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Results 451 - 500 of 1469
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Hodgkins P S - - 1998
Excitotoxic neuronal loss can be precipitated by defects in cerebral energy metabolism. Antagonists of excitatory amino acid receptors, such as the endogenous metabolite kynurenic acid, can effectively block excitotoxic lesions. Using brain tissue slices, the present study was designed to examine a potential link between metabolic status and cerebral kynurenic ...
Rabin O - - 1998
Awake gerbils were subjected to 5 min of forebrain ischemia by clamping the carotid arteries for 5 min and then allowing recirculation. Radiolabeled arachidonic or palmitic acid was infused intravenously for 5 min at the start of recirculation, after which the brains were prepared for quantitative autoradiography or chemical analysis. ...
Huitinga I - - 1998
Annexin-1, a calcium-dependent phospholipid binding protein, has been shown to act as an endogenous central neuroprotectant, notably against cerebral ischaemic damage. In the present study we extend these findings to an animal model of multiple sclerosis, EAE, and report that endogenous annexin-1 is expressed in ED1+ macrophages and resident astrocytes ...
Cherian G - - 1997
Polyunsaturated fatty acid composition and tocopherol status of newly hatched chicks from hens fed diets containing 3.5% menhaden (MO), flax (LO), palm (PO), or sunflower oils (SO) with (+T) or without tocopherols were examined. Addition of tocopherols increased (P < 0.05) the tocopherol content of eggs and hatched chick tissues. ...
Agus D B - - 1997
Vitamin C concentrations in the brain exceed those in blood by 10-fold. In both tissues, the vitamin is present primarily in the reduced form, ascorbic acid. We identified the chemical form of vitamin C that readily crosses the blood-brain barrier, and the mechanism of this process. Ascorbic acid was not ...
Umesono Y - - 1997
To analyze the organization of planarian brain, a homolog of the homeobox-containing gene Orthopedia (Otp) from planarian, Djotp, was isolated. The homeodomain of Djotp differs from mouse Otp by only two amino acids. This conservation extends to include a 12 amino acid motif downstream of the homeodomain. Whole mount in ...
Fowler C J - - 1997
The ability of rat brain (minus cerebellum) homogenates to deamidate arachidonyl ethanolamide (anandamide) was determined with a custom-synthesized substrate, arachidonyl ethanolamide-[1-3H] ([3H]anandamide). Conditions whereby initial velocities were measured were established. The homogenates deamidated anandamide with a Km value of 0.8 microM and a Vmax value of 1.73 nmol . (mg ...
Wajner M - - 1997
Methylmalonic acidaemia is an inherited metabolic disorder caused by a severe deficiency of the activity of the enzyme L-methylmalonyl-CoA mutase or its cofactor 5'-deoxyadenosylcobalamin, resulting in tissue accumulation of large quantities of methylmalonic acid. Among the various clinical features, neurological symptoms are frequently observed. Patients may present cerebral atrophy and ...
Layton M E - - 1997
Delayed tissue damage is proposed to be caused by reactive oxygen species. We investigated the effects of microdialysis probe penetration into rat piriform cortex on hydrogen peroxide (H2O2) in brain extracellular fluid (ECF). H2O2 decreased immediately after probe insertion into the brain, but increased over 300% in samples within minutes ...
Bisogno T - - 1997
Cis-9,10-octadecenoamide (oleamide) was isolated from the cerebrospinal fluid of sleep-deprived mammals and shown to induce sleep in rats. The enzyme catalyzing the hydrolysis of the amide bond of oleamide as well as of anandamide, the putative endogenous ligand of cannabinoid receptors, was purified from rat liver, cloned, shown to be ...
van der Stelt M - - 1997
As yet, the physiological significance of hydroxylation of anandamide and linoleoyl amides is unknown. Therefore, we investigated whether hydroxylation of ODNHEtOH and ODNH2 influences their binding abilities to the CB-1 receptor and whether it alters their reactivity towards a fatty acid amide hydrolase (FAAH) from rat brain. Neither the fatty ...
Deep P - - 1997
The biological accuracy of a nonlinear compartmental model describing the in vivo kinetics of L-3,4-dihydroxy-6-[18F]fluorophenylalanine ([18F]FDOPA) metabolism was investigated. Tissue activities for [18F]FDOPA and its labeled metabolites 3-O-methyl-[18F]FDOPA ([18F]OMFD), 6-[18F]fluorodopamine ([18F]FDA), L-3,4-dihydroxy-6-[18F]fluorophenylacetic acid ([18F]FDOPAC), and 6-[18F]fluorohomovanillic acid ([18F]FHVA) were calculated using a plasma [18F]FDOPA input function, and kinetic constants estimated ...
Thoresen M - - 1997
Hypoxia-ischaemia produces permanent brain damage by processes that continue for many hours after reoxygenation/reperfusion. This provides a window of opportunity for therapy aimed at preventing further loss of brain cells. Reducing brain temperature by 2-6 degrees C for 3-72 h after reoxygenation/reperfusion has been shown to reduce brain damage by ...
Lombardi V - - 1997
1. The high-resolution 1H NMR (MRS) spectra of human brain tumor homogenates revealed a broad resonance at 5.3-5.4 ppm in glioblastoma multiforme (N = 16) and brain metastases (N = 3). The broad resonance was identified as ceramide, a sphingosine-fatty acid combination portion of ganglioside, indicating an elevated abundance of ...
Kim K S - - 1997
The effect of feeding rats for 30 days with diets containing high levels of linoleic acid (sunflower oil, SO) or alpha-linolenic acid (perilla oil, PO) was studied in the liver, kidney and brain. The PO group showed a higher labeling of choline glycerophospholipids (CGP) in liver and kidney but no ...
Chen S - - 1997
The anti-morphine peptide from canine brain, which is homologous to alpha subunit of hemoglobin of canine, has been isolated and characterized. The canine brain was homogenized and extracted in 0.1 M acetic acid. The supernatant was collected, and purified by chromatography of Sephadex G-50 and ion-exchange and RP-HPLC. A polypeptide ...
Yamazaki K - - 1997
Fatty acid ethylesters (FAEE) are synthesized from ethanol and fatty acids in the heart and brain. Similarly fatty acid methylesters (FAME) are synthesized from methanol and fatty acids. Whereas methanol reportedly indicates recent or chronic consumption of alcoholic beverages, an elevated serum methanol concentration (SMC) indicates mainly chronic alcohol intake. ...
Kintner D B - - 1997
The Pulsinelli-Brierley four-vessel occlusion model was used to study the consequences of hyperglycemic ischemia and reperfusion. Rats were subjected to either 30 min of normo- or hyperglycemic ischemia or 30 min of normo- or hyperglycemic ischemia followed by 60 min of reperfusion. In some animals, 2 mg/kg BN 50739, a ...
Yudkoff M - - 1997
The synthesis of brain glutamate requires an amino group donor that is efficiently transported into the brain and that is readily transaminated. The branched-chain amino acids (BCAA), particularly leucine, play this important role. The uptake of leucine across the blood-brain barrier is faster than any other amino acid. Studies with ...
al-Sarraf H - - 1997
Using a bilateral in situ brain perfusion technique, the rate of influx of the acidic amino acids, aspartate and glutamate, into both brain and CSF, were measured in the rat. The kinetic constants for uptake of these amino acids across the blood-brain and blood-CSF barriers in neonatal (1-week-old) and adult ...
Sechi G - - 1997
Effects of pentylenetetrazole (PTZ)-induced convulsive status epilepticus on free amino acids changes in venous blood, CSF and interstitial fluid (IF) of the brain were examined in dogs. A volume of brain IF sufficient for analysis was obtained by chronically implanted tissue cages. The onset of PTZ-induced convulsive seizures seemed mainly ...
Modha A - - 1997
The Meriones unguiculatus-Echinococcus multilocularis host-parasite system was used to evaluate changes in metabolite levels in the brain of the infected host. Nuclear magnetic resonance analysis of perchloric acid extracts of the entire brain of jirds revealed that infection caused a change in the concentration of several metabolites, especially those that ...
van der Stelt M - - 1997
Anandamide, a novel neurotransmitter, has been reported to be dioxygenated by brain lipoxygenase [1,11]. Anandamides constitute a new class of neuroregulatory fatty acid amides. However, little is known about the enzymatic dioxygenation of these lipids. Therefore, we have tested several members of the neuroactive fatty acid amide class containing a ...
Jumpsen J A - - 1997
Brain development was examined in the neonatal rat in response to feeding increased levels of 18:3n - 3, 20:4n - 6 or 22:6n - 3 at levels proposed for infant formula. Diets varying in n - 6 to n - 3 fatty acid ratio, with or without 20:4n - 6 ...
Homayoun P - - 1997
Lipid second messengers such as arachidonic acid and its metabolites and diacylglycerols (DAGs) are affected in brain injury. Therefore, changes in the pool size and the fatty acid composition of free fatty acids (FFAs) and DAGs were analyzed in different rat brain areas 4 and 35 days after traumatic injury. ...
Fontana M - - 1997
The sulfur containing imino acids cystathionine ketimine (CK) and lanthionine ketimine (LK) have been detected in the human brain by an HPLC procedure. The HPLC procedure takes advantage of the selective absorbance at 380 nm of the phenylisothiocyanate-ketimine adduct. Quantitation of cystathionine ketimine and lanthionine ketimine indicates a mean concentration ...
Yehuda S - - 1997
This study examined the possible effects of a novel mixture of fatty acids, SR-3 (a specific ratio of alpha-linolenic acids), on brain biochemistry and on learning deficits induced by injection of an agent that induces experimental allergic encephalomyelitis. Treatment with SR-3 caused a decrease in myelin and changes in the ...
Nakamura K - - 1997
Eighteen gangliosides were isolated from dogfish (Squalus acanthias) brain, and their structures and compositions were determined by methylation analysis, enzymatic hydrolysis and partial hydrolysis with mild acid. Tetra- and pentasialogangliosides were also analysed by liquid secondary ion mass spectrometry. The dogfish brain gangliosides were characterized by a variety of molecular ...
Das S K - - 1997
A wide spectrum of developmental profiles is presented for a few important neurotransmitter amino acids, namely gamma-aminobutyric acid, glycine, glutamic acid, aspartic acid and taurine as well as the key enzymes involved in their metabolism in human fetal brains of different gestational ages. Besides taurine almost all these amino acids ...
Pfister H W - - 1997
Recent in-vitro studies have improved our understanding of how bacteria interact with cerebral endothelial cells and cross the blood-brain barrier. Several animal studies using rat and rabbit models of bacterial meningitis have revealed mediators of inflammation that are believed to play a key role in secondary brain damage, including reactive ...
Bolkenius F N - - 1997
Peptidylglycine alpha-hydroxylating monooxygenase (PHM; EC 1.14.17.3) catalyses the rate-limiting step in the post-translational activation of substance P, among other neuropeptides, from its glycine-extended precursor. Comparative kinetic studies were performed, using trans-styrylacetic acid or trans-styrylthioacetic acid as known mechanism-based inhibitors, of PHM isolated from rat, horse or human blood serum. Distinctive ...
Rapoport S I - - 1997
An in vivo method is presented that allows quantification and imaging of fatty acid incorporation into different brain phospholipids in relation to membrane synthesis, neuroplasticity, and signal transduction. The method can be used with positron emission tomography, and may help to evaluate brain phospholipid metabolism in humans with brain tumors, ...
Smith A J - - 1997
Pregnenolone and dehydroepiandrosterone and their sulphate and fatty acid ester derivatives are concentrated in the mammalian brain, as compared to the peripheral organs. Although biological functions have been postulated for the free steroid and sulphate conjugates, the role of steroid fatty acid esters in the central nervous system (CNS) has ...
Thomas S A - - 1997
[D-Ala2]deltorphins are enzymatically stable, amphibian heptapeptides that have a higher affinity and selectivity for delta-opioid receptors than any endogenous mammalian compound known. This study investigated the in vitro blood-brain barrier permeability, using primary bovine brain microvessel endothelium culture, and the resistance to enzymatic degradation, in mouse 15% brain membrane homogenates ...
Scapecchi S - - 1997
Molecular modification of the potent and selective muscarinic antagonist 2-ethylthio-2,2-diphenylacetic acid N,N-diethylaminoethyl ester was performed in order to identify M2 selective antagonists able to cross the blood brain barrier and potentially useful in the treatment of Alzheimer's disease. Modifications included substitution or hydrogenation of one of the phenyl rings as ...
Appel N M - - 1997
Parenterally administered domoic acid, a structural analog of the excitatory amino acids glutamic acid and kainic acid, has specific effects on brain histology in rats, as measured using different anatomic markers. Domoic acid-induced convulsions affects limbic structures such as hippocampus and entorhinal cortex, and different anatomic markers can detect these ...
Burth P - - 1997
We showed previously that the glycolipoprotein fraction prepared from Leptospira interrogans inhibited the Na+,K+ ATPase enzyme purified from brain or kidney and in isolated nephron segments (M. Younes-Ibrahim, P. Burth, M. V. Castro Faria, B. Buffin-Meyer, S. Marsy, C. Barlet-Bas, L. Cheval, and A. Doucet, C. R. Acad. Sci. Paris ...
Appel N M - - 1997
Brain damage following administration of domoic acid, a structural analog of the excitatory amino acids glutamic acid and kainic acid, was compared using different anatomic markers in adult rats. Seven days after administration of domoic acid (2.25 mg/kg i.p.) or vehicle, brains were collected and sectioned and stained to visualize ...
Schieber A - - 1997
Sprague-Dawley rats received deionized water (controls) during 28 days or drinking water with added D-proline, L-proline, D-aspartic acid or L-aspartic acid corresponding to a mean daily load of approximately 50 mg amino acid enantiomer kg-1 body weight. Parameters indicating the physiological status (food intake and body weight, glutamic-oxalic-transaminase, glutamic-pyruvic-transaminase, alkaline ...
Hamase K - - 1997
Regional distribution of D-amino acids in rat brain was studied by the modified highly sensitive analytical method which was previously developed. The method includes fluorogenic derivatization of each amino acid, isolation of each amino acid by reverse-phase HPLC, followed by enantiomeric separation with Pirkle-type chiral stationary phases. D-Amino acid contents ...
Eriksson T - - 1997
BACKGROUND: Aggression has been suggested to be related to abnormal brain 5-HT activity. This amine is synthesized in brain from tryptophan, which is transported through the blood-brain barrier in competition with other amino acids. The relationship between tryptophan and its endogenous amino acid competitors in plasma might thus influence the ...
Stancampiano R - - 1997
The effect of oral administration of a tryptophan-free amino acid mixture or the same mixture containing tryptophan (Trp) on hippocampal serotonin (5-HT) extracellular levels was studied using in vivo brain microdialysis of freely moving rats. During chloral hydrate anesthesia rats were implanted with dialysis probes in the dorsal hippocampus, and ...
Flor P J - - 1997
Two splice variants of the human metabotropic glutamate receptor 7, named hmGluR7a and hmGluR7b, were isolated from a human brain cDNA library. The isoforms differ by an out-of-frame insertion of 92 nucleotides close to the C-terminus of the hmGluR7 coding region, hmGluR7a has a length of 915 amino acids and ...
Taketomi T - - 1997
Our rapid method of microwave-mediated saponification for preparing lysoglycosphingolipids from their parent glycosphingolipids was also able to prepare lysogangliosides or modified lysogangliosides, which were identified by delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometric (DE MALDI-TOF MS) analysis. When GM3, GM2, and GM1 isolated from adult human brain gangliosides ...
Cunnane S C - - 1997
Our objective was to develop a suitable probe to study metabolism of polyunsaturated fatty acids by 13C nuclear magnetic resonance (NMR) in the suckling rat pup. [3-13C] gamma-Linolenic acid was chemically synthesized, and a 20 mg (Experiment 1) or 5 mg (Experiment 2) dose was injected into the stomachs of ...
Packer L - - 1997
Reactive oxygen species are thought to be involved in a number of types of acute and chronic pathologic conditions in the brain and neural tissue. The metabolic antioxidant alpha-lipoate (thioctic acid, 1, 2-dithiolane-3-pentanoic acid; 1, 2-dithiolane-3 valeric acid; and 6, 8-dithiooctanoic acid) is a low molecular weight substance that is ...
Roser W - - 1997
A patient with AL (amyloid light chain) amyloidosis was investigated in liver and brain by localized magnetic resonance spectroscopy. Liver spectra of the patient were characterized by small line widths, a striking increase of trimethylammonium compounds, and the presence of a further resonance at 3.8 ppm. None of the healthy ...
Dasgupta S - - 1997
Developmental expression of neutral monoglycosylceramides (MGCs) has been examined in rat brain from embryonic day 15 (E15) to postnatal day 30 (P30) and adulthood. To this point, glucosylceramide (GlcCer) is the only MGC that has been characterized in embryonic brain. Galactosylceramide (GalCer) appears at P1, increases with age until P25 ...
Imai K - - 1997
Reports on the distribution, metabolism and origins of free D-amino acids in vertebrate tissues and body fluids are reviewed. The transient emergence of D-aspartic acid during the development of brain and peripheral organs or early stages of life is reported. D-Serine in brain is postulated to be a potentiator for ...
Bolaños J P - - 1997
The effects of valproate on brain energy and lipid metabolism is reviewed. Increasing evidence suggests that valproate uses the monocarboxylic acid carrier in order to cross the blood brain barrier (BBB) and the neural cell plasma membranes. The uptake of valproate into the brain through this mechanism would compete with ...
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