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1.
Virology ; 585: 100-108, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37327595

RESUMO

BACKGROUND: JC polyomavirus (JCV) has an ethno-geographical distribution across human populations. OBJECTIVE: Study the origins of the population of Misiones (Argentina) by using JCV as genetic marker. METHODS: Viral detection and characterization was conducted by PCR amplification and evolutionary analysis of the intergenic region sequences. RESULTS: 22 out of 121 samples were positive for JCV, including 5 viral lineages: MY (n = 8), Eu-a (n = 7), B1-c (n = 4), B1-b (n = 2) and Af2 (n = 1). MY sequences clustered within a branch of Native American origin that diverged from its Asian counterpart about 21,914 years ago (HPD 95% interval 15,383-30,177), followed by a sustained demographic expansion around 5000 years ago. CONCLUSIONS: JCV in Misiones reflects the multiethnic origin of the current population, with an important Amerindian contribution. Analysis of the MY viral lineage shows a pattern consistent with the arrival of early human migrations to the Americas and a population expansion by the pre-Columbian native societies.


Assuntos
Vírus JC , Humanos , Vírus JC/genética , Evolução Biológica , Dinâmica Populacional , Migração Humana , América/epidemiologia , DNA Viral/genética
2.
Front Public Health ; 10: 995249, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324442

RESUMO

Background: Management of the coronavirus disease 2019 (COVID-19) pandemic caused by a novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) requires rapid and simple methods to detect COVID-19 patients and identify potential infectors. This study aimed to evaluate the utility of a point-of-care (PoC) rapid antigen diagnostic test (Ag-RDT) in these settings. Patients and methods: Individuals who consecutively presented for SARS-CoV-2 testing at a tertiary care center in Buenos Aires, Argentina, underwent PoC Ag-RDT testing and real-time RT-PCR (qRT-PCR) on the same day during June 2021. Results: Of 584 included subjects, 108 (18.5%) were symptomatic for COVID-19 while the remaining presented for miscellaneous reasons unrelated to possible or confirmed contact with a SARS-CoV-2-infected individual. A positive Ag-RDT result was obtained in 26 (24.1%) symptomatic and 7 (1.5%) asymptomatic persons (p < 0.001), which was concordant with qRT-PCR in 105/108 [97.2%, Cohen's kappa coefficient (κ) = 0.927] symptomatic and 467/476 (98.1% κ = 0.563) asymptomatic participants, with a positive percentage agreement (PPA; 95% confidence interval) of 89.7% (71.5-97.3%) and 42.9% (18.8-70.4%), respectively. None of the 11 false-negative diagnoses showed a Ct-value ≤20. Considering only failures with a Ct-value below 31 as hypothetical infectivity threshold of 105 SARS-CoV-2 RNA copies/mL, concordance was observed in 98.1% (κ = 0.746) in the asymptomatic population, accounting for a PPA of 66.7% (30.9-91%). Conclusions: PoC Ag-RDT accurately detected active SARS-CoV-2 infection and showed acceptable diagnostic performance in asymptomatic persons potentially spreading infectious virus. Ag-RDT may therefore be useful to slow down or stop transmission by enabling adequate decisions on isolation at a public health level.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , Teste para COVID-19 , Sistemas Automatizados de Assistência Junto ao Leito , RNA Viral/análise , Sensibilidade e Especificidade
4.
Clin Microbiol Infect ; 28(10): 1382-1388, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35595128

RESUMO

OBJECTIVES: To compare the homologous prime-boost vaccination scheme of Gam-COVID-Vac (Sputnik V (SpV)) to its heterologous combination with mRNA-1273 (Moderna (Mod)) vaccine. METHODS: SARS-CoV-2 anti-spike (S)-receptor binding domain (RBD) IgG concentration was assessed three to seven weeks after complete vaccination. Reactogenicity was evaluated by declared side events and medical assistance required until day 7 post boost. RESULTS: Of 190 participants enrolled, 105 received homologous SpV/SpV and the remaining heterologous SpV/Mod vaccination scheme, respectively. Median (interquartile range (IQR)) age was 54 (37-63) years, 132 out of 190 (69.5%) were female, and 46 out of 190 (24.2%) individuals had a prior confirmed COVID-19. Anti-S-RBD IgG median (IQR) titers were significantly higher for SpV/Mod (2511 (1476-3992) binding antibody units (BAU)/mL) than for SpV/SpV (582 (209-1609) BAU/mL; p < 0.001] vaccination scheme. In a linear model adjusted for age, gender, time to the serological assay, and time between doses, SpV/Mod (4.154 (6.585-615.554); p < 0.001] and prior COVID (3.732 (8.641-202.010); p < 0.001) were independently associated with higher anti-S-RBD IgG values. A higher frequency of mild and moderate adverse effects was associated with the heterologous scheme (20 of 85 (23.5%) vs. 13 of 105 (12.4%); p = 0.043 and 27 of 85 (31.8%) vs. 14 of 105 (13.3%); p = 0.002), respectively, although it was well tolerated by all individuals and no medical assistance was required. DISCUSSION: The heterologous SpV/Mod combination against SARS-CoV-2 is well tolerated and significantly increases humoral immune response as compared to the homologous SpV/SpV immunization.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , COVID-19 , Vacina de mRNA-1273 contra 2019-nCoV/efeitos adversos , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Análise de Dados , Feminino , Humanos , Imunoglobulina G , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/genética
6.
J Med Virol ; 93(5): 3000-3006, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33512021

RESUMO

The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become the main target for antiviral and vaccine development. Despite its relevance, e information is scarse about its evolutionary traces. The aim of this study was to investigate the diversification patterns of the spike for each clade of SARS-CoV-2 through different approaches. Two thousand and one hundred sequences representing the seven clades of the SARS-CoV-2 were included. Patterns of genetic diversifications and nucleotide evolutionary rate were estimated for the spike genomic region. The haplotype networks showed a star shape, where multiple haplotypes with few nucleotide differences diverge from a common ancestor. Four hundred seventy-nine different haplotypes were defined in the seven analyzed clades. The main haplotype, named Hap-1, was the most frequent for clades G (54%), GH (54%), and GR (56%) and a different haplotype (named Hap-252) was the most important for clades L (63.3%), O (39.7%), S (51.7%), and V (70%). The evolutionary rate for the spike protein was estimated as 1.08 × 10-3 nucleotide substitutions/site/year. Moreover, the nucleotide evolutionary rate after nine months of the pandemic was similar for each clade. In conclusion, the present evolutionary analysis is relevant as the spike protein of SARS-CoV-2 is the target for most therapeutic candidates; besides, changes in this protein could have consequences on viral transmission, response to antivirals and efficacy of vaccines. Moreover, the evolutionary characterization of clades improves knowledge of SARS-CoV-2 and deserves to be assessed in more detail as re-infection by different phylogenetic clades has been reported.


Assuntos
Evolução Molecular , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/virologia , Genoma Viral , Humanos , Pandemias , Filogenia , Glicoproteína da Espícula de Coronavírus/classificação
7.
J Med Virol ; 93(6): 4015-4017, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32639583

RESUMO

The aim of this study was to assess the prevalence of hepatitis E virus (HEV) in a young population from the Northeast region of Argentina. Four hundred and twelve patients under 18 years old, from rural areas of Chaco Province, were tested for anti-HEV immunoglobulin G (IgG) using enzyme-linked immunosorbent assay. Anti-HEV IgG antibodies were detected in 7 out of 412 patients, accounting for an overall 1.7% prevalence. HEV infection in developing countries is associated to lack of clean drinking water. Consequently, the seroprevalence observed in children in rural areas of Chaco, Argentina, where the access to tap water is less than 15%, was unexpectedly low.


Assuntos
Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite E/epidemiologia , Hepatite E/imunologia , Adolescente , Argentina , Criança , Estudos Transversais , Água Potável/virologia , Feminino , Hepatite E/transmissão , Vírus da Hepatite E/genética , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Prevalência , Estudos Retrospectivos , Fatores de Risco , População Rural , Estudos Soroepidemiológicos
8.
Eur J Gastroenterol Hepatol ; 33(10): 1322-1326, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32675777

RESUMO

BACKGROUND: Hepatitis E virus (HEV) is the main cause of enteric acute viral hepatitis worldwide. In this epidemiological framework, it has become a threat to blood safety and a relevant issue for blood transfusions. However, there is a paucity of data regarding prevalence of HEV infection. The aim of this study was to determine HEV seroprevalence in blood donors from different regions from Argentina. MATERIAL AND METHODS: Serum samples from 391 individuals attending five blood donor centers located in different regions from Argentina were analyzed for anti-HEV IgG and anti-HEV IgM. RESULTS: Overall, anti-HEV IgG was detected in 44 out of 391 (11.3%) samples. HEV prevalence ranged from 5.1 to 20.0% among different country regions. A significant difference in blood donors' age was observed between anti-HEV IgG positive and negative individuals [44 (37-51) vs. 35 (27-43), P < 0.001, respectively]. Anti-HEV IgM was detected in 8 out of 44 (18.2%) anti-HEV IgG positive cases. CONCLUSION: Anti-HEV IgG was detected in blood donor samples from five analyzed Argentinean regions, highlighting the wide distribution of the virus in the country. HEV prevalence was variable among different regions and significantly higher in older donors. Given the evidence of anti-HEV IgM presence in blood donors, suggesting a potential risk of transfusion-transmitted HEV, screening for HEV in blood units to be used in vulnerable population would be desirable. Molecular studies for detection of viremic donors and donor-recipients follow-up are necessary to certainly determine the risk of transfusion-transmitted HEV in Argentina.


Assuntos
Vírus da Hepatite E , Hepatite E , Idoso , Doadores de Sangue , Anticorpos Anti-Hepatite , Hepatite E/diagnóstico , Hepatite E/epidemiologia , Humanos , Imunoglobulina M , RNA Viral , Estudos Soroepidemiológicos
9.
J Med Virol ; 93(3): 1722-1731, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32966646

RESUMO

During the first few months of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evolution in a new host, contrasting hypotheses have been proposed about the way the virus has evolved and diversified worldwide. The aim of this study was to perform a comprehensive evolutionary analysis to describe the human outbreak and the evolutionary rate of different genomic regions of SARS-CoV-2. The molecular evolution in nine genomic regions of SARS-CoV-2 was analyzed using three different approaches: phylogenetic signal assessment, emergence of amino acid substitutions, and Bayesian evolutionary rate estimation in eight successive fortnights since the virus emergence. All observed phylogenetic signals were very low and tree topologies were in agreement with those signals. However, after 4 months of evolution, it was possible to identify regions revealing an incipient viral lineage formation, despite the low phylogenetic signal since fortnight 3. Finally, the SARS-CoV-2 evolutionary rate for regions nsp3 and S, the ones presenting greater variability, was estimated as 1.37 × 10-3 and 2.19 × 10-3 substitution/site/year, respectively. In conclusion, results from this study about the variable diversity of crucial viral regions and determination of the evolutionary rate are consequently decisive to understand essential features of viral emergence. In turn, findings may allow the first-time characterization of the evolutionary rate of S protein, crucial for vaccine development.


Assuntos
Evolução Biológica , Proteases Semelhantes à Papaína de Coronavírus/genética , Evolução Molecular , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Substituição de Aminoácidos/genética , Animais , COVID-19/patologia , Quirópteros/virologia , Genoma Viral/genética , Humanos , Filogenia
10.
J Med Microbiol ; 70(1)2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33180017

RESUMO

Introduction. Blood-borne infections are a major cause of harm in individuals on haemodialysis (HD). In particular, knowledge about hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV) status in HD patients is a major concern, since these infections may cause comorbidities in this setting. There is a paucity of data regarding this issue in Argentina.Hypothesis/Gap Statement. The epidemiological surveillance of HBV, HCV, and HIV is a fundamental tool for planning and implementing health strategies in order to prevent and control viral transmission of these viral agents.Aim. To determine the seroprevalence of HBV, HCV and HIV infections in HD patients in Buenos Aires, Argentina.Methodology. Seven hundred and forty-eight HD patients were included in a retrospective cross-sectional study. Serological assays were performed to determine HBV, HCV and HIV status. HBV HBsAg and anti-HBc IgG were analysed using AxSYM (samples before 2010) or the Architect Abbott system (samples since 2010), anti-HCV IgG testing was performed using the anti-HCV enzyme immunoassay AxSYM HCV V3.0 and ARCHITECT anti-HCV, while HIV was tested for using AxSYM HIV 1/2 gO and ARCHITECT HIV Ag/Ab Combination. HCV genotyping was carried out by phylogenetic analysis of the NS5B partial gene.Results. Infection with one of the viruses was detected in 31.1 % of patients [HBV in 82 (11.0 %), HCV in 179 (23.9 %) and HIV in 6 (0.8 %)]. Thirty-two (4.3 %) patients had 2 virus markers [27 (3.6 %) with HCV/HBV, 4 (0.5 %) with HCV/HIV and 1 (0.13 %) with HBV/HIV]. Finally, a single patient (0.13 %) presented all three markers. Time on dialysis was correlated with HCV but not with HBV infection. The HCV subtype distribution in HD patients was inverted with respect to that observed in the general population (HCV-1a 73.2 % and HCV-1b 26.8 % in HD vs HCV-1a 26.5 % and HCV-1b 73.5 % in the general population, P <0.001).Conclusion. Despite the implementation of universal precautionary biosafety standards for dialysis, infection with HBV and HCV continues to occur at very high rates in HD patients. The results emphasize the need to carry out proactive tasks for early diagnosis and treatment of infected individuals and to vaccinate those with non-protective antiHBs antibodies in order to reduce morbidity and mortality in HD patients.


Assuntos
Anticorpos Antivirais/sangue , Infecções por HIV/sangue , Hepatite B/sangue , Hepatite C/sangue , Adulto , Idoso , Argentina/epidemiologia , Estudos Transversais , Monitoramento Epidemiológico , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , HIV-1/imunologia , HIV-1/isolamento & purificação , Hepacivirus/classificação , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Hepatite B/epidemiologia , Hepatite B/virologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite C/epidemiologia , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Estudos Soroepidemiológicos
11.
Vaccine ; 38(12): 2678-2682, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32061386

RESUMO

Universal vaccination is the most effective strategy to control hepatitis B virus (HBV) infection. In Argentina, vaccination against HBV was incorporated in year 2000 for newborns and in 2003 for 11 years old children. However, there is a paucity of data about protection levels against HBV infection. The aim of this work was to determine the prevalence of seroprotective anti-HBs antibodies (aHBs) in Argentina. Serum samples negative for HBsAg and anti-HBc from 132 children born after year 2000 and 762 blood donors, older than 18 years, from five centers across the country, were analyzed for aHBs. Titers ≥10 mIU/mL were observed in 74/132 children (56.1%) and 336/762 (44.1%) in blood donors. The median age for blood donors was 33.9 (23-43); from them, 210 (27.6%) were born after 1992 and, therefore, were catch-up by vaccine implementation at 11 years old age. Donors born in 1992 or before showed a significantly lower frequency of protection (32.2%) compared to donors born after 1992 (75.2%), p < 0.0001. In addition, significant differences were observed in the status of seroprotection between different participating centers (p = 0.024). Implementation of HBV vaccine in 2000 and 2003 implied an overall increase of the aHBs seroprotective rates, with a particularly adequate response in children vaccinated at 11 years old age. The observed results suggest that population born in 1992 or before is currently the most susceptible. Consequently, it would be advisable to become aware of the risk of transmission in this age group and to stress this population vaccination campaigns.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Adolescente , Adulto , Fatores Etários , Argentina/epidemiologia , Doadores de Sangue , Criança , Pré-Escolar , Feminino , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
12.
J Med Virol ; 91(11): 1970-1978, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31273794

RESUMO

Direct acting antiviral (DAA) therapy against hepatitis C virus (HCV) increases sustained virologic response rates. Nevertheless, drug resistance has occasionally been associated with failure to DAA. However, the information about the prevalence of NS5A and NS5B resistance-associated substitutions (RASs) in Argentina is very scarce. In this study, we determine the prevalence of NS5A and NS5B resistances to treatment in Argentinean DAA treatment-naïve patients chronically infected with genotype 1 (HCV-1). In this retrospective cross-sectional study, 108 HCV-1-infected patients were studied. RASs in NS5A and NS5B were analyzed by Sanger at baseline and phylogenetic analysis was performed. NS5A and NS5B RASs were detected in 25.8% and 6.3% of the analyzed sequences, respectively. The most frequent primary RASs for NS5A were L31M (7.5%) and Y93H (3.2%) and for NS5B was L159F (3.8%). No association between the presence of RASs and the outcome of DAA treatment was found in this study. Additionally, most of the Argentinean samples were randomly distributed among sequences around the world in the phylogenetic analysis. Only one significant Argentinean cluster was observed in both regions but without any particular RASs pattern. Baseline RASs in NS5A and NS5B were frequently observed in HCV-1-infected patients from Buenos Aires, Argentina but not related to treatment outcome. No clusters related to RASs transmission were observed in the phylogenetic analysis. The frequency of RASs detected in this study supports the need for more molecular epidemiology studies on RASs to adjust local treatment guidelines with the incorporation of autochthonous data.


Assuntos
Substituição de Aminoácidos , Antivirais/uso terapêutico , Farmacorresistência Viral/genética , Hepacivirus/genética , Proteínas não Estruturais Virais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Argentina/epidemiologia , Estudos Transversais , Feminino , Genótipo , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , Estudos Retrospectivos
13.
J Viral Hepat ; 26(5): 552-560, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30576055

RESUMO

The massive implementation of the vaccine and antiviral agents against hepatitis B virus (HBV), targeting the envelope and viral polymerase genes, induces a selection pressure that might lead to the emergence of variants that impair the effectiveness of the vaccine, diagnostic methods and antiviral therapy. The aim of this study was to evaluate the prevalence of HBV vaccine escape mutants (VEMs), diagnostic failure mutants (DFMs) and treatment resistance mutants (ARMs) among individuals from Buenos Aires, Argentina. HBV surface antigen and polymerase sequences obtained from serum samples of 530 HBV-infected individuals were analysed. Samples belonged to genotypes A (28.1%), D (13.6%) and F (58.3%). VEMs, DMFs and ARMs were present in 40 (7.5%), 57 (10.7%) and 27 (5.1%) samples within the studied population. Additionally, eight nonpreviously reported VEMs and nine DFMs were identified. VEMs and DFMs were biased by genotype, being higher in genotype D (33.3% and 33.3%) compared to genotype A (6% and 17.4%) and genotype F (2.3% and 2.3%) (P > 0.001). On the contrary, there was no association between the presence of ARMs and HBV genotype (P = 0.324). VEMs, DFMs and ARMs create public health concerns. The current study provided valuable information about mutants in surface antigen and polymerase in HBV-infected patients from Argentina where HBV-F is the most prevalent genotype. Consequently, it constitutes an important reference for Latin American clinicians in order to optimize the management of HBV-infected patients.


Assuntos
Genótipo , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B/epidemiologia , Hepatite B/virologia , Mutação , Adulto , Argentina/epidemiologia , Estudos Transversais , Farmacorresistência Viral , Reações Falso-Negativas , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/imunologia , Humanos , Evasão da Resposta Imune , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Prevalência , Estudos Retrospectivos
14.
Virus Res ; 240: 140-146, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28837817

RESUMO

Incorporation of direct acting antivirals (DAA) in the treatment of Hepatitis C Virus (HCV) significantly increases sustained virologic response rates. However, despite the greater potency offered by these antivirals, drug resistance plays a key role in patients with failure to DAA. Nevertheless, there is no information about the prevalence of resistance-associated substitutions (RASs) in Argentina. The aim of this study was to analyze HCV variants resistant to protease inhibitors (PI) in naïve patients infected with HCV genotype 1 from Argentina. In this retrospective cross-sectional study, 103 patients infected with HCV-1 were included. Eighteen positions related with RASs were analyzed by Sanger at baseline and phylogenetic analysis was performed to determine the diversification of this samples. The analyzed RASs were present in 38 out of 103 patients (36.9%) infected with HCV-1. Patients infected with subtype HCV-1b had higher prevalence of baseline RASs than patients infected with HCV-1a [51.6% vs. 12.8%, respectively (p<0.001)]. The Q80K polymorphism was not found in HCV-1a samples, even when 51% of them belonged to cluster 1, which is associated with a high frequency of Q80K. Phylogenetic analysis showed that Argentinean samples were intermingled with sequences from other geographic regions. RASs to PI were highly prevalent and subtype dependent in treatment-naïve Argentinean patients. Surprisingly, Q80K polymorphism was not detected in our study population. The phylogenetic analysis showed no relationship between our samples and other samples from Brazil which also present a low prevalence of Q80K. This study supports the need for surveillance of resistance in patients who will be treated with DAA in each particular country since the observed RASs have very different prevalence worldwide.


Assuntos
Farmacorresistência Viral , Hepacivirus/genética , Hepatite C/virologia , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/genética , Adulto , Argentina/epidemiologia , Feminino , Genótipo , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepacivirus/enzimologia , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Filogenia , Polimorfismo Genético , Prevalência , Estudos Retrospectivos , Proteínas não Estruturais Virais/metabolismo
15.
PLoS One ; 12(7): e0182193, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28753662

RESUMO

OBJECTIVE: To evaluate the use of hepatitis C virus (HCV) NS3 sequencing as alternative to the comercially available Versant HCV 2.0 reverse hybridization line-probe assay (LiPA 2.0) to determine HCV genotype 1 (HCV-1) subtypes. PATIENTS AND METHODS: A cohort of 104 patients infected by HCV-1 according to LiPA 2.0 was analyzed in a cross-sectional study conducted in patients seen from January 2012 to June 2016 at an outpatient clinic in Buenos Aires, Argentina. RESULTS: The samples were included within well supported subtype clades: 64 with HCV-1b and 39 with HCV-1a infection. Twenty of the HCV-1a infected patientes were included in a supported sub-clade "1" and 19 individuals were among the basal sub-clade "2". LiPA 2.0 failed to subtype HCV-1 in 20 (19.2%) individuals. Subtype classification determined by NS3 direct sequencing showed that 2/18 (11.1%) of the HCV-1a-infected patients as determined by LiPA 2.0 were in fact infected by HCV-1b. Of the HCV-1b-infected according to LiPA 2.0, 10/66 (15.2%) patients showed HCV-1a infection according to NS3 sequencing. Overall misclassification was 14.3% (κ-index for the concordance with NS3 sequencing = 0.635). One (1%) patient was erroneously genotyped as HCV-1 and was revealed as HCV genotype 4 infection. CONCLUSIONS: Genomic sequencing of the HCV NS3 region represents an adequate alternative since it provides reliable genetic information. It even distinguishes between HCV-1a clades related to resistance-associated substitutions to HCV protease inhibitors, it provides reliable genetic information for genotyping/subgenotyping and simultaneously allows to determine the presence of resistance-associated substitutions to currently recommended DAAs.


Assuntos
Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/virologia , Filogenia , Proteínas não Estruturais Virais/genética , Argentina , Estudos Transversais , Genoma Viral/genética , Genótipo
16.
Mol Carcinog ; 56(2): 371-380, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27163636

RESUMO

Chronic Hepatitis C Virus (HCV) infection is a major risk for hepatocellular carcinoma (HCC) development. HCV Core protein has been associated with the modulation of potentially oncogenic cellular processes and E2 protein has been useful in evolutive studies to analyze the diversity of HCV. Thus, the aim of this study was to evaluate HCV compartmentalization in tumoral, non-tumoral liver tissue and serum and to identify viral mutations potentially involved in carcinogenesis. Samples were obtained from four patients with HCC who underwent liver transplantation. Core and E2 were amplified, cloned and sequenced. Phylogenies and BaTS Test were performed to analyze viral compartmentalization and a signature sequence analysis was conducted by VESPA. The likelihood and Bayesian phylogenies showed a wide degree of compartmentalization in the different patients, ranging from total clustering to a more scattered pattern with small groups. Nevertheless, the association test showed compartmentalization for the three compartments and both viral regions tested in all the patients. Signature amino acid pattern supported the compartmentalization in three of the cases for E2 protein and in two of them for Core. Changes observed in Core included polymorphism R70Q/H previously associated with HCC. In conclusion, evidence of HCV compartmentalization in the liver of HCC patients was provided and further biological characterization of these variants may contribute to the understanding of carcinogenesis mediated by HCV infection. © 2016 Wiley Periodicals, Inc.


Assuntos
Carcinoma Hepatocelular/virologia , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Neoplasias Hepáticas/virologia , Fígado/virologia , Mutação , Idoso , Sequência de Aminoácidos , Carcinoma Hepatocelular/sangue , Feminino , Hepatite C/sangue , Hepatite C/virologia , Humanos , Neoplasias Hepáticas/sangue , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Filogenia , Proteínas do Core Viral/química , Proteínas do Core Viral/genética
17.
Ann Hepatol ; 14(4): 442-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26019029

RESUMO

Hepatitis C virus (HCV) has a short replication time, high mutation rates and large population sizes, all of which make it an excellent experimental model for evolution studies, because evolution can be visualized in real-time. In this review, we discuss the implications to study HCV evolution at the interpatient and intrapatient levels of infection. The HCV interpatient dynamics is relatively slow, because the generation time is generally long. Then, at population level, the HCV diversity originated by the high mutation and replication rates is modulated by the bottleneck at transmission. Thus, when the virus is transmitted to other hosts, viral diversity is reduced as a result of the founder effect. On the other hand, during intrapatient infection, HCV evolves rapidly, resulting in quasispecies. Accumulated evidence suggests that this quasispecies composition of the HCV population within the same individual may allow the virus to evade the immune response or escape treatment, leading to chronic infection. Thus, a better understanding of the complexities underlying the molecular evolution of HCV in natural populations is needed before accurate predictions of viral evolution can be made. In summary, HCV evolves both within and among patients. Consequently, HCV evolution should be studied at both levels in order to better understand the natural history of the virus and its potential implications in epidemiology, outcome of infection and progression of liver disease.


Assuntos
Evolução Molecular , Hepacivirus/genética , Hepatite C/virologia , Antivirais/uso terapêutico , Farmacorresistência Viral , Genótipo , Hepacivirus/efeitos dos fármacos , Hepacivirus/crescimento & desenvolvimento , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/imunologia , Hepatite C/transmissão , Humanos , Evasão da Resposta Imune , Mutação , Fenótipo , Fatores de Tempo , Replicação Viral
18.
Rev Argent Microbiol ; 46(3): 218-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25444131

RESUMO

Bacterial richness in maritime Antarctica has been poorly described to date. Phylogenetic affiliation of seawater free-living microbial assemblages was studied from three locations near the Argentinean Jubany Station during two Antarctic summers. Sixty 16S RNA cloned sequences were phylogenetically affiliated to Alphaproteobacteria (30/60 clones), Gammaproteobacteria(19/60 clones), Betaproteobacteria and Cytophaga-Flavobacteriia-Bacteroides (CFB), which were (2/60) and (3/60) respectively. Furthermore, six out of 60 clones could not be classified. Both, Alphaproteobacteria and Gammaproteobacteria, showed several endemic and previously undescribed sequences. Moreover, the absence of Cyanobacteria sequences in our samples is remarkable. In conclusion, we are reporting a rich sequence assemblage composed of widely divergent isolates among themselves and distant from the most closely related sequences currently deposited in data banks.


Assuntos
Bactérias/isolamento & purificação , Água do Mar/microbiologia , Regiões Antárticas , Bactérias/classificação , Bactérias/genética , Sequência de Bases , DNA Bacteriano/genética , DNA Ribossômico/genética , Evolução Molecular , Microbiota , Dados de Sequência Molecular , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Ribotipagem
19.
Rev. argent. microbiol ; 46(3): 218-230, oct. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-734583

RESUMO

.


Bacterial richness in maritime Antarctica has been poorly described to date. Phylogenetic affiliation of seawater free-living microbial assemblages was studied from three locations near the Argentinean Jubany Station during two Antarctic summers. Sixty 16S RNA cloned sequences were phylogenetically affiliated to Alphaproteobacteria (30/60 clones), Gammaproteobacteria(19/60 clones), Betaproteobacteria and Cytophaga-Flavobacteriia- Bacteroides (CFB), which were (2/60) and (3/60) respectively. Furthermore, six out of 60 clones could not be classified. Both, Alphaproteobacteria and Gammaproteobacteria, showed several endemic and previously undescribed sequences. Moreover, the absence of Cyanobacteria sequences in our samples is remarkable. In conclusion, we are reporting a rich sequence assemblage composed of widely divergent isolates among themselves and distant from the most closely related sequences currently deposited in data banks.


Assuntos
Bactérias/isolamento & purificação , Água do Mar/microbiologia , Regiões Antárticas , Sequência de Bases , Bactérias/classificação , Bactérias/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Evolução Molecular , Microbiota , Dados de Sequência Molecular , Filogenia , Ribotipagem , RNA Bacteriano/genética , /genética
20.
J Clin Microbiol ; 52(11): 4027-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25143567

RESUMO

The accuracy of LiPA 2.0 for hepatitis C virus 1 (HCV-1) subtype classification was analyzed. LiPA 2.0 genotype results from 101 HCV-1-infected patients were compared to genotype findings determined by direct core sequencing. Eleven (11%) samples were misclassified. Given the influence of the HCV-1-subtype in the anti-HCV therapy response, an alternative classification method is warranted.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/virologia , Adulto , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , RNA Viral/genética , Análise de Sequência de DNA
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