Incidence and morphometry of caroticoclinoid foramina in Greek dry human skulls.

BACKGROUND: Ossification of the caroticoclinoid ligament (CCL) and formation of a caroticoclinoid foramen (CCF) may impose significant risk to neurosurgeons by impeding mobilization of the cavernous segment of the internal carotid artery. Although safe surgical access to the clinoidal space is related to understanding the CCF anatomical and ethnic variants, there remains a paucity of studies of the morphology and bony relationships. The current study provides a systematic morphological and morphometric analysis of the CCF, the ossification of the CCL extending between the anterior and middle clinoid processes, and their relations in a Greek population. MATERIALS AND METHODS: The incidence of unilateral and bilateral CCF, types (complete, incomplete, and contact) of ossified CCLs, and foramina diameter according to side and gender were determined in 76 Greek adult dry skulls. Findings were correlated with the morphology of optic strut (OS) (presulcal, sulcal, postsulcal, and asymmetric). RESULTS: A CCF was detected in 74% of the specimens. The majority of skulls (51.4%) had bilateral CCF, whereas 22.3% of the skulls had unilateral foramina. Incomplete CCF were observed in 69.3%, complete in 19.8%, and contact type in 10.9%. The mean CCF diameter was 0.55 ± 0.07 cm on the left and 0.54 ± 0.08 cm on the right side. Side symmetry existed, although there were no significant differences according to gender. The CCF were more prominent in skulls with a sulcal type of OS. CONCLUSIONS: The results of the present study augment the current knowledge on the morphology of key anatomical landmarks, CCF, and CCL ossification in the sellar area, indicating population differences. A significant side asymmetry in caroticoclinoid osseous bridging and foramina is highlighted. These findings are necessary for a safe surgical access to the clinoidal area.

Distribution of SRPK1 in human brain.

Extensive alternative splicing is observed in the mammalian nervous system providing for protein diversity and specificity to accomplish the complex neuronal functions. Mechanisms underlying neuron specific splicing are not yet well understood. Among the factors regulating splicing of major importance are serine/arginine protein kinases (SRPKs) that phosphorylate SR splicing factors. SRPK1 is known to be expressed in the mammalian central nervous system. The present immunohistochemical study reveals a region- and neuron-specific localization of SRPK1 in human brain. The potential involvement of the kinase in the regulation of alternative splicing of various neuronal proteins is discussed.

The combination of silver techniques for studying the pathology of Alzheimer's disease.

Alzheimer's diseaseis a progressive neurodegenerative disorder, which implicates the whole central nervous system. The hallmarks of the disease are the development of neuritic plaques and neurofibrillary tangles, the accumulation of beta-amyloid in the cytoplasm of the neurons (soluble beta-amyloid oligomers) and the neuropile space (insoluble amyloidal fibrils), the neuronal loss, and the devastating synaptic alterations. Despite the fact that for the identification of the plaques and tangles and for the detection of the amyloid deposits and the neuronal loss, there are specific techniques even in light microscopy, synaptic pathology can be studied only with electron microscopy or indirectly with immunohistochemistry, because several alterations in the density of proteins located in synaptic junction (drebrin, synapsin, synaptophisin) may be occurring. Thus, this article presents original Nauta method impregnating degenerating axons as well as axonic terminals in post-mortem material derived from patients suffering from Alzheimer's disease. Furthermore, the article proposes its application in combination with Golgi method and Gallyas technique for a spheroid view of the neuronal degeneration and synaptic pathology in the study of any brain region in Alzheimer's disease.

Reelin immunoreactivity and morphological analysis of the human visual cortex.

Reelin is a secreted glycoprotein with a crucial role in development of the Central Nervous System. In adults, its function remains unclear but it may be involved in the modulation of synaptic plasticity. Having in mind this possible property of reelin, the authors decided to study the distribution of reelin immunoreactivity in the neurons of the human adult primary visual cortex and compare the findings with morphological analysis (Golgi method) of neuronal networks. The distribution of reelin in the primary visual cortex is different from other cortical area examined; reelin is mostly present in the neurons of second and sixth layer.