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1.
PLoS One ; 5(2): e9297, 2010 Feb 19.
Article in English | MEDLINE | ID: mdl-20174575

ABSTRACT

A novel hepatitis B virus (HBV) strain (W29) was isolated from serum samples in the northwest of China. Phylogenetic and distance analyses indicate that this strain is grouped with a series of distinct strains discovered in Vietnam and Laos that have been proposed to be a new genotype I. TreeOrderScan and GroupScan methods were used to study the intergenotype recombination of this special group. Recombination plots and tree maps of W29 and these putative genotype I strains exhibit distinct characteristics that are unexpected in typical genotype C strains of HBV. The amino acids of P gene, S gene, X gene, and C gene of all genotypes (including subtypes) were compared, and eight unique sites were found in genotype I. In vitro and in vivo experiments were also conducted to determine phenotypic characteristics between W29 and other representative strains of different genotypes obtained from China. Secretion of HBsAg in Huh7 cells is uniformly abundant among genotypes A, B, C, and I (W29), but not genotype D. HBeAg secretion is low in genotype I (W29), whose level is close to genotype A and much lower than genotypes B, C, and D. Results from the acute hydrodynamic injection mouse model also exhibit a similar pattern. From an overview of the results, the viral markers of W29 (I1) in Huh7 cells and mice had a more similar level to genotype A than genotype C, although the latter was closer to W29 in distance analysis. All evidence suggests that W29, together with other related strains found in Vietnam and Laos, should be classified into a new genotype.


Subject(s)
DNA, Viral/genetics , Hepatitis B virus/genetics , Hepatitis B/virology , Phylogeny , Amino Acid Sequence , Animals , Cell Line, Tumor , China , DNA, Viral/chemistry , Genotype , Hepatitis B/blood , Hepatitis B Core Antigens/blood , Hepatitis B Core Antigens/metabolism , Hepatitis B Surface Antigens/blood , Hepatitis B Surface Antigens/metabolism , Hepatitis B e Antigens/blood , Hepatitis B e Antigens/metabolism , Hepatitis B virus/classification , Hepatitis B virus/immunology , Humans , Laos , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Vietnam
2.
J Clin Microbiol ; 48(2): 357-62, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19940057

ABSTRACT

The characteristics of 30 carriers with occult hepatitis B virus (HBV) infection (OBI) were compared with those of 30 individuals diagnosed as being HBV carriers at the time of blood donation, 60 asymptomatic carriers, and 60 chronic hepatitis patients. The prevalence of genotype C was significantly higher in carriers with OBIs than in any other HBsAg-positive (HBsAg(+)) group (P < 0.001). Specific amino acid substitutions in the regions from amino acids 117 to 121 and amino acids 144 to 147 located in the major hydrophilic region of the S gene were associated with carriers with OBIs (P < 0.01 for carriers with OBIs versus HBsAg(+) donors, carriers with OBIs versus HBsAg(+) asymptomatic carriers, and carriers with OBIs versus HBsAg(+) chronic hepatitis patients). G145R was the major variation in the HBV isolates responsible for local occult HBV infections.


Subject(s)
Blood Donors , Carrier State/virology , Hepatitis B virus/genetics , Hepatitis B virus/isolation & purification , Hepatitis B/virology , Adult , Amino Acid Sequence , Amino Acid Substitution , China , DNA, Viral/genetics , Female , Genotype , Hepatitis B Surface Antigens/genetics , Hepatitis B, Chronic/virology , Humans , Male , Molecular Sequence Data , Mutation, Missense , Sequence Analysis, DNA , Young Adult
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2577-80, 2009 Sep.
Article in Chinese | MEDLINE | ID: mdl-19950680

ABSTRACT

A problem of higher background value and lower measured Cd value exists when Cd is digested by conventional dry digestion method, measured by graphite furnace atomic absorption, and calculated with peak height numeration. This problem results in difficulty for evaluating samples with Cd contents in the neighborhood of critical values. In order to solve the problem, the present paper focused on background measurement with graphite furnace atomic absorption, modified the pre-preparation procedures of the traditional method, and screened the optimal concentration of the modifier. Results showed that addition of Mg (NO3)2 as a modifier into the samples before incineration was preferred. It could not only yield a clear solution but also reduce its background by ten times, considerably eliminating background interference. In addition, using 3% HNO3 in stead of 1 mol x L(-1) HCl as dilution for the incinerated sample could eliminate the background. The improved methods could acquire a zero concentration of measurement for the blank, re-correct the values measured by graphite furnace atomic absorption and obtain more reliable results.

4.
Bing Du Xue Bao ; 25(3): 178-84, 2009 May.
Article in Chinese | MEDLINE | ID: mdl-19634759

ABSTRACT

Occult hepatitis B virus (HBV) infection status of blood donors in a southern city in China was investigated by immunological assays and nucleic acid testing. Overall, 17 (0.19%, 95% CI: 0.11%-0.30%) of the 9023 HBsAg negative samples were found to be positive for the presence of HBV DNA. "A" epitope sequences were obtained from 14 among them. Mutation(s) in aa124-aa147 existed in 6 (42.9%, 6/14) samples and 4 (66.7%, 4/6)were G145R mutation. Ratio of genotype C in occult donors (10/17) was statistically higher than HBs-positive donors (0/15, P<0.01), which implied that HBV genotype C leaded to occult infection more easily.


Subject(s)
Blood Donors , Hepatitis B Surface Antigens/immunology , Hepatitis B virus/physiology , Hepatitis B/epidemiology , Adolescent , Adult , China/epidemiology , DNA, Viral/genetics , Female , Genotype , Hepatitis B/immunology , Hepatitis B/virology , Hepatitis B Surface Antigens/genetics , Hepatitis B virus/classification , Hepatitis B virus/genetics , Hepatitis B virus/immunology , Humans , Immunologic Tests , Male , Mutation , Sequence Alignment , Sequence Analysis, DNA , Young Adult
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