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Results 251 - 300 of 1469
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Ebert Douglas - - 2003
Glucose is the dominant oxidative fuel for brain, but studies have indicated that fatty acids are used by brain as well. We postulated that fatty acid oxidation in brain could contribute significantly to overall energy usage and account for non-glucose-derived energy production. [2,4,6,8-13C4]octanoate oxidation in intact rats was determined by ...
Di Marzo Vincenzo - - 2003
An article appearing in this issue of the British Journal of Pharmacology shows for the first time that the general anaesthetic propofol inhibits one of the enzymes catalysing endocannabinoid hydrolysis and inactivation, the fatty acid amide hydrolase, thereby enhancing the brain levels of anandamide and 2-arachidonoylglycerol in mouse brain. The ...
Li Yu-Teh - - 2003
Tay-Sachs disease (TSD) is a classical glycosphingolipid (GSL) storage disease. Although the genetic and biochemical bases for a massive cerebral accumulation of ganglioside GM2 in TSD have been well established, the mechanism for the neural dysfunction in TSD remains elusive. Upon analysis of GSLs from a variant B TS brain, ...
Youssef Jihan A - - 2003
While studies showed that aging is accompanied by increased exposure of the brain to oxidative stress, others have not detected any age-correlated differences in levels of markers of oxidative stress. Use of conventional markers of oxidative damage in vivo, which may be formed ex vivo and/or eliminated by endogenous metabolism, ...
Kölker S - - 2003
The neurometabolic disorder glutaryl-CoA dehydrogenase (GCDH) deficiency is biochemically characterised by an accumulation of the marker metabolites 3-hydroxyglutaric acid, glutaric acid, and glutarylcarnitine. If untreated, the disease is complicated by acute encephalopathic crises, resulting in neurodegeneration of vulnerable brain regions, in particular the putamen. 3-hydroxyglutaric acid is considered the major ...
Brown Finbar O - - 2003
Various Nafion coating procedures were examined in order to design a simple and reproducible coating method to maximise permselective characteristics, and thus eliminate signals from electroactive interferents, in sensors designed for direct in vivo measurements in the brain. Interferents investigated included ascorbic acid (AA), the principal endogenous electroactive interferent present ...
Dieterich Daniela C - - 2003
L-asparaginases catalyse the formation of the neuroactive amino acid L-aspartate by deamination of asparagine. The major pathophysiological significance of L-asparaginase activity is in its clinical use for the treatment of acute lymphatic leukaemia and neoplasias that require asparagine and obtain it from circulating pools. Here we report the identification and ...
Beuthien-Baumann B - - 2003
3-O-Methyl-6-[(18)F]fluoro-L-DOPA (OMFD) is a major metabolite of 6-[(18)F]fluoro-L-DOPA. Although synthesis of OFMD was primarily established to study the dopaminergic system, as it is an amino acid analogue, uptake in experimental tumours has been found. The aim of this study was to evaluate the applicability of OMFD for brain tumour imaging ...
Furuya Shigeki - - 2003
L-Serine is a non-essential amino acid that can be synthesized in the body. It derives from an intermediate of the glycolytic pathway, 3-phosphoglycerate, and utilized for the syntheses of proteins, other amino acids, membrane lipids, heme, and nucleotides. Emerging evidence indicates that L-serine functions as a glia-derived trophic factor, which ...
Yamasaki Izumi - - 2003
While brain development during embryogenesis has been extensively studied in precocial birds, there is no information available on altricial birds. Thus, the concentrations of the catecholamines norepinephrine (NE), epinephrine (E), and dopamine (DA), and the dopaminergic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and 4-hydroxy-3-methoxyphenylacetic acid (HVA) were determined at several stages during ...
Ferrari Luis A - - 2003
Fifteen cases of fatal massive methanol intoxication have been investigated. Victims received either no treatment or ethanol therapeutic treatment. Methanol poisoning cases were classified in three groups according to survival time: more than 3 days (group 1), up to 3 days (group 2) and few hours (group 3). Body distribution ...
Oprica M - - 2003
The evidence of inflammatory processes in the clinical manifestations and neuropathological sequelae of epilepsy have accumulated in the last decade. Administration of kainic acid, an analogue of the excitatory amino acid glutamate, induces a characteristic behavioural syndrome and a reproducible pattern of neurodegeneration in several brain areas, closely resembling human ...
Balata Sherzad - - 2003
Hyperammonemia is a universal finding after gastrointestinal hemorrhage in cirrhosis. We administered an oral amino acid solution mimicking the hemoglobin molecule to examine neuropsychological changes, brain glutamine levels, and brain magnetization transfer ratio (MTR). Forty-eight metabolically stable patients with cirrhosis and no evidence of "overt" hepatic encephalopathy (HE) were randomized ...
de Oliveira Marques Fernanda - - 2003
This study investigated the effects of glutaric acid, which predominantly accumulates in glutaric acidemia type I, on some in vitro parameters of oxidative stress in brain of young rats. We evaluated chemiluminescence, total radical-antioxidant potential (TRAP) and the activities of the antioxidant enzymes catalase, glutathione peroxidase and superoxide dismutase in ...
Chu Constance J - - 2003
N-Arachidonoyldopamine (NADA) was recently identified as an endogenous ligand for the vanilloid type 1 receptor (VR1). Further analysis of the bovine striatal extract from which NADA was isolated indicated the existence of substances corresponding in molecular mass to N-oleoyldopamine (OLDA), N-palmitoyldopamine (PALDA), and N-stearoyldopamine (STEARDA). Quadrupole time-of-flight mass spectrometric analysis ...
Mozzi Rita - - 2003
Phosphatidylserine (PtdSer) is involved in cell signaling and apoptosis. The mechanisms regulating its synthesis and degradation are still not defined. Thus, its role in these processes cannot be clearly established at molecular level. In higher eukaryotes, PtdSer is synthesized from phosphatidylethanolamine or phosphatidylcholine through the exchange of the nitrogen base ...
Miller Robert R RR - - 2003
In order to study the effects of exogenous EtOH and/or Fe(+2) on membrane lipid peroxidation, exogenous EtOH, FeCl(2), FeCl(2) & EtOH, NaCl and NaCl & EtOH were injected into fertile chicken eggs. Controls were either shams or injected with saline. These injections were made at 0 days or 0-2 days ...
Carson Richard E - - 2003
The 5-HT1A ligands [ 18F]FPWAY and [ 18F]FCWAY are metabolized to [ 18F]fluorobenzoic acid (FB) and [ 18F]fluorocyclohexanecarboxylic acid (FC), respectively. To quantify the penetration of these acids into the brain, dynamic positron emission tomography studies were performed in rhesus monkeys with [ 18F]FB and [ 18F]FC. High-performance liquid chromatography ...
Hiramatsu Midori - - 2003
Guanidino compounds of guanidinoethanesulfonic acid, guanidinoacetic acid, guanidinosuccinic acid, N-acetylarginine, beta-guanidinopropionic acid, creatinine, gamma-guanidinobutyric acid, arginine, guanidine, methylguanidine, homoarginine and alpha-guanidinoglutaric acid are present in the mammalian brain. These guanidino compounds except for arginine and guanidine induce seizures and convulsions in rat, rabbit and cat by intracisternal injection. Hirudonine, audonine, ...
Pellicciari Roberto - - 2003
A novel potent and selective kynurenine-3-hydroxylase inhibitor is descibed along a preliminary evaluation in a in vivo gerbil model of its ability to increase the kynurenine and kynurenic acid concentration in both plasma and brain. These data support the notion that kynurenine-3-hydroxylase inhibitors may have a sustained therapeutic potential in ...
Mazzio Elizabeth - - 2003
1-Methyl-4-phenylpyridinium (MPP+) is a mitochondrial Complex I inhibitor and is frequently used to investigate the pathological degeneration of neurons associated with Parkinson's disease (PD). In vitro, extracellular concentration of glucose is one of the most critical factors in establishing the vulnerability of neurons to MPP+ toxicity. While glucose is the ...
Davidson Bruce C - - 2003
BACKGROUND: Considerable evidence indicates that polyunsaturated fatty acids are important in normal brain structure and function. MATERIALS AND METHODS: Rat brain striatal slices incubated with tritiated dopamine were electrically stimulated twice. During the first only buffer was perfused. During the second period buffer, fatty acid plus indomethacin, or fatty acid ...
Yamamoto Takanobu - - 2003
The level of tryptophan and 5-hydroxyindoleacetic acid were measured in the brain (striatum) of rats on tryptophan-deficient diet and tryptophan-enriched diet. We measured concentrations of tryptophan and 5-hydroxyindoleacetic acid in striatum by using microdialysis and HPLC methods. The extracellular level of tryptophan and 5-hydroxyindoleacetic acid concentration in the striatum of ...
Smythe George A - - 2003
To study the complex inter-relationships between inflammatory and apoptotic responses and the kynurenine pathway, we have utilized electron-capture negative ion mass spectrometry to develop trace analyses to concurrently quantify nicotinic acid (NIC), picolinic acid (PIC) and quinolinic acid (QUIN) in biological samples. We have shown that NIC and its amide ...
Topczewska-Bruns Joanna - - 2003
Tryptophan metablolism via kynureninc pathway leads to the formation of several neuroactive substances including kynurenine, anthranilic acid and quinolinic acid, which are involved in numerous neurodegenerative diseases. Also chronic renal insufficiency is associated with neurological disturbances but it is still not clear which substances are responsible for those disorders. Thus, ...
Pocernich Chava B - - 2003
In Alzheimer's disease (AD) brain increased lipid peroxidation and decreased energy utilization are found. Mitochondria membranes contain a significant amount of arachidonic and linoleic acids, precursors of lipid peroxidation products, 4-hydroxynonenal (HNE) and 2-propen-1-al (acrolein), that are extremely reactive. Both alkenals are increased in AD brain. In this study, we ...
Walker J Michael - - 2002
The brain produces at least five compounds that possess sub-micromolar affinity for cannabinoid receptors: anandamide, 2-arachidonoylglycerol, noladin ether, virodhamine, and N-arachidonoyldopamine (NADA). One function of these and/or related compounds is to suppress pain sensitivity. Much evidence supports a role of endocannabinoids in pain modulation in general, and some evidence points ...
Yoshida Hirotaka - - 2002
Tau is a major microtubule-associated protein in mammalian brain, where it exists as multiple isoforms that are produced from a single gene by alternative mRNA splicing. Here we present the first report on the structure and function of tau protein from a nonmammalian vertebrate. In the adult chicken brain, five ...
Briscoe Celia P - - 2003
GPR40 is a member of a subfamily of homologous G protein-coupled receptors that include GPR41 and GPR43 and that have no current function or ligand ascribed. Ligand fishing experiments in HEK293 cells expressing human GPR40 revealed that a range of saturated and unsaturated carboxylic acids with carbon chain lengths greater ...
Shah Ajit J - - 2002
Amino acids in the central nervous system can be divided into non-neurotransmitter or neurotransmitter depending on their function. The measurement of these small molecules in brain tissue and extracellular fluid has been used to develop effective treatment strategies for neuropsychiatric and neurodegenerative diseases and for the diagnosis of such pathologies. ...
Wang T - - 2002
Rana oocytes have previously been shown to contain much more soluble tubulin than does the brain, suggesting different assembly and disassembly dynamics of frog oocyte tubulin compared to that in brain. By using centrifugation, SDS-PAGE, two-dimensional gel electrophoresis and Western blots, probed with anti-alpha-tubulin monoclonal antibodies, polymorphic alpha-tubulins (isoforms) were ...
Purdon A D - - 2002
Until recently, brain phospholipid metabolism was thought to consume only 2% of the ATP consumed by the mammalian brain as a whole. In this paper, however, we calculate that 1.4% of total brain ATP consumption is consumed for the de novo synthesis of ether phospholipids and that another 5% is ...
Serrano M I - - 2002
Taurine is a nonessential amino acid that is of medical interest for the nutrition of infants. Taurine has been found in the central nervous system of rodents and humans, and among its potential therapeutic uses, it is interesting to remark its analgesic actions. It is also well known that concentration ...
Ohtsuki Sumio - - 2002
Renal impairment is associated with CNS dysfunctions and the accumulation of uremic toxins, such as indoxyl sulfate, in blood. To evaluate the relevance of indoxyl sulfate to CNS dysfunctions, we investigated the brain-to-blood transport of indoxyl sulfate at the blood-brain barrier (BBB) using the Brain Efflux Index method. [(3)H]Indoxyl sulfate ...
Schwarcz Robert - - 2002
Degradation of the essential amino acid tryptophan along the kynurenine pathway (KP) yields several neuroactive intermediates, including the free radical generator 3-hydroxykynurenine, the excitotoxic N-methyl-D-aspartate (NMDA) receptor agonist quinolinic acid, and the NMDA and alpha7 nicotinic acetylcholine receptor antagonist kynurenic acid. The ambient levels of these compounds are determined by ...
Bergström U - - 2002
Picolinic acid (PA) protects against quinolinic acid- and kainic acid-induced neurotoxicity in the brain. To study the uptake of PA to the brain, we administered [3H]PA via a unilateral nasal instillation or iv injection to mice. Autoradiography demonstrated a rapid uptake of radioactivity in the olfactory nerve layer and in ...
Augood Sarah J - - 2002
Indices of dopamine transmission were measured in the postmortem striatum of DYT1 dystonia brains. A significant increase in the striatal 3,4-dihydroxyphenylacetic acid/dopamine ratio was found. Quantitative autoradiography revealed no differences in the density of dopamine transporter or vesicular monoamine transporter-2 binding; however, there was a trend toward a reduction in ...
Zou Wen-Quan - - 2002
In the presence of a low concentration of denaturants or detergents, acidic pH triggers a conformational transition of alpha-helices into beta-sheets in recombinant prion protein (PrP), likely mimicking some aspects of the transformation of host-encoded normal cellular PrP (PrP(C)) into its pathogenic isoform (PrP(Sc)). Here we observed the effects of ...
Latchman David S - - 2002
Urocortin (Ucn) is a 40 amino acid peptide which is closely related to corticotrophin-releasing factor (CRF). It is expressed in specific regions of the brain but is also detectable in other organs notably the heart. Although some of the effects of Ucn in the nervous system such as enhanced anxiety ...
Fam Samuel S - - 2002
Free radical-initiated oxidant injury and lipid peroxidation have been implicated in a number of neural disorders. Docosahexaenoic acid is the most abundant unsaturated fatty acid in the central nervous system. We have shown previously that this 22-carbon fatty acid can yield, upon oxidation, isoprostane-like compounds termed neuroprostanes, with E/D-type prostane ...
Lichtman Aron H - - 2002
Fatty acid amides (FAAs) represent a class of neuromodulatory lipids that includes the endocannabinoid anandamide and the sleep-inducing substance oleamide. Both anandamide and oleamide produce behavioral effects indicative of cannabinoid activity, but only anandamide binds the cannabinoid (CB1) receptor in vitro. Accordingly, oleamide has been proposed to induce its behavioral ...
Bachmann Claude - - 2002
Hyperammonemia is mainly found in hepatic encephalopathy and in genetic defects of the urea cycle or other pathways of the intermediary metabolism. Clinically a difference has to be made between chronic moderate hyperammonemia and acutely increased concentrations. Pathogenetic mechanisms of ammonia toxicity to the brain are partly unraveled. In some ...
Takanaga Hitomi - - 2002
Although system A is present at the blood-brain barrier (BBB), the physiological roles of system A have not been clarified. The efflux transport of the substrates of system A, such as L-proline (L-Pro), glycine (Gly), and alpha-methylaminoisobutyric acid (MeAIB), across the BBB was investigated using the in vivo Brain Efflux ...
Yehuda Shlomo - - 2002
Tyrosine is unable to cross the blood-brain barrier and is therefore unable to improve the status of brain dopamine (DA) and to provide relief for patients with Parkinson's disease (PD) or other DA-insufficient disorders. We report the creation of an amide bond molecule [N-(alpha-linolenoyl)tyrosine (NLT)] that combines tyrosine with a ...
Landén Mikael - - 2002
The 'membrane hypothesis' of schizophrenia postulates a disturbance in the metabolism and structure of membrane phospholipids resulting in a disturbance in the function of neuronal membrane proteins. Most studies exploring this hypothesis have examined components of peripheral blood. Since it may be questioned if these peripheral measurements reflect changes in ...
Battino Maurizio - - 2002
Coenzyme Q distribution, as well as respiratory chain features, in rat brain mitochondria depend on mitochondrial subpopulation, brain region and age. Heavy mitochondria (HM) usually display the lowest content of respiratory components and the lowest enzymatic activities and it has been suggested that they represent the oldest mitochondrial population. In ...
Zielke H Ronald - - 2002
Maple syrup urine disease (MSUD) and phenylketonuria (PKU) are associated with accumulation of large neutral amino acids (LNAA) in blood and tissues and a decrease of other LNAA not directly related to the enzyme defects. One characteristic shared by both the elevated and decreased amino acids is that all are ...
James J Howard - - 2002
BACKGROUND: Early theories or hepatic encephalopathy focused on ammonia-driven disruption of the Krebs cycle and cellular energy production. The "false-neurotransmitter" theory directed attention toward the interactions of amino acids, metabolism, the blood-brain barrier and neurotransmission. As they evolved, these studies revealed surprising and subtle effects of ammonia on brain amino ...
Qi Kemin - - 2002
Brain is highly enriched in long-chain polyunsaturated fatty acids (PUFAs), particularly arachidonic acid and docosahexaenoic acid, which play important roles in brain structural and biologic functions. Plasma transport, in the form of free fatty acids or esterified FAs in lysophosphatidylcholine and lipoproteins, and de-novo synthesis contribute to brain accretion of ...
Toda Shizuo - - 2002
We present the results of an in vitro investigation of the inhibitory effects of phenylpropanoid metabolites on copper-induced protein oxidative modification of mice brain homogenate. The effects of caffeic acid, 3-(3, 4-dihydroxyphenyl)-L-alanine, esculetin, ferulic acid, and scopoletin were stronger than that of mannitol as a free-radical scavenger, whereas the effects ...
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