Structural changes of the human superior cervical ganglion following ischemic stroke

OBJECTIVE: The sympathetic nervous system participates in the modulation of cerebrovascular autoregulation. The most important source of sympathetic innervation of the cerebral arteries is the superior cervical ganglion. The aim of this study was to investigate signs of the neurodegenerative alteration in the sympathetic ganglia including the evaluation of apoptosis of neuronal and satellite cells in the human superior cervical ganglion after ischemic stroke, because so far alterations in human sympathetic ganglia related to the injury to peripheral tissue have not been enough analyzed. MATERIALS AND METHODS: We investigated human superior cervical ganglia from eight patients who died of ischemic stroke and from seven control subjects. Neurohistological examination of sympathetic ganglia was performed on 5 microm paraffin sections stained with cresyl violet. TUNEL method was applied to assess apoptotic cells of sympathetic ganglia. RESULTS: The present investigation showed that: (1) signs of neurodegenerative alteration (darkly stained and deformed neurons with vacuoles, lymphocytic infiltrates, gliocyte proliferation) were markedly expressed in the ganglia of stroke patients; (2) apoptotic neuronal and glial cell death was observed in the human superior cervical ganglia of the control and stroke groups; (3) heterogenic distribution of apoptotic neurons and glial cells as well as individual variations in both groups were identified; (4) higher apoptotic index of sympathetic neurons (89%) in the stroke group than in the control group was found. CONCLUSIONS: We associated these findings with retrograde reaction of the neuronal cell body to axonal damage, which occurs in the ischemic focus of blood vessels innervated by superior cervical ganglion.publishersversionPeer reviewe

Morphology of human intracardiac nerves: an electron microscope study

Since many human heart diseases involve both the intrinsic cardiac neurons and nerves, their detailed normal ultrastructure was examined in material from autopsy cases without cardiac complications obtained no more than 8 h after death. Many intracardiac nerves were covered by epineurium, the thickness of which was related to nerve diameter. The perineurial sheath varied from nerve to nerve and, depending on nerve diameter, contained up to 12 layers of perineurial cells. The sheaths of the intracardiac nerves therefore become progressively attenuated during their course in the heart. The intraneural capillaries of the human heart differ from those in animals in possessing an increased number of endothelial cells. A proportion of the intraneural capillaries were fenestrated. The number of unmyelinated axons within unmyelinated nerve fibres was related to nerve diameter, thin cardiac nerves possessing fewer axons. The most distinctive feature was the presence of stacks of laminated Schwann cell processes unassociated with axons that were more frequent in older subjects. Most unmyelinated and myelinated nerve fibres showed normal ultrastructure, although a number of profiles displayed a variety of different axoplasmic contents. Collectively, the data provide baseline information on the normal structure of intracardiac nerves in healthy humans which may be useful for assessing the degree of nerve damage both in autonomic and sensory neuropathies in the human heart

Hilum of the heart

Qui a fermé les portes de la mer ?Livre de Job Rivières, canaux, sources ou puits, nous connaissons mieux maintenant l’eau en travail sur la terre que Dieu a donnée aux hommes. Élément essentiel de la composition de l’univers, elle est, d’abord, mouvement toujours recommencé : pluie, ruissellement, disparition, résurgence, évaporation et pluie encore. Même si ce grand cycle se suspend par instants pour retenir l’eau au tréfonds du sol, avant de la relâcher de nouveau à l’air libre, c’est bien..

Thickness of cerebral cortex measured using anatomical mesoscopic imaging and magnetic resonance imaging

Objective. Magnetic resonance imaging method opened up the possibility for in vivo examination of the anatomy of human brain. For this reason it is interesting and relevant to compare the knowledge accumulated over a number of years during the examination of the composition of dead brain to that obtained from magnetic resonance images. The aim of this study was to determine and compare the thickness of cerebral cortex in human of different age and sex, measured in different sites of the hemispheres when applying anatomical mesoscopic imaging and magnetic resonance imaging. Material and methods. The thickness of cerebral cortex was measured in symmetrical Brodmann’s areas of both hemispheres. The anatomical mesoscopic imaging technique was used for the examination of 2×2-cm cortex samples obtained during autopsy and fixed for 4 weeks in 10% paraformaldehyde. In these samples, cortex thickness was measured in sections perpendicular to the convolution, using an operative microscope, in a mesoscopic image at ×16 magnification and with an accuracy of 0.01 mm. Using cerebral magnetic resonance imaging, the thickness of cerebral cortex in live subjects was measured on T1-weighted images of patients examined at the Clinic of Radiology, Kaunas University of Medicine Hospital. The measured cortical field image was magnified to the smallest element of digital image – the pixel – and measured with an accuracy of 0.01 mm. Each of the two techniques was applied for the examination of 20 men and women who were divided into age groups of 20–60 years (n=10) and older than 60 years (n=10). Results and conclusions. Both examination methods yielded a statistically significant difference in the thickness of cerebral cortex between Brodmann’s areas 1, 4, and 19. No significant difference in cortex thickness was found between different age and sex groups; however, the findings showed that the difference in cortex thickness between the different age male groups was 4.6% and female – 1.6%. No significant difference using different techniques was found, but the cortex thickness in the fixed samples was reduced by 0.5 cm on average