Search results for "Glutamates"
showing 10 items of 27 documents
Swelling of glial cells in lactacidosis and by glutamate: significance of Cl(-)-transport.
1993
Swelling of glial and nerve cells is characteristic of brain damage in cerebral ischemia or trauma. The therapeutical efficiency of inhibition of Cl(-)-transport by a novel antagonist, the diuretic torasemide, on cytotoxic swelling of glial cells from lactacidosis, or glutamate was analyzed. Lactacidosis and the interstitial accumulation of glutamate are hallmarks of the pathophysiological alterations in ischemic or traumatic brain tissue. C6 glioma cells harvested from culture and suspended in a physiological medium were either exposed to pH 6.2, or 5.0 by lactic acid, or exposed to 1 mM glutamate at normal pH. Cell swelling and viability were quantified by flow cytometry. Lactacidosis of …
l-Glutamate receptor binding in bovine retina
1982
Using a centrifugation technique saturable specific [ 3 H]glutamate binding in bovine retina could be demonstrated. Scatchard analysis revealed only one population of binding sites with a dissociation constant of about 3 μ m and a maximal number of binding sites of about 0·2 pmol/mg retinal protein. Several glutamic acid analogues inhibit specific [ 3 H]glutamate binding in bovine retina with half-maximal inhibitory concentrations similar to those reported in other areas of the CNS. Specific [ 3 H]glutamate binding and sodium dependent synaptosomal uptake of glutamate are largely concentrated in the P2 fraction of bovine retina homogenates consisting of conventionally sized synaptosomes. Th…
N-acetyl-L-glutamate in brain: assay, levels, and regional and subcellular distribution.
1991
N-Acetyl-L-glutamate (NAG), the activator of mitochondrial carbamoyl phosphate synthetase (CPS), is demonstrated by several methods, including a new HPLC assay, in the brain of mammals and of chicken. The brain levels of NAG are 200-300 times lower than the levels of N-acetyl-L-aspartate (NAA), and are similar to the levels of NAG in rat liver. The NAG levels in chicken liver are very low. Although NAG is mitochondrial in the liver, it is cytosolic in brain. Using enzyme activity and immuno assays we did not detect CPS in brain (detection limit, 12.5 micrograms/g brain), excluding that brain NAG is involved in citrullinogenesis. The regional distribution of brain NAG differs from that of NA…
Pharmacological intervention in age-associated brain disorders by Flupirtine: Alzheimer’s and Prion diseases
1998
Alzheimer's disease, a major form of dementia in the elderly has become an increasingly important health problem in developed countries. In vitro studies on primary neurons demonstrate that Flupirtine (Katadolon) at a concentration of 1 microg/ml, significantly reduces the neurotoxic (apoptotic) effect displayed by A beta25-35, a segment of the amyloid beta-protein precursor the etiologic agent of Alzheimer's disease. Flupirtine, which has been in clinical use since 10 years ago, prevents the toxic effect of PrP, the presumed etiologic agent of the Creutzfeldt-Jakob disease as well as the excitatory amino acid glutamate on cortical neurons. Flupirtine displays a bimodal activity. Its strong…
Effect of Thyroid Hormones on Urea Biosynthesis and Related Processes in Rat Liver*
1988
The results of the few studies on the effect of the thyroid status on nitrogen metabolism have been inconclusive and/or contradictory. In an attempt to elucidate this important relationship, we have studied the effect of experimental hypo- and hyperthyroidism on urea biosynthesis and related processes. We have found that the capacity of the liver to synthesize urea was increased in hypothyroid rats, as were the activities of the urea cycle enzymes; there were also changes in the activities of some related enzymes and in the levels of intermediates and amino acids. Isolated hepatocytes from these rats showed an increased capacity for urea synthesis. In hyperthyroid rats the picture was more …
Implications of cysteine metabolism in the heavy metal response in Trichoderma harzianum and in three Fusarium species
2009
We studied the ability of four different fungal species, Trichoderma harzianum, Fusarium antophyllum, Fusarium compactum and Fusarium phyllophilum, to grow in the presence of heavy metals, and monitored their cysteine and glutathione content and the activity of O-acetylserine(thiol)lyase (OASTL), which is involved in cysteine biosynthesis. Zn and Pb did not affect fungal growth or sporulation at the concentrations used, whereas Cd and Hg did. In most cases, cysteine and glutathione content was higher when fungi were grown in the presence of toxic metals. As T. harzianum and F. phyllophilum presented the best growth rate on Cd and Hg, they were selected to further analyse the accumulation of…
Afatinib versus cisplatin-based chemotherapy for EGFR mutation-positive lung adenocarcinoma (LUX-Lung 3 and LUX-Lung 6): analysis of overall survival…
2015
Summary Background We aimed to assess the effect of afatinib on overall survival of patients with EGFR mutation-positive lung adenocarcinoma through an analysis of data from two open-label, randomised, phase 3 trials. Methods Previously untreated patients with EGFR mutation-positive stage IIIB or IV lung adenocarcinoma were enrolled in LUX-Lung 3 (n=345) and LUX-Lung 6 (n=364). These patients were randomly assigned in a 2:1 ratio to receive afatinib or chemotherapy (pemetrexed-cisplatin [LUX-Lung 3] or gemcitabine-cisplatin [LUX-Lung 6]), stratified by EGFR mutation (exon 19 deletion [del19], Leu858Arg, or other) and ethnic origin (LUX-Lung 3 only). We planned analyses of mature overall sur…
Distinct influence of atypical 1,4-dihydropyridine compounds in azidothymidine-induced neuro- and cardiotoxicity in mice ex vivo.
2008
This study demonstrates the effective protection by compounds of atypical 1,4-dihydropyridine (DHP) series cerebrocrast, glutapyrone and tauropyrone against neuro- and cardiotoxicity caused by the model compound azidothymidine, a well-known mitochondria-compromising anti-HIV drug. In previous in vitro experiments, we have demonstrated distinct effects of these DHP compounds to influence mitochondrial functioning. In the present in vivo experiments, DHP compounds were administered intraperitoneally in mice daily for 2 weeks, per se and in combinations with azidothymidine at doses: azidothymidine 50 mg/kg; cerebrocrast 0.1 mg/kg; glutapyrone 1 mg/kg; and tauropyrone 1 mg/kg. At the end of the…
A randomized phase II study of pemetrexed in combination with cisplatin or carboplatin as first-line therapy for patients with locally advanced or me…
2013
Abstract Background Pemetrexed plus cisplatin was approved for first-line treatment of non–small-cell lung cancer (NSCLC) in patients with nonsquamous histology after initiation of this study. This phase II study evaluated pemetrexed plus cisplatin and pemetrexed plus carboplatin as first-line treatments for stage IIIB/IV NSCLC. Patients and Methods The patients were randomized (1:1) to 2 parallel arms: pemetrexed (500 mg/m2) plus cisplatin (75 mg/m2) or pemetrexed (500 mg/m2) plus carboplatin (area under the curve 6) day 1 every 3 weeks (maximum, 6 cycles). Progression-free survival (PFS) was the primary objective; secondary objectives included overall survival (OS), 1-year survival, and s…
The Study of Carbamoyl Phosphate Synthetase 1 Deficiency Sheds Light on the Mechanism for Switching On/Off the Urea Cycle
2015
12 páginas, 4 figuras, 2 tablas.