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1.
J Antimicrob Chemother ; 78(7): 1732-1739, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37254601

RESUMO

BACKGROUND: Panzi General Reference Hospital (HGR Panzi) in the Democratic Republic of Congo follows a large number of patients living with HIV-1 (PLWHIV). Although antiretrovirals (ARVs) are available, HIV-1 viral load (HIV-VL) measurement has only been implemented in the hospital since 2018. No data on ARV resistance levels and ARV dosage in plasma have yet been published for this region. We determined the prevalence of virological failure due to ARV resistance amongst patients and assessed the degree of genotypic resistance of the viral strains. METHODS: We performed an HIV-VL test and determined dosage of ARVs on samples collected from 205 PLWHIV at HGR Panzi between 2017 and 2018, including 13 ARV-naive patients. Genotypic resistance testing was performed on all samples with detectable HIV-VLs, and interpreted with the Agence Nationale de Recherches sur le Sida (ANRS) 2018 algorithm. RESULTS: Baseline resistance to NNRTIs was found in 2 of the 13 treatment-naive individuals (15%). ARV dosage was non-optimal for 44/192 of treated patients (22.9%), with an HIV-VL ≥1000 IU/mL for 40/192 (20.8%) of them. In particular, treatment-experienced viruses presented resistance to at least one NRTI (52.5%), to at least one NNRTIs (70%) or to at least one PIs (15%). Finally, two samples contained viruses with resistance polymorphism in the integrase gene. CONCLUSIONS: The high level of resistance to ARVs observed during this study, mainly due to treatment compliance default, fully justifies the implementation of means for closer patient monitoring. The provision of VL tests and therapeutic education management tools in a PLWHIV follow-up remains an absolute necessity to best adapt the current treatment lines in this region.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , HIV-1/genética , República Democrática do Congo/epidemiologia , Farmacorresistência Viral/genética , Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Soropositividade para HIV/tratamento farmacológico , Carga Viral , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico
2.
Front Microbiol ; 12: 751531, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867871

RESUMO

Human hepatitis Delta virus (HDV) infection is associated to the most severe viral hepatic disease, including severe acute liver decompensation and progression to cirrhosis, and hepatocellular carcinoma. HDV is a satellite of hepatitis B virus (HBV) that requires the HBV envelope proteins for assembly of HDV virions. HDV and HBV exhibit a large genetic diversity that extends, respectively to eight (HDV-1 to -8) and to ten (HBV/A to/J) genotypes. Molecular determinants of HDV virion assembly consist of a C-terminal Proline-rich domain in the large Hepatitis Delta Antigen (HDAg) protein, also known as the Delta packaging domain (DPD) and of a Tryptophan-rich domain, the HDV matrix domain (HMD) in the C-terminal region of the HBV envelope proteins. In this study, we performed a systematic genotyping of HBV and HDV in a cohort 1,590 HDV-RNA-positive serum samples collected between 2001 to 2014, from patients originated from diverse parts of the world, thus reflecting a large genetic diversity. Among these samples, 526 HBV (HBV/A, B, C, D, E, and G) and HDV (HDV-1, 2, 3, and 5 to -8) genotype couples could be obtained. We provide results of a comprehensive analysis of the amino-acid sequence conservation within the HMD and structural and functional features of the DPD that may account for the yet optimal interactions between HDV and its helper HBV.

3.
Viruses ; 13(8)2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34452437

RESUMO

Human hepatitis delta virus (HDV) is a small defective RNA satellite virus that requires hepatitis B virus (HBV) envelope proteins to form its own virions. The HDV genome possesses a single coding open reading frame (ORF), located on a replicative intermediate, the antigenome, encoding the small (s) and the large (L) isoforms of the delta antigen (s-HDAg and L-HDAg). The latter is produced following an editing process, changing the amber/stop codon on the s-HDAg-ORF into a tryptophan codon, allowing L-HDAg synthesis by the addition of 19 (or 20) C-terminal amino acids. The two delta proteins play different roles in the viral cell cycle: s-HDAg activates genome replication, while L-HDAg blocks replication and favors virion morphogenesis and propagation. L-HDAg has also been involved in HDV pathogenicity. Understanding the kinetics of viral editing rates in vivo is key to unravel the biology of the virus and understand its spread and natural history. We developed and validated a new assay based on next-generation sequencing and aimed at quantifying HDV RNA editing in plasma. We analyzed plasma samples from 219 patients infected with different HDV genotypes and showed that HDV editing capacity strongly depends on the genotype of the strain.


Assuntos
Genótipo , Vírus Delta da Hepatite/genética , Edição de RNA/genética , RNA Viral/sangue , Replicação Viral/genética , Genoma Viral/genética , Hepatite D/sangue , Hepatite D/virologia , Vírus Delta da Hepatite/classificação , Vírus Delta da Hepatite/metabolismo , Vírus Delta da Hepatite/patogenicidade , Antígenos da Hepatite delta/sangue , Antígenos da Hepatite delta/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Fases de Leitura Aberta
4.
Liver Int ; 41(7): 1509-1517, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33999515

RESUMO

Hepatitis delta virus (HDV) infection is the most severe form of viral hepatitis. Bulevirtide (BLV, Hepcludex® ) is an HDV/HBV entry inhibitor approved in June 2020 in the European Union for adult patients with chronic hepatitis delta (CHD) and compensated liver disease and positive HDV RNA viral load. This real-life preliminary report described early virological efficacy and safety of BLV in six patients with CHD and compensated liver disease: four patients were treated with the combination of BLV (2 mg/d in subcutaneous injection) and pegylated interferon (PEG-IFN) and two patients with BLV monotherapy. Four patients treated with combined therapy had a decline of a minimum of 1 log10 and 3/3 of 2 log10 of HDV-VL at 12 and 24 weeks, respectively. One patient among four had stopped the treatment at 12 weeks because of thrombocytopenia and an HDV-VL relapse was notified 24 weeks after treatment cessation. Three patients among four (3/4) had undetectable HDV-VL during the therapy (<100 IU/ml). One patient (1/2) treated with BLV monotherapy had a decline of HDV-VL by 1 log10 at 8 weeks and 1/1 by 2 log10 at 28 week on-treatment. Two patients among four (2/4) with combined therapy had normal ALT reached at 4 and 56 weeks. One patient (1/2) with BLV monotherapy achieves ALT normalization at​ 4 weeks on treatment. Hepatitis B surface antigen (HBsAg) levels remain unchanged. Three among six (3/6) patients had an elevation of total biliary acids without pruritus. These early data generated confirm the interest in this new treatment. Final results will be important to demonstrate long-term clinical benefit (fibrosis reversibility and reduction in hepato-cellular carcinoma [HCC]).


Assuntos
Carcinoma Hepatocelular , Hepatite D , Neoplasias Hepáticas , Adulto , Antivirais/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Hepatite D/tratamento farmacológico , Vírus Delta da Hepatite , Humanos , Cirrose Hepática/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Recidiva Local de Neoplasia
6.
J Med Virol ; 91(9): 1688-1692, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31081541

RESUMO

Hepatitis delta virus (HDV) is responsible for the most severe form of liver disease in humans. So far, eight genotypes (HDV-1 to -8) have been individualized worldwide. Little is known about HDV strains that spread in Nigeria. HDV genotyping was performed in 15 anti-HDV positive samples from a cohort of 306 hepatitis B virus (HBV)-infected patients in Abuja (Nigeria). Phylogenetic analyses revealed 90% were HDV-1, two among them clustering with European/Asian HDV-1, the remaining one being HDV-6. It was also found that two members of a couple superinfected with the same HDV strain, were enveloped by two different HBV strains of genotype E.


Assuntos
Hepatite D/epidemiologia , Hepatite D/virologia , Vírus Delta da Hepatite/genética , Coinfecção , Feminino , Genótipo , Anticorpos Anti-Hepatite , Vírus Delta da Hepatite/classificação , Humanos , Masculino , Nigéria/epidemiologia , Filogenia , Prevalência , RNA Viral , Análise de Sequência de DNA , Carga Viral
7.
J Viral Hepat ; 26(1): 170-182, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30141209

RESUMO

Although central Africa is classified as having a high endemicity of hepatitis B virus (HBV) and hepatitis D virus (HDV) infection, there is paucity of prevalence studies. For the first time on a country-wide level in Central Africa, we show in Gabon an overall 7.4% prevalence of Hepatitis B surface antigen (HBsAg) and that more than 25% of the HBsAg-positive population are infected by HDV. Although HBV prevalence did not differ significantly between provinces, there is a north-south split in the distribution of HDV seroprevalence, with the highest rates (>66.0%) correlating with the presence of specific ethnic groups in the northeastern provinces. Genotyping revealed high genetic diversity of the HBV and HDV strains circulating in Gabon, including many restricted to this region of the globe. This work confirmed that high exposure to HBV and HDV infection reported in selected regions of Gabon holds true across the whole country.


Assuntos
Variação Genética , Vírus da Hepatite B/genética , Hepatite B/epidemiologia , Hepatite D/epidemiologia , Vírus Delta da Hepatite/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Gabão/epidemiologia , Genótipo , Anticorpos Anti-Hepatite/sangue , Anticorpos Anti-Hepatite/imunologia , Hepatite B/imunologia , Hepatite D/imunologia , Vírus Delta da Hepatite/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , RNA Viral/genética , Fatores de Risco , Análise de Sequência de DNA , Estudos Soroepidemiológicos , Adulto Jovem
8.
PLoS Negl Trop Dis ; 12(4): e0006377, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29698488

RESUMO

Hepatitis delta virus (HDV) increases morbidity in Hepatitis B virus (HBV)-infected patients. In the mid-eighties, an outbreak of HDV fulminant hepatitis (FH) in the Central African Republic (CAR) killed 88% of patients hospitalized in Bangui. We evaluated infections with HBV and HDV among students and pregnant women, 25 years after the fulminant hepatitis (FH) outbreak to determine (i) the prevalence of HBV and HDV infection in this population, (ii) the clinical risk factors for HBV and/or HDV infections, and (iii) to characterize and compare the strains from the FH outbreak in the 1980s to the 2010 HBV-HDV strains. We performed a cross sectional study with historical comparison on FH-stored samples (n = 179) from 159 patients and dried blood-spots from volunteer students and pregnant women groups (n = 2172). We analyzed risk factors potentially associated with HBV and HDV. Previous HBV infection (presence of anti-HBc) occurred in 345/1290 students (26.7%) and 186/870 pregnant women (21.4%)(p = 0.005), including 110 students (8.8%) and 71 pregnant women (8.2%), who were also HBsAg-positive (p = 0.824). HDV infection occurred more frequently in pregnant women (n = 13; 18.8%) than students (n = 6; 5.4%) (p = 0.010). Infection in childhood was probably the main HBV risk factor. The risk factors for HDV infection were age (p = 0.040), transfusion (p = 0.039), and a tendency for tattooing (p = 0.055) and absence of condom use (p = 0.049). HBV-E and HDV-1 were highly prevalent during both the FH outbreak and the 2010 screening project. For historical samples, due to storage conditions and despite several attempts, we could only obtain partial HDV amplification representing 25% of the full-length genome. The HDV-1 mid-eighties FH-strains did not form a specific clade and were affiliated to two different HDV-1 African subgenotypes, one of which also includes the 2010 HDV-1 strains. In the Central African Republic, these findings indicate a high prevalence of previous and current HBV-E and HDV-1 infections both in the mid-eighties fulminant hepatitis outbreak and among asymptomatic young adults in 2010, and reinforce the need for universal HBV vaccination and the prevention of HDV transmission among HBsAg-positive patients through blood or sexual routes.


Assuntos
Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Hepatite D/virologia , Vírus Delta da Hepatite/isolamento & purificação , Adolescente , Adulto , República Centro-Africana/epidemiologia , Estudos Transversais , Surtos de Doenças/história , Feminino , Genótipo , Hepatite B/epidemiologia , Hepatite B/história , Hepatite B/transmissão , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite D/epidemiologia , Hepatite D/história , Hepatite D/transmissão , Vírus Delta da Hepatite/classificação , Vírus Delta da Hepatite/genética , Vírus Delta da Hepatite/fisiologia , História do Século XX , História do Século XXI , Humanos , Masculino , Filogenia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/virologia , Adulto Jovem
9.
Liver Int ; 38(6): 1000-1009, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28980394

RESUMO

BACKGROUND & AIMS: Hepatitis D virus (HDV) infection is associated with a more severe outcome in patients with chronic hepatitis B (CHB); however, little is known about the presence of HDV in sub-Saharan Africa. We aimed to determine the prevalence of HDV infection, as well as its clinical, biological and virological characteristics, in a large CHB cohort in Ethiopia. METHODS: In total, 1267 HIV-negative CHB patients at St. Paul's Hospital Millennium Medical College in Addis Ababa were screened for anti-HDV antibodies using ELISA assays. Confirmed positive samples were further tested for HDV RNA using a consensus commercial real-time RT-PCR assay. HDV genotypes were also determined for RNA-positive samples by nucleotide sequencing followed by phylogenetic analyses. Demographical, clinical and biological data from patients were recorded and compared based on HDV RNA results. RESULTS: Most patients (n = 748, 59.0%) were men, and the median age was 31 years (interquartile range 26-40). Anti-HDV antibodies were detected in 19 individuals (1.5%), 12 of whom were HDV RNA-positive with a viral load ranging from <2 to >8 log 10 IU/mL. All strains were genotype 1. HDV RNA-positive patients were more likely to have significant liver fibrosis (63.6% vs 24.7%, P = .007) and cirrhosis (45.5% vs 16.4%, P = .024). CONCLUSIONS: HDV infection is rare in Ethiopia but is associated with more advanced liver fibrosis.


Assuntos
Coinfecção/virologia , Hepatite B Crônica/complicações , Hepatite D/epidemiologia , Vírus Delta da Hepatite/genética , Cirrose Hepática/virologia , Adolescente , Adulto , Estudos de Coortes , Coinfecção/mortalidade , Ensaio de Imunoadsorção Enzimática , Etiópia/epidemiologia , Feminino , Anticorpos Anti-Hepatite/sangue , Hepatite D/mortalidade , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral , Adulto Jovem
10.
J Clin Microbiol ; 55(5): 1299-1312, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28202798

RESUMO

The majority of patients with acute febrile jaundice (>95%) identified through a yellow fever surveillance program in the Democratic Republic of Congo (DRC) test negative for antibodies against yellow fever virus. However, no etiological investigation has ever been carried out on these patients. Here, we tested for hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), hepatitis D (HDV), and hepatitis E (HEV) viruses, all of which can cause acute febrile jaundice, in patients included in the yellow fever surveillance program in the DRC. On a total of 498 serum samples collected from suspected cases of yellow fever from January 2003 to January 2012, enzyme-linked immunosorbent assay (ELISA) techniques were used to screen for antibodies against HAV (IgM) and HEV (IgM) and for antigens and antibodies against HBV (HBsAg and anti-hepatitis B core protein [HBc] IgM, respectively), HCV, and HDV. Viral loads and genotypes were determined for HBV and HVD. Viral hepatitis serological markers were diagnosed in 218 (43.7%) patients. The seroprevalences were 16.7% for HAV, 24.6% for HBV, 2.3% for HCV, and 10.4% for HEV, and 26.1% of HBV-positive patients were also infected with HDV. Median viral loads were 4.19 × 105 IU/ml for HBV (range, 769 to 9.82 × 109 IU/ml) and 1.4 × 106 IU/ml for HDV (range, 3.1 × 102 to 2.9 × 108 IU/ml). Genotypes A, E, and D of HBV and genotype 1 of HDV were detected. These high hepatitis prevalence rates highlight the necessity to include screening for hepatitis viruses in the yellow fever surveillance program in the DRC.


Assuntos
Anticorpos Antivirais/imunologia , Hepacivirus/isolamento & purificação , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Vírus Delta da Hepatite/isolamento & purificação , Vírus da Hepatite E/isolamento & purificação , Febre Amarela/virologia , Vírus da Febre Amarela/isolamento & purificação , República Democrática do Congo , Ensaio de Imunoadsorção Enzimática , Hepacivirus/imunologia , Vírus da Hepatite A/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Vírus Delta da Hepatite/imunologia , Vírus da Hepatite E/imunologia , Humanos , Icterícia/diagnóstico , Icterícia/virologia , Estudos Soroepidemiológicos , Carga Viral , Febre Amarela/complicações , Vírus da Febre Amarela/imunologia
11.
J Clin Microbiol ; 55(2): 431-441, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27881614

RESUMO

Hepatitis D virus (HDV) is responsible for fulminant hepatitis and liver failure and accelerates evolution toward cirrhosis and hepatocellular carcinoma in hepatitis B virus (HBV)-infected patients. To date, treatment relies upon long-term administration of pegylated alpha-interferon with a sustained virological response in 30% of the patients. Very recently, new, promising anti-HDV therapies have been developed and are already being used in clinical trials. HDV RNA viral load (HDVL) monitoring must be an integral part of the management of the infected patients. However, HDV genus is characterized by a high genetic variability into eight genotypes (HDV-1 to -8), and most available in-house or commercial assays are useful for only a limited subset of genotypes. Results of a comparison of the performance of a new kit for HDVL quantification with the consensus in-house assay of the French National Reference Laboratory for HDV developed in 2005 are reported here. A total of 611 clinical samples of all HDV genotypes with various HDVL values, including several consecutive samples over several years from 36 patients, were studied. A specificity, sensitivity, and reproducibility evaluation was conducted using HDV-positive clinical samples, hepatitis A, B, C and E (HAV, HBV, HCV, and HEV, respectively) and HIV mono-infected samples, and the WHO HDV RNA international standard. Overall results were strictly comparable between the two assays (median difference, 0.07 log IU/ml), with high diagnosis precision and capacity. In summary, this new kit showed high performance in detection/quantification of HDVL, regardless of the genotype of the infecting strain used, and seems to be a suitable tool for patient management.


Assuntos
Hepatite D/virologia , Vírus Delta da Hepatite/isolamento & purificação , RNA Viral/análise , Kit de Reagentes para Diagnóstico , Carga Viral/métodos , Humanos , Estudos Longitudinais , RNA Viral/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Nucleic Acids Res ; 44(18): 8826-8841, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27580715

RESUMO

The discovery of novel specific ribosome-associated factors challenges the assumption that translation relies on standardized molecular machinery. In this work, we demonstrate that Tma108, an uncharacterized translation machinery-associated factor in yeast, defines a subpopulation of cellular ribosomes specifically involved in the translation of less than 200 mRNAs encoding proteins with ATP or Zinc binding domains. Using ribonucleoparticle dissociation experiments we established that Tma108 directly interacts with the nascent protein chain. Additionally, we have shown that translation of the first 35 amino acids of Asn1, one of the Tma108 targets, is necessary and sufficient to recruit Tma108, suggesting that it is loaded early during translation. Comparative genomic analyses, molecular modeling and directed mutagenesis point to Tma108 as an original M1 metallopeptidase, which uses its putative catalytic peptide-binding pocket to bind the N-terminus of its targets. The involvement of Tma108 in co-translational regulation is attested by a drastic change in the subcellular localization of ATP2 mRNA upon Tma108 inactivation. Tma108 is a unique example of a nascent chain-associated factor with high selectivity and its study illustrates the existence of other specific translation-associated factors besides RNA binding proteins.


Assuntos
Aminopeptidases/metabolismo , Biossíntese de Proteínas , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Trifosfato de Adenosina/metabolismo , Aminopeptidases/química , Hibridização in Situ Fluorescente , Mitocôndrias/genética , Mitocôndrias/metabolismo , Elongação Traducional da Cadeia Peptídica , Ligação Proteica , ATPases Translocadoras de Prótons/genética , Transporte de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Ribossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Zinco/metabolismo
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