interferon-? increased expression of CD40 and CD40L on endothelial cells . Human atherosclerotic lesions( n =6) showed coexpression of immunoreactive CD40 and CD40L. However, no expression of CD40 and CD40L in nonatherosclerotic human arteries. CD40L mainly expressed on the shoulder and base of the plaque. But CD40 was widespreadly expressed in plaque. CONCLUSION: Our results demonstrated that CD40 and CD40L coexpressed on human umbilical vein endothelial cells and in human atherosclerotic plaque lesions. These findings suggest a previously unsuspected role for CD40-CD40L interactions in atherosclerosis.

Objective: To establish p53 trancated muteins group and analyse their expression and effects on p53 related downstream genes in HeLa cells. Methods: Using PCR-based site-directed mutagenesis technique, a group of P53 muteins with the N- and/or C-terminals differently trancated were set up. The plasmids with p53 mutein genes were used to transfect HeLa cells, the p53 muteins and some p53 related downstream genes' expression were analyzed by RT-PCR. Results: The p53 muteins were expressed in HeLa cells and they had effects on some of p53 related downstream genes. Conclusion: The P53 muteins may be a good tool to analyze P53 function and has effects on p53 related downstream genes' expression model.

AIM: To investigate the mechanism underlying insulin-stimulated increase in glucose uptake during low-flow myocardial ischemia. METHODS: The expression of myocardial GLUT1 polypeptide was determined by semiquantitative immunoblotting. The expression of GLUT1 mRNA was determined by semiquantitative Northern blotting. RESULTS: After infusing insulin during low- flow myocardial ischemia for 8 h,the expression of both GLUT1 mRNA and GLUT1 polypeptide was significantly higher in experimental myocardium than that in normal myocardium. The glucose uptake was upregulated at the same time in the exprimental myocardium. CONCLUSION: Insulin enhances the expression of GLUT1 mRNA and GLUT1 polypeptide in ischemic myocardial regions. GLUT1 expression may be an important mechanism by which myocardial cells enhance glucose uptake and metabolism during low-flow myocardial ischemia. [