SciCombinator

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Concept: Hepatitis B

326

Patients with chronic hepatitis C virus (HCV) infection and cirrhosis have higher risk for liver-related complications and have historically been more difficult to cure than patients without cirrhosis. We evaluated the safety and efficacy of ombitasvir/paritaprevir/ritonavir and dasabuvir, without ribavirin, for 12 weeks in patients with HCV GT1b infection and compensated cirrhosis.

Concepts: Hepatitis A, Wilson's disease, Hepatitis C virus, Hepatocellular carcinoma, Hepatitis B, Cirrhosis, Hepatitis, Hepatitis C

175

Treatment with lamivudine of patients infected with hepatitis B virus (HBV) results in a high rate of drug resistance, which is primarily associated with the rtM204I/V substitution in the HBV reverse transcriptase domain. Here we show that the rtM204I/V substitution, although essential, is insufficient for establishing resistance against lamivudine. The analysis of 639 HBV whole-genome sequences obtained from 11 patients shows that rtM204I/V is independently acquired by more than one intra-host HBV variant, indicating the convergent nature of lamivudine resistance. The differential capacity of HBV variants to develop drug resistance suggests that fitness effects of drug-resistance mutations depend on the genetic structure of the HBV genome. An analysis of Bayesian networks that connect rtM204I/V to many sites of HBV proteins confirms that lamivudine resistance is a complex trait encoded by the entire HBV genome rather than by a single mutation. These findings have implications for public health and offer a more general framework for understanding drug resistance.

Concepts: Hepatitis B virus, Evolution, Gene, Genetic algorithm, Lamivudine, DNA, Genetics, Hepatitis B

172

The study was designed to characterize the surface, core promoter, precore/core region sequences for the presence of mutations in hepatitis B virus (HBV) associated with different liver diseases.

Concepts: Gene, Promoter, Hepatitis B virus, Cancer, DNA, Hepatitis, Cirrhosis, Hepatitis B

170

Micro RNAs-371-372-373 (miRNAs-371-373), originating from the same pri-miRNA transcript, are reported to be upregulated in hepatocellular carcinoma (HCC) and to be related to the regulation of hepatitis B virus (HBV) infection. Our study investigated whether pri-miRNAs-371-373 polymorphisms are associated with the risk of HCC occurrence and HBV clearance.

Concepts: Hepatitis C, Infection, Hepatitis B virus, RNA, DNA, Hepatitis, Cirrhosis, Hepatitis B

169

BACKGROUND: Hepatitis B virus (HBV), because of its error-prone viral polymerase, has a high mutation rate leading to widespread substitutions, deletions, and insertions in the HBV genome. Deletions may significantly change viral biological features complicating the progression of liver diseases. However, the clinical conditions correlating to the accumulation of deleted mutants remain unclear. In this study, we explored HBV deletion patterns and their association with disease status and antiviral treatment by performing whole genome sequencing on samples from 51 hepatitis B patients and by monitoring changes in deletion variants during treatment. Clone sequencing was used to analyze preS regions in another cohort of 52 patients. RESULTS: Among the core, preS, and basic core promoter (BCP) deletion hotspots, we identified preS to have the highest frequency and the most complex deletion pattern using whole genome sequencing. Further clone sequencing analysis on preS identified 70 deletions which were classified into 4 types, the most common being preS2. Also, in contrast to the core and BCP regions, most preS deletions were in-frame. Most deletions interrupted viral surface epitopes, and are possibly involved in evading immuno-surveillance. Among various clinical factors examined, logistic regression showed that antiviral medication affected the accumulation of deletion mutants (OR = 6.81, 95%CI = 1.296 ~ 35.817, P = 0.023). In chronic carriers of the virus, and individuals with chronic hepatitis, the deletion rate was significantly higher in the antiviral treatment group (Fisher exact test, P = 0.007). Particularly, preS2 deletions were associated with the usage of nucleos(t)ide analog therapy (Fisher exact test, P = 0.023). Dynamic increases in preS1 or preS2 deletions were also observed in quasispecies from samples taken from patients before and after three months of ADV therapy. In vitro experiments demonstrated that preS2 deletions alone were not responsible for antiviral resistance, implying the coordination between wild type and mutant strains during viral survival and disease development. CONCLUSIONS: We present the HBV deletion distribution patterns and preS deletion substructures in viral genomes that are prevalent in northern China. The accumulation of preS deletion mutants during nucleos(t)ide analog therapy may be due to viral escape from host immuno-surveillance.

Concepts: Deletion, Antiviral drug, Gene, Cirrhosis, Virus, Hepatitis, DNA, Hepatitis B

169

BACKGROUND: A higher prevalence of coeliac disease has recently been reported among patients with HCV-related chronic hepatitis. Moreover, development of clinically overt coeliac disease has been described in a number of HCV-related chronic hepatitis patients during alpha-interferon therapy. This prospective study was designed to evaluate 1) the prevalence of coeliac disease in patients with HCV-related chronic hepatitis; 2) the prevalence of HCV infection in patients with coeliac disease; 3) whether PEG interferon-alpha treatment might favour the development of coeliac disease in patients with chronic hepatitis C.Materials and methodsTwo hundred-ten consecutive patients (M/F = 140/70, range of age 35–58 years, median age 46.5 years) with biopsy proven chronic hepatitis C underwent serological screening for antiendomysial and tissue transglutaminase IgA antibodies. One hundred ninety-four coeliac patients (M/F = 52/142, range of age 18–74 years, median age 34 years) were screened for HCV antibodies. Positivity for HCV antibodies in coeliac disease patients was confirmed by detection of serum HCV-RNA by RT-PCR. This work was carried out in accordance to ethical guidelines of Declaration of Helsinki and was approved by Institutional Ethics Committee of the Second University of Naples. All patients gave informed written consent. RESULTS: 1) none of the 210 HCV-related chronic hepatitis patients were positive for coeliac disease serologic screening; 2) prevalence of HCV infection among coeliac patients was 1.54% (3/194) which is comparable to that reported in the Southern Italy population; 3) PEG interferon-alpha treatment was not associated with development of coeliac disease either clinical or serological. CONCLUSIONS: 1) coeliac disease is not associated with HCV infection; 2) PEG interferon-alpha does not trigger celiac disease.

Concepts: Immune system, Antibody, Osteoporosis, Anti-transglutaminase antibodies, Hepatitis B, Coeliac disease, Tissue transglutaminase, Hepatitis C

169

BACKGROUND: There is agreement that the infectivity assay with the duck hepatitis B virus (DHBV) is a suitable surrogate test to validate disinfectants for hepatitis B virucidal activity. However, since this test is not widely used, information is necessary whether disinfectants with limited virucidal activity also inactivate DHBV. In general, disinfectants with limited virucidal activity are used for skin and sensitive surfaces while agents with full activity are more aggressive. The present study compares the activity of five different biocides against DHBV and the classical test virus for limited virucidal activity, the vaccinia virus strain Lister Elstree (VACV) or the modified vaccinia Ankara strain (MVA). METHODS: Virucidal assay was performed as suspension test according to the German DVV/RKI guideline. Duck hepatitis B virus obtained from congenitally infected Peking ducks was propagated in primary duck embryonic hepatocytes and was detected by indirect immunofluorescent antigen staining. RESULTS: The DHBV was inactivated by the use of 40% ethanol within 1-min and 30% isopropanol within 2-min exposure. In comparison, 40% ethanol within 2-min and 40% isopropanol within 1-min exposure were effective against VACV/MVA. These alcohols only have limited virucidal activity, while the following agents have full activity. 0.01% peracetic acid inactivated DHBV within 2 min and a concentration of 0.005% had virucidal efficacy against VACV/MVA within 1 min. After 2-min exposure, 0.05% glutardialdehyde showed a comparable activity against DHBV and VACV/MVA. This is also the case for 0.7% formaldehyde after a contact time of 30 min. CONCLUSIONS: Duck hepatitis B virus is at least as sensitive to limited virucidal activity as VACV/MVA. Peracetic acid is less effective against DHBV, while the alcohols are less effective against VACV/MVA. It can be expected that in absence of more direct tests the results may be extrapolated to HBV.

Concepts: Ethanol, Hepadnaviridae, Vaccinia, Modified vaccinia Ankara, Alcohol, Viruses, Virus, Hepatitis B

166

The clinical relevance of single nucleotide polymorphisms (SNPs) near the gene is controversial in patients with hepatitis B virus (HBV) infection. This study aimed to investigate the role of viral and host factors, including genotypes, in the natural course of chronic hepatitis B (CHB).

Concepts: Hepatitis C, Gene, Hepatitis A, Genetics, Cirrhosis, Hepatitis, DNA, Hepatitis B

151

Hepatitis C is a disease caused by hepatitis C virus (HCV) that causes chronic infection, cirrhosis, and hepatocellular carcinoma. The current standard therapy is a combination of pegylated interferon-α plus ribavirin with NS3 protease inhibitors. Addition of NS3 protease inhibitors increases response rates; however, this addition is associated with significant side effects and an increase in the overall cost of the treatment. Therefore, there remains a need to develop safe and inexpensive drugs for the treatment of HCV infections. In this study, we examined the antiviral activity of a crude extract from Dimocarpus longan leaves against HCV (genotype 2a strain JFH1). The D. longan crude extract exhibited anti-HCV activity with a 50% effective concentration (EC50) of 19.4 μg/ml without cytotoxicity. A time-of-addition study demonstrated that the crude extract exerts anti-HCV activity at both the entry and post-entry steps. The crude extract markedly blocked viral entry step through a direct virucidal effect with a marginal inhibition of virion assembly. The co-treatment of the crude extract with cyclosporine A or telaprevir, an NS3 protease inhibitor, had additive and synergistic antiviral effects, respectively. Our findings suggest that the D. longan crude extract may be a candidate of the add-on therapy for HCV infection.

Concepts: Antiretroviral drug, Cirrhosis, Immune system, Dimocarpus, Virus, Longan, Hepatitis B, Hepatitis C

139

Although a vaccine against hepatitis B virus (HBV) has been available since 1982, the prevalence of adults with chronic HBV infection in sub-Saharan Africa and East Asia is still estimated at 5-10%. A high rate of chronic infections is also found in the Amazon and the southern parts of eastern and central Europe. In the Middle East and the Indian subcontinent, the prevalence is 2-5%. Less than 1% of the population of Western Europe and North America is chronically infected. Given the high prevalence of infections (such as hepatitis) among inmates, prison is considered a reservoir for facilitating such infections. Based on these premises, this current review examines and discusses emerging trends in the epidemiology of HBV infection, with particular attention to HBV infection in prison. The hepatitis B surface antigen (HBsAg) prevalence in prisoners in west and central Africa is very high (23.5%). The Centers for Disease Control and Prevention has highlighted the importance of HBV blood screening and subsequent anti-HBV vaccination in the prison population. The vaccination was recommended for all inmates, representing an opportunity to prevent HBV infection in a high-risk population. In these subjects, an accelerated hepatitis B immunisation schedule may result in rapid seroconversion for early short-term protection. Therefore, it is necessary to seek collaboration among public health officials, clinicians and correctional authorities to implement a vaccination programme.

Concepts: Central Asia, Europe, Disease, Middle East, Asia, North Africa, Immune system, Hepatitis B