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Mailloux Ryan J - - 2011
Aluminum (Al) is a metal toxin that has been implicated in the etiology of a number of diseases including Alzheimer's, Parkinson's, dialysis encephalopathy, and osteomalacia. Al has been shown to exert its effects by disrupting lipid membrane fluidity, perturbing iron (Fe), magnesium, and calcium homeostasis, and causing oxidative stress. However, ...
Yan Yizhe - - 2011
A novel metal-free intramolecular oxidative decarboxylative coupling of primary α-amino acids with 2-aminobenzoketones under mild and neutral conditions was developed. Different quinazolines can be selectively obtained by various oxidants.
Purwaha Preeti - - 2011
Docosapentaenoic acid (DPA) is a unique fatty acid that exists in two isomeric forms (n-3 and n-6), which differ in their physiological behaviors. DPA can undergo free radical-mediated peroxidation via lipoxygenase (LOX). 15-LOX, one of the LOX isomers, has received much attention in cancer research because of its very different ...
Wang Yuan - - 2011
Heterogeneous photocatalytic decomposition of perfluoroocatanoic acid (PFOA) by TiO(2) under 254nm UV light was investigated. Adding oxalic acid as a hole-scavenger significantly accelerated PFOA decomposition under nitrogen atmosphere. Fluoride ion, formic acid and six shorter-chain perfluorinated carboxylic acids (PFCAs) bearing C(2)-C(7) were identified as intermediates. When using perchloric acid (HClO(4)) ...
Ding Ye - - 2011
A novel and facile DDQ-mediated dehydrogenation from natural rigid polycyclic acids or flexible alkyl acids to generate lactones is described. The formation of lactones proceeds by a radical ion mechanism, which has been established by DPPH˙-mediated chemical identification, ESR spectroscopy and an enol intermediate trapping.
Luan He-Mi - - 2011
Aqueous (ET1) and alcoholic (ET2) extracts from Mactra veneriformis were studied for their antioxidant potentials using various in vitro assays. The ET2 was fractioned into four parts according to the polarity of the extractive medium, viz. ET2-p (petroleum ether), ET2-e (ethyl acetate), ET2-n (n-butanol) and ET2-w (water). Among the four fractions, ...
Andreo Ursula - - 2011
VLDL is produced by the liver. Its major protein is apoB100. Docosahexaenoic acid (DHA), a dietary polyunsaturated fatty acid (PUFA), reduces VLDL levels and is used therapeutically for hypertriglyceridemia. In model systems, DHA lowers VLDL secretion by inducing presecretory apoB100 degradation, a process dependent on PUFA-derived lipid peroxides. We hypothesized ...
Huang Ke-Jing - - 2011
Graphene/p-aminobenzoic acid composite film modified glassy carbon electrode (Gr/p-ABA/GCE) was first employed for the sensitive determination of dopamine (DA). The electrochemical behavior of DA at the modified electrode was investigated by cyclic voltametry (CV), differential pulse voltametry (DPV) and amperometric curve. The oxidation peak currents of DA increased dramatically at ...
Gauthier Kathryn M - - 2011
Cytochrome P-450 metabolites of arachidonic acid, the epoxyeicosatrienoic acids (EETs) and hydrogen peroxide (H(2)O(2)), are important signaling molecules in the kidney. In renal arteries, EETs cause vasodilation whereas H(2)O(2) causes vasoconstriction. To determine the physiological contribution of H(2)O(2), catalase is used to inactivate H(2)O(2). However, the consequence of catalase action ...
Liu Chaomin - - 2011
The range and scope of the oxidative oxazoline-oxazinone rearrangement-hydrogenation sequence (OOOH)-a short, direct asymmetric synthesis of α-amino acids from carboxylic acids-was explored. The highest yet reported diastereoselectivity for hydrogenation of the oxazinone CN bond (d.r.=>80:1) is disclosed and rationalized with the aid of ab initio molecular calculations.
Xu Qin - - 2011
Electrode with optical shapes is appreciated in microfluidics. In this article, we reported a flexible poly(dimethylsiloxane) (PDMS)-based gold electrode for ascorbic acid detection. Gold nanoparticles were chemically deposited on PDMS and the composite film was applied as working electrode. The electrode could undergo deformation and display good response performance without ...
Holla Vijaykumar R - - 2011
Although cancer cells have traditionally been thought to rely on the glycolytic pathway to generate ATP, recent studies suggest that cancer cells can shift to the fatty acid oxidation pathway as an alternative energy source. All of the factors that induce and regulate this adaptive shift in metabolism are not ...
Mikami Yoshinori - - 2011
Hydrogen sulfide (H2S) has recently been recognized as a signaling molecule as well as a cytoprotectant. We recently demonstrated that 3-mercaptopyruvate sulfurtransferase (3MST) produces H2S from 3-mercaptopyruvate (3MP).  Although a reducing substance is required for an intermediate persulfide at the active site of 3MST to release H2S, it has not ...
Ahmad Iqbal - - 2011
The kinetics of photolysis of ascorbic acid in cream formulations on UV irradiation has been studied using a specific spectrophotometric method with a reproducibility of ± 5%. The apparent first-order rate constants (k(obs)) for the photolysis of ascorbic acid in creams have been determined. The photoproducts formed in the cream ...
Zhang Xiaoyu - - 2011
NAD(P)H: quinone oxidoreductase1 (NQO1) is an important detoxification enzyme that can protect mammalian cells against toxic quinones and reduce the risk of tumorigenesis. In the present study, it was found that salvianolic acid B (SaB), lithospermic acid (LA) and rosmarinic acid (RA), three main hydrophilic constituents in Danshen, conjugated with ...
Mattijssen Frits - - 2011
Lipotoxicity describes the process of cellular dysfunction in response to lipid overload. In this issue of Cell Metabolism, Michel and colleagues (2011) provide evidence for a role of snoRNAs in palmitate-induced oxidative stress.
Mari Kannan M - - 2011
The anti lipid peroxidative and antioxidant effects of ellagic acid against isoproterenol-induced myocardial infarcted rats were reported previously. This study was designed to evaluate the protective effects of ellagic acid on the levels of cardiac troponin-T, lysosomal enzymes, and membrane bound ATPases along with the role of pro inflammatory cytokine. ...
Degirolamo Chiara C Laboratory of Lipid Metabolism and Cancer, Department of Translational Pharmacology, Consorzio Mario Negri Sud, Via Nazionale 8/A, 66030 Santa Maria Imbaro (Chieti), - - 2011
Colorectal cancer is the third most common malignancy worldwide and is often linked to obesity, a sedentary lifestyle, carbohydrate- and fat-rich diets and elevated fecal excretion of secondary bile acids. Accumulation of toxic bile acids triggers oxidative damage, mitochondrial dysfunction and tumor progression. Nuclear receptors are transcription factors crucially involved ...
Bradshaw Marc P - - 2011
Extensive reviews of research are available on the use of ascorbic acid, and its consequent degradation pathways, in physiological conditions or food matrices. However, very little information can be found for wine-related systems. This review highlights the relevant chemistry and reactivity of ascorbic acid with a focus on its behavior ...
Gorąca Anna - - 2011
α-Lipoic acid (LA; 5-(1,2-dithiolan-3-yl)pentanoic acid) was originally isolated from bovine liver by Reed et al. in 1951. LA was once considered a vitamin. Subsequently, it was found that LA is not a vitamin and is synthesized by plants and animals. LA is covalently bound to the ε-amino group of lysine ...
Abazi Sokol - - 2011
Radical alkylation of 2-(tert-butyl)-2-methyldioxolan-4-one, a chiral equivalent of glycolic acid, occurs with good to high diastereoselectivity that compares favorably with the corresponding enolate alkylation. The importance of the position of the transition state position, early or late, is highlighted.
Pandey A - - 2011
Coriandrum sativum (Linn.), a glabrous, aromatic, herbaceous annual plant, is well known for its use in jaundice. Essential oil, flavonoids, fatty acids, and sterols have been isolated from different parts of C. sativum. The plant has a very effective antioxidant profile showing 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, lipoxygenase inhibition, phospholipid ...
Yang Dongxu - - 2011
A copper/DIPEA-catalyzed, aldehyde-induced intermolecular decarboxylative coupling reaction of natural alpha-amino acids and phosphites or secondary phosphine oxides was developed. In this process, a series of potentially useful ligands for organic syntheses and biologically important unnatural amino acid derivatives (tertiary amino phosphorus compounds) were obtained.
Mortimer Monika - - 2011
In the current study, the toxicity mechanism of nanosized CuO (nCuO) to the freshwater ciliated protozoa <i>Tetrahymena thermophila</i> was studied. Changes in fatty acid profile, lipid peroxidation metabolites and reactive oxygen species (ROS) were measured. Bulk CuO and CuSO<sub>4</sub> served as controls for size and solubility and 3,5-dichorophenol (3,5-DCP) as ...
Tian Hong-Lei - - 2011
Ansu apricots growing wild in north Xinjiang are recognised as being one of the major wild-plant resources in China. In order to improve the level of comprehensive utilisation and the number of cultivated apricot varieties, the chemical composition of ansu apricot oil was analysed by capillary GC-MS and elucidated based ...
Fu Guoxing - - 2011
D-Arginine dehydrogenase (DADH) catalyzes the flavin-dependent oxidative deamination of D-arginine and other D-amino acids to the corresponding imino acids. The 1.07 Å atomic resolution structure of DADH crystallized with D-leucine unexpectedly revealed a covalent flavin N(5) adduct, instead of the expected iminoleucine product in the active site. This acyl adduct ...
Masi Laureane Nunes - - 2011
The effects of stearic (saturated) or oleic (monounsaturated) acids and their combination with ω-3 and ω-6 polyunsaturated fatty acids (PUFA) on death of endothelial cells (ECV-304 cell line) were investigated. We examined: loss of plasma membrane integrity, DNA fragmentation, accumulation of neutral lipids (NL) and release of reactive oxygen species ...
Yang Jin - - 2011
The composition and in vitro antioxidant activities of the essential oil and methanol extract of the aerial parts of Viola tianshanica were evaluated in this research. GC-MS analysis of the essential oil resulted in the identification of 15 constituents, representing 89.67% of the oil. The major compounds detected in the essential ...
Huang Li-Nan - - 2011
Analysis of spatial and temporal variations in the microbial community in the abandoned tailings impoundment of a Pb-Zn mine revealed distinct microbial populations associated with the different oxidation stages of the tailings. Although Acidithiobacillus ferrooxidans and Leptospirillum spp. were consistently present in the acidic tailings, acidophilic archaea, mostly Ferroplasma acidiphilum, ...
Sun Xiao-lin - - 2011
Over-expression of chloroplast glycerol-3-phosphate acyltransferase gene (LeGPAT) in tomato increased cis-unsaturated fatty acid content in phosphatidylglycerol (PG) of the thylakoid membrane. Under chilling stress, the oxygen evolving activity, the maximal photochemical efficiency of PSII (F (v)/F (m)), and superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities decreased less in sense ...
Bouo F-X D B - - 2011
The purpose of this paper is to study the redistribution of chemical species (OH, HO(2), H(2)O(2), HNO(3) and H(2)SO(4)) over West Africa, where the cloud cover is ubiquitously present, and where deep convection often develops. In this area, because of these cloud systems, chemical species are redistributed by the ascending ...
Guichardant M - - 2011
Because of their high degree of unsaturation, polyunsaturated fatty acids (PUFA) in mammals, with mainly 18, 20 and 22 carbons, can easily be autooxidized, and converted into many oxidized derivatives and degradation products. This short review reports on some of those relevant to the evaluation of oxidative stress in situ. ...
Hildebrandt Tatjana M - - 2011
Hydrogen sulfide is enzymatically produced in mammalian tissues and functions as a gaseous transmitter. However, H(2)S is also highly toxic as it inhibits mitochondrial respiration at the level of cytochrome c oxidase, which additionally is involved in sulfide oxidation. The accumulation of toxic sulfide levels contributes to the pathology of ...
Liu Chunhua - - 2011
The design, synthesis and biological evaluation of novel Leonurine-cysteine analog conjugates 3,5-dimethoxy-4-(2-amino-3-prop-2-ynylsulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1a), 3,5-dimethoxy-4-(2-animo-3-allysulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1b) and 3,5-dimethoxy-4-(3-(2-chlorocarbonyl-ethyldisulfanyl)-propionyl)-benzoic acid 4-guanidino-butyl ester (2) were reported in this paper. We tested their effects on hypoxia-induced neonatal rat ventricular myocytes. Our data showed that all of them had ...
Ryu Chang Seon - - 2011
Although methionine dependency is a phenotypic characteristic of tumor cells, it remains to be determined whether changes in sulfur amino acid metabolism occur in cancer cells resistant to chemotherapeutic medications. We compared expression/activity of sulfur amino acid metabolizing enzymes and cellular levels of sulfur amino acids and their metabolites between ...
Wanders Ronald J A - - 2011
Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) is a branched-chain fatty acid which cannot be beta-oxidized due to the presence of the first methyl group at the 3-position. Instead, phytanic acid undergoes alpha-oxidation to produce pristanic acid (2,6,10,14-tetramethylpentadecanoic acid) plus CO(2). Pristanic acid is a 2-methyl branched-chain fatty acid which can undergo beta-oxidation ...
Suenari Kazuyoshi - - 2011
AIMS: Omega-3 polyunsaturated fatty acids can modulate cardiac electrophysiology and reduce the genesis of atrial fibrillation. This study investigates the potential mechanisms through which eicosapentaenoic acid (EPA) reduces pulmonary vein (PV) arrhythmogenesis. MAIN METHODS: Conventional microelectrodes were used to record the action potentials (APs), before and after the EPA (0.1μM ...
Beserra Angela Márcia S - - 2011
Abstract Ellagic acid (EA), a plant-derived polyphenol, exhibits antioxidant, anti-inflammatory and gastroprotective effects. Its gastroprotective mechanisms have not been fully elucidated nor has its effects on chronic ulcer previously described. Toward these ends, the anti-ulcer activities of EA were evaluated in acute (ethanol and indomethacin) and chronic (acetic acid) ulcer ...
Moore Amy - - 2011
The suitability of insulating highly crystalline diamond particles as support for Pd based electrocatalysts is explored for the first time by evaluating the electrochemical stripping of CO and oxidation of formic acid in acid solutions.
Yusuf Mohammad - - 2011
INTRODUCTION: This study was hypothesized that salicylic acid elevates the level of antioxidant system that will protect plants from the stress generated by nickel and/or salinity. MATERIALS AND METHODS: Seeds of Brassica juncea were sown in sand amended with NiCl(2) (100 mg kg(-1)) and/or 15-day-old seedlings supplied for 3 days with NaCl (150 mM) ...
Göçer Hülya - - 2011
Caffeic acid phenethyl ester (CAPE), a plant polyphenolic concentrated in honeybee propolis, has been found to be biologically active in a variety of pathways. The aim of this study was to determine the antioxidant activity of CAPE using different methods such as total antioxidant activity by the thiocyanate method, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic ...
Ajami Dariush - - 2011
ABSTRACT Hydrogen bonding is a key determinant of much macromolecular structure in nature but individu-al donor and acceptor pairs are rarely observed in solu-tion. Their weak interactions result in nanosecond life-times and rapid exchange of partners. Reversible en-capsulation isolates molecules in very small spaces for milliseconds to hours and allows ...
Pike Lisa S - - 2011
Normal differentiated cells rely primarily on mitochondrial oxidative phosphorylation to produce adenosine triphosphate (ATP) to maintain their viability and functions by using three major bioenergetic fuels: glucose, glutamine and fatty acids. Many cancer cells, however, rely on aerobic glycolysis for their growth and survival, and recent studies indicate that some ...
Mehrotra Anurag - - 2011
The present study was designed to evaluate the antinociceptive profile of caffeic acid in mice and rats. Caffeic acid (5-100mg/kg, p.o.), in a dose dependent manner inhibited acetic acid-induced writhing and late phase of formalin-induced pain in mice, with an ED(50) of 22.38 and 10.92mg/kg, respectively. However, caffeic acid was ...
Ozyurt Dilek - - 2011
A Ce(IV)-based reducing capacity (CERAC) assay was developed to measure the total antioxidant capacity (TAC) of foods, in which Ce(IV) would selectively oxidize antioxidant compounds but not citric acid and reducing sugars which are not classified as antioxidants. The method is based on the electron-transfer (ET) reaction between Ce(IV) ion ...
Fan Xiaoqing - - 2011
This paper describes the synthesis of CdTe quantum dots (QDs) together capped by glutathione and thioglycolic acid (GSH and TGA) in aqueous solution. The narrow photoluminescence (fwhm≤40nm) CdTe QDs, whose emission spans most of the visible spectrum from green through red, has a quantum yield (QY) of 68% at room ...
Kumar M - - 2011
FTIR and Raman spectra of nicotinic acid and its N-oxide have been recorded and analyzed. The stabilities, optimized molecular geometries, APT charges and vibrational characteristics for the two possible conformers of nicotinic acid and its N-oxide have been computed using DFT method. The E (trans) conformers of both the molecules ...
Thiel Kerstin - - 2011
The formation of CuCl nanoplatelets from the ionic liquid precursor (ILP) butylpyridinium tetrachlorocuprate [C(4)Py](2)[CuCl(4)] using ascorbic acid as a reducing agent was investigated. In particular, electron paramagnetic resonance (EPR) spectroscopy was used to evaluate the interaction between ascorbic acid and the Cu(ii) ion before reduction to Cu(i). EPR spectroscopy suggests ...
Pates George O - - 2011
The reactivity of 10 charged phenyl radicals toward several amino acids was examined in the gas phase in a dual-cell Fourier transform ion cyclotron resonance mass spectrometer. All radicals abstract a hydrogen atom from the amino acids, as expected. The most electrophilic radicals (with the greatest calculated vertical electron affinities ...
Seguineau Catherine - - 2011
In a previous study, dietary supplementation with arachidonic acid (ARA) to oysters Crassostrea gigas increased haemocyte numbers, phagocytosis, and production of reactive oxygen species level (ROS) by haemocytes (Delaporte et al., 2006). To assess if the observed stimulation of these cellular responses resulted from changes of ARA-related prostaglandin (PG) production, ...
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