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Results 451 - 500 of 1597
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Iwasa Motoh - - 2003
OBJECTIVE: The administration of solutions rich in branched-chain amino acids leads to mental recovery from acute hepatic encephalopathy in patients with liver cirrhosis. However, the mechanism of action of branched-chain amino acids remains unclear. The purpose of this study was to evaluate the effect of intravenous infusion of branched-chain amino ...
Verardo Giancarlo - - 2003
The composition of the surface waxes of three apple ( Malus domesticaL.) cultivars ("Florina", "Golden B" and "Ozark Gold") has been studied by means of spectroscopic and GC-MS analysis of the class-fractionated mixture of components. Odd n-alkanes, mainly C(27) and C(29) molecules, are prevalent in the saturated fraction. Small concentrations ...
Smyth M - - 2003
Bovine enterovirus (BEV), along with other enteroviruses and the rhinoviruses, has a hydrophobic pocket within structural protein VP1. In the crystal structures of these viruses there is electron density commensurate with a non-protein molecule within the pocket. These molecules, termed pocket factors, have been shown to stabilise the capsid and ...
Sebastian Aleksandra - - 2003
An integrated procedure is presented whereby gas chromatography-ion trap mass spectrometry is used to determine chemical markers of gram-negative bacterial lipopolysaccharide (3-hydroxy fatty acids with 10 to 18 carbon atoms), gram-positive bacteria (branched-chain fatty acids with 15 and 17 carbon atoms), bacterial peptidoglycan (muramic acid), and fungal biomass (ergosterol) in ...
Carballeira Néstor M - - 2003
The marine fatty acid (+/-)-9-methoxypentadecanoic acid was synthesized for the first time in seven steps (7.8% overall yield) starting from commercially available 9-decen-1-ol. The key step in the synthesis was the coupling of pentylmagnesium bromide with 1-benzyloxy-9,10-epoxydecane under 1,5-cyclooctadiene copper (I) chloride catalysis. Nuclear magnetic resonance data are provided for ...
Richardson Mary Ann - - 2003
OBJECTIVE: The efficacy of the branched-chain amino acids in the treatment of tardive dyskinesia in men with psychiatric disorders was tested. METHOD: Public-sector psychiatric patients with long histories of antipsychotic treatment and presumably long-standing tardive dyskinesia were randomly assigned to receive branched-chain amino acids or placebo. Treatment frequency was three ...
Das Undurti N - - 2003
It is proposed that long-chain polyunsaturated fatty acids when given from the perinatal period will ensure proper development and growth of the brain and maintain the activity and/or concentrations of ras, nitric oxide, insulin, and various neurotransmitters and cytokines at physiological level and thus, improve memory and prevent learning deficits.
Jansen Michael - - 2003
Zygosaccharomyces rouxii, a salt-tolerant yeast isolated from the soy sauce process, produces fusel alcohols (isoamyl alcohol, active amyl alcohol and isobutyl alcohol) from branched-chain amino acids (leucine, isoleucine and valine, respectively) via the Ehrlich pathway. Using a high-throughput screening approach in microtiter plates, we have studied the effects of pH, ...
Malago J J - - 2003
The response of intestinal epithelial cells to short-chain fatty acids, which are increasingly used as food additives, was investigated. Human small intestinal epithelial cell model Caco-2 cells were exposed to formate, propionate and butyrate to assess their effect on cellular growth, metabolism, differentiation and protection against bacteria. The Caco-2 cells ...
Chirita Carmen N - - 2003
Alzheimer's disease is defined in part by the intraneuronal accumulation of filaments comprised of the microtubule-associated protein tau. In vitro, fibrillization of recombinant tau can be induced by treatment with various agents, including phosphotransferases, polyanionic compounds, and fatty acids. Here we characterize the structural features required for the fatty acid ...
Goto Masaru - - 2003
Branched-chain amino acid aminotransferase (BCAT), which has pyridoxal 5'-phosphate as a cofactor, is a key enzyme in the biosynthetic pathway of hydrophobic amino acids (leucine, isoleucine, and valine). The enzyme reversibly catalyzes the transfer of the amino group of a hydrophobic amino acid to 2-oxoglutarate to form a 2-oxo acid ...
Baldwin Adam - - 2003
The thiocarbamates, such as pebulate (S-propyl butyl (ethyl) thiocarbamate) are a well-established class of herbicides. They inhibit fatty acid elongation, which is necessary for the biosynthesis of constituents of surface waxes and suberin and this has been proposed to be important for their toxicity. In this study lipid metabolism was ...
Heller Axel R - - 2003
Cell membranes are not simply barriers separating intracellular from extracellular space. Rather, they represent a dynamic high-turnover system that adapts to current demands. During inflammation, prostaglandins and leukotrienes are formed from membrane-derived phospholipids. Encouraging improvements in critically ill patients were observed after nutritional replacement of long-chain omega-6 fatty acids with ...
Macpherson Gordon R - - 2003
The biosynthetic origins of the diarrhetic shellfish poisoning toxins DTX-5a and DTX-5b have been elucidated by supplementing cultures of the producing organism Prorocentrum maculosum with stable isotope labeled precursors and determining the incorporation patterns by 13C NMR spectroscopy. The amino acid residue in the sulfated side chain is found to ...
Jones Patricia M - - 2003
Dietary management of long-chain l-3-hydroxyacyl CoA dehydrogenase (LCHAD) deficiency involves a regimen that contains adequate carbohydrate, protein, and essential lipids, and supplementation with medium-chain fatty acids in the form of medium-chain triglycerides, providing energy from fats that bypasses the long-chain metabolic block. This study analyzes the effects of dietary treatment ...
dos Santos Pereira Alberto - - 2003
Tipuana tipu (Benth.) Kuntze is a tree from the leguminosae family (Papilionoideae) indigenous in Argentina and extensively used in urbanism, mainly in Southern Brazil. The epicuticular waxes of leaves and branch, and flower surface were studied by high temperature high resolution gas chromatography. Several compounds were characterized, among which the ...
Lalah J O - - 2003
The branched isomers of p-nonylphenol (NP) are perceived to be more resistant to biodegradation in aquatic environments as well as to have more estrogen-like toxicity than the straight chain isomers. By use of GC-MS, some of them have been identified and found to exist in higher concentrations in the isomeric ...
Andrade Claudia M B - - 2003
Sphingolipids play a relevant role in cell-cell interaction, communication, and migration. We studied the sphingolipid content in the murine hepatic stellate cell line GRX, which expresses the myofibroblast phenotype, and can be induced in vitro to display the fat-storing phenotype. Lipid modifications along this induction were investigated by labeling sphingolipids ...
Kurz Michael - - 2003
Ustilago species produce an extracellular oil that shows activity in various pharmaceutical assays. We isolated several complexes of this heterogeneous glycolipid from cultures of Ustilago maydis DSM 11494 and Geotrichum candidum ST 002515, and determined the chemical structures of these new compounds, termed ustilipids, on the basis of NMR experiments, ...
Vermeer Cornelia P - - 2003
Surface extracts from primary leaves of Castor bean were found to contain 1.8 microg cm(-2) of cuticular waxes. The mixture comprised alkanes (C(26)-C(29)), primary alcohols (C(22)-C(38)), aldehydes (C(26) and C(28)), fatty acids (C(20)-C(34)) and triterpenoids (lupeol, beta- and alpha-amyrin). Besides, a series of n-alkane-1,3-diols was detected, with chain lengths ranging ...
Horst R L RL National Animal Disease Center, ARS-USDA, Ames, Iowa, USA. - - 2003
1alpha-Hydroxy-23 carboxy-24,25,26,27-tetranorvitamin D(3) (calcitroic acid) is known to be the major water-soluble metabolite produced during the deactivation of 1,25-(OH)(2)D(3). This deactivation process is carried out exclusively by the multicatalytic enzyme CYP24 and involves a series of oxidation reactions at C(24) and C(23) leading to side-chain cleavage and, ultimately, formation of ...
Brady Sean F - - 2003
[structure: see text] Long-chain fatty acid enol ester 1 is the major metabolite of a new family of small molecules isolated from the heterologous expression of environmentally derived DNA. A versatile synthesis of 1, in which an aromatic acetaldehyde is O-acylated with a long-chain acyl chloride allowed for the rapid ...
Petibois Cyril - - 2003
Recent studies have shown that endurance overtraining could result from successive and cumulative alterations in metabolism, which become chronic during training. The onset of this process is a biochemical alteration in carbohydrate (saccharide) metabolism. During endurance exercises, the amount of saccharide chains from two blood glycoproteins (alpha(2)-macroglobulin and alpha(1)-acid glycoprotein) ...
Sanceda N G - - 2003
The source of the formation of branched chain volatile fatty acids (VFA) in fish sauce was investigated. Certain branched VFA were derived from the degradation of specific amino acids as iso-butyric acid from valine and iso-valeric acid from leucine. Short and long straight chain VFA were significantly higher in the ...
Johnson David W - - 2003
Acetyl trimethylaminoethyl ester iodide derivatives have been used to selectively analyze isomeric long-chain hydroxy fatty acids by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The binary derivatives of 2-, 3-, 12- and 16-hydroxypalmitic acids afford remarkably different product ion spectra. Further discrimination between isomers is possible by acylating with pivaloyl chloride. ...
Rodriguez Maria - - 2003
Most preterm infant formulas contain medium-chain triacylglycerols (MCT), but the effects of MCT on polyunsaturated fatty acid status and metabolism are controversial. Thus, we studied the effects of MCT on linoleic acid metabolism using stable isotopes. Enterally fed preterm infants were randomized to receive for 7 days 40% of fat ...
Kunst L - - 2003
The cuticle covers the aerial portions of land plants. It consists of amorphous intracuticular wax embedded in cutin polymer, and epicuticular wax crystalloids that coat the outer plant surface and impart a whitish appearance. Cuticular wax is mainly composed of long-chain aliphatic compounds derived from very long chain fatty acids. ...
Sevastianov V I - - 2003
Samples of olyhydroxyalkanoates (PHAs), polyhydroxybutyrate (PHB) and copolymers poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) with 4 and 18 mol% hydroxyvalerate, synthesized by the bacteria Ralstonia eutropha B5786, were investigated. PHA films in contact with blood did not activate the hemostasis system at the level of cell response, but they did activate the coagulation system ...
Parton M - - 2003
Amyotrophic lateral sclerosis, also known as motor neuron disease, is a progressive neuromuscular disease that causes disability and eventual death. Various amino acid preparations, the three branched-chain amino acids (L-leucine, L-valine and L-isoleucine) or, alternatively, L-threonine have been used as experimental therapy. To examine the efficacy of amino acid therapies ...
Morr Michael - - 2002
The question which detailed structures of bacterial modulins determine their relative biological activity and respective host cell receptors was examined with synthetic variants of mycoplasmal lipopeptides as model compounds, as well as recombinant outer surface protein A (OspA) of Borrelia burgdorferi and lipoteichoic acid. Mouse fibroblasts bearing genetic deletions of ...
Martínez-Cuesta Carmen - - 2002
The effect of the bacteriocin lacticin 3147 on the branched-chain amino acid transamination by Lactococcus lactis IFPL359 was investigated. The bacteriocin provokes membrane permeabilisation of the cells, rendering them non-viable but metabolically active. Free diffusion of amino acids into the cell was facilitated. In addition, membrane permeabilisation promotes further cell ...
Dembitsky V M - - 2002
The hydrocarbon and lipid components of four strains of the filamentous cyanobacterium Scytonema sp. isolated from microbial community "Black Cover" of limestone walls in Jerusalem were identified by gas chromatography-mass spectrometry using serially coupled capillary columns. The dominant compounds were: 1-heptadecyne (1.5-8%), hexadecanoic acid (14-36%), (Z,Z)-9,12-octadecadienoic acid (12-30%), (Z,Z,Z)-9,12,15-octadecatrienoic acid ...
Carballeira Néstor M - - 2002
The phospholipid FA composition of the Caribbean sponge Agelas dispar was revisited and 40 different FA were identified. Among these a novel 2-methoxylated FA, namely, the anteiso methyl-branched 2-methoxy-14-methylhexadecanoic acid, was identified together with the recently discovered iso methyl-branched 2-methoxy-14-methylpentadecanoic acid and the normal-chain 2-methoxytetradecanoic acid. The structures of the ...
Nelson Dennis R - - 2002
The adult beetles Aphthona lacertosa and Aphthona nigriscutis, used as biocontrol agents for leafy spurge, had a complex mixture of hydrocarbons on their cuticular surface consisting of alkanes, methylalkanes, alkenes and alkadienes as determined by gas chromatography-mass spectrometry. A trace amount of wax esters were present. In both species, the ...
Asselineau Cécile - - 2002
Experimental observations, accumulated during several decades, have allowed an overall scheme for the biosynthesis of the mycolic acids, which are very long chain fatty acids of Mycobacteria to be proposed. But, in almost every step, several hypotheses are compatible with the experimental results, leading to variations of the overall scheme. ...
Bornet F R J - - 2002
Short-chain fructooligosaccharides occur in a number of edible plants, such as chicory, onions, asparagus, wheat... They are a group of linear fructose oligomers with a degree of polymerisation ranging from n = 1 up to 5 (oligosaccharides). Short-chain fructooligosaccharides, to a large extent, escape digestion in the human upper intestine ...
Lebeau Annette - - 2002
Crystal-storing histiocytosis (CSH) is a rare event in disorders associated with monoclonal gammopathy. The intracellular crystal formation is almost always accompanied by the expression of kappa light chains. However, the exact mechanism for the storage has not been clarified until now. We report a case of generalized CSH in a ...
Milo L A - - 2002
We examined the effect of short-chain fatty acid-supplemented total parenteral nutrition on proinflammatory cytokine levels in piglets. Piglets (N = 22) received either standard total parenteral nutrition or total parenteral nutrition supplemented with short-chain fatty acids. After seven days of continuous nutrient infusion, proinflammatory cytokine (TNF-alpha, IL-1beta, IL-6) abundance in ...
Petkova-Andonova Mariana - - 2002
In higher plants, long-chain fatty acid hydroperoxides are intermediates in the synthesis of a diverse group of bioactive compounds. We used the reverse trascriptase-polymerase chain reaction to isolate a gene responsible for the oxidization of fatty acids from Petunia hybrida. A P450 cDNA not isolated earlier, CYP92B1, contained an open ...
Atshaves Barbara P - - 2002
High levels of saturated, branched-chain fatty acids are deleterious to cells and animals, resulting in lipid accumulation and cytotoxicity. Although fatty acid binding proteins (FABPs) are thought to be protective, this hypothesis has not previously been examined. Phytanic acid (branched chain, 16-carbon backbone) induced lipid accumulation in L cell fibroblasts ...
Schroeder E K - - 2002
Tuberculosis resurged in the late 1980s and now kills more than 2 million people a year. The reemergence of tuberculosis as a potential public health threat, the high susceptibility of human immunodeficiency virus-infected persons to the disease, and the proliferation of multi-drug-resistant (MDR) strains have created much scientific interest in ...
Wolff Robert L - - 2002
In the present study, we investigated the alkenyl chains from sheep heart plasmalogens (1-O-alk-1'-enyl-2-acyl glycerophospholipids) after their conversion into trimethylene dioxyalkanyl (TMDOA) derivatives. Particular attention was given to monounsaturated alkenyl chains (C18 mainly). For this purpose, a combination of silver ion TLC and GLC on highly polar, very long capillary ...
Tagawa Yumi - - 2002
Gangliosides function in both physiological and pathological molecular recognition. Although much research has focused on the role of ganglioside glycans in recognition, fewer studies have addressed the role of the ceramide moiety. Ceramides of major brain gangliosides are composed predominantly of monounsaturated 18-carbon and 20-carbon long chain bases with a ...
Petroni A - - 2002
X-Adrenoleukodystrophy (X-ALD) is an inherited pathology characterized by very long-chain fatty acid accumulation in plasma as well as in different tissues. The nervous system, the adrenal cortex and the testis are primarily affected. Steroid metabolism which occurs in the adrenal cortex and in the testis might be severely impaired. We ...
Liakopoulou Effie - - 2002
Short-chain fatty acids (C2-C9) induce fetal hemoglobin synthesis in primary cell cultures, primates, and patients. We carried out experiments to test whether relationships exist between chemical structure and the Hb F-inducing potential of several short-chain fatty acid derivatives. BFUe cultures were performed in the presence of propionic and butyric congeners, ...
Roe Charles R - - 2002
The current dietary treatment of long-chain fatty acid oxidation defects (high carbohydrate with medium-even-chain triglycerides and reduced amounts of long-chain fats) fails, in many cases, to prevent cardiomyopathy, rhabdomyolysis, and muscle weakness. We hypothesized that the apparent defect in energy production results from a depletion of the catalytic intermediates of ...
Song Siqing - - 2002
A plasma desorption mass spectrometry study was made on the properties of glucose and glucose/glucuronic acid thin films as matrices for amino acids, small and large peptides and insulin. Amino acids and small peptides are distributed throughout the film as it is formed from aqueous solutions and the mass spectra ...
Mahmud Taifo - - 2002
Short chain carboxylic acids are well known as the precursors of fatty acid and polyketide biosynthesis. Iso-fatty acids, which are important for the control of membrane fluidity, are formed from branched chain starter units (isovaleryl-CoA and isobutyryl-CoA), which in turn are derived from the degradation of leucine and valine, respectively. ...
Schütt Burkhardt Siegfried - - 2002
With the aim of elucidating the mechanisms involved in the biosynthesis of medium-chain fatty acids in Cuphea lanceolata Ait., a crop accumulating up to 90% decanoic acid in seed triacylglycerols, cDNA clones of a beta-ketoacyl-acyl carrier protein (ACP) synthase IV (clKAS IV, EC 2.3.1.41) were isolated from C. lanceolata seed ...
Nichols David S - - 2002
The fatty acid composition of Listeria monocytogenes Scott A was determined by close-interval sampling over the entire biokinetic temperature range. There was a high degree of variation in the percentage of branched-chain fatty acids at any given temperature. The percentage of branched C17 components increased with growth temperature in a ...
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