Tyler Hesselberg (traintrip16)
Animals are able to move and react in numerous ways to external stimuli. Thus, environmental stimuli need to be detected, information must be processed and finally an output decision must be transmitted to the musculature to get the animal moving. All these processes depend on the nervous system which comprises an intricate neuronal network and many glial cells. In the last decades, a neurono-centric view on nervous system function channeled most of the scientific interest toward the analysis of neurons and neuronal functions. Neurons appeared early in animal evolution and the main principles of neuronal function from synaptic transmission to propagation of action potentials are conserved during evolution. In contrast, not much is known on the evolution of glial cells that were initially considered merely as static support cells. Although it is now accepted that glial cells have an equally important contribution as their neuronal counterpart to nervous system function, their evolutionary origin is unknown. Did glial cells appear several times during evolution? What were the first roles glial cells had to fulfil in the nervous system? What triggered the formation of the amazing diversity of glial morphologies and functions? Is there a possible mechanism that might explain the appearance of complex structures such as myelin in vertebrates? Here, we postulate a common evolutionary origin of glia and depict a number of selective forces that might have paved the way from a simple supporting cell to a wrapping and myelin forming glial cell. click here © 2020 The Authors. Developmental Neurobiology published by Wiley Periodicals LLC.OBJECTIVE Hematoma enlargement (HE) is associated with clinical outcomes after supratentorial intracerebral hemorrhage (ICH). This study evaluates whether HE characteristics and association with functional outcome differ in deep versus lobar ICH. METHODS Pooled analysis of individual patient data between January 2006 and December 2015 from a German-wide cohort study (RETRACE, I + II) investigating ICH related to oral anticoagulants (OAC) at 22 participating centers, and from one single-center registry (UKER-ICH) investigating non-OAC-ICH patients. Altogether, 1954 supratentorial ICH patients were eligible for outcome analyses, which were separately conducted or controlled for OAC, that is, vitamin-K-antagonists (VKA, n = 1186) and non-vitamin-K-antagonist-oral-anticoagulants (NOAC, n = 107). Confounding was addressed using propensity score matching, cox regression modeling and multivariate modeling. Main outcomes were occurrence, extent, and timing of HE (>33%/>6 mL) and its association with 3-month functionaand only significant after small-medium (1st volume-quarter, deep 3.09 [1.52-6.29], P less then 0.01; lobar 3.86 [1.35-11.04], P = 0.01) as opposed to large-sized ICH (4th volume-quarter, deep 1.09 [0.13-9.20], P = 0.94; lobar 2.24 [0.72-7.04], P = 0.17). INTERPRETATION HE occurrence does not differ among deep and lobar ICH. However, compared to lobar ICH, HE after deep ICH is of greater extent in OAC-ICH, occurs earlier and may be of greater clinical relevance. Overall, clinical significance is more apparent after small-medium compared to large-sized bleedings. © 2020 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.Brain specimens from 30 ostriches were injected with red-dyed latex via the internal carotid arteries (Aa.). The ventral tectal mesencephalic artery (a.), invariably a medium-sized single vessel, was, on the right side, a collateral branch of the caudal branch of the carotid artery (53.4%), a direct branch of the carotid artery (43.3%) and a direct branch of the basilar artery (3.3%) and on the left side, a collateral branch of the caudal branch of the carotid artery (66.7%), a direct branch of the carotid arte