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‣ Rabies virus distribution in tissues and molecular characterization of strains from naturally infected non-hematophagous bats

Allendorf, Susan Dora; Cortez, Adriana; Heinemann, Marcos Bryan; Appolinario Harary, Camila M.; Antunes, Joao Marcelo A. P.; Peres, Marina Gea; Vicente, Acacia Ferreira; Sodre, Miriam Martos; da Rosa, Adriana Ruckert; Megid, Jane
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 119-125
Português
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Bats are main reservoirs for Lyssavirus worldwide, which is an important public health issue because it constitutes one of the big challenges in rabies control. Yet, little is known about how the virus is maintained among bats, and the epidemiological relationships remain poorly understood. The aim of the present study was to investigate the distribution of the rabies virus (RABV) in bat tissues and organs and to genetically characterize virus isolates from naturally infected non-hematophagous bats. The heminested reverse transcriptase polymerase chain reaction (hnRT-PCR) and sequencing using primers to the nucleoprotein coding gene were performed. The results showed a dissemination of the RABV in different tissues and organs, particularly in the salivary glands, tongue, lungs, kidneys, bladder, intestine and feces, suggesting other possible forms of RABV elimination and the possibility of transmission among these animals. The phylogenetic analysis confirmed that different variants of RABV are maintained by non-hematophagous bats in nature and have similar tissue distribution irrespective of bat species and phylogenetic characterization. (C) 2012 Elsevier B.V. All rights reserved.

‣ Detection of acute hepatitis C virus infection by ELISA using a synthetic peptide comprising a structural epitope.

Kotwal, G J; Baroudy, B M; Kuramoto, I K; McDonald, F F; Schiff, G M; Holland, P V; Zeldis, J B
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/05/1992 Português
Relevância na Pesquisa
668.5776%
An enzyme-linked immunosorbent assay (ELISA) was developed by using a synthetic polypeptide (SP) whose sequence was derived from the structural region of hepatitis C virus (HCV). Results of several coded panels of sera obtained from volunteer blood donors and patients with apparent non-A, non-B hepatitis and/or hepatitis B virus used in this ELISA were compared with those of a commercially available first-generation C-100 ELISA (using nonstructural HCV antigens), an experimental second-generation C-200/C-22 ELISA (using both structural and nonstructural HCV antigens), and recombinant immunoblot assays RIBA-I and RIBA-II. In the majority of cases, the results obtained with the HCV-SP ELISA correlated well with those obtained by RIBA-II and C-200/C-22 ELISA. In contrast, many samples that were repeatedly reactive in the C-100 ELISA results were nonreactive with RIBA and HCV-SP ELISA. In addition, HCV-SP detected HCV-specific antibody that appeared within a month of infection and coincided with the earliest increase in alanine aminotransferase. In summary, we have developed an ELISA based on a structural HCV synthetic polypeptide, HCV-SP, that has high specificity and sensitivity and is capable of detecting specific antibodies in the acute phase of HCV infection.

‣ Influenza Virus Can Enter and Infect Cells in the Absence of Clathrin-Mediated Endocytosis

Sieczkarski, Sara B.; Whittaker, Gary R.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /10/2002 Português
Relevância na Pesquisa
670.2288%
Influenza virus has been described to enter host cells via clathrin-mediated endocytosis. However, it has also been suggested that other endocytic routes may provide additional entry pathways. Here we show that influenza virus may enter and infect HeLa cells that are unable to take up ligands by clathrin-mediated endocytosis. By overexpressing a dominant-negative form of the Eps15 protein to inhibit clathrin-mediated endocytosis, we demonstrate that while transferrin uptake and Semliki Forest virus infection were prevented, influenza virus could enter and infect cells expressing Eps15Δ95/295. This finding is supported by the successful infection of cells with influenza virus in the presence of chemical treatments that block endocytosis, namely, chlorpromazine and potassium depletion. We show also that influenza virus may infect cells incapable of uptake by caveolae. Treatment with the inhibitors nystatin, methyl-β-cyclodextrin, and genistein, as well as transfection of cells with dominant-negative caveolin-1, had no effect on influenza virus infection. By combining inhibitory methods to block both clathrin-mediated endocytosis and uptake by caveolae in the same cell, we demonstrate that influenza virus may infect cells by an additional non-clathrin-dependent...

‣ Inactivation of hepatitis B virus and non-A, non-B hepatitis by chloroform.

Feinstone, S M; Mihalik, K B; Kamimura, T; Alter, H J; London, W T; Purcell, R H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1983 Português
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682.2436%
To determine whether a non-A, non-B hepatitis agent contained essential lipids, we extracted with chloroform a dilution of human plasma that contained approximately 10(4) chimpanzee infectious doses of non-A, non-B hepatitis virus and then tested for infectivity in chimpanzees. In addition, we treated a serum containing hepatitis B virus in the same way. Both of these samples were also sham extracted as controls. Known chloroform-sensitive and chloroform-resistant viruses were added directly to the hepatitis-containing serum or plasma as internal controls or to fetal calf serum as external controls and were assayed for infectivity in vitro after chloroform extraction or sham extraction. All infectivity of the diluted plasma that contained at least 10(4) chimpanzee infective doses of non-A, non-B hepatitis agent and all infectivity of the serum that contained 10(3.5) chimpanzee infective doses of hepatitis B virus were destroyed by chloroform. The chloroform-sensitive control viruses were completely inactivated, but the chloroform-resistant control viruses lost less than 0.5 log10 of infectivity. Sham-extracted non-A, non-B hepatitis agent-containing plasma was shown to maintain its infectivity in chimpanzees that had initially been inoculated with the chloroform-extracted plasma. Thus...

‣ Expression and diagnostic utility of hepatitis E virus putative structural proteins expressed in insect cells.

He, J; Tam, A W; Yarbough, P O; Reyes, G R; Carl, M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1993 Português
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The full-length putative structural proteins encoded by open reading frame 2 (ORF2) and ORF3 of hepatitis E virus have been cloned and expressed in recombinant baculovirus. Sera obtained from 28 Sudanese pediatric patients with acute hepatitis and 19 pediatric control patients were analyzed for reactivity to hepatitis E virus by using the baculovirus-expressed ORF2 and ORF3 proteins in a Western blot (immunoblot) format. Seventeen of the 18 patients classified as having non-A, non-B hepatitis, without acute antibody markers for hepatitis A, B, or C viruses, Epstein-Barr virus, or cytomegalovirus, were shown to have immunoglobulin M (IgM) antibodies to the recombinant ORF2 protein, as did two patients with chronic hepatitis B, three of seven patients with acute hepatitis A, and one patient with acute hepatitis B. None of the 19 control patients had IgM antibodies against the ORF2 or ORF3 proteins. The Western blot assay using the baculovirus-expressed ORF3 protein did not appear to be as sensitive as the assay based on the ORF2 protein. Only 10 of the patients classified as having non-A, non-B hepatitis had IgM antibodies to the baculovirus-expressed ORF3 protein. We conclude that a Western blot assay which uses a baculovirus-expressed ORF2 protein is both sensitive and specific for diagnosing acute hepatitis E.

‣ Development of an enzyme immunoassay using recombinant expressed antigen to detect hepatitis delta virus antibodies.

Puig, J; Fields, H A
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1989 Português
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Two generic enzyme immunoassays (EIAs) were developed for detection of anti-hepatitis delta virus antibodies (anti-HD) and compared with a commercially available radioimmunoassay. Both generic assays were configured as blocking assays and used hepatitis delta antigen (HDAg) derived from infected chimpanzee liver (EIA-1) or from Escherichia coli transformed with a plasmid containing an insert from within an open reading frame encoding HDAg (EIA-2). Absolute sensitivity was ascertained by endpoint titration, which demonstrated essentially identical endpoints for EIA-1 and EIA-2. The absolute sensitivities of the EIAs were approximately four times greater than that of the radioimmunoassay. Specificity and sensitivity were ascertained by testing a panel of 176 serum specimens by each assay. The specimens were selected to represent a panel composed of sera from individuals with or without markers of viral hepatitis as follows: (i) serologically confirmed by exclusion as posttransfusion non-A, non-B hepatitis; (ii) acute or chronic hepatitis B virus infection, positive for hepatitis B surface antigen; (iii) resolved hepatitis B virus infection, positive for anti-hepatitis B surface antigen; (iv) acute hepatitis A virus infection, positive for anti-hepatitis A virus immunoglobulin M; and (v) normal human sera. All three assays for anti-HD gave similar specificity and sensitivity values. In conclusion...

‣ Detection of immunoglobulin M antibodies to hepatitis A virus by enzyme-linked immunosorbent assay.

Møller, A M; Mathiesen, L R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1979 Português
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An enzyme-linked immunosorbent assay for the detection of immunoglobulin M (IgM) antibodies to hepatitis A virus is described. The test uses the principle of binding of IgM antibodies to anti-IgM-coated microtiter plates to determine whether the IgM antibodies attached have specificities for hepatitis A virus. In three patients with hepatitis type A followed up to 12 months, IgM antibodies to hepatitis A virus could be demonstrated from the onset of illness and during the following 2 to 3 months. When acute-phase sera from 48 patients with acute hepatitis were tested, IgM antibodies to hepatitis A virus could only be demonstrated in 18 patients previously classified as type A, whereas 30 patients with type B and non-A non-B hepatitis were negative. IgM antibodies to hepatitis A virus could not be demonstrated in 108 normal sera nor in 55 sera containing rheumatoid factor. These results indicate that the enzyme-linked immunosorbent assay for IgM antibodies to hepatitis A virus is useful in the serodiagnosis of acute hepatitis type A on a single serum sample taken during the acute phase of illness.

‣ Enzyme-linked immunosorbent assay for detection of immunoglobulin M antibody to hepatitis B core antigen.

Kryger, P; Mathiesen, L R; Møller, A M; Aldershvile, J; Hansson, B G; Nielsen, J O
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1981 Português
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An enzyme-linked immunosorbent assay for detection of specific immunoglobulin M (IgM) antibodies against the core antigen of the hepatitis B virus (anti-HBc IgM) is described. The interference of IgM rheumatoid factor was evaluated quantitatively. In the anti-HBc IgM test, the rheumatoid factor gave false-positive results when the concentration exceeded 20 IU/ml. The rheumatoid-positive sera were disclosed by a control and retested for anti-HBc IgM after absorption of rheumatoid factor with latex particles aggregated with human IgG. In five of seven selected patients with acute hepatitis B followed to biochemical and clinical recovery, anti-HBc IgM was present transiently until antibodies against hepatitis B surface antigen (anti-HBs) appeared. Two patients had persistent anti-HBc IgM during the follow-up period. Four patients with hepatitis B surface antigenemia and progression to chronic liver disease did not clear their anti-HBc IgM in the period of observation (11 to 24 months). Anti-HBc IgM could not be demonstrated in 223 of 225 Danish blood donors. The two donors found positive for anti-HBc IgM also had anti-HBs. Twenty patients with acute A or non-A non-B hepatitis were negative for anti-HBc IgM. The enzyme-linked immunosorbent assay for anti-HBc IgM described here has a high specificity and sensitivity. The diagnostic relevance needs further evaluation...

‣ Determination of immunoglobulin M antibodies against hepatitis B core antigen and hepatitis A virus by reorienting sucrose gradient high-speed centrifugation for diagnosis of acute viral-hepatitis.

Swenson, P D; Escobar, M R; Galen, E A; Carithers, R L
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1981 Português
Relevância na Pesquisa
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Immunoglobulin M (IgM) antibodies against hepatitis B core antigen (anti-HBc) and hepatitis A virus (anti-HAV) were determined in 41 cases of acute viral hepatitis. In sera positive for anti-HBc or anti-HAV, IgM was separated from IgG by reorienting sucrose gradient high-speed centrifugation, and the IgG- and IgM-containing serum fractions were tested for the presence of specific antibody by radioimmunoassay. At the onset of illness, 4 of the 41 cases were classified as hepatitis A, 31 were hepatitis B, and 6 were non-A, non-B hepatitis, based on the results of these tests and of assays for hepatitis B surface antigen and antibody and hepatitis B e antigen and antibody. Fourteen of these 41 patients (34%) required IgM anti-HBc or IgM anti-HAV testing or both for appropriate classification. IgM anti-HBc persisted for at least 7 weeks after onset but no longer than 17 weeks in all patients tested with transient hepatitis B surface antigen-positive acute hepatitis. IgM anti-HAV persisted up to but not longer than 62 days in the patients with hepatitis A. Therefore, IgM anti-HBc and IgM anti-HAV determinants are valuable tools for the differential diagnosis of acute A, B, and non-A, non-B hepatitis.

‣ A cDNA fragment of hepatitis C virus isolated from an implicated donor of post-transfusion non-A, non-B hepatitis in Japan.

Kubo, Y; Takeuchi, K; Boonmar, S; Katayama, T; Choo, Q L; Kuo, G; Weiner, A J; Bradley, D W; Houghton, M; Saito, I
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 25/12/1989 Português
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Recently, a cDNA from the hepatitis C virus (HCV) RNA genome has been isolated in the USA from a chronically infected chimpanzee. In order to isolate HCV cDNA derived from human material, RNA was extracted from plasma of a Japanese blood donor implicated in post-transfusion non-A, non-B hepatitis and HCV cDNA was synthesized and amplified by the PCR method using HCV-specific oligonucleotide primers. The cDNA fragment, 583 nucleotides long, showed 79.8% homology at the nucleotide level and 92.2% homology at the amino acid level compared with the prototype HCV cDNA. These results provides further evidence to show that HCV is closely associated with the development of post transfusion non-A, non-B hepatitis.

‣ Human linear B-cell epitopes encoded by the hepatitis E virus include determinants in the RNA-dependent RNA polymerase.

Kaur, M; Hyams, K C; Purdy, M A; Krawczynski, K; Ching, W M; Fry, K E; Reyes, G R; Bradley, D W; Carl, M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/05/1992 Português
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Hepatitis E virus is responsible for both sporadic and epidemic hepatitis in developing countries. The nonenveloped virus is 27-34 nm in diameter and has been shown to contain a single-strand, positive-sense, polyadenylylated RNA genome of approximately 7.5 kilobases. The nucleotide sequence of the Burma strain of hepatitis E virus has been reported and three open reading frames (ORFs) have been identified. The deduced amino acid sequence from each of these ORFs was used to synthesize overlapping peptides (decamers overlapping at every fourth amino acid) on a solid phase. These peptides were then tested in an ELISA with pooled acute-phase sera from known cases of enterically transmitted non-A, non-B hepatitis collected in the Sudan. Linear B-cell epitopes were identified in all three ORFs. Epitopes were identified throughout the polyprotein encoded by ORF1, but they appeared to be particularly concentrated in the region of the RNA-dependent RNA polymerase. Distinct epitopes were identified in the presumed structural protein encoded by ORF2, and one epitope was identified close to the carboxyl terminus of the protein encoded by ORF3. These data precisely pinpoint linear B-cell epitopes recognized by antibodies from patients with acute hepatitis E and identify an antibody response directed against the RNA-dependent RNA polymerase.

‣ Non-invasive investigation of liver disease in haemophilic patients.

Miller, E J; Lee, C A; Karayiannis, P; Hamilton-Dutoit, S J; Dick, R; Thomas, H C; Kernoff, P B
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1988 Português
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Liver biopsy specimens previously taken from 16 haemophilic patients with chronic non-A, non-B hepatitis were reviewed. The degree of fibrosis correlated with serum procollagen III peptide (sPIIIP) concentrations, measured both at the time of biopsy and 4.25 years later. Two patients with extremely high sPIIIP concentrations had collateral veins on computed tomography, suggesting portal hypertension. Twenty eight of 47 patients (60%) had splenomegaly on computed tomography, and of 28 patients in whom intravenous contrast medium was used, seven (25%) had collateral oesophageal veins. Serum procollagen III peptide estimations and computed tomography, both non-invasive investigations, indicated that hepatic fibrosis and portal hypertension had developed in a proportion of haemophilic patients with non-A, non-B hepatitis. Infection with the human immunodeficiency virus (HIV) may modify the course of this presumably cytopathic virus infection of the liver.

‣ Prevalence of antibody to human T-cell lymphotropic virus type I/II in people of Caribbean origin in Toronto.

Chiavetta, J; Nusbacher, J; Tam, F; Wall, A; Steaffens, J; Lee, H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/11/1992 Português
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OBJECTIVE: To estimate the prevalence of antibody to human T-cell lymphotropic virus type I/II (anti-HTLV-I/II) in people from an HTLV-I/II-endemic area (the Caribbean) living in a nonendemic region (Canada). DESIGN: Cross-sectional household survey. SETTING: Households in Toronto in 1989. PARTICIPANTS: A modified quota sampling method was used to recruit subjects of Caribbean origin as well as other Canadians. Of 2900 people invited to participate in the study 1323, 743 of Caribbean origin, were interviewed about their background and possible exposure to HTLV-I/II. MAIN OUTCOME MEASURES: Blood samples were analysed for anti-HTLV-I/II by means of an enzyme-linked immunoassay, the result being confirmed by the Western blot technique and radioimmunoprecipitation assay. The samples were also analysed for antibody to human immunodeficiency virus (anti-HIV) and hepatitis B surface antigen (HBsAg) and for surrogate markers of non-A, non-B hepatitis. RESULTS: A total of 853 blood samples (64.5%) were analysed, 483 (56.6%) from subjects of Caribbean origin. The proportion of subjects who agreed to give a blood sample was similar for the Caribbean and non-Caribbean strata. Eleven subjects, all of Caribbean origin (2.3% of the Caribbean stratum)...

‣ Risk factors for acute non-A, non-B hepatitis and their relationship to antibodies for hepatitis C virus: a case-control study.

Mele, A; Sagliocca, L; Manzillo, G; Converti, F; Amoroso, P; Stazi, M A; Ferrigno, L; Rapicetta, M; Franco, E; Adamo, B
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1994 Português
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671.0077%
A case-control study was carried out comparing 333 case subjects with non-A, non-B hepatitis and 1095 hospital control subjects. Of 333 case subjects, 197 (59%) were positive for hepatitis C antibody (anti-HCV). Excluding blood transfusion and intravenous drug use, surgical intervention and dental therapy were strongly associated with anti-HCV-positive cases: in particular, obstetric and gynecology surgical intervention was found to be strongly associated with HCV positivity (odds ratio [OR] = 32; 95% confidence interval [CI] = 7, 147). Raw shellfish consumption was a risk factor for anti-HCV-negative cases (OR = 2.2; 95% CI = 1.0, 5.1), thus suggesting an enterically transmitted virus in sporadic non-A, non-B hepatitis in Italy.

‣ Hepatitis B or non-A, non-B virus infection in multitransfused thalassaemic patients.

Moroni, G A; Piacentini, G; Terzoli, S; Jean, G; Masera, G
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1984 Português
Relevância na Pesquisa
671.96875%
We undertook a four year study of 128 thalassaemic patients who had undergone several transfusions, to determine the incidence of hepatitis B virus markers and the activities of transaminases in their sera each month. The results showed that the possibility of these patients contracting hepatitis B virus infection is still high, although on only one occasion was a transient antigenaemia found, indicating low viral replication. Furthermore, the probability of contact with hepatitis B virus increases with the number of transfusions and, therefore, with age. About 25% of these patients were positive for hepatitis B markers and 80% for other hepatitis markers including the case of cytomegalovirus hepatitis.

‣ Hepatitis virus non-A, non-B: the cause of a major public health problem in India

Tandon, B. N.; Gandhi, B. M.; Joshi, Y. K.; Irshad, M.; Gupta, H.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //1985 Português
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Serological studies of hepatitis viruses A and B were carried out on 362 patients with acute viral hepatitis, 130 with fulminant hepatitis, and 56 with subacute hepatitis, and on samples of serum from 230 subjects during epidemics of viral hepatitis. A diagnosis of non-A, non-B viral hepatitis was made when serological tests showed that anti-HAV IgM and anti-HBc IgM were absent. Hepatitis virus non-A, non-B was the causative agent responsible for 58% of cases with acute viral hepatitis, 58% with fulminant hepatitis, 87% with subacute hepatitis, and 66% with epidemic hepatitis. A considerable proportion of patients (6-32%) were infected with both hepatitis virus non-A, non-B and hepatitis virus B. Viral hepatitis non-A, non-B is probably transmitted by infection of drinking-water and is the principal cause of hepatitis in India.

‣ Failure to incriminate hepatitis B, hepatitis C, and hepatitis E viruses in the aetiology of fulminant non-A non-B hepatitis.

Mutimer, D; Shaw, J; Neuberger, J; Skidmore, S; Martin, B; Hubscher, S; McMaster, P; Elias, E
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1995 Português
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Sporadic non-A, non-B hepatitis is the most common indication for liver transplantation in patients presenting with fulminant and subacute liver failure. This study used serological, histological, and molecular biological techniques to examine specimens from 23 consecutive patients transplanted for sporadic non-A, non-B hepatitis. No evidence was found of hepatitis C virus, hepatitis E virus, or 'cryptic' hepatitis B virus infection.

‣ Prevalence of antibodies to hepatitis C virus after blood transfusion in heart surgery.

Barcena, R.; Gonzalez, A.; Martin-de-Argila, C.; Ulibarrena, C.; Graus, J.; Grande, L. A.
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /08/1994 Português
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668.77734%
We studied the frequency and time of appearance of antibodies to the hepatitis C virus (HCV) retrospectively in the sera of 127 patients who underwent heart surgery between 1983 and 1986. They received blood from volunteer donors hepatitis B surface antigen (HBsAg) negative with normal serum alanine-aminotransferase levels. A prospective follow-up was carried out every 15 days for at least 6 months from the moment of the transfusion. Of the ten patients who developed biochemical criteria of post-transfusional non-A non-B hepatitis, six seroconverted to anti-HCV (60%). Of the other 117, two were already positive before transfusion (1.51%), one patient showed antibodies only in the first post-transfusional serum (passive transfer), and another two patients with no evidence of post-transfusional hepatitis developed HCV antibodies on the 90th day, remaining indefinitely (afterwards seroconversion without hepatitis); both patients' earlier sera were anti-HCV negative. Four (40%) of the ten patients with post-transfusional hepatitis did not develop any serum markers to known hepatotropic agents. Although these findings do not exclude a viral infection by these viruses, they are consistent with the involvement of an unidentified non-A, non-B...

‣ Utilidad de la monitorización del ARN del virus de la hepatitis C durante el tratamiento antiviral como factor predictor de respuesta mantenida

Castro Bohórquez, Francisco José
Fonte: Bellaterra : Universitat Autònoma de Barcelona, Publicador: Bellaterra : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf; application/pdf; application/pdf
Publicado em //2001 Português
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678.2866%
Descripció del recurs: 9 setembre 2002; Consultable des del TDX; Títol obtingut de la portada digitalitzada; El virus de la hepatitis C (VHC) constituye la causa más prevalente de hepatitis crónica en los países desarrollados. El principal fármaco en el tratamiento de la hepatitis crónica C es el interferón. La monitorización de la respuesta a la terapia se basa en la evolución de los niveles de ALT, aunque más recientemente el desarrollo de técnicas de detección molecular del ARN del VHC ha permitido establecer la dinámica viral de la respuesta al tratamiento con interferón. En 1998 fueron publicados varios estudios que demostraron que la terapia combinada de interferón más ribavirina era más eficaz que el interferón. La dinámica viral de la respuesta a la terapia combinada no ha sido establecida. El objetivo de esta tesis es la valoración de la utilidad de la determinación del ARN de VHC durante la terapia antiviral como predictor de respuesta mantenida. Para conseguir este objetivo hemos llevado a cabo tres estudios. A) Para la evaluación de unas técnicas de RT/PCR de segunda generación en sus versiones cualitativa (Amplicor v2.0) y cuantitativa (Monitor v2.0) utilizamos tres tipos de muestras: donantes de sangre con anticuerpos Anti-VHC pero ARN no detectable por una técnica cualitativa de primera generación (n=132)...

‣ Anti-VHE IgM en casos de infección por el virus hepatitis E

Hurtado H,Carmen; Muñoz G,Gabriela; Brahm B,Javier
Fonte: Sociedad Médica de Santiago Publicador: Sociedad Médica de Santiago
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2005 Português
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Background: Hepatitis E virus is the main enterically transmitted non A non B hepatitis agent. The host IgM response in the acute infection phase is short lived. Therefore, only IgG antibodies against E virus are usually investigated. Aim: To measure IgM antibodies against virus E in serum samples. Material and Methods: IgM antibodies against virus E were measured by ELISA in 35 positive and 18 negative serum samples for IgG antibodies against hepatitis virus E, without evidence of infection with hepatitis A, B or C virus. Measurement of the same antibodies in 25 additional samples positive for IgM antibodies against hepatitis A virus but without study for hepatitis virus B or C. Results: IgM antibodies against virus E were detected in 12 of the 35 samples positive for IgG antibodies (34%) and in five of the 25 samples positive for antibodies against virus A (20%). Conclusions: An acute hepatitis E virus infection was detected in 34% of samples positive for IgG antibodies against this virus. The absence of IgM antibodies in the rest of the IgG positive samples could be due to an old or a recent virus E infection in the stage of antibody titer reduction. The detection of IgM antibodies against virus E in samples positive for virus A antibodies...