Ultrastructure of ovarian follicular epithelium of the Amazonian fish Pseudotylosurus microps (Teleostei: Belonidae): morphological and histochemical characterization of the intercellular deposits

The present paper reports the presence of great quantities of electrondense intercellular material in the follicular epithelium of P. microps. The material apparently is uptaken from circulation and enter the follicle through the intercellular spaces accumulating in the epithelial median-apical intercellular spaces and in perioocytic space. The accumulation starts in the early growth of the primary oocyte and proceed until vitellogenesis. The possible chemical nature and function of the deposits are discussed

Apoptosis en trofoblasto de pacientes con aborto espontáneo recurrente de causa no identificada / Apoptosis in trophoblast of patients with recurrent spontaneous abortion of non identified cause

El aborto espontáneo recurrente de causa no identificada o idiopático es un importante problema de salud reproductiva. En este trabajo se ha iniciado el estudio de uno de los mecanismos que podrían mediar en esta patología del embarazo humano, La hipótesis general que se propone, es que en los casos de pacientes con aborto espontáneo recurrente de causa no identificada (AER), existen fenómenos en el entorno materno/feto/placentario que se manifiestan en daño en la funcionalidad y/o vitalidad del tejido placentario. La hipótesis planteada fue consistente con el hallazgo de activación masiva de muerte celular programada en todos los casos con AER estudiados en este trabajo.

Scanning electron microscopy of the eggs of Mansonia uniformis, Ma. indiana and Ma. annulifera (Diptera: Culicidae).

Descriptions of the eggs of Mansonia uniformis, Ma. indiana and Ma. annulifera are provided with the aid of scanning electron micrographs. Eggs of these three species, although similar in shape and colour, are covered by outer chorionic reticulum and tubercles which provide reliable morphological character for their identification. Size, distribution and number of lobes on the large tubercles present in the region between the anterior tube and posterior region, are important distinguishing features. Measurements of egg sizes and other chorionic differences are also discussed.