Objective To evaluate the accuracy and value of ventricular function in conotruncal defects(CTD)by three-dimensional echocardiography(3DE).Methods Fifty-two children with CTD and forty-three children with normal hearts were examined by 3DE.The measurements of left ventricular volume and wall mass were outlined and calculated.The measurements of left ventricular volume and wall mass of 3DE in preoperative CTD were compared with those of 2D biplane Simpson-method in preoperative CTD,3DE in control group and 2D biplane Simpson-method in control group.The results of 3DE and 2DE preoperative measurements were also compared with their postoperative clinical cardiac conditions.Results From the findings of analysis of variance and Student-Newman-Keuls(SNK)test,there was no significant difference between 3DE and 2DE measurements of left ventricular function in normal children,but there was significant difference between 3DE and 2DE measurements of left ventricular function in children with CTD.2DE measurements of left ventricular volume and wall mass in the CTD group were significant underestimated and less correlated with their postoperative clinical cardiac conditions(r=0.20,P=0.2086)than 3DE measurements(r=0.39,P=0.0090).Furthermore,left ventricular function in the CTD group was poorer than that in the control group.Stroke volume and effective function were reduced due to increasing end-systolic volume.while left ventricular wall mass was increased due to the possible compensation of its ventricular muscle.With the lower end-diastolic volume,stroke volume and effective function,patients were more likely to have the occurrence of postoperative low cardiac output.Conclusions By making a precise quantitative assessment,3DE is very useful in providing more information for preoperative diagnosis in CTD and predicting such postoperative prognoses as the occurrence of postoperative low cardiac output.

OBJECTIVETo investigate the roles of Domain I and Domain II of hepatitis C virus (HCV) 5' untranslated region (UTR) in the translation initiation activity of HCV 5'UTR in different host cell lines.

METHODSThe eukaryotic expression plasmid pCMVNCRLuc (pCN1), in which full-length HCV 5'UTR regulates firefly luciferase expression, was modified by deleting Domain I and the downstream single-stranded sequence (43 bp in total) from the UTR (pCNl-d2), Domain I with the downstream single-stranded sequence and Domain II (118 bp in total) from the UTR (pCNl-d3), or the total UTR (pCNl-d5). The modified plasmids were transfected via liposome into different cell lines with pRL-TK plasmid co-transfected as the normalization control. At 36 h after the transfection, the total cellular RNA was harvested for semi-quantitative RT-PCR, and the relative expression activities of luciferase were assayed with a dual luciferase reporter gene assay system. The translation initiation activities of the truncated HCV 5'UTRs in different translation systems were analyzed.

RESULTSDeletion of Domain I and the downstream single-stranded sequence caused no significant changes of the translational activity of HCV 5'UTR in Hela or C6 cells, but decreased the translational activity by 46% in L-02 cells and increased the translational activity by 46% in 293T cells. Deletion of both Domain I and Domain II resulted in decreased translational activity of HCV 5'UTR by 51% in HeLa cells, but increased the translational activity by 40% in L-02 cells, 60% in C6 cells and 135% in 293T cells.

CONCLUSIONSDomain I and Domain II of HCV 5'UTR perform cell type-specific roles in HCV IRES-driven translation initiation.

5' Untranslated Regions ; Genes, Reporter ; HeLa Cells ; Hepacivirus ; genetics ; Humans ; Luciferases ; Plasmids ; Protein Biosynthesis ; genetics ; RNA, Viral ; genetics ; Transfection