Trypanosoma cruzi Strains and Autonomic Nervous System Pathology in Experimental Chagas Disease

Lesions involving the sympathetic (para-vertebral ganglia) and para-sympathetic ganglia of intestines (Auerbach plexus) and heart (right atrial ganglia) were comparatively analyzed in mice infected with either of three different strain types of Trypanosoma cruzi, during acute and chronic infection, in an attempt to understand the influence of parasite strain in causing autonomic nervous system pathology. Ganglionar involvement with neuronal destruction appeared related to inflammation, which most of the times extended from neighboring adipose and cardiac, smooth and striated muscular tissues. Intraganglionic parasitism was exceptional. Inflammation involving peripheral nervous tissue exhibited a focal character and its variability in the several groups examined appeared unpredictable. Although lesions were generally more severe with the Y strain, comparative qualitative study did not allow the conclusion, under the present experimental conditions, that one strain was more pathogenic to the autonomic nervous system than others. No special tropism of the parasites from any strain toward autonomic ganglia was disclosed

Trypanosoma cruzi strains and autonomic nervous system pathology in experimental Chagas disease.

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2012-10-19T19:46:33Z No. of bitstreams: 1 Souza MM Trypanosoma cruzi strains....pdf: 626348 bytes, checksum: fbb2680fb6d4d5acbd22444f56ba322f (MD5)Made available in DSpace on 2012-10-19T19:46:33Z (GMT). No. of bitstreams: 1 Souza MM Trypanosoma cruzi strains....pdf: 626348 bytes, checksum: fbb2680fb6d4d5acbd22444f56ba322f (MD5) Previous issue date: 1996Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilInstituto Adolfo Lutz. São Paulo, SP, BrasilInstituto Adolfo Lutz. São Paulo, SP, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilLesions involving the sympathetic (para-vertebral ganglia) and para-sympathetic ganglia of intestines (Auerbach plexus) and heart (right atrial ganglia) were comparatively analyzed in mice infected with either of three different strain types of Trypanosoma cruzi, during acute and chronic infection, in an attempt to understand the influence of parasite strain in causing autonomic nervous system pathology. Ganglionar involvement with neuronal destruction appeared related to inflammation, which most of the times extended from neighboring adipose and cardiac, smooth and striated muscular tissues. Intraganglionic parasitism was exceptional. Inflammation involving peripheral nervous tissue exhibited a focal character and its variability in the several groups examined appeared unpredictable. Although lesions were generally more severe with the Y strain, comparative qualitative study did not allow the conclusion, under the present experimental conditions, that one strain was more pathogenic to the autonomic nervous system than others. No special tropism of the parasites from any strain toward autonomic ganglia was disclosed

Controle de qualidade interlaboratorial em imuno-histoquímica: citoceratinas e receptor de estrógeno como modelos Interlaboratorial quality-control in immunohistochemistry: cytokeratins and estrogen receptors as models

INTRODUÇÃO: O grande incremento do uso da imuno-histoquímica (IHQ) em numerosos laboratórios de anatomia patológica amplia o poder de resolução diagnóstica, mas traz certo grau de heterogeneidade de procedimentos e resultados. Seguindo recentes propostas da literatura internacional, participantes do Clube de IHQ da Sociedade Brasileira de Patologia desenvolvem ações de controle de qualidade, aplicando protocolos de sua rotina à pesquisa de antígenos que sirvam como indicadores de qualidade da reação. MATERIAL E MÉTODO: Um total de dez laboratórios participou das duas etapas deste estudo, cujos marcadores foram pancitoceratinas e receptores de estrógeno. Com lâminas controle recebidas dos laboratórios, cada participante efetuou a técnica de IHQ conforme sua prática diária, retornando as lâminas juntamente com o formulário de procedimento. A avaliação semiquantificada de 0 a 4 da intensidade da reação específica e de 0 a 3 da coloração de fundo e da qualidade da técnica histológica foram atribuídas individual e sigilosamente durante a projeção em data show em reunião do Clube de IHQ, gerando um escore final. RESULTADOS E DISCUSSÃO: As variações na imunocoloração de citoceratinas e receptor de estrógeno não comprometeram sua detecção nas lâminas preparadas nos diversos laboratórios. Tais variações associaram-se à diversidade de sistemas de recuperação antigênica e de amplificação, resultando ora em imunopositividade menos intensa, ora em maior fundo. Outros estudos devem abordar questões de interpretação, incluindo-se critérios para semiquantificação.<br>BACKGROUND: The expansion of the use of immunohistochemistry (IHC) in numerous laboratories extends the power of diagnostic resolution, but may impart heterogeneity in procedures and results. Following recent international proposals, participants of the Club of IHC of the Brazilian Society of Pathology developed actions of quality control applying routine protocols for detection of some of the most relevant antigens as quality probes. OBJECTIVES: Ten laboratories participated on the present study on keratins and estrogen receptors. MATERIAL AND METHOD: On control-slides sent from each laboratory, each participant performed IHC reaction according to his daily practice, returning the slides with the filled procedure form. The evaluation of the intensity of the specific reaction and back-ground was performed individually during data show projection in a meeting of the Club of IHC, yielding a final score of performance. DISCUSSION AND CONCLUSION: The methodology adopted was found useful to ascribe the performance to the heterogeneous systems of antigenic retrieval and amplification, leading to the identification of moderate variation in intensity of immunoreaction and in back-ground, but not compromising the antigen detection in any of these laboratories. Other studies must approach interpretative questions, including semi-quantitation and cut-offs

Análise de indicadores internos e externos relevantes à resolutividade diagnóstica em laboratório de referência em imuno-histoquímica Analysis of internal and external factors potentially relevant to the diagnosis in immunohistochemistry in a public reference laboratory

OBJETIVO: Avaliar a resolutividade da imuno-histoquímica (IHQ) no diagnóstico de neoplasias em um laboratório de referência da rede de saúde pública e determinar potenciais influências da comunicação entre a fonte requisitante e o laboratório executante sobre tal resolutividade. MATERIAL E MÉTODOS: Mil casos oncológicos oriundos de oito hospitais públicos foram submetidos a exame IHQ, sendo 500 imediatamente anteriores e 500 posteriores à intervenção para aprimoramento da comunicação entre os requisitantes e o laboratório de IHQ. A recuperação de antígenos foi realizada pelo calor úmido sob pressão, e o sistema de detecção foi o LSAB plus System. Os resultados foram expressos como positivo, negativo ou inconclusivo. Foram coletadas informações sobre recebimento do bloco de parafina e fixador utilizado, guia de requisição de serviços de diagnóstico e terapia (SADT), laudo anatomopatológico original, topografia, idade e sexo do paciente. RESULTADOS E CONCLUSÃO: Foram coradas 5.719 lâminas pela IHQ de 989 casos considerados. A IHQ mostrou-se resolutiva em 919/989 (92,9%) casos. O número de antígenos por caso variou de um a 22, com média de 5,8 marcadores. A pesquisa de até cinco antígenos resolveu 534 casos e foram necessários até 10 marcadores para esclarecer 919 casos. Ainda hoje, informações básicas, como laudo anatomopatológico, idade e sexo do paciente, topografia, hipótese diagnóstica precisamente exposta, fixador e blocos de parafina em boas condições nem sempre são disponibilizadas aos laboratórios de referência. O aprimoramento dessa comunicação é essencial para a racionalização do fluxo dos exames IHQ e o incremento na qualidade da conclusão diagnóstica.<br>OBJECTIVES: The aim of this study was to evaluate the resolutivity of immunohistochemical (IHC) assays on neoplastic samples in a public health laboratory and to assess the influence of communication between the requiring institution and reference one on the quality of the IHC diagnosis. MATERIAL AND METHODS: One thousand oncological samples from eight public hospitals were submitted to IHC assay: 500 immediately before and 500 after an intervention demanding further information from the requiring pathologist. Antigen retrieval was performed in a pressure cooker and the detection system was LSAB plus System. The results were expressed as positive, negative or inconclusive. Information about paraffin blocks, fixatives, official requiring form, the attachment of original anatomopathological report, topography of the lesion, age and gender of the patients was collected. RESULTS AND CONCLUSION: From 989 samples, 5,719 slides were stained by IHC, leading to a resolutivity for 919/989 (92.9%). The number of antigen tested ranged from one to 22 - average of 5.8 for case. Panels with up to five antigens per case resolved 534 samples, whereas up to 10 markers were necessary to resolve 919 samples. Even nowadays, basic information, such as anatomopathological reports, age, gender, representative and technically superior paraffin block are not always available to the reference laboratory. The improvement of such communication is essential to rationalize the flux of immunohistochemical tests and to enhance the quality of diagnostic conclusions

Computer-assisted analysis of p53 and PCNA expression in oral lesions infected with human papillomavirus

OBJECTIVE: To carry out a retrospective study to determine whether human papillomavirus (HPV) infection and immunohistochemical expression of p53 and proliferating cell nuclear antigen (PCNA) are related to the risk of oral cancer. STUDY DESIGN: Fifty-seven oral biopsies, consisting of 30 oral squamous papillomas (OSPs) and 27 oral squamous cell carcinomas (OSCCs) were tested for the presence of HPV 6/11 and 16/18 by in situ hybridization using catalyzed signal amplification and in situ hybridization. p53 And PCNA expression was analyzed by immunohistochemistry and evaluated quantitatively by image analysis. RESULTS: Nineteen of the 57 oral lesions (33.3%) were positive for HPV. HPV 6/11 was found in 6 of 30 (20%) OSPs and 1 of 27 (3.7%) OSCCs. HPV 16/18 was found in 10 of 27 (37%) OSCCs and 2 of 30 (6.7%) OSPs. Sixteen of the 19 HPV-positive cases (84.2%) were p53 negative; 5 (9%) were HPV 6/11 and 11 (19%) HPV 16/18, with an inverse correlation between the presence of HPV DNA and p53 expression (P=.017, P < .05). PCNA expression appeared in 18 (94.7%) of HPV positive cases, showing that HPV 16/18 was associated with intensity of PCNA expression and with OSCCs (P=.037, P < .05). CONCLUSION: Quantitative evaluation of p53 by image analysis showed an inverse correlation between p53 expression and HPV presence, suggesting protein degradation. Image analysis also demonstrated that PCNA expression was more intense in HPV DNA 16/18 OSCCs. These findings suggest involvement of high-risk HPV types in oral carcinogenesis

Papilomavírus humano (HPV) em lesões benignas e malignas de mucosa oral pelos métodos de imuno-histoquímica e hibridização in situ

Fifteen oral biopsies with histopathological diagnosis of oral papilloma (n=7) and invasive squamous cell carcinoma (n=8) have been investigated for the presence of human papillomavirus (HPV) by immunohistochemistry (IHC) and in situ hybridization (ISH). HPV capsid proteins were evaluated by IHC (immunohistochemistry) with polyclonal antibody and the viral DNA analyzed by in situ hybridization with wide-spectrum, 6/11 and 16/18 biotinilated probes. HPV was detected by IHC in 13% (n=2) and, by ISH, in 60% (n=9) of the oral lesions. The two biopsies which immunostaned positive for HPV also exhibited HPV DNA 6/11. Moreover, HPV 16/18 was found in 20% of the oral carcinomas and 7% of the oral papillomas, while HPV 6/11 was detected in 7% of the carcinomas and 26% of the papillomas. It can be concluded that IHC is low efficient for the diagnosis of oral HPV and the presence of HPV 16/18 in benign and malignant lesions sugests the participation of this virus in oral carcinogenesis.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Molecular characterization of viruses associated with encephalitis in São Paulo, Brazil.

The objective of this study was to characterize the prevalence of viral encephalitis due to arbovirus infection of the Togaviridae and Flaviviridae families in São Paulo, Brazil. A total of 500 cerebrospinal fluid (CSF) samples collected between August 2012 and January 2013, from patients with symptoms of acute encephalitis were analyzed. Findings suggestive of viral encephalitis-elevations in cell concentration, glucose and total protein-were observed in 234 (46.8%) samples, designated as Group 1. The remaining 266 samples comprised Group 2. All samples were tested for Flaviviruses (dengue virus 1, 2, 3 and 4, yellow fever virus and West Nile virus), Alphavirus (NS5 region) and enterovirus by RT- PCR and for herpesviruses and enteroviruses using CLART-Entherpex. A presumptive viral etiological agent was detected in 26 samples (5.2%), 18 (8.0%) in Group 1 and 8 (3.0%) in Group 2. In Group 1 human herpesviruses were detected in 9 cases, enteroviruses in 7 cases, dengue viruses (DENV) in 2 CSFs and St. Louis encephalitis virus (SLEV) in one case. In Group 2 there were 3 CSFs positive for human herpesviruses, 2 for enteroviruses, 2 for DENV and 1 for SLEV. Detection of arboviruses, even though present in a minority of infected patients, identifies these viruses as a probable etiological agent of encephalitis. This is of special concern in regions where this class of viruses is endemic and has been linked to other recent epidemics