Determinacion de la sensibilidad in vitro de diferentes cepas de Trypanosoma cruzi al benznidazol y al extracto de hoja de la planta Zanthoxylum chiloperone / Determination of the in vitro sensitivity of different Trypanosoma cruzi strains to benznidazole and the leaf extract of the plant Zanthoxylum chiloperone

Se evaluo la sensibilidad in vitro al benznidazol y al extracto de hojas de la planta Zanthoxylum chiloperone de diez cepas del Trypanosoma cruzi. Se utilizaron formas epimastigotas de las cepas, pertenecientes a diferentes linajes, diferente procedencia geografica, incluidas tres de Paraguay, y aisladas de hospederos distintos, abarcando humanos, triatominos y animales silvestres. El grado de sensibilidad a la droga y al extracto vegetal fue estimado por el porcentaje de lisis de los parasitos a las 24 y 48 horas de exposicion. Se observo un amplio rango de variacion en el porcentaje de lisis entre las cepas, de 22,2% a 90,8% a la concentracion del benznidazol de 200 ug/mL, con el hallazgo de una cepa con sensibilidad nula al mismo. Con respecto al extracto vegetal, tres concentraciones fueron testadas, de 500, 700 y 900 ug/mL, observandose variaciones en los porcentajes de lisis entre las cepas con las dos primeras concentraciones, entre un 2,1% y 100%, con lisis total en todas las cepas a la concentracion de 900 ug/mL. No se observo asociacion entre la diversidad de respuesta a los compuestos y la clasificacion de las cepas ni con su origen geografico y tipo de hospedero. Estas diferencias observadas resaltan la heterogeneidad de las poblaciones naturales del T. cruzi, aspecto importante a tener en cuenta en los estudios de sensibilidad a quimioterapeuticos y en los tamizajes primarios de nuevos antichagasicos. Asi mismo, se destaca la eficacia del extracto vegetal sobre diferentes cepas de este parasito.

Parasitoides de dípteros coletados em excrementos de animais no sul de Goiás / Parasitoids of dipterous collected in animal excrements in Southern Goiás, Brazil

This study determined the species of microhymenopterous of Diptera present in cattle and buffalo dung, from May 2003 to June 2004 and from April 2006 to March 2007 in chicken manure. All samples were collected in Southern Goiás State, Brazil. The dipterous pupae were obtained by the flotation method. They were individually placed in gelatin capsules until the emergence of the flies and/or their parasitoids. The percentages of parasitism in cattle dung and chicken manure were 12.4% and 10.0%, respectively.

Parasitóides de Diptera coletados em áreas florestal, rural e urbana em Monte Alegre, MG / Parasitoids of Diptera collected in forest, rural, and urban areas in Monte Alegre, MG

This study determined the species of parasitoids of Diptera present in forest, rural, and urban areas in the municipality of Monte Alegre, MG, from March to November 2006. The percentages of parasitism in forest, rural, and urban areas were 14.3 percent, 11.0 percent, and 18.8 percent, respectively. The most frequent species (34.7 percent) was Triplasta atrocoxalis (Ashmead) (Hymenoptera: Figitidae).

Influence of peri-domiciliar environmental conditions in the dispersion and proliferation of phlebotomine sandflies in Parana state, southern Brazil

The results of phlebotomine collections with Falcäo light traps are described. The collections were made in an area of the Mururê farm, in the Terra Boa County, Paraná State, south of Brazil. One trap was installed at the border of a modified primitive forest and seven in animal shelters (poultry sheds and pigsties) distant 10 to 600m from this forest. Of a total of 5,122 phlebotomine 4,046 (79 per cent) were caught in an pigsty 10m from the border of the forest. The dominant species was Lutzomya whitmani. Dispersion of phlebotomine was near to 600m from the border of the forest and suggests that good environmental conditions for effective breeding in peridomiciliary areas in Mururê farm were not found, what explains the rare occurrence of tegumentary leishmaniasis there