Dongping Xu

Guilin Medical University, Ling-ch’uan, Guangxi Zhuangzu Zizhiqu, China

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Publications (30)149.66 Total impact

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    ABSTRACT: The study aimed to clarify whether rtN236V mutation of hepatitis B virus (HBV) derived from adefovir dipivoxil (ADV)-refractory patients was associated with the drug resistance. A total of 18,419 patients from Beijing 302 Hospital were investigated. HBV complete reverse-transcriptase region of polymerase was screened by direct sequencing and verified by clonal sequencing if necessary. Replication-competent wild-type and mutant HBV genomic amplicons were constructed, transfected into HepG2 cells and cultured in the presence or absence of serially-diluted nucleos(t)ide analogs. Intracellular HBV replicative intermediates were quantitated for calculating the 50% effective concentration of drug (EC50). rtN236V was detected in six ADV-refractory patients; signature ADV-resistant mutations rtA181V and rtN236T were detected in 1,311 patients. rtN236V mutants emerged predominantly with virologic breakthrough in clinical course of the six patients. Phenotypic analysis of the mutants from two patients was performed. rtN236V mutants from patient 1 and patient 2 exhibited 3.90-fold and 3.10-fold decreased susceptibility to ADV respectively compared to the wild-type virus; by contrast, rtN236T mutants from the patients had 4.50-fold and 4.75-fold decreased susceptibility respectively. Both mutants had a relatively lower viral replication capacity compared to wild-type virus in the absence of antivirals and remained susceptible to lamivudine, entecavir and tenofovir disoproxil fumarate. In clinical practice, switching-to entecavir rescue therapy suppressed HBV DNA to an undetectable level and normalized alanine aminotransferase level for both patients. rtN236V was a novel infrequently-occurred ADV-resistance-associated mutation. It conferred a moderate resistance to ADV with relatively lower natural replication capacity.
    Antiviral therapy 04/2014; · 3.07 Impact Factor
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    ABSTRACT: Hepatitis B virus (HBV) genotypes and subgenotypes may vary in geographical distribution and virological features. Previous investigations, including ours, showed that HBV genotypes B and C were respectively predominant in South and North China, while genotypes A and D were infrequently detected and genotype G was not found. In this study, a novel A/C/G intergenotype was identified in patients with chronic HBV infection in Guilin, a city in southern China. Initial phylogenetic analysis based on the S gene suggested the HBV recombinant to be genotype G. However, extended genotyping based on the entire HBV genome indicated it to be an A/C/G intergenotype with a closer relation to genotype C. Breakpoint analysis using the SIMPLOT program revealed that the recombinant had a recombination with a arrangement of genotypes A, G, A and C fragments. Compared with the HBV recombinants harboring one or two genotype G fragments found in Asian countries, this Guilin recombinant was highly similar to the Vietnam (98-99%) and Long An recombinants (96-99%), but had a relatively low similarity to the Thailand one (89%). Unlike those with the typical genotype G of HBV, the patients with the Guilin recombinant were seropositive for HBeAg. Moreover, a relatively high HBV DNA viral load (>2×10(6) IU/ml) was detected in the patients, and the analysis of viral replication capacity showed that the Guilin recombinant strains had a competent replication capacity similar to genotypes B and C strains. These findings can aid in not only the clarification of the phylogenetic origin of the HBV recombinants with the genotype G fragment found in Asian countries, but also the understanding of the virological properties of these complicated HBV recombinants.
    PLoS ONE 01/2014; 9(1):e84005. · 3.73 Impact Factor
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    ABSTRACT: This study aimed to investigate the relationships of intrahepatic cccDNA with serum HBsAg and with HBV DNA in treatment-naive patients throughout acute and chronic HBV infection. A total of 120 patients who had a liver biopsy were enrolled, including 19 with acute hepatitis B (AHB), and 101 patients with chronic HBV infection (CHB) of whom were 10 in immune-tolerant (IT) phase, 59 in immune-clearance (IC) phase, 8 in low-replicative (LR) phase, and 24 in HBeAg-negative hepatitis (ENH) phase. Intrahepatic cccDNA, serum HBsAg and serum HBV DNA levels were comparatively analyzed. The median intrahepatic cccDNA levels were 0.18 4.80, 3.81, 0.22 and 0.97 copies/cell for patients with AHB, CHB-IT, CHB-IC, CHB-LR, and CHB-ENH, respectively. In AHB patients, intrahepatic cccDNA was positively correlated with serum HBsAg (r = 0.665, P = 0.003), as well as serum HBV DNA (r = 0.536, P = 0.022). In CHB patients, intrahepatic cccDNA was positively correlated with serum HBsAg in the IC phase (r = 0.392, P = 0.005), and with serum HBV DNA in the IC phase (r = 0.301, P = 0.036) and ENH phase (r = 0.588, P = 0.013). HBV replicative efficiency, defined as the ratio of serum HBV DNA to intrahepatic cccDNA, was obviously lower in AHB and CHB-LR patients than in CHB-IT, CHB-IC and CHB-ENH patients (0.70 and 0.53 vs. 1.12, 1.09 and 0.99, P<0.001, values were logarithmic transformed for analysis). In CHB-IC patients, HBV replicative efficiency was positively correlated with histological activity index of liver inflammation (r = 0.308, P = 0.009). Serum HBsAg and HBV DNA levels may reflect the amount of active intrahepatic cccDNA in treatment-naive AHB and CHB-IC patients. Reduced intrahepatic cccDNA and HBV replicative efficiency may imply effective immune control of HBV infection.
    PLoS ONE 01/2014; 9(2):e89046. · 3.73 Impact Factor
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    ABSTRACT: Lamivudine (LAM) is still widely used for anti-HBV therapy in China. The study aimed to clarify whether a newly-found rtM204Q mutation from patients was associated with the drug resistance. HBV complete reverse-transcriptase region was screened by direct sequencing and verified by clonal sequencing. Replication-competent plasmids containing patient-derived 1.1mer mutant or wild-type viral genome were constructed and transfected into HepG2 cells. After cultured with or without serially-diluted antiviral drugs, intracellular HBV replicative intermediates were quantitated for calculating the 50% effective concentration of drug (EC50). A total of 12,000 serum samples of 9,830 patients with chronic HBV infection were screened. rtM204Q mutation was detected in seven LAM-refractory patients. By contrast, rtM204I/rtM204V mutations were detected in 2,502 patients' samples. The rtM204Q emerged either alone or in concomitance with rtM204I/rtM204V, and all were accompanied with virologic breakthrough in clinical course. Clonal sequencing verified that rtM204Q mutant was predominant in viral quasispecies of these samples. Phenotypic analysis showed that rtM204Q mutant had 89.9% of replication capacity and 76-fold increased LAM EC50 of the concomitant wild-type strain. By contrast, rtM204I mutant in the sample had lower replication capacity and higher LAM resistance (46.3% and 1396-fold increased LAM EC50 of the wild-type strain) compared to rtM204Q mutant. rtM204Q mutant was susceptible to adefovir dipivoxil (ADV) in vitro and ADV/ADV+LAM rescue therapy in clinic. rtM204Q is suggested to be a novel LAM-resistance-associated mutation. It conferred a moderate resistance with higher competent natural replication capacity compared to rtM204I mutation.
    PLoS ONE 01/2014; 9(2):e89015. · 3.73 Impact Factor
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    ABSTRACT: This study investigated features and clinical implications of HBV mutations in patients with different clinical manifestations. In total, 516 patients were enrolled in this study, including 131 patients with acute hepatitis B, 239 patients with chronic hepatitis B, and 146 patients with acute-on-chronic liver failure. HBV genotypes and mutations were analyzed by direct sequencing of complete viral genomes. Genotypes B2, C1, C2, and D1 accounted for 22.2%, 1.6%, 74.6%, and 1.6%, respectively. Genotype B was more frequently detected in patients with acute hepatitis B than those with chronic hepatitis B and acute-on-chronic liver failure. Deletion mutations were detected mostly in preS1 and preS2 regions and the detection rates were 3.8%, 19.7%, and 24.7% for acute hepatitis B, chronic hepatitis B and acute-on-chronic liver failure patients, respectively. Incidences of point mutation T53C (preS1F53L), G1613A (polR841K), G1775A and A1762T + G1764A in the basal core promoter region, G1896A and G1899A in precore region and A2189C (coreI97L) in core region increased along with acute hepatitis B, chronic hepatitis B, and acute-on-chronic liver failure. The mutation G1896A was independently associated with poor survival of patients with acute-on-chronic liver failure. The gradual increase of viral mutation incidences was also observed in three HLA-A2-restricted cytotoxic T lymphocyte epitopes from HLA-A2-positive patients, that is env188-196 (5.8%, 10.1%, 22.5%), core107-115 (4.3%, 4.6%, 19.7%), and x92-100 (1.4%, 20.2%, 33.8%). In conclusion, certain viral mutations in various regions of HBV genome are associated with disease progression of HBV infection. J. Med. Virol. © 2013 Wiley Periodicals, Inc.
    Journal of Medical Virology 07/2013; · 2.37 Impact Factor
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    ABSTRACT: Objective To express T lymphocyte receptors (TCRs) on hepatitis B virus (HBV)-specific cytotoxic T lymphocytes (CTLs) mediated by retrovirus and investigate their binding affinity. Methods Peripheral blood mononuclear cells were isolated from acute hepatitis B patients with HLA-A2(+); phenotype, and after induced, HBV-specific CTLs were sorted out followed by cloning and proliferating. Cell RNAs were extracted. The sequences of TCR's α and β chains were obtained by means of RT-PCR, 5'RACE and OVER-LAP PCR, for constructing TCR retrovirus vectors. Through retrovirus-mediated transduction, HBV-specific TCRs were expressed on Jurkat cells and CD8(+); T cells from HLA-A2(+); healthy subjects. ResultsTwo paired TCR Vα and Vβ, respectively named α21β13 and α15β13, were obtained from one patient with acute hepatitis B and HLA-A2(+);. The titers of packaged recombinant retroviruses were 1.5×10(5);-5.0×10(5); IU/mL. Immunofluorescence staining by anti-Vβ13 TCR-PE targeting the specific TCR and HLA-A2 restricted epitope-specific pentamer showed a positive expression of reconstructed TCR on T cells. The positive cells accounted for 1.06%-2.25% for Vβ13 on Jurkat cells, 1.03%-2.06% for Vβ13 chain and 1.05%-1.12% for the epitope-specific pentamer on T cells from healthy HLA-A2(+); subjects respectively. By contrast, only less than 0.05% cells from healthy HLA-A2(-); subjects were positive for either Vβ13 or the pentamer. Conclusion TCRs on HBV-specific CTLs could be expressed by TCR gene transfer mediated by retrovirus, and they were proved with binding affinity to HLA-A2-restricted epitope.
    Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 05/2013; 29(5):453-7.
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    ABSTRACT: Interferon-gamma induced protein 10 (IP-10) was suggested to be involved in liver injury in viral hepatitis. This study aimed to investigate the impact of the single nucleotide polymorphisms (SNP) G-201A (rs1439490) in IP-10 gene on disease progression of hepatitis B virus (HBV) infection. The -201 SNP in IP-10 promoter was genotyped from 577 patients with different illness categories and 275 health controls; In vitro IP-10 promoter activity was compared between haplotype GG and AA homozygotes using luciferase reporter system in HepG2 cells. In vivo expression of IP-10 was compared between patients with -201 AA genotype and GG genotype. The detected frequency of G-201A SNP was 17.8%, 25.3%, 26.6%, and 13.8% for patients with acute hepatitis B (AHB), patients with mild chronic hepatitis B (CHB-M), patients with severe chronic hepatitis B (CHB-S), and health controls, respectively. In vitro IP-10 promoter-driven luciferase activity in pGL3-Enhancer-201A transfected HepG2 cells was 1.43-fold higher than that in pGL3-Enhancer-201G transfected HepG2 cells (P<0.01). In vivo IP-10 transcriptional expression of peripheral blood mononuclear cells was 1.38-fold higher in patients with -201 AA genotype than in patients with -201 GG genotype (P<0.01). G-201A in promoter region of IP-10 gene was associated with liver disease progression in patients with HBV infection through up-regulating IP-10 expression.
    PLoS ONE 01/2013; 8(9):e72799. · 3.73 Impact Factor
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    ABSTRACT: It remains unclear whether hepatitis B virus (HBV) reverse-transcriptase (RT) rtL229 substitutions influence HBV drug resistance. The study was to investigate the association of HBV rtL229 substitutions with viral resistance to lamivudine (LAM). Entire HBV RT genes were amplified by nested PCR and sequenced from sera of 6000 nucleos(t)ide analog-experienced patients with chronic HBV infection. The incidence and clinic relevance of rtL229 substitutions were analyzed. Replication-competent viral amplicons which harbored HBV genomes of wild-type, rtM204I, or rtM204I in conjunction with various rtL229 substitutions (rtL229F/W/M/V) were constructed. The amplicons were transfected into HepG2 cells for phenotyping of replication capacity and susceptibility to nucleos(t)ide analogs. The rtL229 substitutions were detected in 6.57% (394/6000) of patients. Individual substitution incidences were 2.77%, 0.97%, 0.83% and 0.55% for rtL229V, rtL229F, rtL229M and rtL229W, respectively. The incidence of rtL229 substitutions was significantly higher in LAM-experienced patients (341/4220, 8.1%) than in LAM-naïve patients (53/1780, 3.0%), and were independently associated with genotypic LAM resistance (77.9% vs. 21.2%, OR 8.806, 95%CI 6.345-12.223) and low viral replication (HBV DNA <1000IU/mL) (4.60% vs. 24.2%, OR 0.478, 95%CI 0.254-0.898). Representative cases follow-up showed that rtL229F developed subsequent to rtM204I emergence during LAM treatment and regressed with rtM204I after LAM withdrawal. Functionally, rtL229F did not confer reduced susceptibility to LAM, but could restore replication capacity of rtM204I strain. The rtL229 substitutions were potentially associated with LAM resistance in Chinese patients and rtL229F had characteristics of a compensatory mutation of rtM204I mutant.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 03/2012; 54(1):66-72. · 3.12 Impact Factor
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    ABSTRACT: The mimotopes of viruses are considered as the good targets for vaccine design. We prepared mimotopes against multiple subtypes of influenza A and evaluate their immune responses in flu virus challenged Balb/c mice. The mimotopes of influenza A including pandemic H1N1, H3N2, H2N2 and H1N1 swine-origin influenza virus were screened by peptide phage display libraries, respectively. These mimotopes were engineered in one protein as multi- epitopes in Escherichia coli (E. coli) and purified. Balb/c mice were immunized using the multi-mimotopes protein and specific antibody responses were analyzed using hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA). The lung inflammation level was evaluated by hematoxylin and eosin (HE). Linear heptopeptide and dodecapeptide mimotopes were obtained for these influenza virus. The recombinant multi-mimotopes protein was a 73 kDa fusion protein. Comparing immunized infected groups with unimmunized infected subsets, significant differences were observed in the body weight loss and survival rate. The antiserum contained higher HI Ab titer against H1N1 virus and the lung inflammation level were significantly decreased in immunized infected groups. Phage-displayed mimotopes against multiple subtypes of influenza A were accessible to the mouse immune system and triggered a humoral response to above virus.
    Virology Journal 12/2011; 8:542. · 2.09 Impact Factor
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    ABSTRACT: The study aimed to develop an effective method to quantitate HBV covalently closed circular DNA (cccDNA) using small section of formalin fixed paraffin-embedded (FFPE) liver biopsy. Plasmid-safe ATP-dependent DNase (PSAD)-treated samples were subjected to rolling circle amplification (RCA) prior to real-time PCR mediated by cccDNA-selective primers. Human beta-actin gene was used as a reference control. Compared to the classical method, i.e., PSAD digestion+real-time PCR, introduction of RCA increased the lower limit of detection for about 2 logs with good inter- and intra-assay reproducibility. HBV cccDNA was detected in 91.5% (119/130) of the FFPE samples. The cccDNA levels (copy/cell) between FFPE liver tissues and fresh frozen counterpart tissues were comparable. The median of cccDNA level in HBeAg-positive patients was higher than that in HBeAg-negative ones (52.60 vs. 31.25copies/cell, P<0.01). Intrahepatic cccDNA level was positively correlated with intrahepatic HBV total DNA level, but not obviously correlated with serum HBV DNA or alanine aminotransferase levels. The method could sensitively and specifically quantitate intrahepatic HBV cccDNA in micro FFPE liver biopsy tissue for evaluation of HBV replication status in the liver.
    Clinica chimica acta; international journal of clinical chemistry 10/2011; 412(21-22):1905-11. · 2.54 Impact Factor
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    ABSTRACT: To investigate the features of hepatitis B virus (HBV) basal core promoter/precore (BCP/PC) mutations and genotypes in a large number of mild/severe chronic hepatitis B (CHB-M/CHB-S), and acute-on-chronic liver failure (ACLF) patients and analyze the clinical implications of the virologic features. Sera of 793 (325 CHB-M, 170 CHB-S, and 298 ACLF) patients admitted to or who had visited Beijing 302 Hospital from January 2005 to December 2008 were collected and successfully amplified for the HBV BCP/PC and a 1225-bp-long S/Pol (nt 54-1278) gene regions. Biochemical and serological parameters and HBV DNA level were routinely performed. Viral DNA was extracted and subjected to a nested PCR. Genotypes/subgenotypes were determined based on complete genomic sequence or on analysis of the 1225-bp-long S/Pol-gene sequence. HBV genotyping was performed by direct PCR sequencing followed by molecular evolutionary analysis of the viral sequences. A P value of <0.05 (two-sided) was considered to be statistically significant. Our findings suggest that CHB patients infected with BCP/PC mutant viruses are more susceptible to severe hepatitis and ACLF than those with the BCP/PC wild-type virus and that ACLF patients with PC mutant viruses have an increased risk of death. As such, the HBV PC mutation is a potential predictive indicator of ACLF outcome.
    Journal of Gastroenterology 03/2011; 46(3):391-400. · 3.79 Impact Factor
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    ABSTRACT: The hepatitis B virus (HBV) is a major etiological factor of inflammation and damage to the liver resulting in hepatocellular carcinoma. Transcription factors play important roles in the disordered gene expression and liver injury caused by HBV. However, the molecular mechanisms behind this observation have not been defined. In this study, we observed that circulating prostaglandin (PGE) 2 synthesis was increased in patients with chronic hepatitis B infection, and detected elevated cyclooxygenase (COX)-2 expression in HBV- and HBx-expressing liver cells. Likewise, the association of HBx with C/EBPβ contributed to the induction of COX-2. The COX-2 promoter was hypomethylated in HBV-positive cells, and specific demethylation of CpG dinucleotides within each of the two NF-AT sites in the COX-2 promoter resulted in the increased binding affinity of NF-AT to the cognate sites in the promoter, followed by increased COX-2 expression and PGE2 accumulation. The DNA methylatransferase DNMT3B played a key role in the methylation of the COX-2 promoter, and its decreased binding to the promoter was responsible for the regional demethylation of CpG sites, and for the increased binding of transcription factors in HBV-positive cells. Our results indicate that upregulation of COX-2 by HBV and HBx is mediated by both demethylation events and recruitment of multiple transcription factors binding to the promoter.
    Virology Journal 03/2011; 8:118. · 2.09 Impact Factor
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    ABSTRACT: Lipopolysaccharide (LPS) is suspected to trigger primary biliary cirrhosis (PBC) in susceptible individuals, yet the precise mechanism of its effect in PBC remains largely unknown. The aim of this study was to investigate altered responses to LPS ligand for Toll-like receptors (TLRs) in pathogenesis of PBC in vivo and in vitro. In vivo, we investigated levels of LPS and pro-inflammatory cytokines in sera and expression of LPS receptors in liver tissues from 162 patients with PBC, 325 patients with other liver diseases and 80 healthy controls. In vitro, altered responses to LPS on monocytes and cultured human biliary epithelial cells (BECs) from patients with PBC were determined. Significantly higher levels of LPS in patients with PBC were detected, compared with patients with other liver diseases and healthy controls. Immunohistochemically, expression of TLR4, CD14, CD68 and NF-κB was significantly enhanced in liver tissues from patients with PBC. Before LPS stimulation, we found significantly higher serum levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-8 in patients with PBC than those in healthy controls. After LPS stimulation, TLR4 expression and pro-inflammatory cytokine production in CD14-positive monocytes and cultured BEC from patients with PBC increased significantly. These results indicated that patients with PBC were prone to exhibit higher serum LPS level, hypersensitivity of monocytes and BEC to LPS, and enhanced production of pro-inflammatory cytokines. LPS altered expression of TLR4, CD14 and NF-κB on monocytes and BEC, which may be implicated in the pathogenesis and progression of PBC.
    Scandinavian journal of gastroenterology 01/2011; 46(4):485-94. · 2.08 Impact Factor
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    ABSTRACT: Different HBV genotypes have effect on the progression and outcome of chronic hepatitis B (CHB) and on the response to antiviral therapy. Accurate and sensitive genotyping methods are needed in clinical practice. In this multicenter retrospective study, 504 HBV DNA positive serum or plasma samples of CHB patients or asymptomatic carriers were genotyped by INNO-LiPA HBV genotyping and direct sequencing. A part of the consistent and discrepant results were confirmed by clonal sequencing. Except two samples with indeterminate results by INNO-LiPA, 463 had the same genotype results by INNO-LiPA and direct sequencing with a concordance of 92.23% (463/502). However 24 had completely inconsistent results by the two methods, seven of which were confirmed by clonal sequencing as the same genotype as by direct sequencing. Fifteen samples were determined as B/C mixed genotypes by INNO-LiPA but singe B or C genotype by direct sequencing, five of which were confirmed by clonal sequencing as B/C mixed infection. Further studies showed INNO-LiPA could detect 6% of genotype B and genotype C among mixed genotype samples at HBV DNA ≥3×10(3) IU/ml. INNO-LiPA is accurate and sensitive in detecting B, C, D and B/C mixed genotype infection in Chinese CHB patients and asymptomatic carriers.
    Clinica chimica acta; international journal of clinical chemistry 12/2010; 411(23-24):1951-6. · 2.54 Impact Factor
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    ABSTRACT: There is no animal model that displays the features of non-alcoholic steatohepatitis (NASH) characterized by insulin resistance (IR) and fibrosing steatohepatitis. This study aimed to develop a novel IR-associated rat model of NASH. Male Sprague-Dawley rats were fed with the high-fat diet (HFD) supplemented with 0.25% propylthiouracil for 2, 4, 6, 8 and 12 weeks. The IR-associated metabolic parameters, histological assessment and the expression of key insulin signaling molecules were determined. The circulating and tissue pro-inflammatory factors and adipocytokines were examined. In the HFD-fed rats, the systemic and multiple-organ IR was developed after 4 weeks, whereas the histological changes characterized by steatohepatitis, inflammatory response in the visceral adipose tissue and proliferative pancreatic islet β-cells appeared after 6 weeks, concomitant with altered expression of key insulin signaling molecules. In addition, the elevated levels of serum tumor necrosis factor α (TNF-α), soluble TNF receptor2, interleukin (IL)-6, CC-chemokine ligand (CCL)2 and resistin were parallel with the severity of hepatic inflammation, while the levels of serum adiponectin, leptin and TNF-α, but not resistin, were correlated with IR. We have developed a systemic IR-associated NASH model of rats, with impaired insulin signaling, systemic inflammation and appropriate pathology characterized by human NASH, and provided a realistic experimental model for elucidating the association between IR and the pathogenesis of NASH.
    Scandinavian journal of gastroenterology 11/2010; 45(11):1360-71. · 2.08 Impact Factor
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    ABSTRACT: Various mutations in reverse-transcriptase domain (RT) of hepatitis B virus (HBV) polymerase may develop during antiviral therapy. The influence of these mutational patterns on HBV replication capacity remains to be fully clarified. Nine clones containing complete HBV genomes were isolated from 5 patients with chronic hepatitis B who had received antiviral treatment. Viral replication capacity was measured by quantitation of HBV replicative intermediates using vector-free transfer of paired mutant and wild-type HBV genomes into human hepatoma cell lines HepG2 and Huh7. HBV pgRNA was quantitated by real-time PCR and Southern blot analysis. A real-time PCR assay with high sensitivity and small variation was developed for quantitation of HBV replicative intermediates. Compared to wild-type counterpart, mutant rtL217P produced 1.98-fold higher replicative intermediate level, and mutant rtM204I+rtL217P increased the replicative intermediate level to 1.20 fold. Other mutational patterns (rtV173M, rtA181S/V, rtM204I, rtQ215H, rtL229M, rtN238H, rtV84M+rtA181S+rtM204I, rtV84M+rtM204I, rtA181S+rtM204I, rtA181V+rtL229M, rtQ215H+rtN238H) reduced viral replication capacity to different extents. The study offers a practical measurement assay and novel information for replication features of mutant strains; especially, rtL217P substitution likely represents an energetic replication-compensatory mutation.
    Clinica chimica acta; international journal of clinical chemistry 11/2010; 412(3-4):305-13. · 2.54 Impact Factor
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    ABSTRACT: We aimed to study the prevalence and clinical implications of hepatitis B virus (HBV) subgenotypes in Chinese patients. A total of 4,300 patients, mainly from northern China, were enrolled, including 182 patients with acute hepatitis B and 4,118 patients with chronic HBV infection who had been exposed to nucleoside or nucleotide analogs. HBV genotypes/subgenotypes were determined by direct sequencing of the HBV S/Pol region. The prevalence rates were 0.40% for HBV/B1, 14.30% for HBV/B2, 0.25% for HBV/B3, 0.35% for HBV/B4, 1.05% for HBV/C1, 81.72% for HBV/C2, 0.93% for HBV/C3, 0.16% for HBV/C4, and 0.84% for HBV/D. In chronic HBV infection, patients with HBV/B2 were younger and had lower ΗBeAg positive rates than patients with HBV/C2. The incidence of lamivudine-resistant mutations was significantly higher in HBV/C2 compared to HBV/B2 (27.9% versus 19.8%; P<0.01), and the significant difference was observed only for rtM204I and not rtM204V. In addition, compensatory mutations were more frequently detected in HBV/C2. The incidence of adefovir-resistant mutations was similar between the two subsets, but HBV/C2 inclined to show rtA181V (3.6% for C2 versus 0.9% for B2; P<0.01), while HBV/B2 inclined to show rtN236T (4.5% for versus 2.5% for C2; P<0.01). The ratios of HBV/B2 to HBV/C2 infection were 1.7 (110/65), 5.7 (2,653/463), 7.5 (520/69), 8.0 (48/6), and 15.3 (183/12) for acute hepatitis B, chronic hepatitis B, liver cirrhosis, acute-on-chronic liver failure, and hepatocellular carcinoma, respectively. In conclusion, HBV/C2 and HBV/B2, two prevalent subgenotypes, differ in lamivudine- and adefovir-resistance-associated mutational patterns. HBV/C2-infected patients are more likely to have disease progression than HBV/B2-infected ones.
    Journal of clinical microbiology 09/2010; 48(12):4363-9. · 4.16 Impact Factor
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    ABSTRACT: Pre-existing antiviral-resistant hepatitis B virus (HBV) has been associated with primary non-response to lamivudine treatment in patients with chronic hepatitis B, but little is known of the capacity for resistant HBV to cause primary infection. The study was to investigate if Beijing patients with acute hepatitis B (AHB) are infected with drug-resistant HBV. Sera were collected from 201 NA-untreated patients with AHB. Direct polymerase chain reaction (PCR) sequencing was used to screen HBV reverse-transcriptase (RT) domain and clonal sequencing were performed for all resistance-positive samples. Direct PCR sequencing showed that 14 samples (7.0%) were positive for drug-resistant HBV variants, comprised of 11 with the lamivudine-resistant pattern rtM204I and/or rtM204V in the presence and absence of compensatory mutations rtL80I, rtV173L, and rtL180M; two with the adefovir-resistant pattern rtA181V; and one with the entecavir-resistant pattern rtL180M+rtS202G+rtM204V. Concomitance of resistance variants with wild-type HBV was observed in samples from 13 patients. Clonal sequencing verified direct sequencing results. Furthermore, variants associated with resistance to adefovir or entecavir were found in 3 samples. Drug-resistant HBV strains, including those not resistant to lamivudine, are transmissible and can cause acute hepatitis B in China.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 08/2010; 48(4):270-4. · 3.12 Impact Factor
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    ABSTRACT: The association of hepatitis B virus (HBV) genotypes and basal core promoter (BCP) and precore (PC) mutations with the clinical characteristics is increasingly recognized. To investigate virologic features and clinical implications of HBV genotypes, BCP and PC mutations between large-size patients with acute hepatitis B (AHB) and chronic hepatitis B (CHB). One hundred and eighty-two AHB patients and 325 CHB patients were investigated. HBV genotypes and BCP/PC mutations were determined by direct sequencing. Mutations at 10 interested sites of the BCP/PC region were compared between the two groups of patients. AHB patients had a significantly higher ratio of genotype B to C than CHB patients (37.4-62.6% vs. 16.6-83.4%, P<0.001). The prevalence of BCP/PC wild-type virus was 60.4% in AHB patients in contrast to 28.9% in CHB patients. Significantly lower prevalence of A1762T, G1764A, G1896A, and G1899A but higher prevalence of T1758C was found in AHB patients. Interestingly, T1758C and A1762T/G1764A appeared mutual restraint. Genotype B virus had lower BCP mutation frequency and similar PC mutation frequency compared to genotype C virus. AHB patients with BCP/PC mutant virus had higher viral load, whereas CHB patients with BCP/PC mutant virus had lower viral load and elevated alanine aminotransferase, in comparison with those with the wild-type virus. Patients with genotype B virus, BCP/PC wild-type virus or T1758C mutant virus were more susceptible to develop AHB, whereas high prevalence of the BCP/PC mutations was associated with CHB development.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 03/2010; 47(3):243-7. · 3.12 Impact Factor
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    ABSTRACT: Here, we report a case of multidrug resistance in a patient with chronic hepatitis B. The patient sequentially received lamivudine, adefovir dipivoxil and entecavir, and subsequently developed single-, double- and triple-drug-resistant HBV strains. We consider this case report important because it documents, for the first time, that triple-drug-resistant HBV strains identified in a clinical setting were suppressible by lamivudine add-on adefovir dipivoxil when tenofovir disoproxil fumarate was not available.
    Antiviral therapy 01/2010; 15(8):1185-90. · 3.07 Impact Factor

Publication Stats

511 Citations
14 Downloads
1k Views
149.66 Total Impact Points

Institutions

  • 2013
    • Guilin Medical University
      Ling-ch’uan, Guangxi Zhuangzu Zizhiqu, China
  • 2004–2013
    • 302 Military Hospital of China
      Peping, Beijing, China
  • 2010
    • The Chinese University of Hong Kong
      • Department of Medicine and Therapeutics
      Hong Kong, Hong Kong