945 resultados para Benign Reactive Lymphoid Hyperplasia


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Known causes of conjunctival salmon patches include lymphoma, amyloidosis, sarcoidosis, leukaemia and benign reactive lymphoid hyperplasia. The aetiology of benign reactive lymphoid hyperplasia is thought to be a localized reactive change induced by an irritative or antigenic stimulus. The case of benign reactive lymphoid hyperplasia reported herein occurred in a myopic patient with extremely thin sclera. The authors' hypothesis is that choroidal antigens are able to perfuse through thin sclera and act as chronic irritants to the overlying conjunctiva resulting in a lymphoid response and subsequent salmon patch formation.

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A 30-basepair (bp) deletion in the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) gene has been reported in nasopharyngeal carcinoma and EBV-associated malignant lymphomas. Prior studies have found the deletion in about 10% to 28% of cases of Hodgkin's disease (HD), particularly in cases with aggressive histology. We studied the prevalence of 30-bp LMP1 gene deletion in EBV-positive HD in the United States (US) (12 cases) and Brazil (26 cases) with comparison to reactive lymphoid tissues (21 cases) and HD without EBV-positive Reed-Sternberg cells (15 cases). We studied the status of the LMP1 gene by Southern blot hybridization of polymerase chain reaction (PCR) products obtained after amplification with primers spanning the site of the deletion. We also performed EBV typing, EBER1 in situ hybridization, and LMP1 protein immunohistochemistry. EBV was detected in 12/26 (46%) cases of HD from the US and 26/27 (96%) cases of Brazilian HD. The 30-bp LMP1 gene deletion was observed in 4/12 (33%) cases of EBV-positive HD from US, and 12/26 (46%) cases of Brazilian EBV-positive HD, including 3 cases of type B EBV, as compared with 12/21 (57%) reactive lymphoid tissues and 9/15 (60%) cases of EBV-negative HD. US and Brazilian HD showed a higher prevalence of the 30-bp LMP1 gene deletion, compared with studies of others. The unexpected finding of high incidence of 30-bp deletion in LMP1 gene in reactive lymphoid tissue and HD without EBV-positive Reed-Sternberg cells suggests that this deletion may not be relevant to HD pathogenesis in most cases. Copyright (C) 1997 by W.B. Saunders Company.

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Context. - Hodgkin lymphoma is a neoplastic disease in which the immune system plays a major role in its pathogenesis. Interleukin 10 ( IL-10), an immunosuppressive cytokine actively produced in patients with Hodgkin lymphomas, favors the survival of the Hodgkin/Reed-Sternberg cells. Individual variations in IL-10 levels may be due, in part, to the presence of single nucleotide polymorphisms in the IL10 gene promoter.Objective. - To evaluate whether particular single nucleotide polymorphisms in the IL10 gene are found more frequently in Hodgkin lymphoma cases associated with Epstein-Barr virus infection.Design. - the identification of single nucleotide polymorphisms at positions -1082 and -819/-592 in the IL10 gene was performed by polymerase chain reaction and restriction length fragment polymorphisms analysis in 65 cases of Hodgkin lymphoma and 50 cases of reactive benign follicular lymphoid hyperplasia ( non-Hodgkin lymphoma control group).Results. - the frequency of the genotype GG at position -1082 was found to be significantly higher in patients with Epstein-Barr virus-positive Hodgkin lymphoma compared with Epstein-Barr virus-negative cases.Conclusions. - the results suggest that the presence of specific single nucleotide polymorphisms in the IL10 gene, notably those associated with high IL-10 production, may play a role in the susceptibility to Epstein-Barr virus -positive Hodgkin lymphoma development.

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Both Epstein-Barr virus (EBV) types A and B are found in endemic Burkitt's lymphoma (BL) occurring in equatorial Africa. We studied 17 cases of Brazilian BL previously demonstrated to be EBV-positive to determine the EBV type as well as the presence of a characteristic 30 bp deletion within the 3' end of the latent membrane protein-1 (LMP-1) gene that may be important to the pathogenesis of several EBV-associated neoplasms. All case in which the age was known were children. We found type A EBV in 13 of 14 (93%) evaluable cases, and type B in one case. The LMP-1 deletion was found in 12 of 15 (80%) evaluable cases, including the one case of type B EBV, and a similar high prevalence (59%) of the deletion was detected in EBV-positive normal and reactive lymphoid tissues from individuals from the same geographic region. The high proportion of cases associated with type A EBV suggests that immunodeficiency is not an important factor in the pathogenesis of Brazilian BL, in contrast to endemic African BL. The presence of the LMP-1 deletion in a high prevalence in the normal population in this region is unexplained.

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Background The utility of GATA3 as a marker for metastatic breast carcinoma in serous effusion specimens was investigated. Methods Cell block sections from 74 serous effusion specimens (32 ascitic, 2 pericardial and 40 pleural fluids) were stained with an anti-GATA3 murine monoclonal antibody. The specimens included 62 confirmed metastatic carcinomas from breast (30), female genital tract (13), gastrointestinal tract (7), lung adenocarcinoma (9), pancreas (1), kidney (1) and bladder (1). The breast carcinoma cases included 15 ductal carcinomas, 8 lobular carcinomas and in 7 the histology sub-type was not available. Twelve cases containing florid reactive mesothelial cells were also stained. The breast carcinoma cases were also stained for mammaglobin and GCDFP-15 to compare sensitivity with GATA3. Results Positive nuclear staining for GATA3 was present in 90% (27/30) of metastatic breast carcinoma specimens. All non-breast metastatic carcinomas tested were negative with the exception of the single case of metastatic urothelial carcinoma. No staining was observed in any of the benign reactive cases or in benign mesothelial cells present in the malignant cell block preparations. Two cases showed weak positivity of benign lymphoid cells. Staining results were unambiguous as all positive cases showed intense nuclear staining in >50% of tumor cells. Mammaglobin (57%; 17/30) and GCDFP-15 (33%; 10/30) were less sensitive markers of breast carcinoma. If used in a panel, mammaglobin and GCFP-15 staining would have identified only one additional case to those stained with GATA3. Conclusions GATA3 may be a useful addition to immunostaining panels for serous effusion specimens when metastatic breast carcinoma is a consideration.

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The present work evaluated histopathological aspects in experimental envenomation of dogs with Crotalus durissus terrificus venom. Twenty-eight mixed breed adult dogs were divided into three groups of seven animals each: Group I only venom; Group II - venom + 50ml antiophidic serum + fluid therapy; Group III venom + 50ml antiophidic serum + fluid therapy + urine alkalization. Lyophilized venom of Crotalus durissus terrificus was reconstituted in saline solution and inoculated subcutaneously at the dose of 1mg/kg body weight. Three animals of each group were subjected to euthanasia, and their muscular tissue, brain, spleen, kidneys, heart, lungs, stomach, small and large intestines, and popliteal lymph node fragments were collected for histopathological evaluation. There was myonecrosis in the inoculated limb, renal tubular degeneration, lymphoid hyperplasia of spleen, and unspecific reactive hepatitis. These results show the antigenicity and action of the venom on the immune system.

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

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Cutaneous reactive angiomatoses (CRA) encompass a distinct group of rare benign reactive vascular proliferations that include reactive angioendotheliomatosis, diffuse dermal angiomatosis and reactive intralymphatic histiocytosis. The etiology of these conditions, often associated with either localized or systemic diseases, is poorly understood. We report a 72-year-old woman who presented giant diffuse cellulitis-like plaques on the right lower limb and the pelvis and a reduction of her general condition with fever. Light microscopy studies revealed combined features of reactive angioendotheliomatosis, diffuse dermal angiomatosis and reactive intralymphatic histiocytosis. A small arteriovenous fistula of the right lower leg was thought to act as trigger. Systemic corticosteroids resulted in the clinical remission of the skin lesions. Our observation provides strong evidence that reactive angioendotheliomatosis, diffuse dermal angiomatosis and reactive intralymphatic histiocytosis, previously regarded as distinct forms of CRA, may show overlapping histopathological features and most likely represent facets of the same disease.

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L‟infection par le VIH-1, chez les patients, affecte principalement le système immunitaire et conduit à une destruction graduelle des lymphocytes T CD4 et, par conséquent, entraîne un état d‟immunodéficience. Cette immunodéficience permet l'établissement d‟infections opportunistes qui sont responsables de manifestations cliniques associées au Sida. Ces patients peuvent aussi développer des lymphomes, lésions du système nerveux central et une atteinte rénale. L'ampleur et la sévérité des conditions associées observées chez les patients infectés par le VIH-1 ne peuvent être imputées seulement au processus infectieux et à la déplétion des cellules T CD4+. Ceci suggère que les produits des gènes de régulation pourraient avoir des effets cytopathogènes. Cependant, les études sur la physiopathogenèse induite par le VIH ou ses différents gènes ont été difficiles à mener en raison de l'absence d'animaux de laboratoire infectés par ce virus. Ceux-ci auraient pu aider à disséquer le rôle des différents composants du génome viral et les mécanismes pathogénétiques impliqués. Pour pallier cette contrainte, nous avons produit le premier modèle de souris transgéniques pour le gène vpu. Vpu code pour une phosphoprotéine membranaire avec plusieurs fonctions connues. Elle participe au relargage des virions à la surface cellulaire, induit la dégradation des CD4, induit la régulation négative des CMH-1, augmente la susceptibilité à la mort cellulaire des lymphocytes T infectés par le VIH et favorise la réplication virale en empêchant les mécanismes antiviraux cellulaires. Dans ce travail, nous avons caractérisé pathologiquement un modèle de souris transgéniques porteuses du gène vpu du VIH-1. Nos résultats démontrent que l‟expression de vpu chez les souris transgéniques induit le développement spontané d‟une hyperplasie lymphoïde pansystémique, une splénomégalie avec une hyperplasie lymphoïde folliculaire évoluant en lésions prémalignes et malignes qui présentent certaines similarités avec la maladie de Castleman et une iv glomérulonéphrite mesangioproliférative qui rappelle certaines altérations de néphropathie associée au VIH chez les patients infectés. L‟ensemble des altérations démontre que les souris Tg/vpu développent une activation chronique et non spécifique du système immunitaire. Dans cette activation immunitaire, une dérégulation de l‟IL-6 et une hyperplasie du réseau de cellules métallophiliques pourraient être impliquées. D‟autres résultats obtenus sur les évaluations du fonctionnement du système immunitaire de la rate et du thymus mettent en évidence une susceptibilité augmentée des lymphocytes des tissus lymphoïdes aux effets apoptotiques de la dexaméthasone et des lipopolysaccharides et un retard dans le repeuplement par les cellules d‟organes lymphoïdes ainsi qu‟une réaction inflammatoire (Schwartzman) exacerbée et des anomalies dans la réaction d‟hypersensibilité retardée expérimentale. Ce modèle transgénique reproduit plusieurs anomalies rencontrées chez les patients infectés par le VIH et ouvre de nouvelles hypothèses sur la pathogenèse de l‟infection par le VIH.

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O presente estudo acompanhou durante 82 dias o curso da infecção experimental com T. evansi em quatro cães, realizando a avaliação dos achados hematológicos, bioquímicos e anatomopatológicos. Os animais infectados mostraram declínio acentuado na contagem de hemácias, hematócrito e teor de hemoglobina, permanecendo anêmicos a partir da terceira semana de infecção até o final do período experimental. Leucopenia com neutropenia foram observadas entre a segunda e a quinta semanas após a infecção. Os cães inoculados desenvolveram hiperproteinemia, sendo constatada diminuição na relação albumina:globulina. As atividades séricas de alamina aminotransferase e aspartato aminotransferase aumentaram significativamente nos cães infectados em relação aos animais controle. O exame histopatológico revelou hiperplasia linfóide no baço e linfonodos e infiltrado mononuclear periportal e esteatose de padrão centrolobular no fígado de todos os cães infectados. Intenso infiltrado mononuclear foi observado no miocárdio de três cães e acúmulos de células mononucleares junto às meninges foram evidenciados em dois animais infectados.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The association between parasitic infection of the appendix and acute appendicitis has been widely investigated. The aim of this retrospective study was to evaluate the prevalence of parasitic infection of the appendix in a tropical area at southeast Brazil and to assess its possible relation to acute appendicitis in surgically removed appendices. of the 1,600 appendectomies performed during a 10-year period, 24 (1.5%) were found to have helminths within the appendix. Enterobius vermicularis was observed in 23 of the 24 specimens (95.8%), and Taenia sp. was detected in only one case. Sixteen patients (66.7%) were less than 10 years old; 15 patients were male and nine female; 21 patients were white, and three were nonwhites. Pathologic analysis disclosed acute neutrophilic inflammation in the appendix wall in 12 of the 24 specimens and lymphoid hyperplasia in 10 of the 24 appendices. Gangrenous appendicitis was diagnosed in three cases, and peritonitis was found in 11 of the 24 infected appendices. The results of the present study indicate that E. vermicularis is the commonest worm found in the appendix and that its presence can cause pathologic changes ranging from lymphoid hyperplasia to acute phlegmonous inflammation with life-threatening complications like gangrene and peritonitis.