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1.
Virus Res ; 277: 197840, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31846615

RESUMO

AIM: To assess the association of viral and host genetic variability with the outcome of acute infection with hepatitis B virus subgenotype F1b (HBV/F1b). METHODS: The cohort consisted of 26 patients with acute HBV/F1b infection who exhibit different outcomes: spontaneous resolution (n = 10), progression to chronic hepatitis (n = 10) and acute liver failure (n = 6). HLA SNPs (rs3077, rs9277542, rs2856718 and rs7453920) were determined. The S gene and core promoter/precore/core region were direct sequenced, and this latter region was also ultra-deep sequenced. Mean number of mutations, mutation rate, Shannon entropy, positive selection sites and mutational patterns of quasispecies were compared between groups. RESULTS: HLA SNPs were associated with spontaneous resolution or progression to chronic hepatitis, but not with the development of acute liver failure. The mean number of mutations in the S gene was similar among the three groups. Patients with spontaneous resolution had the lowest number of mutations, mutation rates and Shannon entropy values in the precore/core compared to the other two groups. Ten positive selection sites mapped on HLA-restricted epitopes were related to progression to chronic hepatitis and acute liver failure. Mutations T1753C, A1762T, G1764A, C1766T, T1768A G1896A, G2092T and T2107C were associated with acute liver failure and progression to chronic hepatitis. CONCLUSION: Highly heterogeneous and complex HBV precore/core carrying specific point mutations, combined with the host HLA background, were associated with a worse clinical outcome of acute HBV/F1b infection.


Assuntos
Variação Genética , Antígenos HLA/genética , Vírus da Hepatite B/genética , Hepatite B/genética , Hepatite B/virologia , Mutação Puntual , Doença Aguda , Idoso , Feminino , Genótipo , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Quase-Espécies/genética
2.
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
3.
Arch Bronconeumol ; 51(11): 539-43, 2015 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25800328

RESUMO

INTRODUCTION: Alpha-1 antitrypsin deficiency (AATD) is a genetic disorder associated with early onset chronic obstructive pulmonary disease (COPD) and liver disease. It is also a highly under-diagnosed condition. As early diagnosis could prompt specific interventions such as smoking cessation, testing of family members, genetic counselling and use of replacement therapy, screening programs are needed to identify affected patients. OBJECTIVE: To estimate the prevalence of severe AATD in COPD patients by routine dried blood spot testing and subsequent genotyping in patients with alpha-1 antitrypsin (AAT) levels below an established threshold. MATERIALS AND METHODS: Cross-sectional study of adult COPD patients attending the Hospital Dr. Antonio Cetrángolo (Buenos Aires, Argentina) between 2009 and 2012. The study consisted of capillary blood collection via finger stick to determine AAT levels, clinical evaluation and lung function tests. Genotype was determined in AAT-deficient patients. RESULTS: A total of 1,002 patients were evaluated, of whom 785 (78.34%) had normal AAT levels, while low AAT levels were found in 217 (21.66%). Subsequent genotyping of the latter sub-group found: 15 (1.5%, 95% CI 0.75-2.25) patients with a genotype associated with severe AATD, of whom 12 were ZZ (1.2%, 95% CI 0.52-1.87) and 3 SZ (0.3%, 95% CI 0-0.64). The remaining 202 patients were classified as: 29 Z heterozygotes (2.89%, 95% CI 1.86-3.93), 25 S heterozygotes (2.5%, 95% CI 1.53-3.46) and 4 SS (0.4%, 95% CI 0.01-0.79). A definitive diagnosis could not be reached in 144 patients (14.37%, 95% CI 12.2-16.54). CONCLUSION: The strategy using an initial serum AAT level obtained by dried blood spot testing and subsequent genotyping was a satisfactory initial approach to a screening program for severe AAT, as a definitive diagnosis was achieved in 87% of patients. However, results were not obtained for logistical reasons in the remaining 13%. This major obstacle may be overcome by the use of dried blood spot phenotyping techniques. We believe this approach for detecting AATD in COPD patients, in compliance with national and international guidelines, is supported by our results.


Assuntos
Doença Pulmonar Obstrutiva Crônica/epidemiologia , Deficiência de alfa 1-Antitripsina/epidemiologia , Adulto , Idoso , Algoritmos , Argentina/epidemiologia , Comorbidade , Estudos Transversais , Feminino , Genótipo , Humanos , Focalização Isoelétrica , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Nefelometria e Turbidimetria , Fenótipo , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Fumar/epidemiologia , Espirometria , alfa 1-Antitripsina/sangue , Deficiência de alfa 1-Antitripsina/diagnóstico , Deficiência de alfa 1-Antitripsina/genética
4.
BMC Infect Dis ; 14: 218, 2014 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24755089

RESUMO

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.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Adulto , Anticorpos Antivirais/sangue , Argentina/epidemiologia , Feminino , HIV/imunologia , Hepacivirus/imunologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
7.
Int J Infect Dis ; 15(5): e314-20, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21367634

RESUMO

BACKGROUND: The study of hepatitis B virus (HBV) genomic heterogeneity has become a major issue in investigations aimed at understanding the relationship between HBV mutants and the wide spectrum of clinical and pathological conditions associated with HBV infection. Although most chronically infected HBV patients are inactive carriers, several virological aspects of this state remain unclear. METHODS: In order to determine the prevalence and clinical significance of mutations in the basal core promoter (BCP) and precore (pC) regions among inactive carriers, the nucleotide sequences from 41 inactive carriers were analyzed and compared with those from 29 individuals with chronic active hepatitis. RESULTS: Genotypes A (24.3%), D (37.1%), F1b (12.9%), and F4 (18.6%) were the most prevalent. Mutations in the BCP/pC regions were observed in most of the inactive carriers (92.7%) and in most of the patients with chronic active hepatitis (93.1%). The prevalence of mutation 1764(A) was significantly higher in patients with chronic active hepatitis (65.5%) than in inactive carriers (36.6%) (p=0.038), whereas the prevalences of mutations at the other positions analyzed were not significantly different. Older patients (>50 years) showed BCP/pC patterns with a higher number of substitutions. Mutations were found to be biased by genotype: the 1896(A) mutation was highly prevalent in genotypes D and F4, while alternative substitutions in the pC region were more prevalent in genotypes A and F1b. CONCLUSIONS: Mutations in the BCP/pC regions are the hallmark of chronic anti-HBe-positive individuals; nevertheless, the even distribution of mutations in active and inactive carriers suggests that BCP/pC mutations may occur during HBV infection not strictly related to the HBV infection activity.


Assuntos
Portador Sadio/virologia , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Regiões Promotoras Genéticas/genética , Adulto , Idoso , Sequência de Bases , Portador Sadio/epidemiologia , DNA Viral/sangue , DNA Viral/isolamento & purificação , Feminino , Seguimentos , Genótipo , Anticorpos Anti-Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Estatística como Assunto
10.
Actual. SIDA ; 17(64): 66-69, jun. 2009. ilus
Artigo em Espanhol | LILACS | ID: lil-521996

RESUMO

La anemia es relativamente frecuente en pacientes con infección avanzada por VIH. La aplasia pura de la serie roja (APSR) asociada a la infección por Parvovirus B19 (PVB19) se caracteriza por la ausencia de precursores eritroides en la médula ósea que produce anemia grave normocítica, normocrómica, con un bajo recuento de reticulocitos. Este artículo describe un paciente con infección por VIH con inmunosupresión grave y en fracaso virológico que desarrolló APSR asociada a PV B19.


Severe anemia is quite frequently seen in HIV infected patient with advanced disease. Pure red cell aplasia associated to Parvovirus B19 (PVB 19) infection is characterized by the absence of erythroid precursors in the bone marrow resulting in severe normocytic-normochromic anemia with a low reticulocyte count. This article reports a patient with advanced HIV and virological failure, who developed pure red cell aplasia associated to PVB19.


Assuntos
Humanos , Masculino , Adulto , Aplasia Pura de Série Vermelha/patologia , HIV , Terapia de Imunossupressão , /imunologia , Reticulocitose
12.
Medicina (B Aires) ; 65(4): 333-7, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16193712

RESUMO

A previously healthy 9 year old girl developed nephrotic syndrome with hypertension, microhematuria and normal renal function. The patient evolved as steroid resistant nephrotic syndrome whose initial renal biopsy was consistent with diffuse proliferative mesangial glomerulonephritis with focal segmental glomerulosclerosis. At the time of cyclophosphamide and prednisone treatment, she developed a prolonged febrile syndrome. She also had severe anemia following an aplastic crisis induced by human parvovirus B19 infection and acute renal failure secondary to a severe tubulointersticial disease. Bone marrow and renal tissue, tested by polimerase chain reaction were positive for parvovirus, while the patient's blood was negative. The renal involvement did not improve requiring chronic dialysis support. We believe that the initial glomerular disease could have been due to a parvovirus infection followed by un unexpected acute tubular interstitial nephritis, rapidly progressing to chronic renal disease. This case represents, to our knowledge, the first time that a direct relationship between parvovirus infection and acute tubulointerstitial disease has been demonstrated.


Assuntos
Glomerulonefrite/patologia , Rim/patologia , Nefrite Intersticial/patologia , Infecções por Parvoviridae/patologia , Parvovirus B19 Humano , Biópsia , Criança , Doença Crônica , Feminino , Glomerulonefrite/virologia , Humanos , Falência Renal Crônica/patologia , Falência Renal Crônica/virologia , Nefrite Intersticial/virologia , Infecções por Parvoviridae/complicações , Reação em Cadeia da Polimerase
13.
Medicina (B.Aires) ; 47(4): 367-70, 1987. tab
Artigo em Inglês | LILACS | ID: lil-48536

RESUMO

Se estudiaron, entre junio de 1984 y marzo de 1987, 237 pacientes con hemofilia hallándose una prevalencia de anticuerpos para el virus de la inmunodeficiencia humana (HIV) del 54%. De ellos, 188 enfermos hemofílicos (156 hemofilia A y 22 hemofilia B) pudieron ser estudiados en detalle; el 54% de los receptores de factor VIII y el 59% de los de factor IX presentaron anticuerpos para HIV; en ambos grupos, la seropositividad estaba asociada a la severidad de la hemofilia. Se observó, además, que 89 de 102 (87%) pacientes hemofílicos sintomáticos presentaron anticuerpos para HIV, comparado con 9 de 26 (12%) pacientes asintomáticos. Se estudiaron 12 mujeres con contactos sexuales con pacientes hemofílicos seropositivos para HIV; en 3 (25%) de ellas se hallaron anticuerpos para el virus y una de ellas presenta linfoadenopatía y pérdida de peso. Nuestros resultados permiten inferir que un alto porcentaje de los hemofílicos estudiados, tratados con Factor VIII y Factor IX antes de 1985, presentan anticuerpos para el virus y que esta seropositividad está asociada a sintomatología y al número de transfusiones recibidas


Assuntos
Humanos , Masculino , Feminino , Anticorpos Antivirais/análise , Hemofilia A/imunologia , HIV/imunologia , Argentina , Hemofilia B/imunologia , Técnicas Imunológicas
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