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Biomedical subjects

P Opolon

Publications and source records attributed to P Opolon.

At least 37 records · Page 2Linked to original sources

Recombinant adenovirus shedding after intratumoral gene transfer in lung cancer patients.

We conducted two phase 1 trials of direct intratumoral injection of a recombinant E1E3-deleted adenovirus (AdR) encoding either the bacterial enzyme beta-galactosidase (Ad.RSVbetagal) or interleukin 2 (IL2, AdTG5327) into primary nonsmall-cell lung cancers of 21 patients. We report here virus shedding and the duration of virus expression in the tumor after intrabronchial injection of 10(7), 10(8) or 10(9) PFU of adenovirus. The infectious AdR and the viral DNA were detected in PBL, plasma, stool and aerodigestive samples in a dose-dependent manner, since cell cultures and PCRs were found to be positive mainly for samples from patients who received the highest AdR dose (10(9) PFU). We detected beta-galactosidase activity in the tumor biopsy samples of 66% of the patients, seemingly dose related, and only low levels of IL2 mRNA could be detected in tumor biopsy samples. E1 sequences were not detected by PCR in any of the PBL and bronchial samples collected after virus delivery, except in one patient. In this patient, E1 sequences were detected in PBL as well as in tumor biopsy samples collected at days 8, 30 and 60 and were correlated with longer beta-galactosidase expression in tumor samples. PBL tested before and after virus delivery contained both E1 sequences indicating that they did not result from replication-competent adenovirus (RCA) E1 sequences present in the inoculum. In addition, only on the day of the injection was Ad.RSVbetagal also detected in E1-positive PBL, indicating that virus replication in blood was very unlikely.

Adenoviridae↗

Interferon for acute hepatitis C.

BACKGROUND: Acute hepatitis C virus (HCV) infection progresses to chronicity in the majority of patients. In order to prevent the progression to chronic disease, several studies have assessed interferon in patients with acute hepatitis C. OBJECTIVES: The aim of this review was to assess the efficacy of interferon in acute HCV infection. SEARCH STRATEGY: We searched MEDLINE, the Cochrane Controlled Trials Register, and the abstracts of the American Association for the Study of Liver Diseases (June 2001). We also contacted pharmaceutical companies to obtain unpublished trials. SELECTION CRITERIA: Randomised clinical trials comparing interferon with placebo or no treatment, and published as an article, abstract, or letter were selected. No language limitations were used. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. The following endpoints were analysed: normalization of alanine aminotransferase (ALT) activity at the end of treatment (biochemical ETR); sustained ALT normalization at the end follow-up (biochemical SR); disappearance of serum HCV RNA by polymerase chain reaction assay at the end of treatment (virologic ETR) and at the end of follow-up (virologic SR). Histologic data and adverse events were also recorded. Assessment of drug efficacy used the methods of Peto and Der Simonian and Laird. MAIN RESULTS: Six randomised trials involving 206 patients with acute hepatitis C met the inclusion criteria. Four trials assessing interferon alfa-2b in 141 patients, all with transfusion-acquired acute hepatitis C, were included. They demonstrated no significant heterogeneity in the outcomes assessed. When compared with no treatment, interferon alfa-2b was associated with an increase in the rates of virologic ETR and SR by 45% (95% CI 31-59%, P < 0.00001) and 29% (95% CI 14-44%, P = 0.0002), respectively. The virologic ETR was 42% (95% CI: 30-56%) in the interferon alfa-2b group versus 4% (95% CI 0-13%, P < 0.00001) in the control group. At the end of follow-up, a virologic SR was seen in 32% (95% CI 21-46%) of interferon-treated patients versus only 4% (95% CI 0-13%, P = 0.00007) of controls. The tolerability of therapy, or the impact of interferon alfa-2b on hepatic histology, was not reported. Two trials assessed interferon beta in a total 65 patients. The efficacy of interferon beta could not be assessed, however, due to heterogeneity of these trials. REVIEWER'S CONCLUSIONS: Interferon alfa is effective in improving biochemical outcomes and achieving sustained virologic clearance in patients with transfusion-acquired acute hepatitis C. The effect on long-term clinical outcomes could not be assessed due to limitations in the current data.

Acute Disease↗

Interferon for interferon naive patients with chronic hepatitis C.

BACKGROUND: A previous meta-analysis of interferon therapy in naive patients with chronic hepatitis C has documented its efficacy in achieving virologic clearance, and improving liver biochemistry and histology; however, since its publication additional trials have been reported. OBJECTIVES: To evaluate the response to interferon in interferon naive patients with chronic hepatitis C. The effect of treatment dose and duration, and the response in patients with cirrhosis and those with normal aminotransferases was also investigated. SEARCH STRATEGY: The Cochrane Controlled Trials Register (Cochrane Library Issue 1, 1999), MEDLINE (January 1966 to December 1999), and reference lists were searched, and pharmaceutical companies were contacted for unpublished trials. SELECTION CRITERIA: Randomised clinical trials comparing interferon with placebo, no treatment, or different regimens of interferon were selected. Abstracts were excluded. DATA COLLECTION AND ANALYSIS: The primary outcome measure was sustained disappearance of serum HCV RNA (virologic sustained response (SR)). Biochemical and end of treatment responses, liver histology, and adverse events were also recorded. Assessment of drug efficacy used the methods of Peto and Der Simonian and Laird. MAIN RESULTS: Fifty-four trials enrolling 6545 patients were included. Compared with no treatment, interferon 3 MU thrice weekly for 12 months increased the probability of a virologic SR (Peto odds ratio (OR) 4.60; 95% confidence interval (CI) 1.53 to 13.85). At this dosage and duration of therapy, the rate of virologic SR was 17% (95% CI 10 to 28%) in interferon-treated patients versus 3% (95% CI 1 to 10%) in controls. A dose of 6 MU was more effective than 3 MU thrice weekly (OR for 12 months treatment, 2.21; 95% CI 1.10 to 4.45), as were durations of 12 months or greater versus six months (OR 1.87; 95% CI 1.30 to 2.67). Adverse events were more common with higher doses and prolonged durations of treatment. Compared with no therapy, interferon increased the probability of histologic improvement (OR 9.22; 95% CI 5.69 to 14.94). The response to interferon in cirrhotic patients (virologic SR, 17%; 95% CI 11 to 26%) was similar to that in non-cirrhotic patients. However, interferon was no more effective than control in patients with normal aminotransferases. REVIEWER'S CONCLUSIONS: Interferon is effective in achieving viral clearance and improving liver biochemistry and histology in interferon naive patients with chronic hepatitis C. Higher doses and prolonged durations are more effective, but associated with more frequent adverse events. Interferon is associated with similar benefits in patients with cirrhosis, but the efficacy in patients with normal aminotransferases is unproven.

Antiviral Agents↗

Adenovirus-mediated gene transfer of urokinase plasminogen inhibitor inhibits angiogenesis in experimental arthritis.

Plasmin is essential for metalloproteases activation, endothelial cell migration and degradation of the extracellular matrix. The process is common to neoangiogenesis pannus formation and cartilage degradation within arthritic joints. Since 80% of synovial cells express urokinase plasminogen activator receptor (uPAR), we investigated the inhibition of plasmin activation in a collagen-induced arthritis (CIA) mice model, by expressing a uPA/uPAR antagonist molecule (ATF) fused to human serum albumin (HSA) to extend its serum half-life. Overexpression was obtained with an adenoviral vector expressing the chimeric murine ATF-HSA. We showed that the genetic coupling did not significantly reduce the ability of the ATF moiety to interact with its receptor uPAR. The chimeric protein was detectable in the sera of injected mice 7 days following Ad-mATF-HSA injection, then decreased in parallel with the anti-HSA titer increase. Systemic Ad-mATF-HSA injection performed on day 25 following CIA induction decreased the incidence of arthritis and the severity of the disease. Moreover, synovial angiogenesis in arthritic paws was decreased after Ad-mATF-HSA gene transfer, as assessed by smooth muscle actin immunostaining. The preventive effect observed on arthritis was related to the decrease in angiogenesis, rather than inhibition of extracellular matrix degradation.

Adenoviridae↗

Flumazenil vs. placebo in hepatic encephalopathy in patients with cirrhosis: a meta-analysis.

BACKGROUND: Randomized controlled trials testing flumazenil in hepatic encephalopathy have shown conflicting results. AIM: To compare flumazenil and placebo in hepatic encephalopathy in patients with cirrhosis. METHODS: An overview of randomized controlled trials comparing flumazenil and placebo in hepatic encephalopathy in patients with cirrhosis was performed. For each end-point, heterogeneity and treatment efficacy were assessed by Peto and Der Simonian methods. As most trials were crossover in nature, a sensitivity analysis was performed including the two treatment periods. RESULTS: Six double-blind randomized controlled trials, including 641 patients (326 treated with flumazenil and 315 with placebo), were identified. The treatment duration ranged from 5 min to 3 days. Heterogeneity tests between control groups were not significant. The mean percentages of patients with clinical improvement (five trials) were 27% in treated groups and 3% in placebo groups. This difference was significant by both methods (Peto: odds ratio=6.15; 95% confidence interval, 4.0-9.5; P < 0.001; Der Simonian: mean rate difference, 29%; 95% confidence interval, 17-41; P < 0.001). The mean percentages of patients with electroencephalographic improvement were 19% in treated groups and 2% in placebo groups. This difference was significant only with the Peto method (odds ratio=5.8; 95% confidence interval, 3.4-9.7; P < 0.001). The sensitivity analysis showed similar results. CONCLUSIONS: This meta-analysis shows that flumazenil induces clinical and electroencephalographic improvement of hepatic encephalopathy in patients with cirrhosis.

Coma↗

A constellation of cardiovascular risk factors is associated with hepatic enzyme elevation in hyperlipidemic patients.

Abnormal circulating levels of hepatic enzymes are frequently found in subjects displaying hyperlipidemia or obesity or both. At present, there is a paucity of information on the principal cardiovascular risk factors that are associated with elevated plasma levels of hepatic enzyme activity in hyperlipidemic patients. We analyzed the potential relationships between serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma glutamyl transferase (GGT) and cardiovascular and metabolic risk factors in a cohort of 8,501 men and women referred to our outpatient clinic for hyperlipidemia by their general practitioner. In this cohort, 27.6% of patients displayed serum levels of ALT above the upper limit of normal values. Both men and women who exhibited ALT levels superior to the upper limit of the normal range had elevated systolic (SBP) and diastolic blood pressure (DBP), body mass index (BMI), alcohol intake, and serum levels of blood glucose, uric acid, total cholesterol, and triglycerides (P <.0035 for all parameters). In a multivariate analysis, BMI, uric acid, and blood glucose remained significantly associated with ALT levels in men and women. We conclude that cardiovascular and metabolic features characterizing the plurimetabolic syndrome, including serum uric acid levels, are associated with significant elevation of hepatic enzyme activities. Because these abnormalities may not only be reversible but also associated with a poor prognosis, further studies are needed to identify those dyslipidemic patients who are at risk for the development of severe hepatic tissue damage.

Adult↗

AdTIMP-2 inhibits tumor growth, angiogenesis, and metastasis, and prolongs survival in mice.

TIMP-2 is a natural matrix metalloproteinase (MMP) inhibitor that prevents the degradation of extracellular matrix proteins. It abolishes the hydrolytic activity of all activated members of the metalloproteinase family and in particular that of MT1-MMP, MMP-2, and MMP-9, which are selective for type IV collagenolysis. Since MMPs have been implicated in both cancer progression and angiogenesis, we generated a recombinant adenovirus to deliver human TIMP-2 (AdTIMP-2) and evaluated its anticancer efficiency in three murine models. Our results demonstrated that overexpression in vitro of TIMP-2 inhibited the invasion of both tumor and endothelial cells without affecting cell proliferation. Its in vivo efficiency has been evaluated in murine lung cancer LLC, and colon cancer C51 in syngeneic mice as well as in human breast cancer MDA-MB231 in athymic mice. Preinfection of tumor cells by AdTIMP-2 resulted in an inhibition of tumor establishment in more than 50% of mice in LLC and C51 models and in 100% mice in the MDA-MB231 model. A single local injection of AdTIMP-2 into preestablished tumors of these three types significantly reduced tumor growth rates by 60--80% and tumor-associated angiogenesis index by 25--75%. Lung metastasis of LLC tumor was inhibited by >90%. In addition, AdTIMP-2-treated mice showed a significantly prolonged survival in all the cancer models tested. These data demonstrate the potential of adenovirus-mediated TIMP-2 therapy in cancer treatment.

Adenoviridae↗

BRCA1 carries tumor suppressor activity distinct from that of p53 and p21.

The loss of BRCA1 function appears as an essential step in breast and ovarian epithelial cells oncogenesis and is consistent with the concept that BRCA1 acts as a tumor suppressor gene. However, the mechanism underlying this activity is not understood. In 1996, a retroviral vector was used for BRCA1 delivery to demonstrate that the transfer of BRCA1 inhibits breast and ovarian cancer cell growth. Since this early observation, the tumor growth inhibitory activity of BRCA1 in vivo has not been further documented. Here we re-address this issue and report experiments designed to evaluate the potential of adenovirus-mediated BRCA1 delivery to suppress the growth of cells with various status of endogenous BRCA1 in comparison with p53 and p21. Delivery of wild-type BRCA1 by an adenovirus vector in breast and ovarian tumor cells, decreases in vitro proliferation and tumorigenicity. Similarly, in vivo administration of BRCA1 provokes tumor growth retardation or regression comparable to that obtained with p53 or p21. The antitumor effect of BRCA1 is not observed upon transfer of a mutant lacking the 542 C-terminal residues. The p53- or p21-mediated antiproliferative activities are likely to bear on their capacity to induce apoptosis and/or interfere with cell cycle checkpoint. By contrast, the data presented here show that neither of these mechanisms can account for the BRCA1-mediated antitumor activity and suggest the activation of an alternative route.

Adenoviridae↗

Meta-analysis of interferon randomized trials in the treatment of viral hepatitis C in naive patients: 1999 update.

The aim of this study was to update our previous meta-analysis of interferon (IFN) in the treatment of hepatitis C and to analyse new factors, namely, HCV RNA end-point, patients with cirrhosis and patients with normal ALT. We use the Der Simonian and Laird method, with heterogeneity and sensitivity analyses. Seventy-six randomized control trials (RCTs) in naive patients were found but we focused our analysis on 59 RCTs with chronic hepatitis C (26 vs. controls and 33 comparing different regimens) and on seven RCTs in acute hepatitis. Interferon-alpha (IFN-alpha) at 3 MU thrice weekly (TIW) for 12 months exhibited 39% of virological end-of-treatment response (ETR) and 17% of virological sustained response (SR), respectively, vs. 1% and 3% in untreated controls (all P < 0.001). There was a significant dose effect (in favour of 6 vs. 3 MU TIW): the virological SR at 6 months were 35% in the 6 MU group (95% CI: 24-47) and 16% in the 3 MU group (95% CI: 8-27) and were at 12 months 43% in the 6 MU group (95%CI: 31-56) and 25% in the 3 MU group (95% CI: 16-37). There was a significant duration effect (12 vs. 6 months) upon the virological SR rate both at 3 and 6 MU: 3 MU provided 14% of virological SR (95% CI: 11-19) in the 12 months group vs. 7% (95% CI: 5-11) in the 6 months group and 6 MU provided 22% (95% CI: 17-29) and 16% (95% CI: 11-22) virological SR in the 12 and 6 months groups, respectively. Cirrhotic treated patients had 17% of virological SR (95 CI: 9-24%; P < 0.001) vs. 0% in controls and provided a 20% reduction rate (95 CI: -2% to -37%, P=0.03) in hepatocellular carcinoma incidence. In acute hepatitis C, a 3-month treatment with IFN-alpha showed significant efficacy vs. controls upon the virological SR rate (32% vs. 4%, P < 0.001). In conclusion, we confirm the dose and duration effect of IFN in chronic hepatitis C, and the efficacy of IFN-alpha in the treatment of acute hepatitis and in cirrhotic patients.

Acute Disease↗

Evaluation of contrast-enhanced color Doppler ultrasound for the quantification of angiogenesis in vivo.

RATIONALE AND OBJECTIVES: To evaluate contrast-enhanced color Doppler ultrasonography (CDUS) aimed at quantifying angiogenesis in vivo. METHODS: Eight colon tumors xenografted into mice were studied with CDUS both without and after injection of SHU 508A. The number of intratumor vessels and pedicles visualized with CDUS and the value of the acoustic intensity quantified by computer were compared with the evaluation of angiogenesis by study of digitized histological slides. RESULTS: SHU 508A increased the number of intratumor vessels and pedicles depicted by CDUS, which could also be quantified by acoustic intensity. The comparison of CDUS and digitized histological slide studies showed that the detection threshold after SHU 508A administration allowed visualization of small vessels (40 microm in diameter). The "hot spots" seen on histology were superimposable onto vessels seen with CDUS. Regions in which no vessels were detected by CDUS corresponded to regions in which vascularization was absent by histological analysis. CONCLUSION: Injection of SHU 508A significantly increased vessel detection with CDUS.

Animals↗

Focal neurological signs in hepatic encephalopathy in cirrhotic patients: an underestimated entity?

OBJECTIVES: Focal neurological signs have been poorly documented in the course of hepatic encephalopathy in cirrhotic patients because they are not mentioned in any textbooks of liver diseases. Having the opportunity to observe such cases, we underwent a prospective study to determine incidence, characteristics, associated factors, prognostic significance, and outcome of this rare form of hepatic encephalopathy. METHODS: Over a 12-month period, all cirrhotic patients hospitalized in the intensive care unit of our department for hepatic encephalopathy were prospectively studied. Patients with clinical and electroencephalogram evidences of hepatic encephalopathy were examined by a senior physician and, in cases of focal neurological signs, underwent examination by a neurologist, CT scan, lumbar punction, and cerebral magnetic resonance imaging and echo Doppler examination of neck and head vessels. Clinical and biological parameters were compared in patients during episodes with and without focal neurological signs, and outcome was noted. RESULTS: Thirty-four cirrhotic patients were hospitalized for 48 episodes of hepatic encephalopathy; two of these patients with cerebral hematoma were excluded. Twenty-four patients exhibited 38 hepatic encephalopathy episodes without focal neurological signs (82.6%), and eight patients exhibited eight hepatic encephalopathy episodes with focal neurological signs (17.4%) that were hemiplegia and hemiparesia in six patients (75%). In all patients, cerebral CT scan and cerebrospinal fluid examination disclosed no abnormalities, as neither did cerebral magnetic resonance imaging (n = 5) and echo Doppler examination of neck and head vessels (n = 5). Except for female sex, which was more often encountered in patients with focal neurological signs (p < 0.05), there were no differences between episodes with and without focal neurological signs for any of the parameters studied. In surviving patients who recovered from hepatic encephalopathy (7/8), focal neurological signs disappeared without recurrences after follow up of 6 months (3-12). CONCLUSIONS: Hepatic encephalopathy with focal neurological signs when carefully searched is not uncommon. It could be more frequent in cirrhotic females, is reversible, and has no prognostic significance.

Case-Control Studies↗

Adenovirus-mediated transfer of the thyroid sodium/iodide symporter gene into tumors for a targeted radiotherapy.

The Na+/I- symporter (NIS) present in the membranes of thyroid cells is responsible for the capacity of the thyroid to concentrate iodide. This allows treatment of thyroid cancers with 131I. We propose to enlarge this therapeutic strategy to nonthyroid tumors by using an adenoviral vector to deliver the NIS gene into the tumor cells. We constructed a recombinant adenovirus encoding the rat NIS gene under the control of the cytomegalovirus promoter (AdNIS). Infection of SiHa cells (human cervix tumor cells) with AdNIS resulted in perchlorate-sensitive 125I uptake by these cells to a level 125-225 times higher than that in noninfected cells. Similar results were obtained for other human tumor cell lines, including MCF7 and T-47D (mammary gland), DU 145 and PC-3 (prostate), A549 (lung), and HT-29 (colon), demonstrating that the AdNIS vector can function in tumor cells of various origins. In addition, AdNIS-infected tumor cells were selectively killed by exposure to 131I, as revealed by clonogenic assays. To assess the efficiency of this cancer gene therapy strategy in vivo, we injected the AdNIS vector in human tumors (SiHa or MCF7 cells) established s.c. in nude mice. Immunohistological analysis confirmed the expression of the NIS protein in the tumor. Three days after intratumoral injection, AdNIS-treated tumors could specifically accumulate 125I or 123I, as revealed by kinetics and imaging experiments. A quantitative analysis demonstrated that the uptake in AdNIS-injected tumors was 4-25 times higher than that in nontreated tumors. On average, 11% of the total amount of injected 125I could be recovered per gram of AdNIS-treated tumor tissue. Altogether, these data indicate that AdNIS is very efficient in triggering significant iodide uptake by a tumor, outlining the potential of this novel cancer gene therapy approach for a targeted radiotherapy.

Adenoviridae↗

Combined effects of radiotherapy and angiostatin gene therapy in glioma tumor model.

The objective of the present study was to evaluate the antitumor effect of a defective adenovirus expressing a secretable angiostatin-like molecule (AdK3) in combination with radiotherapy in rat C6 gliomas s.c. preestablished into athymic mice. In vitro, the combination regimen was significantly (P < 0.001) more cytotoxic for human microcapillary endothelial cells than either treatment alone, whereas survival of C6 glioma cells was not affected in the conditions used. Radiotherapy and AdK3 gene delivery was then studied on well established C6 xenografts (165 +/- 70 mm(3)). In these tumors, AdK3 intratumoral injections had only a marginal effect. Interestingly, when experimental radiotherapy was added, significantly higher (P < 0.005), and possibly synergistic, antitumoral effects were observed that tightly correlated a marked decrease of intratumoral vascularization. The combination of radiotherapy and AdK3 intratumoral injections also revealed a significant (P < 0.05) inhibition of tumor growth as compared with either treatment alone for larger tumors (467 +/- 120 mm(3)). Altogether, these data emphasize the potential of combining a destructive strategy directed against the tumor cells with an anti-angiogenic approach to fight cancer.

Adenoviridae↗

Liver fibrosis in overweight patients.

BACKGROUND & AIMS: A common clinical issue is whether overweight patients with abnormal liver function test results should undergo liver biopsy. Although serious liver injury can occur, its prevalence and risk factors are not well known. METHODS: Ninety-three consecutive patients with abnormal liver function tests (but without overt liver disease), body mass index (BMI) > 25 kg/m(2), and no alcoholic, viral, autoimmune, drug-induced, or genetic liver disease were retrospectively studied. Clinical, biological, and histological variables were tested for association with septal fibrosis or cirrhosis. RESULTS: Septal fibrosis was present in 28 patients (30%) including cirrhosis in 10 (11%). Age >/= 50 years (odds ratio [OR], 14.1), BMI >/= 28 kg/m(2) (OR, 5.7), triglycerides >/= 1.7 mmol/L (OR, 5), and alanine aminotransferase (ALT) >/= 2N (OR, 4.6) were independently associated with septal fibrosis. Among histological features, septal fibrosis was strongly associated with necroinflammatory activity (OR, 44). A score combining age, BMI, triglycerides, and ALT had 100% negative predictive value for septal fibrosis when scoring 0 or 1 (100% sensitivity for a specificity of 47%). CONCLUSIONS: Septal fibrosis occurs frequently in overweight patients with abnormal liver function tests. A clinicobiological score combining BMI, age, ALT, and triglycerides could improve selection of patients for liver biopsy.

Adult↗

Impact of human immunodeficiency virus infection on the histological features of chronic hepatitis C: a case-control study. The MULTIVIRC group.

Hepatitis C virus (HCV) is frequently encountered in human immunodeficiency virus (HIV)-infected patients because of common routes of transmission. Previous studies suggested that HIV infection impaired the natural course of chronic hepatitis C, with a more rapid progression to cirrhosis. However, these studies did not assess the HIV infection impact on chronic hepatitis C by taking into account the risk factors for liver fibrosis progression: alcohol, sex, age at the contamination, and duration of HCV infection. We studied liver biopsy specimens of 2 groups of 58 patients that were infected by both HCV and HIV or by HCV alone. The 2 groups were matched according those risk factors, and liver biopsy responses were evaluated with the METAVIR items. The METAVIR activity was higher in HIV-positive than HIV-negative patients. Cirrhosis was more frequent: (1) in HIV-positive patients with CD4 < or = 200 cells/microL (45%) than in HIV-negative patients (10%) (P = .003), (2) in HIV-positive patients with CD4 < or = 200 cells/microL (45%) than in HIV-positive patients with CD4 > 200 cells/microL (17%) (P = .04). These differences, which were linked to HIV status, might be related to the enhanced HCV replication during HIV infection or other immune mechanisms that need further studies.

Adult↗

Impact of TT virus infection in acute and chronic, viral- and non viral-related liver diseases.

BACKGROUND/AIMS: The prevalence and pathogenicity of TT virus, recently identified in patients with non A-non G post-transfusional hepatitis, are questioned. METHODS: We investigated the impact of this new viral infection in a large series of patients with non A-non G, cryptogenic, non-viral and viral-related, acute and chronic liver diseases (n=577) and blood donors (n=300). TTV DNA was detected in serum by hemi-nested polymerase chain reaction. Phylogenetic analysis was performed in 13 isolates. RESULTS: TTV DNA was detected in 6/25 and 15/127 patients with cryptogenic non A-non G acute and chronic liver disease, respectively. TTV DNA positive subjects with post-transfusional acute hepatitis scored negative before transfusion. TTV prevalence was increased in patients with cryptogenic non A-non G acute and chronic liver disease compared to blood donors (6/300; p<0.001) and non-viral-related chronic liver diseases (6/137; p<0.05). TTV/HBV coinfection was frequently identified (35/147), but this was not the case for HCV-infected subjects (4/77). Transaminase activity or liver histological score was not significantly increased among TTV positive, HBV infected or non A-non G patients. The HBV infection and Mediterranean origin were the risk factors associated with TTV infection. The majority of analysed sequences clustered in genotype 1 (8=1b; 3=1a). Two isolates showed homology to genotype 2. CONCLUSIONS: These results support the view that TTV is a widely spread infectious agent with a weak pathogenicity. It raises the possibility, however, that TTV might be implicated in a few cases of acute and chronic non A-non G hepatitis. TTV-DNA-analysed sequences are related to genotypes 1 and 2 described in Europe.

Acute Disease↗