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Deng Wei-Wei - - 2009
We examined the distribution of ethylamine, glutamic acid and alanine, which are utilized in theanine biosynthesis, and other major amino acids in leaves, stems, cotyledons and roots of 6-week-old tea seedlings. Ethylamine and glutamic acid, which are substrates of theanine synthetase, were distributed almost uniformly in all parts of the ...
Valentine Gerald W - - 2009
Accumulating evidence indicates that dysfunction in amino acid neurotransmission contributes to the pathophysiology of depression. Consequently, the modulation of amino acid neurotransmission represents a new strategy for antidepressant development. While glutamate receptor ligands are known to have antidepressant effects, mechanisms regulating glutamate cycling and metabolism may be viable drug targets ...
Wieraszko A - - 2009
Segments of the mouse sciatic nerve were preloaded with either d-2,3-(3)H-Aspartic acid [nonmetabolizable analog of glutamate] or l-(14)C-proline and the release of these exogenous molecules was evaluated in the fractions of the perfusate following electrical or magnetic stimulation. The electrical stimulation (10Hz, 10Am, 20s) induced an instantaneous increase in the ...
Venturini A - - 2009
Taurine, glutamine, glutamate, aspartate, and alanine are the most abundant intracellular free amino acids in human heart. The myocardial concentration of these amino acids changes during ischemia and reperfusion due to alterations in metabolic and ionic homeostasis. We hypothesized that dilated left ventricle secondary to mitral valve disease has different ...
Jo Sung-Jin - - 2009
We previously synthesized poly(3-hydroxybutyrate) [P(3HB)] in recombinant Corynebacterium glutamicum, a prominent producer of amino acids. In this study, a two-step cultivation was established for the dual production of glutamate and P(3HB) due to the differences in the optimal concentration of biotin. Glutamate was extracellularly produced first under the biotin-limited condition ...
Benveniste Helene - - 2009
Elevation of the extracellular concentrations of glutamate and aspartate in rat hippocampus during transient cerebral ischemia monitored by intracerebral microdialysis. By Helene Benveniste, Jørgen Drejer, Arne Schousboe, Nils H. Diemer. J Neurochem 1984; 43:1369-74. Reprinted with permission of Blackwell Publishing. Rats were implanted with 0.3-mm-diameter dialysis tubing through the hippocampus ...
Lopicic Srdjan - - 2009
In this paper we examine the effects of L-aspartate, L-glutamate, and beta-N-oxalylamino-L-alanine (Lathyrus toxin) on Retzius nerve cells of the leech Haemopis sanguisuga. The goal was to compare the electrophysiological effects of endogenous vs. exogenous amino acids, known as potent neurotoxins, through the mechanism ofexcitotoxicity. We used classical intracellular recordings ...
Stockhammer Florian - - 2009
AIMS: Oligodendroglial tumours with loss of heterozygosity on 1p (LOH1p) respond better to treatment than oligodendrogliomas without LOH. Previous reports have assigned a crucial role of glutamate metabolism to glioma growth and invasion. The aim was to study the protein expression of different glutamate transporters in relation to LOH1p in ...
Kim Mi Kyoung - - 2009
In order to discover a quercetin prodrug with improved bioavailability, we synthesized nine quercetin-amion acid conjugates and estimated their pharmacokinetic properties including water solubility, stability against chemical or enzymatic hydrolysis, and cell permeability. Among the synthesized quercetin prodrugs, quercetin-glutamic acid conjugate Qu-E (4g/5g) showed remarkable increases in water solubility, stability, ...
Wu Jun-liang - - 2009
This study focuses on the role of amino acids in xylem sap of tomato grown in hydroponics in a medium supplemented with a series of concentration of La and Y. Eighteen amino acids in xylem saps were identified and measured by reversed-phase high-performance liquid chromatography. The main amino acids in ...
Lee Su-Ui - - 2010
We found that camphoric acid significantly stimulated the differentiation of mouse osteoblastic MC3T3-E1 subclone 4 cells, as indicated by the induction of markers of osteoblastic differentiation. To elucidate the mechanism of action of camphoric acid in osteoblast differentiation, we evaluated the induction of transient receptor potential (TRP) cation channel family ...
Bajaj Ishwar B - - 2009
The aim of the present work was to study the effect of addition of different amino acids and tricarboxylic acid cycle intermediates as metabolic precursors on the production of poly (gamma-glutamic acid) (PGA) by Bacillus licheniformis NCIM 2324. A maximum yield of 35.75 g/l was obtained with the medium supplemented ...
Pham Ngoc-Thi - - 2008
To clarify the involvement of excitatory and inhibitory amino acids in canine necrotizing meningoencephalitis (NME), glutamate, aspartate, taurine and gamma-aminobutylic acid (GABA) were determined in the cerebrospinal fluids (CSF) from eight NME cases and ten healthy controls. NME dogs exhibited significantly higher concentrations of glutamate and aspartate than those in ...
Ahmed Nawal Abd El Hay - - 2008
OBJECTIVE: The aim of this study is to investigate the effects of three different intensities of infrared diode laser radiation on amino acid neurotransmitters in the cortex and hippocampus of rat brain. BACKGROUND DATA: Lasers are known to induce different neurological effects such as pain relief, anesthesia, and neurosuppressive effects; ...
Miyashita Yo - - 2008
Glutamate is of central importance in plant N metabolism since the biosynthesis of all other amino acids requires this compound. Glutamate dehydrogenase (GDH; EC 1.4.1.2), which catalyzes in vitro reversible reductive amination of 2-oxoglutatre to form glutamate, is a key player in the metabolism of glutamate. While most previous studies ...
Zhao Min - - 2008
There is evidence that isoprostanes (IsoPs) can regulate exogenously applied excitatory amino acid neurotransmitters in bovine retina in vitro. However, the regulation of retinal morphology and endogenous neurotransmitter levels by IsoPs is unknown. We examined the effects of intravitreally injected 8-iso-PGE(2) on retinal tissue integrity and viability and amino acid ...
Meng Ling - - 2009
A glutamate biosensor based on the electrocatalytic oxidation of reduced nicotinamide adenine dinucleotide (NADH), which was generated by the enzymatic reaction, was developed via employing a single-walled carbon nanotubes/thionine (Th-SWNTs) nanocomposite as a mediator and an enzyme immobilization matrix. The biosensor, which was fabricated by immobilizing glutamate dehydrogenase (GlDH) on ...
Hamann M - - 2008
The pathophysiology of idiopathic dystonia is still unknown, but it is regarded as a basal ganglia disorder. Previous studies indicated an involvement of a striatal GABAergic disinhibition and a cortico-striatal glutamatergic overactivity in the manifestation of stress-inducible dystonic episodes in the dt(sz) hamster, a model of idiopathic paroxysmal dystonia. These ...
Quang Dang Ngoc - - 2008
Three novel alkaloids (1-3), named pyriferines A-C, were isolated from fruiting bodies of Pseudobaeospora pyrifera. They possess an unusual eight-membered N/O-acetal ring, derived from L-glutamic acid, that is connected to an enolized 1,3-diketo moiety. The structures were determined by spectroscopic methods, and the absolute configuration of the glutamic acid moiety ...
Carranza Yaneth E - - 2008
Chondroitin-4-sulfate was oversulfated using chlorosulfonic acid-pyridine complex and was isolated as the sodium salt. A comparison of the infrared analysis of the native (N-2) and oversulfated (S-2) compounds showed that the two spectra were identical except for a new peak in S-2 at 825 cm corresponding to the equatorial C-6 ...
Colgrave Michelle L - - 2008
The cyclotides are a family of backbone-cyclised cystine-knot-containing peptides from plants that possess anthelmintic activity against Haemonchus contortus and Trichostrongylus colubriformis, two important gastrointestinal nematode parasites of sheep. In the current study, we investigated the in vitro effects of newly discovered natural cyclotides on the viability of larval and adult ...
Miyaji Takaaki - - 2008
Aspartate is an excitatory amino acid that is costored with glutamate in synaptic vesicles of hippocampal neurons and synaptic-like microvesicles (SLMVs) of pinealocytes and is exocytosed and stimulates neighboring cells by binding to specific cell receptors. Although evidence increasingly supports the occurrence of aspartergic neurotransmission, this process is still debated ...
Fournier Francoise - - 2008
The gas-phase acidities of aspartic, glutamic, and 2-aminoadipic acid have been determined by the kinetic method in a triple-quadrupole instrument. Although aspartic acid behaves in the conventional way and gives a DeltaH(acid) value of 1340 kJ mol(-1), glutamic and 2-aminoadipic acids give kinetic method plots with two distinct slopes. This ...
Osborne Peter G - - 2008
This report demonstrates that during the torpor phase of hibernation, hamsters utilize (14)C and (13)C glucose in torpor-specific brain metabolic pathways. Microdialysis of (14)C glucose into the striatum rapidly induced a steady state labeling of extracellular fluid (ECF) lactate and labeling of tissue GABA, glutamate, glutamine, and alanine in ipsilateral ...
Potrykus Joanna - - 2008
The butyrate-producing anaerobe Fusobacterium varium is an integral constituent of human gut microflora. Unlike many gut microorganisms, F. varium is capable of fermenting both amino acids and glucose. Although F. varium has been implicated in beneficial as well as pathological bacterium-host interactions, its genome has not been sequenced. To obtain ...
Clauwaert Peter - - 2008
Two types of rapidly biodegradable vegetable products (the liquid fraction of clover and the glycerol-containing sidestream from biodiesel production) were selected for anodic oxidation in microbial fuel cells (MFC) equipped with a biocathode. As benchmark references, five abundant amino-acids in plant sap (L: -glutamine, L: -glutamic acid, L: -asparagine, L: ...
Witt Anna C - - 2008
Human DJ-1, a disease-associated protein that protects cells from oxidative stress, contains an oxidation-sensitive cysteine (C106) that is essential for its cytoprotective activity. The origin of C106 reactivity is obscure, due in part to the absence of an experimentally determined p K a value for this residue. We have used ...
Rufino Raquel D - - 2008
The strategy of optimization using sequential factorial design was employed to enhance the tensio-active emulsifying agent produced by Candida lipolytica using soybean oil refinery residue as substrate. A full factorial design was used to evaluate the impact of three fermentation factors-amounts of refinery residue, glutamic acid and yeast extract. This ...
Jean Y-H - - 2008
OBJECTIVE: The present study aimed to determine the role of excitatory amino acids (EAAs) and EAA transporters (EAATs) in an osteoarthritis (OA) model of rabbit knees. METHODS: OA was induced in New Zealand white male rabbits by anterior cruciate ligament transection (ACLT) in one knee of one hind limb; the ...
Bogen Inger Lise - - 2008
The relations between glutamate and GABA concentrations and synaptic vesicle density in nerve terminals were examined in an animal model with 40-50% reduction in synaptic vesicle numbers caused by inactivation of the genes encoding synapsin I and II. Concentrations and synthesis of amino acids were measured in extracts from cerebrum ...
Wang Fei - - 2008
Poly(gamma-glutamic acid) (PGA) produced by a strain of Bacillus subtilis was partially hydrolyzed into various oligopeptides so that the dipeptide fraction was isolated by the preparative thin-layer chromatography. HPLC analysis was applied to the detection of each of the four stereoisomers in this fraction using chemically synthesized authentic samples. The ...
Ballini Chiara - - 2008
The extracellular levels of aspartate, glutamate and GABA were measured by microdialysis, coupled with an HPLC method, in rat prefrontal cortex (mPFC) and ventral hippocampus (VH) before and during the performance of a step-down inhibitory task. The basal levels of glutamate were about 50% higher than those of aspartate, and ...
Colleoni Simona - - 2008
(+/-)-3-Hydroxy-4,5,6,6a-tetrahydro-3aH-pyrrolo [3,4 -d]-isoxazole-4-carboxylic acid (HIP-A) and (+/-)-3-hydroxy-4,5,6, 6a-tetrahydro-3aH-pyrrolo[3,4-d]isoxazole-6-carboxylic acid (HIP-B) are selective inhibitors of excitatory amino acid transporters (EAATs), as potent as DL-threo-beta-benzyloxyaspartic acid (TBOA). We report here that the active isomers are (-)-HIP-A and (+)-HIP-B, being approximately 150- and 10-fold more potent than the corresponding enantiomers as inhibitors of ...
Viola Ronald E - - 2008
It is established that cells of Yersinia pestis, the causative agent of bubonic plague, excrete l-aspartic acid at the expense of exogenous l-glutamic acid during expression of the low-calcium response. Results of enzymic analysis provided here suggest that a previously defined deficiency of aspartase (AspA) accounts for this phenomenon rather ...
Lee Sang Hak - - 2008
A flow injection chemiluminescence (CL) determination of aspartic acid is described. In this work, it was observed that aspartic acid could enhance the chemiluminescence (CL) emission of Ru(bipy)3(2+)-Ce(IV) system and this enhancement effect was dependent on the concentration of aspartic acid, based on which, CL system was established for the ...
Waagepetersen Helle S - - 2008
Mouse cerebral cortical mini-slices were used in a superfusion system to monitor depolarization-induced (55 mM K(+)) release of preloaded [2,3-(3)H]GABA and to investigate the biosynthesis of glutamate, GABA and aspartate during physiological and depolarizing (55 mM K(+)) conditions from either [1,6-(13)C]glucose or [U-(13)C]glutamine. Depolarization-induced GABA release could be reduced (50%) ...
Guccione Edward - - 2008
Amino acids are key carbon and energy sources for the asaccharolytic food-borne human pathogen Campylobacter jejuni. During microaerobic growth in amino acid rich complex media, aspartate, glutamate, proline and serine are the only amino acids significantly utilized by strain NCTC 11168. The catabolism of aspartate and glutamate was investigated. An ...
Navarro Darren - - 2008
Thiamine deficiency provides an effective model of selective neuronal cell death. (1)H and (13)C-NMR was used to investigate the effects of thiamine deficiency on the synthesis of amino acids derived from [1-(13)C]glucose in vulnerable (medial thalamus; MT) compared to non-vulnerable (frontal cortex; FC) brain regions. Following 11 days of thiamine ...
Jankovic Slobodan M - - 2009
OBJECTIVES: A neurotransmitter role for glutamate in the autonomous nervous system was recently demonstrated in the gastrointestinal tract, and its stimulatory effect on spontaneous motility of human ureter was shown. The aim of our study was to investigate the effects of glutamate on the release of neurotransmitters from intramural nerves ...
Conti Paola - - 2008
Chiral pyrazoline amino acids (3aR,4S,6aR)-1a and (3aR,4S,6aR)-1b, and (3aS,6S,6aS)-2a and (3aS,6S,6aS)-2b, which are conformationally constrained analogues of glutamic and homoglutamic acid, respectively, were prepared via a strategy based on the 1,3-dipolar cycloaddition of a nitrile imine to methyl N-Boc-3,4-didehydro-(S)-prolinate. The new 'amino acids' were tested for activity at ionotropic glutamate ...
Jantzie Lauren L - - 2008
BACKGROUND: Neonatal hypoxia-ischemia (HI) is a common complication of pregnancy and delivery. Conventional clinical practice is to resuscitate neonates with 100% O2, and evidence is building to suggest resuscitation with lower O2 concentrations is safer. Significant neurochemical changes are associated with HI injury and persistent changes in amino acids are ...
Glodzik Lidia - - 2008
Glutamate (Glu) is associated with excitotoxic cell damage. Memantine modulates the glutamate induced excitotoxicity in Alzheimer's disease (AD). No information is available as to the influence of memantine on in vivo brain glutamate levels. Hippocampal Glu levels were measured in cognitively impaired and normal individuals (n=10) before and after 6 ...
Ohtani Susumu - - 2008
In slowly metabolizing tissue such as tooth, bone and ocular lens, D-amino acids converted from L-amino acids accumulate with age and thus reflect the tissue turnover rate. To investigate whether D-amino acids play a role in determining the bone remodeling rate, we measured the accumulation of D-aspartic acid, which has ...
Godfrey D A - - 2008
Using a microchemical approach, we measured changes of amino acid concentrations in the chinchilla caudal posteroventral cochlear nucleus (PVCN) after cochlear ablation to determine to what extent slow decreases of glutamate and aspartate concentrations after carboplatin treatment resulted from slower effects of cochlear damage in chinchillas than in rats and ...
Alberto D - - 2008
Current peaks have been observed and measured in electrolytic ionic current of L-glutamic acid aqueous solutions at room temperature, in static magnetic fields of 20, 40, and 60 muT flux densities, with a superimposed extremely low-frequency, (1/10) Hz, alternating magnetic field flux density of 40 nT. The distributions of the ...
Levrat Virginie V Centre de référence Maladies Héréditaires du Métabolisme, Service de Pédiatrie, Hôpital Edouard Herriot, Lyon, France. - - 2008
Hyperammonemia in patients with methylmalonic aciduria (MMA) and propionic aciduria (PA) is caused by accumulation of propionyl-CoA which decreases the synthesis of N-acetyl-glutamate, the natural activator of carbamyl phosphate synthetase 1. A treatment approach with carglumic acid, the structural analogue of N-acetyl-glutamate, has been proposed to decrease high ammonia levels ...
Oppedisano Francesca - - 2007
The glutamine/amino acid transporter solubilized from rat renal apical plasma membrane (brush-border membrane) with C12E8 and reconstituted into liposomes has been previously identified as the ASCT2 transporter. The reconstituted transporter catalyses an antiport reaction in which extraliposomal glutamine and Na+ are cotransported in exchange with intraliposomal neutral amino acids. Differently ...
Uffmann Kai - - 2007
A novel approach for the mathematical modeling of (13)C label incorporation into amino acids via the TCA cycle that eliminates the explicit calculation of the labeling of the TCA cycle intermediates is described, resulting in one differential equation per measurable time course of labeled amino acid. The equations demonstrate that ...
Bak Lasse K - - 2007
Glutamate homeostasis during glutamatergic neurotransmission is predominantly maintained via functioning of the glutamate-glutamine cycle. However, the glutamate-glutamine cycle explains only the fate of the carbon atoms but not that of the accompanying transfer of nitrogen from neurons to astrocytes. In this respect, a putative branched-chain amino acid (BCAA) shuttle has ...
Adams A L - - 2008
Altered functioning of the glutamate system during critical periods of development is believed to play a role in various neurodevelopmental disorders, such as schizophrenia. Prepulse inhibition (PPI) of the acoustic startle response is deficient in people with schizophrenia. This study investigated the theory that neonatal treatment with domoic acid (DOM), ...
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