Resumen Objetivos: Identificar las alteraciones histopatológicas en órganos de ratas Wistar para evaluar los efectos tóxicos del uso del Extracto de Hoja Cruda de Annona muricata (AMRLE) solo o en asociación con DMBA. Configuración y diseño: Se utilizaron sesenta ratas hembras Wistar, se separaron en grupos y se trataron con una dosis única de 65 mg/kg de DMBA y/o con 50, 100 y 200 mg/kg de AMRLE. Se utilizaron tinciones de hematoxilina-eosina (HE) y azul de metileno al 1% en el análisis histopatológico y la cuantificación de criptas aberrantes (CA) y focus de criptas aberrantes (FCA). En el análisis estadístico se utilizaron las pruebas de Fischer y Kruskal Wallis. Resultados: La administración de 65 mg/kg de DMBA y/o 50, 100 y 200 mg/kg de AMRLE no influyó en el desarrollo del peso. Se observaron algunas alteraciones histopatológicas (esteatosis hepática; focus inflamatórios en el hígado, riñón y pulmón; hiperplasia, ectasia en epitelio de la glándula mamaria e hiperplasia linfoide pulmonar) y el desarrollo de CA y FCA en el colon intestinal en todos los grupos, excepto en el grupo control negativo, sin diferencias estadísticas entre los grupos analizados. Conclusiones: Las alteraciones histopatológicas y la formación de CA y FCA no mostraron diferencias estadísticamente significativas entre los grupos analizados. Sin embargo, aunque AMRLE tiene efectos antioxidantes debido a la presencia de componentes fenólicos, aún existe la formación de algunos procesos patológicos que pueden estar relacionados con la acción tóxica aislada del DMBA y/o asociados con otros componentes de AMRLE, ya que estos cambios no fueron observados en el grupo control negativo.

Abstract Aims: To identify the histopathological alterations in organs of Wistar rats to evaluate toxic effects of use of Annonamuricata Raw Leaf Extract (AMRLE) alone or in association with DMBA. Settings and Design: Sixty female Wistar rats were used, separated into groups and treated with a single dose of 65 mg/kg of DMBA and/or with 50; 100 and 200 mg/kg of AMRLE. Hematoxylin-Eosin (HE) and 1% methylene blue stains were used in the histopathological analysis and quantification of Aberrant Crypts (ACs) and Aberrant Crypt Focus (ACF). Fischer and Kruskal Wallis tests were used in the statistical analysis. Results: The administration of 65 mg/kg of DMBA and/or 50, 100 and 200 mg/kg of AMRLE did not influence weight development. Some histopathological alterations (hepatic steatosis; inflammatory foci in the liver, kidney and lung; pulmonary lymphoid hyperplasia, ectasia and hyperplasia in mammary gland epithelium) and the development of ACs and ACF in the intestinal colon were observed in all groups, except in the group negative control, with no statistical difference between analysed groups. Conclusions: Histopathological alterations and the formation of ACs and ACF did not show a statistically significant difference between the groups analysed. However, although AMRLE has antioxidant effects due to the presence of phenolic components, there was still the formation of some pathological processes that may be related to the isolated toxic action of DMBA and/or associated with other components of AMRLE, since these changes were not seen in the negative control group.

Pouco é sabido sobre o potencial patogênico de Blastocystis sp. em modelos experimentais. Neste trabalho a patogenicidade desse parasito para o trato gastrointestinal de camundongos Swiss machos foi avaliada de acordo com o inóculo e tempo de infecção. Os animais foram infectados, via intragástrica, com 100, 500, 1.000, 5.000 e 10.000 formas vacuolares de Blastocystis sp. obtidos a partir de uma mistura de oito isolados humanos cultivados axenicamente em meio Jones. Após 7, 14, 21, 28 e 60 dias de infecção os animais foram sacrificados e fragmentos do intestino delgado (duodeno), grosso e ceco foram retirados para análise histopatológica. Blastocystis sp. desencadeou resposta inflamatória nos diferentes tecidos analisados, com predominância de infiltrado mononuclear. No ceco o parasito foi encontrado na túnica muscular mostrando seu caráter invasivo. Inóculos maiores desencadearam processos inflamatórios mais precocemente (7 dias) e inóculos menores mais tardiamente (a partir de 21 dias). Conclui-se que no modelo proposto a patogenicidade dos isolados de Blastocystis sp. estudados tem relação com o inóculo e tempo de infecção.

The pathogenic potential of Blastocystis sp. in experimental models requires further investigation. In this work, the pathogenicity of this parasite in the gastrointestinal tract of male Swiss mice was evaluated according to the inoculum size and period of infection. Animals were infected intragastrically, with 100, 500, 1,000, 5,000 and 10,000 Blastocystis sp. vacuolar forms obtained from a mixture of eight human isolates cultured axenically in Jones' medium. After seven, 14, 21, 28 and 60 days of infection, the animals were sacrificed and fragments of the small intestine (duodenum), large intestine, and cecum were subjected to histopathological analysis. Blastocystis sp. triggered an inflammatory response in the different tissues analyzed, with a predominance of mononuclear cells. The parasite was found in the muscular layer of the cecum, showing its invasive character. Larger inocula triggered inflammatory processes earlier (seven days) than smaller ones (from 21 days). We conclude that, in the proposed model, the pathogenicity of Blastocystis sp. isolates that were studied is related to inoculum size and period of infection.

Isolados de Fusarium graminearum, obtidos de espigas de trigo com sintomas de Giberela, foram analisados pela técnica do Polimorfismo de DNA Amplificado ao Acaso (RAPD) e pelos Grupos de Compatibilidade Vegetativa (GCV). Mutantes auxotróficos (nit) de cada isolado foram pareados em todas as combinações possíveis, para a formação de heterocários. Três GCVs foram identificados: GCV1, incluindo os isolados F-2, F-3 e F-4; GCV2, incluindo os isolados F-1, F-6 e F-9; e GCV3, formado pelos isolados F-5, F-7 e F-8. Dois grupos foram identificados com base nos marcadores de RAPD: o grupo A, formado pelos isolados F-2 e F-9, e o grupo B, composto pelos demais isolados, os quais apresentaram grande similaridade entre si. Os resultados sugerem a origem clonal dos isolados de F. graminearum analisados.

Fusarium graminearum isolates causing Fusarium head blight in wheat were collected in Brazil and analyzed by random amplified polymorphic DNA (RAPD) markers and vegetative compatibility grouping (VCG). Nitrate non-utilizing mutants (nit) from each isolate were paired to verify heterokaryon formation. Three VCGs were identified among F. graminearum isolates: VCG1 included F-2, F-3 and F-4 isolates; VCG2 included F-1, F-6 and F-9 isolates; VCG3 included F-5, F-7 and F-8 isolates. Based on PCR amplification with eight different primers, the isolates showed great genetic similarity among themselves. Dendrogram analysis demonstrated two RAPD groups: Group A, consisting of isolates F-2 and F-9, and Group B, composed of the remaining isolates. Results suggest the clonal origin of F. graminearum isolates.