Guang-Wen Zhang

Nanfang Hospital, Guangzhou, Guangdong Sheng, China

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Publications (10)22.44 Total impact

  • Article: Complementarity-determining region 3 size spectratypes of T cell receptor beta chains in CD8+ T cells following antiviral treatment of chronic hepatitis B.
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    ABSTRACT: An increased CD8(+) T cell response to hepatitis B virus (HBV) peptides occurs between 12 and 24 weeks after starting antiviral therapy for chronic hepatitis B. It is not known whether these cells have antiviral function. The aim of this study was to determine whether clonal expansions of CD8(+) T cells at these time points predict the virological response to therapy. Peripheral blood CD8(+) T cells were obtained from 20 patients treated with lamivudine or telbivudine for chronic hepatitis B at baseline, 12 weeks, and 24 weeks. The CDR3 spectratype of each T cell receptor (TCR) β chain variable region (Vβ) gene family was analyzed, and the changes in the numbers of Vβ families with clonal expansions were compared in subjects with (n = 12) and without (n = 8) a virological response (52 week HBV DNA < 300 copies/ml). The number of CD8(+) TCR Vβ families with clonal expansions at 12 weeks relative to baseline (median [10th to 90th percentile], +2.5 [0 to +7] versus +1 [0 to +2], P = 0.03) and at 24 weeks relative to 12 weeks (+1 [0 to +2] versus -1 [-3 to +4], P = 0.006) was higher in subjects with a virological response versus subjects without a virological response, as were interleukin-2 (IL-2) but not IL-21 mRNA levels in peripheral blood mononuclear cells. The duration of new expansions at 12 weeks was higher (P < 0.0001) in responders. Increased numbers of CD8(+) T cell expansions after antiviral therapy are associated with a virological response to treatment. These CD8(+) T cells are a potential target for a therapeutic vaccine for chronic hepatitis B.
    Antimicrobial Agents and Chemotherapy 02/2011; 55(2):888-94. · 4.84 Impact Factor
  • Article: [Characteristics of CDR3 of TCR beta on CD8+ T cells in chronic hepatitis B patients].
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    ABSTRACT: To analyze the characteristics of CDR3 of TCRbeta on CD8+ T cells in chronic hepatitis B patients. Eight patients with chronic hepatitis B (ALT more than 2 ULN) were enrolled in this study. CD8+ T cells were isolated from peripheral blood. RT-PCR was proformed to amplify the CDR3 of TCRbeta, and the PCR products were sequenced and analyzed. The chronic hepatitis B patients showed obvious clonal expansion of T cell, and three perturbation patterns of T cell expansion were showed in the CDR3 of TCRbeta, including monoclonicity, oligoclonicity and skewed peak patterns. The number of perturbation families of CD8+ subpopulation was significantly higher than that of CD8- subpopulation (10.6+/-4.7 vs. 4.1+/-3.1, t = 6.619, P less than 0.01). In 3 out of 8 patients, the number of perturbation families of CD8+ subpopulation was also higher than that of PBMCs without depleting CD8+ subpopulation. The characteristics of CDR3 of TCRbeta may help to understand the inflammatory response in CHB patients.
    Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology 03/2010; 18(3):184-8.
  • Article: Imperatorin is responsible for the vasodilatation activity of Angelica Dahurica var. Formosana regulated by nitric oxide in an endothelium-dependent manner.
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    ABSTRACT: To demonstrate the vasodilatation activity of the coumarin-containing Angelica dahurica var. formosana and to further analyze active components in the herb extracts. (1) The vasodilatation effects induced by different extracts (cyclohexane, ethyl acetate, acetone, methanol, 95 % ethanol and water) of Angelica dahurica var. formosana on mouse thoracic aorta pre-contracted with phenylephrine were investigated. (2) The amount of imperatorin and isoimperatorin in each extract was measured by high-performance liquid chromatography. (3) The vasodilatation effects of imperatorin and isoimperatorin on mouse thoracic aorta were compared using the same in vitro method. (4) The vasodilatation mechanism of imperatorin in the mouse thoracic aorta pre-contracted with phenylephrine was studied using the methods of denuded endothelium, NG-nitro-L-arginine methylester (L-NAME, a nitric oxide synthase inhibitor), and propranolol. (1) The cyclohexane and ethyl acetate extracts of Angelica dahurica var. formosana decreased the maximal response of phenylephrine-induced mouse thoracic aorta contraction dose-dependently, with 50% inhibiting concentration (IC(50)) values of 35.3+/-12.4 mg/L and 40.5+/-12.0 mg/L, respectively. The vasodilatation effect of imperatorin and isoimperatorin was dose-dependent. (2) The cyclohexane extract, showing the strongest vasodilatation effect, possessed the highest contents of imperatorin (4.09%) and isoimperatorin (0.27%, w/w). There was a correlation between the vasodilatation activity and the contents of imperatorin and isoimperatorin in the extracts. (3) The vasodilatation effect of imperatorin was about 4-fold stronger than that of isoimperatorin. (4) The vasodilatation effect of imperatorin was signifificantly attenuated to 24.88%+/-4.06% in the denuded endothelium group compared with the intact endothelium group. And 1 mmol/L L-NAME reduced the imperatorin-induced vasorelaxation by 32.18 %+/-11.29 %. The principal effective component of Angelica dahurica var. Formosana was found to be imperatorin. Imperatorin-induced vasodilatation is at least partially regulated by nitric oxide, and has no correlation to beta-receptor.
    Chinese Journal of Integrative Medicine 12/2009; 15(6):442-7. · 0.80 Impact Factor
  • Article: Two new bioactive sesquiterpenes from the soft coral Sinularia sp.
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    ABSTRACT: Two new sesquiterpenes, 1S*, 4R*, 5S*, 6R*, 7S*, 10S*-1(5), 6(7)-diepoxy-4-guaiol (1) and 1S*, 4S*, 5S*, 10R*-4,10-guaianediol (2) have been isolated from the ethyl acetate soluble portion of the soft coral Sinularia sp., and their stereostructure were determined by spectroscopic methods and by X-ray single crystal analysis. Both compounds showed antioxidant and cytotoxic activities.
    Natural Product Research 07/2006; 20(7):659-64. · 1.01 Impact Factor
  • Article: Analysis of the CDR3 length of TCR alphabeta T cells in the peripheral blood of patients with chronic hepatitis B.
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    ABSTRACT: To clarify the characteristics of TCR alphabeta T cells in the peripheral blood of patients with chronic hepatitis B (CHB), we investigated the patterns of Complementarity Determining Region3 (CDR3) length distribution for all 24 TCR BV gene families and 32 TCR AV gene family in the peripheral blood lymphocytes of two patients with CHB and two healthy controls by immunoscope spectratyping technique. We found that the profiles of CDR3 length distribution for all TCR AV and TCR BV family showed Gaussian distribution (the polyclonal TCR alphabeta T cells) in healthy controls, however, the restricted usage of TCR BV and TCR AV family (the oligoclonal TCR alphabeta T cells) has been monitored in two CHB patients, furthermore, the oligoclonal TCR alphabeta T cells showed the different CDR3 sequences and length, it might be correlated to the different epitope of hepatitis B virus (HBV) or the different HLA type of the patients. Detailed analysis of the CDR3 length of TCR alphabeta T cells might be interesting to light on the further study of the individualized immunotherapy of CHB and the further research of the new T lymphocyte epitope vaccine of HBV.
    Hepatology Research 06/2006; 35(1):10-8. · 2.20 Impact Factor
  • Article: [Analysis of T cell receptor BV dominant usage and CDR3 sequences during acute exacerbation in patients with chronic hepatitis B].
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    ABSTRACT: To understand the role cellular immunology plays in the pathogenesis of chronic hepatitis B (CHB) through analysis of T cell receptor (TCR) beta chain variable region gene (BV) family dominant usage and beta chain complementarity determining region3 (CDR3) sequences of peripheral blood mononuclear cells of the patients. TCR BV families were amplified by inverse polymerase chain reaction (RT-PCR), and the dominant usage of BV families and CDR3 repertoire were analyzed by immunoscope technology for 8 CHB patients during their acute exacerbations and for 4 healthy blood donors who served as controls. The clonality of the T cells suspected by immunoscope was further confirmed by CDR3 sequencing. The TCR BV CDR3 repertoire of the 4 healthy blood donors showed a Gaussian distribution. In the 8 CHB patients, however, the clonal expansion of T cells showed different TCR BV families with each patient. The T cells of the clonal expansion shared different CDR3 sequences. The peripheral blood T cells of CHB patients during their acute exacerbation showed significantly a clonal expansion and their T cell clonal expansion may be stimulated by several HBV epitopes. These results indicate that cellular immunology is involved in the pathogenesis of the liver inflammation process of CHB.
    Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology 02/2006; 14(1):23-8.
  • Article: Cytotoxic diterpenoids from the soft coral Sinularia microclavata.
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    ABSTRACT: The soft coral Sinularia microclavata collected from the bay of Sanya, Hainan Island, China, yielded a new diterpenoid, microclavatin (1), and a known cembranolide, capillolide (2). The structure of compound 1 was determined on the basis of spectroscopic methods and X-ray single-crystal diffraction analysis. Microclavatin (1) showed cytotoxic activities against tumor cell lines KB and MCF with IC50 values of 5.0 and 20.0 microg/mL, respectively, and capillolide (2) showed potent cytotoxic activity against tumor cell lines (A-549) with an IC50 value of 0.5 microg/mL.
    Journal of Natural Products 08/2005; 68(7):1087-9. · 3.13 Impact Factor
  • Article: Two New Ceramides from the Marine Sponge Ircinia fasciculata
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    ABSTRACT: A new 4-sulfated ceramide, ircisulfamide (=N-[(1S*,2S*,3R*)-2-hydroxy-1-(hydroxymethyl)-3-(sulfooxy)heptadecyl]hexadecanamide; 1), and a new glycosphingolipid, ircicerebroside (=(2R*)-N-{(1S*,2R*,3E,7E)-1-[(β-D-glucopyranosyloxy)methyl]-2-hydroxy-8-methylheptadeca-3,7-dienyl}-2-hydroxyeicosanamide; 2), were isolated from the aqueous EtOH extract of the marine sponge Ircinia fasciculata (Pallas). The structures of the new compounds were elucidated on the basis of spectroscopic analysis and by means of chemical methods.
    Helvetica Chimica Acta 04/2005; 88(4):885 - 890. · 1.48 Impact Factor
  • Article: New hemiketal steroid from the soft coral Cladiella sp.
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    ABSTRACT: [structure: see text] A new hemiketal steroid, named cladiellin A (1), was first isolated from the soft coral Cladiella sp. Its structure was determined by spectroscopic methods and X-ray analysis. Compound 1 easily converted to 1a when NMR spectra were measured in CDCl(3) solution and quickly changed to 1b when pyridine was used. The structures of dehydrated products 1a and 1b were determined by spectroscopic analysis. Bioassay showed that all these three compounds showed antioxidant activity.
    Organic Letters 04/2005; 7(6):991-4. · 5.86 Impact Factor
  • Article: Two new cytotoxic tetracyclic tetraterpenoids from the soft coral Sarcophyton tortuosum.
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    ABSTRACT: Two new cytotoxic tetracyclic tetraterpenoids, methyl tortuoate A (1) and methyl tortuoate B (2), along with the known methyl sartortuoate (3) were isolated from the soft coral Sarcophyton tortuosum. The structures of 1 and 2 were established by spectroscopic methods, mainly on the basis of 2D NMR techniques, and were confirmed by single-crystal X-ray diffraction analysis. The cytotoxic activities of these compounds were carried out in vitro on human nasophyringeal carcinoma (CNE-2) and murine lymphocytic leukemia (P-388) tumor cell lines.
    Journal of Natural Products 12/2004; 67(11):1915-8. · 3.13 Impact Factor