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1.
J Viral Hepat ; 30(6): 540-543, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36825877

RESUMEN

Hepatitis B virus (HBV) is the main etiological agent of hepatocellular carcinoma (HCC) worldwide. It has been classified into nine genotypes and several subgenotypes, with uneven global distribution. There is growing evidence that the viral genotype influences the course and outcome of chronic hepatitis B infection. Two evolutionarily different clusters of the subgenotype F1b, called basal and cosmopolitan, have been described. The two clusters have constrained geographical distribution, with the particular feature that the basal cluster is present in regions of high HCC incidence, while the Cosmopolitan cluster is found in regions of low HCC incidence. The BCP/pC region was sequenced in 68 cases chronically infected with the F1b subgenotype to determine if there was a differential pattern of pathogenic-associated mutations between both clusters. Twenty-two of the 68 cases belonged to the subgenotype F1b basal cluster and 46 to the cosmopolitan cluster. Among the HBeAg-negative patients the A1762T/G1764A and G1896A mutations were more frequently found in the basal samples (85.7 and 92.9%) compared to the cosmopolitan ones (50 and 18.2%). Interestingly, no HBeAg loss-associated mutations were observed in 7.1 and 36.4% of the basal and cosmopolitan cases, respectively. The different rate of mutations associated with a more severe course of chronic hepatitis in the basal cluster would support the difference in the HCC incidence rate in the geographical regions where the basal cluster is restricted.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B Crónica , Hepatitis B , Neoplasias Hepáticas , Humanos , Virus de la Hepatitis B/genética , Tasa de Mutación , Hepatitis B Crónica/complicaciones , Hepatitis B/complicaciones , Mutación , Genotipo , ADN Viral/genética
2.
J Med Virol ; 95(10): e29195, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37881005

RESUMEN

Hepatitis B e antigen (HBeAg) loss represents a late stage of chronic hepatitis B virus (HBV) infection associated with a drastic decrease in HBV-DNA, a lower risk of disease progression, and the occurrence of several mutations in the preCore/core region. However, the underlying mechanisms supporting the downregulation of viral replication have yet to be elucidated. In the present study, the analysis of the frequency of subgenotype D1 core protein (HBc) mutations associated with HBeAg status revealed a higher mutation rate in HBeAg-negative sequences compared to HBeAg-positive ones. Particularly, 22 amino acids exhibited a higher frequency of mutation in HBeAg-negative sequences, while the remaining residues showed a high degree of conservation. Subsequently, the assessment of HBc mutants derived from HBeAg-negative patients in viral structure and replicative capacity revealed that HBc mutations have the ability to modulate the subcellular localization of the protein (either when the protein was expressed alone or in the context of viral replication), capsid assembly, and, depending on specific mutation patterns, alter covalently closed circular DNA (cccDNA) recycling and up- or downregulate viral replication. In conclusion, HBc mutations associated with HBeAg-negative status impact on various stages of the HBV life cycle modulating viral replication during the HBeAg-negative stage of infection.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Antígenos e de la Hepatitis B/genética , Antígenos e de la Hepatitis B/análisis , Mutación , Replicación Viral , ADN Viral/genética , ADN Viral/análisis
3.
J Virol ; 93(13)2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31019053

RESUMEN

Equine influenza virus (EIV) causes severe acute respiratory disease in horses. Currently, the strains belonging to the H3N8 subtype are divided into two clades, Florida clade 1 (FC1) and Florida clade 2 (FC2), which emerged in 2002. Both FC1 and FC2 clades were reported in Asian and Middle East countries in the last decade. In this study, we described the evolution, epidemiology, and molecular characteristic of the EIV lineages, with focus on those detected in Asia from 2007 to 2017. The full genome phylogeny showed that FC1 and FC2 constituted separate and divergent lineages, without evidence of reassortment between the clades. While FC1 evolved as a single lineage, FC2 showed a divergent event around 2004 giving rise to two well-supported and coexisting sublineages, European and Asian. Furthermore, two different spread patterns of EIV in Asian countries were identified. The FC1 outbreaks were caused by independent introductions of EIV from the Americas, with the Asian isolates genetically similar to the contemporary American lineages. On the other hand, the FC2 strains detected in Asian mainland countries conformed to an autochthonous monophyletic group with a common ancestor dated in 2006 and showed evidence of an endemic circulation in a local host. Characteristic aminoacidic signature patterns were detected in all viral proteins in both Asian-FC1 and FC2 populations. Several changes were located at the top of the HA1 protein, inside or near antigenic sites. Further studies are needed to assess the potential impact of these antigenic changes in vaccination programs.IMPORTANCE The complex and continuous antigenic evolution of equine influenza viruses (EIVs) remains a major hurdle for vaccine development and the design of effective immunization programs. The present study provides a comprehensive analysis showing the EIV evolutionary dynamics, including the spread and circulation within the Asian continent and its relationship to global EIV populations over a 10-year period. Moreover, we provide a better understanding of EIV molecular evolution in Asian countries and its consequences on the antigenicity. The study underscores the association between the global horse movement and the circulation of EIV in this region. Understanding EIV evolution is imperative in order to mitigate the risk of outbreaks affecting the horse industry and to help with the selection of the viral strains to be included in the formulation of future vaccines.


Asunto(s)
Enfermedades de los Caballos/epidemiología , Enfermedades de los Caballos/virología , Subtipo H3N8 del Virus de la Influenza A/clasificación , Subtipo H3N8 del Virus de la Influenza A/aislamiento & purificación , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/virología , Filogenia , Animales , Asia , Brotes de Enfermedades , Evolución Molecular , Caballos , Subtipo H3N8 del Virus de la Influenza A/genética , Subtipo H7N7 del Virus de la Influenza A/clasificación , Filogeografía , Proteínas Virales/genética
4.
J Viral Hepat ; 27(6): 620-630, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32052519

RESUMEN

The genotype F (HBV-F) is an autochthonous Native American strain of the hepatitis B virus. In this study, we reconstruct the HBV-F long-term evolution under a hypothesis of co-divergence with humans in Central and South America, since their entry into the region 14.5-16 thousand years ago. The Bayesian phylogeographic reconstruction supported a virus-host co-expansion; however, two evolutionary scenarios would have been present. Whereas subgenotype F1 spreads along a Pacific coastal route and would have evolved associated with Central American and Andean cultures from the west of the continent, subgenotypes F2-F6 spread along the Atlantic coastline and inner pathways associated with communities inhabiting the tropical forest lowlands. Then, we propose a model for HBV-F evolution in which the selection of differential biological characteristics in these two main groups would be related to their evolution in host populations with different genetic backgrounds and dissimilar demographic conditions.


Asunto(s)
Evolución Molecular , Virus de la Hepatitis B , Hepatitis B , Teorema de Bayes , América Central , Genotipo , Hepatitis B/historia , Virus de la Hepatitis B/genética , Historia Antigua , Humanos , Filogenia , América del Sur
5.
J Viral Hepat ; 26(5): 552-560, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30576055

RESUMEN

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.


Asunto(s)
Genotipo , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/epidemiología , Hepatitis B/virología , Mutación , Adulto , Argentina/epidemiología , Estudios Transversales , Farmacorresistencia Viral , Reacciones Falso Negativas , Femenino , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/inmunología , Humanos , Evasión Inmune , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Prevalencia , Estudios Retrospectivos
6.
Arch Virol ; 164(2): 447-455, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30417200

RESUMEN

Hepatitis B virus (HBV) circulates as a collection of genetically related variants that evolve throughout the chronic infection. Those viral variants that have the greatest fitness are fixed. We recently showed different fitness for HBV variants involved in two epidemiological situations. To understand these fitness differences better, we determined the levels of extracellular HBV DNA, the synthesis of HBV DNA intermediates, and the expression of HBeAg and HBsAg in transfection and cotransfection assays. Our results show that for the subgenotype (sgt) D1, which has an 8-nucleotide deletion (sgtD1del) and exhibits lower fitness, the levels of extracellular DNA and intracellular replicative intermediates were much lower than with sgtD1wt or sgtD1mut (G1896A), which had higher fitness. In addition, in the cotransfection assay, sgtD1del inhibited sgtD1mut but not sgtD1wt replication. We also found that sgtF1b, which exhibits higher fitness, produces significantly higher levels of both extracellular DNA and intracellular replicative intermediates than does the lower-fitness sgtF4. These results demonstrate a relationship between fitness and the replicative ability of the HBV genome in the transfection assay. In addition, the data obtained by cotransfecting cells with sgtD1del and sgtD1mut provide new information about the impact of simultaneous replication of two viral variants in the same cell system on HBV replication.


Asunto(s)
Coinfección/virología , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/fisiología , Hepatitis B/virología , Genotipo , Antígenos de Superficie de la Hepatitis B/genética , Antígenos e de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Humanos , Transfección , Replicación Viral
7.
Mol Carcinog ; 56(2): 371-380, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27163636

RESUMEN

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.


Asunto(s)
Carcinoma Hepatocelular/virología , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C/complicaciones , Neoplasias Hepáticas/virología , Hígado/virología , Mutación , Anciano , Secuencia de Aminoácidos , Carcinoma Hepatocelular/sangre , Femenino , Hepatitis C/sangre , Hepatitis C/virología , Humanos , Neoplasias Hepáticas/sangre , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Filogenia , Proteínas del Núcleo Viral/química , Proteínas del Núcleo Viral/genética
8.
Arch Virol ; 160(4): 909-15, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25762309

RESUMEN

The aim of this study was to analyze the prevalence of hepatitis C virus (HCV) genotypes in Córdoba province, Argentina, over a 12-year period and to study the changes at the molecular level. The HCV genotype was determined in 357 HCV-infected patients, and the phylogeny and demographic reconstruction for HCV-1 was assessed. A significant reduction in HCV-2 prevalence with respect to HCV-1 in Córdoba after 2003 was observed. These findings are consistent with the epidemiological changes observed in South America. Nevertheless, the consequences of these changes remain to be elucidated.


Asunto(s)
Hepacivirus/genética , Hepatitis C/virología , Argentina/epidemiología , Genotipo , Hepacivirus/clasificación , Hepacivirus/aislamiento & purificación , Hepatitis C/epidemiología , Humanos , Filogenia , América del Sur/epidemiología
9.
Ann Hepatol ; 14(4): 442-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26019029

RESUMEN

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.


Asunto(s)
Evolución Molecular , Hepacivirus/genética , Hepatitis C/virología , Antivirales/uso terapéutico , Farmacorresistencia Viral , Genotipo , Hepacivirus/efectos de los fármacos , Hepacivirus/crecimiento & desarrollo , Hepacivirus/inmunología , Hepacivirus/patogenicidad , Hepatitis C/diagnóstico , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Hepatitis C/inmunología , Hepatitis C/transmisión , Humanos , Evasión Inmune , Mutación , Fenotipo , Factores de Tiempo , Replicación Viral
10.
BMC Infect Dis ; 14: 218, 2014 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-24755089

RESUMEN

BACKGROUND: Transfusion-transmitted infections are a major problem associated with blood transfusion. The aim of this study was to determine prevalence and trends of HBV, HCV and HIV in blood donors in Argentina. METHODS: A retrospective study was carried out in blood donors of 27 transfusion centers covering the whole country over a period of eight years (2004-2011). Serologic screening assays for HBsAg, anti-HBc, anti-HCV, and anti-HIV were performed in all centers and nucleic acid amplification testing (NAT) was performed in 2 out of the 27 centers. RESULTS: The 2,595,852 samples tested nationwide from 2004 to 2011 showed that the prevalence of HBsAg decreased from 0.336% to 0.198% (p < 0.0001), that of anti-HBc from 2.391% to 2.007% (p < 0.0001), that of anti-HCV from 0.721% to 0.460%, (p < 0.0001) and that of anti-HIV from 0.208% to 0.200 (p = 0.075). The prevalence of HBV, HCV and HIV was unevenly distributed among the different regions of the country. Two out of 74,838 screening- negative samples were positive in NAT assays (1 HIV-RNA and 1 HCV-RNA); moreover, HBV-DNA, HCV-RNA and HIV-RNA were detected in 60.29, 24.54 and 66.67% of screening-positive samples of the corresponding assays. As regards donors age, positive HBV-DNA and HCV-RNA donors were significantly older than healthy donors (46.6, 50.5 and 39.5 y respectively, p < 0.001). CONCLUSIONS: Argentina has a low prevalence of HBsAg, anti-HCV and anti-HIV in blood donors, with a decreasing trend for HBsAg, anti-HBc and anti-HCV but not for anti-HIV over the last 8 years. The uneven distribution of transfusion-transmitted infections prevalence among the different regions of the country highlights the need to implement regional awareness campaigns and prevention. The discrepancy between samples testing positive for screening assays and negative for NAT assays highlights the problem of blood donors who test repeatedly reactive in screening assays but are not confirmed as positive upon further testing. The uneven distribution of age between healthy donors and NAT-positive donors could be related to changes in risks of these pathogens in the general population and might be attributed to a longer exposure to transmission risk factors in elderly people.


Asunto(s)
Donantes de Sangre/estadística & datos numéricos , Infecciones por VIH/epidemiología , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Adulto , Anticuerpos Antivirales/sangre , Argentina/epidemiología , Femenino , VIH/inmunología , Hepacivirus/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos
11.
Virol J ; 10: 245, 2013 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-23890410

RESUMEN

BACKGROUND: Due to the high prevalence of viral infections having no specific treatment and the constant appearance of resistant viral strains, the development of novel antiviral agents is essential. The aim of this study was to evaluate the antiviral activity against bovine viral diarrhea virus, herpes simplex virus type 1 (HSV-1), poliovirus type 2 (PV-2) and vesicular stomatitis virus of organic (OE) and aqueous extracts (AE) from: Baccharis gaudichaudiana, B. spicata, Bidens subalternans, Pluchea sagittalis, Tagetes minuta and Tessaria absinthioides. A characterization of the antiviral activity of B. gaudichaudiana OE and AE and the bioassay-guided fractionation of the former and isolation of one active compound is also reported. METHODS: The antiviral activity of the OE and AE of the selected plants was evaluated by reduction of the viral cytopathic effect. Active extracts were then assessed by plaque reduction assays. The antiviral activity of the most active extracts was characterized by evaluating their effect on the pretreatment, the virucidal activity and the effect on the adsorption or post-adsorption period of the viral cycle. The bioassay-guided fractionation of B. gaudichaudiana OE was carried out by column chromatography followed by semipreparative high performance liquid chromatography fractionation of the most active fraction and isolation of an active compound. The antiviral activity of this compound was also evaluated by plaque assay. RESULTS: B. gaudichaudiana and B. spicata OE were active against PV-2 and VSV. T. absinthioides OE was only active against PV-2. The corresponding three AE were active against HSV-1. B. gaudichaudiana extracts (OE and AE) were the most selective ones with selectivity index (SI) values of 10.9 (PV-2) and > 117 (HSV-1). For this reason, both extracts of B. gaudichaudiana were selected to characterize their antiviral effects. Further bioassay-guided fractionation of B. gaudichaudiana OE led to an active fraction, FC (EC50 = 3.1 µg/ml; SI = 37.9), which showed antiviral activity during the first 4 h of the viral replication cycle of PV-2 and from which the flavonoid apigenin (EC50 = 12.2 ± 3.3 µM) was isolated as a major compound. CONCLUSIONS: The results showed that, among the species studied, B. gaudichaudiana seemed to be the most promising species as a source of antiviral agents.


Asunto(s)
Antivirales/farmacología , Asteraceae/química , Virus ADN/efectos de los fármacos , Extractos Vegetales/farmacología , Plantas Medicinales/química , Virus ARN/efectos de los fármacos , Antivirales/aislamiento & purificación , Cromatografía Liquida , Efecto Citopatogénico Viral/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación , Ensayo de Placa Viral
12.
Virology ; 585: 100-108, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37327595

RESUMEN

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.


Asunto(s)
Virus JC , Humanos , Virus JC/genética , Evolución Biológica , Dinámica Poblacional , Migración Humana , Américas/epidemiología , ADN Viral/genética
13.
J Virol ; 85(11): 5436-45, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21430053

RESUMEN

In the present work, we described the activity of the thiosemicarbazone derived from 5,6-dimethoxy-1-indanone (TSC), which we previously characterized as a new compound that inhibits bovine viral diarrhea virus (BVDV) infection. We showed that TSC acts at a point of time that coincides with the onset of viral RNA synthesis and that it inhibits the activity of BVDV replication complexes (RCs). Moreover, we have selected five BVDV mutants that turned out to be highly resistant to TSC but still susceptible to ribavirin (RBV). Four of these resistant mutants carried an N264D mutation in the viral RNA-dependent RNA polymerase (RdRp). The remaining mutant showed an A392E mutation within the same protein. Some of these mutants replicated slower than the wild-type (wt) virus in the absence of TSC, whereas others showed a partial reversion to the wt phenotype over several passages in the absence of the compound. The docking of TSC in the crystal structure of the BVDV RdRp revealed a close contact between the indane ring of the compound and several residues within the fingers domain of the enzyme, some hydrophobic contacts, and hydrogen bonds with the thiosemicarbazone group. Finally, in the mutated RdRp from resistant BVDV, these interactions with TSC could not be achieved. Interestingly, TSC inhibited BVDV replication in cell culture synergistically with RBV. In conclusion, TSC emerges as a new nonnucleoside inhibitor of BVDV RdRp that is synergistic with RBV, a feature that turns it into a potential compound to be evaluated against hepatitis C virus (HCV).


Asunto(s)
Antivirales/farmacología , Virus de la Diarrea Viral Bovina/efectos de los fármacos , Indanos/farmacología , ARN Viral/biosíntesis , Tiosemicarbazonas/farmacología , Replicación Viral/efectos de los fármacos , Sustitución de Aminoácidos , Animales , Antivirales/química , Línea Celular , Virus de la Diarrea Viral Bovina/fisiología , Farmacorresistencia Viral , Humanos , Indanos/química , Modelos Moleculares , Mutación Missense , Estructura Terciaria de Proteína , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Ribavirina/farmacología , Tiosemicarbazonas/química , Proteínas Virales/genética , Proteínas Virales/metabolismo
14.
Virol J ; 9: 131, 2012 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-22769058

RESUMEN

BACKGROUND: HBV-X protein is associated with the pathogenesis of HBV related diseases, specially in hepatocellular carcinomas of chronic patients. Genetic variability of the X gene includes genotypic specific variations and mutations emerging during chronic infection. Its coding sequence overlaps important regions for virus replication, including the basal core promoter. Differences in the X gene may have implications in biological functions of the protein and thus, affect the evolution of the disease. There are controversial results about the consequences of mutations in this region and their relationship with pathogenesis. The purpose of this work was to describe the diversity of HBV-X gene in chronic hepatitis patients infected with different genotypes, according to liver disease. METHODS: HBV-X gene was sequenced from chronic hepatitis B patient samples, analyzed by phylogeny and genotyped. Nucleotide and aminoacid diversity was determined calculating intragenetic distances. Mutations at 127, 130 and 131 aminoacids were considered in relation to liver disease. RESULTS: The most prevalent genotype detected in this cohort was F (F1 and F4), followed by D and A. Most of the samples corresponding to genotypes A and F1 were HBeAg(+) and for genotypes D and F4, HBeAg(-) samples were represented in a higher percentage. Intragenetic distance values were higher in HBeAg(-) than in positive samples for all genotypes, and lower in overlapped regions, compared to single codification ones. Nucleotide and aminoacid diversities were higher in HBeAg(-), than in HBeAg(+) samples. CONCLUSIONS: Independently of the infecting genotypes, mutations at any of 127, 130 and/or 131 aminoacid positions and HBeAg(-) status were associated with mild liver disease in this cohort.


Asunto(s)
Variación Genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Transactivadores/genética , Sustitución de Aminoácidos , ADN Viral/química , ADN Viral/genética , Genotipo , Hepatitis B Crónica/patología , Humanos , Datos de Secuencia Molecular , Mutación Missense , Filogenia , Análisis de Secuencia de ADN , Proteínas Reguladoras y Accesorias Virales
15.
Bioorg Med Chem ; 20(19): 5986-91, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-22944333

RESUMEN

New chiral purinyl and 8-azapurinyl carbanucleoside derivatives based on indanol were synthesized from commercial available (1S,2S)-trans-1-amino-2-indanol and (1R,2R)-trans-1-amino-2-indanol using a linear methodology. The antiviral activity and cytotoxicity of these compounds were evaluated against herpes simplex virus type 1 (HSV-1) in Vero cells, bovine viral diarrhea virus (BVDV) in Mardin-Darby bovine kidney (MDBK) cells and hepatitis B virus (HBV) in HepG2 2.2.15 cell line. Three compounds, showed an inhibition of the HBsAg levels similar to reference drug lamivudine. One chloropurinyl nucleoside, derived from the cis-1-amino-2-indanol, was cytotoxic on MDBK cells and it could be a lead for developing anticancer agents.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Indanos/química , Indanos/farmacología , Nucleósidos/química , Nucleósidos/farmacología , Animales , Antivirales/síntesis química , Diarrea Mucosa Bovina Viral/tratamiento farmacológico , Bovinos , Línea Celular , Chlorocebus aethiops , Virus de la Diarrea Viral Bovina/efectos de los fármacos , Perros , Células Hep G2 , Hepatitis B/tratamiento farmacológico , Virus de la Hepatitis B/efectos de los fármacos , Herpes Simple/tratamiento farmacológico , Herpesvirus Humano 1/efectos de los fármacos , Humanos , Indanos/síntesis química , Nucleósidos/síntesis química , Estereoisomerismo , Células Vero
16.
Front Microbiol ; 13: 946703, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35966715

RESUMEN

Hepatitis B virus (HBV) subgenotype F1b infection has been associated with the early occurrence of hepatocellular carcinoma in chronically infected patients from Alaska and Peru. In Argentina, however, despite the high prevalence of subgenotype F1b infection, this relationship has not been described. To unravel the observed differences in the progression of the infection, an in-depth molecular and biological characterization of the subgenotype F1b was performed. Phylogenetic analysis of subgenotype F1b full-length genomes revealed the existence of two highly supported clusters. One of the clusters, designated as gtF1b Basal included sequences mostly from Alaska, Peru and Chile, while the other, called gtF1b Cosmopolitan, contained samples mainly from Argentina and Chile. The clusters were characterized by a differential signature pattern of eight nucleotides distributed throughout the genome. In vitro characterization of representative clones from each cluster revealed major differences in viral RNA levels, virion secretion, antigen expression levels, as well as in the localization of the antigens. Interestingly, a differential regulation in the expression of genes associated with tumorigenesis was also identified. In conclusion, this study provides new insights into the molecular and biological characteristics of the subgenotype F1b clusters and contributes to unravel the different clinical outcomes of subgenotype F1b chronic infections.

17.
Trans R Soc Trop Med Hyg ; 116(1): 34-42, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33739412

RESUMEN

BACKGROUND: Few studies about the evolutionary history of the hepatitis E virus (HEV) have been conducted. The aim of our work was to investigate and make inferences about the origin and routes of dispersion of HEV-3 in Argentina. METHODS: Phylogenetic, coalescent and phylogeographic analyses were performed using a 322-bp ORF2 genomic fragment of all HEV-3 sequences with known date and place of isolation published at GenBank until May 2018 (n=926), including 16 Argentinian sequences (isolated from pigs, water and humans). RESULTS: Phylogenetic analysis revealed two clades within HEV-3: abchij and efg. All Argentinian samples were grouped intermingled within clade 3abchij. The coalescent analysis showed that the most recent common ancestor for the clade 3abchij would have existed around the year 1967 (95% highest posterior density (HPD): 1963-1970). The estimated substitution rate was 1.01×10-2 (95%HPD: 9.3×10-3-1.09×10-2) substitutions/site/y, comparable with the rate previously described. The phylogeographic approach revealed a correspondence between phylogeny and place of origin for Argentinian samples, suggesting many HEV introductions in the country, probably from Europe and Japan. CONCLUSIONS: This is the first evolutionary inference of HEV-3 that includes Argentinian strains, showing the circulation of many HEV-3 subtypes, obtained from different sources and places, with recent diversification processes. ACCESSION NUMBERS: [KX812460], [KX812461], [KX812462], [KX812465], [KX812466], [KX812467], [KX812468], [KX812469].


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Animales , Argentina/epidemiología , Genotipo , Hepatitis E/epidemiología , Humanos , Filogenia , Filogeografía , Porcinos
18.
Mol Phylogenet Evol ; 59(1): 114-22, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21296172

RESUMEN

Hepatitis B virus (HBV) is a globally distributed human pathogen. The aim of this work was to analyze the evolutionary history of HBV genotype F, emphasizing on the study of subgenotypes prevalent in the Southern area of South America. Complete genomes of HBV genotype F from 36 samples from Argentina and Chile were sequenced and analyzed by phylogenetic and Bayesian coalescent methods along with sequences obtained from GenBank database. The phylogeography separated not only Central American from South American isolates but also revealed that different subgenotypes are distributed in constrained although not exclusive areas of the continent. The result obtained with time-stamped complete genomes failed to explain the wide geographical distribution and the clustering observed in this genotype. Conversely, the use of Bayesian coalescent analyses with substitution rates as priors, instead of the co-estimation of tMRCA and substitution rate, allowed us to propose a far origin for the HBV genotype F based on the phylogeographical and epidemiological data.


Asunto(s)
Evolución Biológica , Virus de la Hepatitis B/genética , Hepatitis B/sangre , Argentina , Teorema de Bayes , Chile , Especiación Genética , Genotipo , Hepatitis B/epidemiología , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Filogenia , Filogeografía , Recombinación Genética , Alineación de Secuencia , Análisis de Secuencia de ADN
19.
BMC Psychiatry ; 11: 59, 2011 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-21489298

RESUMEN

BACKGROUND: Bipolar Disorder (BD) is a chronic, recurrent and highly prevalent illness. Despite the need for correct diagnosis to allow proper treatment, studies have shown that reaching a diagnosis can take up to ten years due to the lack of recognition of the broader presentations of BD. Frequent comorbidities with other psychiatric disorders are a major cause of misdiagnosis and warrant thorough evaluation. METHODS/DESIGN: ESPECTRA (Occurrence of Bipolar Spectrum Disorders in Eating Disorder Patients) is a single-site cross-sectional study involving a comparison group, designed to evaluate the prevalence of bipolar spectrum in an eating disorder sample. Women aged 18-45 years will be evaluated using the SCID-P and Zurich criteria for diagnosis and the HAM-D, YOUNG, SCI-MOODS, HCL-32, BIS-11, BSQ, WHOQoL and EAS instruments for rating symptoms and measuring clinical correlates. DISCUSSION: The classificatory systems in psychiatry are based on categorical models that have been criticized for simplifying the diagnosis and leading to an increase in comorbidities. Some dimensional approaches have been proposed aimed at improving the validity and reliability of psychiatric disorder assessments, especially in conditions with high rates of comorbidity such as BD and Eating Disorder (ED). The Bipolar Spectrum (BS) remains under-recognized in clinical practice and its definition is not well established in current diagnostic guidelines. Broader evaluation of psychiatric disorders combining categorical and dimensional views could contribute to a more realistic understanding of comorbidities and help toward establishing a prognosis.


Asunto(s)
Trastorno Bipolar/diagnóstico , Trastorno Bipolar/epidemiología , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Adolescente , Adulto , Trastorno Bipolar/clasificación , Brasil/epidemiología , Protocolos Clínicos , Comorbilidad , Estudios Transversales , Errores Diagnósticos , Trastornos de Alimentación y de la Ingestión de Alimentos/clasificación , Femenino , Humanos , Persona de Mediana Edad , Prevalencia , Pronóstico , Psicometría/estadística & datos numéricos
20.
Rev Argent Microbiol ; 43(4): 263-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22274823

RESUMEN

The objective of this study was to determine the prevalence of HPV infection and cervical lesions present in women who attended a health center in a low-resource area of the city of Posadas, Misiones, Argentina. Cervical cell samples (n = 163) were processed for Papanicolaou cytology and HPV-PCR tests. Socio-cultural risk factors were estimated using the odds ratio (OR, CI 95 %). Cervical lesions were detected in 14.7 % of women. The general prevalence of HPV infection was of 38 %. The most common types among the total population were HPV-16 (9.8 %) and HPV-33 (9.3 %). HPV-16 was detected in association with 29.2 % and 6.5 % of women with and without cervical lesions, respectively, the OR being 5.3 (1.8-15.8). Risk factors for HPV-16 infection were a smoking habit and a history of previous sexually-transmitted diseases. These data are important for the implementation of prevention programs, including an appropriate introduction of vaccination and the baseline for virological surveillance in the vaccine era.


Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Prueba de Papanicolaou , Infecciones por Papillomavirus/epidemiología , Pobreza , Cervicitis Uterina/epidemiología , Frotis Vaginal , Adolescente , Adulto , Anciano , Alphapapillomavirus/genética , Argentina , Sondas de ADN de HPV , Femenino , Papillomavirus Humano 16/aislamiento & purificación , Humanos , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Conducta Sexual , Enfermedades de Transmisión Sexual/epidemiología , Fumar/epidemiología , Población Urbana , Cervicitis Uterina/virología , Adulto Joven
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