Viral Ribonucleic Acid Research Articles

Serum fibrosis markers (Procollagen-III-peptide, hyaluronic acid, transforming growth factor β-1), aspartate-aminotransferase to platelet ratio index (APRI), and transient elastography (FibroScan) in patients with chronic HCV infection

Background: Although liver biopsy (LB) is the gold standard for the morphological diagnosis of diseases of the liver, recent noninvasive tests may also help in the evaluation of liver fibrosis. We have studied blood fibrosis markers and liver stiffness (LS) measurement to assess fibrosis in different forms of chronic hepatitis C virus (HCV) infection. Patients and methods: Out of 119 HCV-infected patients, 75 had biopsy-proven chronic hepatitis C, 24 had HCV cirrhosis, 20 individuals were symptom-free HCV carriers with persistently normal alanine aminotransferase (PNA), and 30 healthy blood donors served as controls. Wai's aspartate-aminotransferase (AST) to platelet ratio index (APRI) was calculated from serum AST and blood platelet number. Serum HCV-RNA (hepatitis C virus ribonucleic acid), procollagen-III-peptide (P-III-P) and hyaluronic acid (HA), plasma transforming growth factor β-1 (TGFβ-1), Knodell's histological activity index (HAI), and METAVIR fibrosis score were determined, and for LS measurement transient elastography (TE) (FibroScan) was applied. Results: In chronic hepatitis C patients, all fibrosis markers were significantly elevated compared to normal controls. HA, APRI, and LS values were highest in HCV cirrhosis and nonresponders to PEG-IFN + ribavirin (P/R) therapy. High P-III-P values occurred only in advanced fibrosis. Serum HA correlated with the fibrosis stage. Plasma TGFβ-1 was significantly higher in patients with chronic hepatitis C than in symptom-free HCV carriers, and it correlated with HAI. After 3–6 months of P/R therapy, both HA and TGFβ-1 levels significantly decreased even in virological nonresponders. APRI was 0.21 ± 0.05 in normal controls, 0.20 ± 0.08 in symptom-free HCV carriers, 0.70 ± 0.40 in patients with chronic hepatitis C, and 3.21 ± 2.3 in HCV cirrhosis cases. LS values were 5.10 ± 1.19 kPa in controls, 5.38 ± 1.37 kPa in HCV carriers with PNA, 9.67 ± 4.11 kPa in chronic hepatitis C patients, 6.56 ± 2.61 kPa in patients with sustained virological response, 18.55 ± 11.65 kPa in nonresponders to P/R, and 37.40 ± 16.85 kPa in HCV cirrhosis cases. On the basis of a novel sequential algorithm that comprises APRI and LS for assessment of fibrosis, 47% of our HCV patients did not need biopsy for diagnosing significant (F ≥ 2) fibrosis. Conclusion: Both blood fibrosis markers and LS, particularly in combination, represent an advance in the noninvasive assessment of fibrosis in HCV infection. P/R treatment may inhibit fibrosis progression even independently of virological response.

Infectious Diseases Associated with Caves

In recent times, caving has become increasingly popular, with almost 2 million people visiting national park caves each year in the United States. Although the 2 million tourist visits are extremely low risk, smaller numbers of sport cavers are at risk for some high risk conditions, and expedition cavers are at risk for some obscure infections. Infectious diseases like histoplasmosis, rabies, leptospirosis, and tick-borne relapsing fever may be transmitted by the underground fauna. To reduce the risk of illness or injury while caving, knowledge of potential risks before engaging in this activity is important. Caving preparation needs to be carefully planned and executed, including vaccinations, prophylactic medications, and advice regarding safe conduct and behaviors.

HIV-1 remodels the nuclear pore complex

Human immunodeficiency virus type 1 (HIV-1) commandeers host cell proteins and machineries for its replication. Our earlier work showed that HIV-1 induced the cytoplasmic retention of nucleocytoplasmic shuttling and ribonucleic acid (RNA)-binding proteins. This retention is dependent on nuclear export of the viral genomic RNA and on changes in the localization and expression level of the nucleoporin (Nup) p62 (Nup62). To further characterize the extent of perturbation induced by HIV-1, we performed proteomics analyses of nuclear envelopes (NEs) isolated from infected T cells. Infection induced extensive changes in the composition of the NE and its associated proteins, including a remarkable decrease in the abundance of Nups. Immunogold electron microscopy revealed the translocation of Nups into the cytoplasm. Nup62 was identified as a component of purified virus, and small interfering RNA depletion studies revealed an important role for this Nup in virus gene expression and infectivity. This detailed analysis highlights the profound effects on NE composition induced by HIV-1 infection, providing further evidence of the magnitude of viral control over the cell biology of its host.

Laboratory Surveillance of Rabies in Humans, Domestic Animals, and Bats in Madagascar from 2005 to 2010

Background. Rabies virus (RABV) has circulated in Madagascar at least since the 19th century. Objectives. To assess the circulation of lyssavirus in the island from 2005 to 2010. Materials and Methods. Animal (including bats) and human samples were tested for RABV and other lyssavirus using antigen, ribonucleic acid (RNA), and antibodies detection and virus isolation. Results. Half of the 437 domestic or tame wild terrestrial mammal brains tested were found RABV antigen positive, including 54% of the 341 dogs tested. This percentage ranged from 26% to 75% across the period. Nine of the 10 suspected human cases tested were laboratory confirmed. RABV circulation was confirmed in 34 of the 38 districts sampled. No lyssavirus RNA was detected in 1983 bats specimens. Nevertheless, antibodies against Lagos bat virus were detected in the sera of 12 among 50 Eidolon dupreanum specimens sampled. Conclusion. More than a century after the introduction of the vaccine, rabies still remains endemic in Madagascar.

The accuracy of Influenza A (H1N1) “swine flu” laboratory testing: A systematic review of diagnostic test accuracy.

The accuracy of Influenza A (H1N1) “swine flu” laboratory testing: A systematic review of diagnostic test accuracy.

Dengue hemorrhagic fever and shock syndromes*

To provide a comprehensive review of dengue, with an emphasis on clinical syndromes, classification, diagnosis, and management, and to outline relevant aspects of epidemiology, immunopathogenesis, and prevention strategies. Dengue, a leading cause of childhood mortality in Asia and South America, is the most rapidly spreading and important arboviral disease in the world and has a geographic distribution of > 100 countries. Boolean searches were carried out by using PubMed from 1975 to March 2009 and the Cochrane Database of Systematic Reviews from 1993 to March 2009 to identify potentially relevant articles by key search terms such as: "dengue"; "dengue fever"; "dengue hemorrhagic fever"; "dengue shock syndrome"; "severe dengue" and "immunopathogenesis," pathogenesis," "classification," "complications," and "management." In addition, authoritative seminal and up-to-date reviews by experts were used. Original research and up-to-date reviews and authoritative reviews consensus statements relevant to diagnosis and therapy were selected. We considered the most relevant articles that would be important and of interest to the critical care practitioner as well as authoritative consensus statements from the World Health Organization and the Centers for Disease Control and Prevention. Dengue viral infections are caused by one of four single-stranded ribonucleic acid viruses of the family Flaviviridae and are transmitted by their mosquito vector, Aedes aegypti. The clinical syndromes caused by dengue viral infections occur along a continuum; most cases are asymptomatic and few present with severe forms characterized by shock. Management is predominantly supportive and includes methods to judiciously resolve shock and control bleeding while at the same time preventing fluid overload. Dengue is no longer confined to the tropics and is a global disease. Treatment is supportive. Outcomes can be optimized by early recognition and cautious titrated fluid replacement, especially in resource-limited environments.

Joint modeling of longitudinal data and informative dropout time in the presence of multiple changepoints

In longitudinal studies of patients with the human immunodeficiency virus (HIV), objectives of interest often include modeling of individual-level trajectories of HIV ribonucleic acid (RNA) as a function of time. Such models can be used to predict the effects of different treatment regimens or to classify subjects into subgroups with similar trajectories. Empirical evidence, however, suggests that individual trajectories often possess multiple points of rapid change, which may vary from subject to subject. Additionally, some individuals may end up dropping out of the study and the tendency to drop out may be related to the level of the biomarker. Modeling of individual viral RNA profiles is challenging in the presence of these changes, and currently available methods do not address all the issues such as multiple changes, informative dropout, clustering, etc. in a single model. In this article, we propose a new joint model, where a multiple-changepoint model is proposed for the longitudinal viral RNA response and a proportional hazards model for the time of dropout process. Dirichlet process (DP) priors are used to model the distribution of the individual random effects and error distribution. In addition to robustifying the model against possible misspecifications, the DP leads to a natural clustering of subjects with similar trajectories which can be of importance in itself. Sharing of information among subjects with similar trajectories also results in improved parameter estimation. A fully Bayesian approach for model fitting and prediction is implemented using MCMC procedures on the ACTG 398 clinical trial data. The proposed model is seen to give rise to improved estimates of individual trajectories when compared with a parametric approach.

Hepatitis A and Hepatitis C Viruses: Divergent Infection Outcomes Marked by Similarities in Induction and Evasion of Interferon Responses

Hepatitis A and hepatitis C viruses (HAV and HCV) are both positive-strand ribonucleic acid (RNA) viruses with hepatotropic lifestyles. Despite several important differences, they share many biological and molecular features and similar genome replication schemes. Despite this, HAV infections are usually effectively controlled by the host with elimination of the virus, whereas HCV most often is able to establish lifelong persistent infection. The mechanisms underlying this difference are unknown. The cellular helicases RIG-I and MDA5, and Toll-like receptor 3, are pattern recognition receptors that sense virus-derived RNAs within hepatocytes in the liver. Activation of these receptors leads to their interaction with specific adaptor proteins, mitochondrial antiviral signaling protein (MAVS) and TIR-domain-containing adapter-inducing interferon-β (TRIF), respectively, which engage downstream kinases to activate two crucial transcription factors, nuclear factor kappa B (NF-κB) and interferon regulatory factor 3 (IRF3). This results in the induction of interferons (IFNs) and IFN-stimulated genes that ultimately establish an antiviral state. These signaling pathways are central to host antiviral defense and thus frequent targets for viral interference. Both HAV and HCV express proteases that target signal transduction through these pathways and that block the induction of IFNs upon sensing of viral RNA by these receptors. An understanding of the differences and similarities in the early innate immune responses to these infections is likely to provide important insights into the mechanism underlying the long-term persistence of HCV.

SARNA-Predict: Accuracy Improvement of RNA Secondary Structure Prediction Using Permutation-Based Simulated Annealing

Ribonucleic acid (RNA), a single-stranded linear molecule, is essential to all biological systems. Different regions of the same RNA strand will fold together via base pair interactions to make intricate secondary and tertiary structures that guide crucial homeostatic processes in living organisms. Since the structure of RNA molecules is the key to their function, algorithms for the prediction of RNA structure are of great value. In this article, we demonstrate the usefulness of SARNA-Predict, an RNA secondary structure prediction algorithm based on Simulated Annealing (SA). A performance evaluation of SARNA-Predict in terms of prediction accuracy is made via comparison with eight state-of-the-art RNA prediction algorithms: mfold, Pseudoknot (pknotsRE), NUPACK, pknotsRG-mfe, Sfold, HotKnots, ILM, and STAR. These algorithms are from three different classes: heuristic, dynamic programming, and statistical sampling techniques. An evaluation for the performance of SARNA-Predict in terms of prediction accuracy was verified with native structures. Experiments on 33 individual known structures from eleven RNA classes (tRNA, viral RNA, antigenomic HDV, telomerase RNA, tmRNA, rRNA, RNaseP, 5S rRNA, Group I intron 23S rRNA, Group I intron 16S rRNA, and 16S rRNA) were performed. The results presented in this paper demonstrate that SARNA-Predict can out-perform other state-of-the-art algorithms in terms of prediction accuracy. Furthermore, there is substantial improvement of prediction accuracy by incorporating a more sophisticated thermodynamic model (efn2).

Clinical characteristics of hepatitis E in a “Non‐Endemic” population

Hepatitis E virus (HEV) is a ribonucleic acid (RNA) virus with predominant fecal oral spread. Traditionally in Western Europe it is associated with travel to endemic countries, but an increasing number of locally acquired cases have been reported throughout England. Patients presenting with acute non-travel associated HEV infection in south Wales over a 25-month period were monitored, in an attempt to understand the clinical picture and epidemiology in our patient population. Twenty-four patients were identified with non-travel associated HEV infection and studied prospectively. Patient demographics, symptoms, and serial laboratory results were recorded. There was a male/female ratio of 3:1, with a median patient age of 65.5 years old. Patients developed a significant icteric hepatitis (median peak bilirubin: 139 µmol/L, median peak AST: 1,973 IU/L and ALT: 2,021 IU/L), with liver function remaining abnormal for ∼7 weeks. All patients in whom HEV RNA was isolated were infected with genotype 3. Forty-six percent of patients presented during winter months. The data show a group mortality rate of 4.2%, similar to that reported in endemic countries. HEV results in a severe and occasionally fatal hepatitis. Testing for hepatitis E is now recommended in any patient presenting with acute hepatitis of unknown etiology.

Incidence of hepatitis E virus infection in recipients of blood or blood products transfusion

Background: Hepatitis E, generally known to be transmitted faeco-orally, has been shown to have significant transmission by blood borne route. Paucity of data on asymptomatic viremia in blood donors and higher incidence of Hepatitis E in haemodialysis patients and thalassemics mandate a prospective study of blood recipients to elucidate the exact incidence and natural history of post transfusion Hepatitis E. Methods: A total of 2000 recipients of blood or blood products transfusion were followed up for two months to detect development of post transfusion Hepatitis E, by clinical examination, transaminases and immunoglobulin M anti hepatitis E virus (IgM anti HEV). Estimation of hepatitis E virus ribonucleic acid (HEV RNA) was done in patients with elevated levels of transaminases. Result: Out of 2000 patients, 5(0.25%) were positive for IgM anti HEV at the time of transfusion and were excluded from the study. Rest of 1995 patients were followed up for two months post transfusion. A total of 1303 (65.3%) patients were followed up for two months and 1636 (82.0%) patients at least once in two visits. None of the followed up patients reported development of jaundice or had clinically evident hepatitis, although 62 patients had raised transaminases detected at either one or both the visits. Conclusion: All followed up patients were tested for IgM anti HEV at both the visits and none were found to be positive. Patients with raised transaminases were subjected to HEV RNA and all were found to be negative.

Abnormal macrophage response to microbial stimulus in a 43-year-old man with a severe form of atherosclerosis: a case report

IntroductionNew evidence indicates infections are emerging as risk factors for atherosclerosis although their specific role in the development and progression of atherosclerosis is still unclear.Case presentationA 43-year-old Caucasian man who had been treated for four years for multiple sclerosis progressively manifested systemic hypertension, polycythemia, peripheral arterial occlusion with intermittent claudication, and persistent headaches. In 2006, an instrumental analysis (magnetic resonance imaging) of our patient revealed widespread fibrocalcific atherosclerotic lesions which accounted for all his current symptoms, including those related to microbial stimulus. Two particular aspects were of interest, namely a lack of conventional cardiovascular risk factors and a negative family history for cardiovascular events. His chemical blood tests all yielded negative findings although a low positive hepatitis C virus-ribonucleic acid titer was detected. The titer had progressively increased and worsening atherosclerosis threatened the life of our patient. Interferon therapy was not appropriate for our patient due to the severe adverse effects observed shortly after its administration.ConclusionsThe reaction of individual cells to infections may provide an explanation as to why individuals with a similar microbial burden, corrected for the presence of other risk factors, display a different susceptibility to developing or worsening atherosclerosis. The identification of susceptible individuals and the treatment even of silent infections may provide an additional tool against atherosclerosis and its clinical complications. The evaluation of cell susceptibility before and after the correction of risk factors may contribute to the assessment of the efficacy of drug therapy.

Interferon Alpha-Induced Hashimoto Thyroiditis Followed by Transient Graves Disease in a Patient with Chronic HCV Infection

The case of a 37-year-old man with chronic hepatitis C virus (HCV) infection is presented. The patient had received a 6-month course of antiviral therapy with peg interferon alpha-2a and ribavirin, with concomitant clearance of hepatitis C virus ribonucleic acid (HCV-RNA) from serum at the end of treatment. Three months after the treatment course he developed clinical and laboratory features of hypothyroidism along with high titers of thyroid peroxidase antibodies. Later on, while on treatment with levothyroxine, he developed all the clinical features of Graves disease along with increased levels of thyroid stimulating hormone (TSH)-receptor antibodies.This patient exhibited a rare sequence of immune-mediated thyroid disorders as a result of interferon alpha treatment. At the end of treatment, the patient developed Hashimoto thyroiditis, a typically Th1-response-mediated disease, followed sequentially after 6 months by Graves disease, a typically Th2-response-mediated disorder. Although both clinical entities have been described in patients receiving interferon-based regimens, to our knowledge, the changing pattern of immune-mediated thyroid disease in the same individual has not been reported in the literature.

Predictors of Treatment Failure in Cambodian Children With Human Immunodeficiency Virus Infection

To the Editors: Jittamala et al1 in their article in the September issue of Pediatric Infectious Disease Journal on predictors of treatment failure documented that nevirapin but not human immunodeficiency virus-ribonucleic acid titer was predictive for virologic failure in a cohort of Thai children after 4.5 years of follow-up. We analyzed 102 children aged 4 to 16 years who were infected by human immunodeficiency virus in our orphanages in Phnom Penh, Cambodia, in 2003–2009 on genotypic resistance as a cause of first-line failure and for adherence to HAART, virologic, clinical, and immunologic response to HAART. Of 102 children, only 7 failed after 18 to 36 months on first-line treatment stavudine (d4T), lamivudine (3TC) plus nevirapine. Clinical checkup has been done daily by physicians. CD4 cells were investigated every 3 months and viral load 6 monthly. Genotypic/phenotypic resistance tests were performed after December 2004 in case of clinical or immunologic failure by National Pediatric Hospital laboratory affiliated to Institute Pasteur Cambodge, Phnom Penh. Mortality on acquired immunodeficiency syndrome and acquired immunodeficiency syndrome-related opportunistic infections in our group of 102 children was <3%, and only 3 children died in 2003–2009. Two children died even before the onset of therapy (late arrival to clinic), 1 at the beginning of HAART (first month). All had CD4 counts <10 cells/mL (<5%) at admission. The rest of the 98 children were treated with HAART from 18 to 72 months: 7 of 99 (7%) failed between 15 and 36 months. As a failure, we considered when CD4 count decreased (2 measurements within 6 months) and viral load showed increasing tendency (>1000 copies/mL). Only viral load increase (without immunologic correlate in 1 child) or only CD4 decrease (discordant failure in 2 children) was not considered as indicator for replacement of the first-line. Most of the children failed on D4T + 3TC + nevirapine, which was replaced by abacavir (ABC), didanosine (DDI), zidovudine (ZDV), or tenofovir (TDF) with protease inhibitors—lopinavir/ritonavir or efavirenz (available after 2007). Commonest mutations of the reverse transcription (responsible for both genotypic and phenotypic resistance) among nucleoside analog reverse transcriptase inhibitors (NRTIs) were M184V (5 children), V75M (3 children), and T215Y and among non-NRTIs (NNRTIs), commonest mutations were K103N (2 children) and K101E (2 children). Those who failed on first-line were treated by TDF, ABC or DDI, and ZDV. DDI was still left in the NRTI backbone with TDF or ZDV, or ABC plus protease inhibitors was added. All 7 children who were treated with second-line showed rapid decline of viral load (from 5.4 to <2.4 log) and increase of CD4 percentage (used in children and young adults indication response—virologic and immunologic). There are no studies on efficacy and pharmacokinetics of new form fusion, entry, and C-C chemokine receptor type 5 (CCR5) antagonist-class antiretrovirals in children. Therefore, optimal dosing especially in children with body weight <15 kg is unknown. Cambodia, in contrast to Europe and the United States, has few therapeutic options for pediatric HAART in developing countries. Only lopinavir/ritonavir and nelfinavir produced by Thai and Indian pharmaceutical industries were available in 2003–2007. In contrast to the results published by Jittamala et al1 reporting failure in 40 of 202 children (20%), failure rate in own count of 102 children within 6 years was 7%. Of 4 children who died, 3 had not received any treatment and 1 died after 1 month; all 4 came very late to assess the effect of potential therapy because they arrived in terminal stage (<10 CD4 cells). We have no explanation for low number of deaths (3%) and virologic/immunologic failures (7%) among our group of children in Cambodia within 6 years of follow-up. Probably, high proportion of those receiving efavirenz (90%) versus nevirapin (8%) because of concomitant anti-TB therapy for tuberculosis may explain our 7% failure rate (after 6 years of follow-up). Efavirenz and adherence were protective against failure in the Thai study1 and a review in several studies on pediatric ART.2 All our children were placed in 2 orphanages with good nutrition (5 × daily) on inpatient basis, with up to 100% adherence, which may also contribute to low failure rate. Irad Beldjebel, MD St. Maximilian Kolbe Tropical Clinic of Infectious Diseases, SEUC Sangkat Buoeung Tumpong, Khan Meanchey Phnom Penh, Kingdom of Cambodia Julia Vujcikova, MD Tropical Programs SEUC Sihanoukville, Kingdom of Cambodia Jaroslava Sokolova, MSc Department of Clinical Disciplines School of Health Care and Social Work Trnava University Trnava, Slovak Republic St. Elizabeth University College of Health and Social Sciences Bratislava, Slovak Republic Vladimir Krcmery, MD, DSc St. Elizabeth University College of Health and Social Sciences Bratislava, Slovak Republic

Virological and pathological findings in Bluetongue virus serotype 8 infected sheep

Twenty-seven sheep of the four most common Swiss breeds and the English breed Poll Dorset were experimentally infected with a northern European field strain of bluetongue virus serotype 8 (BTV-8). Animals of all breeds developed clinical signs, viremia and pathological lesions, demonstrating that BTV-8 is fully capable of replicating and inducing bluetongue disease (BT) in the investigated sheep. Necropsy performed between 10 and 16 days post-infectionem (d.p.i.) revealed BT-typical hemorrhages, effusions, edema, erosions and activation of lymphatic tissues. Hemorrhages on the base of the Arteria pulmonalis and the left Musculus papillaris subauricularis were frequently present. Histology confirmed the macroscopical findings. Using a score system, clinical manifestation and pathology were found to be significantly related. Furthermore, clinical signs and fever were shown to be indicative for the concurrent presence of high amounts of viral ribonucleic acid (RNA) in blood. Spleen, lung, lymph nodes and tonsils from all animals were analyzed regarding viral RNA loads and infectivity using real-time reverse transcriptase PCR (rRT-PCR) and virus isolation in cell culture, respectively. The highest amount of viral RNA was detected in spleen and lung and rRT-PCR revealed to be a more sensitive method for virus detection compared to virus isolation. A long-term follow-up was performed with three sheep showing that BTV-8 viral RNA in blood was present up to 133 d.p.i. and in certain tissues even on 151 d.p.i. No significant breed-related differences were observed concerning clinicopathological picture and viremia, and the Swiss sheep were as susceptible to BTV-8 infection as Poll Dorset sheep, demonstrating a remarkably high virulence of BTV-8 for indigenous sheep breeds.

Clinical implications of hepatitis A virus ribonucleic acid detection and genotyping in acute liver failure in children in Argentina

To investigate the detection of hepatitis A virus ribonucleic acid in patients with acute liver failure and to assess if the results have any clinical implications for the evolution of acute liver failure in children. Hepatitis A infection, a vaccine-preventable disease, is an important cause of acute liver failure in children in Argentina. Universal vaccination in 1-yr-old children was implemented in June 2005. Observational study in which patients were divided into Group 1 consisting of positive hepatitis A virus ribonucleic acid and Group 2 consisting of negative hepatitis A virus ribonucleic acid. Pediatric intensive care unit in National Pediatric Hospital "Dr. J. P. Garrahan," Buenos Aires, Argentina. Thirty-three patients with the diagnosis of acute liver failure secondary to hepatitis A virus infection and admitted to the Garrahan Pediatric Hospital between September 2003 and September 2005 were enrolled in the study. Twenty of these children were admitted to the pediatric intensive care unit. None. Samples for total ribonucleic acid detection and genotyping were obtained from serum and/or stools on admission. We found positive hepatitis A virus ribonucleic acid in 13 patients and negative hepatitis A virus ribonucleic acid in 20 patients. The following clinical variables were evaluated: time of evolution, hospital stay, admission to the pediatric intensive care unit, pediatric intensive care unit stay, time on mechanical ventilation, criteria for orthotopic liver transplantation, and mortality. Characterization of the isolates did not reveal differences related to genotype; all cases were IA. No statistical significance was found as to the variables. However, positive hepatitis A virus ribonucleic acid showed lower percentages of pediatric intensive care unit admissions, criteria for orthotopic liver transplantation, number of orthotopic liver transplantation, and mortality than the group of patients with negative hepatitis A virus ribonucleic acid. Hepatitis A virus genotyping studies did not show any particularities, all cases were IA and, thus, apparent associations between genotype and the clinical presentation of acute liver failure could not be found.

Correlation of hepatitis C RNA and serum alanine aminotransferase in hepatitis B and C seronegative healthy blood donors

Historically, serum alanine transaminase (ALT) has been used as a surrogate marker in the detection of hepatitis viruses in blood donors. With the availability of newer sensitive technologies for the detection of seroconversion, the value of ALT becomes questionable but continues to be used for this purpose with subsequent discarding of ALT elevated blood units. The present study aims to evaluate the significance and cost effectiveness of ALT as a surrogate marker for hepatitis C virus infection in healthy asymptomatic blood donors who were serologically negative. The study was conducted at clinical laboratory of a tertiary care hospital for a period of one year from November 2006 to October 2007. All donors were screened serologically for hepatitis B, C and HIV I and II, syphilis and malaria and those tested positive were excluded from further evaluation. Gender-wise reference ranges and minimal and markedly raised results for ALT (described respectively as one and two folds increase above reference range) were defined and, accordingly, donors were grouped into three. Two hundred seronegative blood donors were randomly selected from all three groups of ALT results and tested for hepatitis C nucleic acid through Amplicor HCV RNA test. The cost of discarding an ALT -only elevated blood unit was also assessed. During the study period, 25117 subjects donated blood. EIGHT HUNDRED AND RESULTS: Seventy two donors (3.4%) were positive for one or more serological tests. ALT of all donors ranged from 0-1501 U/L (Mean +/- SD; 33.4 +/- 25.45 U/L). The donors seronegative for all disease markers were 24245 (96.6%). Of these, 21164 (87.2%) donors had their ALT within reference range while 2874 (11.8%) and 207 (0.8%) of donors had minimal and markedly elevated results. Thus, 621 blood bags (red cells, platelets and plasma) costing $ 39200.0 were discarded based on ALT results alone. Of 200 seronegative donors evaluated for hepatitis C nucleic acid, only one within markedly elevated ALT levels was found to be positive. The present work did not support a positive association between hepatitis C virus nucleic acid and elevated ALT in healthy serologically negative blood donors. We did not find serum ALT testing in donors as cost effective strategy for detection of hepatitis C virus ribonucleic acid. As the number of samples tested by us was small we suggest further work to evaluate the value of ALT levels in serologically negative donors in association with hepatitis C antigen and NAT testing to elucidate the true burden of disease in geographical regions where hepatitis C is endemic and voluntary blood donation is sparse.

The accuracy of Influenza A (H1N1) “swine flu” laboratory testing: A systematic review of diagnostic test accuracy.

The accuracy of Influenza A (H1N1) “swine flu” laboratory testing: A systematic review of diagnostic test accuracy.

Mitochondrial dynamics regulate the RIG‐I‐like receptor antiviral pathway

The intracellular retinoic acid-inducible gene I-like receptors (RLRs) sense viral ribonucleic acid and signal through the mitochondrial protein mitochondrial antiviral signalling (MAVS) to trigger the production of type I interferons and proinflammatory cytokines. In this study, we report that RLR activation promotes elongation of the mitochondrial network. Mimicking this elongation enhances signalling downstream from MAVS and favours the binding of MAVS to stimulator of interferon genes, an endoplasmic reticulum (ER) protein involved in the RLR pathway. By contrast, enforced mitochondrial fragmentation dampens signalling and reduces the association between both proteins. Our finding that MAVS is associated with a pool of mitofusin 1, a protein of the mitochondrial fusion machinery, suggests that MAVS is capable of regulating mitochondrial dynamics to facilitate the mitochondria-ER association required for signal transduction. Importantly, we observed that viral mitochondria-localized inhibitor of apoptosis, a cytomegalovirus (CMV) antiapoptotic protein that promotes mitochondrial fragmentation, inhibits signalling downstream from MAVS, suggesting a possible new immune modulation strategy of the CMV.

Determination of HCV Genotypes among Chronic Hepatic Patients in Ahvaz

Background and Aims: Chronic hepatitis C is one of the most important etiologies of cirrhosis and hepatocellular carcinoma worldwide. Clinical condition of hepatic patients and the outcome of chemotherapy are under impact of Hepatitis C virus (HCV) genotypes. Therefore, HCV genotyping is important for prediction of success of chemotherapy and progression of liver diseases. Methods: In this article the distribution of HCV genotypes detected in a population in Ahvaz, southwest of Iran is reported. This was a study on 80 patients suffering from chronic hepatitis C. Following extraction of the viral ribonucleic acid (RNA) patient’s sera, from it was used as the template for the synthesis of complementary deoxyribonucleic acid (cDNA). The amplified fragments of HCV cDNAs by nested PCR were subjected to restriction enzyme analysis. Restriction Fragment Length Polymorphism (RLFP) was performed on all HCV isolates to determine the subgenotype. Results: Out of 80 HCV positive samples 43 (53.8%) were genotype 1a and 37 (46.2%) were genotype 3a. The dominant genotype of HCV isolated from patients suffering from chronic hepatitis C in Ahvaz was genotype 1a. Therefore, interferon therapy may not help some of these patients against HCV infection. Conclusion: It is suggested to perform HCV genotyping prior to interferon therapy. Besides, the result suggests that the major route of HCV infection in Ahvaz population is the use of contaminated syringe.