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1.
J Formos Med Assoc ; 119(3): 752-756, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31477484

RESUMEN

Continuous strengthening of the safety of blood products to reduce the risk of transfusion-transmitted HCV in recipients is an important issue of Taiwanese government concern. Since 2013, highly sensitivity serology and NAT assays were simultaneously used for blood donation screening to shorten the window period of HIV, HBV and HCV infections. 15 cases of suspected transfusion-transmitted HCV infection were analyzed in 2015-2018. No HCV nucleic acid was detected among a total 91 bags of donated blood. Eleven cases among the 15 suspected recipients were positive for HCV nucleic acid, and 9 recipients had genotype results. Of these 9 recipients, five for genotype 1b (5/9, 55.6%), three for genotype 2a (3/9, 33.3%) and one for genotype 2b (1/9, 11.1%). We will continuously monitor the blood safety of recipients. There have been no confirmed cases of acute hepatitis C (AHC) infection due to transfusions of HCV contaminated blood product in 2015-2018 in Taiwan.


Asunto(s)
Hepatitis C/transmisión , Hepatovirus/aislamiento & purificación , Seguridad del Paciente , Reacción a la Transfusión , Hepatovirus/genética , Humanos , Tamizaje Masivo , Técnicas de Amplificación de Ácido Nucleico , Pruebas Serológicas/métodos , Taiwán
3.
mBio ; 6(4)2015 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-26307166

RESUMEN

UNLABELLED: Describing the viral diversity of wildlife can provide interesting and useful insights into the natural history of established human pathogens. In this study, we describe a previously unknown picornavirus in harbor seals (tentatively named phopivirus) that is related to human hepatitis A virus (HAV). We show that phopivirus shares several genetic and phenotypic characteristics with HAV, including phylogenetic relatedness across the genome, a specific and seemingly quiescent tropism for hepatocytes, structural conservation in a key functional region of the type III internal ribosomal entry site (IRES), and a codon usage bias consistent with that of HAV. IMPORTANCE: Hepatitis A virus (HAV) is an important viral hepatitis in humans because of the substantial number of cases each year in regions with low socioeconomic status. The origin of HAV is unknown, and no nonprimate HAV-like viruses have been described. Here, we describe the discovery of an HAV-like virus in seals. This finding suggests that the diversity and evolutionary history of these viruses might be far greater than previously thought and may provide insight into the origin and pathogenicity of HAV.


Asunto(s)
Hepatovirus/genética , Hepatovirus/aislamiento & purificación , Filogenia , Phocidae/virología , Animales , Codón , Genoma Viral , Genotipo , Virus de la Hepatitis A Humana/genética , Hepatovirus/fisiología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hígado/virología , Pulmón/virología , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Bazo/virología , Replicación Viral
4.
Euro Surveill ; 19(50): 20992, 2014 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25597541

RESUMEN

In October 2012, a hepatitis A (HA) outbreak with 83 laboratory-confirmed cases occurred in Lower Saxony. We defined primary outbreak cases as people with laboratory-confirmed HA and symptom onset between 8 October and 12 November 2012, residing in or visiting the affected districts. Secondary outbreak cases were persons with symptom onset after 12 November 2012 and close contact with primary cases. We identified 77 primary and six secondary cases. We enrolled 50 primary cases and 52 controls matched for age and sex, and found that 82% of cases and 60% of controls had consumed products from a particular bakery (OR=3.09; 95% CI: 1.15­8.68). Cases were more likely to have eaten sweet pastries (OR=5.74; 95% CI: 1.46­22.42). Viral isolates from five selected cases and three positively tested surfaces in the bakery had identical nucleotide sequences. One additional identical isolate derived from a salesperson of the bakery suffering from a chronic disease that required immunosuppressive treatment. Epidemiological and laboratory findings suggested that the salesperson contaminated products while packing and selling. Future risk assessment should determine whether food handlers with chronic diseases under immunosuppressive treatment could be more at risk of contaminating food and might benefit from HAV immunisation.


Asunto(s)
Brotes de Enfermedades , Contaminación de Alimentos/estadística & datos numéricos , Hepatitis A/epidemiología , Hepatovirus/genética , Hepatovirus/aislamiento & purificación , Adolescente , Adulto , Anciano , Secuencia de Bases , Estudios de Casos y Controles , Niño , Preescolar , Heces/virología , Microbiología de Alimentos , Alemania/epidemiología , Hepatitis A/sangre , Hepatitis A/transmisión , Hepatitis A/virología , Humanos , Técnicas para Inmunoenzimas , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Análisis Multivariante , Vigilancia de la Población , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Medición de Riesgo , Factores de Riesgo , Adulto Joven
5.
Artículo en Ruso | MEDLINE | ID: mdl-23297630

RESUMEN

AIM: Evaluate the effectiveness of multiplex reverse transcription (RT) and polymerase chain reaction with fluorescence detection in real time mode (qPCR) methods for differential detection of 11 groups of intestine viruses (adenoviruses, enteroviruses, polioviruses, hepatitis A and E viruses, group A and C rotaviruses, orthoreoviruses, noroviruses, sapoviruses and astroviruses) in various biological samples. MATERIALS AND METHODS: Panels of virus isolates and clinical samples characterized by reference methods were used to evaluate sensitivity of detection of various intestine viruses. Nucleic acids were isolated from study samples and multiplex RT and qPCR were carried out. RESULTS: Sensitivity of laboratory reagent kit (LRK) when compared with results obtained from reference methods was 100% for rotavirus A, adenovirus, enterovirus and norovirus, 88.9% for hepatitis E virus and 92.3% for hepatitis A virus, and diagnostic specificity - 99.4%. During analysis of 697 clinical samples from patients with acute intestine infection symptoms nucleic acids of various intestine viruses were isolated in 71.7%. CONCLUSION: Multiplex qRT-PCR was shown as an effective method of etiologic diagnostics of an intestine viral infection. Use of LRK was demonstrated to establish etiology of intestine diseases in 63 - 72% and in children with watery diarrhea - in approximately 90% of cases.


Asunto(s)
Intestinos/virología , Virosis/diagnóstico , Virosis/epidemiología , Adenoviridae/genética , Adenoviridae/aislamiento & purificación , Adulto , Niño , Diagnóstico Diferencial , Enterovirus/genética , Enterovirus/aislamiento & purificación , Femenino , Fluorescencia , Hepatovirus/genética , Hepatovirus/aislamiento & purificación , Humanos , Masculino , Mamastrovirus/genética , Mamastrovirus/aislamiento & purificación , Reacción en Cadena de la Polimerasa Multiplex/métodos , Norovirus/genética , Norovirus/aislamiento & purificación , Orthoreovirus/genética , Orthoreovirus/aislamiento & purificación , Poliovirus/genética , Poliovirus/aislamiento & purificación , Juego de Reactivos para Diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Rotavirus/genética , Rotavirus/aislamiento & purificación , Federación de Rusia/epidemiología , Sapovirus/genética , Sapovirus/aislamiento & purificación , Virosis/virología
7.
Artículo en Chino | MEDLINE | ID: mdl-19544642

RESUMEN

OBJECTIVE: To investigate the seroprevalence of hepatitis viruses in Mianyang of the Sichuan province. METHODS: EIISA was used for detecting anti-HAV IgG, HBsAg/HBsAb, anti-HCV IgG and anti-HEV IgG of the serum samples. All sample were collected in Mianyang areas in 2007. RESULTS: 1352 samples were detected. The positive rates of anti-HAV, HBsAg/HBsAb, anti-HCV,and anti-HEV are 81.07% (1096/1352), 5.40% (73/1352) and 61.32% (829/1352), 0.37% (5/1352) and 49.26% (666/1352), respectively. The positive rate at different age group, for anti-HAV was 38.21% of 10-19 years old, 83% of 20-29 years old, 88% of 30-39 years old, 95.03% of 40-49 years old, 97% of 50-59 years old, 97.77% of 60-69 years old, 97.52% of > or =70 years old. For HBsAg/HBsAb were 5.65% or 50.83%, 10.0% or 68.0%, 5.20% or 78.80%, 5.97% or 78.11%, 6.50% or 62.50%, 1.12% or 51.40%, 4.96% or 30.58% at the same age group, respectively,for anti-HCV, was 0.33% of 10-19 years old, 0.80% of 30-39 years, 0.56% of 60-69 years old, 0.83% of > or =70 years old.For HEV-IgG was 26.58% of 10-19 years old, 42.0% of 20-29 years old, 55.22%-61.0% of 30-> or =70 years old, for anti-HEV IgM, was 10.06% (53/527) in the positive samples of HEV-IgG. CONCLUSION: The inoculation againt HAV and HBV is enhanced in the young population. HBsAg carrier and HCV infection is decreasing. The HEV infection is actually increasing.


Asunto(s)
Hepatitis A , Anticuerpos Antihepatitis/sangre , Hepatitis B , Hepatitis C , Estudios Seroepidemiológicos , Adolescente , Adulto , Anciano , Anticuerpos Antiidiotipos/sangre , Anticuerpos Antivirales/sangre , Niño , China/epidemiología , Femenino , Hepacivirus/inmunología , Hepacivirus/aislamiento & purificación , Hepatitis A/epidemiología , Hepatitis A/inmunología , Anticuerpos Antihepatitis/clasificación , Hepatitis B/epidemiología , Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis C/epidemiología , Hepatitis C/inmunología , Hepatovirus/clasificación , Hepatovirus/inmunología , Hepatovirus/aislamiento & purificación , Humanos , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Adulto Joven
8.
Acta gastroenterol. latinoam ; 36(4): 182-189, dic. 2006. tab, graf
Artículo en Español | LILACS | ID: lil-459130

RESUMEN

La infección por el virus de hepatitis A (HAV) es endémica en Argentina. El uso de técnicas moleculares permitió extender la detección del RNA del HAV en sueroy heces en pacientes con diferentes presentaciones clínicas. Comparamos la sensibilidad del protocolo de RT-PCR que usamos con cebadores dirigidos a distintas regiones del genoma, resultando la detección de la región VP3 C terminal la más sensible. Se obtuvieron prospectivamente muestras de suero y materia fecal de 20 niños con hepatitis aguda autolimitada por HAV. El RNA del HAV fue detectado en 18/20 niños en muestras basales y en 19/20 sumando una muestra posterior. El RNA del HAV fue detectable en 9/20 acientes hasta 30 días en suero; en materia fecal en 2/20 hasta 60 días y en 1/20 hasta 90 días. La secuencia genómica para la región VP1/2A en 8 muestras demostró que todas pertenecían al subgenotipo IA, aunque eran diferentes entre sí. Solo en 1/11 niños con falla hepatica fulminante fue posible la detección del RNA del HAV utilizando la región VP3 C terminal y el genotipo fue I. La reciente introducción de la vacunación universal en niños de 1 año de edad en Argentina podría disminuir drásticamente la circulación del virus, emergiendo nuevas fuentes de infección y permitiendo la introducción de nuevos genotipos. Las técnicas moleculares aplicadas al estudio de la historia natural de la infección y a la vigilancia epidemiológica contribuyenal control y la toma de decisiones eficientes en políticas de Salud Pública.


Hepatitis A virus (HAV) infection is endemic in Argentina. Molecular tools have allowed HAV RNA detection to be extent to sera and feces from patients with different clinical backgrounds. We compare the sensitivity of the RT-PCR protocol we follow using primers targeting different genomic regions and VP3 C terminal was the most sensitive. Sequential sera and fecal samples were obtained from 20 children with acute self limited Hepatitis A. HAV RNA was detectable in 18/20 children if sera and stool specimens were collected at the onset of symptoms and in 19/20 if a later sample was considered. HAV RNA was detectable in serum from 9/20 patients until day 30 and in feces from 2 patients until day 60 and until day 90 in one. Genomic sequences from VP1/2A region in 8 samples showed they all belong to subgenotype IA although they were different between them. HAV RNA was detectable only in 1/11 sera from children with acute liverfailure when VP3 C terminal fragment was searched and it belonged to genotype I. Universal vaccination in one year old children was recently implemented in Argentinaand it will dramatically enable the decrease of the viral circulation, making new sources of infection emerge and allowing the introduction of new genotypes. The application of molecular tools to the study of the natural history of infection and to the epidemiologicsurveillance may contribute to efficient control and lead to rational decisions in public health policies.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Adolescente , Heces/virología , Hepatitis A/diagnóstico , Hepatovirus/aislamiento & purificación , Viremia/virología , Esparcimiento de Virus , Enfermedad Aguda , Hepatitis A/complicaciones , Hepatitis A/virología , Hepatovirus/genética , Fallo Hepático Agudo/sangre , Fallo Hepático Agudo/virología , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Estudios Prospectivos , ARN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Factores de Tiempo
9.
Epidemiol Infect ; 134(6): 1292-8, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16650329

RESUMEN

In April 2004, increased numbers of hepatitis A were noted in six neighbouring districts in Germany. Exploratory interviews showed that patients had consumed bakery products from company X where two employees had been diagnosed with hepatitis A in February. A case-control study of consumption of products of company X was carried out through telephone interviews. Altogether, 64 cases were identified. Fifty-two cases and 112 controls aged >or=16 years were included in the case-control study. In total, 46/52 cases and 37/112 controls had consumed company X products [odds ratio (OR) 15.5, 95% confidence interval (CI) 6.1-39.7]. Of these, 36/46 cases and 16/37 controls had consumed pastries (OR 4.7, 95% CI 1.8-12.3), 25/46 cases and 12/37 controls had consumed filled doughnuts (OR 2.5, 95% CI 1.0-6.1). Sequence analysis of the VP1-2A junction region indicated 100% strain homology between cases and an infected employee of company X. We recommended reinforcement of hygiene precautions, and consideration of a prolongation of compulsory work absence after post-exposure vaccination.


Asunto(s)
Brotes de Enfermedades , Microbiología de Alimentos , Hepatitis A/epidemiología , Hepatovirus/genética , Estudios de Casos y Controles , Recolección de Datos , Enfermedades Transmitidas por los Alimentos , Alemania/epidemiología , Hepatitis A/transmisión , Hepatitis A/virología , Hepatovirus/aislamiento & purificación , Humanos , Higiene , Entrevistas como Asunto
10.
Acta Gastroenterol Latinoam ; 36(4): 182-9, 2006 Dec.
Artículo en Español | MEDLINE | ID: mdl-17225445

RESUMEN

Hepatitis A virus (HAV) infection is endemic in Argentina. Molecular tools have allowed HAV RNA detection to be extent to sera and feces from patients with different clinical backgrounds. We compare the sensitivity of the RT-PCR protocol we follow using primers targeting different genomic regions and VP3 C terminal was the most sensitive. Sequential sera and fecal samples were obtained from 20 children with acute self limited Hepatitis A. HAV RNA was detectable in 18/20 children if sera and stool specimens were collected at the onset of symptoms and in 19/20 if a later sample was considered. HAV RNA was detectable in serum from 9/20 patients until day 30 and in feces from 2 patients until day 60 and until day 90 in one. Genomic sequences from VP1/2A region in 8 samples showed they all belong to subgenotype IA although they were different between them. HAV RNA was detectable only in 1/11 sera from children with acute liver failure when VP3 C terminal fragment was searched and it belonged to genotype I. Universal vaccination in one year old children was recently implemented in Argentina and it will dramatically enable the decrease of the viral circulation, making new sources of infection emerge and allowing the introduction of new genotypes. The application of molecular tools to the study of the natural history of infection and to the epidemiologic surveillance may contribute to efficient control and lead to rational decisions in public health policies.


Asunto(s)
Heces/virología , Hepatitis A/diagnóstico , Hepatovirus/aislamiento & purificación , Viremia/virología , Esparcimiento de Virus , Enfermedad Aguda , Adolescente , Niño , Preescolar , Femenino , Hepatitis A/complicaciones , Hepatitis A/virología , Hepatovirus/genética , Humanos , Lactante , Fallo Hepático Agudo/sangre , Fallo Hepático Agudo/virología , Masculino , Datos de Secuencia Molecular , Estudios Prospectivos , ARN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Factores de Tiempo
12.
J Biochem Mol Biol ; 38(4): 399-406, 2005 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-16053706

RESUMEN

A sensitive method for detection of Hepatitis A virus (HAV) by utilizing gold-DNA probe on an array was developed. Amino-modified oligodeoxynucleotides at the 5' position were arrayed on an activated glass surface to function as capture probes. Sandwich hybridization occurred among capture probes, the HAV amplicon, and gold nanoparticlesupported oligonucleotide probes. After a silver enhancement step, signals were detected by a standard flatbed scanner or just by naked eyes. As little as 100 fM of HAV amplicon could be detected on the array. Therefore, the array technology is an alternative to be applied in detection of HAV due to its low-cost and high-sensitivity.


Asunto(s)
ADN Viral/análisis , Oro/química , Hepatovirus/genética , Nanotubos/química , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Sondas de Oligonucleótidos/química , ADN Viral/química , ADN Viral/ultraestructura , Hepatovirus/aislamiento & purificación , Humanos , Microscopía Electrónica de Transmisión , Nanotubos/ultraestructura , Hibridación de Ácido Nucleico , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
J Virol Methods ; 125(2): 111-8, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15794979

RESUMEN

Environmental samples and contaminated shellfish present frequently low concentrations of more than one viral species. For this reason, a nested multiplex RT-PCR was developed for the detection of adenoviruses, enteroviruses and hepatitis A viruses in different environmental samples such as urban sewage and shellfish. This assay will save time and cost for detection of these enteric viruses with a smaller sample volume, which otherwise can be a limiting factor in routine analysis. The limit of detection was approximately 1 copy for adenovirus and 10 copies for enterovirus and hepatitis A virus per PCR reaction using titrated cell-cultured viruses as template material. In shellfish and environmental samples, this multiplex PCR was optimized to detect all three viruses simultaneously when the concentration of each virus was equal or lower than 1000 copies per PCR reaction. This is the level found predominantly in the environment and in shellfish when the numbers of fecal bacterial and phage indicators are low. The detection of human adenoviruses by PCR has been suggested as a molecular index of fecal contamination of human origin in the environment and food and the multiplex assay developed may be a tool for evaluating the presence of viral contamination in shellfish and water and to expand microbiological control to include viral markers.


Asunto(s)
Enterovirus/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Aguas del Alcantarillado/virología , Mariscos/virología , Microbiología del Agua , Adenovirus Humanos/genética , Adenovirus Humanos/crecimiento & desarrollo , Adenovirus Humanos/aislamiento & purificación , Animales , Enterovirus/genética , Enterovirus/crecimiento & desarrollo , Hepatovirus/genética , Hepatovirus/crecimiento & desarrollo , Hepatovirus/aislamiento & purificación , Humanos , Sensibilidad y Especificidad
14.
Int J Food Microbiol ; 77(1-2): 125-33, 2002 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-12076030

RESUMEN

The consumption of shellfish has been associated with viral infections even in cases where shellfish complied with the current regulation, which is based on bacterial analysis. In this study, depuration rates of potential indicators and human viruses have been analysed in order to study the use of complementary parameters for evaluating the microbiological quality of depurated shellfish. Depuration of naturally highly polluted mussels has been evaluated and analyses for Escherichia coli, Clostridium perfringens, somatic coliphages, F-RNA phages and bacteriophages infecting Bacteroides fragilis RYC2056 and HSP40, human adenovirus, enterovirus have been done. Seawater of the depuration tank was disinfected by UV irradiation, ozone and passed through a skimmer and a biological filter. The correct functioning of the depuration tank was monitored by the quantification of total organic carbon (TOC), NH4+ and total aerobic bacteria in the seawater. To study the relation between the bacteriophages and the human viruses analysed, a logistic regression model was applied. F-RNA phages are significantly related to human adenoviruses and enteroviruses. Thus, they can be used as a complementary parameter for evaluating the efficiency of the depuration treatment. Somatic coliphages are also significantly associated with enteroviruses. Bacteriophages infecting B. fragilis HSP40 were analysed by the double-agar-layer (DAL) method, which quantifies infectious viruses, and by nested PCR, which detects the presence of the genome of these phages. The highest sensitivity of the molecular techniques was demonstrated and the results obtained are an indicator of a close relation between positive results by PCR and the presence of infectious viral particles in shellfish. All shellfish samples were negative for human viruses by PCR after 5 days of depuration treatment and the results obtained applying a regression model also showed negative results or nearly for F-RNA phages and bacteriophages infecting B. fragilis RYC2056. Thus, in this specific depuration treatment, 5 days may be necessary to assess the sanitary quality of shellfish.


Asunto(s)
Bivalvos/virología , Oxidantes Fotoquímicos/farmacología , Mariscos/virología , Adenoviridae/aislamiento & purificación , Animales , Bacteriófagos/aislamiento & purificación , Bacteroides fragilis/virología , Enterovirus/aislamiento & purificación , Hepatovirus/aislamiento & purificación , Humanos , Ozono/farmacología , Rayos Ultravioleta , Microbiología del Agua , Contaminación del Agua
15.
Artículo en Ruso | MEDLINE | ID: mdl-11550556

RESUMEN

Seroepidemiological study of hepatitis A (HA) morbidity was carried out in three Russian cities, with different levels of HA morbidity. The study included the analysis of HA morbidity for 22 years, the determination of antibodies to HA virus (anti-HAV) in 2,958 healthy persons aged 0-12 months to 40 years and older. In one of the cities 7 isolates of HA virus were obtained from unrelated sources and the genotypes of the virus were determined. The study revealed that the frequency of seropositive cases among persons of different ages correlated with the level and prolonged dynamics of HA morbidity. According to the occurrence of anti-HAV, such cities as St. Petersburg, Rostov-on-Don and Yakutsk may be at present classified as territories, moderately endemic in HA. At the same time in the 90 s the epidemic situation in HA was more favorable in Rostov-on-Don than in two other cities. The suggestion was made that a high proportion of seropositive persons among the population of St. Perersburg was linked with an almost twofold rise in HA morbidity in 1993-1995 caused by genotype 1 of the virus. Seroepidemiological studies in HA during the period of a drop in morbidity acquire special importance in the surveillance and control system of this infection.


Asunto(s)
Brotes de Enfermedades , Hepatitis A/epidemiología , Hepatovirus/aislamiento & purificación , Adolescente , Adulto , Antígenos Virales/sangre , Niño , Preescolar , Genotipo , Hepatitis A/inmunología , Hepatitis A/virología , Hepatovirus/clasificación , Hepatovirus/genética , Humanos , Técnicas para Inmunoenzimas , Lactante , Recién Nacido , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Federación de Rusia/epidemiología
16.
Clin Diagn Lab Immunol ; 8(5): 984-92, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11527815

RESUMEN

We have investigated the clonality of beta-chain T-cell receptor (TCR) transcripts from the cerebrospinal fluid (CSF) and peripheral blood from a 7-year old child who developed a multiphasic disseminated encephalomyelitis following an infection with hepatitis A virus. We amplified beta-chain TCR transcripts by nonpalindromic adaptor (NPA)-PCR-Vbeta-specific PCR. TCR transcripts from only five Vbeta families (Vbeta13, Vbeta3, Vbeta17, Vbeta8, and Vbeta20) were detected in CSF. The amplified products were combined, cloned, and sequenced. Sequence analysis revealed in the CSF substantial proportions of identical beta-chain of TCR transcripts, demonstrating oligoclonal populations of T cells. Seventeen of 35 (48%) transcripts were 100% identical, demonstrating a major Vbeta13.3 Dbeta2.1 Jbeta1.3 clonal expansion. Six of 35 (17%) transcripts were also 100% identical, revealing a second Vbeta13 clonal expansion (Vbeta13.1 Dbeta2.1 Jbeta1.2). Clonal expansions were also found within the Vbeta3 family (transcript Vbeta3.1 Dbeta2.1 Jbeta1.5 accounted for 5 of 35 transcripts [14%]) and within the Vbeta20 family (transcript Vbeta20.1 Dbeta1.1 Jbeta2.4 accounted for 3 of 35 transcripts [8%]). These results demonstrate the presence of T-cell oligoclonal expansions in the CSF of this patient following infection with hepatitis A virus. Analysis of the CDR3 motifs revealed that two of the clonally expanded T-cell clones exhibited substantial homology to myelin basic protein-reactive T-cell clones. In contrast, all Vbeta TCR families were expressed in peripheral blood lymphocytes. Oligoclonal expansions of T cells were not detected in the peripheral blood of this patient. It remains to be determined whether these clonally expanded T cells are specific for hepatitis A viral antigen(s) or host central nervous system antigen(s) and whether molecular mimicry between hepatitis A viral protein and a host protein is responsible for demyelinating disease in this patient.


Asunto(s)
Encefalomielitis Aguda Diseminada/líquido cefalorraquídeo , Encefalomielitis Aguda Diseminada/inmunología , Hepatitis A/líquido cefalorraquídeo , Hepatovirus/inmunología , Subgrupos de Linfocitos T/inmunología , Secuencia de Aminoácidos , Niño , Células Clonales , Enfermedades Desmielinizantes/líquido cefalorraquídeo , Enfermedades Desmielinizantes/diagnóstico , Enfermedades Desmielinizantes/inmunología , Encefalomielitis Aguda Diseminada/diagnóstico , Femenino , Hepatitis A/diagnóstico , Hepatovirus/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Estudios Retrospectivos , Subgrupos de Linfocitos T/virología
19.
J Virol Methods ; 94(1-2): 25-35, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11337037

RESUMEN

Hepatitis A is one of the major infectious diseases epidemiologically associated with worldwide shellfish consumption. Molecular detection using polymerase chain reaction (PCR) to detect hepatitis A virus (HAV) in contaminated shellfish can be hindered by low virus recoveries during the concentration process and by natural PCR inhibitors in shellfish. This study evaluated and modified two major steps of a processing procedure for virus concentration from oysters: acid adsorption-elution and solvent extraction. With the addition of second and third elutions, the acid adsorption-elution step doubled the recovery to 46% of HAV seeded initially. Extraction with chloroform or chloroform-butanol resulted in lower HAV detection limits by reverse transcription-PCR (RT-PCR)-oligoprobing than extraction with the fluorocarbon, Freon. These results led to the following modified procedure: HAV was acid adsorbed at pH 4.8, eluted first with 0.05 M glycine, second with 0.5 M threonine, PEG-precipitated twice, chloroform-extracted twice, RNA-extracted, and RT-PCR (single round) amplified. Using the modified procedure, HAV was detected by RT-PCR in all trials with a seeding density of > or = 1 plaque forming unit (PFU)/g of oyster, and in which the equivalent detection limit was 0.33 PFU of HAV seeded per RT-PCR reaction (corresponding to 111 PCR units). The method developed is capable of detecting low levels of HAV in oysters environmentally contaminated.


Asunto(s)
Hepatovirus/aislamiento & purificación , Ostreidae/virología , Animales , Línea Celular , Sondas de ADN , Hepatovirus/genética , Humanos , Macaca mulatta , Oligodesoxirribonucleótidos , Solventes , Agua
20.
Can J Microbiol ; 47(2): 153-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11261495

RESUMEN

This study applied the integrated cell culture/polymerase chain reaction methodology (ICC/PCR) for rapid and specific detection of both cytopathogenic and noncytopathogenic viruses. Results of this study showed that the use of direct RT-PCR or conventional cell culture alone may yield erroneous results with the analysis of environmental samples. The purpose of this study was to compare cultural, molecular, and combined assays for the most effective method of virus detection in variable environmental samples. Using ICC/PCR, stock enterovirus inocula of > or =10 PFU were PCR positive in at least 4/5 replicate flasks after only 5 h of incubation in cell culture, and in all flasks after > or =10 h. An inoculum of one PFU was detected by PCR after 20 h of cell culture incubation while for concentrations of virus below one PFU, 25 h of incubation was sufficient. Similarly, hepatitis A virus (HAV) inocula of 100 MPN/flask, produced indeterminate CPE in cell culture, but were clearly detected by ICC/PCR following 48 h of incubation. Lower levels of HAV, 1 and 10 MPN, were detected by ICC/PCR after 96 to 72 h of incubation, respectively. Cell culture lysates from 11 environmental sample concentrates of sewage, marine water, and surface drinking water sources, were positive for enteroviruses by ICC/PCR compared to 3 positive by direct RT-PCR alone. Results from ICC/PCR eventually agreed with cell culture but required < or =48 h of incubation, compared to as long as 3 weeks for CPE following incubation with BGM and FRhK cells.


Asunto(s)
Enterovirus/aislamiento & purificación , Microbiología Ambiental , Hepatovirus/aislamiento & purificación , Técnicas de Cultivo de Célula/métodos , Agua Dulce/microbiología , Reacción en Cadena de la Polimerasa/métodos , Sensibilidad y Especificidad , Aguas del Alcantarillado/microbiología
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