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Aims: The aim of this study was to classify Edwardsiella strains isolated from China aquaculture based on biochemical and molecular methods. Methods and Results: In this study, biochemical characterization of 19 Edwardsiella tarda isolates and two Edwardsiella ictaluri isolates was performed with API 20E system. Other pathogenicity-related phenotypes such as haemagglutination, haemolytic activities and lethality to fish were also examined in these strains. As it was difficult to categorize the subgroups of Edw. tarda according to their origins or phenotypic properties, three PCR-based methods, i.e. PCR amplification of virulence genes, Enterobacterial repetitive intergenic consensus-PCR and BOX-PCR, were carried out to further resolve the relatedness of the Edw. tarda isolates. As a result, all Edw. tarda isolates could be generally grouped into pathogenic and nonpathogenic branches before being classified into strain-specific or origin-specific clades. Conclusions: Biochemical characterization was sensitive for interspecific typing, while PCR-based approaches permitted a more accurate discrimination for intraspecific typing resulting in pathogenic and nonpathogenic clusters and further more delicate clades for Edwardsiella. Significance and Impact of the Study: PCR-based genomic fingerprinting to study the relatedness and trace the pathogenicity of the Edwardsiella strains will be helpful in investigating the virulence factors of Edwardsiella and in the development of vaccines and diagnostics for edwardsiellosis. [ABSTRACT FROM AUTHOR]

Background There are racial differences in the prevalence and types of androgenetic alopecia (AGA). The prevalence of AGA has been studied in Caucasians and in some Asian people. In China, although there have been some epidemiological studies carried out in single cities or regions, no multicentre population-based study has been reported. Objectives To study the prevalence and types of AGA in China and to compare the results with those previously reported in Caucasians and in other Asian people. Methods A community-based study was carried out in six cities of China. Subjects were interviewed face-to-face and completed questionnaires. The degree of AGA was classified according to the Norwood and Ludwig classifications. Results In total 17 886 subjects were interviewed and 15 257 completed the questionnaires. In men, the overall prevalence of AGA was 21·3%, with 2·8% in men aged 18–29 years, 13·3% in those aged 30–39 years, 21·4% in those aged 40–49 years, 31·9% in those aged 50–59 years, 36·2% in those aged 60–69 years and 41·4% in those aged 70 years and over. The most common type was frontal and vertex hair loss. A small number of subjects (3·7%) showed ‘female pattern’ hair loss. In women, the prevalence of AGA was 6·0%, with 1·3% in women aged 18–29 years, 2·3% in those aged 30–39 years, 5·4% in those aged 40–49 years, 7·5% in those aged 50–59 years, 10·3% in those aged 60–69 years and 11·8% in those aged 70 years and over. Ludwig grade I was the most common type. The prevalence of AGA varied between cities. A positive family history was present in 29·7% of men and 19·2% of women with AGA. Conclusions The prevalence of AGA in Chinese men and women was lower than in Caucasians and similar to that in Koreans. [ABSTRACT FROM AUTHOR]

HBs antigen (HBsAg)183–191 (FLLTRILTI, R187 peptide) is a dominant human leucocyte antigen-A2 (HLA-A2)-restricted epitope associated with hepatitis B virus (HBV) infection in Caucasian populations. However, its prevalence is poorly understood in China, where there is a high incidence of HBV infection. In this report, we sequenced the region of HBsAg derived from 103 Chinese patients. Approximately 16·5% of the patients bore a mutant HBsAg183–191 epitope in which the original arginine (R187) was substituted with a lysine (K187 mutant peptide). Importantly, K187 still bound to HLA-A2 with high affinity, and elicited specific cytotoxic T lymphocyte (CTL) responses in HLA-A2/Kb transgenic mice. K187-specific CTLs were also generated successfully in acute hepatitis B (AHB) patients, indicating that this mutant epitope is processed and presented effectively. Our findings show that R187-specific CTLs can cross-react with the K187 peptide. These findings reveal that K187 still has the property of an HLA-A2 restricted epitope, and elicits a protective anti-HBV CTL response in humans. [ABSTRACT FROM AUTHOR]

P and S receiver functions obtained from a portable array of 34 broad-band stations in east central China provide a detailed image of the crust–mantle and lithosphere–asthenosphere boundaries (LAB) in the Dabie Shan and its adjacent areas. Clear S-to- P converted waves produced at the LAB show a thin lithosphere beneath the whole study area. Based on our results, the thickest lithosphere of 72 km is observed beneath the southern part of the area within the Yangtze craton, whereas beneath the North-China platform, the lithosphere is only 60 km thick. S receiver functions also reveal, in good agreement with P receiver functions, a maximum depth of the Moho beneath the Dabie Shan orogen at approximately 40 km. Furthermore, we interpret the structural difference at 32° latitude as the probable location of the mantle suture formed between the Yangtze and the Sino-Korean cratons. [ABSTRACT FROM AUTHOR]