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1.
Acta Microbiol Immunol Hung ; 68(2): 87-91, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34125695

RESUMO

Widespread introduction of HIV integrase inhibitors into clinical care may result in appearance of drug resistance mutations affecting treatment outcome. The aim of our study was to monitor the resistance patterns of integrase inhibitors beside protease and reverse transcriptase inhibitors in newly diagnosed therapy-naive HIV-positive patients in Hungary between 2017 and 2019.Genotype-based resistance testing of HIV integrase, protease and reverse transcriptase was performed by amplification and Sanger population sequencing from plasma samples. Drug resistance mutations were identified by the algorithm of Stanford HIV Drug Resistance Database.Potentially transmitted, non-polymorphic integrase major mutation was detected in 1 out of 249 samples, while accessory mutations were observed in further 31 patients (12.4%). The overall prevalence of transmitted drug resistance (TDR) mutations related to protease and reverse transcriptase inhibitors was 5.8% (10/173) between the end of 2017 and 2019. Nucleoside reverse transcriptase inhibitor associated resistance mutations were the most frequent indicators of TDR (6/173; 3.5%), followed by resistance mutations associated with protease (3/173; 1.7%) and non-nucleoside reverse transcriptase inhibitors (2/173, 1.2%).The first detection of integrase major mutation and the changing patterns of other resistance mutations in Hungarian untreated HIV-positive population indicate the necessity of continuous molecular surveillance of Hungarian HIV epidemic.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , HIV-1 , Farmacorresistência Viral/genética , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/genética , Humanos , Hungria/epidemiologia , Mutação , Prevalência
2.
J Glob Antimicrob Resist ; 20: 124-130, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31330377

RESUMO

OBJECTIVES: Transmitted human immunodeficiency virus type 1 (HIV-1) drug resistance (TDR) may affect the success of first-line antiretroviral treatment. This study aimed to monitor the presence of HIV-1 strains carrying transmitted drug resistance-associated mutations (TDRMs) in newly diagnosed and treatment-naïve patients in Hungary. METHODS: This study included 168 HIV-infected individuals diagnosed between 2013-2017; most of them (93.5%) belonged to the homo/bisexual population. HIV-1 subtypes and TDRMs were determined by analysing the protease and reverse transcriptase coding regions of the pol gene by the Stanford HIV Drug Resistance Database. Transmission clusters among patients were identified using phylogenetic analysis. RESULTS: Although subtype B HIV-1 strains were predominant (87.5%), non-B subtypes including F, A, CRF01_AE, CRF02_AG, D and G were also recorded, especially in young adults. The overall prevalence of TDR was 10.7% (18 of 168; 95% CI: 6.9-16.3%). Subtype B HIV-1 strains carried most of the TDRMs (94.4%). Nucleoside reverse transcriptase inhibitor (NRTI)-associated mutations were the most prevalent indicators of TDR (16 of 168; 9.5%; 95% CI: 5.9-14.9%), followed by mutations conferring resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) (2 of 168; 1.2%; 95% CI: 0.3-4.2%) and protease inhibitors (PIs) (1 of 168, 0.6%; 95% CI: 0.1-3.3%). Phylogenetic analysis revealed that most NRTI-associated resistance mutations were associated with a single monophyletic clade, suggesting early single-source introduction and ongoing spread of this drug-resistant HIV-1 strain. CONCLUSIONS: Onward transmission of drug-resistant subtype B HIV-1 strains accounted for the majority of TDRs observed among treatment-naïve HIV-infected individuals in Hungary.


Assuntos
Farmacorresistência Viral , Infecções por HIV/transmissão , HIV-1/classificação , Mutação , Adulto , Fatores Etários , Bissexualidade/estatística & dados numéricos , Infecções por HIV/virologia , HIV-1/genética , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , Adulto Jovem
3.
Euro Surveill ; 24(19)2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31088600

RESUMO

BackgroundA steady increase in HIV drug resistance (HIVDR) has been demonstrated globally in individuals initiating first-line antiretroviral therapy (ART). To support effective use of ART and prevent spread of HIVDR, monitoring is essential.AimWe piloted a surveillance system for transmitted HIVDR to assess the feasibility of implementation at the European level.MethodAll 31 countries in the European Union and European Economic Area were invited to retrospectively submit data on individuals newly diagnosed with HIV in 2015 who were tested for antiviral susceptibility before ART, either as case-based or as aggregate data. We used the Stanford HIV database algorithm to translate genetic sequences into levels of drug resistance.ResultsNine countries participated, with six reporting case-based data on 1,680 individuals and four reporting aggregated data on 1,402 cases. Sequence data were available for 1,417 cases: 14.5% of individuals (n = 244) showed resistance to at least one antiretroviral drug. In case-based surveillance, the highest levels of transmitted HIVDR were observed for non-nucleoside reverse-transcriptase inhibitors (NNRTIs) with resistance detected in 8.6% (n = 145), followed by resistance to nucleoside reverse-transcriptase inhibitors (NRTI) (5.1%; n = 85) and protease inhibitors (2.0%; n = 34).ConclusionWe conclude that standard reporting of HIVDR data was feasible in the participating countries. Legal barriers for data sharing, consensus on definitions and standardisation of interpretation algorithms should be clarified in the process of enhancing European-wide HIV surveillance with drug resistance information.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Adulto , Fármacos Anti-HIV/uso terapêutico , Europa (Continente)/epidemiologia , União Europeia , Estudos de Viabilidade , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/genética , Humanos , Masculino , Projetos Piloto , Polimorfismo Genético , Vigilância da População , Prevalência
4.
Artigo em Inglês | MEDLINE | ID: mdl-30853999

RESUMO

Here we report the evaluation of the antiretroviral effect of two flavonoid 7-O-glucosides, herbacitrin (1) and gossypitrin (2), together with quercetin (3), a well-studied flavonol. Antiviral activity of the flavonoids was assessed by analyzing HIV-1 p24 core protein levels in the supernatants of HIV-1 infected MT-4 and MT-2 cell cultures. The compounds showed mild to weak cytotoxic activities on the host cells; herbacitrin was the strongest in this regard (CC50=27.8 and 63.64 µM on MT-4 and MT-2 cells, respectively). In nontoxic concentrations, herbacitrin and quercetin reduced HIV-1 replication, whereas gossypitrin was ineffective. Herbacitrin was found to inhibit reverse transcriptase at 21.5 µM, while it was a more potent integrase inhibitor already active at 2.15 µM. Therefore, our observations suggest that herbacitrin exerts antiretroviral activity through simultaneously acting on these two targets of HIV-1 and that integrase inhibition might play a major role in this activity.

5.
Rev Med Virol ; 26(1): 57-73, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26593760

RESUMO

Hepatitis B virus (HBV) is one of the causative agents of hepatocellular carcinoma. The molecular mechanisms of tumorigenesis are complex. One of the host factors involved is apparently the long-lasting inflammatory reaction which accompanies chronic HBV infection. Although HBV lacks a typical viral oncogene, the HBx gene encoding a pleiotropic regulatory protein emerged as a major player in liver carcinogenesis. Here we review the tumorigenic functions of HBx with an emphasis on wild type and truncated HBx variants, and their role in the transcriptional dysregulation and epigenetic reprogramming of the host cell genome. We suggest that HBx acquired by the HBV genome during evolution acts like a cellular proto-onc gene that is activated by deletion during hepatocarcinogenesis. The resulting viral oncogene (v-onc gene) codes for a truncated HBx protein that facilitates tumor progression. Copyright © 2015 John Wiley & Sons, Ltd.

6.
J Med Chem ; 57(10): 3939-65, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24742150

RESUMO

Although there is a significant effort in the design of a selective CDK9/CycT1 inhibitor, no compound has been proven to be a specific inhibitor of this kinase so far. The aim of this research was to develop novel and selective phosphorus containing CDK9/CycT1 inhibitors. Molecules bearing phosphonamidate, phosphonate, and phosphinate moieties were synthesized. Prepared compounds were evaluated in an enzymatic CDK9/CycT1 assay. The most potent molecules were tested in cell-based toxicity and HIV proliferation assays. Selectivity of shortlisted compounds against CDKs and other kinases was tested. The best compound was shown to be a highly specific, ATP-competitive inhibitor of CDK9/CycT1 with antiviral activity.


Assuntos
Antivirais/síntese química , Ciclina T/antagonistas & inibidores , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/síntese química , Antivirais/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Humanos , Fósforo , Inibidores de Proteínas Quinases/farmacologia , Relação Estrutura-Atividade
7.
AIDS Rev ; 15(3): 181-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24002202

RESUMO

We surveyed current trends in epigenetics in general and epigenetics of HIV infection and AIDS in particular to pinpoint promising areas for translational research. Epigenetic mechanisms mark and affect the structure of chromatin, thereby controlling the activity of promoters. Because epigenetic changes are reversible, epigenetic drugs can be used to modulate gene activity. At present, silenced HIV genomes, the latent HIV reservoir, is a major obstacle for a curative treatment of AIDS patients. Epigenetic therapy aims at the purging of the latent reservoir by switching on transcription of silent HIV genomes. The basic idea is that the cytopathic effect of the replicating virus and the immune system may eliminate the reactivated cells, whereas HAART may block the infection of new target cells. Although current efforts concentrate on long-lived resting memory CD4+ T-cells, dormant HIV proviruses also reside in other cell types. Thus, epigenetic characterization of the various HIV-infected host cells and host cell-dependent HIV latency mechanisms is a promising research area and may facilitate the development of cell type-specific epigenetic drugs. HAART itself affects the epigenotype of host cells. This may contribute to the development of drug resistance and unwanted side effects. A pharmacoepigenetic approach may help to elucidate and revert such phenomena. In addition to latent reservoir purging, epigenetic research offers alternative therapeutic tools as well; although not aimed at the elimination of the virus, targeted silencing of HIV transcription by epigenetic regulators may help HAART to minimize virus replication.


Assuntos
Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Epigenômica , Infecções por HIV/tratamento farmacológico , Terapia de Alvo Molecular , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Epigenômica/tendências , Feminino , Inativação Gênica , Infecções por HIV/genética , Humanos , Masculino , Terapia de Alvo Molecular/tendências , Pesquisa Translacional Biomédica/tendências , Latência Viral/genética
8.
Adv Exp Med Biol ; 711: 82-102, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21627044

RESUMO

Epstein-Barr virus (EBV) is ahumanherpesvirus thatpersists in the memory B-cells of the majority of the world population in a latent form. Primary EBV infection is asymptomatic or causes a self-limiting disease, infectious mononucleosis. Virus latency is associated with a wide variety of neoplasms whereof some occur in immune suppressed individuals. Virus production does not occur in strict latency. The expression of latent viral oncoproteins and nontranslated RNAs is under epigenetic control via DNA methylation and histone modifications that results either in a complete silencing of the EBV genome in memory B cells, or in a cell-type dependent usage of a couple of latency promoters in tumor cells, germinal center B cells and lymphoblastoid cells (LCL, transformed by EBV in vitro). Both, latent and lytic EBV proteins elicit a strong immune response. In immune suppressed and infectious mononucleosis patients, an increased viral load can be detected in the blood. Enhanced lytic replication may result in new infection- and transformation-events and thus is a risk factor both for malignant transformation and the development of autoimmune diseases. An increased viral load or a changed presentation of a subset of lytic or latent EBV proteins that cross-react with cellular antigens may trigger pathogenic processes through molecular mimicry that result in multiple sclerosis (MS), systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA).


Assuntos
Doenças Autoimunes/etiologia , Epigênese Genética , Herpesvirus Humano 4/genética , Latência Viral/genética , Sequência de Aminoácidos , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/virologia , Ilhas de CpG , Metilação de DNA , Humanos , Dados de Sequência Molecular
9.
AIDS Res Hum Retroviruses ; 27(11): 1243-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21453184

RESUMO

The aim of our study was to monitor the diversity of HIV-1 strains circulating in Hungary and investigate the prevalence of resistance-associated mutations to reverse transcriptase (RT) and protease (PR) inhibitors in newly diagnosed, drug-naive patients. A total of 30 HIV-1-infected patients without prior antiretroviral treatment diagnosed during the period 2008-2010 were included into this study. Viral subtypes and the presence of RT, PR resistance-associated mutations were established by sequencing. Classification of HIV-1 strains showed that 29 (96.6%) patients were infected with subtype B viruses and one patient (3.3%) with subtype A virus. The prevalence of HIV-1 strains with transmitted drug resistance mutations in newly diagnosed individuals was 16.6% (5/30). This study showed that HIV-1 subtype B is still highly predominant in Hungary and documented a relatively high transmission rate of drug resistance in our country.


Assuntos
Farmacorresistência Viral/genética , Genes env/genética , Genes pol/genética , Infecções por HIV/epidemiologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/genética , Adulto , Sequência de Aminoácidos , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/virologia , HIV-1/classificação , Humanos , Hungria/epidemiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Mutação , Alinhamento de Sequência , Análise de Sequência de DNA , Adulto Jovem
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