Extracellular vesicles from oviductal isthmus and ampulla stimulate the induced acrosome reaction and signaling events associated with capacitation in bovine spermatozoa.

Cells can communicate with other neighboring or distant cells through the secretion of extracellular vesicles (EV), composed of a lipid bilayer and bearing surface molecules that allow them to recognize target cells. In this way, EV induce signaling via different mechanisms, modulating the physiological state of the recipient cell. EV have been identified in both male and female reproductive fluids, however, the possible role of EV isolated from female reproductive fluids has become an emerging field only recently. It is known that ejaculated mammalian spermatozoa need to undergo physiological preparation in the female reproductive tract to fertilize the egg. EV secreted by different regions of the female tract constitute signals that may have a key role in regulating sperm functions. The aims of the present study were isolating EV from different regions of the bovine oviduct and analyzing their interaction and physiological effects on spermatozoa. Here, we report the characterization of bovine oviductal fluid EV from the isthmus and ampulla region and their effect on the induced acrosome reaction and signaling events associated with sperm capacitation. EV induced an increase in sperm protein tyrosine phosphorylation, while cell survival of cryopreserved bovine spermatozoa was maintained. We also show that EV uptake regulates the sperm calcium levels by inducing an immediate increase in the intracellular calcium concentration and sperm priming, after a pre-incubation period, of the progesterone-induced intracellular calcium rise. Our data contribute to understand the role of EV in the communication between the female reproductive tract and the sperm physiology, information that may be used to improve the efficiency of reproductive assisted technologies.

Localización preoperatoria de lesiones no palpables de la mama utilizando aguja anzuelo metálico / Preoperative localization of the non palpable breast lesions with metalic needle

Presentamos 15 pacientes a las cuales se les realizó marcaje percutáneo preoperatorio de lesiones sospechosas de malignidad en la glándula mamaria, encontradas al realizar mastografía como estudio de escrutinio con la finalidad de que el cirujano practicase biopsia excisional de la lesión, no palpable; debido a su tamaño pequeño se utilizó la aguja anzuelo matálica, la cual se introdujo en forma perpendicular a la pared torácica al visualizar la mama de frente, dejando la punta del anzuelo en un diámetro de 5 mm de la lesión. Del total de las biopsias excisionales el 33 porciento fueron malignas y el resto de orígen benigno. Solo se tuvo como complicación una reacción vasovagal. El presente método de marcaje le permite al cirujano practicar la disección con mayor rapidez y precisión sin realizar cirugías extensas y es bien tolerado por las pacientes.