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Brain circulation

The internal Tunisian requirements often do not match with the impulse to send engineers abroad with an eye to reintegrate them (sometimes referred to as brain circulation Saxenian 2005). For students and workers who studied and worked abroad before returning to teach in Tunisia, numerous difficulties are described. Because of the necessary personal contacts to get recommendations, even initial steps are difficult and good research positions are hard to come by. Although the top students are seen as leaving for France, they are also seen as having many... [Pg.397]

The prostaglandins in the nervous system have been implicated to have physiological roles in temperature regulation, brain circulation and possibly in neuromodulation [201], The administration of prostaglandins of the E-series intraventricularly has been shown to have sedative effects in rodents and chickens [216]. In the mouse, a dose-dependent inhibition of picotoxin and pentahazol induced convulsion was observed [217,218]. In the cat prostaglandins inhibited penicillin induced seizures [219]. The mechanism of the anticonvulsive action of PGE compounds is not clear. [Pg.18]

Eicosanoids have been suggested to play a part in the pathophysiology of several diseases of brain circulation, such as intravascular aggregation in transient ischaemic attacks (TIA) and in the severe vasospasm occurring after subarachnoid haemorrhage (for review see ref. 228). [Pg.18]

One of the authors (Sean Doran) of this chapter would like to acknowledge and thank TUBITAK for the 2236 Co-Funded Brain Circulation Scheme (co-circulation scheme) partially supported by the ECFP7 Marie Curie Actions-People-COFUND and coordinated by BIIDEB as a source of funding. [Pg.108]

Poly(lactic acid) Nanoparticles Increase Hydrophilicity Facilitate brain circulation... [Pg.112]

Logically, ADH receptor antagonists, and ADH synthesis and release inhibitors can be effective aquaretics. ADH, 8-arginine vasopressin [113-79-17, is synthesized in the hypothalamus of the brain, and is transported through the supraopticohypophyseal tract to the posterior pituitary where it is stored. Upon sensing an increase of plasma osmolaUty by brain osmoreceptors or a decrease of blood volume or blood pressure detected by the baroreceptors and volume receptors, ADH is released into the blood circulation it activates vasopressin receptors in blood vessels to raise blood pressure, and vasopressin V2 receptors of the nephrons of the kidney to retain water and electrolytes to expand the blood volume. [Pg.211]

The chromaffin cells of the adrenal medulla may be considered to be modified sympathetic neurons that are able to synthesize E from NE by /V-methylation. In this case the amine is Hberated into the circulation, where it exerts effects similar to those of NE in addition, E exhibits effects different from those of NE, such as relaxation of lung muscle (hence its use in asthma). Small amounts of E are also found in the central nervous system, particularly in the brain stem where it may be involved in blood pressure regulation. DA, the precursor of NE, has biological activity in peripheral tissues such as the kidney, and serves as a neurotransmitter in several important pathways in the brain (1,2). [Pg.354]

Antidepressants are small heterocyclic molecules entering the circulation after oral administration and passing the blood-brain barrier to bind at numerous specific sites in the brain. They are used for treatment of depression, panic disorders, generalized anxiety disorder, social phobia, obsessive compulsive disorder, and other psychiatric disorders and nonpsychiatric states. [Pg.112]

The blood-brain barrier (BBB) forms a physiological barrier between the central nervous system and the blood circulation. It consists of glial cells and a special species of endothelial cells, which form tight junctions between each other thereby inhibiting paracellular transport. In addition, the endothelial cells of the BBB express a variety of ABC-transporters to protect the brain tissue against toxic metabolites and xenobiotics. The BBB is permeable to water, glucose, sodium chloride and non-ionised lipid-soluble molecules but large molecules such as peptides as well as many polar substances do not readily permeate the battier. [Pg.272]

Primarily hydrolyses esters with longer aliphatic (compared to AChE) or aromatic acyl moiety, such as butyrylcholine (BCh) and benzoylcholine (BzCh). BChE is the primary circulating ChE. It is threefold more abundant than AChE in human blood and is found in liver, lungs, muscles, brain and heart. [Pg.357]

Glycosydation AChE and BChE carry 3 and 9, respectively, N-glycosylation consensus sequences attaching carbohydrate residues to the core protein via asparagines. Different molecular forms of the enzymes in various tissues, show different number and composition of carbohydrate residues. N-glycosylation at all sites was shown to be important for effective biosynthesis, secretion and clearance of ChEs from the circulation. Altered patterns of AChE glycosylation have been observed in the brain and cerebrospinal fluid of Alzheimer s disease (AD) patients, with potential diagnostic value. [Pg.359]

The cytokine leptin is secreted by adipocytes (fat cells) in proportion to the size of the adipose dq>ot and circulates via the bloodstream to the brain, where it ultimately affects feeding behavior, endocrine systems including reproductive function and, at least in rodents, energy expenditure. The major effect of Lqrtin is on the hy-pothalamous, where it suppresses appetite and hence food intake. Leptin exerts its effects via binding to the leptin receptor in the brain (specifically in the hypothalamus), which activates the JAK-STAT Pathway. [Pg.685]

DAT is predominantly expressed by dopaminergic brain neurons, NET by noradrenergic neurons in the central and peripheral nervous system, and SERT is restricted to the axons of serotonergic neurons, which originate in the raphe nuclei and innervate numerous higher brain regions therefore SERT is widely distributed in the brain. Outside the brain, 5HT transport can be measured on non-neuronal cells (e.g. platelets, lympho-blastoid cells and smooth muscle cells) most of the 5HT appearing in the circulation is taken up by platelets. [Pg.839]

Ethanol distributes rapidly, with concentrations in body water 10 times higher than in body fat. The tissues with the greatest blood supply equdibrate most rapidly with arterial blood circulation. Shortly after alcohol ingestion, the ethanol concentration in the brain is higher than the venous concentration. [Pg.5]

The ammonia produced by enteric bacteria and absorbed into portal venous blood and the ammonia produced by tissues are rapidly removed from circulation by the liver and converted to urea. Only traces (10—20 Ig/dL) thus normally are present in peripheral blood. This is essential, since ammonia is toxic to the central nervous system. Should portal blood bypass the liver, systemic blood ammonia levels may rise to toxic levels. This occurs in severely impaired hepatic function or the development of collateral links between the portal and systemic veins in cirrhosis. Symptoms of ammonia intoxication include tremor, slurred speech, blurred vision, coma, and ultimately death. Ammonia may be toxic to the brain in part because it reacts with a-ketoglutarate to form glutamate. The resulting depleted levels of a-ketoglutarate then impair function of the tricarboxylic acid (TCA) cycle in neurons. [Pg.244]


See other pages where Brain circulation is mentioned: [Pg.57]    [Pg.22]    [Pg.490]    [Pg.128]    [Pg.108]    [Pg.353]    [Pg.238]    [Pg.118]    [Pg.585]    [Pg.308]    [Pg.193]    [Pg.57]    [Pg.22]    [Pg.490]    [Pg.128]    [Pg.108]    [Pg.353]    [Pg.238]    [Pg.118]    [Pg.585]    [Pg.308]    [Pg.193]    [Pg.172]    [Pg.93]    [Pg.411]    [Pg.185]    [Pg.265]    [Pg.291]    [Pg.758]    [Pg.10]    [Pg.39]    [Pg.68]    [Pg.116]    [Pg.158]    [Pg.475]    [Pg.501]    [Pg.501]    [Pg.1067]    [Pg.1068]    [Pg.1273]    [Pg.1274]    [Pg.306]    [Pg.359]    [Pg.125]    [Pg.267]    [Pg.12]    [Pg.106]   
See also in sourсe #XX -- [ Pg.342 ]




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