[PreS1 Antigen of HBV Down-Regulates MHC-â on the Surface of Hepatocytes and Promotes Hepatocarcinogenesis].

Objective: To explore the internal mechanism of hepatocellular carcinoma (HCC) induced by chronic hepatitis B virus (HBV) infection. Methods: L02, HepG2 and Huh7 cells stably overexpressing HBV preS1 antigen were analyzed by flow cytometry, qRT-PCR and tumorigenesis in nude mice to evaluate the effect of preS1 antigen in HBV-related hepatocarcinogenesis. Results: Our results showed that the expression of cancer stem cell (CSCs) related factors and cell surface markers in preS1 overexpressing cells were up-regulated, and the tumorigenicity of these cells was enhanced in nude mice. In addition, preS1 overexpression could down-regulate the expression of major histocompatibility complex Ⅰ (MHC-Ⅰ). The expression of MHC-Ⅰ on the cell surface could be restored by adding interferon gamma (IFN-γ) in the process of cell culturing and the tumorigenicity of cells in nude mice could thus be reduced. Conclusion: Based on the above results, we believe that preS1 is a carcinogen of HBV and that it promotes the formation of liver cancer through down regulating MHC-Ⅰ on the surface of hepatocytes.

[Analysis of non-bacterial respiratory pathogen infection in children with asthmatic diseases].

OBJECTIVE: To investigate the association of non-bacterial respiratory pathogens with asthmatic diseases in children, and the clinical significance of total serum IgE levels and peripheral eosinophil count in infection with non-bacterial respiratory pathogens. METHODS: Indirect immunofluorescence assay was used to detect IgM antibodies against nine types of non-bacterial respiratory pathogens in the sera of 490 children with asthmatic diseases between September 2010 and September 2011. Pathogens were analyzed and total serum IgE levels and peripheral eosinophil count were measured in IgM-positive cases. RESULTS: Of the 490 children with asthmatic diseases, 47.6% (233 cases) were positive with IgM antibodies against non-bacterial respiratory pathogens, the most common being Mycoplasma pneumoniae (MP) (25.3%), followed by adenovirus (ADV) (8.9%) and influenza B virus (Flu B) (8.8%). Thirty-six cases suffered from co-infection of two or more non-bacterial pathogens, mainly comprising MP and other pathogens (94%). There were significant differences in the total detection rate of IgM antibodies among all age groups (0-30 days: 50.0%; 1-6 months: 67.3%; 0.5-1 year: 33.1%; 1-3 years: 57.3%; 3-8.9 years: 61.7%). The positive rate of IgM antibodies against respiratory pathogens was highest in children with bronchial asthma, followed by children with asthmatic bronchitis, and it was lowest in children with bronchiolitis. IgM-positive children had significantly decreased blood eosinophils and significantly increased total serum IgE levels. CONCLUSIONS: The main non-bacterial respiratory pathogens include MP, ADV and Flu B in children with asthmatic diseases, and co-infection of MP and other non-bacterial pathogens is common. Infants aged 1 to 6 months have a higher infection rate than other age groups. Monitoring the changes in total serum IgE levels and peripheral eosinophil count has great significance for the clinical diagnosis and treatment of asthmatic diseases in children.

[The application of proton magnetic resonance spectroscopy and computerized tomography in evaluating nonalcoholic fatty liver disease].

OBJECTIVE: To investigate the application of proton magnetic resonance spectroscopy (1HMRS) and computerized tomography (CT) in evaluating nonalcoholic fatty liver disease (NAFLD). METHODS: Twenty-two NAFLD patients were selected, according to the Chinese Medical Association standard, and compared with 20 healthy persons (as the control group). Their body mass index (BMI), waist to hip ratio (WHR), and blood pressure (BP) were examined. The serum ALT, the concentration of fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG), and uric acid (UA) were tested simultaneously. The severity of hepatosteatosis was evaluated by 1HMRS and CT scans of their livers. The intrahepatic content of lipid (IHCL) and CT liver and spleen ratios were measured. RESULTS: The BMI, WHR, serum ALT, FBG, TG, and UA were all elevated significantly in the NAFLD group and were (28.4+/-2.4) kg/m2, 0.91+/-0.04, (71.5+/-24.8) U/L, (5.67+/-0.61) mmol/L, (2.48+/-1.46) mmol/L, (420.7+/-57.5)micromol/L, respectively, P less than 0.01 or 0.05. Meanwhile, in the NAFLD group, the IHCL calculated by 1HMRS were increased and CT value ratios were decreased significantly compared with those of the control group (27.49%+/-12.27% vs 1.34%+/-0.79%, P less than 0.01). However, there was no correlation between the clinical features and the IHCL and between the clinical features and CT value ratios, but a negative correlation existed in the CT value ratio and IHCL. CONCLUSIONS: The intrahepatic content of lipids can be measured precisely by 1HMRS, and 1HMRS is better than CT in quantitative evaluations of NAFLD.