49 research outputs found

    Development of a new ultra sensitive real-time PCR assay (ultra sensitive RTQ-PCR) for the quantification of HBV-DNA

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    <p>Abstract</p> <p>Background</p> <p>Improved sensitivity of HBV-DNA tests is of critical importance for the management of HBV infection. Our aim was to develop and assess a new ultra sensitive in-house real-time PCR assay for HBV-DNA quantification (ultra sensitive RTQ-PCR).</p> <p>Results</p> <p>Previously used HBV-DNA standards were calibrated against the WHO 1<sup>st </sup>International Standard for HBV-DNA (OptiQuant<sup>® </sup>HBV-DNA Quantification Panel, Accrometrix Europe B.V.). The 95% and 50% HBV-DNA detection end-point of the assay were 22.2 and 8.4 IU/mL. According to the calibration results, 1 IU/mL equals 2.8 copies/mL. Importantly the clinical performance of the ultra sensitive real-time PCR was tested similar (67%) to the Procleix Ultrio discriminatory HBV test (dHBV) (70%) in low-titer samples from patients with occult Hepatitis B. Finally, in the comparison of ultra sensitive RTQ-PCR with the commercially available COBAS TaqMan HBV Test, the in-house assay identified 94.7% of the 94 specimens as positive versus 90.4% identified by TaqMan, while the quantitative results that were positive by both assay were strongly correlated (<it>r </it>= 0.979).</p> <p>Conclusions</p> <p>We report a new ultra sensitive real time PCR molecular beacon based assay with remarkable analytical and clinical sensitivity, calibrated against the WHO 1<sup>st </sup>International standard.</p

    HCV Defective Genomes Promote Persistent Infection by Modulating the Viral Life Cycle

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    Defective interfering (DI) RNAs have been detected in several human viruses. HCV in-frame deletions mutants (IFDMs), missing mainly the envelope proteins, have been found in patient sera and liver tissues. IFDMs replicate independently and can be trans-packaged into infectious virions in the presence of full length viral genome. So far, their biological role is unclear. In this study, we have isolated and cloned IFDMs from sera samples and liver tissues of patients infected with HCV genotypes 1b, 2a, and 3a. IFDMs were present in up to 26% of samples tested. Using the in vitro HCV cell culture system, co-expression of the wild type (wt) HCV replicon with HCV IFDMs RNA resulted in increased HCV replication. Additionally, co-transfection of the HCV full length genome RNA and a defective mutant missing the envelope region led to increased viral release, collectively suggesting an important biological role for IFDMs in the virus life cycle. Recently, exosomes, masters of intercellular communication, have been implicated in the transport of HCV viral genomes. We report for the first time that exosomal RNA isolated from HCV sera samples contains HCV defective genomes. We also demonstrate that inhibition of exosomal biogenesis and release influences HCV viral replication. Overall, we provide evidence that the presence of HCV IFDMs affects both viral replication and release. IFDMs exploit exosomes as means of transport, a way to evade the immune system, to spread more efficiently and possibly maintain persistent infection

    Analysis of natural variants of the hepatitis C virus internal ribosome entry site reveals that primary sequence plays a key role in cap-independent translation

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    The HCV internal ribosome entry site (IRES) spans a region of ∼340 nt that encompasses most of the 5′ untranslated region (5′UTR) of the viral mRNA and the first 24–40 nt of the core-coding region. To investigate the implication of altering the primary sequence of the 5′UTR on IRES activity, naturally occurring variants of the 5′UTR were isolated from clinical samples and analyzed. The impact of the identified mutations on translation was evaluated in the context of RLuc/FLuc bicistronic RNAs. Results show that depending on their location within the RNA structure, these naturally occurring mutations cause a range of effects on IRES activity. However, mutations within subdomain IIId hinder HCV IRES-mediated translation. In an attempt to explain these data, the dynamic behavior of the subdomain IIId was analyzed by means of molecular dynamics (MD) simulations. Despite the loss of function, MD simulations predicted that mutant G266A/G268U possesses a structure similar to the wt-RNA. This prediction was validated by analyzing the secondary structure of the isolated IIId RNAs by circular dichroism spectroscopy in the presence or absence of Mg2+ ions. These data strongly suggest that the primary sequence of subdomain IIId plays a key role in HCV IRES-mediated translation

    Redox regulation of hepatitis C in nonalcoholic and alcoholic liver

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    Hepatitis C virus (HCV) is an RNA virus of the Flaviviridae family that is estimated to have infected 170 million people worldwide. HCV can cause serious liver disease in humans, such as cirrhosis, steatosis, and hepatocellular carcinoma. HCV induces a state of oxidative/nitrosative stress in patients through multiple mechanisms, and this redox perturbation has been recognized as a key player in HCV-induced pathogenesis. Studies have shown that alcohol synergizes with HCV in the pathogenesis of liver disease, and part of these effects may be mediated by reactive species that are generated during hepatic metabolism of alcohol. Furthenriore, reactive species and alcohol may influence HCV replication and the outcome of interferon therapy. Alcohol consumption has also been associated with increased sequence heterogeneity of the HCV RNA sequences, suggesting multiple modes of interaction between alcohol and HCV. This review summarizes the current understanding of oxidative and nitrosative stress during HCV infection and possible combined effects of HCV, alcohol, and reactive species in the pathogenesis of liver disease. (c) 2007 Elsevier Inc. All rights reserved

    Psychometric Properties of the Greek Haem-A-QoL for Measuring Quality of Life in Greek Haemophilia Patients

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    Background and Objectives. Health Related Quality of Life (HRQoL) is an important health outcome measure in haemophilia. The aim of this study was to assess the psychometric properties of the Greek version of Haem-A-QoL, a disease-specific questionnaire for haemophiliacs. Methods. Haem-A-QoL and SF-36 were administered to 118 adult haemophilia patients. Hypothesized scale structure, internal consistency (Cronbach’s α), and test-retest reliability, as well as various types of construct validity were evaluated. Results. Scale structure of Haem-A-QoL was confirmed, with good item convergence (87%) and discrimination (80.6%) rates. Cronbach’s α was >0.70 for all but one dimension (dealing) and test-retest reliability was significantly high. The strength of Spearman’s correlations between Haem-A-QoL and SF-36 scales ranged from 0.25 to 0.75 (P<0.01). Multiple stepwise linear regression analysis revealed that all but one Haem-A-QoL dimensions were important predictors of SF-36 scales. Known-groups comparisons yielded consistent support of the instruments’ construct validity and significant relationships were identified for age, educational level, haemophilia type, disease severity, and viral infections. Conclusion. Overall, the psychometric properties of the Greek version of Haem-A-QoL, resulting from this first time administration of the instrument to Greek adult haemophiliacs, confirmed it as a reliable and valid questionnaire for assessing haemophilia-specific HRQoL in Greece

    Health-Related Quality of Life and Association With Arthropathy in Greek Patients with Hemophilia

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    Health-related quality of life (HRQoL) is increasingly implicated in contemporary hemophilia management. This study focuses on the assessment of HRQoL in Greek patients with hemophilia and the comparison with normative data from the general population, as well as on the extent arthropathy may affect the patients’ HRQoL. One hundred and nine adult patients completed the Greek social functioning (SF-36) and Haem-A-QoL questionnaires. Arthropathy was assessed by both the World Federation of Hemophilia clinical score and Pettersson radiological score. The most impaired domains of Haem-A-QoL were sports/leisure (SL) and physical health (PH; mean scores 61.2 and 42.2, respectively). The patients experienced statistically significant lower mean scores in all SF-36 domains than the normative sample, especially in role physical (RPH), bodily pain (BP), and general health (GH) subscales. Among Haem-A-QoL subscales, SL and PH were found strongly associated with severity of arthropathy using both orthopedic scores (P &lt;.001), and maintained the statistical significance after adjustment for age (P &lt;.05). A poor orthopedic status was also negatively associated with certain SF-36 subscales. However, none of these correlations remained after adjustment with age. Compared to normative data from Greece, patients with hemophilia showed deterioration in all HRQoL subscales, with a more pronounced effect in RPH, BP, and GH subscales. Health-related quality of life was strongly influenced by arthropathy, mainly in the physical aspects of HRQoL. The use of the disease-specific Haem-A-QoL tool can capture additional associations between HRQoL and hemophilic arthropathy. © 2017, © The Author(s) 2017

    Quality of life and patient compliance with medical treatment after heart transplantation

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    OBJECTIVE To evaluate the quality of life (QoL) and compliance with prescribed treatment of patients following heart transplantation. METHOD The study population consisted of 65 patients who underwent heart transplantation during the last 15 years. The SF-36 Health Status Questionnaire was administered to assess QoL and the Morisky Medication Adherence Scale (MMAS) to record adherence to the prescribed medication regime. The data were analyzed using the Statistical Package for Social Sciences (SPSS), version 19.0. RESULTS Of the 65 patients, 53 (81.5%) were men, and their mean age was 48.2±13.1 years. The total SF-36 scale score was 67±8. No significant differences were found between the scores on the 8 scales of the SF-36 questionnaire and the age, gender, family status, and educational level of the patients (all p>0.05). The majority of patients 66.1% (n=43) showed a high degree of compliance with the prescribed treatment. No correlation was found between the MMAS score and scores on any of the 8 SF-36 scales or the total SF-36 score. CONCLUSIONS Heart transplant patients reported a satisfactory QoL after surgery and a high level of compliance with medication treatment. The further exploration of the QoL of patients undergoing heart transplantation and the understanding of its association with demographic characteristics may contribute to improvement in the health care and better support of patients after heart transplantation
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