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1.
Histopathology ; 48(4): 377-86, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16487359

RESUMEN

AIMS: To report nine additional well-defined cases with infiltrative myelopathy by paracoccidioidomycosis (PCM), to describe the specific lesions and infection-related stromal abnormalities, to review the literature on this type of involvement and to introduce a new cause of granulomatous lesions of bone marrow. METHODS AND RESULTS: Different bone marrow specimens were studied (aspirated smears, aspirated clots, biopsy imprints and biopsies) from nine patients with acute or subacute forms of PCM known to have PCM infiltrative myelopathy. CONCLUSIONS: The biopsy specimens were the best for demonstrating bone marrow involvement by PCM. The lesions varied from compact and focal granulomas with few fungal cells to numerous disseminated fungal cells within a loose granulomatous inflammatory reaction, with a continuum between these extremes suggesting a spectrum of immune response to the fungi. Other findings such as bone marrow fibrosis, parenchymal coagulative necrosis and bone necrosis were also observed in the affected areas.


Asunto(s)
Enfermedades de la Médula Ósea/patología , Médula Ósea/patología , Paracoccidioidomicosis/complicaciones , Adolescente , Adulto , Biopsia , Enfermedades de la Médula Ósea/etiología , Examen de la Médula Ósea , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad
2.
Environ Monit Assess ; 102(1-3): 349-57, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15869195

RESUMEN

The Atlantic Forest with its exuberant vegetation of high level of biodiversity is classified as one hotspot of the world. Chemical composition of leaves from native trees and underlying soils was evaluated by INAA. The predominant species Euterpe edulis, Bathysa meridionalis, Hyeronima alchorneoides, Marlierea tomentosa, Gomidesia flagellaris, and Gomidesia spectabilis belonging to the diverse plant families were studied. Euterpe edulis, the most abundant understory specie, presented the lowest element concentrations except for Zn. Some variation in chemical composition was noted, however, the chemical specificity of tree species can be more predominant than the soil variability for the obtained leaf concentrations. Factor values obtained through the Monte-Carlo assisted factor analysis were used for species discrimination, The results indicate that chemical investigation of native trees is a quite promising tool for biodiversity studies in the Atlantic Forest.


Asunto(s)
Metales/análisis , Contaminantes del Suelo/análisis , Árboles/química , Biodiversidad , Brasil , Monitoreo del Ambiente/estadística & datos numéricos , Análisis Factorial , Método de Montecarlo , Hojas de la Planta/química
3.
Braz J Med Biol Res ; 37(11): 1707-12, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15517087

RESUMEN

Epstein-Barr virus (EBV) is a ubiquitous herpesvirus, and most people have serological evidence of previous viral infection at adult age. EBV is associated with infectious mononucleosis and human cancers, including some lymphomas and gastric carcinomas. Although EBV was first reported in lymphoepithelioma-like gastric carcinoma, the virus was also found in conventional adenocarcinomas. In the present study, 53 gastric carcinomas diagnosed in São Paulo State, Brazil, were evaluated for EBV infection by non-isotopic in situ hybridization with a biotinylated probe (Biotin-AGACACCGTCCTCACCACCC GGGACTTGTA) directed to the viral transcript EBER-I, which is actively expressed in EBV latently infected cells. EBV infection was found in 6 of 53 (11.32%) gastric carcinomas, mostly from male patients (66.7%), with a mean age of 59 years old. Most EBV-positive tumors were in gastric antrum. Two EBV-positive tumors (33.3%) were conventional adenocarcinomas, whereas four (66.7%) were classified as lymphoepithelioma-like carcinomas. EBV infection in gastric carcinomas was reported elsewhere in frequencies that range from 5.6% (Korea) up to 18% (Germany). In Brazil, a previous work found EBV infection in 4 of 80 (5%) gastric carcinomas, whereas another study found 4.7 and 11.2% of EBV-positive gastric carcinomas of Brazilians of Japanese origin or not, respectively. In the present study, the frequency of EBV-positive gastric carcinomas is similar to that reported in other series, and the clinicopathologic characteristics of these EBV-positive tumors are in agreement with the data in the literature.


Asunto(s)
Adenocarcinoma/virología , Infecciones por Virus de Epstein-Barr/diagnóstico , Herpesvirus Humano 4/aislamiento & purificación , Neoplasias Gástricas/virología , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Infecciones por Virus de Epstein-Barr/patología , Femenino , Humanos , Hibridación in Situ , Masculino , Persona de Mediana Edad , ARN Viral/análisis , Neoplasias Gástricas/patología
4.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;37(11): 1707-1712, Nov. 2004. ilus, tab
Artículo en Inglés | LILACS | ID: lil-385872

RESUMEN

Epstein-Barr virus (EBV) is a ubiquitous herpesvirus, and most people have serological evidence of previous viral infection at adult age. EBV is associated with infectious mononucleosis and human cancers, including some lymphomas and gastric carcinomas. Although EBV was first reported in lymphoepithelioma-like gastric carcinoma, the virus was also found in conventional adenocarcinomas. In the present study, 53 gastric carcinomas diagnosed in São Paulo State, Brazil, were evaluated for EBV infection by non-isotopic in situ hybridization with a biotinylated probe (Biotin-AGACACCGTCCTCACCACCC GGGACTTGTA) directed to the viral transcript EBER-I, which is actively expressed in EBV latently infected cells. EBV infection was found in 6 of 53 (11.32 percent) gastric carcinomas, mostly from male patients (66.7 percent), with a mean age of 59 years old. Most EBV-positive tumors were in gastric antrum. Two EBV-positive tumors (33.3 percent) were conventional adenocarcinomas, whereas four (66.7 percent) were classified as lymphoepithelioma-like carcinomas. EBV infection in gastric carcinomas was reported elsewhere in frequencies that range from 5.6 percent (Korea) up to 18 percent (Germany). In Brazil, a previous work found EBV infection in 4 of 80 (5 percent) gastric carcinomas, whereas another study found 4.7 and 11.2 percent of EBV-positive gastric carcinomas of Brazilians of Japanese origin or not, respectively. In the present study, the frequency of EBV-positive gastric carcinomas is similar to that reported in other series, and the clinicopathologic characteristics of these EBV-positive tumors are in agreement with the data in the literature.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adenocarcinoma/virología , Infecciones por Virus de Epstein-Barr/diagnóstico , /aislamiento & purificación , Neoplasias Gástricas/virología , Adenocarcinoma/patología , Brasil , Infecciones por Virus de Epstein-Barr/patología , Hibridación in Situ , ARN Viral/análisis , Neoplasias Gástricas/patología
5.
Blood ; 94(1): 244-50, 1999 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10381519

RESUMEN

We examined the types of Epstein-Barr virus-associated nuclear antigen-1 (EBNA-1) gene carboxy (C)-terminal mutations occurring in Hodgkin's disease (HD) and reactive tissues from two different geographic regions. Previously reported EBNA-1 C-terminal region amino acid sequence variants, based on the amino acid at codon 487, include Prototype (P)-ala, which is found in the B95.8-derived prototype virus, P-thr, Variant (V)-leu, V-val, and V-pro. Using polymerase chain reaction (PCR) to amplify portions of the EBNA-1 gene, followed by DNA sequencing, we found a single EBNA-1 gene sequence variant in each tissue, whether reactive or neoplastic and whether from Brazil or the United States. Variant EBNA-1 gene sequences were more common in both neoplastic and non-neoplastic tissues from different geographic areas than the so-called prototype sequence. In the 17 Brazilian HD cases, 4 cases had P-thr variants and 13 had V-leu variants. In the six reactive tissues from Brazil, one had a P-ala variant, two had P-thr variants, and three had V-leu variants. In the 12 American HD cases, 2 had P-ala variants, 6 had P-thr variants, and 4 had V-leu variants. The 11 American reactive tissues included 2 P-ala variants, 5 P-thr variants, and 4 V-leu variants. In both countries, there were similar variant EBNA-1 sequences present in normal tissues and HD cases. Compared with the P-ala and P-thr cases, the V-leu cases were more likely to have the 30-bp latent membrane protein 1 (LMP1) gene deletion (P = 0.0075). In addition, cases of HD with the V-leu were statistically associated with a substitution of asparagine for glutamine at codon 322 of the C-terminal portion of the LMP1 gene. Our results suggest that any variation in EBNA-1 gene sequence is caused by a polymorphism present in pre-existing viral strains in the underlying population, and not a mutation occurring during oncogenesis.


Asunto(s)
Antígenos Nucleares del Virus de Epstein-Barr/genética , Genes Virales , Enfermedad de Hodgkin/genética , Brasil , Eliminación de Gen , Enfermedad de Hodgkin/virología , Humanos , Polimorfismo Genético , Análisis de Secuencia de ADN , Estados Unidos
6.
Mycopathologia ; 141(2): 79-91, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9750339

RESUMEN

Adult Swiss (susceptible) and BALB/c (non-susceptible) mice were inoculated by the intravenous route with 1 x 10(6) yeast cells of Paracoccidioides brasiliensis, strain 18. Immunologic parameters, histopathology and features of the bronchoalveolar lavage (BAL) were evaluated at week 2, 4, 8 and 16 post-infection. The pulmonary infection was progressive in Swiss mice and regressive in Balb/c mice. The numbers of total cells, lymphocytes and polymorphonuclear neutrophils increased in BAL, as well as the percentages of giant cells, and CD4 and CD8 positive cells. The ultrastructural study of BAL cells revealed a predominance of macrophages and a frequency of 13.2% of type II pneumocytes. As the infection progressed, the number of fungal cells and spreading macrophages, as well as the stimulated release of H2O2 by macrophages, increased. The animals exhibited an exacerbation of the humoral immune response and a depression of cellular immunity during the infection. There was a good correlation between the intensity and the pattern of the pulmonary histopathology and the cellular findings in the BAL. The present model reproduces some anatomoclinical patterns of the human disease and shows that BAL may be a useful tool in monitoring the pulmonary infection caused by P. brasiliensis.


Asunto(s)
Líquido del Lavado Bronquioalveolar/citología , Enfermedades Pulmonares Fúngicas/patología , Pulmón/patología , Paracoccidioidomicosis/patología , Animales , Anticuerpos Antifúngicos/sangre , Líquido del Lavado Bronquioalveolar/inmunología , Líquido del Lavado Bronquioalveolar/microbiología , Recuento de Células , Ensayo de Inmunoadsorción Enzimática , Peróxido de Hidrógeno/metabolismo , Hipersensibilidad Tardía , Inmunidad Innata , Inmunodifusión , Pulmón/inmunología , Pulmón/microbiología , Enfermedades Pulmonares Fúngicas/inmunología , Enfermedades Pulmonares Fúngicas/microbiología , Macrófagos Alveolares/fisiología , Macrófagos Alveolares/ultraestructura , Masculino , Ratones , Ratones Endogámicos BALB C , Paracoccidioides/inmunología , Paracoccidioides/aislamiento & purificación , Paracoccidioidomicosis/inmunología , Paracoccidioidomicosis/microbiología , Subgrupos de Linfocitos T
7.
Rev. bras. neurol ; 34(4): 135-7, jul.-ago. 1998. ilus
Artículo en Portugués | LILACS | ID: lil-229525

RESUMEN

A síndrome de Garcin é rara. O objetivo deste trabalho é descrever um caso relacionado a linfoma näo-Hodgkin. Um paciente de 41 anos desenvolveu comprometimento sucessivo de múltiplos nervos cranianos. Do lado direito havia alteraçöes de todos os nervos cranianos, caracterizando a síndrome de Garcin. Exérese de linfonodo revelou linfoma näo-Hodgkin de grandes células, e observou-se infiltraçäo difusa da medula óssea. O líquido cefalorraquiano mostrou pleocitose com 100 por cento de imunoblastos. A tomografia computadorizada de crânio näo revelou massas. Esta é a primeira descriçäo clínica da síndrome de Garcin completa causada por infiltraçäo linfomatosa difusa dos nervos cranianos


Asunto(s)
Humanos , Masculino , Adulto , Nervios Craneales/patología , Linfoma no Hodgkin , Líquido Cefalorraquídeo , Tomografía Computarizada por Rayos X
8.
Am J Pathol ; 152(1): 191-8, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9422536

RESUMEN

A 30-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. Information on this deletion in EBV-associated gastric carcinoma (EBVaGC) is limited. The association of gastric carcinoma (GC) with EBV was examined by EBV-encoded RNA (EBER) in situ hybridization in 510 patients from Japan and 80 patients from Brazil. We studied the prevalence of 30-bp LMP1 gene deletion in EBVaGC in Japan (29 cases) and Brazil (four cases) in comparison with the corresponding EBER1-positive metastatic lesions in lymph nodes (10 cases) and EBV-infected reactive lymphocytes from dissected nonmetastatic lymph nodes (22 cases), microdissected non-neoplastic gastric mucosa of EBVaGC (five cases), and EBV-nonassociated GC (25 cases). We studied the status of the LMP1 gene by Southern blot hybridization of polymerase chain reaction products obtained after amplification with primers flanking the site of the deletion. We also performed EBV typing and LMP1 protein immunohistochemistry. EBV DNA was amplified by polymerase chain reaction in 30 of 33 EBVaGC cases, 8 of 10 metastatic carcinomas, 14 non-neoplastic tissues from 27 EBVaGC cases, and 12 of 25 non-EBV-associated GC cases with EBER1-positive lymphocytes. The 30-bp LMP1 gene deletion was observed in 23 of 26 (88.5%) cases of EBVaGC from Japan and two of four (50%) cases of Brazilian EBVaGC as compared with EBER1-positive reactive lymphocytes from 11 of 14 (78.6%) EBVaGC cases and 9 of 12 (75%) cases of non-EBV-associated GC. The variant type (the 30-bp deletion variant or nondeleted wild type) of LMP1 gene was the same among reactive lymphocytes, primary and secondary lesions of EBVaGC in all cases for which all three tissue types were studied (six of six). There was no correlation between the presence of the 30-bp deletion with depth of cancer invasion or presence of metastasis. Type A was detected in all available EBV-positive cases. The similar high incidence of 30-bp deletion in LMP1 gene in both carcinoma cells and reactive lymphocytes in EBVaGC cases suggests that this deletion may not be relevant to the pathogenesis of EBVaGC.


Asunto(s)
Carcinoma/virología , Eliminación de Gen , Herpesvirus Humano 4/genética , Metástasis Linfática/genética , Linfocitos/virología , Neoplasias Gástricas/virología , Proteínas de la Matriz Viral/genética , Adulto , Anciano , Anciano de 80 o más Años , Brasil/etnología , Carcinoma/etnología , Carcinoma/genética , Femenino , Humanos , Hibridación in Situ , Japón/etnología , Linfocitos/fisiología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Neoplasias Gástricas/etnología , Neoplasias Gástricas/genética
9.
Revista Brasileira de Neurologia ; 4(34): 135-137, jul./ago. 1998.
Artículo | Index Psicología - Revistas | ID: psi-7370

RESUMEN

A sindrome de Garcin e rara. O objetivo deste trabalho e descrever um caso relacionado a linfoma nao-Hodgkin. Um paciente de 41 anos desenvolveu comprometimento sucessivo de multiplos nervos cranianos. Do lado direito havia alteracoes de todos os nervos cranianos, caracterizando a sindrome de Garcin. Exerese de linfonodo revelou linfoma nao-Hodgkin de grandes celulas, e observou-se infiltracao difusa da medula ossea. O liquido cefalorraquiano mostrou pleocitose com 100 por cento de imunoblastos. A tomografia computarizada de cranio nao revelou massas. Esta e a primeira descricao clinica de sindrome de Garcin completa causada por infiltracao linfomatosa difusa dos nervos cranianos.


Asunto(s)
Nervios Craneales , Linfoma no Hodgkin , Neoplasias de los Nervios Craneales , Nervios Craneales , Linfoma no Hodgkin
10.
Hum Pathol ; 28(12): 1408-14, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9416698

RESUMEN

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.


Asunto(s)
Frecuencia de los Genes , Herpesvirus Humano 4/genética , Enfermedad de Hodgkin/genética , Enfermedad de Hodgkin/patología , Tejido Linfoide/patología , Eliminación de Secuencia , Proteínas de la Matriz Viral/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Composición de Base , Brasil/epidemiología , Cápside/genética , Femenino , Enfermedad de Hodgkin/epidemiología , Enfermedad de Hodgkin/virología , Humanos , Tejido Linfoide/virología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Estados Unidos/epidemiología , Latencia del Virus/genética
11.
Am J Clin Pathol ; 105(2): 230-7, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8607450

RESUMEN

The occurrence of malignant lymphoma is an increasingly important cause of morbidity and mortality in AIDS patients. The incidence of AIDS-related lymphoma in some developing countries such as Brazil is increasing as the survival of HIV infection has improved. Although there is a clear association between several types of immunodeficiency-related lymphomas and Epstein-Barr virus (EBV), the association of EBV infection in AIDS-related lymphoma in Brazil, where the incidence of AIDS is high, is unknown. Formalin-fixed, paraffin-embedded tissue from 24 cases of AIDS-related lymphoma in Brazil were analyzed for morphologic classification, immunophenotype, and EBV association using in situ hybridization studies with an EBV-EBER1 biotinylated probe. Twenty cases of AIDS-related lymphoma were classified as non-Hodgkin's lymphoma and four cases were Hodgkin's disease. Eleven non-Hodgkin's lymphomas were classified as diffuse large cell type, five cases were small non-cleaved cell, Burkitt-type, and four cases were large cell immunoblastic non-Hodgkin's lymphoma. Eighteen cases were of B-cell phenotype; one was a T-cell lymphoma, and one was classified as null. Epstein-Barr virus (EBV) was demonstrated in the majority of tumor cells of 11 of 20 (55%) of the cases non-Hodgkin's lymphomas and in 3 of 4 (75%) cases of Hodgkin's disease. AIDS-related lymphomas in Brazil are usually of large cell/immunoblastic type, but Hodgkin's disease is also seen. Both non-Hodgkin's lymphoma and Hodgkin's disease are often associated with EBV infection. The non-Hodgkin's lymphoma is predominantly of B-cell phenotype.


PIP: While there is a clear association between several types of immunodeficiency-related lymphomas and Epstein-Barr virus (EBV), the association of EBV infection in AIDS-related lymphoma in Brazil, where the incidence of AIDS is high, has remained unknown. The authors report their findings from an analysis of tissue samples from 24 cases of AIDS-related lymphoma in Brazil. The samples were analyzed for morphologic classification, immunophenotype, and EBV association. 20 cases were classified as non-Hodgkin's lymphoma, while 4 were Hodgkin's disease. 11 non-Hodgkin's lymphomas were classified as diffuse large cell type, 5 as small, non-cleaved cell, Burkitt-type, and 4 as large cell immunoblastic non-Hodgkin's lymphoma. 18 cases were of B-cell phenotype; one was a T-cell lymphoma and one was classified as null. EBV was demonstrated in the tumor cells of 11 of the 20 non-Hodgkin's lymphoma cases and in 3 of the 4 cases of non-Hodgkin's disease.


Asunto(s)
Infecciones por Herpesviridae/complicaciones , Herpesvirus Humano 4/aislamiento & purificación , Linfoma Relacionado con SIDA/patología , Linfoma Relacionado con SIDA/virología , Infecciones Tumorales por Virus/complicaciones , Adulto , Brasil , Femenino , Infecciones por Herpesviridae/virología , Enfermedad de Hodgkin/inmunología , Enfermedad de Hodgkin/patología , Enfermedad de Hodgkin/virología , Homosexualidad Masculina , Humanos , Inmunofenotipificación , Hibridación in Situ , Ganglios Linfáticos/patología , Linfoma Relacionado con SIDA/genética , Linfoma Relacionado con SIDA/inmunología , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células B Grandes Difuso/virología , Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/patología , Linfoma no Hodgkin/virología , Masculino , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/virología , ARN Viral/análisis , Trastornos Relacionados con Sustancias , Infecciones Tumorales por Virus/virología
12.
Mod Pathol ; 9(1): 63-7, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8821959

RESUMEN

The incidence of Burkitt's lymphoma (BL) in Brazil is intermediate between the endemic form of equatorial Africa and the sporadic form in the United States. To characterize these lymphomas, we evaluated the clinical, morphologic, and immunohistochemical features of 24 Brazilian cases of BL. We also analyzed the cases for the presence of Epstein-Barr virus (EBV)-RNA using a highly sensitive and specific method of in situ hybridization. Most cases presented with involvement of intraabdominal organs, similar to the sporadic form of BL. EBV-RNA was detected in 17 of 24 cases (71%) in all or virtually all the tumor cells. This prevalence of EBV-positivity in our cases is intermediate between the endemic form of BL in equatorial Africa (100%) and the sporadic form in the United States (30%). These findings suggest that EBV plays an important role in the pathogenesis of BL in Brazil. This intermediate incidence of EBV infection may explain in part the differences of incidence of BL in different geographic regions.


Asunto(s)
Linfoma de Burkitt/epidemiología , Linfoma de Burkitt/virología , Herpesvirus Humano 4/aislamiento & purificación , Adolescente , Adulto , Brasil/epidemiología , Linfoma de Burkitt/patología , Niño , Preescolar , Femenino , Herpesvirus Humano 4/genética , Humanos , Inmunohistoquímica , Hibridación in Situ , Masculino , ARN Viral/genética
13.
Am J Pathol ; 148(1): 17-23, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8546204

RESUMEN

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 cases 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.


Asunto(s)
Linfoma de Burkitt/virología , Herpesvirus Humano 4/clasificación , Adolescente , Secuencia de Bases , Brasil/epidemiología , Linfoma de Burkitt/epidemiología , Niño , Femenino , Eliminación de Gen , Genes Virales/genética , Genotipo , Herpesvirus Humano 4/genética , Humanos , Tejido Linfoide/virología , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa
14.
Mycopathologia ; 130(3): 131-40, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7566066

RESUMEN

The effect of macrophage blockade on the natural resistance and on the adaptative immune response of susceptible (B10.D2/oSn) and resistant (A/Sn) mice to Paracoccidioides brasiliensis infection was investigated. B10.D2/oSn and A/Sn mice previously injected with colloidal carbon were infected ip with yeast cells to determine the 50% lethal dose, and to evaluate the anatomy and histopathology, macrophage activation, antibody production and DTH reactions. Macrophage blockade rendered both resistant and susceptible mice considerably more susceptible to infection, as evidenced by increased mortality and many disseminated lesions. P. brasiliensis infection and/or carbon treatment increased the ability of macrophages from resistant mice to spread up to 25 days after treatment. In susceptible mice the enhanced spreading capacity induced by carbon treatment was impaired at all assayed periods except at 1 week after infection. Macrophage blockade enhanced DTH reactions in resistant mice, but did not alter these reactions in susceptible mice, which remained anergic. To the contrary, macrophage blockade enhanced specific antibody production by susceptible mice, but did not affect the low levels produced by resistant mice. The effect of macrophage blockade confirms the natural tendency of resistant animals to mount DTH reactions in the course of the disease and the preferential antibody response developed by susceptible mice after P. brasiliensis infection. On the whole, macrophage functions appear to play a fundamental role in the natural and acquired resistance mechanisms to P. brasiliensis infection.


Asunto(s)
Macrófagos Peritoneales/inmunología , Paracoccidioidomicosis/inmunología , Animales , Anticuerpos Antifúngicos/sangre , Carbono/farmacología , Movimiento Celular/efectos de los fármacos , Coloides/farmacología , Susceptibilidad a Enfermedades , Femenino , Hipersensibilidad Tardía , Inmunidad Innata , Inmunoglobulina G/sangre , Dosificación Letal Mediana , Activación de Macrófagos , Ratones , Ratones Endogámicos , Paracoccidioides/inmunología , Paracoccidioides/patogenicidad , Paracoccidioidomicosis/patología
15.
Braz J Med Biol Res ; 27(12): 2803-20, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7550001

RESUMEN

1. Immunocytochemical procedures have played an increasingly larger role in the identification of infectious disease agents in tissue sections owing to the increased availability and specificity of antibody reagents, the great sensitivity of the methods, and the relative facility with which the studies are performed. 2. Immunocytochemical methods can be applied to routine formalin-fixed tissue for the detection of infectious agents such as viruses, bacteria, fungi, and protozoa among other microorganisms for diagnostic and research purposes.


Asunto(s)
Enfermedades Transmisibles/diagnóstico , Inmunohistoquímica/métodos , Serodiagnóstico del SIDA , Cardiomiopatía Chagásica/diagnóstico , Enfermedades Transmisibles/etiología , Infecciones por Citomegalovirus/diagnóstico , Encefalitis Viral/diagnóstico , Infecciones por Helicobacter/diagnóstico , Hepatitis B/diagnóstico , Hepatitis Crónica/diagnóstico , Humanos , Paracoccidioidomicosis/diagnóstico
16.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;27(12): 2803-20, Dec. 1994. ilus
Artículo en Inglés | LILACS | ID: lil-153280

RESUMEN

1. Immunocytochemical procedures have played an increasingly larger role in the identification of infectious disease agents in tissue sections owing to the increased availability and specificity of antibody reagents, the great sensitivity of the methods, and the relative facility with which the studies are performed. 2. Immunocytochemical methods can be applied to routine formalin-fixed tissue for the detection of infectious agents such as viruses, bacteria, fungi, and protozoa among other microorganisms for diagnostic and research purposes


Asunto(s)
Enfermedades Transmisibles/diagnóstico , Técnicas para Inmunoenzimas , Técnicas In Vitro , Serodiagnóstico del SIDA , Infecciones por Citomegalovirus/diagnóstico , Enfermedades Transmisibles/etiología , Encefalitis Viral/diagnóstico , Hepatitis B/diagnóstico , Hepatitis Crónica/diagnóstico , Infecciones por Helicobacter/diagnóstico , Cardiomiopatía Chagásica/diagnóstico , Paracoccidioidomicosis/diagnóstico
17.
Mycopathologia ; 126(3): 137-46, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7935728

RESUMEN

The specific delayed-type hypersensitivity (DTH) response was evaluated in resistant (A/SN) and susceptible (B10.A) mice intraperitoneally infected with yeasts from a virulent (Pb18) or from a non-virulent (Pb265) Paracoccidioides brasiliensis isolates. Both strains of mice were footpad challenged with homologous antigens. Pb18 infected A/SN mice developed an evident and persistent DTH response late in the course of the disease (90th day on) whereas B10.A animals mounted a discrete and ephemeral DTH response at the 14th day post-infection. A/SN mice infected with Pb265 developed cellular immune responses whereas B10.A mice were almost always anergic. Histological analysis of the footpads of infected mice at 48 hours after challenge showed a mixed infiltrate consisting of predominantly mononuclear cells. Previous infection of resistant and susceptible mice with Pb18 did not alter their DTH responses against heterologous unrelated antigens (sheep red blood cells and dinitrofluorobenzene) indicating that the observed cellular anergy was antigen-specific. When fungal related antigens (candidin and histoplasmin) were tested in resistant mice, absence of cross-reactivity was noted. Thus, specific DTH responses against P. brasiliensis depend on both the host's genetically determined resistance and the virulence of the fungal isolate.


Asunto(s)
Hipersensibilidad Tardía , Paracoccidioidomicosis/inmunología , Animales , Antígenos Fúngicos , Reacciones Cruzadas , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos A , Paracoccidioides/inmunología , Paracoccidioides/patogenicidad , Paracoccidioidomicosis/patología , Virulencia/inmunología
18.
J Med Microbiol ; 40(3): 159-64, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8114064

RESUMEN

The interaction of human monocytes or monocyte-derived macrophages and yeast-form Paracoccidioides brasiliensis was studied in vitro. Yeast cells were readily ingested by adherent monocytes or macrophages. Multiplication of P. brasiliensis, measured by growth as colony forming units (cfu) on a supplemented medium with good plating efficiency, was greater in monocyte co-cultures compared to the number of cfu obtained from complete tissue-culture medium (CTCM). Multiplication increased with time in macrophage co-cultures, e.g., from two-six-fold in 24 h to nine-fold in 72 h. Microscopic observations indicated that ingested yeast cells multiplied inside macrophages. When monocytes were treated with supernate cytokines (CK) from concanavalin-A-stimulated mononuclear cells, then co-cultured with P. brasiliensis, multiplication was significantly inhibited compared with control monocyte co-cultures. Treatment of macrophages--derived from monocytes by culture in vitro for 3 days--for a further 3 days with CK resulted in maximal inhibition of multiplication over the subsequent 72 h. Similarly, when monocyte-derived macrophages (after culture for 7 days) were treated for 3 days with recombinant human gamma-interferon (IFN; 300 U/ml) or CK they restricted multiplication of P. brasiliensis by 65% and 95%, respectively, compared with control macrophages. Antibody to IFN abrogated the effect of IFN or CK treatment. These findings show that ingested P. brasiliensis can multiply in human monocytes or macrophages and that this multiplication can be restricted by activated monocytes or macrophages.


Asunto(s)
Citocinas/inmunología , Macrófagos/microbiología , Monocitos/microbiología , Paracoccidioides/crecimiento & desarrollo , Fagocitos/microbiología , Adulto , Adhesión Celular , Células Cultivadas , Recuento de Colonia Microbiana , Medios de Cultivo , Humanos , Interferón gamma/inmunología , Linfocitos/microbiología , Activación de Macrófagos , Macrófagos/inmunología , Monocitos/inmunología , Paracoccidioides/inmunología , Fagocitos/inmunología , Fagocitosis , Proteínas Recombinantes
19.
Biol Trace Elem Res ; 43-45: 643-8, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7710882

RESUMEN

Scandium and ash methods' performances were compared in terms of soil content assessment in sugar cane loads, emphasizing the common sampling drawbacks. Both methods are adequate for such determination in controlled conditions. The scandium has demonstrated better analytical characteristics, since it is free from interferences of cane matrix, which decreases the accuracy of the ash method in normal mill conditions.


Asunto(s)
Carbohidratos/análisis , Industria de Procesamiento de Alimentos/normas , Escandio/análisis , Suelo/análisis , Brasil , Fibras de la Dieta/análisis , Incineración , Minerales/análisis , Análisis de Activación de Neutrones , Control de Calidad , Sesgo de Selección
20.
Biol Trace Elem Res ; 43-45: 663-8, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7710885

RESUMEN

The effectiveness of industrial washing operation in minimizing soil in sugar cane delivered to mills is evaluated. Instrumental neutron activation analysis was the nuclear analytical technique chosen for this work, with Fe, Hf, Sc, and Th selected as soil tracers. On the basis of differences between elemental concentration of integral and prepared cane, that is before and after washing, the feasibility of the method for evaluation of the washing efficiency is demonstrated.


Asunto(s)
Carbohidratos/análisis , Contaminación de Alimentos/análisis , Industria de Procesamiento de Alimentos/normas , Brasil , Análisis de Activación de Neutrones , Suelo/análisis , Oligoelementos/análisis
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