Biomedical subjects

V Carreño

Publications and source records attributed to V Carreño.

At least 19 recordsLinked to original sources

PubMed2007

Comparative study between occult hepatitis C virus infection and chronic hepatitis C.

We have recently described the presence of occult hepatitis C virus (HCV) infection (HCV-RNA in liver in the absence of anti-HCV and serum HCV-RNA) in patients with persistently abnormal liver function tests of unknown aetiology. The aim of this study was to compare the characteristics of patients with occult HCV infection vs those of patients with chronic hepatitis C. We compared clinical features of 68 patients with occult HCV infection and 69 untreated chronic HCV patients (anti-HCV and serum HCV-RNA positive), matched for age, gender, duration of abnormal liver function tests and body mass index. Aspartate aminotransferase and alanine aminotransferase were higher (P < 0.001) in chronic HCV, but cholesterol and triglycerides were significantly higher in patients with occult HCV infection (P < 0.001 and P = 0.002). Chronic HCV patients had higher gamma-globulin (P = 0.005), alpha-foetoprotein (P < 0.001) and iron (P < 0.001) levels. Percentage of patients with necroinflammatory activity and fibrosis was higher (P < 0.001) in chronic HCV than in occult HCV infection. Mean percentage of infected hepatocytes was higher (P = 0.001) in chronic HCV (10.1%) than in occult HCV infection (5.3%). This occult HCV infection is a milder disease than chronic HCV, and this could be related to the significantly lower number of infected hepatocytes observed in occult HCV.

Adult↗

PubMed2006

Effect of anti-viral therapy for occult hepatitis C virus infection.

BACKGROUND: Occult hepatitis C virus infection is defined by the presence of hepatitis C virus-RNA in liver but with undetectable anti-hepatitis C virus and serum viral RNA. AIM: To study the response to anti-viral therapy in occult hepatitis C virus infection to assess the pathogenic effect of occult hepatitis C virus. METHODS: Ten patients with occult hepatitis C virus infection were treated with pegylated-interferon plus ribavirin for 24 weeks and were followed-up 24 weeks after therapy. All patients had abnormal alanine aminotransferase, hepatitis C virus-RNA positive in peripheral blood mononuclear cells and liver necroinflammation. RESULTS: At the end of treatment and follow-up, the percentage of patients with normal alanine aminotransferase was 80% (95% CI: 48-96%) and 60% (95% CI: 31-84%) respectively, and hepatitis C virus-RNA in peripheral blood mononuclear cells was negative in 80% (95% CI: 48-96%) and 70% (95% CI: 40-90%) cases. At the end of follow-up sustained response was observed in 30% (95% CI: 11-61%) of cases. Five patients underwent a second liver biopsy. In all cases, liver hepatitis C virus-RNA persisted, although hepatitis C virus-RNA load was significantly lower (3.2 x 10(4) +/- 5.1 x 10(4) copies/microg RNA) than in the basal biopsy (2.4 x 10(5) +/- 3.8 x 10(5) copies/microg RNA); (P = 0.043). Necroinflammation and fibrosis decreased in three cases. CONCLUSION: The biochemical, virological and histological response to therapy achieved in patients with occult hepatitis C virus infection demonstrates the pathologic effects of occult hepatitis C virus.

Adult↗

PubMed2005

Hepatitis C virus (HCV) and hepatitis B virus (HBV) can coinfect the same hepatocyte in the liver of patients with chronic HCV and occult HBV infection.

In this work, we have shown that hepatitis C virus (HCV) and hepatitis B virus (HBV) can coexist in the same hepatocyte using double fluorescent in situ hybridization in liver biopsy samples from patients with chronic HCV infection with occult HBV infection. Digital image analysis of hybridization signals showed that the HBV DNA levels in coinfected hepatocytes were lower than those in cells infected only with HBV. This finding supports the hypothesis of inhibition of HBV replication by HCV. Furthermore, HCV RNA levels were lower in coinfected cells than in cells infected only with HCV, suggesting that HBV may also inhibit HCV replication.

Biopsy↗

PubMed2005

Hepatitis C virus replicates in peripheral blood mononuclear cells of patients with occult hepatitis C virus infection.

BACKGROUND: Occult hepatitis C virus (HCV) infection is characterised by the presence of HCV-RNA in the liver in the absence of anti-HCV, and serum viral RNA. Up to 70% of these patients also have HCV-RNA in peripheral blood mononuclear cells (PBMC) but it is not known if HCV is replicating in these cells. AIM: We studied possible HCV replication in PBMC of 18 patients with an occult HCV infection who were selected on the basis of HCV-RNA positivity in PBMC. METHODS: Detection of HCV-RNA positive and negative strands in PBMC was done by strand specific reverse transcriptase-polymerase chain reaction (RT-PCR) and by in situ hybridisation. RESULTS: The presence of HCV-RNA positive strand in PBMC was confirmed in all patients by strand specific RT-PCR and by in situ hybridisation. Mean percentage of PBMC which had the HCV-RNA positive strand was 3.3% (95% confidence interval (CI) 2.1-4.4) The HCV-RNA negative strand was found in the PBMC of 11/18 (61%) patients by strand specific RT-PCR and confirmed by in situ hybridisation, and the percentage of PBMC harbouring the HCV-RNA negative strand was 3.1% (95% CI 0.8-5.5). There was a significant correlation (p = 0.001, r = 0.84) between the percentage of PBMC with the HCV-RNA positive strand and that of PBMC with the HCV-RNA negative strand. CONCLUSION: HCV replicates in the PBMC of patients with occult HCV infection and thus, although these patients do not have serum HCV-RNA, they could be potentially infectious.

Adult↗

PubMed2004

Pegylated interferon-alpha2a kinetics during experimental haemodialysis: impact of permeability and pore size of dialysers.

BACKGROUND: Therapeutics in end-stage renal disease (ESRD) patients undergoing haemodialysis (HD) has to consider potential drug clearance during the dialysis procedure. Pegylated interferon-alpha (PEG-IFN-alpha), a middle-size protein drug active against viral hepatitis, allows convenient once-weekly dosing due to prolonged plasma half-life. AIM: To investigate the impact of permeability and dialyser pore size on PEG-IFN-alpha blood levels during experimental HD. METHODS: Polymethylmetacrylate (PMMA) membrane 1.6 m2 dialysers with three different permeabilities/pore sizes were selected. RESULTS: A 40 kDa PEG-IFN-alpha2a (PEGASYS) was not cleared (< 5%) through low-flux/small pore size (25 A;B3A) and high-flux/middle-large pore size (60 A;BKP) dialysers, and was partially (approximately 15%) through intermediate permeability/large pore size (100 A;BKF) dialysers. In contrast, unmodified 17 kDa IFN-alpha2a(Roferon-A) was removed (65%-95%) through BKP or BKF, but not B3A, PMMA dialysers. Moreover, 12 kDa PEG-IFN-alpha2b(PegIntron) was cleared (40%-80%) through PMMA dialysers with pore sizes > or = 60 angstroms. When B3A or BKP were replaced every hour PEG-IFN-alpha2a plasma levels remained constant throughout three experimental-HD-sessions, but PEG-IFN-alpha2b was cleared partially every BKP replacement. Porosity differ among high-flux dialysers. Neither PEG-IFN-alpha2a nor PEG-IFN-alpha2b were removed after three HD sessions through (27/31/33 A) pore size polysulphone dialysers. Although PEG-IFN-alpha2a was not cleared through middle pore-size (43 A/AN69ST) polyacrylonitrile dialyser, PEG-IFN-alpha2b was partially removed. CONCLUSIONS: The pharmacokinetics of Peg-IFN-alpha may vary in a patient on dialysis.

Antiviral Agents↗

PubMed2004

Ribozymes as antiviral agents.

Ribozymes are RNA molecules with cleavage activity that can be engineered to specifically target a given RNA molecule. The hammerhead, hairpin and hepatitis delta virus ribozymes have been widely studied for their use as therapeutical agents. This review discusses the structure and properties of these ribozymes, along with the advances made in the development of these molecules for their application in the treatment of hepatitis B, hepatitis C and human immunodeficiency virus infections.

Antiviral Agents↗

PubMed2004

[Guidelines on hemodialysis-associated viral infections].

The viric infections influence morbi-mortality in Chronic kidney Disease patients in hemodialysis therapy and can affect to the Staff of the Units. The guides considered the most relevant virus at the present moment: C Virus, B Virus and HIV. To prevent horizontal nosocomial transmission is necessary the observance always the universal precautions in the HD units, although sometimes can appeared seroconversions and epidemic bud when exist a break of these. Is analyzed different situations with special focus in units for acute patients. The following steps under the suspicious of the epidemic bud appeared in one of the annexes together with legislation according to this case. Respect to the staff in every one of the virus is shown prevention patterns, serologic markers to perform when an accident with infected blood occur, also is considered when treatment is indicated. The guides considered too the conditions necessary for include these patients on waiting list for kidney transplantation.

Ambulatory Care Facilities↗

PubMed2002

Present treatment expectations and risks of chronic hepatitis C.

During recent years, the treatment of chronic hepatitis C has increased in efficacy. Initially, the only approved treatment for this disease was interferon-alpha (IFN-alpha) monotherapy, achieving a 15% rate of sustained response. Subsequently, a combination of IFN-alpha plus ribavirin showed a greater efficacy: up to 40% success with 3 MU of IFN-alpha three times weekly and 1000-1200 mg of ribavirin daily in naive patients and in those who had relapsed after a course of IFN-alpha therapy. Pegylated interferon (PEG-IFN), due to its better efficacy and tolerance, has displaced the use of recombinant IFN. Nevertheless, the sustained response rate mainly depends on HCV RNA load and HCV genotype. Presumably, in future, new strategies based on gene therapy will play an important role in the treatment of chronic hepatitis C.

Antiviral Agents↗

PubMed2002

In vitro infection of human peripheral blood mononuclear cells by a defective hepatitis B virus with a deletion in the PreS1 region of the viral genome.

Previously, we identified a defective hepatitis B virus (HBV) which contains a 183 nucleotide deletion in the PreS1 region of the viral genome affecting the S gene promoter in sera from hepatitis B surface antigen (HBsAg)-negative patients with serum HBV-DNA. The aim of this study was to analyse the infectivity of this mutant. Peripheral blood mononuclear cells (PBMC) from a healthy donor were incubated with serum samples from 2 HBsAg-negative patients with serum HBV-DNA (infected with wild-type and deletion mutant HBV), from an HBsAg carrier (infected with wild-type HBV) and from a healthy donor. After 1 week, HBV-DNA was detected by polymerase chain reaction (PCR) in all supernatants and cells incubated with the HBV-DNA-positive inocula. DNase and trypsin pretreatment confirmed intracellular localization of HBV-DNA in cells. HBV-RNA and covalently closed circular HBV-DNA were also detected in PBMC, indicating that the viral DNA infecting these cells was transcriptionally active. Deletion mutant and wild-type HBV were detected in the supernatants and cells infected with the two HBsAg-negative sera, while only wild-type HBV was detected in the supernatant and cells incubated with the serum from the HBsAg-carrier. In conclusion, this HBV deletion mutant can infect, replicate and release viral particles in in vitro infected PBMC.

Cells, Cultured↗

PubMed2001

Distribution of hepatitis C virus infection in liver biopsies from children and adults with chronic hepatitis C.

Chronic hepatitis C in children is characterized by milder forms of liver damage than those found in adults. Such a difference has been attributed to a low viral load in children that may lead to poor recognition of infected cells by the immune system. One approach that could be used to confirm this hypothesis may be to examine the number of infected hepatocytes in liver biopsies. Paraffin embedded liver biopsies from 21 children and 15 adults with chronic hepatitis C virus (HCV) infection (with a similar duration of the infection) were hybridized in situ and the percentage of infected hepatocytes was correlated with the histological activity index, alanine aminotransferase levels and HCV viraemia levels. Histological activity index and HCV viraemia levels were statistically higher (P < 0.05 and P < 0.01 respectively) in adults than in children, and the percentage of infected hepatocytes was higher in adults (11.0 +/- 19.7%) than in children (4.6 +/- 3.6%), although it did not reach statistical significance. Also, the percentage of infected hepatocytes correlated with HCV-RNA concentration in serum in both children (r = 0.683, P = 0.001) and adults (r = 0.768, P = 0.001). The results show that liver damage in children with chronic hepatitis C is not related to the extent of infection in the liver. This findings support the hypothesis of that liver injury in chronic HCV infection is mediated by the host immune response.

Adult↗

PubMed2001

TT virus detection in oral lichen planus lesions.

Epidemiological studies have demonstrated a correlation between oral lichen planus and different liver diseases. The new virus termed TT virus (TTV) is highly prevalent in patients with chronic hepatitis of different etiology and it may be speculated that TT virus may be involved in the pathogenesis of oral lichen planus. This study examined the presence of TT virus DNA in serum by PCR and in oral mucosa biopsies by in situ hybridization from 20 patients with oral lichen planus (13 with chronic hepatitis and seven without liver disease). Serum and oral mucosa biopsies from six patients all with chronic hepatitis with leukoplakia were also studied as controls. TT virus DNA was positive in the serum of 17/20 (85%) of the patients with oral lichen planus and in all the controls. TT virus DNA hybridization signals were detected in mucosa biopsies from all the patients with TT virus DNA in serum but in none of the three cases without this marker. The percentage of positive cells ranged from 1.6-80%. No differences were found in the percentage of positive cells between TT virus positive patients with and without oral lichen planus and there was no relationship between the number of positive cells and the intensity of the inflammatory infiltrate. In conclusion, TT virus infects oral epithelial cells but the results do not support a role for TT virus in causing oral lichen planus.

Aged↗

PubMed2001

Multicenter randomized study comparing initial daily induction with high dose lymphoblastoid interferon vs. standard interferon treatment for chronic hepatitis C.

One hundred fifty-five chronic hepatitis C patients were assigned at random to receive natural lymphoblastoid interferon (IFN)alpha-n1, s.c., for 13 months in one of three treatment regimens: initial daily induction with 10 million units (MU) followed (group 1, n = 50) or not (group 2, n = 52) by 1 month of rest and then three times weekly 10 MU (2 months), 5 MU (2 months), and 3 MU (8 months); group 3 (n = 53) received tiw 5 MU (2 months) followed by 3 MU (11 months). By intention-to-treat analysis, ALT normalization at completion of treatment was greater in patients who received continuous IFNalpha-n1 therapy with initial daily induction (group 2: 24/52, 46%) compared with those given intermittent therapy with initial daily induction (group 1: 17/50, 34%) and those who received standard IFNalpha-n1 therapy (group 3, 18/53, 34%; P not significant). The sustained ALT response was 26%, 27% and 21% and the sustained virological response was 20%, 27%, and 19%, in groups 1, 2, and 3, respectively. A trend was observed towards a higher biochemical and virological end-of-treatment response in patients given induction therapy (17%) compared with standard therapy (6%, P = 0.053). Sustained biochemical and virological responses were 20%, 27%, and 17% in groups 1, 2, and 3, respectively. Platelet and leukocyte counts decreased following daily high-dose treatment and remained low until therapy cessation (P < 0.001). The data suggest that daily s.c. induction with 10 MU IFNalpha-n1 followed by intermittent or continuous maintenance therapy for 1 year does not improve the results achieved with the standard 1-year IFNalpha course in the treatment of chronic hepatitis C patients.

Adolescent↗

PubMed2001

In situ detection of hepatitis C virus RNA in salivary glands.

Chronic hepatitis C virus (HCV) infection has been associated with several extrahepatic manifestations, among these, to diseases with oral manifestations such as Sjögren's syndrome or sialadenitis. HCV-RNA has been detected in saliva and in salivary glands from patients with sialadenitis by polymerase chain reaction. However, morphological evidence of HCV replication in salivary gland cells is needed to support a role for HCV in causing sialadenitis or Sjögren's syndrome. We have used in situ hybridization and immunohistochemistry to analyze the presence of HCV-RNA of sense and antisense polarity and HCV core antigen, respectively, in salivary gland biopsies from 19 patients with chronic sialadenitis or Sjögren's syndrome (eight anti-HCV-positive; 11 anti-HCV-negative). HCV-RNA of both positive and negative polarity as well as HCV core antigen were detected in the epithelial cells of the salivary gland biopsies from all of the anti-HCV-positive patients but in none of the anti-HCV-negative cases. The percentage of HCV-infected cells ranged from 25 to 48.8% in the patients studied. In conclusion, we have shown that HCV infects and replicates in the epithelial cells from salivary glands of patients with Sjögren's syndrome or chronic sialadenitis. However, its implication in the pathogenesis of these diseases deserves future research.

Adult↗

PubMed2001

Extended follow-up of anti-HBe-positive patients with chronic hepatitis B retreated with ribavirin and interferon-alpha.

In a pilot study of combination therapy with ribavirin and IFN alpha conducted in anti-HBe-positive individuals with chronic hepatitis B, 21% of patients achieved a sustained ALT normalization and clearance of hepatitis B virus (HBV) DNA as measured by PCR. The present work has assessed whether these sustained responses are lasting long-term. In addition, IFN gamma levels were tested serially in serum as a measure of the immune system activation during treatment. By extending the post-treatment follow-up period 2 years the occurrence of delayed HBV DNA relapses was observed. A low serum level of IFN gamma was detected during and after treatment. IFN gamma demonstrated a multiphasic time-course: the amount of IFN gamma increased in parallel with reductions in HBV DNA but also with ALT flare-ups. In conclusion, the extended follow-up study of anti-HBe-positive patients after combined treatment with ribavirin and IFN alpha has shown that sustained responses are lasting in 17% patients but also that a late onset HBV DNA relapse may occur.

Adult↗

PubMed2001

Interleukin-12 in the treatment of chronic hepatitis B and C.

Interleukin-12 plays a central role in mounting an effective cellular immune response directed towards elimination of intracellular pathogens. In two open label, multicenter, dose-escalation phase I/II studies tolerability, pharmacokinetics, pharmacodynamics, and efficacy of subcutaneously administered recombinant human interleukin-12 (rHuIL-12) was assessed in the treatment of chronic hepatitis B and C. Forty-six patients with chronic hepatitis B and 60 patients with chronic hepatitis C were treated for 12 and 10 consecutive weeks, respectively. rHuIL-12 was generally well tolerated, but was associated with temporary decreases in neutrophils and lymphocyte counts, and with elevations in serum transaminases and bilirubin. Serum IL-12 levels observed were higher at 0.5 microg/kg compared with 0.25 microg/kg doses, suggesting a dose-related increase in systemic exposure of IL-12. Measurable levels of interferon-gamma were also observed at the highest dose of 0.5 microg/kg. At the end of treatment HBV DNA clearance was greater in patients treated with 0.50 microg/kg (25%) or with 0.25 microg/kg (13%) compared with those given 0.03 microg/kg. In patients with chronic hepatitis C, HCV RNA remained detectable in all patients. A more than 50% decrease in pretreatment HCV RNA levels was observed in 3/16 patients (0.03 microg/kg), in 3/14 (0.10 microg/kg), in 6/15 (0.25 microg/kg), and in 8/15 patients of the 0.5 microg/kg dose group. In conclusion, antiviral activity of rHuIL-12 in patients with chronic hepatitis B or C does not appear to be advantageous in comparison to other currently available treatments.

Adolescent↗

PubMed2001

Hepatitis B virus-specific T-cell proliferation and cytokine secretion in chronic hepatitis B e antibody-positive patients treated with ribavirin and interferon alpha.

Immune elimination of hepatitis B virus (HBV) during antiviral therapy depends on the activation of T-cell responses, which are generally impaired in chronic hepatitis B. HBV-specific T helper (Th)-cell reactivity has been assessed post-treatment in liver and peripheral blood of 18 anti-HBe-positive patients with chronic hepatitis B administered combined ribavirin/interferon alfa (IFN-alpha) therapy. The results showed that patients with undetectable HBV DNA by quantitative polymerase chain reaction under combination therapy were able to mount an HBV-specific CD4(+) Th-cell proliferative response and such T-cell reactivity is detectable 1 year after HBV DNA clearance. Hepatitis B virus core (HBcAg) and e (HBeAg) antigen-specific Th-cell proliferation was found more frequently in the liver and peripheral blood in those patients who sustained the alanine aminotransferase (ALT) normalization together with HBV DNA loss. However, HBV-specific IFN-gamma production in vitro in peripheral blood mononuclear cells augmented in 4 of 5 sustained responders and all 13 nonresponders, interleukin 10 (IL-10) production decreased in all 5 sustained responders but increased in 7 of 13 nonresponders. Furthermore, intrahepatic HBcAg plus HBeAg-specific Th-cell proliferation only occurred in sustained responders (2 of 3, 67%, vs. 0 of 9; P =.045) whose cells showed in vitro significantly increased productions in HBcAg/HBeAg-specific IFN-gamma and IL-12 compared with nonresponders in whom IFN-gamma and IL-12 productions decreased together with increased IL-10 secretion. In conclusion this study indicates that combined therapy with ribavirin and IFN-alpha for chronic hepatitis B not only significantly reduces viremia levels but also induces lasting CD4(+) T-cell proliferation and Th1 cytokine release at the site of infection, which may lead to sustained eradication of the HBV.

Adult↗

PubMed2001

Expression of factor VII in the liver of patients with liver disease: correlations with the disease severity and impairment in the hemostasis.

Factor VII (FVII) plasma levels in patients with liver disease may be below the normal range. However, no data are available on FVII expression in liver biopsies from patients with liver diseases other than cirrhosis. We have analyzed the expression of FVII by in situ hybridization in liver biopsies from 50 patients in comparison with the procoagulant activity of FVII, and with the plasma levels as activated FVII (FVIIa) and FVII antigen. The level of FVIIa was significantly lower in stage 4 liver fibrosis patients than in the remaining ones (P < 0.05). The percentage of hepatocytes expressing FVII was significantly lower in stage 4 liver fibrosis patients (4.1+/-1.3%) than in stage 3 (22.7+/-6.1%), stage 2 (31.5+/-6.1%), stage 1 (43.7+/-8.2%) and stage 0 patients (63.8+/-4.4%) (P < 0.001). These percentages correlated inversely in a statistically significant way with the histological activity index and the liver function tests. We have demonstrated that the FVIIa plasma levels in patients with chronic liver disease other than cirrhosis may be below the normal range in the absence of blood coagulation impairment. The percentage of hepatocytes expressing FVII decreases as the severity of liver damage increases.

Adult↗

PubMed2001

Association of HLA-DR genes with mild idiopathic adulthood biliary ductopenia.

OBJECTIVE: Mild idiopathic adulthood ductopenia (MIAD) is an asymptomatic chronic cholestatic liver disease characterized by the loss of interlobular bile ducts in <50% of the portal tracts. Although the underlying cause of MIAD is unknown, the host factors may contribute to the patient's susceptibility to the disease. The aim of this work was to investigate the immunogenetics in the pathogenesis of MIAD. METHODS: We prospectively studied 22 Caucasian patients with MIAD. Peripheral blood was collected, and HLA-DR typing was performed by polymerase chain reaction with sequence-specific primers followed by sequencing for subtyping. Results were compared with those from 140 age- and sex-matched controls. RESULTS: There was no significant association between HLA-DRB1 alleles and the disease, although a trend was found in MIAD patients with the DRB1*1502 allele (five of 44 vs four of 280 in controls; p corrected = 0.055; chi2 = 13.9). Multiple HLA-DRB1 alleles (*04, *11, *15) showed increased frequencies in MIAD patients. Further subtyping revealed a motif (positions 25-32 of the beta1 chain) present in 17 (77.3%) patients, which was significantly associated with MIAD (p = 0.049; chi2 = 3.87). Seven patients (31.8%) and 21 (15%) controls coded for this motif in their two alleles (p = 0.068; chi2 = 3.76). Among MIAD patients, those seven had abnormal ALT levels (p = 0.017) and their gamma-glutamyltransferase and ALT values tended to be more increased. CONCLUSIONS: These results provide evidence of an immunogenetic basis of susceptibility to MIAD in Caucasian individuals.

Adult↗