Ultrastructural study of the endocrine pancreas of the toad Bufo arenarum

The aim of the present report was to identify by electron microscopy the different endocrine cell types of the toad pancreas. Thus, we studied the pancreas from male specimens of Bufo arenarum with routine techniques for transmission electron microscopy. The results showed the presence of four endocrine cells types which would correspond to those responsible for the different pancreatic hormonal secretions in other species (B, A, D and PP cells). Type 1 cells contained rounded secretory granules with a clear halo which responded to two varieties: a) measuring 200 to 400 mm, and b) having a crystalloid core and a diameter of 400 to 600 nm; these cells would correspond to B cells showed rounded or irregular granules of 104 to 400 nm; they would be equivalent to A cells. Type 3 cells presented polymorphic ganules, most of them peanut-shaped, measuring 115 to 850 nm; they would resemble D cells. Finally, Type 4 cells contained rounded granules of 80 to 400 nm; these cells would correspond to PP cells. In addition, we also observed mixed cells exhibiting similar characteristics to acinar cells, but containing secretory granules resembling those found in some of the endocrine cell types; these would correspond to the acinar-islet cells reported in other animals. In conclusion, we described the ultrastructure of the toad endocrine pancreas and compare it with previous observations made in other amphibians.

Epidemiologia del latrodectismo en la Provincia de Buenos Aires, Argentina / Epidemiology of latrodectism in province of Buenos Aires, Argentina

Säo relatados os resultados do latrodecismo e seu tratamento específico durante um período de 10 anos (1979-1988), em Buenos Aires, Argentina. Säo evidenciados dados de distribuiçäo de acidentes por ano, meses, por sexo, residência do acidentado, regiäo corporal da picada, sintomas apresentados, tempo transcorrido entre o acidente e a aplicaçäo do soro antilatrodectus e a captura do animal agressor. Observou-se o pico entre 1982 a 1983 com 83 acidentes e uma média de 28,1 acidentes anuais, com maior índice de dezembro a março. Com respeito ao sexo e local de residência do acidentado, 80 por cento corresponde a homens, sendo principalmente trabalhadores rurais os mais afectados. A maior percentagem dos acidentes localizou-se no antebraço, cintura pélvica e coxa. Com respeito ao tempo transcorrido desde o acidente até a aplicaçäo do soro, 46 por cento foi realizado entre as três primeiras horas, sendo que foram capturados apenas 15 por cento dos animais agressores