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1.
Braz. j. med. biol. res ; 42(12): 1119-1127, Dec. 2009. tab, ilus
Artigo em Inglês | LILACS | ID: lil-532293

RESUMO

Chronic hepatitis B (HBV) and C (HCV) virus infections are the most important factors associated with hepatocellular carcinoma (HCC), but tumor prognosis remains poor due to the lack of diagnostic biomarkers. In order to identify novel diagnostic markers and therapeutic targets, the gene expression profile associated with viral and non-viral HCC was assessed in 9 tumor samples by oligo-microarrays. The differentially expressed genes were examined using a z-score and KEGG pathway for the search of ontological biological processes. We selected a non-redundant set of 15 genes with the lowest P value for clustering samples into three groups using the non-supervised algorithm k-means. Fisher’s linear discriminant analysis was then applied in an exhaustive search of trios of genes that could be used to build classifiers for class distinction. Different transcriptional levels of genes were identified in HCC of different etiologies and from different HCC samples. When comparing HBV-HCC vs HCV-HCC, HBV-HCC/HCV-HCC vs non-viral (NV)-HCC, HBC-HCC vs NV-HCC, and HCV-HCC vs NV-HCC of the 58 non-redundant differentially expressed genes, only 6 genes (IKBKâ, CREBBP, WNT10B, PRDX6, ITGAV, and IFNAR1) were found to be associated with hepatic carcinogenesis. By combining trios, classifiers could be generated, which correctly classified 100 percent of the samples. This expression profiling may provide a useful tool for research into the pathophysiology of HCC. A detailed understanding of how these distinct genes are involved in molecular pathways is of fundamental importance to the development of effective HCC chemoprevention and treatment.


Assuntos
Humanos , Carcinoma Hepatocelular/genética , Perfilação da Expressão Gênica , Hepatite B/complicações , Hepatite C/complicações , Neoplasias Hepáticas/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Carcinoma Hepatocelular/virologia , Etiquetas de Sequências Expressas , Neoplasias Hepáticas/virologia , Biomarcadores Tumorais/genética
2.
Braz. j. med. biol. res ; 34(9): 1131-1138, Sept. 2001. ilus, tab
Artigo em Inglês | LILACS | ID: lil-290406

RESUMO

Parvovirus B19 has been associated by some investigators with cases of severe hepatitis. The aim of the present study was to determine the presence of active parvovirus B19 infection among 129 Brazilian patients with non-A-E hepatitis. The patients were assayed for antibodies against parvovirus B19, IgM class, by ELISA. In IgM-positive cases, parvovirus B19 DNA was assayed by PCR in serum and liver tissue and parvovirus VP1 antigen in liver tissue was assayed by immunohistochemistry. Antibodies against parvovirus B19, IgM class, were detected in 3 (2.3 percent) of 129 patients with non-A-E hepatitis. Previous surgery and blood transfusions were reported by these 3 patients. One patient was a 56-year-old female with severe hepatitis, with antimitochondrial antibody seropositivity and submassive necrosis at liver biopsy, who responded to corticosteroid therapy. Strong evidence for active parvovirus B19 infection was found in this patient, with parvovirus B19 DNA being detected by PCR in liver tissue. Furthermore, parvovirus VP1 antigen was also detected in liver tissue by immunohistochemistry. The other two IgM-positive patients were chronic hepatitis cases, but active infection was not proven, since neither viral DNA nor antigen were detected in their liver tissues. This and other reports suggest a possible relation between parvovirus B19 infection and some cases of hepatitis


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Hepatite Viral Humana/virologia , Parvovirus B19 Humano/isolamento & purificação , Doença Aguda , Anticorpos Antivirais/isolamento & purificação , Antígenos Virais/isolamento & purificação , Doença Crônica , DNA Viral/isolamento & purificação , Eletroforese em Gel de Ágar , Ensaio de Imunoadsorção Enzimática , Imunoglobulina M/isolamento & purificação , Fígado/patologia , Fígado/virologia , Parvovirus B19 Humano/imunologia , Reação em Cadeia da Polimerase
4.
Rev. Inst. Med. Trop. Säo Paulo ; 31(4): 235-41, jul.-ago. 1989. ilus
Artigo em Português | LILACS | ID: lil-98010

RESUMO

Acredtita-se que as lesöes teciduais na leptospirose possam decorrer da açäo direta das leptospiras, de toxinas sintetizadas ou liberadas durante sua lise. O presente estudo visou a extraçäo química da glicolipoproteína (GLP) da aleptospira, a produçäo de anti-soro anti-GLP e a avaliaçäo de sua distribuiçäo em cortes de fígado e rim de cobaias inoculadas e sacrificadas em estudo sequencial diário até o 6§ dia de infecçäo, correspondente ao pico da doença. Procurou-se também correlacionar a expressäo tecidual da GLP com o grau de lesöes locais, em busca de novos subsídios para a compreensäo da patogenia da leptospiros. A GLP foi detectada em fígado e rim de 2 dentre 6 cobaias no 5§ dia e em todas as 6 no 6§ dia de infecçäo, sob a forma de grânulos no citoplasma de macrófagos, livres no interstício ou acolados à membrana de células endoteliais e parenquimatosas, especialmente nas regiöes mais lesadas. A cronologia do aparecimento da GLP e sua distribuiçäo sugerem tratar-se de produto de lise de leptospiras fagocitadas por macrófagos e que esta substância, conquanto näo comprovada como iniciadora das lesöes, asocia-se a seu agravamento nas etapas mais avançadas da leptospirose


Assuntos
Animais , Cobaias , Doença de Weil/etiologia , Glicoproteínas/toxicidade , Leptospira interrogans/análise , Proteínas de Bactérias/toxicidade , Fígado/análise , Glicoproteínas/análise , Rim/análise , Proteínas de Bactérias/análise
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