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Publications (6)33.4 Total impact

  • Article: Effects of bezafibrate in patients with chronic hepatitis C virus infection: combination with interferon and ribavirin.
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    ABSTRACT: An association of hepatitis C virus (HCV) with low-density lipoproteins (LDL) in serum of patients with chronic hepatitis C (CHC) has been suggested. We conducted a prospective study in CHC patients complicated with hyperlipidaemia, to examine whether bezafibrate, which is commonly used for treatment of hyperlipidaemia, reduces serum HCV-RNA titre and improves liver dysfunction. Fifteen patients received daily oral bezafibrate treatment (400 mg/day) for 8 weeks, and its effects on serum lipids, transaminases, HCV-RNA titres, and HCV-RNA titres bound to LDL were evaluated. Fifteen untreated patients with CHC and hyperlipidaemia were used as controls. The mean serum alanine aminotransferase levels and HCV-RNA titres significantly decreased at the end of bezafibrate therapy in the treated group (105 +/- 34 to 80 +/- 32 IU/L, P = 0.02 and 2.23 +/- 2.71 to 1.78 +/- 2.38 x 10(7) copies/mL, P < 0.01 respectively), but no changes were observed in the control group. Serum HCV-RNA titres bound to LDL, as quantified by immunoprecipitation using anti-LDL antibody, also decreased in all 15 treated patients [5.55 +/- 6.59 to 1.07 +/- 1.58 x 10(6) copies/ml, P < 0.01 (mean reduction rate was -78.5 +/- 17.0%)]. Sucrose density-gradient ultracentrifugation study revealed that HCV-RNA-decreased density fractions after the bezafibrate were identical to LDL-density fractions (1.015-1.062 g/mL). Eight CHC patients were treated with bezafibrate, interferon, and ribavirin triple therapy for 32 weeks, and four patients achieved sustained virological response to therapy. This pilot study provides further evidence of an association between HCV and LDL in serum and suggests the potential usefulness of bezafibrate as an anti-HCV reagent for the treatment of CHC patients.
    Journal of Viral Hepatitis 08/2006; 13(7):441-8. · 4.09 Impact Factor
  • Article: Hepatitis C virus free-virion and immune-complex dynamics during interferon therapy with and without ribavirin in genotype-1b chronic hepatitis C patients.
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    ABSTRACT: The Synergistic effect of interferon (IFN) and ribavirin for patients with chronic hepatitis C has been demonstrated, but ribavirin has no apparent direct antiviral effect against hepatitis C virus (HCV) when used as monotherapy. To elucidate the mechanism of ribavirin on enhanced HCV eradication when used in combination therapy, we investigated the serum HCV dynamics of free-virions (FV) and immune-complexes (IC) in genotype-1b infected patients treated with IFN-alpha2b alone (n = 11) or in combination with ribavirin (n = 15). Serum FV- and IC-HCV RNA were separated by immunoprecipitation using anti-human immunoglobulin and quantified serially using real-time detection polymerase chain reaction. At the first phase (day 0-2), the decline of FV- and IC-HCV RNA was similar between the two treatment groups. At the second phase (day 2-28), the decline of IC was significantly faster in patients treated with IFN plus ribavirin compared with IFN alone [exponential decay slope = 0.079 +/- 0.036 vs 0.048 +/- 0.027 log10/day, P = 0.0248; half-life = 81.1 +/- 21.4 vs 135.1 +/- 61.4 h, P = 0.0053], although the second phase FV-decline was not significantly different between the two treatment groups. The fast second phase decline of IC was associated with sustained virological response to therapy. These results suggest that ribavirin may modulate the humoral immune response against HCV and trigger a favourable response to IFN. In conclusion, analysis of early IC-HCV dynamics is useful for predicting the response to therapy and for understanding the mechanism of action of antiviral drugs in chronic hepatitis C patients.
    Journal of Viral Hepatitis 04/2006; 13(3):190-8. · 4.09 Impact Factor
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    Article: Hepatitis C virus particle detected by immunoelectron microscopic study.
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    ABSTRACT: To clarify the morphology of hepatitis C virus (HCV), an indirect immunogold electron microscopic study was carried out on two plasma samples with high HCV RNA titres using polyclonal and monoclonal antibodies specific to the putative HCV envelope protein. Spherical virus-like particles, 55 to 65 nm in diameter with spike-like projections, were found in 1.14 to 1.16 g/ml fractions after sucrose density gradient centrifugation. These particles were found only in HCV-infected blood donors and had morphological features similar to those of flaviviruses. Moreover, these particles specifically reacted with the polyclonal and monoclonal antibodies to the putative HCV envelope protein. This is the first known report in which the morphology of the HCV particle is clearly shown.
    Journal of General Virology 08/1994; 75 ( Pt 7):1755-60. · 3.36 Impact Factor
  • Article: Quantitation and typing of serum hepatitis C virus RNA in patients with chronic hepatitis C treated with interferon-beta.
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    ABSTRACT: We quantified serum hepatitis C virus RNA titers and determined hepatitis C virus subtypes in chronic hepatitis C patients treated with interferon-beta to investigate relationships among serum ALT response, serum hepatitis C virus titer and hepatitis C virus subtype. Of 146 chronic hepatitis C patients who received interferon-beta therapy, 24 patients with sustained serum ALT normalization (complete responders) and 26 patients without serum ALT normalization (nonresponders) were randomly selected. Detection, typing and quantitation of hepatitis C virus were performed by means of the "single-tube" polymerase chain reaction method. Of the 24 complete responders, 21 (87.5%) became negative for hepatitis C virus RNA, whereas 21 (80.8%) of the 26 nonresponders remained positive. Hepatitis C virus infections with types I, II, III, IV, II + III and III + IV occurred in 0 (0%), 22 (51.2%), 10 (23.3%), 1 (2.3%), 7 (16.5%) and 3 (7.9%) patients, respectively. The mean pretreatment hepatitis C virus RNA titer of complete responders (0.4 +/- 2.0 x 10(4) CID50/ml) was significantly lower than that of nonresponders (3.8 +/- 4.5 x 10(4) CID50/ml) (p < 0.01). Regardless of HCV subtype, patients with more than 10(4) CID50/ml of HCV did not show serum ALT normalization, whereas complete serum ALT response was seen in most cases with less than 10(2) CID50/ml HCV. These results show that mixed infections with different hepatitis C virus subtypes appear to be more common than previously reported and that the pretreatment serum level of hepatitis C virus RNA is a more important predictor of outcome of interferon therapy than is virus genotype.
    Hepatology 01/1994; 18(6):1319-25. · 11.66 Impact Factor
  • Article: Appropriate interferon-alpha therapy for chronic hepatitis C: an assessment by quantitative changes in serum hepatitis C virus-RNA.
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    ABSTRACT: The antiviral effect of natural interferon (IFN)-alpha on chronic hepatitis C virus (HCV) infection was estimated by determining quantitative changes in serum HCV-RNA compared with the serum alanine aminotransferase (sALT) improvement; the relationships of responses to IFN according to the dose and period of IFN therapy were defined to determine an appropriate IFN therapy protocol. Twenty-two patients with chronic hepatitis C were given natural IFN-alpha and in 16 (72.7%) patients the viraemia was suppressed during therapy. Five (27.7%) of them sustained the disappearance of HCV-RNA for more than 6 months after therapy accompanied with a prolonged sALT improvement. Pre-treatment viraemia levels in 5 complete responders with "complete suppression" of viraemia were significantly lower than in 11 patients with a transient loss or a decline of HCV-RNA. A favorable antiviral response was closely associated with a high total dose of IFN-alpha and a long duration of IFN therapy.
    Internal Medicine 08/1993; 32(7):523-9. · 0.94 Impact Factor
  • Article: Detection of hepatitis C virus RNA by nested polymerase chain reaction in sera of patients with chronic non-A, non-B hepatitis treated with interferon.
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    ABSTRACT: To evaluate the effect of interferon-alpha treatment on the levels of serum aminotransferase (sALT) and of hepatitis C virus (HCV)-RNA, we studied 19 patients with chronic non-A, non-B (NANB) hepatitis. Before therapy, 14 patients were positive by nested polymerase chain reaction (PCR) with primers deduced from the 5'-non-coding region of the HCV genome. Serum HCV-RNA had disappeared in 12 (85.7%) of them by the end of therapy, but then reappeared 6 months later in 4 of these 12 patients. A marked improvement in sALT was seen in 5 of the 8 patients with sustained HCV-RNA disappearance, but not in the 4 patients with only transient HCV-RNA negativity. Pre-treatment levels of hepatitis C viremia, analyzed by single PCR and dot blot hybridization, ranged from 2 x 10(3) to 2 x 10(8) copies/ml, and were below 2 x 10(5) copies/ml in patients with a complete response to interferon therapy. These results suggest that this HCV-RNA assay, combined with sALT testing, may be useful for estimation of the long-term efficacy of interferon therapy in hepatitis C.
    Journal of Hepatology 10/1992; 16(1-2):138-44. · 9.26 Impact Factor