101 resultados para Viral genotyping


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INTRODUÇÃO: Os métodos de genotipagem do vírus da hepatite C têm sido muito discutidos. O objetivo deste trabalho foi comparar as metodologias de hibridização reversa e sequenciamento direto para a genotipagem do vírus da hepatite C. MÉTODOS: Noventa e uma amostras de plasma de pacientes assistidos na Faculdade de Medicina de Botucatu da Universidade Estadual Paulista foram utilizadas. A genotipagem por hibridização reversa foi realizada utilizando o kit comercial INNO-LiPA® v.1.0. O sequenciamento direto foi efetuado em sequenciador automático utilizando protocolos in house. RESULTADOS: A genotipagem por sequenciamento direto mostrou-se eficiente na resolução dos resultados inconclusivos pelo kit comercial. O kit mostrou resultados errôneos em relação à subtipagem viral. Além disso, a genotipagem por sequenciamento direto revelou um erro do kit com relação à determinação genotípica questionando a eficiência do método também para a identificação do genótipo viral. CONCLUSÕES: A genotipagem realizada por meio de sequenciamento direto permite uma maior acurácia na classificação viral quando comparada à hibridização reversa.

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From 111 dogs with neurological signs admitted in this research in a 22-month period, brain samples of 34 animals were inoculated in mice in order to isolate Toxoplasma gondii. From these 34 dogs, 9 strains of T. gondii were isolated and the genetic characterization performed by restriction analysis (RFLP) of the SAG-2 gene. RFLP analysis showed that four of them were classified as Type I, and five as Type Ill. The present report is the first description of genotyping of T. gondii isolated from brain samples of naturally infected dogs, in Brazil. (C) 2004 Elsevier B.V. All rights reserved.

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The first experimental data suggesting that neoplasm development in animals might be influenced by infectious agents were published in the early 1900s. However, conclusive evidence that DNA viruses play a role in the pathogenesis of some human cancers only emerged in the 1950s, when Epstein-Barr virus (EBV) was discovered within Burkitt lymphoma cells. Besides EBV, other DNA viruses consistently associated with human cancers are the hepatitis B virus (HBV), human papillomavirus (HPV), and Kaposi sarcoma herpesvirus (KSHV). Although each virus has unique features, it is becoming clearer that all these oncogenic agents target multiple cellular pathways to support malignant transformation and tumor development. (c) 2006 Elsevier B.V.. All rights reserved.

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It has been hypothesized that the AR (androgen receptor) gene binds the two PSA (prostate-specific antigen) alleles with differing affinities and may differentially influence prostate cancer risk. In this article, we report a case of adenocarcinoma of the prostate in a 56-year-old man with Klinefelter syndrome (47,XXY) and non-Hodgkin lymphoma, as well as the AR and PSA genotype. AR and PSA gene polymorphisms were analyzed by polymerase chain reaction-based methods using DNA from peripheral white blood cells and the prostate cancer. We determined the methylation status of the AR gene on the X chromosome. The patient presents with the AG genotype for the ARE-I (androgen response element) region of the PSA gene. We detect the presence of two short AR alleles with 19 and 11CAG repeats each. Unmethylated alleles were demonstrated for both. The shorter allele was inactive in more than 60% of total DNA in both control blood and prostate cancer cells. The presence of short AR alleles and the G allele of the PSA gene may contribute to the development of prostate cancer in a 47,XXY patient. (C) 2004 Elsevier B.V. All rights reserved.

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Epidermodysplasia verruciformis (EV) is triggered by a variety of mechanisms that at least partly include genetic background. We present a Brazilian man with a 30-year history of flat, wart-like lesions with clinical, histopathological, and evolutive aspects consistent with papillomavirus (HPV)-associated EV. Histological analysis of the wart lesions showed epidermis with hyperkeratosis, regular acanthosis, hypergranulosis, and cells with abundant basophilic cytoplasm. Moreover, a perivascular lymphocytic infiltrate was found in the superficial dermis, consistent with a viral wart. Type-2-HPV DNA was detected in various fragments of skin-wart lesions using the polymerase chain reaction (PCR). Two years after the EV diagnosis, the patient presented with an anesthetic well-demarcated, erythematous and mildly scaly plaque on his right forearm. A histopathological analysis of this lesion demonstrated the presence of a compact tuberculoid granuloma. Ziehl-Neelsen staining demonstrated the presence of rare acid-fast bacilli and confirmed the tuberculoid leprosy diagnosis. The patient's Mitsuda Intradermal Reaction was positive. To elucidate the possible mechanism involved in this case of EV, we genotyped the HLA genes of this patient. DQB genotyping showed the polymorphic HLA alleles DQB1*0301 and 0501. The patient was treated with a paucibacillary multidrug therapy scheme, and the disease was cured in six months. This report describes an EV patient with an M. leprae infection, confirming that tuberculoid leprosy patients possess a relatively specific and efficient cell-mediated immunity against the bacillus and, therefore, localized forms of the disease. Moreover, we show the possible involvement of the polymorphic HLA alleles DQB1*0301 and 0501 in EV induction mechanisms.

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This study investigated the occurrence of equine arteritis virus antibodies using neutralization test in 1,400 horses from Campinas and macro metropolitan paulista mesoregions located at São Paulo State, between 2007 and 2008. Eighty (5.7%) samples showed antibodies to virus (titers from 4 to 4,096). Among the 42 cities, 15 (35.7%) presented at least one seropositive animal to equine arteritis virus. of the 238 farms analyzed 41 showed at least one seropositive animal. The occurrence was higher in sport horses like jumping horses, Quarter horses and was similar for female and male. The rate of seropositive was higher in animals older than 24 months of age. These results suggest the virus circulation among horse population in studied farms, and the need for continuing epidemiological surveillance studies.

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Synanthropic rodents, mainly rats and mice, become ecologically associated with men due to changes in their ecosystems caused by human activities. These animals may take part in the epidemiological cycles of several diseases, including toxoplasmosis. The presence of serum antibodies to Toxoplasma gondii in 43 rodents captured in the urban area of Umuarama, PR, Brazil, was verified by modified agglutination test (MAT). Brain and heart samples were also collected and bioassayed in mice for the isolation of the parasite. Isolated samples were analyzed by 12 multilocus genotyping. Although all rodents were seronegative, the parasite was isolated in one mouse (Mus musculus) and one rat (Rattus rattus). Genotyping showed that these samples were similar to those previously isolated from cats in the state of Parana, Brazil. (C) 2010 Elsevier B.V. All rights reserved.

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Although progression of fibrosis in the chronic hepatitis C depends on environmental, viral, and host factors, genetic polymorphisms have been associated recently with this progression, including the expression of integrins, adhesion proteins. Some integrins expressed on the platelet membrane show polymorphic antigenic determinants called human platelet antigens (HPA), where the major ones are HPA-1, -3, -5. The association between HCV infection and HPA-5b has been demonstrated. Similarly, the HPA profile could determine if HPA is related to progression of fibrosis. The goal of this study was to evaluate the association between the frequencies of HPA-1, -3, and -5 and degree of fibrosis in HCV-infected patients. Genomic DNA from 143 HCV-infected patients was used as the source for HPA genotyping by PCR-SSP or PCR-RFLP. Progression of fibrosis was evaluated using the METAVIR scoring system, and the patients were grouped according to degree of fibrosis into G1 (n = 81, with F1, portal fibrosis without septa or F2, few septa) and G2 (n = 62, with F3, numerous septa, or F4, cirrhosis). Statistical analysis was performed using the proportional odds model. The genotypic frequency of HPA-1a/1b was significantly higher in the patients in G2. To evaluate the influence of the time of infection to the development of fibrosis and its effect on the genetic factor HPA-1, 96 patients from 143 studied were evaluated considering the time of HCV infection, and these results suggest that the HPA-1a/1b genotype promotes the development of fibrosis in HCV infection with time. J. Med. Virol. 84: 56-60, 2012. (C) 2011 Wiley Periodicals, Inc.

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Ocimum basilicum L., popularly known as sweet basil, is a Lamiaceae species whose essential oil is mainly composed of monoterpenes, sesquiterpenes and phenylpropanoids. The contents of these compounds can be affected by abiotic and biotic factors such as infections caused by viruses. The main goal of this research was an investigation of the effects of viral infection on the essential oil profile of common basil. Seeds of O. basilicum L. cv. Genovese were sowed and kept in a greenhouse. Plants presenting two pairs of leaves above the cotyledons were inoculated with an unidentified virus isolated from a field plant showing chlorotic yellow spots and foliar deformation. Essential oils of healthy and infected plants were extracted by hydrodistillation and analyzed by GCMS. Changes in essential oil composition due to viral infection were observed. Methyleugenol and p-cresol,2,6-di-tert-butyl were the main constituents. However, methyleugenol contents were significantly decreased in infected plants.

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O Vírus da leucemia felina (FeLV) pertence à família Retroviridae, gênero Gammaretrovirus. Diferentemente de outras retroviroses, uma parcela dos gatos jovens e adultos exposta ao FeLV não apresenta antigenemia/viremia, de acordo com as técnicas convencionais de detecção viral, como isolamento em cultivo celular, imunofluorescência direta e ELISA. O emprego de técnicas de maior sensibilidade para detecção e quantificação viral, como o PCR quantitativo, permitiu a identificação de animais positivos para a presença de DNA proviral e RNA na ausência de antigenemia/viremia e, com isso, um refinamento da análise das diferentes evoluções da infecção. Assim, reclassificou-se a patogenia do FeLV em 4 categorias: infecção abortiva, regressiva, latente e progressiva. Foi possível também detectar DNA proviral e RNA em animais considerados imunes ao FeLV após vacinação. Diante disso, os objetivos desta revisão de literatura foram demonstrar as implicações da utilização de técnicas sensíveis de detecção viral na interpretação e classificação da infecção do FeLV e rever as técnicas de detecção do vírus para fins de diagnóstico. Além disso, apresentar os resultados referentes à eficácia da vacinação contra o FeLV com a utilização dessas técnicas.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)