Quantitative analysis of myelinated axons of commissural fibers in the cat brain

There are limited data related to the number of commissural axons found in various species. Although the corpus callosum has been investigated in cat, there are no data on the number of its myelinated axons. Additionally, the number of myelinated axons of anterior, posterior and habenular commissures are not documented for the cat. Therefore, we aimed to examine the topographic distribution and regional numerical differences of myelinated axons in encephalic commissures of the cat. This study was carried out at the Faculty of Medicine, Hacettepe University, Ankara, Turkey, from March 2003 to July 2003. The myelinated axons of the encephalic commissures of one cat were counted in this study. In parts of the corpus callosum, a statistically significant difference was found between rostrum and genu, rostrum and truncus, genu and truncus, genu and splenium and truncus and splenium. However, no statistically significant difference was found between rostrum and splenium. When comparing the number of myelinated axons of anterior, posterior and habenular commissures, statistically significant differences were found between anterior and habenular commissures, and between posterior and habenular commissures. No statistically significant difference was found between anterior and posterior commissures. These numerical data, evaluated by quantitative analytical statistical methods, might be useful in filling the lack of information on the mean numbers of myelinated axons of different commissures. Knowledge of the number of myelinated axons in different parts of the corpus callosum may also be very important when performing surgical procedures of the corpus callosum, such as commissurectomies

Light and electron microscopic examination of human subungual tissue Glomus and lamellated bodies

There is only limited data related to the subungual glomus body. We therefore studied the structure of this organ, aiming to obtain further evidence. Additionally, we encountered undefined receptor like structures in close association with these glomus cells, named them as lamellated bodies and examined both of the structures at light and electron microscopic levels. This study was carried out at the Faculty of Medicine, Hacettepe University, Ankara, Turkey, during the time period May 2001 to March 2002. In this study, the subungual tissues of 4 patients were examined. Within subungual tissue, 2 groups of morphologically significant structures were determined by light microscopy. The first structure was described as glomus body. It was characterized as an encapsulated structure, rich in rounded clear cells filling its central compartment. The latter structure having a lamellated appearance was described as lamellated body. In the electron microscopic examination, lamellated bodies were characterized by central filament rich large cells and surrounding cytoplasmic processes of ensheathing cells, some of which were vacuolated. Glomus bodies were surrounded by a capsule and centrally located numerous rounded cells which reflected the structural features of an active cell. The lamellated bodies are very unusual structures and they are not found in any other part of the body. The structural organization of the ensheathing cells in the lamellated bodies greatly resembles many skin associate receptors. Therefore, we planned future studies by using immunohistochemistry, to reveal nervous elements for structural contribution