To assess the histologic changes produced by platinum microcoils with an inner core of cross-link... more To assess the histologic changes produced by platinum microcoils with an inner core of cross-linked bovine collagen in experimentally induced aneurysms in swine, and to assess the feasibility of the system for the delivery of the collagen. METHODS: Bilateral pouch aneurysms were created in the side wall of the common carotid artery in seven barnyard pigs. Eight aneurysms were treated with coils designed with an interlocking detachment mechanism: in four of these, the coils had an inner core of collagen; in the other four, the platinum microcoils had a similar design but without the collagen mandrel. The packing density of the coils within the aneurysm was approximately the same for both types of coils. The other six aneurysms were left untreated and served as controls. Angiograms were obtained at the time of treatment (2 weeks after the aneurysms were created) and at 1, 4, and 8 weeks after treatment. All animals were killed 8 weeks after the treatment (10 weeks after the aneurysms were created). Arteries and aneurysms were resected en bloc and fixed for histopathologic study. RESULTS: The interlocking detachment mechanism worked well. Little difference was noted between the two types of coils in their ability to effect complete aneurysmal thrombosis (three of four aneurysms treated with collagen-core coils and two of four aneurysms treated with conventional coils). The collagen-core coils stimulated new collagen formation in areas proximal to the coils, and more fibroblasts were noted near the collagencore coils than near the conventional coils. CONCLUSION: Local fibroblast proliferation and collagen production were stimulated by heterologous cross-linked collagen embedded in microcoils in this experimental model. Such biologic stimulation holds promise for improving the endovascular cure rate of aneurysms in humans.
En esta revisión se presenta un recorrido sobre el proceso de la evolución cerebral en los último... more En esta revisión se presenta un recorrido sobre el proceso de la evolución cerebral en los últimos 4 millones de años; en la segunda parte, se enfatiza en el concepto de modularidad de la mente, y el papel del lenguaje y de la fluidez cognitiva en el paso de la mente primitiva a la mente moderna. Se hace referencia a las funciones ejecutivas, la memoria de trabajo y la teoría de la mente. El enfoque es el de la teoría de la complejidad, la cual concibe la mente como una emergencia, es decir, como una propiedad de la interacción, en este caso, de la interacción neural presente en el cerebro.
To assess the histologic changes produced by platinum microcoils with an inner core of cross-link... more To assess the histologic changes produced by platinum microcoils with an inner core of cross-linked bovine collagen in experimentally induced aneurysms in swine, and to assess the feasibility of the system for the delivery of the collagen. METHODS: Bilateral pouch aneurysms were created in the side wall of the common carotid artery in seven barnyard pigs. Eight aneurysms were treated with coils designed with an interlocking detachment mechanism: in four of these, the coils had an inner core of collagen; in the other four, the platinum microcoils had a similar design but without the collagen mandrel. The packing density of the coils within the aneurysm was approximately the same for both types of coils. The other six aneurysms were left untreated and served as controls. Angiograms were obtained at the time of treatment (2 weeks after the aneurysms were created) and at 1, 4, and 8 weeks after treatment. All animals were killed 8 weeks after the treatment (10 weeks after the aneurysms were created). Arteries and aneurysms were resected en bloc and fixed for histopathologic study. RESULTS: The interlocking detachment mechanism worked well. Little difference was noted between the two types of coils in their ability to effect complete aneurysmal thrombosis (three of four aneurysms treated with collagen-core coils and two of four aneurysms treated with conventional coils). The collagen-core coils stimulated new collagen formation in areas proximal to the coils, and more fibroblasts were noted near the collagencore coils than near the conventional coils. CONCLUSION: Local fibroblast proliferation and collagen production were stimulated by heterologous cross-linked collagen embedded in microcoils in this experimental model. Such biologic stimulation holds promise for improving the endovascular cure rate of aneurysms in humans.
En esta revisión se presenta un recorrido sobre el proceso de la evolución cerebral en los último... more En esta revisión se presenta un recorrido sobre el proceso de la evolución cerebral en los últimos 4 millones de años; en la segunda parte, se enfatiza en el concepto de modularidad de la mente, y el papel del lenguaje y de la fluidez cognitiva en el paso de la mente primitiva a la mente moderna. Se hace referencia a las funciones ejecutivas, la memoria de trabajo y la teoría de la mente. El enfoque es el de la teoría de la complejidad, la cual concibe la mente como una emergencia, es decir, como una propiedad de la interacción, en este caso, de la interacción neural presente en el cerebro.
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