ABSTRACT
The present study aimed to evaluate the frequency of KSHV genotypes isolated from Kaposi sarcoma (KS) lesions in patients from Brazil. Fifty KS cases were evaluated. The most frequently detected viral genotypes were A (50.0%) and C (48.0%); the B genotype was isolated only in one case (2.0%). Noteworthy, there was a significant predominance of A genotypes in KS lesions from HIV-positive patients, whereas C genotypes were found mostly in the HIV-negative setting. This finding supports the hypothesis that distinct KSHV genotypes have a non-random distribution in KS, which might be attributable to unique biological properties.
Subject(s)
HIV Infections/virology , Herpesvirus 8, Human/classification , Sarcoma, Kaposi/virology , Adolescent , Adult , Aged , Aged, 80 and over , Base Sequence , Brazil , Female , Genotype , Herpesvirus 8, Human/genetics , Humans , Male , Middle Aged , Molecular Sequence Data , Phylogeny , Young AdultABSTRACT
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.
Subject(s)
Epstein-Barr Virus Infections/genetics , Hodgkin Disease/genetics , Hodgkin Disease/virology , Interleukin-10/genetics , Polymorphism, Single Nucleotide/genetics , Promoter Regions, Genetic/genetics , Adolescent , Adult , Alleles , Case-Control Studies , Female , Genetic Predisposition to Disease/etiology , Genotype , Humans , Male , Middle Aged , Pseudolymphoma/geneticsABSTRACT
The Brazilian Agency for the Environment (IBAMA) recently adopted an alternative medium-term multiple-organ assay system with the Wistar rat strain for detection of the carcinogenic potential of pesticides. Originally, this initiation-promotion protocol was established in Japan with the isogenic Fischer 344 male rat. Among the initiating agents used in that assay, N-methyl-N-nitrosourea (MNU) rapidly induces malignant lymphoma and leukemia and early mortality of rats from different strains. This study was developed to evaluate whether the outbred Wistar rats are also similarly susceptible to MNU. Particularly, it aimed to evaluate the dose-response relationship and to register the MNU-induced pre-neoplasia and neoplasia that may develop in the lympho-hematopoietic system (LHS) of the Wistar rat within a medium-term period. Four groups of male Wistar rats were treated during 2 weeks with vehicle or with MNU (80, 160 or 240 mg/kg body weight, i.p.). After sacrifice at the 12th and 20th weeks, the thymus, spleen, bone marrow, cervical and mesenteric lymph nodes and liver were collected for analysis. At the 20th week, LHS malignant tumors and benign vascular tumors occurred only in the high- and intermediate-dose MNU-treated animals. Four animals treated with 240 mg/kg developed diffuse thymic lymphomas; two others, treated respectively with 240 mg/kg and 160 mg/kg, developed spleen hemangiomas. The present observations indicate that the Wistar strain is as susceptible as other strains to the early development of MNU-induced LHS (pre)neoplasia. Therefore, this strain seems suitable to be used as test system in bioassay protocols that adopt MNU as an initiating agent for carcinogenesis.
Subject(s)
Carcinogens/toxicity , Methylnitrosourea/toxicity , Precursor Cell Lymphoblastic Leukemia-Lymphoma/chemically induced , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Thymus Neoplasms/chemically induced , Thymus Neoplasms/pathology , Animals , Body Weight/drug effects , Bone Marrow/pathology , Male , Rats , Rats, Wistar , Spleen/drug effects , Spleen/pathologyABSTRACT
O linfoma da conjuntiva é bastante raro. Relatamos o caso de paciente portador de linfoma da conjuntiva do tipo linfócito difuso de pequenas células (de baixo grau de malignidade) e que apresentou vários aspectos incomuns desta patologia, tais como: bilateralidade, acometimento sistêmico simultâneo e entrópio palpebral
Subject(s)
Humans , Male , Aged , Conjunctival Neoplasms/diagnosis , Lymphoma/physiopathology , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosisABSTRACT
Paracoccidioidomicose é micose profunda causada pelo P. brasiliensis e caracterizada histologicamente por granulomas epitelióides, com supuraçäo central e halo linfomonoplasmocitário. O granuloma paracoccidioídico está intimamente relacionado com a resposta imune do hospedeiro. A infecçäo benigna, com resposta imune celular intacta, apresenta granulomas epitelóides compactos com poucos fungos; a infecçäo disseminada, anérgica, apresenta inflamaçäo granulomatosa frouxa, exsudativa, com numerosos fungos. No modelo endovenoso de paracoccidioidomicose experimental do camundongo, obtem-se infecçäo granulomatosa sistêmica, crônica e progressiva, envolvendo predominantemente os pulmöes e sistema retículo-endotelial. Os animais cursam com anticorpogênese específica elevada e depressäo da imunidade celular. Este modelo, por apresentar paralelismo histoimunológica com a doença humana, é útil para se estudar os mecanismos de defesa do hospedeiro envolvidos na morfogênese do granuloma paracoccidioídico. O presente trabalho teve como objetivos descrever a microanatomia do granuloma causado pelo P. brasiliensis em diferentes fases de sua evoluçäo e estabelecer correlaçöes entre o padräo de granuloma, o número de fungos e a resposta imune do hospedeiro. O delineamento experimental envolveu: i) a reproduçäo do modelo de paracoccidioidomicose murina por via endovenosa com a induçäo de doença sistêmica e progressiva; ii) o estudo evolutivo do padräo do granuloma causado pelo P. brasiliensis desde a fase inicial (2a. semana) até a fase avançada de infecçäo (16a. semana); iii) a caracterizaçäo por métodos histoquímicos e imunohistoquímicos com anticorpos monoclonais e policlonais, das subpopulaçöes linfocitárias T auxiliar e supressor, linfócitos B, histiócitos secretores (lisozima+), células apresentadoras de antígenos (S-100+), plasmócitos (IgG e IgM) e polimorfonucleares; iv) o estudo da distribuiçäo de antígenos de P. brasiliensis no granuloma, por método imunohistoquímico, utilizando anticorpo policlonal anti-P. brasiliensis; v) a avaliaçäo da resposta imune-nuclear pelo teste do coxim plantar e da imunidade humoral por ELISA. A maioria dos animais inoculados (87,5 por cento) apresentou lesöes pulmonares específicas, bilaterais. As lesöes granulomatosas pulmonares nas fases iniciais (2a.-4a. semana) caracterizaram-se por pequenos arranjos granulomatosos frouxos constituídos predominantemente por linfócitos T (35,4 por cento das células marcadas)...
Subject(s)
Animals , Male , Mice , Antigens/immunology , Granuloma/immunology , Granuloma/pathology , Paracoccidioidomycosis/immunology , Paracoccidioidomycosis/pathology , Antibodies, Monoclonal , Antibody Formation , Immunity, Cellular , Immunohistochemistry , Lymphocytes/immunologyABSTRACT
O presente trabalho compreende estudo anatomoclínico retrospectivo de 19 casos de crianças portadoras de rins policísticos e displasia renal (18 autópsias e uma biópsia); foram revistos os dados clínicos e a presença de malformaçöes e analisados os achados macro e microscópicos dos rins (classificaçäo de Potter). Os casos foram subdivididos segundo a distribuiçäo e freqüência das malformaçöes observadas, salientando-se a presença de dois grandes distintos sob o ponto de vista morfológico e patogenético: Grupo 1 (oito crianças), apresentando rins policísticos e displásicos (Tipos II e III) associados a malformaçöes sistêmicas múltiplas, ambos provavelmente conseqüentes a um mesmo agente agressor, atuante em diferentes fases da embriogênese e Grupo 2 (sete crianças), apresentando rins policísticos e displásicos (Tipo IV) associados a malformaçöes do trato urinário inferior. Postula-se neste grupo a açäo patogenética da obstruçäo e refluxo vesicoureteral na gênese da lesöes renais