scholarly journals Angiography Analysis of Variations of the Posterior Segment of the Circle of Willis

2005 ◽  
Vol 5 (3) ◽  
pp. 30-34 ◽  
Author(s):  
Alma Voljevica ◽  
Amela Kulenović ◽  
Eldan Kapur ◽  
Ilvana Vučković
Keyword(s):  
Blood Circulation ◽  
Vascular Diseases ◽  
Circle Of Willis ◽  
Posterior Segment ◽  
Target Groups ◽  
Male Patients ◽  
High Level ◽  
The Brain ◽  
Collateral Blood Circulation ◽  
Cerebral Vascular

Cerebral-vascular diseases present one of the leading problems of the modern mankind. They are followed by the risk of high mortality rate, and as such cause high level of disability with people who survive cerebral-vascular incident (stroke, apoplexy). Researches done so far proved that beginning, course and result of the cerebral-vascular diseases depend immensely of the possibility to establish collateral blood circulation and first of all on so called tertian level that is actually the circle of Willis. The circle of Willis, thanks to communicating segments, provide detour way to procure parts of the brain which, due to insufficiency, do not get enough quantity of blood. In this particular study by the analysis of 150 MRI patient’s angiographies of the circle of Willis that had been processed at the Radiology Institute of the Clinic Center of University in Sarajevo, we tried to present the most common variations of the posterior segment of the circle of Willis with patients who did not have signs of the cerebral-vascular diseases. The analysis included two target groups (above 60 years old and younger than 34 years old) and both genders. By the analysis of the angiographies of the circle of Willis we reached following results: complete posterior configuration of the circle of Willis has been found with all patients in 54% of cases, but in some slightly higher percentage complete posterior configuration is noted with younger category of patients compared to elderly patients, and in some higher percentage with female compared to male patients. Out of variations that damage the posterior segment of the circle of Willis the first one, according to the frequency of occurring, is the variation of the type of unilateral fetal sort of posterior cerebral artery, and then the variation marked as unilateral aplasia or hypoplasia of the posterior communicating artery.

scholarly journals Potential of Glucagon-Like Peptide 1 as a Regulator of Impaired Cholesterol Metabolism in the Brain

2020 ◽  
Vol 11 (6) ◽  
pp. 1686-1695
Author(s):  
Young-Kook Kim ◽  
Juhyun Song
Keyword(s):  
Blood Vessel ◽  
Blood Vessels ◽  
Cholesterol Metabolism ◽  
Vascular Diseases ◽  
Cholesterol Homeostasis ◽  
Cerebral Vessel ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1 ◽  
The Brain ◽  
Cerebral Vascular

ABSTRACT Cerebral vascular diseases are the most common high-mortality diseases worldwide. Their onset and development are associated with glycemic imbalance, genetic background, alteration of atherosclerotic factors, severe inflammation, and abnormal cholesterol metabolism. Recently, the gut–brain axis has been highlighted as the key to the solution for cerebral vessel dysfunction in view of cholesterol metabolism and systemic lipid circulation. In particular, glucagon-like peptide 1 (GLP-1) is a cardinal hormone that regulates blood vessel function and cholesterol homeostasis and acts as a critical messenger between the brain and gut. GLP-1 plays a systemic regulatory role in cholesterol homeostasis and blood vessel function in various organs through blood vessels. Even though GLP-1 has potential in the treatment and prevention of cerebral vascular diseases, the importance of and relation between GLP-1 and cerebral vascular diseases are not fully understood. Herein, we review recent findings on the functions of GLP-1 in cerebral blood vessels in association with cholesterol metabolism.

‘To unlock the secret places of Man’s Mind’.1 Thomas Willis (1621–1675)

2021 ◽  
pp. 096777202110007
Author(s):  
Penelope Hunting
Keyword(s):  
Medical Practice ◽  
Natural Philosophy ◽  
Circle Of Willis ◽  
High Street ◽  
The Brain

Thomas Willis was born four hundred years ago on 27 January 1621 in Wiltshire. He has been dubbed ‘the father of neurology’ and is remembered for the Circle of Willis at the base of the brain. Young Thomas was educated at Oxford as a schoolboy and undergraduate. From 1646 he practised medicine and studied chemistry; he joined the Oxford Experimental Philosophical Club, and was Sedleian Professor of Natural Philosophy from 1660. He established a prosperous medical practice at The Angel on Oxford High Street, and achieved international acclaim for Cerebri anatome (1664). Lured to London in 1667, Willis lived in style but attended the sick poor on Sundays and worshipped twice daily at St Martin-in-the-Fields.

scholarly journals Acute Changes in Blood Pressure Following Vascular Diseases in the Brain Stem

Stroke ◽  
1973 ◽  
Vol 4 (1) ◽  
pp. 80-84 ◽  
Author(s):  
AKIRA ITO ◽  
TERUO OMAE ◽  
SHIBANOSUKE KATSUKI
Keyword(s):  
Blood Pressure ◽  
Brain Stem ◽  
Vascular Diseases ◽  
Acute Changes ◽  
The Brain

scholarly journals Astroglial Integrins in the Development and Regulation of Neurovascular Units

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Hironobu Tanigami ◽  
Takayuki Okamoto ◽  
Yuichi Yasue ◽  
Motomu Shimaoka
Keyword(s):  
Central Nervous System ◽  
Cell Adhesion Molecules ◽  
Energy Demand ◽  
Vascular Tone ◽  
Neurovascular Unit ◽  
Neuronal Synapses ◽  
The Central Nervous System ◽  
The Brain ◽  
Signaling Activity ◽  
Cerebral Vascular

In the neurovascular units of the central nervous system, astrocytes form extensive networks that physically and functionally connect the neuronal synapses and the cerebral vascular vessels. This astrocytic network is thought to be critically important for coupling neuronal signaling activity and energy demand with cerebral vascular tone and blood flow. To establish and maintain this elaborate network, astrocytes must precisely calibrate their perisynaptic and perivascular processes in order to sense and regulate neuronal and vascular activities, respectively. Integrins, a prominent family of cell-adhesion molecules that support astrocytic migration in the brain during developmental and normal adult stages, have been implicated in regulating the integrity of the blood brain barrier and the tripartite synapse to facilitate the formation of a functionally integrated neurovascular unit. This paper describes the significant roles that integrins and connexins play not only in regulating astrocyte migration during the developmental and adult stages of the neurovascular unit, but also in general health and in such diseases as hepatic encephalopathy.

scholarly journals A neurocognitive model of ideological thinking

2021 ◽  
pp. 1-15
Author(s):  
Leor Zmigrod
Keyword(s):  
Empirical Evidence ◽  
Motivational Factors ◽  
Cognitive Systems ◽  
Social Forces ◽  
Low Level ◽  
Cognitive Principles ◽  
High Level ◽  
Ideological Attitudes ◽  
The Brain

Abstract Ideological behavior has traditionally been viewed as a product of social forces. Nonetheless, an emerging science suggests that ideological worldviews can also be understood in terms of neural and cognitive principles. The article proposes a neurocognitive model of ideological thinking, arguing that ideological worldviews may be manifestations of individuals’ perceptual and cognitive systems. This model makes two claims. First, there are neurocognitive antecedents to ideological thinking: the brain’s low-level neurocognitive dispositions influence its receptivity to ideological doctrines. Second, there are neurocognitive consequences to ideological engagement: strong exposure and adherence to ideological doctrines can shape perceptual and cognitive systems. This article details the neurocognitive model of ideological thinking and synthesizes the empirical evidence in support of its claims. The model postulates that there are bidirectional processes between the brain and the ideological environment, and so it can address the roles of situational and motivational factors in ideologically motivated action. This endeavor highlights that an interdisciplinary neurocognitive approach to ideologies can facilitate biologically informed accounts of the ideological brain and thus reveal who is most susceptible to extreme and authoritarian ideologies. By investigating the relationships between low-level perceptual processes and high-level ideological attitudes, we can develop a better grasp of our collective history as well as the mechanisms that may structure our political futures.

scholarly journals Perceptual decisions are biased toward relevant prior choices

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Helen Feigin ◽  
Shira Baror ◽  
Moshe Bar ◽  
Adam Zaidel
Keyword(s):  
Sensory Information ◽  
Irrelevant Stimulus ◽  
Stimulus Feature ◽  
Serial Dependence ◽  
Low Level ◽  
Subsequent Test ◽  
Key Factor ◽  
High Level ◽  
Motor Actions ◽  
The Brain

AbstractPerceptual decisions are biased by recent perceptual history—a phenomenon termed 'serial dependence.' Here, we investigated what aspects of perceptual decisions lead to serial dependence, and disambiguated the influences of low-level sensory information, prior choices and motor actions. Participants discriminated whether a brief visual stimulus lay to left/right of the screen center. Following a series of biased ‘prior’ location discriminations, subsequent ‘test’ location discriminations were biased toward the prior choices, even when these were reported via different motor actions (using different keys), and when the prior and test stimuli differed in color. By contrast, prior discriminations about an irrelevant stimulus feature (color) did not substantially influence subsequent location discriminations, even though these were reported via the same motor actions. Additionally, when color (not location) was discriminated, a bias in prior stimulus locations no longer influenced subsequent location discriminations. Although low-level stimuli and motor actions did not trigger serial-dependence on their own, similarity of these features across discriminations boosted the effect. These findings suggest that relevance across perceptual decisions is a key factor for serial dependence. Accordingly, serial dependence likely reflects a high-level mechanism by which the brain predicts and interprets new incoming sensory information in accordance with relevant prior choices.

scholarly journals Ion Channels as New Attractive Targets to Improve Re-Myelination Processes in the Brain

2021 ◽  
Vol 22 (14) ◽  
pp. 7277
Author(s):  
Federica Cherchi ◽  
Irene Bulli ◽  
Martina Venturini ◽  
Anna Maria Pugliese ◽  
Elisabetta Coppi
Keyword(s):  
Ion Channels ◽  
Demyelinating Disease ◽  
Oligodendrocyte Progenitor Cells ◽  
Target Groups ◽  
Synaptic Inputs ◽  
Drug Actions ◽  
The Central Nervous System ◽  
Therapeutic Mechanisms ◽  
Voltage Gated Channels ◽  
The Brain

Multiple sclerosis (MS) is the most demyelinating disease of the central nervous system (CNS) characterized by neuroinflammation. Oligodendrocyte progenitor cells (OPCs) are cycling cells in the developing and adult CNS that, under demyelinating conditions, migrate to the site of lesions and differentiate into mature oligodendrocytes to remyelinate damaged axons. However, this process fails during disease chronicization due to impaired OPC differentiation. Moreover, OPCs are crucial players in neuro-glial communication as they receive synaptic inputs from neurons and express ion channels and neurotransmitter/neuromodulator receptors that control their maturation. Ion channels are recognized as attractive therapeutic targets, and indeed ligand-gated and voltage-gated channels can both be found among the top five pharmaceutical target groups of FDA-approved agents. Their modulation ameliorates some of the symptoms of MS and improves the outcome of related animal models. However, the exact mechanism of action of ion-channel targeting compounds is often still unclear due to the wide expression of these channels on neurons, glia, and infiltrating immune cells. The present review summarizes recent findings in the field to get further insights into physio-pathophysiological processes and possible therapeutic mechanisms of drug actions.

scholarly journals The Potential Roles of Blood–Brain Barrier and Blood–Cerebrospinal Fluid Barrier in Maintaining Brain Manganese Homeostasis

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1833
Author(s):  
Shannon Morgan McCabe ◽  
Ningning Zhao
Keyword(s):  
Cerebrospinal Fluid ◽  
Blood Brain Barrier ◽  
Blood Circulation ◽  
Critical Role ◽  
Systemic Circulation ◽  
Brain Parenchyma ◽  
Brain Barrier ◽  
Blood Brain ◽  
The Brain

Manganese (Mn) is a trace nutrient necessary for life but becomes neurotoxic at high concentrations in the brain. The brain is a “privileged” organ that is separated from systemic blood circulation mainly by two barriers. Endothelial cells within the brain form tight junctions and act as the blood–brain barrier (BBB), which physically separates circulating blood from the brain parenchyma. Between the blood and the cerebrospinal fluid (CSF) is the choroid plexus (CP), which is a tissue that acts as the blood–CSF barrier (BCB). Pharmaceuticals, proteins, and metals in the systemic circulation are unable to reach the brain and spinal cord unless transported through either of the two brain barriers. The BBB and the BCB consist of tightly connected cells that fulfill the critical role of neuroprotection and control the exchange of materials between the brain environment and blood circulation. Many recent publications provide insights into Mn transport in vivo or in cell models. In this review, we will focus on the current research regarding Mn metabolism in the brain and discuss the potential roles of the BBB and BCB in maintaining brain Mn homeostasis.

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