36 research outputs found
Ensaio quantitativo em tempo real para o DNA do vírus da hepatite B (HBV) desenvolvido para detectar todos os genótipos do HBV
Hepatitis B virus (HBV) is a major cause of chronic liver disease worldwide. Besides genotype, quantitative analysis of HBV infection is extensively used for monitoring disease progression and treatment. Affordable viral load monitoring is desirable in resource-limited settings and it has been already shown to be useful in developing countries for other viruses such as Hepatitis C virus (HCV) and HIV. In this paper, we describe the validation of a real-time PCR assay for HBV DNA quantification with TaqMan chemistry and MGB probes. Primers and probes were designed using an alignment of sequences from all HBV genotypes in order to equally amplify all of them. The assay is internally controlled and was standardized with an international HBV panel. Its efficacy was evaluated comparing the results with two other methods: Versant HBV DNA Assay 3.0 (bDNA, Siemens, NY, USA) and another real-time PCR from a reference laboratory. Intra-assay and inter-assay reproducibilities were determined and the mean of CV values obtained were 0.12 and 0.09, respectively. The assay was validated with a broad dynamic range and is efficient for amplifying all HBV genotypes, providing a good option to quantify HBV DNA as a routine procedure, with a cheap and reliable protocol.O vírus da Hepatite B (HBV) é uma das principais causas de doença crônica do fígado no mundo. Além do genótipo, a análise quantitativa do HBV é amplamente utilizada para monitorar a progressão da doença e o tratamento. Em locais com recursos escassos, métodos baratos para o monitoramento da carga viral são desejáveis e, em países em desenvolvimento, sua utilidade já foi demonstrada para outros vírus, como o da Hepatite C e HIV. Neste trabalho, descrevemos a validação de um teste de PCR em Tempo Real para a quantificação do DNA do HBV utilizando sondas Taqman/MGB. Os oligos e sondas foram escolhidos usando um alinhamento contendo seqüências de todos os genótipos do HBV para garantir uma amplificação igual de todos eles. O teste possui um controle interno e foi padronizado com um painel internacional de HBV. Sua eficácia foi testada comparando-se os resultados com outros dois métodos: Versant HBV DNA Assay 3.0 (bDNA, Siemens, NY, USA) e outro PCR em tempo real realizado em um laboratório de referência. As reprodutibilidades intra e inter-ensaio foram determinadas e a média dos valores de CV obtidos foram de 0,12 e 0,09, respectivamente. O teste foi validado com uma ampla faixa dinâmica e amplificou com eficiência os diferentes genótipos de HBV, fornecendo uma boa opção para a quantificação de rotina do DNA do HBV, com um protocolo barato e confiável
Translocation t(1;6)(p35;p25) in B-cell lymphoproliferative disorder with evolution to Diffuse Large B-cell Lymphoma
Case report of a translocation : Translocation t(1;6)(p35;p25) in B-cell lymphoproliferative disorder with evolution to Diffuse Large B-cell Lymphoma
A Novel Assay for the Identification of NOTCH1 PEST Domain Mutations in Chronic Lymphocytic Leukemia
Aims. To develop a fast and robust DNA-based assay to detect insertions and deletions mutations in exon 34 that encodes the PEST domain of NOTCH1 in order to evaluate patients with chronic lymphocytic leukemia (CLL). Methods. We designed a multiplexed allele-specific polymerase chain reaction (PCR) combined with a fragment analysis assay to detect specifically the mutation c.7544 7545delCT and possibly other insertions and deletions in exon 34 of NOTCH1. Results. We evaluated our assay in peripheral blood samples from two cohorts of patients with CLL. The frequency of NOTCH1 mutations was 8.4% in the first cohort of 71 unselected CLL patients. We then evaluated a second cohort of 26 CLL patients with known cytogenetic abnormalities that were enriched for patients with trisomy 12. NOTCH1 mutations were detected in 43.7% of the patients with trisomy 12. Conclusions. We have developed a fast and robust assay combining allele-specific PCR and fragment analysis able to detect NOTCH1 PEST domain insertions and deletions
Third Brazilian consensus for autoantibodies screening in HEp-2 cells (ANA) : recommendations for standardization of autoantibodies screening trial in HEp-2 cells, quality control and clinical associations
Objetivo: O 3º Consenso Brasileiro para pesquisa de autoanticorpos em Células HEp-2 (FAN) teve como propósito
avaliar as dificuldades de implantação do 2º Consenso ocorrido no ano de 2002, discutir estratégias para controlar a
qualidade do ensaio e promover a atualização das associações clínicas dos diversos padrões. Métodos: Participaram do
encontro em Goiânia nos dias 13 e 14 de abril de 2008 pesquisadores e especialistas de diversos centros universitários e
laboratórios clínicos de diferentes regiões do Brasil, com o propósito de discutir e aprovar as recomendações que visam à
melhor padronização, interpretação e utilização do ensaio pelos clínicos. Representantes comerciais de diferentes empresas
produtoras de insumos para realização do teste de FAN foram convidados como ouvintes. Resultados e Conclusões:
O 3º Consenso enfatizou a necessidade do controle de qualidade em imunofluorescência dada a heterogeneidade de
microscópios e reagentes disponíveis no mercado, promoveu adequações na terminologia utilizada para classificar os
diferentes padrões e, finalmente, atualizou as associações clínicas com finalidade de facilitar cada vez mais o melhor
uso do ensaio pelos clínicos. ________________________________________________________________________________ ABSTRACTObjective: The Third Brazilian Consensus for autoantibodies Screening in HEp-2 cells had as purpose the evaluation
of difficulties in the accomplishment of the 2nd Consensus recommendations that took place in the year of 2002, the
discussion of strategies for quality control of the assay and the promotion of an update of the clinical associations of
the several immunofluorescent patterns. Methods: Several ANA experts from university centers and private laboratories
in different areas in Brazil joined the workshop in Goiânia on 2008 April 13 and 14 with the purpose of discussing
and approving the recommendations for standardization, interpretation and use of the test by physicians. Commercial
representatives of different ANA slide brands were also invited as listeners to the workshop. Results and Conclusions:
The 3rd Consensus emphasized the need for quality control in indirect immunofluorescent since there is a considerable
heterogeneity of available microscopes and reagents. It also promoted adaptations in the previously approved terminology
used to classify the different patterns and finally updated the clinical associations of the several patterns with the
purpose of providing guidance for interpretation of the assay by clinical pathologists and assistant physicians
Third brazilian consensus for autoantIbodies screening in HEp-2 Cells : historical perspectve, quality control and clinical associatons
O III Consenso Brasileiro para Pesquisa de Autoanticorpos em Células HEp-2 (FAN) objetivou discutir
estratégias para controlar a qualidade do ensaio, promover a atualização das associações clínicas dos diversos
padrões e avaliar as difculdades de implantação do II Consenso ocorrido no ano de 2002. Métodos: Nos
dias 13 e 14 de abril de 2007 participaram do encontro em Goiânia pesquisadores e especialistas de diversos
centros universitários e laboratórios clínicos de diferentes regiões do Brasil, com o propósito de discutir e
aprovar as recomendações que visam a melhores padronização, interpretação e utilização do ensaio pelos
clínicos. Foram convidados como ouvintes representantes comerciais de diferentes empresas produtoras de
insumos para realização do teste de FAN. Resultados e conclusão: Dada a heterogeneidade de microscópios
e reagentes disponíveis no mercado, o III Consenso enfatizou a necessidade do controle de qualidade em
ensaios de imunofuorescência indireta. Foram também feitas algumas adequações na terminologia utilizada
para classifcar os diferentes padrões. Finalmente, foi realizada uma atualização das associações clínicas com
fnalidade de facilitar cada vez mais o melhor uso do ensaio pelos clínicos. _________________________________________________________________________________ ABSTRACTThe Third Brazilian Consensus for Autoantibodies Screening in HEp-2 Cells (ANA) had as purpose the
evaluation of diffculties in the accomplishment of the 2nd Consensus recommendations that took place in the
year of 2002, the discussion of strategies for quality control of the assay and the discussion of an update of the
clinical associations of the several immunofuorescent patterns. Methods: Several ANA experts from university
centers and private laboratories in different areas in Brazil joined the workshop in Goiânia on 2007 April 13
and 14 with the purpose of discussing and approving the recommendations for standardization, interpretation
and use of the test by physicians. Commercial representatives of different ANA slide brands were also invited as
listeners to the workshop. Results and conclusion: The 3rd ANA Consensus emphasized the need for quality
control in indirect immunofuorescent assays since there is a considerable heterogeneity of available microscopes
and reagents. It also promoted adaptations in the previously approved terminology used to classify the different
patterns and fnally updated the clinical associations of the several patterns with the purpose of providing
guidance for interpretation of the assay by clinical pathologists and assistant physicians
III Consenso Brasileiro para Pesquisa de Autoanticorpos em Células HEp-2: perspectiva histórica, controle de qualidade e associações clínicas
Negative Anti-C1q Antibody Titers May Influence Therapeutic Decisions and Reduce the Number of Renal Biopsies in Systemic Lupus Erythematosus
In a cross-sectional study involving 62 patients with systemic lupus erythematosus (SLE), we found that patients with biopsy-proven lupus nephritis (LN) had higher titers of anti-C1q antibodies than active SLE without nephritis patients. Anti-C1q was associated with a negative predictive value of 94.59%, a positive predictive value of 52%, a sensitivity of 86.66% and a specificity of 74.47% for the diagnosis of LN. We conclude that high titers of anti-C1q antibodies are strongly associated with the presence of active LN, and the negative predictive value of this test for diagnosing LN is very high; therefore, it can influence therapeutic decisions and reduce the number of renal biopsies in patients with SLE. Copyright (C) 2011 S. Karger AG, Base