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Results 201 - 250 of 1091
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Núñez Nomelí P - - 2006
The PPAR-gamma ligands, 15-deoxy-Delta(12,14)-prostaglandin J(2) and ciglitazone, and the PPAR-alpha ligand, WY-14643, were examined for their effects on proliferation and apoptosis of A375 melanoma, DU145 and PC3 prostate cancer, and MB-MDA-231 breast cancer. While 15-deoxy-Delta(12,14)-prostaglandin J(2) inhibited proliferation of A375 melanoma, ciglitazone was inactive against this and the other cell ...
Choi Man-Yeon - - 2005
Sex pheromones of many moth species have relatively simple structures consisting of a hydrocarbon chain with a functional group and one to several double bonds. These sex pheromones are derived from fatty acids through specific biosynthetic pathways. We investigated the incorporation of deuterium-labeled tetradecanoic, hexadecanoic, and octadecanoic acid precursors into ...
Tsitsigiannis Dimitrios I - - 2005
Oxylipins called psi factors have been shown to alter the ratio of asexual to sexual sporulation in the filamentous fungus Aspergillus nidulans. Analysis of the A. nidulans genome has led to the identification of three fatty acid oxygenases (PpoA, PpoB and PpoC) predicted to produce psi factors. Here, it is ...
Kroner Steven M - - 2005
In an effort to gain further insight into the oxidation of the phenyl radical, this contribution details the first of three experiments designed to establish the heat of formation of the 2-oxepinoxy radical. We report here the synthesis of the previously unknown 2(7H)-oxepinone (12a) and 2(3H)-oxepinone (12b). We have determined ...
Ishikawa Hiroya - - 2005
Sorption of ionizable compounds of pyridines and aromatic carboxylic acids into low-density polyethylene (LDPE) film was investigated as a function of pH ranging from 4 to 7. The sorptions for pyridines were increased with increasing pH. Within the range examined, pH 7 was observed to promote the highest degree of ...
Oms Olivier - - 2005
The acidity constants of the reduced and oxidized species of ferrocenylphosphonic acids FcPO3H2, FcCH2PO3H2 and fc(PO3H2)2 (Fc = (eta5-C5H5)Fe(eta5-C5H4), fc = (eta5-C5H4)Fe(eta5-C5H4)) in water have been evaluated by potentiometric, 31P NMR, and electrochemical methods. The oxidized forms are more acidic than the reduced ones. The interaction between the redox centre ...
Hsieh S L - - 2005
Desaturation of fatty acids is an important adaptation mechanism for fish to maintain membrane fluidity under thermal stress. To comprehend the temperature adaptation mechanism in fish, we investigated the difference in the changes of stearoyl-CoA desaturase expression and fatty acid composition between milkfish and grass carp under cold acclimation. We ...
Oliviero Laetitia - - 2005
The positions of nu8a and nu*(NH) bands in the spectrum of protonated 2,6-dimethylpyridine vary with the strength of Brønsted acidity: the higher the nu*(NH) wavenumber and the lower the nu8a wavenumber, the stronger the acidity. The results obtained with 2,6-dimethylpyridine adsorption correlate with those obtained by CO adsorption experiments on ...
Na-Ranong Sutthicha - - 2005
The Delta(6)-fatty acid desaturase is a key enzyme in the synthesis of an important fatty acid, gamma-linolenic acid. We have characterized, by heterologous expression in Saccharomyces cerevisiae, substrate specificity and preference of Delta(6)-desaturase of Mucor rouxii. Fatty acid supplementation was carried out based on the predicted enzyme topology, fatty acid ...
Mijts Benjamin N - - 2005
A carotenoid desaturase homolog from Staphylococcus aureus (CrtOx) was identified. When expressed in engineered E. coli cells synthesizing linear C(30) carotenoids, polar carotenoid products were generated, identified as aldehyde and carboxylic acid C(30) carotenoid derivatives. The major product in this engineered pathway is the fully desaturated C(30) dialdehyde carotenoid 4,4'-diapolycopen-4,4'-dial. ...
Rios María Yolanda - - 2005
The structure elucidation and (1)H and (13)C assignments of iresin (1) and three new drimenes, 3beta,14-dihydroxy-Delta(7, 8)-drimen-11,12-acetonide (2), 3beta,7beta,14-trihidroxy-Delta(8, 9)-drimen-11,12-olide (3) and 3beta,7alpha,14-trihydroxy-Delta(8, 9)-drimen-11,12-olide (4), isolated from the aerial parts of the medicinal plant Iresine diffusa Humb. & Bonpl. ex Willd. are reported.
Grootveld Martin - - 2005
The applications of high resolution (1)H NMR analysis as a diagnostic probe for human saliva are reviewed with special reference to diabetes mellitus, and a recently published report regarding the ability of this technique to detect advanced glycation endproducts (AGEs) in this biofluid [Biochem. Biophys. Res. Commun. 323 (2004) 377-381]. ...
Khripach Vladimir A - - 2005
A new synthesis of both epimeric forms of 26-cholestanoic acids and 26-alcohols containing a 3beta-hydroxy-Delta(5)- or a Delta(4)-3-keto-functionality in ring A is described starting from stigmasterol or (20S)-3beta-acetoxy-pregn-5-en-20-carboxylic acid. The obtained compounds are useful as standards for studies of cholic acids. Construction of the side chain was achieved by linkage ...
Wang Hong-Lei - - 2005
Two Helicoverpa species, H. armigera and H. assulta use (Z)-11-hexadecenal and (Z)-9-hexadecenal as their sex attractant pheromone components but in opposite ratios. Since both female and male interspecific hybrids produced by female H. assulta and male H. armigera have been obtained in our laboratory, we can make a comparative study ...
Yuexian Fan - - 2005
The molecular recognition interaction of alpha-CD to chiral amino acids was investigated by using spectrophotometry based on methyl orange as a molecular probe. The molecular recognition ability depended on the inclusion formation constants. The molecular recognition of alpha-CD to aromatic amino acids was the order: DL-tryptophan > L-tryptophan > L-phenylalanine ...
Sacks Gavin L - - 2005
15N/14N isotope ratios are widely used to study processes and systems involving amino acids. Nitrogen isotope fractionation in biological processes occurs primarily at sites of bond-breaking and formation; the finest discrimination for "isotopic fingerprinting" and studies of isotopic fluxes is thus obtained at the position-specific level. While there are numerous ...
Wichard Thomas - - 2005
Reactive alpha,beta,gamma,delta-unsaturated aldehydes and oxo-acids produced by marine diatoms upon cell damage interfere negatively with the reproduction success of their grazers. A simple, sensitive and specific method based on gas-chromatography coupled to mass spectrometry (EI or CI/EC) was developed for the quantification of these deleterious substances in laboratory diatom cultures ...
Rukkumani R - - 2005
Alcohol use is contributing to an unprecedented decline in life expectancy. It induces hyperlipidemia when taken at higher concentrations. Alcoholics usually after a heavy binge of alcohols take fried food items normally made up of polyunsaturated fatty acids (PUFAs). The combined ingestion of alcohol and PUFAs is considered to be ...
Przychodzeń Witold - - 2005
The 15N NMR spectra of three N-alkyl-delta-carbomethoxyvalerothiohydroxamic acids (2) and six synthesized N-isopropylbenzothiohydroxamic acids (3) were measured and compared with appropriate spectra of structurally similar hydroxylamines (1), benzohydroxamic acids (4), benzamides (5) and thiobenzamides (6). The analysis of the chemical shifts of the thiohydroxamic acids under investigation indicates that the ...
Amaral Patricia de Aguiar Pde - - 2005
PURPOSE: A series of delta-valerolactones has been synthesized in good yields, by reaction of ethyl acetoacetate with several aldehydes in presence of LDA. METHODS AND RESULTS: The in vivo analgesic activity of these compounds has been evaluated. The results indicate that the lactones synthesized showed an important antinociceptive effect at ...
Grimaldi Paul André - - 2005
Peroxisome proliferator-activated receptors (PPARs) are transcription factors involved in both developmental and metabolic functions. There are activated by fatty acids, fatty acid metabolites, and synthetic compounds marketed for their lipid-lowering and antidiabetic actions. It was clearly established that activation of PPAR alpha and PPAR gamma, by fibrates and thiazolidinediones, respectively, ...
Fattahi Alireza - - 2004
Bond energies, acidities, and electron affinities are related in a thermodynamic cycle, and by measuring two of these quantities one can derive the third. This procedure is most often used to determine bond dissociation energies. In this work, we show that Delta H(o)(acid)(HX), EA(X(*)), and BDE(HX) are all linearly related ...
Chia Sin-Eng - - 2004
We carried out a cross-sectional study on a group of male workers to determine the frequency of delta-aminolevulinic acid dehydratase (ALAD) polymorphisms among Chinese, Malays and Indians workers who were exposed to low to medium levels of inorganic lead. Also, the association between ALAD1 and ALAD2 genotypes and neurobehavioral functions ...
Rodríguez Sergio - - 2004
Desaturation of fatty acids is a key reaction in the biosynthesis of moth sex pheromones. The main component of Spodoptera littoralis sex pheromone blend is produced by the action of Delta11 and Delta9 desaturases. In this article, we report on the cloning of four desaturase-like genes in this species: one ...
Bol Roland - - 2004
The long-term 'biodegradation' on soil amino acids was examined in the control plots of '42 parcelles' experiment, established in 1928 at INRA, Versailles (France). None of the plots is cultivated, but is kept free of weeds, and mixed to a depth of 25 cm twice yearly. Topsoil (0-10 cm depth) ...
Chen Xudong - - 2004
Electron transfer to perfluoro-1,3-dimethylcyclohexane in moist THF has yielded two quite different products. Tetrabutylammonium iodide irradiated with ultraviolet light gives a tetrabutylammonium enolate, but potassium fluorenone ketyl affords a cyclohexenyl anion. This allylic anion was isolated as its conjugate acid, a rather strong carbon acid. Ring inversion in the anion, ...
Oldiges M - - 2004
Using a concerted approach of biochemical standard preparation, analytical access via LC-MS/MS, glucose pulse, metabolic profiling, and statistical data analysis, the metabolism dynamics in the aromatic amino acid pathway has been stimulated, monitored, and analyzed in different tyrosine-auxotrophic L-phenylalanine-producing Escherichia coli strains. During the observation window from -4 s (before) ...
Wang Xuejun - - 2004
SUMMARY The preformed (Z,Z)-1-acetoxy-2-hydroxy-4-oxo-heneicosa-12,15-diene (AFD) is the most active antifungal compound in avocado; it affects the quiescence of Colletotrichum gloeosporioides in unripe fruit. One of the genes encoding Delta(12) fatty acid desaturase (avfad12) was hypothesized to take part in the biosynthesis of AFD, and its expression pattern and enzymatic activity ...
Abad José-Luis - - 2004
Thaumetopoea pityocampa pheromone glands contain desaturases that, after several sequential reactions from palmitic acid, catalyze the formation of a unique enyne fatty acid, which is the immediate sex pheromone precursor. In this article, we describe the synthesis of different stereospecifically deuterium-labeled and isotopically tagged palmitic acid probes needed to decipher ...
Karnik Deepali - - 2004
Progressive hepatocellular dysfunction in a neonate, resulting in elevated serum alpha-fetoprotein together with raised blood levels of tyrosine and methionine, a generalized amino aciduria and the absence of urinary delta-aminolevulinic acid and succinylacetone, suggests a diagnosis of tyrosinemia type Ib. Classical tyrosinemia type I arises from a deficiency of fumarylacetoacetate ...
Santos Francielli W - - 2004
Acute effects of cadmium in mice testes were evaluated. Animals received a single dose of CdCl2 (2.5 mg/kg or 5 mg/kg, intraperitoneally) and a number of toxicological parameters in mice testes were examined such as delta-aminolevulinic acid dehydratase (delta-ALA-D) activity, lipid peroxidation, hemoglobin content and components of the antioxidant defenses ...
Lee Chia-Fen - - 2004
To demonstrate photodynamic antimicrobial chemotherapy (PACT) against planktonic and biofilm cultures of Pseudomonas aeruginosa, using photoporphyrin IX which could be endogenously synthesized by administrating delta-aminolaevulinic acid (delta-ALA), and a light emitted diode (LED) array to photoactivate the photosensitizer. P. aeruginosa suspended cells or biofilms, grown on a rotating disk reactor, ...
Hongsthong Apiradee - - 2004
In the cyanobacterium Spirulina platensis, the desaturation process is carried out by three desaturases: the Delta(9), Delta(12) and Delta(6) desaturases, encoded by desC, desA and desD, respectively. The Delta(6) desaturase is responsible for the catalysis of linoleic acid, yielding gamma-linolenic acid (18:3(Delta 9,12,6)), the end-product of the process. In this ...
Kameda Tsunenori - - 2004
Two different crystalline polymorphs of valinomycin, the triclinic and monoclinic forms, have been studied by high resolution, solid state (13)C CP-MAS NMR spectroscopy. Although the two polymorphs of the crystal are remarkably similar, there are distinct differences in the isotropic chemical shifts between the two spectra. For the triclinic form, ...
de Gyves Emilio Mendoza - - 2004
A robust Agrobacterium-mediated transformation procedure was developed for Rigel, a commercial cultivar of evening primrose, and used to deliver a cDNA encoding a Delta(6)-desaturase from borage under the control of a cauliflower mosaic virus (CaMV) 35S promoter. Analysis of the transformed plants demonstrated an altered profile of polyunsaturated fatty acids, ...
Posadaz Ariana - - 2004
The Rose Bengal-sensitized photooxidations of the dipeptides l-tryptophyl-l-phenylalanine (Trp-Phe), l-tryptophyl-l-tyrosine (Trp-Tyr) and l-tryptophyl-l-tryptophan (Trp-Trp) have been studied in pH 7 water solution using static photolysis and time-resolved methods. Kinetic results indicate that the tryptophan (Trp) moiety interacts with singlet molecular oxygen (O(2)((1)Delta(g))) both through chemical reaction and through physical quenching, ...
Ziolkowski Piotr - - 2004
5-aminolevulinic acid (5-ALA) is a precursor in synthesis of endogenous porphyrins used to sensitize tumor tissues in photodynamic therapy (PDT). It is administered topically into a tumor which after the certain time, required for porphyrins to accumulate, is irradiated with visible light from the proper source at established wavelength. Our ...
Sirikantaramas Supaart - - 2004
Delta(1)-tetrahydrocannabinolic acid (THCA) synthase is the enzyme that catalyzes oxidative cyclization of cannabigerolic acid into THCA, the precursor of Delta(1)-tetrahydrocannabinol. We cloned a novel cDNA (GenBank trade mark accession number AB057805) encoding THCA synthase by reverse transcription and polymerase chain reactions from rapidly expanding leaves of Cannabis sativa. This gene ...
Theppeang Keson - - 2004
A cross-sectional analysis was performed to evaluate associations of polymorphisms in the vitamin D receptor (VDR), delta-aminolevulinic acid dehydratase (ALAD), and endothelial nitric oxide synthase (eNOS) genes with patella lead concentrations in 652 lead workers in the Republic of Korea. There was a wide range of patella lead (from below ...
Garbe Leif-A - - 2004
The biosyntheses of aroma active gamma- and delta-lactones have been previously characterized in yeasts and plants by incubation of labeled fatty acid derivatives. The lactones were considered as end products. Liquid cultures of the lactone-producing yeast Sporobolomyces odorus were used to investigate catabolic pathways of the lactones by incubation of ...
Martins Hugo F P - - 2004
The relative gas-phase acidities were determined for eight flavonoids, applying the kinetic method, by means of electrospray-ion trap mass spectrometry. The experimental acidity order, myricetin > luteolin > quercetin > (+/-)-taxifolin > kaempferol > apigenin > (+)-catechin > (+/-)-naringenin shows good agreement with the order obtained by theoretical calculations at ...
Revelles Olga - - 2004
Pseudomonas putida KT2440 is a soil microorganism that attaches to seeds and efficiently colonizes the plant's rhizosphere. Lysine is one of the major compounds in root exudates, and P. putida KT2440 uses this amino acid as a source of carbon, nitrogen, and energy. Lysine is channeled to delta-aminovaleric acid and ...
Dreos Renata - - 2004
The reaction of a cis beta folded organocobalt derivative with a salen-type ligand, 1, isolated as racemic compound of Delta and Lambda enantiomers, with enantiomerically pure alpha-l amino acids is reported. The reaction between racemic 1 and l-tyrosine afforded a mixture of the two diastereoisomers Delta-2 and Lambda-2, which could ...
Fink Kathrin - - 2004
For the authenticity assessment of (E)-methyl cinnamate from different origins, combustion/pyrolysis-isotope ratio mass spectrometry (C/P-IRMS) was used by an elemental analyzer (EA) and on-line capillary gas chromatography coupling (HRGC-C/P-IRMS). For that reason, (E)-methyl cinnamate self-prepared from synthetic, natural, and semisynthetic educts was analyzed in comparison to the commercial synthetic and ...
Collaud Sabine - - 2004
Due to its capability to induce accumulation of protoporphyrin IX (PpIX) selectively in a multitude of different pathologies, 5-aminolevulinic acid (ALA) and its derivatives have attracted enormous attention in the field of photodynamic therapy (PDT) in the past two decades. The photochemical and photophysical properties of PpIX have been used ...
Loewe Robert S - - 2004
The ability to attach redox-active molecules to oxide surfaces in controlled architectures (distance, orientation, packing density) is essential for the design of a variety of molecular-based information storage devices. We describe the synthesis of a series of redox-active molecules wherein each molecule bears a benzylphosphonic acid tether. The redox-active molecules ...
Muthukumaran Kannan - - 2004
Synthetic molecules bearing phosphonic acid groups can be readily attached to oxide surfaces. As part of a program in molecular-based information storage, we have developed routes for the synthesis of diverse porphyrinic compounds bearing phenylphosphonic acid tethers. The routes enable (1) incorporation of masked phosphonic acid groups in precursors for ...
Watanabe Kyoko - - 2004
In an effort to elucidate the molecular mechanisms of fatty acid desaturation in yeast, a complete gene encoding Delta 12 fatty acid desaturase of Saccharomyces kluyveri was cloned. The open reading frame of this gene (named Sk-FAD2) consists of 1,251 bp, encoding 416 amino acids. The deduced Sk-FAD2 protein had ...
Tarver James E JE - - 2004
A noncoded amino acid of cyclomarin A (1) was synthesized in a racemic fashion. The method employs a six-membered ring template to control the relative stereochemistry and introduction of the functional groups. Ultimately, Pd-catalyzed fragmentation of the lactone provided gamma,delta-unsaturated and delta,epsilon-unsaturated alpha-amino acids. A Pd-catalyzed ring opening of a ...
Kajikawa Masataka - - 2004
The liverwort Marchantia polymorpha contains high proportions of arachidonic and eicosapentaenoic acids. In general, these C20 polyunsaturated fatty acids (PUFA) are synthesized from linoleic and alpha -linolenic acids, respectively, by a series of reactions catalyzed by Delta(6)-desaturase, an ELO-like enzyme involved in Delta(6) elongation and Delta(5)-desaturase. Here we report the ...
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