[Carotid-basilar artery communication in gerbils (Meriones unguiculatus)]. / Comunicación arterial carotidobasilar en gerbos (Meriones unguiculatus).

INTRODUCTION: Since 1966 when Levine and Payan observed that the Mongolian gerbil (Meriones unguiculatus) was unusually susceptible to cerebral infarction following occlusion of one or both common carotid arteries, the model has been used for the experimental study of cerebral ischemia. OBJECTIVE: To assess the presence of anterior-posterior arterial communication in the Mongolian gerbil (Meriones unguiculatus). MATERIAL AND METHODS: 26 animals were used and divided in the following groups: 1. Bilateral carotid ligation (n = 10); 2. Unilateral left carotid ligation (n = 5); 3. Unilateral carotid right carotid ligation (n = 5); and 4. Control group without carotid ligation (n = 6). RESULTS: Postmortem intra-aortic dye injection demonstrated communication between anterior and posterior cerebral arteries in 30% of gerbils that previously were subjected to bilateral common carotid artery occlusion. A number of vessels, between 8.95-11.35 microns in diameter, were linking the basilar artery with the posterior cerebral artery. In the remaining animals, the absence of communication was confirmed. CONCLUSION: Communicating carotid-basilar in lower number of cases and anastomosis the smallest diameter to give the gerbil advantage on others species as model of experimental regional ischemia.

Comunicación arterial carotidobasilar en gerbos (Meriones unguiculatus) / Carotid-basilar arterial communication in gerbils (Meriones unguiculatus)

Introducción. El modelo en gerbos para la investigación de la isquemia cerebral por oclusión bilateral y unilateral de la arteria carótida común ha sido empleado desde 1966, cuando Levine y Payan lo describieron como susceptible de desarrollar infarto cerebral y signos de daño neurológico por variantes de la circulación anastomótica cerebral. Objetivo. Demostrar la presencia de comunicaciones arteriales entre la circulación cerebral anterior y posterior. Material y métodos. La muestra la forman 26 gerbos que fueron anestesiados para exponer y ocluir las arterias carótidas comunes: 1. Grupo bilateral (n= 10); 2. Carótida izquierda (n= 5); 3. Carótida derecha (n= 5); 4. Sin oclusión (n= 6). Posteriormente se sacrificaron para perfusión intraórtica, inicialmente con solución salina (0,9 por ciento) y paraformaldehído (4 por ciento), y finalmente con colorantes para teñir las arterias. Los cerebros fueron extraídos 24 horas después y posfijados una semana más, para estudiar la circulación arterial cerebral, su distribución y la medición de diámetros de los vasos principales y secundarios, especialmente de los vasos terminales del tronco vertebrobasilar y de la arteria cerebral posterior. Resultados. Se encontró, en 30 por ciento de los animales con oclusión bilateral, pequeños vasos comunicantes posteriores de diámetro variable, entre 8,95 y 11,35 µm. En los restantes animales examinados no se encontró comunicación entre el sistema vertebrobasilar y el sistema carotídeo. Conclusión. La comunicación carotidobasilar, en menor número de casos y con anastomosis de diámetro pequeño, le dan al gerbo ventaja sobre otras especies como modelo de isquemia regional (AU)

Cola beverage consumption induces bone mineralization reduction in ovariectomized rats.

BACKGROUND: A significant association of cola beverage consumption and increased risk of bone fractures has been recently reported. The present study was carried out to examine the relationship of cola soft drink intake and bone mineral density in ovariectomized rats. METHODS: Study 1. Four groups of 10 female Sprague-Dawley rats were studied. Animals from groups II, III, and IV were bilaterally ovariectomized. Animals from groups I and II received tap water for drinking, while animals from groups III and IV each drank a different commercial brand of cola soft drink. After 2 months on these diets, the following were measured: solid diet and liquid consumption; bone mineral density; calcium in bone ashes; femoral cortex width; calcium; phosphate; albumin; creatinine; alkaline phosphatase; 25-OH hydroxyvitamin D, and PTH. RESULTS: Study 2. Two groups of seven ovariectomized rats were compared. Group A animals received the same management as the group III animals from study 1 (cola soft drink and rat chow ad libitum), while rats from group B received tap water for drinking and pair-feeding. After 2 months plasmatic ionized calcium, phosphate, creatinine, albumin, calcium in femoral ashes, and femoral cortex width were measured. Study 1. Rats consuming cola beverages (groups III and IV) had a threefold higher liquid intake than rats consuming water (groups I and II). Daily solid food intake of rats consuming cola soft drinks was one-half that of rats consuming water. Rats consuming soft drinks developed hypocalcemia and their femoral mineral density measured by DEXA was significantly lower than control animals as follows: group I, 0.20 +/- 0.02; group II, 0.18 +/- 0.01; group III, 0.16 +/- 0.01, and group IV, 0.16 +/- 0.01 g/cm(2). Study 2. To rule out the possibility that these calcium and bone mineral disorders were caused by decreased solid food intake, a pair-fed group was studied. Despite a lower body weight, pair-fed animals consuming tap water did not develop bone mineral reduction or hypocalcemia. CONCLUSIONS: These data suggest that heavy intake of cola soft drinks has the potential of reducing femoral mineral density.

Resultados de un nuevo procedimiento para evitar estenosis de la via biliar. / Results of a new procedure to avoid sstenosis of the bile duct

Las estenosis de los conductos biliares secundarias a seccion accidental, continuan siendo una complicacion quirurgica grave y dificil de solucionar, y se acompanan de un porcentaje alto de morbilidad y apreciable mortalidad. Con el proposito de establecer una metodologia para reducir o evitar estos problemas, se desarrollo un procedimiento experimental de anastomosis terminoterminal del coledoco normal seccionado, suspendida a una ferula circular semirrigida con caracteristicas especiales, colocada por fuera de la linea de union a manera de un anillo. Se obtuvo una union hermetica por coaptacion total de epitelio con epitelio, sin tension y con abertura maxima del conducto en la zona de reconstruccion. Durante la anastomosis tanto en el grupo de animales que se aplico este metodo como en el de control, se utilizaron instrumental y material de microcirugia y se descartaron la sonda T y el drenaje externo.En el grupo con protesis externa los resultados de los estudios radiologicos, macroscopicos e histologicos fueron excelentes, con ausencia de estenosis. De los animales de control, 50 por ciento presentaron estenosis parcial. No hubo mortalidad ni se produjeron fistulas

Microvascular stent.

Report of experimental results obtained with a new microvascular repair technique performed in the superficial femoral artery of the rat. An external device "microvascular stent" is used, made up medical use adhesive silicon so as to widen the internal vascular diameter and prevent stenosis. This technique is compare to the simple interrupted suture microsurgical repair.

[The presence of a red arch in the nail bed of a reimplanted hand and its prognostic value]. / Significado pronóstico del arco rojo en el lecho ungueal de las manos reimplantadas.

This is preliminary report describing a new clinical sign observed by the author in three cases of severed hands, and in several cases, following re-implantation within eight-hours after the accident. This sign has a useful prognostic value, based on its uniform and constant characteristics, in the evolution of re-implanted hands after severe trauma.