Leptomeningeal cysts after spot freezing: transmission and scanning electron microscopic observations.

The sequential development of the early phases of leptomeningeal cyst formation was studied in an experimental model. Light, transmission and scanning electron microscopic data were compared with those from human arachnoid cysts. Common features observed were: the participation of leptomeningeal cells in the structure of the cysts with exclusion of dural components; the absence of internal traversing trabeculae; the hyperplasia of leptomeningeal cells, particularly in the dome of the cysts.

Solitary abscess in rat brain: light and electron microscopy observations.

The authors describe the histological and ultrastructural features of a well demarcated single abscess. Histopathological features are consistent with those observed in experimental models and human material. In addition this study allowed the ultrastructural definition of some of the capsule components as meningothelial-like structures and myofibroblasts.

On the pathogenesis and therapy of dementia of the Alzheimer type: some neuropathological, biochemical, genetic and pharmacotherapeutic considerations.

The extensive literature on dementia of Alzheimer type (DAT) testifies to the enormous progress achieved in the clinical and biochemical delineation of this disease. Newly developed laboratory and imaging techniques are also being applied to the diagnosis of DAT. Nevertheless, unequivoval diagnosis still relies primarily on morphological data from biopsy or autopsy.

The fate of human umbilical vein grafts as an infrarenal aortic substitute in monkeys.

The literature contains conflicting reports about the potential value of the processed human umbilical vein graft as an arterial substitute. With a view to a better understanding of the ultimate fate of this device, a series of long-term implantation was undertaken with a nonhuman primate model. Dardik Biografts were implanted as an infrarenal aortic substitute in 13 monkeys.

[Pathology of cerebral edema. II. Experimental models and modifying agents].

Current experimental models of brain edema are described and evaluated for their contribution to the knowledge of basic processes involved in its production as well their contribution to the understanding of different clinical forms. The participation of each main pathogenic mechanism in a given experimental model is analyzed and proves to vary with each particular model and site studied. The importance of various experimental models in the evaluation of different therapeutic procedures directed to control the genesis and evolution of brain edema is stressed.