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The aim of our study was to determine the distribution of hepatitis B virus (HBV) genotypes and subgenotypes in ethnic minorities in Yunnan province to provide evidence supporting the theoretical basis for hepatitis B prevention and control. We obtained serum samples and demographic data from 765 individuals reported by Yunnan province who had either acute or chronic HBV infection and were from one of 20 ethnic minority populations: Achang, Bai, Brown, Tibetan, Dai, Deang, Dulong, Hani, Hui, Jingpo, Lahu, Yi, Lisu Miao, Naxi, Nu, Pumi, Wa, Yao, or Zhuang people. We sequenced the HBV DNA and determined the genotypes and subgenotypes of the isolated HBVs. We mapped the genotype and subgenotype distribution by ethnic minority population and conducted descriptive analyses. There were four genotypes among the 20 ethnic groups: genotype B (21.3% of samples), C (76.6%), D (1.8%) and I (0.3%). The most common subgenotype was C1. There were no genotype differences by gender (P = 0.954) or age (P = 0.274), but there were differences by region (P < 0.001). There were differences in genotype distribution (P < 0.001) and subgenotype distribution (P = 0.011) by ethnic group. Genotype D was most prominent in Tibet and most HBV isolates were C/D recombinant viruses. The only two genotype I virus isolates were in Zhuang people. Susceptibility and geographic patterns may influence HBV prevalence in different ethnic populations, but additional research is needed for such a determination. [ABSTRACT FROM AUTHOR]

In this study, mechanical properties and deformation mechanisms of Mg-Gd-Y-Zr alloy at temperatures ranging from 77 K to 523 K have been investigated. The effects of temperature on the mechanical properties, deformation mechanism, and fracture mechanism are discussed. The results show that the strengths of alloy decrease gradually while the elongations increase progressively with increasing temperature. The maximum ultimate tensile strength of the alloy as high as 442 MPa is obtained at 77 K. As the temperature increases from 77 K to 523 K, the ultimate tensile strength of the alloy decreases from 442 MPa to 254 MPa and the elongations increase from 6.3% to 28.9% gradually. The study verifies that the deformation at 77 K is predominated by basal slip and $${{\left\{ {10\bar{1}2} \right\}} \mathord{\left/ {\vphantom {{\left\{ {10\bar{1}2} \right\}} {\left\langle {10\bar{1}1} \right\rangle }}} \right. \kern-0pt} {\left\langle {10\bar{1}1} \right\rangle }}$$ deformation twinning system. At 223 K, lots of twins emerge primarily at grain boundaries. At 373 K, all dislocations are proved to be 〈 a〉 dislocations. At 523 K, although basal slip is still the dominant deformation mechanism, non-basal slip systems also become activate. [ABSTRACT FROM AUTHOR]

The aim of our study was to determine the distribution of hepatitis B virus (HBV) genotypes and subgenotypes in ethnic minorities in Yunnan province to provide evidence supporting the theoretical basis for hepatitis B prevention and control. We obtained serum samples and demographic data from 765 individuals reported by Yunnan province who had either acute or chronic HBV infection and were from one of 20 ethnic minority populations: Achang, Bai, Brown, Tibetan, Dai, Deang, Dulong, Hani, Hui, Jingpo, Lahu, Yi, Lisu Miao, Naxi, Nu, Pumi, Wa, Yao, or Zhuang people. We sequenced the HBV DNA and determined the genotypes and subgenotypes of the isolated HBVs. We mapped the genotype and subgenotype distribution by ethnic minority population and conducted descriptive analyses. There were four genotypes among the 20 ethnic groups: genotype B (21.3% of samples), C (76.6%), D (1.8%) and I (0.3%). The most common subgenotype was C1. There were no genotype differences by gender (P = 0.954) or age (P = 0.274), but there were differences by region (P < 0.001). There were differences in genotype distribution (P < 0.001) and subgenotype distribution (P = 0.011) by ethnic group. Genotype D was most prominent in Tibet and most HBV isolates were C/D recombinant viruses. The only two genotype I virus isolates were in Zhuang people. Susceptibility and geographic patterns may influence HBV prevalence in different ethnic populations, but additional research is needed for such a determination.

To investigate the epidemic and evolutionary trends of enterovirus (EV) in the external environment of Yunnan Province, China, molecular typing was performed on 4 EV strains that were isolated from environmental sewage in Yunnan. The VP1 region of isolates was amplified by RT-PCR using universal enterovirus primers, and the amplified VP1 region was sequenced for GenBank BLAST search and genotype analysis. The 4 EV strains were identified as ECHO7. Their nucleotide and amino acid homologies with the VP1 sequences of 68 ECHO7 strains retrieved from GenBank were measured by Mega software analysis. Our findings showed that ECHO7 strains from environmental sewage and population samples were in different evolutionary branches. These strains showed typical geographical and temporal differences; In addition, there were different transmission chains at the same time and in the same area. ECHO7 strains isolated from sewage water and patients with acute flaccid paralysis during the same period in Yunnan belonged to different clusters and evolved at different speeds. Special concerns are needed for this problem. Continuous molecular biological surveillance of human EV in the external environment of Yunnan will provide strong support for early warning of EV diseases.

In order to explore the genotype distribution and molecular evolution of non-polio enterovirus (NPEVs)in Yunnan Province,the People's Republic of China, we sequenced and analyzed the partial VP1 coding region of 105 NPEVs isolated from acute flaccid paralysis (AFP) surveillance in Yunnan province during a 5- year study period from 2006 to 2010. The viral genomes of 105 NPEVs were translated to corresponding amino acid sequences and compared with those of the prototype strains, and the phylogenetic tree was constructed among these VP1 nucleotide sequences and other prototype strains from GenBank. Analysis showed that 18 isolates were classified into 7 serotypes of human enterovirus A species, while 77 isolates into 22 serotypes of B and 10 isolates into 4 serotypes of C species. However, we did not isolate any viruses which belonged to human enterovirus D species. Thus, under AFP surveillance, human enterovirus B species accounted for 73. 3% of the 105 isolates and was considered as the predominant one,followed by human enterovirus A(17. 1%) and human enterovirus C(9. 5%). Phylogenetic analysis showed that various serotypes of the virus and the corresponding prototype strains or other representative strains clustered into the same grooup, however, Yunnan strains and prototype strains were located in the different branches (except CA2,EV90 and EV76). The degree of variation was different even among the same genotype strains. This report showed that different genotype strains spread widely in Yunnan Province.

To explore the enteroviruses surveillance among healthy children under 15 years old in the border areas of Yunnan Province and Myanmar in 2009. The stool samples were collected from the healthy children under 15 years old who came from the border areas of Myanmar and Yunnan Province, virus isolation and sequencing were conducted for all the 271 samples. 6 strains of polioviruses (PVs) were detected from 271 stools with an isolation rate of 2.8%, which belonged to vaccine strains and 24 non-polioviruses (NPVs) were detected with an isolation rate of 8.9%. 24 NPVs belonged to human enterovirus group B (HEV-B) with 6 serotypes, HEV-A, HEV-C and HEV-D viruses were not isolated. Among them, 13 NPVs were E7 (54.17%) and 5 NPVs were E13 (20.83%). Our results showed that the enterovirus carrying rate in the border areas of Yunnan province was higher than the rate of routine acute flaccid paralysis (AFP) detection system. The HEV-B viruses were the only enteroviruses isolated. The phylogenetical analysis showed that Echovirus 7(E7) and 13 (E13) exhibited genetic polymorphism.

Molecular typing was conducted according to the reported method for one HBsAg positive carrier who had a physical examination in Yunnan Province. The S gene of this HBV sample was amplified by nested PCR and the PCR products were directly sequenced. Blast searching was done on the Genbank database and the sequence were compared with the HBV reference sequences in database. The phylogenetic tree was constructed. Homology analysis of nucleotide and smino acid were performed between the sequences from the sample and the reference sequences corresponding to HBV genotype A to I. Analysis of nucleotide and amino acid identities suggested that the sample belonged to HBV genotype I. The HBV genotype I is the first reported in China.

Objective: To know genotypes and serotypes of hepatitis B virus (HBV) detected from hepatitis B infected people in Yunnan Province., Methods: Serum samples were collected from HBsAg carriers detected from people who had a physical examination at Yunnan Provincial Center for Disease Control and Prevention. The S genes of HBV were amplified by nested PCR and the PCR products were sequenced. The viral genotype was identified by phylogenetic analysis. 27 reference sequences corresponding to HBV genotype A to I were obtained from GenBank. According to the amino acid sequences deduced from the nucleotide sequences of S gene, the dominant serotype of HBV detected from these people were confirmed., Results: 39 HBsAg positive serum samples were detected from 2216 people who had a physical examination. The results shows that 76.9% were C genotype; 15.4% were B genotype; 5.1% were D genotype; 2.5% were I genotype. Three serotypes were found. The rates of adw2, adrq+ and ayr serotypes are 71.8%, 17.9% and 10.3% respectively. All of adw2 subtype specimens are C genotype. Among the serum specimens in which both HBsAg and HBeAg are positive, 75% were C genotype and adw2 subtype., Conclusion: It is determined that the main genotype and subtype of HBV prevailed in Yunnan province is C genotype and adw2 subtype.

Objective: To explore the enterovirus infection status among healthy children under 15 years old in the border areas of Yunnan province that connecting Myanmar., Methods: A total of 319 stool samples were collected from healthy children in the 10 entrance ports. Enterovirus was isolated from these stool samples and then poliovirus and adenovirus were serotyped by neutralization test using specific anti-sera. All the non-polio enteroviruses (NPEVs) were identified by partial sequencing of VP1 gene., Results: All 53 enterovirus were isolated from 319 stool samples and 16.6% of them carried the virus. 23 polio virus (PVs) and 30 NPEVs were isolated with rates of carrying the virus were 7.2% and 9.4% respectively. 4 adenovirus were also isolated with a rate as 1.25%. 1 isolate could not be amplified by any Pan-enterovirus primers or by RT-PCR so was not able to be sequenced. The results of NPEVs sequencing showed that:1 isolate (3.3%) was classified into 1 serotype of HEV-A while 20 isolates (66.7%) were classified into 11 serotypes of HEV-B and 8 isolates (26.7%) were classified into 3 serotypes of HEV-C. However, we could not isolate any viruses that belong to HEV-D. nt. Result from the aa identify calculation showed that the nt and aa identification between isolates and corresponding standard strains were more than 75% and 85% respectively. The findings were similar to the international standards., Conclusion: Our results showed that the rate of carrying the enterovirus especially poliovirus in some areas of Yunnan province that bordering Myanmar was higher than that of rate through the routine acute flaccid paralysis detection system. Of the enterovirus isolated, HEV-B group appeared the predominant with the wide spread of enterovirus serotype. Some newer enterovirus were also detected such as EV73 (2 strains), EV75 (1 strain), EV80 (1 strain) and EV96 (4 strains).

Molecular typing was conducted according to the reported methods for 2 enteroviruses that were isolated from healthy children in the border areas of Yunnan Province with Myanmar. RT-PCR and sequencing were performed with 292/222 primers according to the Oberste's methods. The resulting sequences were blasted against the Genbank database and compared with all available enterovirus database. Analysis of homology at nucleotide and amino acid level identically suggested that the two enteroviruses are human enterovirus 73.

Objective: To highlight the clinical features and diagnosis of chronic disseminated tuberculosis, with emphasizing the usefulness of several recently available diagnostic technologies in this setting., Method: We presented a case of chronic disseminated tuberculosis diagnosed with the combined application of interferon-gamma release assay T-SPOT. TB, 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET), and gene chip assay., Results: A 53-year-old gentleman who had chronic cough for 7 years and fever for 2 weeks was referred to our hospital for further evaluation. 18F-FDG-PET/CT scan showed increased FDG uptake in multiple lesions involving bilateral lungs, supraclavicular, mediastinal and intro-abdominal lymph nodes and bones, mimicking metastatic malignancy. T-SPOT. TB assay revealed significant responses [ early secreting antigen target 6 (ESAT-6): 3 908 spot forming cells (SFCs)/10(6) peripheral blood mononuclear cells (PBMCs), culture filtrate protein (CFP-10): 3 400 SFCs/10(6) PBMCs]. Subsequent biopsy of supraclavicular lymph node, lung, and ilium revealed granulomas, while culture of the obtained tissue yeilded mycobacteria. Gene chip testing identified M. tuberculosis sensitive to isoniazid and rifampin. After 10 weeks of treatment for tuberculosis, the patient's condition was improved and a second T-SPOT. TB assay showed significantly reduced responses (ESAT-6: 1528 SFCs/10(6) PBMCs; CFP-10: 1460 SFCs/10(6) PBMCs)., Conclusions: Timely diagnosis of chronic disseminated tuberculosis requires high index of suspicion. T-SPOT. TB assay, PET/CT, and gene chip assay may provide valuable information that facilitates further diagnostic procedures and treatment decision.

Objective: To study the association between the polymorphisms of vitamin D receptor (VDR) gene and autoimmune liver diseases and (AIH) and primary biliary cirrhosis (PBC) in Chinese., Methods: PCR-RELP was used to investigate the polymorphisms in exon 2, and exon 7 to exon 9 of VDR among 49 AIH patients, 58 PBC patients, and 160 healthy controls, all Chinese. VDR polymorphisms were assessed by FokI, BsmI, ApaI, and TaqI endonucleases restriction fragment length polymorphism analysis after specific polymerase chain reaction (PCR) amplification., Results: The distribution of VDR gene polymorphism in Chinese was similar to those in Koreans and Japanese, and different from those in the Germans and Spaniards. The percentage of ff phenotype carriers was significantly higher in the AIH patients than in the healthy controls (34.7% vs. 48.1%, chi(2) = 5.47, P = 0.019) and the percentage of Ff phenotype carriers was lower in the AIH patients than in the healthy controls (34.7% vs. 48.1%, P = 0.057). The percentage of Bb phenotype carriers was significantly lower in the PBC patients than in the healthy controls (5.2% vs. 17.5%, P = 0.021) and. the percentage of bb phenotype carriers was significantly higher in the PBC patients than in the healthy controls (94.8% vs. 80.6%, chi(2) = 6.52, P = 0.01). We also detected a significant association of the BsmI polymorphisms in PBC patients in comparison with controls (P = 0.01). Furthermore we found the difference in the FokI, BsmI, ApaI, and TaqI genotype distribution between Chinese health controls and Caucasian health controls., Conclusion: There is a significant association between FokI polymorphism and AIH and a significant association between the BsmI polymorphisms and PBC in Chinese.