Oleic acid derived metabolites in mouse neuroblastoma N18TG2 cells.

PubMed

Merkler, David J; Chew, Geoffrey H; Gee, Andrew J; Merkler, Kathleen A; Sorondo, Jean-Paul O; Johnson, Mitchell E

2004-10-05

Oleamide is an endogenous sleep-inducing lipid that has been isolated from the cerebrospinal fluid of sleep-deprived mammals. Oleamide is the best-understood member of the primary fatty acid amide family. One key unanswered question regarding oleamide and all other primary acid amides is the pathway by which these molecules are produced. One proposed pathway involves oleoyl-CoA and N-oleoylglycine as intermediates: oleic acid --> oleoyl-CoA --> N-oleoylglycine --> oleamide. The first and third reactions are known reactions, catalyzed by acyl-CoA synthetase and peptidylglycine alpha-amidating monooxygenase (PAM). Oleoyl-CoA formation from oleic acid has been demonstrated in vitro and in vivo while, to date, N-oleoylglycine cleavage to oleamide has been established only in vitro. PAM catalyzes the final step in alpha-amidated peptide biosynthesis, and its proposed role in primary fatty acid amide biosynthesis has been controversial. Mouse neuroblastoma N(18)TG(2) cells are an excellent model system for the study of oleamide biosynthesis because these cells convert [(14)C]-oleic acid to [(14)C]-oleamide and express PAM in a regulated fashion. We report herein that growth of the N(18)TG(2) cells in the presence of [(14)C]-oleic acid under conditions known to stimulate PAM expression generates an increase in [(14)C]-oleamide or in the presence of a PAM inhibitor generates [(14)C]-N-oleoylglycine. This represents the first identification of N-oleoylglycine from a biological source. In addition, N(18)TG(2) cell growth in the presence of N-oleoylglycine yields oleamide. These results strongly indicate that N-oleoylglycine is an intermediate in oleamide biosynthesis and provide further evidence that PAM does have a role in primary fatty acid amide production in vivo.

Boiler scale prevention employing an organic chelant

DOEpatents

Wallace, Steven L.; Griffin, Jr., Freddie; Tvedt, Jr., Thorwald J.

1984-01-01

An improved method of treating boiler water which employs an oxygen scavenging compound and a compound to control pH together with a chelating agent, wherein the chelating agent is hydroxyethylethylenediaminetriacetic acid.

Crystal structures of three co-crystals of 1,2-bis-(pyridin-4-yl)ethane with 4-alk-oxy-benzoic acids: 4-eth-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), 4-n-propoxybenzoic acid-1,2-bis(pyridin-4-yl)ethane (2/1) and 4-n-but-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1).

PubMed

Tabuchi, Yohei; Gotoh, Kazuma; Ishida, Hiroyuki

2015-11-01

The crystal structures of three hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), namely, 2C9H10O3·C12H12N2, (I), 2C10H12O3·C12H12N2, (II), and 2C11H14O3·C12H12N2, (III), have been determined at 93, 290 and 93 K, respectively. In (I), the asymmetric unit consists of one 4-eth-oxy-benzoic acid mol-ecule and one half-mol-ecule of 1,2-bis-(pyridin-4-yl)ethane, which lies on an inversion centre. In (II) and (III), the asymmetric units each comprise two crystallographically independent 4-alk-oxy-benzoic acid mol-ecules and one 1,2-bis-(pyridin-4-yl)ethane mol-ecule. In each crystal, the two components are linked by O-H⋯N hydrogen bonds, forming a linear hydrogen-bonded 2:1unit of the acid and the base. Similar to the structure of 2:1 unit of (I), the units of (II) and (III) adopt nearly pseudo-inversion symmetry. The 2:1 units of (I), (II) and (III) are linked via C-H⋯O hydrogen bonds, forming tape structures.

Evaluate the role of organic acids in the protection of ligands from radiolytic degradation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Anneka; Mezyk, Stehpen; Peterman, Dean

In the Advanced TALSPEAK process, the bis(2-ethylhexyl)phosphoric acid (HDEHP) extractant used in the traditional TALSPEAK process is replaced by the extractant 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]). In addition, the aqueous phase complexant and buffer used in traditional TALSPEAK is replaced with the combination of N-(2-hydroxyethyl)ethylenediamine-N,N’,N’-triacetic acid (HEDTA) and citric acid. In order to evaluate the possible impacts of gamma radiolysis upon the efficacy of the Advanced TALSPEAK flowsheet, aqueous and organic phases corresponding to the extraction section of the proposed flowsheet were irradiated in the INL test loop under an ambient atmosphere. The results of these studies conducted at INL,more » led INL researchers to conclude that the scarcity of values of rate constants for the reaction of hydroxyl radical with the components of the Advanced TALSPEAK process chemistry was severely limiting the interpretation of the results of radiolysis studies performed at the INL. In this work, the rate of reaction of hydroxyl radical with citric acid at several pH values was measured using a competitive pulse radiolysis technique. This report describes those results and is written in completion of milestone M3FT-16IN030102028, the goal of which was to evaluate the role of organic acids in the protection of ligands from radiolytic degradation. The results reported here demonstrate the importance of obtaining hydroxyl radical reaction rate data for the conditions that closely resemble actual solution conditions expected to be used in an actual solvent extraction process. This report describes those results and is written in completion of milestone M3FT-16IN030102028, the goal of which was to evaluate the role of organic acids in the protection of ligands from radiolytic degradation.« less

Metabolic solutions to the biosynthesis of some diaminomonocarboxylic acids in nature: Formation in cyanobacteria of the neurotoxins 3-N-methyl-2,3-diaminopropanoic acid (BMAA) and 2,4-diaminobutanoic acid (2,4-DAB).

PubMed

Nunn, Peter B; Codd, Geoffrey A

2017-12-01

The non-encoded diaminomonocarboxylic acids, 3-N-methyl-2,3-diaminopropanoic acid (syn: α-amino-β-methylaminopropionic acid, MeDAP; β-N-methylaminoalanine, BMAA) and 2,4-diaminobutanoic acid (2,4-DAB), are distributed widely in cyanobacterial species in free and bound forms. Both amino acids are neurotoxic in whole animal and cell-based bioassays. The biosynthetic pathway to 2,4-DAB is well documented in bacteria and in one higher plant species, but has not been confirmed in cyanobacteria. The biosynthetic pathway to BMAA is unknown. This review considers possible metabolic routes, by analogy with reactions used in other species, by which these amino acids might be biosynthesised by cyanobacteria, which are a widespread potential environmental source of these neurotoxins. Where possible, the gene expression that might be implicated in these biosyntheses is discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of dicyandiamide and dolomite application on N2O emission from an acidic soil.

PubMed

Shaaban, Muhammad; Wu, Yupeng; Peng, Qi-an; Lin, Shan; Mo, Yongliang; Wu, Lei; Hu, Ronggui; Zhou, Wei

2016-04-01

Soil acidification is a major problem for sustainable agriculture since it limits productivity of several crops. Liming is usually adopted to ameliorate soil acidity that can trigger soil processes such as nitrification, denitrification, and loss of nitrogen (N) as nitrous oxide (N2O) emissions. The loss of N following liming of acidic soils can be controlled by nitrification inhibitors (such as dicyandiamide). However, effects of nitrification inhibitors following liming of acidic soils are not well understood so far. Here, we conducted a laboratory study using an acidic soil to examine the effects of dolomite and dicyandiamide (DCD) application on N2O emissions. Three levels of DCD (0, 10, and 20 mg kg(-1); DCD0, DCD10, and DCD20, respectively) were applied to the acidic soil under two levels of dolomite (0 and 1 g kg(-1)) which were further treated with two levels of N fertilizer (0 and 200 mg N kg(-1)). Results showed that N2O emissions were highest at low soil pH levels in fertilizer-treated soil without application of DCD and dolomite. Application of DCD and dolomite significantly (P ≤ 0.001) reduced N2O emissions through decreasing rates of NH4 (+)-N oxidation and increasing soil pH, respectively. Total N2O emissions were reduced by 44 and 13% in DCD20 and dolomite alone treatments, respectively, while DCD20 + dolomite reduced N2O emissions by 54% when compared with DCD0 treatment. The present study suggests that application of DCD and dolomite to acidic soils can mitigate N2O emissions.

Dietary (n-3) fatty acids reduce plasma F2-isoprostanes but not prostaglandin F2alpha in healthy humans.

PubMed

Nälsén, Cecilia; Vessby, Bengt; Berglund, Lars; Uusitupa, Matti; Hermansen, Kjeld; Riccardi, Gabrielle; Rivellese, Angela; Storlien, Len; Erkkilä, Arja; Ylä-Herttuala, Seppo; Tapsell, Linda; Basu, Samar

2006-05-01

(n-3) Fatty acids are unsaturated and are therefore easily subject to oxidization; however, they have several beneficial health effects, which include protection against cardiovascular diseases. The aim of this study was to investigate whether (n-3) fatty acids, with a controlled fat quality in the background diet, affect nonenzymatic and enzymatic lipid peroxidation and antioxidant status in humans. A total of 162 men and women in a multicenter study (The KANWU study) were randomly assigned to a diet containing a high proportion of saturated fatty acids or monounsaturated fatty acids (MUFA) for 3 mo. Within each diet group, there was a second random assignment to supplementation with fish-oil capsules [3.6 g (n-3) fatty acids/d] or placebo. Biomarkers of nonenzymatic and enzymatic lipid peroxidation in vivo were determined by measuring 8-iso-prostaglandin F(2alpha) (8-iso-PGF(2alpha)) and prostaglandin F(2alpha) (PGF(2alpha)) concentrations in plasma at baseline and after 3 mo. Antioxidant status was determined by measuring plasma antioxidant capacity with an enhanced chemiluminescence assay. The plasma 8-iso-PGF(2alpha) concentration was significantly decreased after 3 mo of supplementation with (n-3) fatty acids (P = 0.015), whereas the PGF(2alpha) concentration was not affected. The antioxidant status was not affected by supplementation of (n-3) fatty acids, but was improved by the background diet with a high proportion of MUFA. We conclude that supplementation with (n-3) fatty acids decreases nonenzymatic free radical-catalyzed isoprostane formation, but does not affect cyclooxygenase-mediated prostaglandin formation.

UV and fluorescence spectral changes induced by neodymium binding of N,N'-ethylenebis[2-(o-hydroxyphenolic)glycine] and N,N'-di(2-hydroxybenzyl)ethylenediamine-N,N' diacetic acid.

PubMed

Wang, Zhijun; Yang, Binsheng

2006-11-01

In 0.01 M 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (Hepes), pH 7.4 and room temperature, the binding of neodymium to N,N'-ethylenebis[2-(o-hydroxyphenolic)glycine] (EHPG), or N,N'-di(2-hydroxybenzyl)ethylenediamine-N,N' diacetic acid (HBED) had been studied from 210 to 330 nm by means of difference UV spectra. Two peaks at 240 and 292 nm appear in difference UV spectra after neodymium binding to EHPG or HBED. The 1:1 stable complex can be confirmed from spectral titration curves. The molar extinction coefficient of Nd-EHPG and Nd-HBED complexes are Deltaepsilon(Nd-EHPG)=(12.93+/-0.21) x 10(3)cm(-1)M(-1), Deltaepsilon(Nd-HBED)=(14.45+/-0.51) x 10(5)cm(-1)M(-1) at 240 nm, respectively. Using EDTA as a competitor, the conditional equilibrium constants of the complexes are logK(Nd-EHPG)=11.89+/-0.09 and logK(Nd-HBED)=12.19+/-0.15, respectively. At the same conditions, fluorescence measurements show that neodymium binding to EHPG leads to a quenching of the fluorescence of EHPG at near 310 nm. However, there is no obvious fluorescence change of HBED at 318 nm with the binding of neodymium to HBED.

Biotransformation of nitroso aromatic compounds and 2-oxo acids to N-hydroxy-N-arylacylamides by thiamine-dependent enzymes in rat liver.

PubMed

Yoshioka, T; Uematsu, T

1998-07-01

The formation of N-hydroxy-N-arylacylamides from nitroso aromatic compounds and 2-oxo acids was investigated using rat liver subcellular fractions. Activities were found in both mitochondria and cytosol, except for activities for phenylpyruvate and glyoxylate; the former did not produce N-hydroxy-N-phenylphenylacetamide and the latter nonenzymatically produced N-hydroxy-N-phenylformamide with nitrosobenzene (NOB). The cytosolic activity of N-hydroxy-N-phenylglycolamide formation was indicated to be due to transketolase, which utilized hydroxypyruvate as a glycolic aldehyde donor to NOB. With mitochondria, 2-oxo acids (including hydroxypyruvate) served as substrates for the biotransformation of NOB to the corresponding N-hydroxy-N-phenylacylamides. The substrate preference was 2-oxobutyrate > pyruvate > 2-oxoisovalerate > 2-oxoisocaproate > 2-oxovalerate > 2-oxo-3-methylvalerate, judging from Vmax/half-saturating concentration for mitochondria values. The half-saturating concentrations for NOB were nearly constant. The mitochondrial activity was due to pyruvate dehydrogenase complex and branched-chain 2-oxo acid dehydrogenase complex (BCDHC). By using partially purified BCDHC, pyruvate and 2-oxobutyrate were found to be common substrates for both of the enzymes, and 2-oxoisovalerate was shown to be the most effective substrate for BCDHC. Analysis by the Taft equation indicated that the polar effects, rather than the steric effects, of the alkyl groups of 2-oxo acids are important for BCDHC-catalyzed formation of N-hydroxy-N-phenylacylamides. A positive Hammett constant obtained for the formation of N-hydroxy-N-arylisobutyramides indicates that an electron-withdrawing substituent makes the nitroso compounds susceptible to BCDHC-catalyzed biotransformation.

Derivatization of amino acids with N,N-dimethyl-2,4-dinitro-5-fluorobenzylamine for liquid chromatography/electrospray ionization mass spectrometry.

PubMed

Liu, Zhongfa; Minkler, Paul E; Lin, De; Sayre, Lawrence M

2004-01-01

Derivatization, separation and identification of amino acids with a novel compound, N,N-dimethyl-2,4-dinitro-5-fluorobenzylamine (DMDNFB), using high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) was demonstrated. Compared to derivatization with 2,4-dinitrofluorobenzene (DNFB), DMDNFB-derivatized amino acids and dipeptides exhibit much larger ion current signals in the commonly used ESI positive mode, which was attributed to the introduction of the N,N-dimethylaminomethyl protonatable site. Copyright 2004 John Wiley & Sons, Ltd.

Effect of Soil pH Increase by Biochar on NO, N2O and N2 Production during Denitrification in Acid Soils

PubMed Central

Obia, Alfred; Cornelissen, Gerard; Mulder, Jan; Dörsch, Peter

2015-01-01

Biochar (BC) application to soil suppresses emission of nitrous- (N2O) and nitric oxide (NO), but the mechanisms are unclear. One of the most prominent features of BC is its alkalizing effect in soils, which may affect denitrification and its product stoichiometry directly or indirectly. We conducted laboratory experiments with anoxic slurries of acid Acrisols from Indonesia and Zambia and two contrasting BCs produced locally from rice husk and cacao shell. Dose-dependent responses of denitrification and gaseous products (NO, N2O and N2) were assessed by high-resolution gas kinetics and related to the alkalizing effect of the BCs. To delineate the pH effect from other BC effects, we removed part of the alkalinity by leaching the BCs with water and acid prior to incubation. Uncharred cacao shell and sodium hydroxide (NaOH) were also included in the study. The untreated BCs suppressed N2O and NO and increased N2 production during denitrification, irrespective of the effect on denitrification rate. The extent of N2O and NO suppression was dose-dependent and increased with the alkalizing effect of the two BC types, which was strongest for cacao shell BC. Acid leaching of BC, which decreased its alkalizing effect, reduced or eliminated the ability of BC to suppress N2O and NO net production. Just like untreated BCs, NaOH reduced net production of N2O and NO while increasing that of N2. This confirms the importance of altered soil pH for denitrification product stoichiometry. Addition of uncharred cacao shell stimulated denitrification strongly due to availability of labile carbon but only minor effects on the product stoichiometry of denitrification were found, in accordance with its modest effect on soil pH. Our study indicates that stimulation of denitrification was mainly due to increases in labile carbon whereas change in product stoichiometry was mainly due to a change in soil pH. PMID:26397367

Effect of Soil pH Increase by Biochar on NO, N2O and N2 Production during Denitrification in Acid Soils.

PubMed

Obia, Alfred; Cornelissen, Gerard; Mulder, Jan; Dörsch, Peter

2015-01-01

Biochar (BC) application to soil suppresses emission of nitrous- (N2O) and nitric oxide (NO), but the mechanisms are unclear. One of the most prominent features of BC is its alkalizing effect in soils, which may affect denitrification and its product stoichiometry directly or indirectly. We conducted laboratory experiments with anoxic slurries of acid Acrisols from Indonesia and Zambia and two contrasting BCs produced locally from rice husk and cacao shell. Dose-dependent responses of denitrification and gaseous products (NO, N2O and N2) were assessed by high-resolution gas kinetics and related to the alkalizing effect of the BCs. To delineate the pH effect from other BC effects, we removed part of the alkalinity by leaching the BCs with water and acid prior to incubation. Uncharred cacao shell and sodium hydroxide (NaOH) were also included in the study. The untreated BCs suppressed N2O and NO and increased N2 production during denitrification, irrespective of the effect on denitrification rate. The extent of N2O and NO suppression was dose-dependent and increased with the alkalizing effect of the two BC types, which was strongest for cacao shell BC. Acid leaching of BC, which decreased its alkalizing effect, reduced or eliminated the ability of BC to suppress N2O and NO net production. Just like untreated BCs, NaOH reduced net production of N2O and NO while increasing that of N2. This confirms the importance of altered soil pH for denitrification product stoichiometry. Addition of uncharred cacao shell stimulated denitrification strongly due to availability of labile carbon but only minor effects on the product stoichiometry of denitrification were found, in accordance with its modest effect on soil pH. Our study indicates that stimulation of denitrification was mainly due to increases in labile carbon whereas change in product stoichiometry was mainly due to a change in soil pH.

NKG2D and CD94 bind to multimeric alpha2,3-linked N-acetylneuraminic acid.

PubMed

Imaizumi, Yuzo; Higai, Koji; Suzuki, Chiho; Azuma, Yutaro; Matsumoto, Kojiro

2009-05-08

Killer lectin-like receptors on natural killer cells mediate cytotoxicity through glycans on target cells including the sialyl Lewis X antigen (sLeX). We investigated whether NK group 2D (NKG2D) and CD94 can bind to sialylated N-linked glycans, using recombinant glutathione S-transferase-fused extracellular lectin-like domains of NKG2D (rNKG2Dlec) and CD94 (rCD94lec). Both rNKG2Dlec and rCD94lec bound to plates coated with high-sLeX-expressing transferrin secreted by HepG2 cells (HepTF). The binding of rNKG2Dlec and rCD94lec to HepTF was markedly suppressed by treatment of HepTF with neuraminidase and in the presence of N-acetylneuraminic acid. Moreover, rNKG2Dlec and rCD94lec bound to alpha2,3-sialylated human alpha(1)-acid glycoprotein (AGP) but not to alpha2,6-sialylated AGP. Mutagenesis revealed that (152)Y of NKG2D and (144)F and (160)N of CD94 were critical for HepTF binding. This is the first report that NKG2D and CD94 bind to alpha2,3-sialylated but not to alpha2,6-sialylated multi-antennary N-glycans.

Biogeochemistry of fluoride in a plant-solution system

NASA Technical Reports Server (NTRS)

Mackowiak, C. L.; Grossl, P. R.; Bugbee, B. G.

2003-01-01

Fluoride (F-) pollutants can harm plants and the animals feeding on them. However, it is largely unknown how complexing and chelating agents affect F bioavailability. Two studies were conducted that measured F- bioavailability and uptake by rice (Oryza sativa L.). In the first study, rice was grown in solution culture (pH 5.0) with 0, 2, or 4 mM F- as KF to compare the interaction of F- with humic acid (HA) and with a conventional chelating agent, N-hydroxyethylenthylenediaminetriacetic acid (HEDTA). In the second study, F was supplied at 0, 0.5, 1.0, and 2.0 mM KF with an additional 2 mM F- treatment containing solution Ca at 2x (2 mM Ca) the level used in the first study, to test the effect added Ca had on F- availability and uptake. Total biomass was greatest with HEDTA and F- < 1 mM. Leaf and stem F concentrations increased exponentially as solution F- increased linearly, with nearly no F partitioning into the seed. Results suggest that F was taken up as HF0 while F- uptake was likely restricted. Additionally, F- competed with HA for Ca, thus preventing the formation of Ca-HA flocculents. The addition of soluble Ca resulted in the precipitation of CaF2 solids on the root surface, as determined by tissue analysis and energy dispersive X-ray spectroscopy.

Sonocatalytic degradation of humic acid by N-doped TiO2 nano-particle in aqueous solution.

PubMed

Kamani, Hossein; Nasseri, Simin; Khoobi, Mehdi; Nabizadeh Nodehi, Ramin; Mahvi, Amir Hossein

2016-01-01

Un-doped and N-doped TiO2 nano-particles with different nitrogen contents were successfully synthesized by a simple sol-gel method, and were characterized by X-ray diffraction, field emission scanning electron microscopy, Energy dispersive X-ray analysis and UV-visible diffuse reflectance spectra techniques. Then enhancement of sonocatalytic degradation of humic acid by un-doped and N-doped TiO2 nano-particles in aqueous environment was investigated. The effects of various parameters such as initial concentration of humic acid, N-doping, and the degradation kinetics were investigated. The results of characterization techniques affirmed that the synthesis of un-doped and N-doped TiO2 nano-particles was successful. Degradation of humic acid by using different nano-particles obeyed the first-order kinetic. Among various nano-particles, N-doped TiO2 with molar doping ratio of 6 % and band gap of 2.92 eV, exhibited the highest sonocatalytic degradation with an apparent-first-order rate constant of 1.56 × 10(-2) min(-1). The high degradation rate was associated with the lower band gap energy and well-formed anatase phase. The addition of nano-catalysts could enhance the degradation efficiency of humic acid as well as N-doped TiO2 with a molar ratio of 6 %N/Ti was found the best nano-catalyst among the investigated catalysts. The sonocatalytic degradation with nitrogen doped semiconductors could be a suitable oxidation process for removal of refractory pollutants such as humic acid from aqueous solution.

Preparation of 7-hydroxy-2-oxoindolin-3-ylacetic acid and its [13C2], [5-n-3H], and [5-n-3H]-7-O-glucosyl analogues for use in the study of indol-3-ylacetic acid catabolism

NASA Technical Reports Server (NTRS)

Lewer, P.; Bandurski, R. S. (Principal Investigator)

1987-01-01

An improved synthesis of 7-hydroxy-2-oxoindolin-3-ylacetic acid via the base-induced condensation reaction between oxalate esters and 7-benzyloxyindolin-2-one is described. 7-Benzyloxyindolin-2-one was prepared in four steps and 50% overall yield from 3-hydroxy-2-nitrotoluene. The yield of the title compound from 7-benzyloxyindolin-2-one was 56%. This route was used to prepare 7-hydroxy-2-oxoindolin-3-yl[13C2]acetic acid in 30% yield from [13C2]oxalic acid dihydrate. The method could not be extended to the preparation of the corresponding [14C2]-compound. However, an enzyme preparation from Zea mays roots catalysed the conversion of carrier-free [5-n-3H]indol-3-ylacetic acid with a specific activity of 16.7 Ci mmol-1 to a mixture of 7-hydroxy-2-oxo[5-n-3H]indolin-3-ylacetic acid and its [5-n-3H]-7-O-glucoside in ca. 3 and 40% radiochemical yield respectively. The glucoside was converted into the 7-hydroxy compound in 80% yield by means of beta-glucosidase.

N-Docosahexaenoyl Dopamine, an Endocannabinoid-like Conjugate of Dopamine and the n-3 Fatty Acid Docosahexaenoic Acid, Attenuates Lipopolysaccharide-Induced Activation of Microglia and Macrophages via COX-2.

PubMed

Wang, Ya; Plastina, Pierluigi; Vincken, Jean-Paul; Jansen, Renate; Balvers, Michiel; Ten Klooster, Jean Paul; Gruppen, Harry; Witkamp, Renger; Meijerink, Jocelijn

2017-03-15

Several studies indicate that the n-3 long-chain polyunsaturated fatty acid docosahexaenoic acid (DHA) contributes to an attenuated inflammatory status in the development of neurodegenerative disorders, such as Alzheimer's and Parkinson's disease. To explain these effects, different mechanisms are being proposed, including those involving endocannabinoids and related signaling molecules. Many of these compounds belong to the fatty acid amides, conjugates of fatty acids with biogenic amines. Conjugates of DHA with ethanolamine or serotonin have previously been shown to possess anti-inflammatory and potentially neuroprotective properties. Here, we synthesized another amine conjugate of DHA, N-docosahexaenoyl dopamine (DHDA), and tested its immune-modulatory properties in both RAW 264.7 macrophages and BV-2 microglial cells. N-Docosahexaenoyl dopamine significantly suppressed the production of nitric oxide (NO), the cytokine interleukin-6 (IL-6), and the chemokines macrophage-inflammatory protein-3α (CCL20) and monocyte chemoattractant protein-1 (MCP-1), whereas its parent compounds, dopamine and DHA, were ineffective. Further exploration of potential effects of DHDA on key inflammatory mediators revealed that cyclooxygenase-2 (COX-2) mRNA level and production of prostaglandin E 2 (PGE 2 ) were concentration-dependently inhibited in macrophages. In activated BV-2 cells, PGE 2 production was also reduced, without changes in COX-2 mRNA levels. In addition, DHDA did not affect NF-kB activity in a reporter cell line. Finally, the immune-modulatory activities of DHDA were compared with those of N-arachidonoyl dopamine (NADA) and similar potencies were found in both cell types. Taken together, our data suggest that DHDA, a potentially endogenous endocannabinoid, may be an additional member of the group of immune-modulating n-3 fatty acid-derived lipid mediators.

Primary fatty acid amide metabolism: conversion of fatty acids and an ethanolamine in N18TG2 and SCP cells.

PubMed

Farrell, Emma K; Chen, Yuden; Barazanji, Muna; Jeffries, Kristen A; Cameroamortegui, Felipe; Merkler, David J

2012-02-01

Primary fatty acid amides (PFAM) are important signaling molecules in the mammalian nervous system, binding to many drug receptors and demonstrating control over sleep, locomotion, angiogenesis, and many other processes. Oleamide is the best-studied of the primary fatty acid amides, whereas the other known PFAMs are significantly less studied. Herein, quantitative assays were used to examine the endogenous amounts of a panel of PFAMs, as well as the amounts produced after incubation of mouse neuroblastoma N(18)TG(2) and sheep choroid plexus (SCP) cells with the corresponding fatty acids or N-tridecanoylethanolamine. Although five endogenous primary amides were discovered in the N(18)TG(2) and SCP cells, a different pattern of relative amounts were found between the two cell lines. Higher amounts of primary amides were found in SCP cells, and the conversion of N-tridecanoylethanolamine to tridecanamide was observed in the two cell lines. The data reported here show that the N(18)TG(2) and SCP cells are excellent model systems for the study of PFAM metabolism. Furthermore, the data support a role for the N-acylethanolamines as precursors for the PFAMs and provide valuable new kinetic results useful in modeling the metabolic flux through the pathways for PFAM biosynthesis and degradation.

Synthesis and biological evaluation of N-difluoromethyl-1,2-dihydropyrid-2-one acetic acid regioisomers: dual inhibitors of cyclooxygenases and 5-lipoxygenase.

PubMed

Yu, Gang; Praveen Rao, P N; Chowdhury, Morshed A; Abdellatif, Khaled R A; Dong, Ying; Das, Dipankar; Velázquez, Carlos A; Suresh, Mavanur R; Knaus, Edward E

2010-04-01

A new group of acetic acid (7a-c, R(1) = H), and propionic acid (7d-f, R(1) = Me), regioisomers wherein a N-difluoromethyl-1,2-dihydropyrid-2-one moiety is attached via its C-3, C-4, and C-5 position was synthesized. This group of compounds exhibited a more potent inhibition, and hence selectivity, for the cyclooxygenase-2 (COX-2) relative to the COX-1 isozyme. Attachment of the N-difluoromethyl-1,2-dihydropyrid-2-one ring system to an acetic acid, or propionic acid, moiety confers potent 5-LOX inhibitory activity, that is, absent in traditional arylacetic acid NSAIDs. 2-(1-Difluoromethyl-2-oxo-1,2-dihydropyridin-5-yl)acetic acid (7c) exhibited the best combination of dual COX-2 and 5-LOX inhibitory activities. Molecular modeling (docking) studies showed that the highly electronegative CHF(2) substituent present in 7c, that showed a modest selectivity for the COX-2 isozyme, is oriented within the secondary pocket (Val523) present in COX-2 similar to the sulfonamide (SO(2)NH(2)) COX-2 pharmacophore present in celecoxib, and that the N-difluoromethyl-1,2-dihydropyrid-2-one pharmacophore is oriented close to the region containing the LOX enzyme catalytic iron (His361, His366, and His545). Accordingly, the N-difluoromethyl-1,2-dihyrdopyrid-2-one moiety possesses properties suitable for the design of dual COX-2/5-LOX inhibitory drugs. 2010 Elsevier Ltd. All rights reserved.

Investigation of on-line chelant addition to PWR steam generators. Annual report, 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tvedt, T.J.; Wallace, S.L.; Griffin, F. Jr.

1982-11-01

The thermostability of both ethylenediaminetetraacetic acid (EDTA) and hydroxyethylethylenediamininetriacetic acid (HEDTA) metal chelates in all volatile treatment water chemistry (AVT) was shown to be greater than or equal to thermostability of EDTA metal chelates in phosphate-sulfite water chemistry. HEDTA metal chelates were shown to have a much greater stability than EDTA metal chelates. Using samples taken from the EDTA metal chelate thermostability studies and samples from Commonwealth Research Corporation (CRC) model steam generators (MSG), EDTA decomposition products were determined. Active metal surfaces were shown to become passivated when exposed to EDTA and HEDTA concentrations as high as 0.1% w/w inmore » AVT. Trace amounts of iron in the water were found to increase the rate of passivation. Material balance and visual inspection data from CRC model steam generators showed that metal is being transported through and cleaning from the MSG's. EDTA metal chelates were removed from chelate solutions by passing the solutions over strong anion exchange resins.« less

Synthesis and characterization of a novel aminopolycarboxylate complexant for efficient trivalent f-element differentiation: N-butyl-2-acetamide-diethylenetriamine- N, N', N", N"-tetraacetic acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heathman, Colt R.; Grimes, Travis S.; Jansone-Popova, Santa

The novel metal ion complexant N-butyl-2-acetamide-diethylenetriamine-N,N',N",N"-tetraacetic acid (DTTA-BuA) uses an amide functionalization to increase the total ligand acidity and attain efficient 4f/5f differentiation in low pH conditions. The amide, when located on the diethylenetriamine platform containing four acetate pendant arms maintains the octadentate coordination sphere for all investigated trivalent f-elements. This compact coordination environment inhibits the protonation of LnL- complexes, as indicated by lower K 111 constants relative to the corresponding protonation site of the free ligand. For actinide ions, the enhanced stability of AnL- lowers the K 111 for americium and curium beyond the aptitude of potentiometric detection. Densitymore » functional theory computations indicate the difference in the back-donation ability of Am 3+ and Eu 3+ f-orbitals is mainly responsible for stronger proton affinity of EuL- compared to AmL-. The measured stability constants for the formation of AmL- and CmL- complexes are consistently higher, relative to ML- complexes with lanthanides of similar charge density. When compared with the conventional aminopolycarboxylate diethylenetriamine pentaacetic acid (DTPA), the modified DTTA-BuA complexant features higher ligand acidity and the important An 3+/Ln 3+ differentiation when deployed on a liquid–liquid distribution platform.« less

Supercritical SC-CO(2) and Soxhlet n-Hexane Extract of Tunisian Opuntia ficus indica Seeds and Fatty Acids Analysis.

PubMed

Yeddes, Nizar; Chérif, Jamila Kalthoum; Jrad, Amel; Barth, Danielle; Trabelsi-Ayadi, Malika

2012-01-01

The fatty acids profiles of Tunisian Opuntia ficus indica seeds (spiny and thornless form) were investigated. Results of supercritical carbon dioxide (SC-CO(2)) and soxhlet n-hexane extract were compared. Quantitatively, the better yield was obtained through soxhlet n-hexane: 10.32% (spiny) and 8.91% (thornless) against 3.4% (spiny) and 1.94% (thornless) by SC-CO(2) extract (T = 40°C, P = 180 bar, time = 135 mn, CO(2) flow rate = 15 mL·s(-1)). Qualitatively, the main fatty acids components were the same for the two types of extraction. Linoleic acid was the major compound, SC-CO(2): 57.60% (spiny), 59.98% (thornless), soxhlet n-hexane: 57.54% (spiny), 60.66% (thornless), followed by oleic acid, SC-CO(2): 22.31% (spiny), 22.40% (thornless), soxhlet n-hexane: 25.28% (spiny), 20.58% (thornless) and palmitic acid, SC-CO(2): 14.3% (spiny), 12.92% (thornless), soxhlet n-hexane: 11.33% (spiny), 13.08% (thornless). The SC-CO(2) profiles fatty acids showed a richness with other minority compounds such as C(20:1), C(20:2), and C(22).The seeds oil was highly unsaturated (US = 4.44-5.25), and the rising temperatures donot affect the selectivity of fatty acids extract by SC-CO2: US = 4.44 (T = 40°C) and 4.13 (T = 70°C).

Supercritical SC-CO2 and Soxhlet n-Hexane Extract of Tunisian Opuntia ficus indica Seeds and Fatty Acids Analysis

PubMed Central

Yeddes, Nizar; Chérif, Jamila Kalthoum; Jrad, Amel; Barth, Danielle; Trabelsi-Ayadi, Malika

2012-01-01

The fatty acids profiles of Tunisian Opuntia ficus indica seeds (spiny and thornless form) were investigated. Results of supercritical carbon dioxide (SC-CO2) and soxhlet n-hexane extract were compared. Quantitatively, the better yield was obtained through soxhlet n-hexane: 10.32% (spiny) and 8.91% (thornless) against 3.4% (spiny) and 1.94% (thornless) by SC-CO2 extract (T = 40°C, P = 180 bar, time = 135 mn, CO2 flow rate = 15 mL·s−1). Qualitatively, the main fatty acids components were the same for the two types of extraction. Linoleic acid was the major compound, SC-CO2: 57.60% (spiny), 59.98% (thornless), soxhlet n-hexane: 57.54% (spiny), 60.66% (thornless), followed by oleic acid, SC-CO2: 22.31% (spiny), 22.40% (thornless), soxhlet n-hexane: 25.28% (spiny), 20.58% (thornless) and palmitic acid, SC-CO2: 14.3% (spiny), 12.92% (thornless), soxhlet n-hexane: 11.33% (spiny), 13.08% (thornless). The SC-CO2 profiles fatty acids showed a richness with other minority compounds such as C20:1, C20:2, and C22.The seeds oil was highly unsaturated (US = 4.44–5.25), and the rising temperatures donot affect the selectivity of fatty acids extract by SC-CO2: US = 4.44 (T = 40°C) and 4.13 (T = 70°C). PMID:22754699

The suppression of the N-nitrosating reaction by chlorogenic acid.

PubMed Central

Kono, Y; Shibata, H; Kodama, Y; Sawa, Y

1995-01-01

N-Nitrosation of a model aromatic amine (2,3-diamino-naphthalene) by the N-nitrosating agent produced by nitrite in acidic solution was inhibited by a polyphenol, chlorogenic acid, which is an ester of caffeic acid quinic acid. Caffeic acid also inhibited the N-nitrosation, but quinic acid did not. 1,2-Benzenediols and 3,4-dihydroxybenzoic acid had inhibitory activities. Chlorogenic acid, caffeic acid, 1,2-benzenediols and 3,4-dihydroxybenzoic acid were able to scavenge the stable free radical, 1,1-diphenyl-2-picrylhydrazyl. Chlorogenic acid was found to be nitrated by acidic nitrite. The kinetic studies and the nitration observed only by bubbling of nitric oxide plus nitrogen dioxide gases indicated that the nitrating agent was nitrogen sesquioxide. The observations showed that the mechanism by which chlorogenic acid inhibited N-nitrosation of 2,3-diamino-naphthalene is due to its ability to scavenge the nitrosating agent, nitrogen sesquioxide. Chlorogenic acid may be effective not only in protecting against oxidative damage but also in inhibiting potentially mutagenic and carcinogenic reactions in vivo. PMID:8554543

The Prion Protein N1 and N2 Cleavage Fragments Bind to Phosphatidylserine and Phosphatidic Acid; Relevance to Stress-Protection Responses.

PubMed

Haigh, Cathryn L; Tumpach, Carolin; Drew, Simon C; Collins, Steven J

2015-01-01

Internal cleavage of the cellular prion protein generates two well characterised N-terminal fragments, N1 and N2. These fragments have been shown to bind to anionic phospholipids at low pH. We sought to investigate binding with other lipid moieties and queried how such interactions could be relevant to the cellular functions of these fragments. Both N1 and N2 bound phosphatidylserine (PS), as previously reported, and a further interaction with phosphatidic acid (PA) was also identified. The specificity of this interaction required the N-terminus, especially the proline motif within the basic amino acids at the N-terminus, together with the copper-binding region (unrelated to copper saturation). Previously, the fragments have been shown to be protective against cellular stresses. In the current study, serum deprivation was used to induce changes in the cellular lipid environment, including externalisation of plasma membrane PS and increased cellular levels of PA. When copper-saturated, N2 could reverse these changes, but N1 could not, suggesting that direct binding of N2 to cellular lipids may be part of the mechanism by which this peptide signals its protective response.

The Prion Protein N1 and N2 Cleavage Fragments Bind to Phosphatidylserine and Phosphatidic Acid; Relevance to Stress-Protection Responses

PubMed Central

Haigh, Cathryn L.; Tumpach, Carolin; Drew, Simon C.; Collins, Steven J.

2015-01-01

Internal cleavage of the cellular prion protein generates two well characterised N-terminal fragments, N1 and N2. These fragments have been shown to bind to anionic phospholipids at low pH. We sought to investigate binding with other lipid moieties and queried how such interactions could be relevant to the cellular functions of these fragments. Both N1 and N2 bound phosphatidylserine (PS), as previously reported, and a further interaction with phosphatidic acid (PA) was also identified. The specificity of this interaction required the N-terminus, especially the proline motif within the basic amino acids at the N-terminus, together with the copper-binding region (unrelated to copper saturation). Previously, the fragments have been shown to be protective against cellular stresses. In the current study, serum deprivation was used to induce changes in the cellular lipid environment, including externalisation of plasma membrane PS and increased cellular levels of PA. When copper-saturated, N2 could reverse these changes, but N1 could not, suggesting that direct binding of N2 to cellular lipids may be part of the mechanism by which this peptide signals its protective response. PMID:26252007

Effect of dolomite and biochar addition on N2O and CO2 emissions from acidic tea field soil

PubMed Central

Win, Khin Thuzar; Shibata, Akira; Yamamoto, Akinori; Sano, Tomohito; Hirono, Yuhei

2018-01-01

A laboratory study was conducted to study the effects of liming and different biochar amendments on N2O and CO2 emissions from acidic tea field soil. The first experiment was done with three different rates of N treatment; N 300 (300 kg N ha-1), N 600 (600 kg N ha-1) and N 900 (900 kg N ha-1) and four different rates of bamboo biochar amendment; 0%, 0.5%, 1% and 2% biochar. The second experiment was done with three different biochars at a rate of 2% (rice husk, sawdust, and bamboo) and a control and lime treatment (dolomite) and control at two moisture levels (50% and 90% water filled pore space (WFPS)). The results showed that dolomite and biochar amendment significantly increased soil pH. However, only biochar amendment showed a significant increase in total carbon (C), C/N (the ratio of total carbon and total nitrogen), and C/IN ratio (the ratio of total carbon and inorganic nitrogen) at the end of incubation. Reduction in soil NO3--N concentration was observed under different biochar amendments. Bamboo biochar with the rates of 0.5, 1 and 2% reduced cumulative N2O emission by 38%, 48% and 61%, respectively, compare to the control soil in experiment 1. Dolomite and biochar, either alone or combined significantly reduced cumulative N2O emission by 4.6% to 32.7% in experiment 2. Reduction in N2O production under biochar amendment was due to increases in soil pH and decreases in the magnitude of mineral-N in soil. Although, both dolomite and biochar increased cumulative CO2 emission, only biochar amendment had a significant effect. The present study suggests that application of dolomite and biochar to acidic tea field soil can mitigate N2O emissions. PMID:29394272

Effect of dolomite and biochar addition on N2O and CO2 emissions from acidic tea field soil.

PubMed

Oo, Aung Zaw; Sudo, Shigeto; Akiyama, Hiroko; Win, Khin Thuzar; Shibata, Akira; Yamamoto, Akinori; Sano, Tomohito; Hirono, Yuhei

2018-01-01

A laboratory study was conducted to study the effects of liming and different biochar amendments on N2O and CO2 emissions from acidic tea field soil. The first experiment was done with three different rates of N treatment; N 300 (300 kg N ha-1), N 600 (600 kg N ha-1) and N 900 (900 kg N ha-1) and four different rates of bamboo biochar amendment; 0%, 0.5%, 1% and 2% biochar. The second experiment was done with three different biochars at a rate of 2% (rice husk, sawdust, and bamboo) and a control and lime treatment (dolomite) and control at two moisture levels (50% and 90% water filled pore space (WFPS)). The results showed that dolomite and biochar amendment significantly increased soil pH. However, only biochar amendment showed a significant increase in total carbon (C), C/N (the ratio of total carbon and total nitrogen), and C/IN ratio (the ratio of total carbon and inorganic nitrogen) at the end of incubation. Reduction in soil NO3--N concentration was observed under different biochar amendments. Bamboo biochar with the rates of 0.5, 1 and 2% reduced cumulative N2O emission by 38%, 48% and 61%, respectively, compare to the control soil in experiment 1. Dolomite and biochar, either alone or combined significantly reduced cumulative N2O emission by 4.6% to 32.7% in experiment 2. Reduction in N2O production under biochar amendment was due to increases in soil pH and decreases in the magnitude of mineral-N in soil. Although, both dolomite and biochar increased cumulative CO2 emission, only biochar amendment had a significant effect. The present study suggests that application of dolomite and biochar to acidic tea field soil can mitigate N2O emissions.

Primary fatty acid amide metabolism: conversion of fatty acids and an ethanolamine in N18TG2 and SCP cells1[S

PubMed Central

Farrell, Emma K.; Chen, Yuden; Barazanji, Muna; Jeffries, Kristen A.; Cameroamortegui, Felipe; Merkler, David J.

2012-01-01

Primary fatty acid amides (PFAM) are important signaling molecules in the mammalian nervous system, binding to many drug receptors and demonstrating control over sleep, locomotion, angiogenesis, and many other processes. Oleamide is the best-studied of the primary fatty acid amides, whereas the other known PFAMs are significantly less studied. Herein, quantitative assays were used to examine the endogenous amounts of a panel of PFAMs, as well as the amounts produced after incubation of mouse neuroblastoma N18TG2 and sheep choroid plexus (SCP) cells with the corresponding fatty acids or N-tridecanoylethanolamine. Although five endogenous primary amides were discovered in the N18TG2 and SCP cells, a different pattern of relative amounts were found between the two cell lines. Higher amounts of primary amides were found in SCP cells, and the conversion of N-tridecanoylethanolamine to tridecanamide was observed in the two cell lines. The data reported here show that the N18TG2 and SCP cells are excellent model systems for the study of PFAM metabolism. Furthermore, the data support a role for the N-acylethanolamines as precursors for the PFAMs and provide valuable new kinetic results useful in modeling the metabolic flux through the pathways for PFAM biosynthesis and degradation. PMID:22095832

Cinnamic acid hydrogen bonds to isoniazid and N'-(propan-2-ylidene)isonicotinohydrazide, an in situ reaction product of isoniazid and acetone.

PubMed

Sarcevica, Inese; Orola, Liana; Veidis, Mikelis V; Belyakov, Sergey

2014-04-01

A new polymorph of the cinnamic acid-isoniazid cocrystal has been prepared by slow evaporation, namely cinnamic acid-pyridine-4-carbohydrazide (1/1), C9H8O2·C6H7N3O. The crystal structure is characterized by a hydrogen-bonded tetrameric arrangement of two molecules of isoniazid and two of cinnamic acid. Possible modification of the hydrogen bonding was investigated by changing the hydrazide group of isoniazid via an in situ reaction with acetone and cocrystallization with cinnamic acid. In the structure of cinnamic acid-N'-(propan-2-ylidene)isonicotinohydrazide (1/1), C9H8O2·C9H11N3O, carboxylic acid-pyridine O-H···N and hydrazide-hydrazide N-H···O hydrogen bonds are formed.

α-Amidoalkylating agents from N-acyl-α-amino acids: 1-(N-acylamino)alkyltriphenylphosphonium salts.

PubMed

Mazurkiewicz, Roman; Adamek, Jakub; Październiok-Holewa, Agnieszka; Zielińska, Katarzyna; Simka, Wojciech; Gajos, Anna; Szymura, Karol

2012-02-17

N-Acyl-α-amino acids were efficiently transformed in a two-step procedure into 1-N-(acylamino)alkyltriphenylphosphonium salts, new powerful α-amidoalkylating agents. The effect of the α-amino acid structure, the base used [MeONa or a silica gel-supported piperidine (SiO(2)-Pip)], and the main electrolysis parameters (current density, charge consumption) on the yield and selectivity of the electrochemical decarboxylative α-methoxylation of N-acyl-α-amino acids (Hofer-Moest reaction) was investigated. For most proteinogenic and all studied unproteinogenic α-amino acids, very good results were obtained using a substoichiometric amount of SiO(2)-Pip as the base. Only in the cases of N-acylated cysteine, methionine, and tryptophan, attempts to carry out the Hofer-Moest reaction in the applied conditions failed, probably because of the susceptibility of these α-amino acids to an electrochemical oxidation on the side chain. The methoxy group of N-(1-methoxyalkyl)amides was effectively displaced with the triphenylphosphonium group by dissolving an equimolar amount of N-(1-methoxyalkyl)amide and triphenylphosphonium tetrafluoroborate in CH(2)Cl(2) at room temperature for 30 min, followed by the precipitation of 1-N-(acylamino)alkyltriphenylphosphonium salt with Et(2)O.

Docosahexaenoic acid synthesis from n-3 fatty acid precursors in rat hippocampal neurons.

PubMed

Kaduce, Terry L; Chen, Yucui; Hell, Johannes W; Spector, Arthur A

2008-05-01

Docosahexaenoic acid (DHA), the most abundant n-3 polyunsaturated fatty acid in the brain, has important functions in the hippocampus. To better understand essential fatty acid homeostasis in this region of the brain, we investigated the contributions of n-3 fatty acid precursors in supplying hippocampal neurons with DHA. Primary cultures of rat hippocampal neurons incorporated radiolabeled 18-, 20-, 22-, and 24-carbon n-3 fatty acid and converted some of the uptake to DHA, but the amounts produced from either [1-14C]alpha-linolenic or [1-14C]eicosapentaenoic acid were considerably less than the amounts incorporated when the cultures were incubated with [1-14C]22:6n-3. Most of the [1-14C]22:6n-3 uptake was incorporated into phospholipids, primarily ethanolamine phosphoglycerides. Additional studies demonstrated that the neurons converted [1-14C]linoleic acid to arachidonic acid, the main n-6 fatty acid in the brain. These findings differ from previous results indicating that cerebral and cerebellar neurons cannot convert polyunsaturated fatty acid precursors to DHA or arachidonic acid. Fatty acid compositional analysis demonstrated that the hippocampal neurons contained only 1.1-2.5 mol% DHA under the usual low-DHA culture conditions. The relatively low-DHA content suggests that some responses obtained with these cultures may not be representative of neuronal function in the brain.

Amino Acids in Hemagglutinin Antigenic Site B Determine Antigenic and Receptor Binding Differences between A(H3N2)v and Ancestral Seasonal H3N2 Influenza Viruses

PubMed Central

Wang, Xiaoquan; Ilyushina, Natalia A.; Lugovtsev, Vladimir Y.; Bovin, Nicolai V.; Couzens, Laura K.; Gao, Jin

2016-01-01

ABSTRACT Influenza A H3N2 variant [A(H3N2)v] viruses, which have caused human infections in the United States in recent years, originated from human seasonal H3N2 viruses that were introduced into North American swine in the mid-1990s, but they are antigenically distinct from both the ancestral and current circulating H3N2 strains. A reference A(H3N2)v virus, A/Minnesota/11/2010 (MN/10), and a seasonal H3N2 strain, A/Beijing/32/1992 (BJ/92), were chosen to determine the molecular basis for the antigenic difference between A(H3N2)v and the ancestral viruses. Viruses containing wild-type and mutant MN/10 or BJ/92 hemagglutinins (HAs) were constructed and probed for reactivity with ferret antisera against MN/10 and BJ/92 in hemagglutination inhibition assays. Among the amino acids that differ between the MN/10 and BJ/92 HAs, those in antigenic site A had little impact on the antigenic phenotype. Within antigenic site B, mutations at residues 156, 158, 189, and 193 of MN/10 HA to those in BJ/92 switched the MN/10 antigenic phenotype to that of BJ/92. Mutations at residues 156, 157, 158, 189, and 193 of BJ/92 HA to amino acids present in MN/10 were necessary for BJ/92 to become antigenically similar to MN/10. The HA amino acid substitutions responsible for switching the antigenic phenotype also impacted HA binding to sialyl receptors that are usually present in the human respiratory tract. Our study demonstrates that antigenic site B residues play a critical role in determining both the unique antigenic phenotype and receptor specificity of A(H3N2)v viruses, a finding that may facilitate future surveillance and risk assessment of novel influenza viruses. IMPORTANCE Influenza A H3N2 variant [A(H3N2)v] viruses have caused hundreds of human infections in multiple states in the United States since 2009. Most cases have been children who had contact with swine in agricultural fairs. These viruses originated from human seasonal H3N2 viruses that were introduced into the U

A 2:1 co-crystal of 2-methyl-benzoic acid and N,N'-bis-(pyridin-4-ylmeth-yl)ethanedi-amide: crystal structure and Hirshfeld surface analysis.

PubMed

Syed, Sabrina; Jotani, Mukesh M; Halim, Siti Nadiah Abdul; Tiekink, Edward R T

2016-03-01

The asymmetric unit of the title 2:1 co-crystal, 2C8H8O2·C14H14N4O2, comprises an acid mol-ecule in a general position and half a di-amide mol-ecule, the latter being located about a centre of inversion. In the acid, the carb-oxy-lic acid group is twisted out of the plane of the benzene ring to which it is attached [dihedral angle = 28.51 (8)°] and the carbonyl O atom and methyl group lie approximately to the same side of the mol-ecule [hy-droxy-O-C-C-C(H) torsion angle = -27.92 (17)°]. In the di-amide, the central C4N2O2 core is almost planar (r.m.s. deviation = 0.031 Å), and the pyridyl rings are perpendicular, lying to either side of the central plane [central residue/pyridyl dihedral angle = 88.60 (5)°]. In the mol-ecular packing, three-mol-ecule aggregates are formed via hy-droxy-O-H⋯N(pyrid-yl) hydrogen bonds. These are connected into a supra-molecular layer parallel to (12[Formula: see text]) via amide-N-H⋯O(carbon-yl) hydrogen bonds, as well as methyl-ene-C-H⋯O(amide) inter-actions. Significant π-π inter-actions occur between benzene/benzene, pyrid-yl/benzene and pyrid-yl/pyridyl rings within and between layers to consolidate the three-dimensional packing.

Novel double prodrugs of the iron chelator N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED): Synthesis, characterization, and investigation of activation by chemical hydrolysis and oxidation.

PubMed

Thiele, Nikki A; Abboud, Khalil A; Sloan, Kenneth B

2016-08-08

The development of iron chelators suitable for the chronic treatment of diseases where iron accumulation and subsequent oxidative stress are implicated in disease pathogenesis is an active area of research. The clinical use of the strong chelator N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED) and its alkyl ester prodrugs has been hindered by poor oral bioavailability and lack of conversion to the parent chelator, respectively. Here, we present novel double prodrugs of HBED that have the carboxylate and phenolate donors of HBED masked with carboxylate esters and boronic acids/esters, respectively. These double prodrugs were successfully synthesized as free bases (7a-f) or as dimesylate salts (8a-c,e), and were characterized by (1)H, (13)C, and (11)B NMR; MP; MS; and elemental analysis. The crystal structure of 8a was solved. Three of the double prodrugs (8a-c) were selected for further investigation into their abilities to convert to HBED by stepwise hydrolysis and H2O2 oxidation. The serial hydrolysis of the pinacol and methyl esters of N,N'-bis(2-boronic acid pinacol ester benzyl)ethylenediamine-N,N'-diacetic acid methyl ester dimesylate (8a) was verified by LC-MS. The macro half-lives for the hydrolyses of 8a-c, measured by UV, ranged from 3.8 to 26.3 h at 37 °C in pH 7.5 phosphate buffer containing 50% MeOH. 9, the product of hydrolysis of 8a-c and the intermediate in the conversion pathway, showed little-to-no affinity for iron or copper in UV competition experiments. 9 underwent a serial oxidative deboronation by H2O2 in N-methylmorpholine buffer to generate HBED (k = 10.3 M(-1) min(-1)). The requirement of this second step, oxidation, before conversion to the active chelator is complete may confer site specificity when only localized iron chelation is needed. Overall, these results provide proof of principle for the activation of the double prodrugs by chemical hydrolysis and H2O2 oxidation, and merit further investigation into the

Docosahexaenoic acid at the sn-2 position of structured triacylglycerols improved n-3 polyunsaturated fatty acid assimilation in tissues of hamsters.

PubMed

Bandarra, Narcisa M; Lopes, Paula A; Martins, Susana V; Ferreira, Júlia; Alfaia, Cristina M; Rolo, Eva A; Correia, Jorge J; Pinto, Rui M A; Ramos-Bueno, Rebeca P; Batista, Irineu; Prates, José A M; Guil-Guerrero, José L

2016-05-01

In this study, we hypothesized that the incorporation of docosahexaenoic acid (DHA) in tissues will be higher when it is ingested as triacylglycerols (TAG) structured at the sn-2 position, which enhances efficacy and health benefits of dietary DHA n-3 supplementation. Ten-week-old Golden Syrian male hamsters were randomly allocated into 4 dietary groups with 10 animals in each: linseed oil (LSO; control group), fish oil (FO), fish oil ethyl esters (FO-EE), and structured DHA at the sn-2 position of TAG (DHA-SL). After 12 weeks, there were no variations in the hamsters' body composition parameters across dietary groups. The DHA-SL diet had the lowest values of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total lipids, and aspartate aminotransferase activity, whereas the inverse was observed for the FO diet. Glucose was increased in the LSO diet without affecting insulin and insulin resistance markers. Whereas n-3 polyunsaturated fatty acid was increased in the brain of hamsters fed the DHA-SL diet, higher levels of n-6 polyunsaturated fatty acid were observed in the liver and erythrocytes of the LSO. The highest omega-3 index was obtained with the DHA-SL diet. The principal component analyses discriminated DHA from other metabolites and set apart 4 clusters matching the 4 diets. Similarly, liver, erythrocytes, and brain were separated from each other, pointing toward an individual signature on fatty acid deposition. The structured sn-2 position DHA-containing TAG ameliorated blood lipids and fatty acid incorporation, in particular eicosapentaenoic acid and DHA in liver, erythrocytes, and brain, relative to commercially FOs, thus improving the health benefits of DHA due to its higher bioavailability. Copyright © 2016 Elsevier Inc. All rights reserved.

40 CFR 721.4575 - L-aspartic acid, N,N′- [(1E) - 1,2 - ethenediylbis[(3-sulfo-4, 1-phenylene)imino [6-(phenylamino...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false L-aspartic acid, N,Nâ²- [(1E) - 1,2... Substances § 721.4575 L-aspartic acid, N,N′- [(1E) - 1,2 - ethenediylbis[(3-sulfo-4, 1-phenylene)imino [6... uses subject to reporting. (1) The chemical substance identified as l-aspartic acid, N,N′- [(1E) - 1,2...

Involvement of arginine 878 together with Ca2+ in mouse aminopeptidase A substrate specificity for N-terminal acidic amino-acid residues

PubMed Central

Couvineau, Pierre; de Almeida, Hugo; Maigret, Bernard; Llorens-Cortes, Catherine

2017-01-01

Aminopeptidase A (APA) is a membrane-bound zinc metalloprotease cleaving, in the brain, the N-terminal aspartyl residue of angiotensin II to generate angiotensin III, which exerts a tonic stimulatory effect on the control of blood pressure in hypertensive animals. Using a refined APA structure derived from the human APA crystal structure, we docked the specific and selective APA inhibitor, EC33 in the presence of Ca2+. We report the presence in the S1 subsite of Arg-887 (Arg-878 in mouse APA), the guanidinium moiety of which established an interaction with the electronegative sulfonate group of EC33. Mutagenic replacement of Arg-878 with an alanine or a lysine residue decreased the affinity of the recombinant enzymes for the acidic substrate, α-L-glutamyl-β-naphthylamide, with a slight decrease in substrate hydrolysis velocity either with or without Ca2+. In the absence of Ca2+, the mutations modified the substrate specificity of APA for the acidic substrate, the mutated enzymes hydrolyzing more efficiently basic and neutral substrates, although the addition of Ca2+ partially restored the acidic substrate specificity. The analysis of the 3D models of the Arg-878 mutated APAs revealed a change in the volume of the S1 subsite, which may impair the binding and/or the optimal positioning of the substrate in the active site as well as its hydrolysis. These findings demonstrate the key role of Arg-878 together with Ca2 + in APA substrate specificity for N-terminal acidic amino acid residues by ensuring the optimal positioning of acidic substrates during catalysis. PMID:28877217

Calcium-loaded 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid blocks cell-to-cell diffusion of carboxyfluorescein in staminal hairs of Setcreasea purpurea.

PubMed

Tucker, E B

1990-08-01

The effect of microinjected calcium-loaded 1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (CaBAPTA) on cell-to-cell diffusion of carboxyfluorescein (CF) was examined in staminal hairs of S. purpurea Boom. The CaBAPTA was microinjected into the cytoplasm of the staminal hairs either with CF or prior to a subsequent microinjection of CF. The cell-to-cell diffusion of CF along the hair was monitored using enhanced-fluorescence video microscopy. Cytoplasmic streaming stopped in cells treated with CaBAPTA, indicating that intracellular Ca(2+) had increased. Cell-to-cell diffusion of CF was blocked in cells treated with Ca-BAPTA. An inhibition of cytoplasmic streaming and cell-to-cell diffusion was observed in the cells adjoining the CaBAPTA-microinjected cell, indicating that the Ca-BAPTA appeared to pass through plasmodesmata. While cytoplasmic streaming resumed 5-10 min after CaBAPTA treatment, cell-to-cell diffusion did not resume until 30-120 min later. These data support an involvement of calcium in the regulation of cell-to-cell communication in plants.

Purification and thermal analysis of perfluoro-n-alkanoic acids.

PubMed

Tsuji, Minami; Inoue, Tohru; Shibata, Osamu

2008-01-15

Purification of perfluoro-n-alkanoic acids (C(n)F(2n+1)COOH, n=7, 9, 11, 13, 15 and 17) was made by repeated recrystallizations from n-hexane/acetone mixed solvent, and their purity was found to be more than 99.5% by GC-MS, NMR, and elemental analysis. The thermal behaviors such as melting point and enthalpy change of fusion were investigated using differential scanning calorimetry (DSC). The melting point monotonously increased with increasing carbon number (n) of the acids, while the enthalpy change showed irregularity at n=14. The crystal structure of these acids was found to be dependent upon solvent used for recrystallization; that is, the acids recrystallized from the above solvent becomes more stable energetically, indicating their higher enthalpy change of fusion than that of the solidified acids from fused ones. The solid state was also found to vary depending upon the thermal history, indicating that a few crystal structures of the solid state are quite similar energetically. The melting points (T(m)) of perfluoro-n-alkanoic acids are higher than those of corresponding n-alkanoic acids, and the difference in T(m) increases with increasing carbon number in the acids.

Formation of pyroglutamic acid from N-terminal glutamic acid in immunoglobulin gamma antibodies.

PubMed

Chelius, Dirk; Jing, Kay; Lueras, Alexis; Rehder, Douglas S; Dillon, Thomas M; Vizel, Alona; Rajan, Rahul S; Li, Tiansheng; Treuheit, Michael J; Bondarenko, Pavel V

2006-04-01

The status of the N-terminus of proteins is important for amino acid sequencing by Edman degradation, protein identification by shotgun and top-down techniques, and to uncover biological functions, which may be associated with modifications. In this study, we investigated the pyroglutamic acid formation from N-terminal glutamic acid residues in recombinant monoclonal antibodies. Almost half the antibodies reported in the literature contain a glutamic acid residue at the N-terminus of the light or the heavy chain. Our reversed-phase high-performance liquid chromatography-mass spectrometry method could separate the pyroglutamic acid-containing light chains from the native light chains of reduced and alkylated recombinant monoclonal antibodies. Tryptic peptide mapping and tandem mass spectrometry of the reduced and alkylated proteins was used for the identification of the pyroglutamic acid. We identified the formation of pyroglutamic acid from N-terminal glutamic acid in the heavy chains and light chains of several antibodies, indicating that this nonenzymatic reaction does occur very commonly and can be detected after a few weeks of incubation at 37 and 45 degrees C. The rate of this reaction was measured in several aqueous buffers with different pH values, showing minimal formation of pyroglutamic acid at pH 6.2 and increased formation of pyroglutamic acid at pH 4 and pH 8. The half-life of the N-terminal glutamic acid was approximately 9 months in a pH 4.1 buffer at 45 degrees C. To our knowledge, we showed for the first time that glutamic acid residues located at the N-terminus of proteins undergo pyroglutamic acid formation in vitro.

N-(6-Methylpyridin-2-yl)mesitylenesulfonamide and acetic acid--a salt, a cocrystal or both?

PubMed

Pan, Fangfang; Kalf, Irmgard; Englert, Ulli

2015-08-01

In the solid obtained from N-(6-methylpyridin-2-yl)mesitylenesulfonamide and acetic acid, the constituents interact via two N-H···O hydrogen bonds. The H atom situated in one of these short contacts is disordered over two positions: one of these positions is formally associated with an adduct of the neutral sulfonamide molecule and the neutral acetic acid molecule, and corresponds to a cocrystal, while the alternative site is associated with salt formation between a protonated sulfonamide molecule and deprotonated acetic acid molecule. Site-occupancy refinements and electron densities from difference Fourier maps suggest a trend with temperature, albeit of limited significance; the cocrystal is more relevant at 100 K, whereas the intensity data collected at room temperature match the description as cocrystal and salt equally well.

Plasma n-3 and n-6 fatty acids and inflammatory markers in Chinese vegetarians.

PubMed

Yu, Xiaomei; Huang, Tao; Weng, Xiumei; Shou, Tianxing; Wang, Qiang; Zhou, Xiaoqiong; Hu, Qinxin; Li, Duo

2014-09-29

Polyunsaturated fatty acid (PUFA) intake favorably affects chronic inflammatory-related diseases such as cardiovascular disease; however, the relationship between the PUFA and inflammatory factors in the healthy vegetarians were not clear. We aimed to investigate the plasma fatty acids status, and its association with plasma inflammatory factors in Chinese vegetarians and omnivores. A total of 89 male vegetarians and 106 male omnivores were participated the study. Plasma concentrations of inflammatory factors were detected by ELISA, and as standard methods fatty acids were extracted and determined by chromatography. Compared with omnivores, vegetarians have significant higher interleukin-6 (IL-6), plasma n-6 PUFA, n-6/n-3, and 18:3n-3; while they have significant lower leukotriene B4 (LTB4), cyclo-oxygenase-2 (COX2) and prostaglandin E2 (PGE2), 20:5n-3, 22:5n-3, 22:6n-3, and n-3 PUFA. In vegetarians, plasma 20:4n-6 was significant positively related to TNF-α. LTB4 was significantly positively related to plasma 22:6n-3, and negatively associated with n-6 PUFA. Vegetarians have higher plasma n-6 PUFA and IL-6, but lower LTB4, n-3 PUFA, 22:6n-3, COX2 and PGE2 levels. It would seem appropriate for vegetarians to increase their dietary n-3 PUFA, while reduce dietary n-6 PUFA and thus reduce the risk of chronic inflammatory-related diseases.

N-3 fatty acids reduced trans fatty acids retention and increased docosahexaenoic acid levels in the brain.

PubMed

Lavandera, Jimena Verónica; Saín, Juliana; Fariña, Ana Clara; Bernal, Claudio Adrián; González, Marcela Aída

2017-09-01

The levels of docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6) are critical for the normal structure and function of the brain. Trans fatty acids (TFA) and the source of the dietary fatty acids (FA) interfere with long-chain polyunsaturated fatty acids (LC-PUFA) biosynthesis. The aim of this study was to investigate the effect of TFA supplementation in diets containing different proportions of n-9, n-6, and n-3 FA on the brain FA profile, including the retention of TFA, LC-PUFA levels, and n-6/n-3 PUFA ratios. These parameters were also investigated in the liver, considering that LC-PUFA are mainly bioconverted from their dietary precursors in this tissue and transported by serum to the brain. Also, stearoyl-CoA desaturase-1 (SCD1) and sterol regulatory element-binding protein-1c (SREBP-1c) gene expressions were evaluated. Male CF1 mice were fed (16 weeks) diets containing different oils (olive, corn, and rapeseed) with distinct proportions of n-9, n-6, and n-3 FA (55.2/17.2/0.7, 32.0/51.3/0.9, and 61.1/18.4/8.6), respectively, substituted or not with 0.75% of TFA. FA composition of the brain, liver, and serum was assessed by gas chromatography. TFA were incorporated into, and therefore retained in the brain, liver, and serum. However, the magnitude of retention was dependent on the tissue and type of isomer. In the brain, total TFA retention was lower than 1% in all diets. Dietary n-3 PUFA decreased TFA retention and increased DHA accretion in the brain. The results underscore the importance of the type of dietary FA on the retention of TFA in the brain and also on the changes of the FA profile.

Retinoic acid induction of calcium channel expression in human NT2N neurons.

PubMed

Gao, Z Y; Xu, G; Stwora-Wojczyk, M M; Matschinsky, F M; Lee, V M; Wolf, B A

1998-06-18

Ca2+ channel expression and regulation of intracellular Ca2+ homeostasis were studied during retinoic acid (RA)-induced differentiation of the human teratocarcinoma cell line Ntera 2/C1.D1 (NT2- cells) into NT2N neurons, a unique model of human neurons in culture. The cytosolic Ca2+ level of undifferentiated NT2- cells was low (75 +/- 5 nM) and stable under basal conditions, and it was only marginally decreased (by 9%) upon removal of extracellular Ca2+. After 10 microM RA treatment, NT2- cells were irreversibly differentiated into a phenotype of neuron-like NT2N cells. Cytosolic Ca2+ level of NT2N neurons was higher (106 +/- 14 nM) than that of NT2- cells and spontaneously fluctuated (0.208 +/- 0.038 transients/min) under basal conditions. Although K+ increased 86Rb fluxes in both NT2- cells and NT2N neurons, it only increased cytosolic Ca2+ level in NT2N neurons. The K+-induced increase in cytosolic Ca2+ in NT2N neurons was antagonized by 0.1-10 microM nifedipine or verapamil, 5 microM omega-CgTx GVIA, but not by 1 microM omega-agatoxin IVA, 1 microM omega-agatoxin TK, 1 microM FTX-3.3, or 100 microM Ni+ implicating L- and N-type voltage-dependent Ca2+ channels. In L- and N-type channels, but not in P- and Q-types, mRNAs were expressed in NT2N neurons as well as NT2- cells. Quantitative analysis of L- and N-type Ca2+ protein levels showed major differences between NT2- cells and NT2N neurons. In NT2- cells, N-type Ca2+ channels were undetectable while L-type channels levels were fivefold lower compared to NT2N neurons. Our findings show that L- and N-type channels are expressed during differentiation of NT2- cells into neurons, and that these voltage-dependent Ca2+ channels have a major role in regulating intracellular Ca2+ homeostasis and neuronal excitability. Copyright 1998 Academic Press.

The formation of pyrrolid-2-one-5-carboxylic acid at the N-terminus of immunoglobulin G heavy chain

PubMed Central

Stott, D. I.; Munro, A. J.

1972-01-01

We propose that pyrrolid-2-one-5-carboxyl-tRNA is not involved in the initiation of protein synthesis in eukaryotic cells and that the N-terminal pyrrolid-2-one-5-carboxylic acid group of an IgG (immunoglobulin G) (that secreted by the mouse plasmacytoma Adj PC5) is formed by the enzymic cyclization of the N-terminal glutamine of the heavy chain of the completed IgG molecule and that the cyclization takes place inside the cell. We base these conclusions on the following evidence. (1) Pyrrolidonecarboxyl-tRNA was not found in incorporation experiments with rat liver preparations and [U-14C]-pyrrolidonecarboxylic acid, glutamic acid and glutamine, even though an incorporation extent of less than 2% of the total products could have been detected. (2) Double-labelling experiments showed that less than 8% of the nascent peptides of heavy chains (those obtained by precipitation by the antibody to Fc fragment) began with pyrrolidonecarboxylic acid. (3) Further double-labelling experiments showed that 60–66% of the heavy chains of the completed intracellular IgG molecule began with pyrrolidonecarboxylic acid after both 1 and 5h of labelling. (4) The IgG, after secretion by plasmacytoma Adj PC5, was found to have the sequence [unk]Glu- Val-Gln-Leu- at the N-termini of the heavy chains. PMID:4674626

n-3 fatty acids reduce plasma 20-hydroxyeicosatetraenoic acid and blood pressure in patients with chronic kidney disease.

PubMed

Barden, Anne E; Burke, Valerie; Mas, Emilie; Beilin, Lawrence J; Puddey, Ian B; Watts, Gerald F; Irish, Ashley B; Mori, Trevor A

2015-09-01

Metabolism of arachidonic acid by cytochrome P450 ω-hydroxylase leads to the formation of 20-hydroxyeicosatetraenoic acid (20-HETE) that regulates vascular function, sodium homeostasis and blood pressure (BP). Supplementation with n-3 fatty acids is known to alter arachidonic acid metabolism and reduce the formation of the lipid peroxidation products F2-isoprostanes, but the effect of n-3 fatty acids on 20-HETE has not been studied. We previously reported a significant effect of n-3 fatty acids but not coenzyme Q10 (CoQ) to reduce BP in a double-blind, placebo-controlled intervention, wherein patients with chronic kidney disease (CKD) were randomized to n-3 fatty acids (4 g), CoQ (200 mg), both supplements or control (4 g olive oil), daily for 8 weeks. This study examined the effect of n-3 fatty acids on plasma and urinary 20-HETE in the same study, as well as plasma and urinary F2-isoprostanes, and relate these to changes in BP. Seventy-four patients completed the 8-week intervention. n-3 fatty acids but not CoQ significantly reduced plasma 20-HETE (P = 0.001) and F2-isoprostanes (P < 0.001). In regression models adjusted for BP at baseline, postintervention plasma 20-HETE was a significant predictor of the fall in SBP (P < 0.0001) and DBP (P < 0.0001) after n-3 fatty acids. This is the first report that n-3 fatty acid supplementation reduces plasma 20-HETE in humans and that this associates with reduced BP. These results provide a plausible mechanism for the reduction in BP observed in patients with CKD following n-3 fatty acid supplementation.

Divergent shifts in lipid mediator profile following supplementation with n-3 docosapentaenoic acid and eicosapentaenoic acid.

PubMed

Markworth, James F; Kaur, Gunveen; Miller, Eliza G; Larsen, Amy E; Sinclair, Andrew J; Maddipati, Krishna Rao; Cameron-Smith, David

2016-11-01

In contrast to the well-characterized effects of specialized proresolving lipid mediators (SPMs) derived from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), little is known about the metabolic fate of the intermediary long-chain (LC) n-3 polyunsaturated fatty acid (PUFA) docosapentaenoic acid (DPA). In this double blind crossover study, shifts in circulating levels of n-3 and n-6 PUFA-derived bioactive lipid mediators were quantified by an unbiased liquid chromatography-tandem mass spectrometry lipidomic approach. Plasma was obtained from human subjects before and after 7 d of supplementation with pure n-3 DPA, n-3 EPA or placebo (olive oil). DPA supplementation increased the SPM resolvin D5 n -3DPA (RvD5 n -3DPA ) and maresin (MaR)-1, the DHA vicinal diol 19,20-dihydroxy-DPA and n-6 PUFA derived 15-keto-PG E 2 (15-keto-PGE 2 ). EPA supplementation had no effect on any plasma DPA or DHA derived mediators, but markedly elevated monohydroxy-eicosapentaenoic acids (HEPEs), including the e-series resolvin (RvE) precursor 18-HEPE; effects not observed with DPA supplementation. These data show that dietary n-3 DPA and EPA have highly divergent effects on human lipid mediator profile, with no overlap in PUFA metabolites formed. The recently uncovered biologic activity of n-3 DPA docosanoids and their marked modulation by dietary DPA intake reveals a unique and specific role of n-3 DPA in human physiology.-Markworth, J. F., Kaur, G., Miller, E. G., Larsen, A. E., Sinclair, A. J., Maddipati, K. R., Cameron-Smith, D. Divergent shifts in lipid mediator profile following supplementation with n-3 docosapentaenoic acid and eicosapentaenoic acid. © FASEB.

Synthesis, biological evaluation, and 3D QSAR study of 2-methyl-4-oxo-3-oxetanylcarbamic acid esters as N-acylethanolamine acid amidase (NAAA) inhibitors.

PubMed

Ponzano, Stefano; Berteotti, Anna; Petracca, Rita; Vitale, Romina; Mengatto, Luisa; Bandiera, Tiziano; Cavalli, Andrea; Piomelli, Daniele; Bertozzi, Fabio; Bottegoni, Giovanni

2014-12-11

N-(2-Oxo-3-oxetanyl)carbamic acid esters have recently been reported to be noncompetitive inhibitors of the N-acylethanolamine acid amidase (NAAA) potentially useful for the treatment of pain and inflammation. In the present study, we further explored the structure-activity relationships of the carbamic acid ester side chain of 2-methyl-4-oxo-3-oxetanylcarbamic acid ester derivatives. Additional favorable features in the design of potent NAAA inhibitors have been found together with the identification of a single digit nanomolar inhibitor. In addition, we devised a 3D QSAR using the atomic property field method. The model turned out to be able to account for the structural variability and was prospectively validated by designing, synthesizing, and testing novel inhibitors. The fairly good agreement between predictions and experimental potency values points to this 3D QSAR model as the first example of quantitative structure-activity relationships in the field of NAAA inhibitors.

Metabolism of vertebrate amino sugars with N-glycolyl groups: resistance of α2-8-linked N-glycolylneuraminic acid to enzymatic cleavage.

PubMed

Davies, Leela R L; Pearce, Oliver M T; Tessier, Matthew B; Assar, Siavash; Smutova, Victoria; Pajunen, Maria; Sumida, Mizuki; Sato, Chihiro; Kitajima, Ken; Finne, Jukka; Gagneux, Pascal; Pshezhetsky, Alexey; Woods, Robert; Varki, Ajit

2012-08-17

The sialic acid (Sia) N-acetylneuraminic acid (Neu5Ac) and its hydroxylated derivative N-glycolylneuraminic acid (Neu5Gc) differ by one oxygen atom. CMP-Neu5Gc is synthesized from CMP-Neu5Ac, with Neu5Gc representing a highly variable fraction of total Sias in various tissues and among different species. The exception may be the brain, where Neu5Ac is abundant and Neu5Gc is reported to be rare. Here, we confirm this unusual pattern and its evolutionary conservation in additional samples from various species, concluding that brain Neu5Gc expression has been maintained at extremely low levels over hundreds of millions of years of vertebrate evolution. Most explanations for this pattern do not require maintaining neural Neu5Gc at such low levels. We hypothesized that resistance of α2-8-linked Neu5Gc to vertebrate sialidases is the detrimental effect requiring the relative absence of Neu5Gc from brain. This linkage is prominent in polysialic acid (polySia), a molecule with critical roles in vertebrate neural development. We show that Neu5Gc is incorporated into neural polySia and does not cause in vitro toxicity. Synthetic polymers of Neu5Ac and Neu5Gc showed that mammalian and bacterial sialidases are much less able to hydrolyze α2-8-linked Neu5Gc at the nonreducing terminus. Notably, this difference was not seen with acid-catalyzed hydrolysis of polySias. Molecular dynamics modeling indicates that differences in the three-dimensional conformation of terminal saccharides may partly explain reduced enzymatic activity. In keeping with this, polymers of N-propionylneuraminic acid are sensitive to sialidases. Resistance of Neu5Gc-containing polySia to sialidases provides a potential explanation for the rarity of Neu5Gc in the vertebrate brain.

Can long chain n-3 fatty acids from feed be converted into very long chain n-3 fatty acids in fillets from farmed rainbow trout (Oncorhynchus mykiss)?

NASA Astrophysics Data System (ADS)

Lušnic Polak, M.; Demšar, L.; Luzar, U.; Polak, T.

2017-09-01

The link between the basic chemical and fatty acid composition of trout feed on one hand and trout (Oncorhynchus mykiss) meat (fillet) was investigated.. The content of 52 fatty acids from feed and trout meat lipids was determined by in-situ transesterification and capillary column gas-liquid chromatography. On average, 100 g of trout feed contained 7.4 g of moisture, 47.7 g of proteins, 6.09 g of ash, 21.4 g of fat, and as for fatty acid composition, 47.8 wt. % were monounsaturated, 34.0 wt. % were polyunsaturated and 18.1 wt. % were saturated fatty acids, with the PS ratio 1.88, n-6/n-3 ratio 1.74, 0.80 wt. % of trans and 3.28 wt. % of very long chain n-3 fatty acids. On average, 100 g of trout meat contained 76.1 g of moisture, 21.4 g of proteins, 1.34 g of ash, 2.52 g of fat, and in the fatty acid composition 42.1 wt. % were monounsaturated, 38.2 wt. % were polyunsaturated and 18.9 wt. % were saturated fatty acids, with the PS ratio 2.02, n-6/n-3 ratio 0.98, 0.95 wt. % of trans and 13.25 wt. % of very long chain n-3 fatty acids.

Crystal Structure and Antitumor Activity of the Novel Zwitterionic Complex of tri-n-Butyltin(IV) with 2-Thiobarbituric Acid

PubMed Central

Balas, Vasilios I.; Hadjikakou, Sotiris K.; Hadjiliadis, Nick; Kourkoumelis, Nikolaos; Light, Mark E.; Hursthouse, Mike; Metsios, Apostolos K.; Karkabounas, Spyros

2008-01-01

A novel tri-n-butyl(IV) derivative of 2-thiobarbituric acid (HTBA) of formula [(n-Bu)3Sn(TBA) H2O] (1) has been synthesized and characterized by elemental analysis and 119Sn-NMR and FT-IR spectroscopic techniques. The crystal structure of complex 1 has been determined by single crystal X-ray diffraction analysis at 120(2) K. The geometry around Sn(IV) is trigonal bipyramidal. Three n-butyl groups and one oxygen atom from a deprotonated 2-thiobarbituric ligand are bonded to the metal center. The geometry is completed with one oxygen from a water molecule. Compound 1 exhibits potent, in vitro, cytotoxicity against sarcoma cancer cells (mesenchymal tissue) from the Wistar rat, polycyclic aromatic hydrocarbons (PAH, benzo[a]pyrene) carcinogenesis. In addition, the inhibition caused by 1, in the rate of lipoxygenase (LOX) catalyzed oxidation reaction of linoleic acid to hyperoxolinoleic acid, has been also kinetically and theoretically studied. The results are compared to that of cisplatin. PMID:18401456

Fluorescence properties of Schiff base - N,N‧-bis(salicylidene) - 1,2-Phenylenediamine in presence of bile acid host

NASA Astrophysics Data System (ADS)

Roy, Nayan; Paul, Pradip C.; Singh, T. Sanjoy

2015-05-01

Fluorescence properties of Schiff base - N,N‧-bis(salicylidene) - 1,2-phenylenediamine (LH2) is used to study the micelles formed by aggregation of different important bile acids like cholic acid, deoxycholic acid, chenodeoxycholic acid and glycocholic acid by steady state and picosecond time-resolved fluorescence spectroscopy. The fluorescence band intensity was found out to increase with concomitant red shift with gradual addition of different bile acids. Binding constant of the probe with different bile acids as well as critical micelle concentration was obtained from the variation of fluorescence intensity on increasing concentration of bile acids in the medium. The increase in fluorescence quantum yields, fluorescence decay times and substantial decrease in nonradiative decay rate constants in bile acids micellar environment points to the restricted motion of the fluorophore inside the micellar subdomains.

Fatty acid and sn-2 fatty acid composition in human milk from Granada (Spain) and in infant formulas.

PubMed

López-López, A; López-Sabater, M C; Campoy-Folgoso, C; Rivero-Urgell, M; Castellote-Bargalló, A I

2002-12-01

To investigate differences in fatty acid and sn-2 fatty acid composition in colostrum, transitional and mature human milk, and in term infant formulas. Departament de Nutrició i Bromatologia, University of Barcelona, Spain and University Hospital of Granada, Spain. One-hundred and twenty mothers and 11 available types of infant formulas for term infants. We analysed the fatty acid composition of colostrum (n=40), transitional milk (n=40), mature milk (n=40) and 11 infant formulas. We also analysed the fatty acid composition at sn-2 position in colostrum (n=12), transitional milk (n=12), mature milk (n=12), and the 11 infant formulas. Human milk in Spain had low saturated fatty acids, high monounsaturated fatty acids and high linolenic acid. Infant formulas and mature human milk had similar fatty acid composition. In mature milk, palmitic acid was preferentially esterified at the sn-2 position (86.25%), and oleic and linoleic acids were predominantly esterified at the sn-1,3 positions (12.22 and 22.27%, respectively, in the sn-2 position). In infant formulas, palmitic acid was preferentially esterified at the sn-1,3 positions and oleic and linoleic acids had higher percentages at the sn-2 position than they do in human milk. Fatty acid composition of human milk in Spain seems to reflect the Mediterranean dietary habits of mothers. Infant formulas resemble the fatty acid profile of human milk, but the distribution of fatty acids at the sn-2 position is markedly different.

Biodegradable hydrogel derived from cellulose acetate and EDTA as a reduction substrate of leaching NPK compound fertilizer and water retention in soil.

PubMed

Senna, André M; Botaro, Vagner R

2017-08-28

To study the behavior of a biodegradable hydrogel derived from cellulose acetate and ethylenediaminetetraacetic dianhydride (EDTAD), as a reduction substrate of NPK fertilizer in soil. The biodegradable hydrogel (HEDTA) was prepared from cellulose acetate (CA) with a degree substitution (DS) 2.5 by esterification crosslinking with EDTAD catalyzed by triethylamine. We systematically investigated the performance of the HEDTA in the reducing NPK (Ammonium, phosphate and potassium) fertilizer leaching. We also compare the percentage of leaching between the HEDTA and commercial fertilizers. To characterize the esterification and crosslinking between CA and EDTAD, FTIR spectroscopy and thermogravimetric analysis (DTG) were employed. The biodegradation experiments were carried out in simulated soil (23% of sand, 23% of cattle manure, 23% of soil and 31% of water) and the HEDTA was tested in the eucalyptus planting during the dry season in the São Paulo state, Brazil. The HEDTA was able to reduce the leaching of fertilizers and improve the performance of eucalyptus seedlings and reduced the mortality of the seedlings. The HEDTA showed to be an excellent substrate for slow release and water-retention in soil, reducer of the fertilizers leaching, in addition being nontoxic, biodegradable in the soil and environmentally-friendly. Copyright © 2017 Elsevier B.V. All rights reserved.

In vitro cytotoxicity and differential cellular sensitivity of derivatives of diamino acids. II. N1-methyl, N1-allyl, N1-(2-chloroethyl) and N1-propargyl nitrosoureas.

PubMed

Dulude, H; Salvador, R; Gallant, G

1995-01-01

The in vitro cytotoxicity and differential cellular sensitivity of a series of new N1-methyl, N1-allyl, N1-2-chloroethyl and N1-propargyl nitrosourea derivatives of diamino acids were determined in the National Cancer Institute's primary antitumor drug screen. The compounds tested showed an in vitro anticancer activity similar to commercialized nitrosoureas such as CCNU, BCNU, MeCCNU, chlorozotocin, streptozotocin and PCNU. The alkylating moiety of the nitrosoureas seems to play a role in the general selectivity of our compounds. The N1-methyl and N1-2-chloroethyl nitrosourea derivatives are more selective for central nervous system cell lines, the N1-allyl nitrosourea derivatives are more selective for lung cancer cell lines and the N1-propargyl nitrosoureas are more selective for leukemia cell lines.

Rapid acquisition adaptive amino acid substitutions involved in the virulence enhancement of an H1N2 avian influenza virus in mice.

PubMed

Yu, Zhijun; Sun, Weiyang; Zhang, Xinghai; Cheng, Kaihui; Zhao, Chuqi; Xia, Xianzhu; Gao, Yuwei

2017-08-01

Although H1N2 avian influenza virus (AIV) only infect birds, documented cases of swine infection with H1N2 influenza viruses suggest this subtype AIV may pose a potential threat to mammals. Here, we generated mouse-adapted variants of a H1N2 AIV to identify adaptive changes that increased virulence in mammals. MLD 50 of the variants were reduced >1000-fold compared to the parental virus. Variants displayed enhanced replication in vitro and in vivo, and replicate in extrapulmonary organs. These data show that enhanced replication capacity and expanded tissue tropism may increase the virulence of H1N2 AIV in mice. Sequence analysis revealed multiple amino acid substitutions in the PB2 (L134H, I647L, and D701N), HA (G228S), and M1 (D231N) proteins. These results indicate that H1N2 AIV can rapidly acquire adaptive amino acid substitutions in mammalian hosts, and these amino acid substitutions collaboratively enhance the ability of H1N2 AIV to replicate and cause severe disease in mammals. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of a hybrid-smectite nanomaterial formed by immobilizing of N-pyridin-2-ylmethylsuccinamic acid onto (3-aminopropyl)triethoxysilane modified smectite and its potentiometric sensor application

NASA Astrophysics Data System (ADS)

Topcu, Cihan; Caglar, Sema; Caglar, Bulent; Coldur, Fatih; Cubuk, Osman; Sarp, Gokhan; Gedik, Kubra; Bozkurt Cirak, Burcu; Tabak, Ahmet

2016-09-01

A novel N-pyridin-2-ylmethylsuccinamic acid-functionalized smectite nanomaterial was synthesized by immobilizing of N-pyridin-2-ylmethylsuccinamic acid through chemical bonding onto (3-aminopropyl)triethoxysilane modified smectite. The structural, thermal, morphological and surface properties of raw, silane-grafted and the N-pyridin-2-ylmethylsuccinamic acid-functionalized smectites were investigated by various characterization techniques. The thermal analysis data showed the presence of peaks in the temperature range from 200 °C to 600 °C due to the presence of physically adsorbed silanes, intercalated silanes, surface grafted silanes and chemically grafted silane molecules between the smectite layers. The powder x-ray diffraction patterns clearly indicated that the aminopropyl molecules also intercalated into the smectite interlayers as bilayer arrangement whereas N-pyridin-2-ylmethylsuccinamic acid molecules were only attached to 3-aminopropyltriethoxysilane molecules on the external surface and edges of clay and they did not intercalate. Fourier transform infrared spectroscopy confirms N-pyridin-2-ylmethylsuccinamic acid molecules bonding through the amide bond between the amine group of aminopropyltriethoxysilane molecules and a carboxylic acid functional group of N-pyridin-2-ylmethylsuccinamic acid molecules. The guest molecules functionalized onto the smectite caused significant alterations in the textural and morphological parameters of the raw smectite. The anchoring of N-pyridin-2-ylmethylsuccinamic acid molecules led to positive electrophoretic mobility values when compared to starting materials. N-pyridin-2-ylmethylsuccinamic acid-functionalized smectite was employed as an electroactive ingredient in the structure of potentiometric PVC-membrane sensor. The sensor exhibited more selective potentiometric response towards chlorate ions compared to the other common anionic species.

H9N2-specific IgG and CD4+CD25+ T cells in broilers fed a diet supplemented with organic acids.

PubMed

Lee, In Kyu; Bae, Suhan; Gu, Min Jeong; You, Sun Jong; Kim, Girak; Park, Sung-Moo; Jeung, Woon-Hee; Ko, Kwang Hyun; Cho, Kyung Jin; Kang, Jung Sun; Yun, Cheol-Heui

2017-05-01

Organic acids have long been known for their beneficial effects on growth performance in domestic animals. However, their impact on immune responses against viral antigens in chickens is unclear. The present study aimed to investigate immunological parameters in broilers immunized with a H9N2 vaccine and/or fed a diet containing organic acids (citric, formic, and lactic acids). We allotted 1-day-old broilers into 4 groups: control (C), fed a diet supplemented with organic acids (O), administered a H9N2 vaccine (V), and fed a diet supplemented with organic acids and administered a H9N2 vaccine (OV). Blood and spleen samples were taken at 2, 7 and 14 d post vaccination (DPV). At 14 DPV, total and H9N2-specific IgG levels were significantly lower in the OV group than in the V group. However, it was intriguing to observe that at 2 DPV, the percentage of CD4+CD25+ T cells was significantly higher in the OV group than in the other groups, indicating the potential induction of regulatory T cells by organic acids. In contrast, at 2 DPV, the percentage of CD4+CD28+ T cells were significantly lower in the OV group than in the other groups, suggesting that CD28 molecules are down-regulated by the treatment. The expression of CD28 on CD4+ T cells, up-regulated by the stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Iono), was inhibited upon organic acid treatment in OV group. In addition, the proliferation of lymphocytes, stimulated with formalin-inactivated H9N2, was significantly higher in the V group than in the OV group. Alpha 1-acid glycoprotein (AGP) production was significantly lower in the OV group than in the V group, suggesting that the organic acids inhibited the inflammation caused by the vaccination. Overall, induction of regulatory CD4+CD25+ T cells, coinciding with the decrease of H9N2-specific antibodies, was observed in broilers fed organic acids. © 2016 Poultry Science Association Inc.

Thermodynamic and Spectroscopic Studies of Trivalent f -element Complexation with Ethylenediamine- N,N '-di(acetylglycine)- N,N '-diacetic Acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heathman, Colt R.; Grimes, Travis S.; Zalupski, Peter R.

In this study, the coordination behavior and thermodynamic features of complexation of trivalent lanthanides and americium by ethylenediamine- N,N'-di(acetylglycine)- N,N'-diacetic acid (EDDAG-DA) (bisamide-substituted-EDTA) were investigated by potentiometric and spectroscopic techniques. Acid dissociation constants (K a) and complexation constants (β) of lanthanides (except Pm) were determined by potentiometric analysis. Absorption spectroscopy was used to determine stability constants for the binding of trivalent americium and neodymium by EDDAG-DA under similar conditions. The potentiometry revealed 5 discernible protonation constants and 3 distinct metal–ligand complexes (identified as ML –, MHL, and MH 2L +). Time-resolved fluorescence studies of Eu-(EDDAG-DA) solutions (at varying pH) identifiedmore » a constant inner-sphere hydration number of 3, suggesting that glycine functionalities contained in the amide pendant arms are not involved in metal complexation and are protonated under more acidic conditions. The thermodynamic studies identified that f-element coordination by EDDAG-DA is similar to that observed for ethylenediamine- N,N,N',N'-tetraacetic acid (EDTA). However, coordination via two amidic oxygens of EDDAG-DA lowers its trivalent f-element complex stability by roughly 3 orders of magnitude relative to EDTA.« less

Thermodynamic and Spectroscopic Studies of Trivalent f -element Complexation with Ethylenediamine- N,N '-di(acetylglycine)- N,N '-diacetic Acid

DOE PAGES

Heathman, Colt R.; Grimes, Travis S.; Zalupski, Peter R.

2016-03-21

In this study, the coordination behavior and thermodynamic features of complexation of trivalent lanthanides and americium by ethylenediamine- N,N'-di(acetylglycine)- N,N'-diacetic acid (EDDAG-DA) (bisamide-substituted-EDTA) were investigated by potentiometric and spectroscopic techniques. Acid dissociation constants (K a) and complexation constants (β) of lanthanides (except Pm) were determined by potentiometric analysis. Absorption spectroscopy was used to determine stability constants for the binding of trivalent americium and neodymium by EDDAG-DA under similar conditions. The potentiometry revealed 5 discernible protonation constants and 3 distinct metal–ligand complexes (identified as ML –, MHL, and MH 2L +). Time-resolved fluorescence studies of Eu-(EDDAG-DA) solutions (at varying pH) identifiedmore » a constant inner-sphere hydration number of 3, suggesting that glycine functionalities contained in the amide pendant arms are not involved in metal complexation and are protonated under more acidic conditions. The thermodynamic studies identified that f-element coordination by EDDAG-DA is similar to that observed for ethylenediamine- N,N,N',N'-tetraacetic acid (EDTA). However, coordination via two amidic oxygens of EDDAG-DA lowers its trivalent f-element complex stability by roughly 3 orders of magnitude relative to EDTA.« less

Interaction between Marine-Derived n-3 Long Chain Polyunsaturated Fatty Acids and Uric Acid on Glucose Metabolism and Risk of Type 2 Diabetes Mellitus: A Case-Control Study.

PubMed

Li, Kelei; Wu, Kejian; Zhao, Yimin; Huang, Tao; Lou, Dajun; Yu, Xiaomei; Li, Duo

2015-08-26

The present case-control study explored the interaction between marine-derived n-3 long chain polyunsaturated fatty acids (n-3 LC PUFAs) and uric acid (UA) on glucose metabolism and risk of type 2 diabetes mellitus (T2DM). Two hundred and eleven healthy subjects in control group and 268 T2DM subjects in case group were included. Plasma phospholipid (PL) fatty acids and biochemical parameters were detected by standard methods. Plasma PL C22:6n-3 was significantly lower in case group than in control group, and was negatively correlated with fasting glucose (r = -0.177, p < 0.001). Higher plasma PL C22:6n-3 was associated with lower risk of T2DM, and the OR was 0.32 (95% confidence interval (CI), 0.12 to 0.80; p = 0.016) for per unit increase of C22:6n-3. UA was significantly lower in case group than in control group. UA was positively correlated with fasting glucose in healthy subjects, but this correlation became negative in T2DM subjects. A significant interaction was observed between C22:6n-3 and UA on fasting glucose (p for interaction = 0.005): the lowering effect of C22:6n-3 was only significant in subjects with a lower level of UA. In conclusion, C22:6n-3 interacts with UA to modulate glucose metabolism.

Development of N(2) Sensor for Determination of PN(2) in Body Tissues.

DTIC Science & Technology

1986-08-01

NK3)4C1 2 ]Cl Acid -140 -340 Acid -120 -280 +500 . + Zn Amalgam +700 +900 2 cis-Ru(N( 3 )4C1 2 C1 Buffer -130 -305 (major) ,450 + Zn Amalgam -210...increase under N 2 -400 mV under N 2 cis- [1u (en) 2C12 )C1 Buffer -125 -350 Buffer + Zn - so -400 .475 Amalgam +780 cis-(Ru(en)2Br 2 ] r Acid -120...375 Acid + Zn - 0 -280 plateau Amalgam 600-8SO cis- ([ (bipyr)C12 1Cl Buffer .455 +320 Buffer + Zn +575 +380 Nme Amalgam 1Acid = 0.1M H2SO42Buffer

Comparison of PFDA (Perfluoro-n-Decanoic Acid) and TCDD on Heart Membranes.

DTIC Science & Technology

1986-06-18

AD-A171 960 COMPARISON OF PFDA ( PERFLUORO -N-DECANOIC ACID) AND TCDD 1/1 ON HEART NEMBRANES(U) WRIGHT STATE UNIY DAYTON OH SCHOOL OF MEDICINE A E...1986) Toxicol. Appl. Pharmacol. Perfluoro -n-decanoic acid ( PFDA ) is a synthetic chemical resembling a 10 carbon fatty acid. Several studies have...3 INTRODUCTION Perfluoro -n-decanoic acid ( PFDA ; nonadecafluorodecanoic acid, C10 F19 0 2H) is a straight-chain 10 carbon carboxylic acid with fluorine

Spectrophotometric Determination of Nitrogen Oxides in the Air with 2-N-Ethyl-5-Naphthol-7-Sulfonic Acid

NASA Astrophysics Data System (ADS)

Huang, Y.; Shi, W.; Zhang, C.; Wen, H.

2017-09-01

For the determination of nitrogen oxides in the air, the structure of diazo and coupling compounds was studied and tested by experiments. The conditions and methods of diazo and coupling reactions were investigated. Furthermore, a spectrophotometric method using sulfanilamide as a diazo compound and 2-N-ethyl-5-naphthol-7-sulfonic acid (N-ethyl J acid) as a coupling compound was proposed. The maximum absorption wavelength of sulfanilamide-Nethyl J acid azo compound was at 478 nm. The molar absorptivity was 4.31 × 104 L/(mol × cm) with a recovery of 98.7-100.9% and RSD of 1.85%. For nitrogen oxides, the determinate limit of this measurement was 0.015 mg/m3 and the determinate range 0.024-2.0 mg/m3. Moreover, a high degree of correlation was observed between the results obtained by the proposed method and the standard methods. The proposed method can be easily applied to determine nitrogen oxides in the air.

The effects of n-3 long-chain polyunsaturated fatty acid supplementation on AGEs and sRAGE in type 2 diabetes mellitus.

PubMed

Kurt, Asuman; Andican, Gülnur; Siva, Zeynep Oşar; Andican, Ahat; Burcak, Gülden

2016-12-01

In diabetes mellitus, chronic hyperglycemia leads to formation of advanced glycation end products (AGEs). Binding of AGEs to receptors of AGE (RAGE) causes deleterious effects. In populations with a high consumption of n-3 long-chain polyunsaturated fatty acids, a lower prevalence of diabetes mellitus has been reported. We aimed to investigate the effects of n-3 fatty acid (EPA and DHA) supplementation on the levels of AGEs (carboxymethyl lysine (CML) and pentosidine), sRAGE, and nuclear factor kappa B (NF-kB) in type 2 diabetes mellitus (T2DM). T2DM patients (n = 38) treated with oral hypoglycemic agents, without insulin were supplemented with n-3 fatty acids (1.2 g/day) for 2 months. Plasma CML, pentosidine, sRAGE, and NF-kB levels were measured by ELISA both before and after the supplementation. n-3 fatty acid supplementation significantly reduced fasting glucose (p < 0.01), glycated hemoglobin (HbA 1c ) (p < 0.05), and pentosidine (p < 0.05) levels. The supplementation induced percentage changes in pentosidine and HbA 1c and in pentosidine and creatinine were observed to be correlated (r = 0.349, p < 0.05) and (r = 0.377, p < 0.05), respectively. Waist circumference and systolic and diastolic pressures were significantly decreased due to n-3 supplementation (p < 0.001, p < 0.01, p < 0.01), respectively. Our results show that supplementation with n-3 fatty acid has beneficial effects on waist circumference; systolic and diastolic blood pressures; and the levels of glucose, HbA 1c , and pentosidine in T2DM patients. However, the supplementation failed to decrease these parameters to the reference ranges for healthy subjects. In addition, the supplementation did not appear to induce any significant differences in CML, sRAGE, or NF-kB.

Association of fish and n-3 fatty acid intake with the risk of type 2 diabetes: a meta-analysis of prospective studies.

PubMed

Zhou, Yunping; Tian, Changwei; Jia, Chongqi

2012-08-01

Results from observational studies on the association of fish and n-3 fatty acid consumption with type 2 diabetes mellitus (T2DM) risk are conflicting. Hence, a meta-analysis was performed to investigate this association from cohort studies. A comprehensive search was then conducted to identify cohort studies on the association of fish and/or n-3 fatty acid intake with T2DM risk. In the highest v. lowest categorical analyses, the fixed or random-effect model was selected based on the homogeneity test among studies. Linear and non-linear dose-response relationships were also assessed by univariate and bivariate random-effect meta-regression with restricted maximum likelihood estimation. In the highest v. lowest categorical analyses, the pooled relative risk (RR) of T2DM for intake of fish and n-3 fatty acid was 1·146 (95 % CI 0·975, 1·346) and 1·076 (95 % CI 0·955, 1·213), respectively. In the linear dose-response relationship, the pooled RR for an increment of one time (about 105 g)/week of fish intake (four times/month) and of 0·1 g/d of n-3 fatty acid intake was 1·042 (95 % CI 1·026, 1·058) and 1·057 (95 % CI 1·042, 1·073), respectively. The significant non-linear dose-response associations of fish and n-3 fatty acid intake with T2DM risk were not observed. The present evidence from observational studies suggests that the intake of both fish and n-3 fatty acids might be weakly positively associated with the T2DM risk. Further studies are needed to confirm these results.

Echium oil is better than rapeseed oil in enriching poultry meat with n-3 polyunsaturated fatty acids, including eicosapentaenoic acid and docosapentaenoic acid.

PubMed

Kitessa, Soressa M; Young, Paul

2009-03-01

alpha-Linolenic acid (ALA; 18 : 3n-3) and stearidonic acid (SDA; 18 : 4n-3) are on the biosynthetic pathway of EPA (20 : 5n-3) and DHA (22 : 6n-3). The n-3 fatty acid in rapeseed oil is ALA while Echium oil contains both ALA and SDA. To determine the comparative efficacy of ALA- and SDA-rich oils in enriching broiler meat with n-3 PUFA, we offered diets supplemented with rapeseed oil (rapeseed group) or Echium oil (Echium group) for 35 d to two groups of chicks (age 21 d). There were no differences in carcass weight (2.20 (sem 0.06) v. 2.23 (sem 0.05) kg), boned, skinless thigh muscle (494 (sem 20.5) v. 507 (sem 16.7) g), boned, skinless breast muscle (553 (sem 13.4) v. 546 (sem 11.6) g) or organ weights (heart, liver and gizzard) between the two groups. The total intramuscular fat (IMF) percentage of thigh (8.0 (sem 0.64) v. 8.1 (sem 0.62) %) and breast muscles (2.3 (sem 0.24) v. 2.0 (sem 0.19) %) were also similar between the groups. In contrast, the concentrations of most of the individual n-3 fatty acids (ALA, SDA, EPA and docosapentaenoic acid) were all higher in the Echium than the rapeseed group (P < 0.05). However, differences in DHA concentrations were significant in breast but not thigh muscle IMF. The total n-3 yields/100 g serve thigh muscle were 265 and 676 mg for the rapeseed and Echium groups, respectively (P < 0.0001). The corresponding values for equivalent breast muscles were 70 and 137 mg, respectively (P < 0.01). We conclude that Echium oil is a better lipid supplement than rapeseed oil in changing the concentration and yield of n-3 fatty acids, except DHA, in broiler meat.

Synthesis and Anti-microbial Activity of Novel Phosphatidylethanolamine-N-amino Acid Derivatives.

PubMed

Vijeetha, Tadla; Balakrishna, Marrapu; Karuna, Mallampalli Sri Lakshmi; Surya Koppeswara Rao, Bhamidipati Venkata; Prasad, Rachapudi Badari Narayana; Kumar, Koochana Pranay; Surya Narayana Murthy, Upadyaula

2015-01-01

The study involved synthesis of five novel amino acid derivatives of phosphatidylethanolamine isolated from egg yolk lecithin employing a three step procedure i) N-protection of L-amino acids with BOC anhydride in alkaline medium ii) condensation of - CO2H group of N-protected amino acid with free -NH2 of PE by a peptide linkage and iii) deprotection of N-protected group of amino acids to obtain phosphatidylethanolamine-N-amino acid derivatives in 60-75% yield. The five L-amino acids used were L glycine, L-valine, L-leucine, L-isoleucine and L-phenylalanine. The amino acid derivatives were screened for anti-baterial activity against B. subtilis, S. aureus, P. aeroginosa and E. coli taking Streptomycin as reference compound and anti-fungal activity against C. albicans, S. cervisiae, A. niger taking AmphotericinB as reference compound. All the amino acid derivatives exhibited extraordinary anti-bacterial activities about 3 folds or comparable to Streptomycin and moderate or no anti-fungal activity against Amphotericin-B.

Regioselective Copper-Catalyzed Amination of Chlorobenzoic Acids: Synthesis and Solid-State Structures of N-Aryl Anthranilic Acid Derivatives

PubMed Central

Mei, Xuefeng; August, Adam T.; Wolf, Christian

2008-01-01

A chemo- and regioselective copper-catalyzed cross-coupling reaction for effective amination of 2-chlorobenzoic acids with aniline derivatives has been developed. The method eliminates the need for acid protection and produces a wide range of N-aryl anthranilic acid derivatives in up to 99%. The amination was found to proceed with both electron-rich and electron-deficient aryl chlorides and anilines and also utilizes sterically hindered anilines such as 2,6-dimethylaniline and 2-tert-butylaniline. The conformational isomerism of appropriately substituted N-aryl anthranilic acids has been investigated in the solid state. Crystallographic analysis of seven anthranilic acid derivatives showed formation of two distinct supramolecular architectures exhibiting trans-anti- and unprecedented trans-syn-dimeric structures. PMID:16388629

'Designer oils' low in n-6:n-3 fatty acid ratio beneficially modifies cardiovascular risks in mice.

PubMed

Riediger, Natalie D; Azordegan, Nazila; Harris-Janz, Sydney; Ma, David W L; Suh, Miyoung; Moghadasian, Mohammed H

2009-08-01

Cardiovascular benefits of dietary n-3 fatty acids have been shown. However, benefits of n-3 fatty acids as part of a high fat, low n-6:n-3 fatty acid ratio diet has not been fully characterized. Aim of this study is to investigate cardiovascular and metabolic benefits of 'designer oils' containing a low ratio of n-6:n-3 fatty acids in C57BL/6 mice. Three groups of C57BL/6 mice were fed an atherogenic diet supplemented with either a fish oil- or flaxseed oil-based 'designer oil' with an approximate n-6:n-3 fatty acid ratio of 2:1 (treated groups, n = 6 each) or with a safflower oil-based formulation with a high ratio (25:1) of n-6:n-3 fatty acids (control group, n = 6) for 6 weeks. Food intake, body weight, and blood lipid levels were monitored regularly. Fatty acid profile of the heart tissues was assessed. Histological assessment of liver samples was conducted. At the end of the study body weight and food intake was significantly higher in the flax group compared to control. The levels of 20:5n-3 and 22:6n-3 was significantly increased in the heart phospholipids in both flax and fish groups compared to control; tissue 20:4n-6 was significantly reduced in the fish group compared to control. Significant liver pathology was observed in the control group only. Lowering dietary ratio of n-6:n-3 fatty acids may significantly reduce cardiovascular and metabolic risks in mice regardless of the source of n-3 fatty acids.

Differential effects of n-3 polyunsaturated fatty acids on metabolic control and vascular reactivity in the type 2 diabetic ob/ob mouse.

PubMed

Mustad, Vikkie A; Demichele, Stephen; Huang, Yung-Sheng; Mika, Amanda; Lubbers, Nathan; Berthiaume, Nathalie; Polakowski, Jim; Zinker, Brad

2006-10-01

Diets rich in monounsaturated fatty acids (MUFA) are recommended for individuals with type 2 diabetes mellitus (T2DM). The American Heart Association recommends increasing intakes of n-3 polyunsaturated fatty acids (PUFA) to reduce the risk of vascular disease in high-risk individuals; however, the long-term effects of these bioactive fatty acids on glucose metabolism in insulin resistance are controversial. The present studies were conducted to evaluate the effects of diets rich in both MUFA and alpha linolenic acid (C18:3n-3, ALA), eicosapentaenoic acid (C20:5n-3, EPA), or docosahexaenoic acid (C22:6n-3, DHA), on glycemic control and other parameters related to vascular health in a mouse model of T2DM and insulin resistance. Male ob/ob mice (n = 15 per treatment) were fed 1 of 4 lipid-modified formula diets (LFDs) for 4 weeks: (1) MUFA control, (2) ALA blend, (3) EPA blend, and (4) DHA blend. A portion of a MUFA-rich lipid blend in the control LFD was replaced with 11% to 14% energy as n-3 PUFA. After 4 weeks, plasma glucose response to a standard meal (1.5 g carbohydrate/kg body weight) and insulin challenge (2 U/kg body weight, IP) was assessed, and samples were collected for analysis of glucose, insulin, and lipids. Vascular reactivity of isolated aortic rings was assessed in an identical follow-up study. The results showed that insulin-resistant mice fed an LFD with EPA and/or DHA blends had significantly (P < .05) lower triglycerides and free fatty acids, but insulin sensitivity and fasting plasma glucose were not improved. However, mice fed with the ALA blend had significantly improved insulin sensitivity when compared to those fed with other LFD (P < .05). Animals fed an LFD with n-3 PUFA from marine or plant sources showed significantly improved vascular responses as compared with the MUFA-rich LFD (E(max), P < .05) and ob/ob reference mice consuming chow (E(max) and pEC(50), P < .05). In summary, long-term consumption of LFD with n-3 PUFAs improved blood

Health benefits of n-3 polyunsaturated fatty acids: eicosapentaenoic acid and docosahexaenoic acid.

PubMed

Siriwardhana, Nalin; Kalupahana, Nishan S; Moustaid-Moussa, Naima

2012-01-01

Marine-based fish and fish oil are the most popular and well-known sources of n-3 polyunsaturated fatty acids (PUFAs), namely, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These n-3 PUFAs are known to have variety of health benefits against cardiovascular diseases (CVDs) including well-established hypotriglyceridemic and anti-inflammatory effects. Also, various studies indicate promising antihypertensive, anticancer, antioxidant, antidepression, antiaging, and antiarthritis effects. Moreover, recent studies also indicate anti-inflammatory and insulin-sensitizing effects of these fatty acids in metabolic disorders. Classically, n-3 PUFAs mediate some of these effects by antagonizing n-6 PUFA (arachidonic acid)-induced proinflammatory prostaglandin E₂ (PGE₂) formation. Another well-known mechanism by which n-3 PUFAs impart their anti-inflammatory effects is via reduction of nuclear factor-κB activation. This transcription factor is a potent inducer of proinflammatory cytokine production, including interleukin 6 and tumor necrosis factor-α, both of which are decreased by EPA and DHA. Other evidence also demonstrates that n-3 PUFAs repress lipogenesis and increase resolvins and protectin generation, ultimately leading to reduced inflammation. Finally, beneficial effects of EPA and DHA in insulin resistance include their ability to increase secretion of adiponectin, an anti-inflammatory adipokine. In summary, n-3 PUFAs have multiple health benefits mediated at least in part by their anti-inflammatory actions; thus their consumption, especially from dietary sources, should be encouraged. Copyright © 2012 Elsevier Inc. All rights reserved.

Neuroprotection in rabbit retina with N-acetyl-aspartylglutamate and 2-phosphonyl-methyl pentanedioic acid

NASA Astrophysics Data System (ADS)

Hacker, Henry D.; Yourick, Debra L.; Koenig, Michael K.; Slusher, Barbara S.; Meyerhoff, James L.

1999-06-01

Retinal tissue is subject to ischemia from diabetic retinopathy and other conditions that affect the retinal vasculature such as lupus erythematosus and temporal arteritis. There is evidence in animal models of reversible ischemia that a therapeutic window exists during early recovery when agents that reduce glutamate activity at its receptor sites can rescue neurons from injury. To model ischemia, we used sodium cyanide (NaCN), to inhibit oxidative metabolism, and 2-deoxyglucose (2-DG) to inhibit glycolysis. Dissociated rabbit retina cells were studied to evaluate the potential neuroprotective effects of N-acetyl-aspartyl-glutamate (MAAG), which competes with glutamate as a low-potency agonist at the NMDA receptor complex. N-acetylated α-linked acidic dipeptidase (NAALADase; the NAAG-hydrolyzing enzyme) is responsible for the hydrolysis of NAAG into glutamate, a neurotransmitter and potent excitotoxin, and N-acetylaspartate. 2-Phosphonyl-methyl pentanedioic acid (PMPA) and β-linked NAAG (β-NAAG), inhibitors of NAALADase, were also tested, since inhibition of NAALADase could reduce synaptic glutamate and increase the concentration of NAAG. We found that metabolic inhibition with NaCN/2-DG for 1 hour caused 50% toxicity as assessed with the MTT assay. Co-treatment with NAAG resulted in dose-dependent protection of up to 55% (p<0.005). When the non-hydrolyzable, NAALADase inhibitor β-NAAG was employed dose-dependent protection of up to 37% was observed (p<0.001). PMPA also showed 48% protection (p<.05-.001) against these insults. These data suggest that NAAG may antagonize the effect of glutamate at the NMDA receptor complex in retina. Inhibition of NAALADase by PMPA and β-NAAG may increase the activity of endogenous NAAG.

Kinetics study on the degradation of a model naphthenic acid by ethylenediamine-N,N'-disuccinic acid-modified Fenton process.

PubMed

Zhang, Ying; Klamerth, Nikolaus; Messele, Selamawit Ashagre; Chelme-Ayala, Pamela; Gamal El-Din, Mohamed

2016-11-15

Naphthenic acids (NAs) are reported to be the main species responsible for the oil sands process-affected water (OSPW) toxicity. In this study, the degradation of cyclohexanoic acid (CHA) as a model compound for NAs by an ethylenediamine-N,N'-disuccinic acid (EDDS)-modified Fenton process was investigated at pH 8. Optimum dose for Fe-EDDS (EDDS:Fe=2:1) was 0.45mM, and 2.94mM for hydrogen peroxide (H2O2). The time profiles of the main species in the process were studied, including CHA, H2O2, Fe(II), total Fe, and Fe-EDDS (in the main form of Fe(III)EDDS). The second-order rate constant between EDDS and hydroxyl radical (OH) at pH 8 was obtained as 2.48±0.43×10(9)M(-1)s(-1). OH was proved to be the main species responsible for the CHA degradation, while superoxide radical (O2(-)) played a minor role. The consecutive addition of H2O2 and Fe-EDDS led to a higher removal of CHA compared to that achieved by adding the reagents at a time. The half-wave potential of Fe(III/II)EDDS was measured at pH 7-9. The EDDS-modified Fenton process is a promising alternative to degrade NAs. Copyright © 2016 Elsevier B.V. All rights reserved.

Simultaneous determination of ascorbic acid, dopamine and uric acid by a novel electrochemical sensor based on N2/Ar RF plasma assisted graphene nanosheets/graphene nanoribbons.

PubMed

Jothi, Lavanya; Neogi, Sudarsan; Jaganathan, Saravana Kumar; Nageswaran, Gomathi

2018-05-15

A novel nitrogen/argon (N 2 /Ar) radio frequency (RF) plasma functionalized graphene nanosheet/graphene nanoribbon (GS/GNR) hybrid material (N 2 /Ar/GS/GNR) was developed for simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA). Various nitrogen mites introduced into GS/GNR hybrid structure was evidenced by a detailed microscopic, spectroscopic and surface area analysis. Owing to the unique structure and properties originating from the enhanced surface area, nitrogen functional groups and defects introduced on both the basal and edges, N 2 /Ar/GS/GNR/GCE showed high electrocatalytic activity for the electrochemical oxidations of AA, DA, and UA with the respective lowest detection limits of 5.3, 2.5 and 5.7 nM and peak-to-peak separation potential (ΔE P ) (vs Ag/AgCl) in DPV of 220, 152 and 372 mV for AA/DA, DA/UA and AA/UA respectively. Moreover, the selectivity, stability, repeatability and excellent performance in real time application of the fabricated N 2 /Ar/GS/GNR/GCE electrode suggests that it can be considered as a potential electrode material for simultaneous detection of AA, DA, and UA. Copyright © 2018 Elsevier B.V. All rights reserved.

Microwave-assisted nitric acid treatment of sepiolite and functionalization with polyethylenimine applied to CO2 capture and CO2/N2 separation

NASA Astrophysics Data System (ADS)

Vilarrasa-García, E.; Cecilia, J. A.; Bastos-Neto, M.; Cavalcante, C. L.; Azevedo, D. C. S.; Rodríguez-Castellón, E.

2017-07-01

Sepiolite was treated in HNO3 solutions with the assistance of microwave radiation. This treatment caused the progressive depletion of Mg2+, the gradual degradation of the sepiolite structure and the formation of an amorphous silica phase, which contributes to a noticeable increase of the surface area. The use of microwaves during acid treatment, after few minutes, led to materials with similar SBET to those obtained after 48 h with conventional heating methods. The influence of mineralogical impurities, crystallinity and chemical composition in the reactivity of sepiolite to this treatment was also studied. The obtained materials were impregnated with polyethylenimine and assessed for CO2 capture and CO2/N2 selectivity at different temperatures. Experimental equilibrium data were fitted to Langmuir and Sips models. The adsorption data revealed that sepiolite can be an interesting adsorbent for CO2 capture, achieving a capacity of 1.70 mmol g-1 at 338 K and 1 bar, providing a high CO2/N2 selectivity (440 mol CO2/mol N2).

Dietary acid load and risk of type 2 diabetes: the E3N-EPIC cohort study.

PubMed

Fagherazzi, Guy; Vilier, Alice; Bonnet, Fabrice; Lajous, Martin; Balkau, Beverley; Boutron-Rualt, Marie-Christine; Clavel-Chapelon, Françoise

2014-02-01

The objective of this study was to evaluate the prospective relationship between dietary acid load, assessed with both the potential renal acid load (PRAL) and the net endogenous acid production (NEAP) scores, and type 2 diabetes risk. A total of 66,485 women from the E3N-EPIC cohort were followed for incident diabetes over 14 years. PRAL and NEAP scores were derived from nutrient intakes. HRs for type 2 diabetes risk across quartiles of the baseline PRAL and NEAP scores were estimated with multivariate Cox regression models. During follow-up, 1,372 cases of incident type 2 diabetes were validated. In the overall population, the highest PRAL quartile, reflecting a greater acid-forming potential, was associated with a significant increase in type 2 diabetes risk, compared with the first quartile (HR 1.56, 95% CI 1.29, 1.90). The association was stronger among women with BMI <25 kg/m2 (HR 1.96, 95% CI 1.43, 2.69) than in overweight women (HR 1.28, 95% CI 1.00, 1.64); statistically significant trends in risk across quartiles were observed in both groups (p trend < 0.0001 and p trend = 0.03, respectively). The NEAP score provided similar findings. We have demonstrated for the first time in a large prospective study that dietary acid load was positively associated with type 2 diabetes risk, independently of other known risk factors for diabetes. Our results need to be validated in other populations, and may lead to promotion of diets with a low acid load for the prevention of diabetes. Further research is required on the underlying mechanisms.

Dietary n-3 fatty acid restriction during gestation in rats: neuronal cell body and growth-cone fatty acids.

PubMed

Auestad, N; Innis, S M

2000-01-01

Growth cones are membrane-rich structures found at the distal end of growing axons and are the predecessors of the synaptic membranes of nerve endings. This study examined whether n-3 fatty acid restriction during gestation in rats alters the composition of growth cone and neuronal cell body membrane fatty acids in newborns. Female rats were fed a standard control diet containing soy oil (8% of fatty acids as 18:3n-3 by wt) or a semisynthetic n-3 fatty acid-deficient diet with safflower oil (0.3% of fatty acids as 18:3n-3 by wt) throughout normal pregnancy. Experiments were conducted on postnatal day 2 to minimize the potential for contamination from synaptic membranes and glial cells. Dietary n-3 fatty acid restriction resulted in lower docosahexaenoic acid (DHA) concentrations and a corresponding higher docosapentaenoic acid concentration in neuronal growth cones, but had no effects on neuronal cell body fatty acid concentrations. These studies suggest that accretion of DHA in growth cones, but not neuronal cell bodies, is affected by n-3 fatty acid restriction during gestation. Differences in other fatty acids or components between the semisynthetic and the standard diet, however, could have been involved in the effects on growth-cone DHA content. The results also provide evidence to suggest that the addition of new membrane fatty acids to neurons during development occurs along the shaft of the axon or at the growth cone, rather than originating at the cell body.

N-3 polyunsaturated fatty acid regulation of hepatic gene transcription

PubMed Central

Jump, Donald B.

2009-01-01

Purpose of review The liver plays a central role in whole body lipid metabolism and adapts rapidly to changes in dietary fat composition. This adaption involves changes in the expression of genes involved in glycolysis, de-novo lipogenesis, fatty acid elongation, desaturation and oxidation. This review brings together metabolic and molecular studies that help explain n-3 (omega-3) polyunsaturated fatty acid regulation of hepatic gene transcription. Recent findings Dietary n-3 polyunsaturated fatty acid regulates hepatic gene expression by targeting three major transcriptional regulatory networks: peroxisome proliferator-activated receptor α, sterol regulatory element binding protein-1 and the carbohydrate regulatory element binding protein/Max-like factor X heterodimer. 22 : 6,n-3, the most prominent n-3 polyunsaturated fatty acid in tissues, is a weak activator of peroxisome proliferator-activated receptor α. Hepatic metabolism of 22 : 6,n-3, however, generates 20 : 5,n-3, a strong peroxisome proliferator-activated receptor α activator. In contrast to peroxisome proliferator-activated receptor α, 22 : 6,n-3 is the most potent fatty acid regulator of hepatic sterol regulatory element binding protein-1. 22 : 6,n-3 suppresses sterol regulatory element binding protein-1 gene expression while enhancing degradation of nuclear sterol regulatory element binding protein-1 through 26S proteasome and Erk1/2-dependent mechanisms. Both n-3 and n-6 polyunsaturated fatty acid suppress carbohydrate regulatory element binding protein and Max-like factor X nuclear abundance and interfere with glucose-regulated hepatic metabolism. Summary These studies have revealed unique mechanisms by which specific polyunsaturated fatty acids control peroxisome proliferator activated receptor α, sterol regulatory element binding protein-1 and carbohydrate regulatory element binding protein/Max-like factor X function. As such, specific metabolic and signal transduction pathways contribute

Spectroscopic and electrochemical properties of group 12 acetates of di-2-pyridylketone thiophene-2-carboxylic acid hydrazone (dpktch-H) complexes. The structure of [Cd(η³-N,N,O-dpktch-H)₂].

PubMed

Bakir, Mohammed; Lawrence, Mark A W; McBean, Shameal

2015-07-05

The reaction between [dpktch] and [M(OAc)2] (M=group 12 metal atom) in refluxing CH3CN gave [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O (n=0 or 1). The infrared and (1)H NMR spectra are consistent with the coordination of [η(2)-O,O-OAc] and [η(3)-N,N,O-dpktch-H](-) and the proposed formulations. The electronic absorption spectra of [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O measured in non-aqueous solvents revealed a highly intense intra-ligand-charge transfer (ILCT) transition due to π-π∗ of dpk followed by dpk→thiophene charge transfer. The electronic transitions of [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O are solvent and concentration dependent. Spectrophotometric titrations of dmso solutions of [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O with benzoic acid revealed irreversible inter-conversion between [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O and it conjugate acid [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch)]·nH2O pointing to ligand exchange between the acetate and benzoate anions. When CH2Cl2 solutions of [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O were titrated with dmso, changes appeared pointing to solvolysis or ligand exchange reactions. Electrochemical measurements on dmso solutions of [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O divulged irreversible redox transformations consistent with electrochemical decomposition of [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O. The solid state structure of a single crystal of [Cd(η(3)-N,N,O-dpktch-H)2] obtained from a dmso solution of [Cd(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O confirmed the ligand scrambling of [M(η(2)-O,O-OAc)(η(3)-N,N,O-dpktch-H)]·nH2O. The extended structure of [Cd(η(3)-N,N,O-dpktch-H)2] revealed stacks of [Cd(η(3)-N,N,O-dpktch-H)2] locked via a network of hydrogen bonds. A significant amount of empty space (35.5%) was observed in the solid state structure of [Cd(η(3)-N,N,O-dpktch-H)2]. Copyright © 2015 Elsevier B.V. All rights reserved.

Three polymorphs of an inclusion compound of 2,2'-(disulfanediyl)dibenzoic acid and trimethylamine.

PubMed

Yang, Yunxia; Li, Lihua; Zhang, Li; Dong, Wenjing; Ding, Keying

2016-12-01

Polymorphism is the ability of a solid material to exist in more than one form or crystal structure and this is of interest in the fields of crystal engineering and solid-state chemistry. 2,2'-(Disulfanediyl)dibenzoic acid (also called 2,2'-dithiosalicylic acid, DTSA) is able to form different hydrogen bonds using its carboxyl groups. The central bridging S atoms allow the two terminal arene rings to rotate freely to generate various hydrogen-bonded linking modes. DTSA can act as a potential host molecule with suitable guest molecules to develop new inclusion compounds. We report here the crystal structures of three new polymorphs of the inclusion compound of DTSA and trimethylamine, namely trimethylazanium 2-[(2-carboxyphenyl)disulfanyl]benzoate 2,2'-(disulfanediyl)dibenzoic acid monosolvate, C 3 H 10 N + ·C 14 H 9 O 4 S 2 - ·C 14 H 10 O 4 S 2 , (1), tetrakis(trimethylazanium) bis{2-[(2-carboxyphenyl)disulfanyl]benzoate} 2,2'-(disulfanediyl)dibenzoate 2,2'-(disulfanediyl)dibenzoic acid monosolvate, 4C 3 H 10 N + ·2C 14 H 9 O 4 S 2 - ·C 14 H 8 O 4 S 2 2- ·C 14 H 10 O 4 S 2 , (2), and trimethylazanium 2-[(2-carboxyphenyl)disulfanyl]benzoate, C 3 H 10 N + ·C 14 H 9 O 4 S 2 - , (3). In the three polymorphs, DTSA utilizes its carboxyl groups to form conventional O-H...O hydrogen bonds to generate different host lattices. The central N atoms of the guest amine molecules accept H atoms from DTSA molecules to give the corresponding cations, which act as counter-ions to produce the stable crystal structures via N-H...O hydrogen bonding between the host acid and the guest molecule. It is noticeable that although these three compounds are composed of the same components, the final crystal structures are totally different due to the various configurations of the host acid, the number of guest molecules and the inducer (i.e. ancillary experimental acid).

Proton-transfer compounds with 4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (sulfamethazine): the structures and hydrogen bonding in the salts with 5-nitrosalicylic acid and picric acid.

PubMed

Smith, Graham; Wermuth, Urs D

2013-05-01

The structures of the anhydrous proton-transfer compounds of the sulfa drug sulfamethazine with 5-nitrosalicylic acid and picric acid, namely 2-(4-aminobenzenesulfonamido)-4,6-dimethylpyrimidinium 2-hydroxy-5-nitrobenzoate, C12H15N4O2S(+)·C7H4NO4(-), (I), and 2-(4-aminobenzenesulfonamido)-4,6-dimethylpyrimidinium 2,4,6-trinitrophenolate, C12H15N4O2S(+)·C6H2N3O7(-), (II), respectively, have been determined. In the asymmetric unit of (I), there are two independent but conformationally similar cation-anion heterodimer pairs which are formed through duplex intermolecular N(+)-H···O(carboxylate) and N-H···O(carboxylate) hydrogen-bond pairs, giving a cyclic motif [graph set R2(2)(8)]. These heterodimers form separate and different non-associated substructures through aniline N-H···O hydrogen bonds, one one-dimensional, involving carboxylate O-atom acceptors, the other two-dimensional, involving both carboxylate and hydroxy O-atom acceptors. The overall two-dimensional structure is stabilized by π-π interactions between the pyrimidinium ring and the 5-nitrosalicylate ring in both heterodimers [minimum ring-centroid separation = 3.4580 (8) Å]. For picrate (II), the cation-anion interaction involves a slightly asymmetric chelating N-H···O R2(1)(6) hydrogen-bonding association with the phenolate O atom, together with peripheral conjoint R1(2)(6) interactions between the same N-H groups and O atoms of the ortho-related nitro groups. An inter-unit amine N-H···O(sulfone) hydrogen bond gives one-dimensional chains which extend along a and inter-associate through π-π interactions between the pyrimidinium rings [centroid-centroid separation = 3.4752 (9) Å]. The two structures reported here now bring to a total of four the crystallographically characterized examples of proton-transfer salts of sulfamethazine with strong organic acids.

Psathyrella velutina Mushroom Lectin Exhibits High Affinity toward Sialoglycoproteins Possessing Terminal N-Acetylneuraminic Acid alpha 2,3-Linked to Penultimate Galactose Residues of Trisialyl N-Glycans. Comparison with other sialic acid-specific lectins.

PubMed

Ueda, Haruko; Matsumoto, Hanako; Takahashi, Noriko; Ogawa, Haruko

2002-07-12

A lectin from the fruiting body of the Psathyrella velutina mushroom (PVL) was found to bind specifically to N-acetylneuraminic acid, as well as to GlcNAc (Ueda, H., Kojima, K., Saitoh, T., and Ogawa, H. (1999) FEBS Lett. 448, 75-80). In this study, the glycan sequences that PVL recognizes with high affinity on sialoglycoproteins were revealed. Among sialic acid-specific lectins only PVL could reveal the sialylated N-acetyllactosamine structure of glycoproteins in blotting studies, based on the dual specificity. The affinity of PVL to fetuin was measured by surface plasmon resonance to be 10(7) m(-1), which is an order of magnitude higher than those of Sambucus nigra agglutinin and Maackia amurensis mitogen, whereas affinity to asialofetuin was approximately 0 and to asialo-agalactofetuin was 10(8) m(-1), suggesting that PVL exhibits remarkably high affinities toward glycoproteins possessing trisialo- or GlcNAc-exposed glycans. Transferrin was separated into fractions that correspond to the sialylation states on an immobilized PVL column. Transferrin-possessing trisialoglycans containing alpha2,3-linked N-acetylneuraminic acid on the beta1,4-linked GlcNAc branch bound to the PVL column and eluted with GlcNAc; those containing only alpha2,6-linked sialic acids were retarded, whereas other transferrin fractions passed through the column. These results indicate that PVL is a lectin with potential for separation and detection of sialoglycoproteins because of its dual specificity toward sialoglycans and GlcNAc exposed glycans.

Red Blood Cell Docosapentaenoic Acid (DPA n-3) is Inversely Associated with Triglycerides and C-reactive Protein (CRP) in Healthy Adults and Dose-Dependently Increases Following n-3 Fatty Acid Supplementation

PubMed Central

Skulas-Ray, Ann C.; Flock, Michael R.; Richter, Chesney K.; Harris, William S.; West, Sheila G.; Kris-Etherton, Penny M.

2015-01-01

The role of the long-chain omega-3 (n-3) fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in lipid metabolism and inflammation has been extensively studied; however, little is known about the relationship between docosapentaenoic acid (DPA, 22:5 n-3) and inflammation and triglycerides (TG). We evaluated whether n-3 DPA content of red blood cells (RBC) was associated with markers of inflammation (interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and C-reactive protein (CRP) and fasting TG prior to n-3 supplementation in two studies (Study 1: n = 115, aged 20–44 years, body mass index (BMI) 20–30 kg/m2, TG = 34–176 mg/dL; Study 2: n = 28, aged 22–65 years, BMI 24–37 kg/m2, TG = 141–339 mg/dL). We also characterized the dose-response effects of n-3 fatty acid supplementation on RBC n-3 DPA after five months of supplementation with fish oil (Study 1: 0, 300, 600, 900, and 1800 mg/day EPA + DHA) and eight weeks of prescription n-3 ethyl esters (Study 2: 0, 850, and 3400 mg/day EPA + DHA). In Study 1, RBC n-3 DPA was inversely correlated with CRP (R2 = 36%, p < 0.001) and with fasting TG (r = −0.30, p = 0.001). The latter finding was replicated in Study 2 (r = −0.33, p = 0.04). In both studies, n-3 supplementation significantly increased RBC n-3 DPA dose-dependently. Relative increases were greater for Study 1, with increases of 29%–61% vs. 14%–26% for Study 2. The associations between RBC n-3 DPA, CRP, and fasting TG may have important implications for the prevention of atherosclerosis and chronic inflammatory diseases and warrant further study. PMID:26247967

Dietary (n-6 : n-3) Fatty Acids Alter Plasma and Tissue Fatty Acid Composition in Pregnant Sprague Dawley Rats

PubMed Central

Kassem, Amira Abdulbari; Abu Bakar, Md Zuki; Yong Meng, Goh; Mustapha, Noordin Mohamed

2012-01-01

The objective of this paper is to study the effects of varying dietary levels of n-6 : n-3 fatty acid ratio on plasma and tissue fatty acid composition in rat. The treatment groups included control rats fed chow diet only, rats fed 50% soybean oil (SBO): 50% cod liver oil (CLO) (1 : 1), 84% SBO: 16% CLO (6 : 1), 96% SBO: 4% CLO (30 : 1). Blood samples were taken at day 15 of pregnancy, and the plasma and tissue were analyzed for fatty acid profile. The n-3 PUFA in plasma of Diet 1 : 1 group was significantly higher than the other diet groups, while the total n-6 PUFA in plasma was significantly higher in Diet 30 : 1 group as compared to the control and Diet 1 : 1 groups. The Diet 1 : 1 group showed significantly greater percentages of total n-3 PUFA and docosahexaenoic acid in adipose and liver tissue, and this clearly reflected the contribution of n-3 fatty acids from CLO. The total n-6 PUFA, linoleic acid, and arachidonic acid were significantly difference in Diet 30 : 1 as compared to Diet 1 : 1 and control group. These results demonstrated that the dietary ratio of n-6 : n-3 fatty acid ratio significantly affected plasma and tissue fatty acids profile in pregnant rat. PMID:22489205

Installing amino acids and peptides on N-heterocycles under visible-light assistance

PubMed Central

Jin, Yunhe; Jiang, Min; Wang, Hui; Fu, Hua

2016-01-01

Readily available natural α-amino acids are one of nature’s most attractive and versatile building blocks in synthesis of natural products and biomolecules. Peptides and N-heterocycles exhibit various biological and pharmaceutical functions. Conjugation of amino acids or peptides with N-heterocycles provides boundless potentiality for screening and discovery of diverse biologically active molecules. However, it is a great challenge to install amino acids or peptides on N-heterocycles through formation of carbon-carbon bonds under mild conditions. In this article, eighteen N-protected α-amino acids and three peptides were well assembled on phenanthridine derivatives via couplings of N-protected α-amino acid and peptide active esters with substituted 2-isocyanobiphenyls at room temperature under visible-light assistance. Furthermore, N-Boc-proline residue was successfully conjugated with oxindole derivatives using similar procedures. The simple protocol, mild reaction conditions, fast reaction, and high efficiency of this method make it an important strategy for synthesis of diverse molecules containing amino acid and peptide fragments. PMID:26830014

Atypical cleavage of protonated N-fatty acyl amino acids derived from aspartic acid evidenced by sequential MS3 experiments.

PubMed

Boukerche, Toufik Taalibi; Alves, Sandra; Le Faouder, Pauline; Warnet, Anna; Bertrand-Michel, Justine; Bouchekara, Mohamed; Belbachir, Mohammed; Tabet, Jean-Claude

2016-12-01

Lipidomics calls for information on detected lipids and conjugates whose structural elucidation by mass spectrometry requires to rationalization of their gas phase dissociations toward collision-induced dissociation (CID) processes. This study focused on activated dissociations of two lipoamino acid (LAA) systems composed of N-palmitoyl acyl coupled with aspartic and glutamic acid mono ethyl esters (as LAA (*D) and LAA (*E) ). Although in MS/MS, their CID spectra show similar trends, e.g., release of water and ethanol, the [(LAA (*D/*E) +H)-C 2 H 5 OH] + product ions dissociate via distinct pathways in sequential MS 3 experiments. The formation of all the product ions is rationalized by charge-promoted cleavages often involving stepwise processes with ion isomerization into ion-dipole prior to dissociation. The latter explains the maleic anhydride or ketene neutral losses from N-palmitoyl acyl aspartate and glutamate anhydride fragment ions, respectively. Consequently, protonated palmitoyl acid amide is generated from LAA (*D), whereas LAA (*E) leads to the [*E+H-H 2 O] + anhydride. The former releases ammonia to provide acylium, which gives the C n H (2n-1) and C n H (2n-3) carbenium series. This should offer structural information, e.g., to locate either unsaturation(s) or alkyl group branching present on the various fatty acyl moieties of lipo-aspartic acid in further studies based on MS n experiments.

Collision-induced fragmentation of negative ions from N-linked glycans derivatized with 2-aminobenzoic acid.

PubMed

Harvey, David J

2005-05-01

N-Linked glycans from bovine ribonuclease B, chicken ovalbumin, bovine fetuin, porcine thyroglobulin and human alpha(1)-acid glycoprotein were derivatized with 2-aminobenzoic acid by reductive amination and their tandem mass spectra were recorded by negative ion electrospray ionization with a quadrupole time-of-flight mass spectrometer. Derivatives were also prepared from 2-amino-5-methyl- and 2-amino-4,5-dimethoxybenzoic acid in order to confirm the identity of fragment ions containing the reducing terminus. Major fragments from the [M - H](-) ions from the neutral glycans retained the derivative (Y-type cleavages) and provided information on sequence and branching. Other major fragments were products of A-type cross-ring cleavages giving information on antenna structure. Singly doubly and triply charged ions were formed from sialylated glycans. They produced major fragments by loss of sialic acid and a series of singly charged ions that were similar to those from the neutral analogues. Doubly charge ions were also produced by the neutral glycans and were fragmented to form product ions with one and two charges. Again, the fragment ions with a single charge were similar to those from the singly charged parents, but branching information was less obvious because of the occurrence of more abundant ions produced by multiple cleavages. Detection limits were around 200 fmol (3 : 1 signal-to-noise ratio). Copyright 2005 John Wiley & Sons, Ltd.

Primary amino acid derivatives: substitution of the 4'-N'-benzylamide site in (R)-N'-benzyl 2-amino-3-methylbutanamide, (R)-N'-benzyl 2-amino-3,3-dimethylbutanamide, and (R)-N'-benzyl 2-amino-3-methoxypropionamide provides potent anticonvulsants with pain-attenuating properties.

PubMed

King, Amber M; Salomé, Christophe; Salomé-Grosjean, Elise; De Ryck, Marc; Kaminski, Rafal; Valade, Anne; Stables, James P; Kohn, Harold

2011-10-13

Recently, we reported that select N'-benzyl 2-substituted 2-amino acetamides (primary amino acid derivatives (PAADs)) exhibited pronounced activities in established whole animal anticonvulsant (i.e., maximal electroshock seizure (MES)) and neuropathic pain (i.e., formalin) models. The anticonvulsant activities of C(2)-hydrocarbon N'-benzyl 2-amino acetamides (MES ED(50) = 13-21 mg/kg) exceeded those of phenobarbital (ED(50) = 22 mg/kg). Two additional studies defining the structure-activity relationship of PAADs are presented in this issue of the journal. In this study, we demonstrated that the anticonvulsant activities of (R)-N'-benzyl 2-amino-3-methylbutanamide and (R)-N'-benzyl 2-amino-3,3-dimethylbutanamide were sensitive to substituents at the 4'-N'-benzylamide site; electron-withdrawing groups retained activity, electron-donating groups led to a loss of activity, and incorporating either a 3-fluorobenzyloxy or 3-fluorophenoxymethyl group using a rationally designed multiple ligand approach improved activity. Additionally, we showed that substituents at the 4'-N'-benzylamide site of (R)-N'-benzyl 2-amino-3-methoxypropionamide also improved anticonvulsant activity, with the 3-fluorophenoxymethyl group providing the largest (∼4-fold) increase in activity (ED(50) = 8.9 mg/kg), a value that surpassed phenytoin (ED(50) = 9.5 mg/kg). Collectively, the pharmacological findings provided new information that C(2)-hydrocarbon PAADs represent a novel class of anticonvulsants.

REACTIONS OF MERCAPTANS. I. FORMATION OF 2-METHYL-2-THIAZOLINE-4- CARBOXYLIC ACID FROM N-ACETYLCYSTEINE. II. A SPECTROPHOTOMETRIC METHOD FOR STUDY OF THE REACTION OF RADIATION-PROTECTIVE MERCAPTANS WITH ARYL DISULFIDES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, H.A. Jr.

1962-08-01

I. Methyl 2-methyl-2-thiazoline-4-carboxylate was synthesized and converted to the corresponding acid. The behavior of the carboxythiazoline in various concentrations of mineral acids was studied spectrophotometrically. The cyclization of N-acetylcysteine to form a thiazoline-ring compound in concentrated mineral acids was also studied by this means. N-Acetylcysteine in concentrated mineral acid solutions yielded 2-methyl-2-thiazoline-4-carboxylic acid, which also was obtained by controlied hydrolysis of the corresponding methyl ester. Hydrolysis of methyl 2-methyl2-thiazoline-4-carboxylate, pK 3.05, in 0.1M sodium hydroxide yielded the corresponding carboxythiazoline in solution, pK 2.20 and 4.95. The carboxythiazoline was hydrolyzed very slowly in 7M hydrochloric acid, but the velocity of reactionmore » increased with decreasing acid concentration to a maximum at about pH 1.7; the products were N- and Sacetylcysteine, as well as cysteine and acetic acid. At acid concentrations below 0.2M, the last two products were formed slowly, and a pseudo-equilibrium could be established between thiazolinium ion, N-, and S-acetylcysteine. Equilibrium constants were determined. II. 4,4'-Dithiobis (benzenesulfonic acid) (I) and 4,4'-dithiobis(1-naphthalenesulfonic acid) (II) were synthesized from sulfanilic and naphthionic acids, respectively. The absorption spectra of I and II and of the corresponding mercaptans were determined. The thiol-disuifide interchange reactions were studied by spectrophotometric means for the reactions of cysteine with I and with II, and the equilibrium constants were determined. The systems had spectra very similar to those of the respective mixed disuifides with cysteine, and it was not possible to determine the concentrations from absorbancy measurements. On the other hand, the mercaptide ions had spectra different from the other species, with maxima at 285 and 348 m mu , respectively, and the concentrations of the corresponding mercaptans could

Unexpected Hydrolytic Instability of N-Acylated Amino Acid Amides and Peptides

PubMed Central

2015-01-01

Remote amide bonds in simple N-acyl amino acid amide or peptide derivatives 1 can be surprisingly unstable hydrolytically, affording, in solution, variable amounts of 3 under mild acidic conditions, such as trifluoroacetic acid/water mixtures at room temperature. This observation has important implications for the synthesis of this class of compounds, which includes N-terminal-acylated peptides. We describe the factors contributing to this instability and how to predict and control it. The instability is a function of the remote acyl group, R2CO, four bonds away from the site of hydrolysis. Electron-rich acyl R2 groups accelerate this reaction. In the case of acyl groups derived from substituted aromatic carboxylic acids, the acceleration is predictable from the substituent’s Hammett σ value. N-Acyl dipeptides are also hydrolyzed under typical cleavage conditions. This suggests that unwanted peptide truncation may occur during synthesis or prolonged standing in solution when dipeptides or longer peptides are acylated on the N-terminus with electron-rich aromatic groups. When amide hydrolysis is an undesired secondary reaction, as can be the case in the trifluoroacetic acid-catalyzed cleavage of amino acid amide or peptide derivatives 1 from solid-phase resins, conditions are provided to minimize that hydrolysis. PMID:24617596

N-Substituted carbazolyloxyacetic acids modulate Alzheimer associated gamma-secretase.

PubMed

Narlawar, Rajeshwar; Pérez Revuelta, Blanca I; Baumann, Karlheinz; Schubenel, Robert; Haass, Christian; Steiner, Harald; Schmidt, Boris

2007-01-01

N-Sulfonylated and N-alkylated carbazolyloxyacetic acids were investigated for the inhibition and modulation of the Alzheimer's disease associated gamma-secretase. The introduction of a lipophilic substituent, which may vary from arylsulfone to alkyl, turned 2-carbazolyloxyacetic acids into potent gamma-secretase modulators. This resulted in the selective reduction of Abeta(42) and an increase of the less aggregatory Abeta(38) fragment by several compounds (e.g., 7d and 8c). Introduction of an electron donating group at position 6 and 8 of N-substituted carbazolyloxyacetic acids either decreased the activity or inversed modulation. The most active compounds displayed activity on amyloid precursor protein (APP) overexpressing cell lines in the low micromolar range and little or no effect on the gamma-secretase cleavage at the epsilon-site.

n-3 fatty acids and cardiovascular outcomes in patients with dysglycemia.

PubMed

Bosch, Jackie; Gerstein, Hertzel C; Dagenais, Gilles R; Díaz, Rafael; Dyal, Leanne; Jung, Hyejung; Maggiono, Aldo P; Probstfield, Jeffrey; Ramachandran, Ambady; Riddle, Matthew C; Rydén, Lars E; Yusuf, Salim

2012-07-26

The use of n-3 fatty acids may prevent cardiovascular events in patients with recent myocardial infarction or heart failure. Their effects in patients with (or at risk for) type 2 diabetes mellitus are unknown. In this double-blind study with a 2-by-2 factorial design, we randomly assigned 12,536 patients who were at high risk for cardiovascular events and had impaired fasting glucose, impaired glucose tolerance, or diabetes to receive a 1-g capsule containing at least 900 mg (90% or more) of ethyl esters of n-3 fatty acids or placebo daily and to receive either insulin glargine or standard care. The primary outcome was death from cardiovascular causes. The results of the comparison between n-3 fatty acids and placebo are reported here. During a median follow up of 6.2 years, the incidence of the primary outcome was not significantly decreased among patients receiving n-3 fatty acids, as compared with those receiving placebo (574 patients [9.1%] vs. 581 patients [9.3%]; hazard ratio, 0.98; 95% confidence interval [CI], 0.87 to 1.10; P=0.72). The use of n-3 fatty acids also had no significant effect on the rates of major vascular events (1034 patients [16.5%] vs. 1017 patients [16.3%]; hazard ratio, 1.01; 95% CI, 0.93 to 1.10; P=0.81), death from any cause (951 [15.1%] vs. 964 [15.4%]; hazard ratio, 0.98; 95% CI, 0.89 to 1.07; P=0.63), or death from arrhythmia (288 [4.6%] vs. 259 [4.1%]; hazard ratio, 1.10; 95% CI, 0.93 to 1.30; P=0.26). Triglyceride levels were reduced by 14.5 mg per deciliter (0.16 mmol per liter) more among patients receiving n-3 fatty acids than among those receiving placebo (P<0.001), without a significant effect on other lipids. Adverse effects were similar in the two groups. Daily supplementation with 1 g of n-3 fatty acids did not reduce the rate of cardiovascular events in patients at high risk for cardiovascular events. (Funded by Sanofi; ORIGIN ClinicalTrials.gov number, NCT00069784.).

Gas-phase Conformational Analysis of (R,R)-Tartaric Acid, its Diamide, N,N,N',N'- Tetramethyldiamide and Model Compounds

NASA Astrophysics Data System (ADS)

Hoffmann, Marcin; Szarecka, Agnieszka; Rychlewski, Jacek

A review over most recent ab initio studies carried out at both RHF and MP2 levels on (R,R)-tartaric acid (TA), its diamide (DA), tetramethyldiamide (TMDA) and on three prototypic model systems (each of them constitutes a half of the respective parental molecule), i.e. 2-hydroxyacetic acid (HA), 2-hydroxyacetamide (HD) and 2-hydroxy-N,N-dimethylacetamide (HMD) is presented. (R,R)-tartaric acid and the derivatives have been completely optimized at RHF/6-31G* level and subsequently single-point energies of all conformers have been calculated with the use of second order perturbation theory according to the scheme: MP2/6-31G*//RHF/6-31G*. In the complete optimization of the model molecules at RHF level we have employed relatively large basis sets, augmented with polarisation and diffuse functions, namely 3-21G, 6-31G*, 6-31++G** and 6-311++G**. Electronic correlation has been included with the largest basis set used in this study, i.e. MP2/6-311++G**//RHF/6-311++G** single-point energy calculations have been performed. General confomational preferences of tartaric acid derivatives have been analysed as well as an attempt has been made to define main factors affecting the conformational behaviour of these molecules in the isolated state, in particular, the role and stability of intramolecular hydrogen bonding. In the case of the model compounds, our study principally concerned the conformational preferences and hydrogen bonding structure within the [alpha]-hydroxy-X moiety, where X=COOH, CONH2, CON(CH3)2.

Supplementation with n-3, n-6, n-9 fatty acids in an insulin-resistance animal model: does it improve VLDL quality?

PubMed

Lucero, D; Olano, C; Bursztyn, M; Morales, C; Stranges, A; Friedman, S; Macri, E V; Schreier, L; Zago, V

2017-05-24

Insulin-resistance (IR), of increased cardiovascular risk, is characterized by the production of altered VLDL with greater atherogenicity. Dietary fatty acids influence the type of circulating VLDL. But, it is not clear how dietary fatty acids impact VLDL characteristics in IR. to evaluate the effects of n-3, n-6 and n-9 fatty acid supplementation on preventing atherogenic alterations in VLDL, in a diet-induced IR rat model. Male Wistar rats (180-200 g) were fed: standard diet (control, n = 8) and a sucrose rich diet (30% sucrose in water/12 weeks, SRD; n = 24). Simultaneously, SRD was subdivided into SRD-C (standard diet), and three other groups supplemented (15% w/w) with: fish oil (SRD-n3), sunflower oil (SRD-n6) and high oleic sunflower oil (SRD-n9). Lipid profile, free fatty acids, glucose, and insulin were measured. Isolated VLDL (d < 1.006 g ml -1 ) was characterized by chemical composition and size (size exclusion-HPLC). In comparison with SRD-C: SRD-n3 showed an improved lipoprotein profile (p < 0.01), with lower levels of insulin and HOMA-IR (p < 0.05). SRD-n6 showed increased levels of HDL-cholesterol and lower insulin levels. SRD-n9 did not exhibit differences in lipid and IR profile, and even favored weight gain and visceral fat. Only SRD-n3 prevented the alterations in VLDL-TG% (54.2 ± 4.4% vs. 68.6 ± 8.2, p < 0.05) and showed lower large VLDL-% (22.5[19.7-35.6] vs. 49.1[15.5-82.0], p < 0.05), while SRD-n6 and SRD-n9 did not show effects. In IR, while n-3 PUFA showed expected favorable effects, supplementation with n-6 PUFA and n-9 MUFA did not prevent atherogenic alterations of VLDL. Thus, the recommendations of supplementation with these fatty acids in general diet should be revised.

The existence and gas phase acidity of the HAlnF3n+1 superacids (n = 1-4)

NASA Astrophysics Data System (ADS)

Czapla, Marcin; Skurski, Piotr

2015-06-01

Novel strong superacids are proposed and investigated on the basis of ab initio calculations. The gas phase acidity of the HAlF4, HAl2F7, and HAl3F10 systems evaluated by the estimation of the Gibbs free energies of their deprotonation reactions were found significant and comparable to the corresponding value characterizing the HTaF6, whereas the strength of the HAl4F13 acid was predicted to exceed that of the HSbF6 acid (the strongest liquid superacid recognized). The deprotonation energies of the HAlnF3n+1 acids (n = 1-4) turned out to be closely related to the electronic stabilities of their corresponding (AlnF3n+1)- anions.

Effects of dietary saturated and n-6 polyunsaturated fatty acids on the incorporation of long-chain n-3 polyunsaturated fatty acids into blood lipids.

PubMed

Dias, C B; Wood, L G; Garg, M L

2016-07-01

Omega-3 polyunsaturated fatty acids (n-3PUFA) are better absorbed when they are combined with high-fat meals. However, the role of different dietary fats in modulating the incorporation of n-3PUFA in blood lipids in humans has not been previously explored. Omega-6 polyunsaturated fatty acids (n-6PUFA) are known to compete with n-3PUFA in the metabolic pathways and for the incorporation into phospholipids, whereas saturated fats (SFA) may enhance n-3PUFA incorporation into tissues. In a randomized parallel-design trial, we aimed to investigate the long-term effects of n-3PUFA supplementation in subjects consuming a diet enriched with either SFA or n-6PUFA on fatty acid incorporation into plasma and erythrocytes and on blood lipid profiles (total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides). Dietary supplementation with n-3PUFA co-administered with SFA for 6 weeks resulted in a significant rise in total cholesterol (0.46±0.60 mmol/L; P=0.020) and LDL-C (0.48±0.48 mmol/L; P=0.011) in comparison with combination with n-6PUFA. The diet enriched with SFA also induced a greater increase in eicosapentaenoic acid (2.07±0.79 vs 1.15±0.53; P=0.004), a smaller decrease in docosapentaenoic acid (-0.12±0.23 vs -0.30±0.20; P=0.034) and a similar increase in docosahexaenoic acid (3.85±1.14 vs 3.10±1.07; P=0.128) percentage in plasma compared with the diet enriched with n-6PUFA. A similar effect was seen in erythrocytes. N-3PUFA supplementation resulted in similar changes in HDL-C and triglyceride levels. The results suggest that dietary substitution of SFA with n-6PUFA, despite maintaining low levels of circulating cholesterol, hinders n-3PUFA incorporation into plasma and tissue lipids.

[Effect of humic acids on migration and transformation of NH4(+) -N in saturated aquifer].

PubMed

Meng, Qing-Jun; Zhang, Yan; Feng, Qi-Yan; Zhang, Shuang-Sheng

2011-11-01

Isothermal adsorption experiment was used to study the adsorbing process of NH4(+) -N in quartz sands under the conditions with and without humic acid; the Langmuir and Freundlich equations were used to fit the absorption result and the maximum adsorption capacity of NH4(+) -N by quarts sands was calculated. Through the soil column experiments, the concentration of NH4(+) -N, NO3(-) -N and NO2(-) -N in effluent water in the tested soil column was investigated, and the effect of humic acid on migration and transformation of NH4(+) -N in saturated aquifer was analyzed, and Pseudo-second-order Kinetics Equation and Two-step Adsorption Kinetics Rate Equation were applied to fit the kinetic processes. The results showed that both Langmuir and Freundlich models can well describe the isothermal adsorption process of NH4(+) -N on the surface of quartz sands, which means that NH4(+) -N adsorbed by the quartz sand was mainly in the form of monolayer adsorption. The humic acid could increase the adsorption capacity of NH4(+) -N on quartz sand, and the saturated adsorption capacity was 0.354 mg x g(-1) under the condition with humic acid and 0.205 mg x g(-1) with the absence of humic acid. The experiment indicated that humic acid increased the adsorption capacity of NH4(+) -N on the surface of quartz sand by increasing adsorption space in the initial stage. After saturation, humic acid influenced the migration and transformation of NH4(+) -N to NO3(-) -N and NO2(-) -N probably through providing carbon source and energy for microorganisms such as nitrifying bacteria and then resulting in lower NH4(+) -N concentration in effluent water. Both Pseudo-second-order Kinetics Equation and Two-step Adsorption Kinetics Rate Equations can well describe the process of NH4(+) -N adsorption kinetics on quartz sand (R2 = 0.997 7 and R2 = 0.998 1 with humic acid; R2 = 0.992 3 and R2 = 0.994 4 without humic acid), indicating that this process was chemical adsorption. By comparing the

Halogeno-substituted 2-aminobenzoic acid derivatives for negative ion fragmentation studies of N-linked carbohydrates.

PubMed

Harvey, David J

2005-01-01

Negative ion electrospray mass spectra of high-mannose N-linked glycans derivatised with 2-aminobenzoic acids and ionised from solutions containing ammonium hydroxide gave prominent [M-H](-) ions accompanied by weaker [M-2H](2-) ions. Fragmentation of both types of ions gave prominent singly charged glycosidic cleavage ions containing the derivatised reducing terminus and ions from the non-reducing terminus that appeared to be products of cross-ring cleavages. Differentiation of these two groups of ions was conveniently achieved in a single spectrum by use of chloro- or bromo-substituted benzoic acids in order to label ions containing the derivative with an atom with a distinctive isotope pattern. Fragmentation of the doubly charged ions gave more abundant fragments, both singly and doubly charged, than did fragmentation of the singly charged ions, but information of chain branching was masked by the appearance of prominent ions produced by internal cleavages. Copyright (c) 2005 John Wiley & Sons, Ltd.

4-Aza-1-azoniabicyclo­[2.2.2]octa­ne–2-amino­benzoate–2-amino­benzoic acid (1/1/1)

PubMed Central

Arman, Hadi D.; Kaulgud, Trupta; Tiekink, Edward R. T.

2011-01-01

A 4-aza-1-azoniabicyclo­[2.2.2]octane cation, a 2-amino­benzoate anion and a neutral 2-amino­benzoic acid mol­ecule comprise the asymmetric unit of the title compound, C6H13N2 +·C7H6NO2 −·C7H7NO2. An intra­molecular N—H⋯O hydrogen bond occurs in the anion and in the neutral 2-amino­benzoic acid mol­ecule. The cation provides a charge-assisted N—H⋯O hydrogen bond to the anion, and the 2-amino­benzoic acid mol­ecule forms an O—H⋯N hydrogen bond to the unprotonated amino N atom in the cation. In this way, a three-component aggregate is formed. These are connected into a three-dimensional network by amino–carboxyl­ate N—H⋯O hydrogen bonds. N—H⋯N hydrogen bonds are also observed. PMID:22219964

Thermodynamic Studies to Support Actinide/Lanthanide Separations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, Linfeng

2016-09-04

Thermodynamic data on the complexation of Np(V) with HEDTA in a wide pH region were re-modeled by including a dimeric complex species, (NpO 2) 2(OH) 2L 2 6- where L 3- stands for the fully deprotonated HEDTA ligand and better fits were achieved for the spectrophotometric data. The presence of the dimeric complex species in high pH region was verified for the first time by the EXAFS experiments at Stanford Synchrotron Radiation Laboratory (SSRL).

Glycine N-acyltransferase-like 3 is responsible for long-chain N-acylglycine formation in N18TG2 cells[S

PubMed Central

Jeffries, Kristen A.; Dempsey, Daniel R.; Farrell, Emma K.; Anderson, Ryan L.; Garbade, Gabrielle J.; Gurina, Tatyana S.; Gruhonjic, Imran; Gunderson, Carly A.

2016-01-01

Long-chain fatty acid amides are signaling lipids found in mammals and other organisms; however, details of the metabolic pathways for the N-acylglycines and primary fatty acid amides (PFAMs) have remained elusive. Heavy-labeled precursor and subtraction lipidomic experiments in mouse neuroblastoma N18TG2 cells, a model cell line for the study of fatty acid amide metabolism, establish the biosynthetic pathways for the N-acylglycines and the PFAMs. We provide evidence that the N-acylglycines are formed by a long-chain specific glycine-conjugating enzyme, glycine N-acyltransferase-like 3 (GLYATL3). siRNA knockdown of GLYATL3 in the N18TG2 cells resulted in a decrease in the levels of the N-acylglycines and the PFAMs. This is the first report of an enzyme responsible for long-chain N-acylglycine production in cellula. The production of the PFAMs in N18TG2 cells was reported to occur by the oxidative cleavage of the N-acylglycines, as catalyzed by peptidylglycine α-amidating monooxygenase (PAM). siRNA knockdown of PAM resulted in an accumulation of [13C18]N-oleoylglycine and decreased levels of [13C18]oleamide when the N18TG2 cells were grown in the presence of [13C18]oleic acid. The addition of [1-13C]palmitate to the N18TG2 cell growth media led to the production of a family of [1-13C]palmitoylated fatty acid amides, consistent with the biosynthetic pathways detailed herein. PMID:27016726

Glutamic Acid as a Precursor to N-Terminal Pyroglutamic Acid in Mouse Plasmacytoma Protein

PubMed Central

Twardzik, Daniel R.; Peterkofsky, Alan

1972-01-01

Cell suspensions derived from a mouse plasmacytoma (RPC-20) that secretes an immunoglobulin light chain containing N-terminal pyroglutamic acid can synthesize protein in vitro. Chromatographic examination of an enzymatic digest of protein labeled with glutamic acid shows only labeled glutamic acid and pyroglutamic acid; hydrolysis of protein from cells labeled with glutamine, however, yields substantial amounts of glutamic acid in addition to glutamine and pyroglutamic acid. The absence of glutamine synthetase and presence of glutaminase in plasmacytoma homogenates is consistent with these findings. These data indicate that N-terminal pyroglutamic acid can be derived from glutamic acid without prior conversion of glutamic acid to glutamine. Since free or bound forms of glutamine cyclize nonezymatically to pyroglutamate with ease, while glutamic acid does not, the data suggest that N-terminal pyroglutamic acid formation from glutamic acid is enzymatic rather than spontaneous. Images PMID:4400295

Polyunsaturated fatty acids balance affects platelet NOX2 activity in patients with liver cirrhosis.

PubMed

Basili, Stefania; Raparelli, Valeria; Napoleone, Laura; Del Ben, Maria; Merli, Manuela; Riggio, Oliviero; Nocella, Cristina; Carnevale, Roberto; Pignatelli, Pasquale; Violi, Francesco

2014-07-01

NADPH-oxidase-2 up-regulation has been suggested in liver damage perpetuation via an oxidative stress-mediated mechanism. n-6/n-3 polyunsaturated fatty acids ratio derangement has been reported in liver disease. To explore polyunsaturated fatty acids balance and its interplay with platelet oxidative stress in liver cirrhosis. A cross-sectional study in 51 cirrhotic patients and sex- and age-matched controls was performed. Serum polyunsaturated fatty acids and oxidative stress markers (urinary isoprostanes and serum soluble NADPH-oxidase-2-derived peptide) were measured. The effect on platelet oxidative stress of n-6/n-3 polyunsaturated fatty acids ratio in vitro and in vivo (1-week supplementation with 3g/daily n-3-polyunsaturated fatty acids) was tested. Compared to controls, cirrhotic patients had significantly higher n-6/n-3 polyunsaturated fatty acids ratio. n-6/n-3 polyunsaturated fatty acids ratio correlated significantly with disease severity and oxidative stress markers. In vitro experiments showed that in Child-Pugh C patients' platelets incubation with low n-6/n-3 polyunsaturated fatty acids ratio resulted in dose-dependent decrease of radical oxigen species (-39%), isoprostanes (-25%) and NADPH-oxidase-2 regulation (-51%). n-3 polyunsaturated fatty acids supplemented patients showed significant oxidative stress indexes reduction. In cirrhosis, n-6/n-3 polyunsaturated fatty acids imbalance up-regulates platelet NADPH-oxidase-2 with ensuing oxidative stress. Further study to evaluate if n-3 supplementation may reduce disease progression is warranted. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Simple and Robust N-Glycan Analysis Based on Improved 2-Aminobenzoic Acid Labeling for Recombinant Therapeutic Glycoproteins.

PubMed

Jeong, Yeong Ran; Kim, Sun Young; Park, Young Sam; Lee, Gyun Min

2018-03-21

N-glycans of therapeutic glycoproteins are critical quality attributes that should be monitored throughout all stages of biopharmaceutical development. To reduce both the time for sample preparation and the variations in analytical results, we have developed an N-glycan analysis method that includes improved 2-aminobenzoic acid (2-AA) labeling to easily remove deglycosylated proteins. Using this analytical method, 15 major 2-AA-labeled N-glycans of Enbrel ® were separated into single peaks in hydrophilic interaction chromatography mode and therefore could be quantitated. 2-AA-labeled N-glycans were also highly compatible with in-line quadrupole time-of-flight mass spectrometry (MS) for structural identification. The structures of 15 major and 18 minor N-glycans were identified from their mass values determined by quadrupole time-of-flight MS. Furthermore, the structures of 14 major N-glycans were confirmed by interpreting the MS/MS data of each N-glycan. This analytical method was also successfully applied to neutral N-glycans of Humira ® and highly sialylated N-glycans of NESP ® . Furthermore, the analysis data of Enbrel ® that were accumulated for 2.5 years demonstrated the high-level consistency of this analytical method. Taken together, the results show that a wide repertoire of N-glycans of therapeutic glycoproteins can be analyzed with high efficiency and consistency using the improved 2-AA labeling-based N-glycan analysis method. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Molecular Structure of WlbB, a Bacterial N-Acetyltransferase Involved in the Biosynthesis of 2,3-Diacetamido-2,3-dideoxy-d-mannuronic Acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thoden, James B.; Holden, Hazel M.

2010-09-08

The pathogenic bacteria Pseudomonas aeruginosa and Bordetella pertussis contain in their outer membranes the rare sugar 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid. Five enzymes are required for the biosynthesis of this sugar starting from UDP-N-acetylglucosamine. One of these, referred to as WlbB, is an N-acetyltransferase that converts UDP-2-acetamido-3-amino-2,3-dideoxy-D-glucuronic acid (UDP-GlcNAc3NA) to UDP-2,3-diacetamido-2,3-dideoxy-D-glucuronic acid (UDP-GlcNAc3NAcA). Here we report the three-dimensional structure of WlbB from Bordetella petrii. For this analysis, two ternary structures were determined to 1.43 {angstrom} resolution: one in which the protein was complexed with acetyl-CoA and UDP and the second in which the protein contained bound CoA and UDP-GlcNAc3NA. WlbB adopts a trimericmore » quaternary structure and belongs to the L{beta}H superfamily of N-acyltransferases. Each subunit contains 27 {beta}-strands, 23 of which form the canonical left-handed {beta}-helix. There are only two hydrogen bonds that occur between the protein and the GlcNAc3NA moiety, one between O{sup {delta}1} of Asn 84 and the sugar C-3{prime} amino group and the second between the backbone amide group of Arg 94 and the sugar C-5{prime} carboxylate. The sugar C-3{prime} amino group is ideally positioned in the active site to attack the si face of acetyl-CoA. Given that there are no protein side chains that can function as general bases within the GlcNAc3NA binding pocket, a reaction mechanism is proposed for WlbB whereby the sulfur of CoA ultimately functions as the proton acceptor required for catalysis.« less

Metal chelates of phosphonate-containing ligands-III Analytical applications of N,N,N',N'-ethylenediaminetetra(methylenephosphonic) acid.

PubMed

Zaki, M T; Rizkalla, E N

1980-05-01

N,N*,N',N'-Ethylenediaminetetra(methylenephosphonic) acid is used as a titrant for the direct determination of Cu, Co and Ni, with murexide as indicator. Indirect titrimetric procedures are suggested for the determination of silver, mercury, zinc and cyanide and both direct and indirect methods are applied for the analysis of binary mixtures of silver (or mercury) and copper (cobalt or nickel). The stoichiometry of the reaction, interferences of some metal ions and the pH effects on the complexation reactions are discussed. The values of the equilibrium constants of the protonated CuH(n)L (n = 1, 2, 3 and 4) as well as the unprotonated CuL chelates have been measured.

Dietary n-6 and n-3 fatty acids in immunity and autoimmune disease.

PubMed

Harbige, L S

1998-11-01

Clearly there is much evidence to show that under well-controlled laboratory and dietary conditions fatty acid intake can have profound effects on animal models of autoimmune disease. Studies in human autoimmune disease have been less dramatic; however, human trials have been subject to uncontrolled dietary and genetic backgrounds, infection and other environmental influences, and basic trial designs have been inadequate. The impact of dietary fatty acids on animal autoimmune disease models appears to depend on the animal model and the type and amount of fatty acids fed. Diets low in fat, essential fatty acid-deficient, or high in n-3 fatty acids from fish oils increase the survival and reduce disease severity in spontaneous autoantibody-mediated disease, whilst linoleic acid-rich diets appear to increase disease severity. In experimentally-induced T-cell-mediated autoimmune disease, essential fatty acid-deficient diets or diets supplemented with n-3 fatty acids appear to augment disease, whereas n-6 fatty acids prevent or reduce the severity. In contrast, in both T-cell and antibody-mediated auto-immune disease the desaturated and elongated metabolites of linoleic acid are protective. Suppression of autoantibody and T lymphocyte proliferation, apoptosis of autoreactive lymphocytes, and reduced pro-inflammatory cytokine production by high-dose fish oils are all likely mechanisms by which n-3 fatty acids ameliorate autoimmune disease. However, these could be undesirable long-term effects of high-dose fish oil which may compromise host immunity. The protective mechanism(s) of n-6 fatty acids in T-cell- mediated autoimmune disease are less clear, but may include dihomo-gamma-linolenic acid- and arachidonic acid-sensitive immunoregulatory circuits such as Th1 responses, TGF beta 1-mediated effects and Th3-like responses. It is often claimed that n-6 fatty acids promote autoimmune and inflammatory disease based on results obtained with linoleic acid only. It should be

Membrane topology of rat sodium-coupled neutral amino acid transporter 2 (SNAT2).

PubMed

Ge, Yudan; Gu, Yanting; Wang, Jiahong; Zhang, Zhou

2018-07-01

Sodium-coupled neutral amino acid transporter 2 (SNAT2) is a subtype of the amino acid transport system A that is widely expressed in mammalian tissues. It plays critical roles in glutamic acid-glutamine circulation, liver gluconeogenesis and other biological pathway. However, the topology of the SNAT2 amino acid transporter is unknown. Here we identified the topological structure of SNAT2 using bioinformatics analysis, Methoxy-polyethylene glycol maleimide (mPEG-Mal) chemical modification, protease cleavage assays, immunofluorescence and examination of glycosylation. Our results show that SNAT2 contains 11 transmembrane domains (TMDs) with an intracellular N terminus and an extracellular C terminus. Three N-glycosylation sites were verified at the largest extracellular loop. This model is consistent with the previous model of SNAT2 with the exception of a difference in number of glycosylation sites. This is the first time to confirm the SNAT2 membrane topology using experimental methods. Our study on SNAT2 topology provides valuable structural information of one of the solute carrier family 38 (SLC38) members. Copyright © 2018 Elsevier B.V. All rights reserved.

Return of the lysergamides. Part II: Analytical and behavioural characterization of N6 -allyl-6-norlysergic acid diethylamide (AL-LAD) and (2'S,4'S)-lysergic acid 2,4-dimethylazetidide (LSZ).

PubMed

Brandt, Simon D; Kavanagh, Pierce V; Westphal, Folker; Elliott, Simon P; Wallach, Jason; Colestock, Tristan; Burrow, Timothy E; Chapman, Stephen J; Stratford, Alexander; Nichols, David E; Halberstadt, Adam L

2017-01-01

Lysergic acid N,N-diethylamide (LSD) is perhaps one of the most intriguing psychoactive substances known and numerous analogs have been explored to varying extents in previous decades. In 2013, N 6 -allyl-6-norlysergic acid diethylamide (AL-LAD) and (2'S,4'S)-lysergic acid 2,4-dimethylazetidide (LSZ) appeared on the 'research chemicals'/new psychoactive substances (NPS) market in both powdered and blotter form. This study reports the analytical characterization of powdered AL-LAD and LSZ tartrate samples and their semi-quantitative determination on blotter paper. Included in this study was the use of nuclear magnetic resonance (NMR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), low and high mass accuracy electrospray MS(/MS), high performance liquid chromatography diode array detection and GC solid-state infrared analysis. One feature shared by serotonergic psychedelics, such as LSD, is the ability to mediate behavioural responses via activation of 5-HT 2A receptors. Both AL-LAD and LSZ displayed LSD-like responses in male C57BL/6 J mice when employing the head-twitch response (HTR) assay. AL-LAD and LSZ produced nearly identical inverted-U-shaped dose-dependent effects, with the maximal responses occurring at 200 µg/kg. Analysis of the dose responses by nonlinear regression confirmed that LSZ (ED 50  = 114.2 nmol/kg) was equipotent to LSD (ED 50  = 132.8 nmol/kg) in mice, whereas AL-LAD was slightly less potent (ED 50  = 174.9 nmol/kg). The extent to which a comparison in potency can be translated directly to humans requires further investigation. Chemical and pharmacological data obtained from NPS may assist research communities that are interested in various aspects related to substance use and forensic identification. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Cysteine Substitution of Transmembrane Domain Amino Acids Alters the Ethanol Inhibition of GluN1/GluN2A N-Methyl-d-Aspartate Receptors

PubMed Central

Xu, Minfu; Smothers, C. Thetford

2015-01-01

N-Methyl-d-aspartate receptors (NMDARs) are inhibited by behaviorally relevant concentrations of ethanol, and residues within transmembrane (TM) domains of NMDARs, including TM3 GluN1 phenylalanine 639 (F639), regulate this sensitivity. In the present study, we used cysteine (C) mutagenesis to determine whether there are additional residues within nearby TM domains that regulate ethanol inhibition on NMDARs. GluN1(F639C)/GluN2A receptors were less inhibited by ethanol than wild-type receptors, and inhibition was restored to wild-type levels following treatment with ethanol-like methanethiosulfonate reagents. Molecular modeling identified six residues in the GluN1 TM1 domain (valine V566; serine S569) and the GluN2A TM4 domain (methionine, M817; V820, F821, and leucine, L824) that were in close vicinity to the TM3 F639 residue, and these were individually mutated to cysteine and tested for ethanol inhibition and receptor function. The F639C-induced decrease in ethanol inhibition was blunted by coexpression of GluN1 TM1 mutants V566C and S569C, and statistically significant interactions were observed for ethanol inhibition among V566C, F639C, and GluN2A TM4 mutants V820C and F821C and S569C, F639C, and GluN2A TM4 mutants F821C and L824C. Ethanol inhibition was also reduced when either GluN1 TM1 mutant V566C or S569C was combined with GluN2A V820C, suggesting a novel TM1:TM4 intrasubunit site of action for ethanol. Cysteines substituted at TM3 and TM4 sites previously suggested to interact with ethanol had less dramatic effects on ethanol inhibition. Overall, the results from these studies suggest that interactions among TM1, TM3, and TM4 amino acids in NMDARs are important determinants of ethanol action at these receptors. PMID:25635140

Adsorption mechanism of 2,4-dichlorophenoxyacetic acid onto nitric-acid-modified activated carbon fiber.

PubMed

Li, Qun; Sun, Jie; Ren, Tianhao; Guo, Lin; Yang, Zhilin; Yang, Qi; Chen, Hai

2018-04-01

Adsorption by carbon materials is one of the relatively fast methods in present research, which is widely used in emergency events. Activated carbon fiber (ACF) modified by nitric acid (N-ACF) was studied in this research to determine the adsorption performance for 2,4-dichlorophenoxyacetic acid (2,4-D). Subsequently, influence factors, adsorption isotherm models, kinetics and thermodynamic were investigated in a batch system to realize this adsorption. Experimental results showed that ACF modified by 0.1M nitric acid had a better removal ability than 2,4-D. Removal rate of 2,4-D by N-ACF was greatly influenced by pH with the optimum pH at 2. The superiority of the Langmuir isotherm model in describing the adsorption equilibrium was revealed by correlation coefficients R2 (R 2  ≥ 0.997). Furthermore, adsorption kinetics was well described by pseudo-second-order model. The results of thermodynamic showed that adsorption was a spontaneous, endothermic process with randomness increasing. Additionally, surface structure properties of adsorbent were characterized by Scanning electron microscopy, Fourier transform infrared spectroscopy, Specific surface area analysis of Brunauer, Emmett and Teller and Boehm's titration. It turned out that the micropore structure and functional groups on N-ACF all can contribute to the removal of 2,4-D.

Non-Covalent Functionalisation of C30 Fullerene by Pyrrole-n-Carboxylic Acid (n=2, 3): Density Functional Theory Studies

NASA Astrophysics Data System (ADS)

Harismah, Kun; Mirzaei, Mahmoud; Ghasemi, Nahid; Nejati, Mohammad

2017-12-01

For functionalisation of a representative C30 fullerene nanostructure by pyrrole-n-carboxylic acid (PnCA; n=2, 3) their stabilities and properties were investigated based on density functional theory calculations. Parallel calculations were also done for C60 fullerene as evidence for comparing the results. Non-covalent interactions are considered to make the functionalised structures. In contrast with the spherical shape of C60, the shape of C30 fullerene is elliptical; therefore, the functionalisation processes were done for both axial and equatorial elliptical positions (AC30 and EC30). The results indicated that both the positions of C30 have almost equivalent chances to be functionalised by PnCA; but functionalisation by P2CA is slightly more favourable than P3CA, either for C60. The illustrated molecular orbitals' distributions indicated that the direction of charge transfer could be considered from PnCA counterparts to fullerene counterparts. The molecular properties indicated more reactivity for C30 than for C60 fullerene. Finally, the atomic scale quadrupole coupling constants indicated different roles for N and O atoms of PnCA in the functionalised models.

Dietary milled flaxseed and flaxseed oil improve N-3 fatty acid status and do not affect glycemic control in individuals with well-controlled type 2 diabetes.

PubMed

Taylor, Carla G; Noto, Amy D; Stringer, Danielle M; Froese, Sylvia; Malcolmson, Linda

2010-02-01

To determine the effects of dietary consumption of milled flaxseed or flaxseed oil on glycemic control, n-3 fatty acid status, anthropometrics, and adipokines in individuals with type 2 diabetes. Thirty-four participants were randomized into a parallel, controlled trial. The participants were adults with type 2 diabetes (age 52.4 +/- 1.5 years, body mass index 32.4 +/- 1.0 kg/m(2), n = 17 men and 17 women). Participants consumed a selection of bakery products containing no flax (control group [CTL], n = 9), milled flaxseed (FXS, n = 13; 32 g/d), or flaxseed oil (FXO, n = 12; 13 g/d) daily for 12 weeks. The FXS and FXO groups received equivalent amounts of alpha-linolenic acid (ALA; 7.4 g/day). The primary outcome measures were fasting plasma hemoglobin A(1c), glucose, insulin, and phospholipid fatty acid composition. The secondary outcome measures were fasting circulating leptin and adiponectin, as well as body weight, body mass index, and waist circumference. Dietary intake assessment and calculations for homeostasis model assessment for insulin resistance and quantified insulin sensitivity check were also completed. The FXS and FXO groups had increases in plasma phospholipid n-3 fatty acids (ALA, eicosapentaenoic acid [EPA], or decosapentaenoic acid [DPA], but not docosahexaenoic acid), and the FXO group had more EPA and DPA in plasma phospholipids compared to the FXS group. All groups had similar caloric intakes; however, the CTL group experienced a 4% weight gain compared to baseline (p < 0.05), while both flax groups had constant body weights during the study period. All other parameters, including glycemic control, were unchanged by dietary treatment. Milled FXS and FXO intake does not affect glycemic control in adults with well-controlled type 2 diabetes. Possible prevention of weight gain by flax consumption warrants further investigation.

Electron collisions with the HCOOH···(H2O)n complexes (n = 1, 2) in liquid phase: the influence of microsolvation on the π* resonance of formic acid.

PubMed

Freitas, T C; Coutinho, K; Varella, M T do N; Lima, M A P; Canuto, S; Bettega, M H F

2013-05-07

We report momentum transfer cross sections for elastic collisions of low-energy electrons with the HCOOH···(H2O)n complexes, with n = 1, 2, in liquid phase. The scattering cross sections were computed using the Schwinger multichannel method with pseudopotentials in the static-exchange and static-exchange plus polarization approximations, for energies ranging from 0.5 eV to 6 eV. We considered ten different structures of HCOOH···H2O and six structures of HCOOH···(H2O)2 which were generated using classical Monte Carlo simulations of formic acid in aqueous solution at normal conditions of temperature and pressure. The aim of this work is to investigate the influence of microsolvation on the π* shape resonance of formic acid. Previous theoretical and experimental studies reported a π* shape resonance for HCOOH at around 1.9 eV. This resonance can be either more stable or less stable in comparison to the isolated molecule depending on the complex structure and the water role played in the hydrogen bond interaction. This behavior is explained in terms of (i) the polarization of the formic acid molecule due to the water molecules and (ii) the net charge of the solute. The proton donor or acceptor character of the water molecules in the hydrogen bond is important for understanding the stabilization versus destabilization of the π* resonances in the complexes. Our results indicate that the surrounding water molecules may affect the lifetime of the π* resonance and hence the processes driven by this anion state, such as the dissociative electron attachment.

N-nitrosations of basic amino acid residues in polypeptide.

PubMed

Kuo, Wu-Nan; Ivy, Dynisha; Guruvadoo, Luvina; White, Atavia; Graham, Latia

2004-09-01

Changes in the electrophoretic pattern were noted in the products of polypeptides of identical basic amino acids preincubated with reactive or degraded PN, suggesting the occurrence of N-nitrosation of the epsilon-amino group of lysine, the guanido group of arginine and the imidazole group of histidine. Additionally, increase in the N-nitroso immunoreactivity of preincubated histones H2A and H2B was detected by Western blot analysis.

The dietary n6:n3 fatty acid ratio during pregnancy is inversely associated with child neurodevelopment in the EDEN mother-child cohort.

PubMed

Bernard, Jonathan Y; De Agostini, Maria; Forhan, Anne; de Lauzon-Guillain, Blandine; Charles, Marie-Aline; Heude, Barbara

2013-09-01

Long-chain polyunsaturated fatty acids (LC-PUFAs) of the n6 (ω6) and n3 series are essential for the development of a child's brain. Fetal LC-PUFA exposure as well as infant exposure via breast milk depend on the maternal intake of these LC-PUFAs and of their respective dietary precursors (PUFAs). We aimed to investigate the associations between maternal LC-PUFA and PUFA [(LC)PUFA] dietary intake during pregnancy and child neurodevelopment at ages 2 and 3 y. In 1335 mother-child pairs from the EDEN cohort, we evaluated associations between daily maternal (LC)PUFA intake during the last 3 months of pregnancy with the child's language at age 2 y and with different assessments of development at age 3 y. Associations were investigated separately in breastfed and never-breastfed children. We examined interactions between the ratios of n6 and n3 (LC)PUFA intakes (n6:n3 fatty acid ratio) and duration of breastfeeding. Breastfeeding mothers had a lower n6:n3 fatty acid ratio (8.4 vs. 8.8; P = 0.02). Among never-breastfed children (n = 338), we found negative associations between maternal dietary n6:n3 fatty acid ratios and neurodevelopment, as reflected by the child's language at age 2 y (β ± SE = -2.1 ± 0.7; P = 0.001) and development assessed with the Ages and Stages Questionnaire at age 3 y (-1.5 ± 0.8; P = 0.05). Among mothers with a high n6:n3 fatty acid ratio only, breastfeeding duration was positively associated with language at age 2 y (P-interaction < 0.05). This suggests that the ratio between maternal dietary n6 and n3 (LC)PUFA intake possibly influences the child's brain development during fetal life but not during or by breastfeeding. However, breastfeeding might compensate for prenatal imbalance in maternal dietary n6:n3 fatty acid ratio.

Development of luminol-N-hydroxyphthalimide chemiluminescence system for highly selective and sensitive detection of superoxide dismutase, uric acid and Co2.

PubMed

Saqib, Muhammad; Qi, Liming; Hui, Pan; Nsabimana, Anaclet; Halawa, Mohamed Ibrahim; Zhang, Wei; Xu, Guobao

2018-01-15

N-hydroxyphthalimide (NHPI), a well known reagent in organic synthesis and biochemical applications, has been developed as a stable and efficient chemiluminescence coreactant for the first time. It reacts with luminol much faster than N-hydroxysuccinimide, eliminating the need of a prereaction coil used in N-hydroxysuccinimide system. Without using prereaction coil, the chemiluminescence peak intensities of luminol-NHPI system are about 102 and 26 times greater than that of luminol-N-hydroxysuccinimide system and classical luminol-hydrogen peroxide system, respectively. The luminol-NHPI system achieves the highly sensitive detection of luminol (LOD = 70pM) and NHPI (LOD = 910nM). Based on their excellent quenching efficiencies, superoxide dismutase and uric acid are sensitively detected with LODs of 3ng/mL and 10pM, respectively. Co 2+ is also detected a LOD of 30pM by its remarkable enhancing effect. Noteworthily, our method is at least 4 orders of magnitude more sensitive than previously reported uric acid detection methods, and can detect uric acid in human urine and Co 2+ in tap and lake water real samples with excellent recoveries in the range of 96.35-102.70%. This luminol-NHPI system can be an important candidate for biochemical, clinical and environmental analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Multicomponent hydrogen-bonding organic solids constructed from 6-hydroxy-2-naphthoic acid and N-heterocycles: Synthesis, structural characterization and synthon discussion

NASA Astrophysics Data System (ADS)

Zong, Yingxia; Shao, Hui; Pang, Yanyan; Wang, Debao; Liu, Kang; Wang, Lei

2016-07-01

Seven novel multicomponent crystals involving various substituted organic amine molecules and 6-hydroxy-2-naphthoic acid were prepared and characterized by using single crystal X-ray diffraction, infrared and thermogravimetric analyses (TGA). Crystal structures with 1,4-bis(imidazol) butane (L1) 1, 1,4-bis(imidazol-1-ylmethyl)benzene (L2) 2, 1-phenyl piperazine 3, 2-amino-4-hydroxy-6-methyl pyrimidine 4, 4,4'-bipyridine 5, 5,5'-dimethyl-2,2'-dipyridine 6, 2-amino-4,6-dimethyl pyrimidine 7 were determined. Among the seven molecular complexes, total proton transfer from 6-hydroxy-2-naphthoic acid to coformer has occurred in crystals 1-4, while the remaining were cocrystals. X-ray single-crystal structures of these complexes reveal that strong hydrogen bonding O-H···O/N-H···O/O-H···N and weak C-H···O/C-H···π/π···π intermolecular interactions direct the packing modes of molecular crystals together. The analysis of supramolecular synthons in the present structures shows that some classical supramolecular synthons like pyridine-carboxylic acid heterosynthon R22 (7) and aminopyridine-carboxylic acid heterosynthon R22 (8), are again observed in constructing the hydrogen-bonding networks in this paper. Besides, we noticed that water molecules act as a significant hydrogen-bonding connector in constructing supramolecular architectures of 3, 4, 6, and 7.

Microbial Incorporation of Fatty Acids Derived From n-Alkanes Into Glycerides and Waxes

PubMed Central

Davis, J. B.

1964-01-01

When n-alkanes with 13 to 20 carbon atoms were fed to a Nocardia closely related to N. salmonicolor, the produced cellular triglycerides and aliphatic waxes invariably contained fatty acids with an even or an odd number of carbon atoms subject to this feature of the n-alkane substrate. Beta-oxidation and C2 addition are both operative, as evidenced by the spectra of fatty acids incorporated into the cellular lipid components. There is no distinction in the rate of microbial incorporation of the odd-or even-numbered carbon chains. The fatty acids are apparently directly derived from the long chain n-alkanes, rather than synthesized via the classic C2-condensation route. The alcohol component of waxes produced by the Nocardia is invariably of the same chain length as the n-alkane substrate. PMID:14170957

Composition and structure of spontaneously adsorbed monolayers of n-perfluorocarboxylic acids on silver

NASA Astrophysics Data System (ADS)

Chau, Lai-Kwan; Porter, Marc D.

1990-03-01

Monolayer films of n-perfluorocarboxylic acids (CF 3(CF 2) nCOOH, where n = 0-2, 5-8) have been formed by spontaneous adsorption at silver. Infrared reflection spectroscopy, optical ellipsometry, and contact angle measurements indicate that these films exhibit low surface free energies, that the carboxylic acid group is symmetrically bound at the silver substrate as a carboxylate bridging ligand, and that the structure is composed of tilted (≈ 40° from the surface normal) perfluorocarbon chains and small structural defects.

2,3-Diamino-pyridinium sorbate-sorbic acid (1/1).

PubMed

Hemamalini, Madhukar; Goh, Jia Hao; Fun, Hoong-Kun

2012-01-01

In the title mol-ecular salt-adduct, C(5)H(8)N(3) (+)·C(6)H(7)O(2) (-)·C(6)H(8)O(2), the 2,3-diamino-pyridinium cation is essentially planar, with a maximum deviation of 0.013 (2) Å, and is protanated at its pyridine N atom. The sorbate anion and sorbic acid mol-ecules exist in extended conformations. In the crystal, the protonated N atom and one of the two amino-group H atoms are hydrogen bonded to the sorbate anion through a pair of N-H⋯O hydrogen bonds, forming an R(1) (2)(6) ring motif. The carboxyl groups of the sorbic acid mol-ecules and the carboxyl-ate groups of the sorbate anions are connected via O-H⋯O hydrogen bonds. Furthermore, the ion pairs and neutral mol-ecules are connected via inter-molecular N-H⋯O hydrogen bonds, forming sheets lying parallel to (100).

Automated synthesis of N-(2-[18 F]Fluoropropionyl)-l-glutamic acid as an amino acid tracer for tumor imaging on a modified [18 F]FDG synthesis module.

PubMed

Liu, Shaoyu; Sun, Aixia; Zhang, Zhanwen; Tang, Xiaolan; Nie, Dahong; Ma, Hui; Jiang, Shende; Tang, Ganghua

2017-06-15

N-(2-[ 18 F]Fluoropropionyl)-l-glutamic acid ([ 18 F]FPGLU) is a potential amino acid tracer for tumor imaging with positron emission tomography. However, due to the complicated multistep synthesis, the routine production of [ 18 F]FPGLU presents many challenging laboratory requirements. To simplify the synthesis process of this interesting radiopharmaceutical, an efficient automated synthesis of [ 18 F]FPGLU was performed on a modified commercial fluorodeoxyglucose synthesizer via a 2-step on-column hydrolysis procedure, including 18 F-fluorination and on-column hydrolysis reaction. [ 18 F]FPGLU was synthesized in 12 ± 2% (n = 10, uncorrected) radiochemical yield based on [ 18 F]fluoride using the tosylated precursor 2. The radiochemical purity was ≥98%, and the overall synthesis time was 35 minutes. To further optimize the radiosynthesis conditions of [ 18 F]FPGLU, a brominated precursor 3 was also used for the preparation of [ 18 F]FPGLU, and the improved radiochemical yield was up to 20 ± 3% (n = 10, uncorrected) in 35 minutes. Moreover, all these results were achieved using the similar on-column hydrolysis procedure on the modified fluorodeoxyglucose synthesis module. Copyright © 2017 John Wiley & Sons, Ltd.

Synthesis, characterization and antimicrobial activity of novel platinum(IV) and palladium(II) complexes with meso-1,2-diphenyl-ethylenediamine-N,N‧-di-3-propanoic acid - Crystal structure of H2-1,2-dpheddp·2HCl·H2O

NASA Astrophysics Data System (ADS)

Radić, Gordana P.; Glođović, Verica V.; Ratković, Zoran R.; Novaković, Slađana B.; Garcia-Granda, Santiago; Roces, Laura; Menéndez-Taboada, Laura; Radojević, Ivana D.; Stefanović, Olgica D.; Čomić, Ljiljana R.; Trifunović, Srećko R.

2012-12-01

In the reaction of meso-1,2-diphenyl-ethylenediamine (1,2-dphen) with neutralized 3-chlor-propanoic acid, the new linear tetradentate edda-like ligand (edda = ethylenediamine-N,N'-diacetic ion) meso-1,2-diphenyl-ethylenediamine-N,N'-di-3-propanoic acid dihydrochloride monohydrate (H2-1,2-dpheddp·2HCl·H2O) was prepared. The corresponding platinum(IV) complex, s-cis-dichlorido-(meso-1,2-diphenyl-ethylenediamine-N,N'-di-3-propanoate)-platinum(IV) ([PtCl2(1,2-dpheddp)]) was synthesized by heating potassium-hexachloridoplatinate(IV) and H2-1,2-dpheddp·2HCl·H2O on steam bath for 12 h with neutralization by means of lithium-hydroxide. The palladium(II) complex, cis-dichlorido-(meso-1,2-diphenyl-ethylenediamine-N,N'-di-3-propanoate)-palladium(II) ([PdCl2(1,2-dpheddp)]) was obtained in the similar way using potassium-tetrachloridopalladate(II), H2-1,2-dpheddp·2HCl·H2O and lithium-hydroxide. The compounds were characterized by elemental analysis and infrared spectroscopy. The spectroscopically predicted structure of the synthesized tetradentate ligand was confirmed by X-ray analysis of the H2-1,2-dpheddp·2HCl·H2O. Antimicrobial activity of the ligand and corresponding palladium(II) and platinum(IV) complexes is investigated against 25 species of microorganisms. Testing is preformed by microdilution method and minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) have been determined. The difference between antimicrobial activity of the ligand and corresponding platinum(IV) and palladium(II) complex is noticed and, in general, palladium(II) complex was the most active.

1D helix, 2D brick-wall and herringbone, and 3D interpenetration d10 metal-organic framework structures assembled from pyridine-2,6-dicarboxylic acid N-oxide.

PubMed

Wen, Li-Li; Dang, Dong-Bin; Duan, Chun-Ying; Li, Yi-Zhi; Tian, Zheng-Fang; Meng, Qing-Jin

2005-10-03

Five novel interesting d(10) metal coordination polymers, [Zn(PDCO)(H2O)2]n (PDCO = pyridine-2,6-dicarboxylic acid N-oxide) (1), [Zn2(PDCO)2(4,4'-bpy)2(H2O)2.3H2O]n (bpy = bipyridine) (2), [Zn(PDCO)(bix)]n (bix = 1,4-bis(imidazol-1-ylmethyl)benzene) (3), [Zn(PDCO)(bbi).0.5H2O]n (bbi = 1,1'-(1,4-butanediyl)bis(imidazole)) (4), and [Cd(PDCO)(bix)(1.5).1.5H2O]n (5), have been synthesized under hydrothermal conditions and structurally characterized. Polymer 1 possesses a one-dimensional (1D) helical chainlike structure with 4(1) helices running along the c-axis with a pitch of 10.090 Angstroms. Polymer 2 has an infinite chiral two-dimensional (2D) brick-wall-like layer structure in the ac plane built from achiral components, while both 3 and 4 exhibit an infinite 2D herringbone architecture, respectively extended in the ac and ab plane. Polymer 5 features a most remarkable and unique three-dimensional (3D) porous framework with 2-fold interpenetration related by symmetry, which contains channels in the b and c directions, both distributed in a rectangular grid fashion. Compounds 1-5, with systematic variation in dimensionality from 1D to 2D to 3D, are the first examples of d(10) metal coordination polymers into which pyridinedicarboxylic acid N-oxide has been introduced. In addition, polymers 1, 4, and 5 display strong blue fluorescent emissions in the solid state. Polymer 3 exhibits a strong SHG response, estimated to be approximately 0.9 times that of urea.

Pork as a Source of Omega-3 (n-3) Fatty Acids

PubMed Central

Dugan, Michael E.R.; Vahmani, Payam; Turner, Tyler D.; Mapiye, Cletos; Juárez, Manuel; Prieto, Nuria; Beaulieu, Angela D.; Zijlstra, Ruurd T.; Patience, John F.; Aalhus, Jennifer L.

2015-01-01

Pork is the most widely eaten meat in the world, but typical feeding practices give it a high omega-6 (n-6) to omega-3 (n-3) fatty acid ratio and make it a poor source of n-3 fatty acids. Feeding pigs n-3 fatty acids can increase their contents in pork, and in countries where label claims are permitted, claims can be met with limited feeding of n-3 fatty acid enrich feedstuffs, provided contributions of both fat and muscle are included in pork servings. Pork enriched with n-3 fatty acids is, however, not widely available. Producing and marketing n-3 fatty acid enriched pork requires regulatory approval, development costs, quality control costs, may increase production costs, and enriched pork has to be tracked to retail and sold for a premium. Mandatory labelling of the n-6/n-3 ratio and the n-3 fatty acid content of pork may help drive production of n-3 fatty acid enriched pork, and open the door to population-based disease prevention polices (i.e., food tax to provide incentives to improve production practices). A shift from the status-quo, however, will require stronger signals along the value chain indicating production of n-3 fatty acid enriched pork is an industry priority. PMID:26694475

Pork as a Source of Omega-3 (n-3) Fatty Acids.

PubMed

Dugan, Michael E R; Vahmani, Payam; Turner, Tyler D; Mapiye, Cletos; Juárez, Manuel; Prieto, Nuria; Beaulieu, Angela D; Zijlstra, Ruurd T; Patience, John F; Aalhus, Jennifer L

2015-12-16

Pork is the most widely eaten meat in the world, but typical feeding practices give it a high omega-6 (n-6) to omega-3 (n-3) fatty acid ratio and make it a poor source of n-3 fatty acids. Feeding pigs n-3 fatty acids can increase their contents in pork, and in countries where label claims are permitted, claims can be met with limited feeding of n-3 fatty acid enrich feedstuffs, provided contributions of both fat and muscle are included in pork servings. Pork enriched with n-3 fatty acids is, however, not widely available. Producing and marketing n-3 fatty acid enriched pork requires regulatory approval, development costs, quality control costs, may increase production costs, and enriched pork has to be tracked to retail and sold for a premium. Mandatory labelling of the n-6/n-3 ratio and the n-3 fatty acid content of pork may help drive production of n-3 fatty acid enriched pork, and open the door to population-based disease prevention polices (i.e., food tax to provide incentives to improve production practices). A shift from the status-quo, however, will require stronger signals along the value chain indicating production of n-3 fatty acid enriched pork is an industry priority.

Erythrocyte stearidonic acid and other n-3 fatty acids and CHD in the Physicians’ Health Study

USDA-ARS?s Scientific Manuscript database

Intake of marine-based n-3 fatty acids (EPA, docosapentaenoic acid and DHA) is recommended to prevent CHD. Stearidonic acid (SDA), a plant-based n-3 fatty acid, is a precursor of EPA and may be more readily converted to EPA than a-linolenic acid (ALA). While transgenic soyabeans might supply SDA at ...

Pantothenic acid deficiency may increase the urinary excretion of 2-oxo acids and nicotinamide catabolites in rats.

PubMed

Shibata, Katsumi; Inomoto, Kasumi; Nakata, Chifumi; Fukuwatari, Tsutomu

2013-01-01

Pantothenic acid (PaA) is involved in the metabolism of amino acids as well as fatty acid. We investigated the systemic metabolism of amino acids in PaA-deficient rats. For this purpose, urine samples were collected and 2-oxo acids and L-tryptophan (L-Trp) and its metabolites including nicotinamide were measured. Group 1 was freely fed a conventional chemically-defined complete diet and used as an ad lib-fed control, which group was used for showing reference values. Group 2 was freely fed the complete diet without PaA (PaA-free diet) and used as a PaA-deficient group. Group 3 was fed the complete diet, but the daily food amount was equal to the amount of the PaA-deficient group and used as a pair-fed control group. All rats were orally administered 100 mg of L-Trp/kg body weight at 09:00 on day 34 of the experiment and the following 24-h urine samples were collected. The urinary excretion of the sum of pyruvic acid and oxaloacetic acid was higher in rats fed the PaA-free diets than in the rats fed pair-fed the complete diet. PaA deficiency elicited the increased urinary excretion of anthranilic acid and kynurenic acid, while the urinary excretion of xanthurenic acid decreased. The urinary excretion of L-Trp itself, 3-hydroxyanthranilic acid, and quinolinic acid revealed no differences between the rats fed the PaA-free and pair-fed the complete diets. PaA deficiency elicited the increased excretion of N(1)-methylnicotinamide, N(1)-methyl-2-pyridone-5-carboxamide, and N(1)-methyl-4-pyridone-3-carboxamide. These findings suggest that PaA deficiency disturbs the amino acid catabolism.

Dietary fish oil supplements increase tissue n-3 fatty acid composition and expression of delta-6 desaturase and elongase-2 in Jade Tiger hybrid abalone.

PubMed

Mateos, Hintsa T; Lewandowski, Paul A; Su, Xiao Q

2011-08-01

This study was conducted to investigate the effects of fish oil (FO) supplements on fatty acid composition and the expression of ∆6 desaturase and elongase 2 genes in Jade Tiger abalone. Five test diets were formulated to contain 0.5, 1.0, 1.5, 2.0 and 2.5% of FO respectively, and the control diet was the normal commercial abalone diet with no additional FO supplement. The muscle, gonad and digestive glands (DG) of abalone fed with all of the five test diets showed significantly high levels of total n-3 polyunsaturated fatty acid (PUFA), eicosapentaenoic acid (EPA), docosapentaenoic acid n-3 (DPAn-3), and docosahexaenoic acid (DHA) than the control group. In all three types of tissue, abalone fed diet supplemented with 1.5% FO showed the highest level of these fatty acids (P < 0.05). For DPAn-3 the higher level was also found in muscle and gonad of abalone fed diet supplemented with 2% FO (P < 0.05). Elongase 2 expression was markedly higher in the muscle of abalone fed diet supplemented with 1.5% FO (P < 0.05), followed by the diet containing 2% FO supplement. For ∆6 desaturase, significantly higher expression was observed in muscle of abalone fed with diet containing 0.5% FO supplement (P < 0.05). Supplementation with FO in the normal commercial diet can significantly improve long chain n-3 PUFA level in cultured abalone, with 1.5% being the most effective supplementation level.

Hydrogen bonded binary molecular adducts derived from exobidentate N-donor ligand with dicarboxylic acids: Acid⋯imidazole hydrogen-bonding interactions in neutral and ionic heterosynthons

NASA Astrophysics Data System (ADS)

Kathalikkattil, Amal Cherian; Damodaran, Subin; Bisht, Kamal Kumar; Suresh, Eringathodi

2011-01-01

Four new binary molecular compounds between a flexible exobidentate N-heterocycle and a series of dicarboxylic acids have been synthesized. The N-donor 1,4-bis(imidazol-1-ylmethyl)benzene (bix) was reacted with flexible and rigid dicarboxylic acids viz., cyclohexane-1,4-dicarboxylic acid (H 2chdc), naphthalene-1,4-dicarboxylic acid (H 2npdc) and 1H-pyrazole-3,5-dicarboxylic acid (H 2pzdc), generating four binary molecular complexes. X-ray crystallographic investigation of the molecular adducts revealed the primary intermolecular interactions carboxylic acid⋯amine (via O-H⋯N) as well as carboxylate⋯protonated amine (via N-H +⋯O -) within the binary compounds, generating layered and two-dimensional sheet type H-bonded networks involving secondary weak interactions (C-H⋯O) including the solvent of crystallization. Depending on the differences in p Ka values of the selected base/acid (Δp Ka), diverse H-bonded supramolecular assemblies could be premeditated. This study demonstrates the H-bonding interactions between imidazole/imidazolium cation and carboxylic acid/carboxylate anion in providing sufficient driving force for the directed assembly of binary molecular complexes. In the two-component solid form of hetero synthons involving bix and dicarboxylic acid, only H 2chdc exist as cocrystal with bix, while all the other three compounds crystallized exclusively as salt, in agreement with the Δp Ka values predicted for the formation of salts/cocrystals from the base and acid used in the synthesis of supramolecular solids.

Supramolecular architectures in two 1:1 cocrystals of 5-fluorouracil with 5-bromothiophene-2-carboxylic acid and thiophene-2-carboxylic acid.

PubMed

Mohana, Marimuthu; Thomas Muthiah, Packianathan; McMillen, Colin D

2017-06-01

In solid-state engineering, cocrystallization is a strategy actively pursued for pharmaceuticals. Two 1:1 cocrystals of 5-fluorouracil (5FU; systematic name: 5-fluoro-1,3-dihydropyrimidine-2,4-dione), namely 5-fluorouracil-5-bromothiophene-2-carboxylic acid (1/1), C 5 H 3 BrO 2 S·C 4 H 3 FN 2 O 2 , (I), and 5-fluorouracil-thiophene-2-carboxylic acid (1/1), C 4 H 3 FN 2 O 2 ·C 5 H 4 O 2 S, (II), have been synthesized and characterized by single-crystal X-ray diffraction studies. In both cocrystals, carboxylic acid molecules are linked through an acid-acid R 2 2 (8) homosynthon (O-H...O) to form a carboxylic acid dimer and 5FU molecules are connected through two types of base pairs [homosynthon, R 2 2 (8) motif] via a pair of N-H...O hydrogen bonds. The crystal structures are further stabilized by C-H...O interactions in (II) and C-Br...O interactions in (I). In both crystal structures, π-π stacking and C-F...π interactions are also observed.

Palmitic acid (16:0) competes with omega-6 linoleic and omega-3 ɑ-linolenic acids for FADS2 mediated Δ6-desaturation.

PubMed

Park, Hui Gyu; Kothapalli, Kumar S D; Park, Woo Jung; DeAllie, Christian; Liu, Lei; Liang, Allison; Lawrence, Peter; Brenna, J Thomas

2016-02-01

Sapienic acid, 16:1n-10 is the most abundant unsaturated fatty acid on human skin where its synthesis is mediated by FADS2 in the sebaceous glands. The FADS2 product introduces a double bond at the Δ6, Δ4 and Δ8 positions by acting on at least ten substrates, including 16:0, 18:2n-6, and 18:3n-3. Our aim was to characterize the competition for accessing FADS2 mediated Δ6 desaturation between 16:0 and the most abundant polyunsaturated fatty acids (PUFA) in the human diet, 18:2n-6 and 18:3n-3, to evaluate whether competition may be relevant in other tissues and thus linked to metabolic abnormalities associated with FADS2 or fatty acid levels. MCF7 cells stably transformed with FADS2 biosynthesize 16:1n-10 from exogenous 16:0 in preference to 16:1n-7, the immediate product of SCD highly expressed in cancer cell lines, and 16:1n-9 via partial β-oxidation of 18:1n-9. Increasing availability of 18:2n-6 or 18:3n-3 resulted in decreased bioconversion of 16:0 to 16:1n-10, simultaneously increasing the levels of highly unsaturated products. FADS2 cells accumulate the desaturation-elongation products 20:3n-6 and 20:4n-3 in preference to the immediate desaturation products 18:3n-6 and 18:4n-3 implying prompt/coupled elongation of the nascent desaturation products. MCF7 cells incorporate newly synthesized 16:1n-10 into phospholipids. These data suggest that excess 16:0 due to, for instance, de novo lipogenesis from high carbohydrate or alcohol consumption, inhibits synthesis of highly unsaturated fatty acids, and may in part explain why supplemental preformed EPA and DHA in some studies improves insulin resistance and other factors related to diabetes and metabolic syndrome aggravated by excess calorie consumption. Copyright © 2015 Elsevier B.V. All rights reserved.

Aqueous phase hydration and hydrate acidity of perfluoroalkyl and n:2 fluorotelomer aldehydes.

PubMed

Rayne, Sierra; Forest, Kaya

2016-01-01

The SPARC software program and comparative density functional theory (DFT) calculations were used to investigate the aqueous phase hydration equilibrium constants (Khyd) of perfluoroalkyl aldehydes (PFAlds) and n:2 fluorotelomer aldehydes (FTAlds). Both classes are degradation products of known industrial compounds and environmental contaminants such as fluorotelomer alcohols, iodides, acrylates, phosphate esters, and other derivatives, as well as hydrofluorocarbons and hydrochlorofluorocarbons. Prior studies have generally failed to consider the hydration, and subsequent potential hydrate acidity, of these compounds, resulting in incomplete and erroneous predictions as to their environmental behavior. In the current work, DFT calculations suggest that all PFAlds will be dominantly present as the hydrated form in aqueous solution. Both SPARC and DFT calculations suggest that FTAlds will not likely be substantially hydrated in aquatic systems or in vivo. PFAld hydrates are expected to have pKa values in the range of phenols (ca. 9 to 10), whereas n:2 FTAld hydrates are expected to have pKa values ca. 2 to 3 units higher (ca. 12 to 13). In order to avoid spurious modeling predictions and a fundamental misunderstanding of their fate, the molecular and/or dissociated hydrate forms of PFAlds and FTAlds need to be explicitly considered in environmental, toxicological, and waste treatment investigations. The results of the current study will facilitate a more complete examination of the environmental fate of PFAlds and FTAlds.

6-Methyl-1,2,4-benzenetriol, a new intermediate in penicillic acid biosynthesis in Penicillium cyclopium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sekiguchi, J.; Katayama, S.; Yamada, Y.

1987-07-01

Penicillic acid-negative mutants were obtained from a color mutant derived from Penicillium cyclopium NRRL 1888 through N-methyl-N'-nitro-N-nitrosoguanidine treatment. One mutant (SK2N6) accumulated 6-methyl-1,2,4-benzenetriol, which was not previously known to be a metabolite of P. cyclopium, in addition to orsellinic acid and orcinol. The radioactivity of (1-/sup 14/C)acetic acid was rapidly incorporated into 6-methyl-1,2,4-benzenetriol in a culture of P. cyclopium SK2N6. Moreover, the radioactivity of (/sup 14/C)6-methyl-1,2,4-benzenetriol was efficiently incorporated into penicillic acid in a culture of P. cyclopium NRRL 1888. These data indicate that 6-methyl-1,2,4-benzenetriol is a precursor for penicillic acid biosynthesis. The results on the addition of 1,4-dihydroxy-6-methoxy-2-methylbenzene, 6-methoxy-2-methylbenzoquinonemore » (1,4), and 1-O-methylorcinol to a culture of P. cyclopium SK2N6 indicated that only the former two compounds are converted to penicillic acid. Thus, a new portion of the penicillic acid biosynthetic pathway is proposed.« less

Incorporation of N-amidino-pyroglutamic acid into peptides using intramolecular cyclization of alpha-guanidinoglutaric acid.

PubMed

Burov, Sergey; Moskalenko, Yulia; Dorosh, Marina; Shkarubskaya, Zoya; Panarin, Evgeny

2009-11-01

N-terminal modification of peptides by unnatural amino acids significantly affects their enzymatic stability, conformational properties and biological activity. Application of N-amidino-amino acids, positively charged under physiological conditions, can change peptide conformation and its affinity to the corresponding receptor. In this article, we describe synthesis of short peptides, containing a new building block-N-amidino-pyroglutamic acid. Although direct guanidinylation of pyroglutamic acid and oxidation of N-amidino-proline using RuO(4) did not produce positive results, N-amidino-Glp-Phe-OH was synthesized on Wang polymer by cyclization of alpha-guanidinoglutaric acid residue. In the course of synthesis, it was found that literature procedure of selective Boc deprotection using TMSOTf/TEA reagent is accompanied by concomitant side reaction of triethylamine alkylation by polymer linker fragment. It should be mentioned that independently from cyclization time and coupling agent (DIC or HCTU), the lactam formation was incomplete. Separation of the cyclic product from the linear precursor was achieved by HPLC in ammonium formate buffer at pH 6. HPLC analysis showed N-amidino-Glp-Phe-OH stability at acidic and physiological pH and fast ring opening in water solution at pH 9. The suggested method of N-amidino-Glp residue formation can be applied in the case of short peptide chains, whereas synthesis of longer ones will require fragment condensation approach.

Combined effects of π-π stacking and hydrogen bonding on the (N1) acidity of uracil and hydrolysis of 2'-deoxyuridine.

PubMed

Kellie, Jennifer L; Navarro-Whyte, Lex; Carvey, Matthew T; Wetmore, Stacey D

2012-03-01

M06-2X/6-31+G(d,p) is used to study the simultaneous effects of π-π stacking interactions with phenylalanine (modeled as benzene) and hydrogen bonding with small molecules (HF, H(2)O, and NH(3)) on the N1 acidity of uracil and the hydrolytic deglycosylation of 2'-deoxyuridine (dU) (facilitated by fully (OH(-)) or partially (HCOO(-)···H(2)O) activated water). When phenylalanine is complexed with isolated uracil, the proton affinity of all acceptor sites significantly increases (by up to 28 kJ mol(-1)), while the N1 acidity slightly decreases (by ~6 kJ mol(-1)). When small molecules are hydrogen bound to uracil, addition of the phenylalanine ring can increase or decrease the acidity of uracil depending on the number and nature (acidity) of the molecules bound. Furthermore, a strong correlation between the effects of π-π stacking on the acidity of U and the dU deglycosylation reaction energetics is found, where the hydrolysis barrier can increase or decrease depending on the nature and number of small molecules bound, the nucleophile considered (which dictates the negative charge on U in the transition state), and the polarity of the (bulk) environment. These findings emphasize that the catalytic (or anticatalytic) role of the active-site aromatic amino acid residues is highly dependent on the situation under consideration. In the case of uracil-DNA glycosylase (UNG), which catalyzes the hydrolytic excision of uracil from DNA, the type of discrete hydrogen-bonding interactions with U, the nature of the nucleophile, and the anticipated weak, nonpolar environment in the active site suggest that phenylalanine will be slightly anticatalytic in the chemical step, and therefore experimentally observed contributions to catalysis may entirely result from associated structural changes that occur prior to deglycosylation.

An efficient synthesis of the constrained peptidomimetic 2-oxo-3-(N-9-fluorenyloxycarbonylamino)-1-azabicyclo[4.3.0]nonane-9-carboxylic acid from pyroglutamic acid.

PubMed

Mandal, Pijus Kumar; Kaluarachchi, Kumar K; Ogrin, Douglas; Bott, Simon G; McMurray, John S

2005-11-25

[reaction: see text] Azabicyclo[X.Y.0]alkane amino acids are rigid dipeptide mimetics that are useful tools for structure-activity studies in peptide-based drug discovery. Herein, we report an efficient synthesis of three diastereomers of 9-tert-butoxycarbonyl-2-oxo-3-(N-tert-butoxycarbonylamino)-1-azabicyclo[4.3.0]nonane (3S,6S,9S, 3S,6R,9R, and 3S,6R,9S). Methyl N-Boc-pyroglutamate is cleaved with vinylmagnesium bromide to produce an acyclic gamma-vinyl ketone. Michael addition of N-diphenylmethyleneglycine tert-butyl ester produces the N-Boc-delta-oxo-alpha,omega-diaminoazelate intermediate, which, on hydrogenloysis, gives the fused ring system. Acidolytic deprotection followed by Fmoc-protection provided building blocks suitable for solid-phase synthesis.

Three cocrystals and a cocrystal salt of pyrimidin-2-amine and glutaric acid.

PubMed

Odiase, Isaac; Nicholson, Catherine E; Ahmad, Ruksanna; Cooper, Jerry; Yufit, Dmitry S; Cooper, Sharon J

2015-04-01

Four new cocrystals of pyrimidin-2-amine and propane-1,3-dicarboxylic (glutaric) acid were crystallized from three different solvents (acetonitrile, methanol and a 50:50 wt% mixture of methanol and chloroform) and their crystal structures determined. Two of the cocrystals, namely pyrimidin-2-amine-glutaric acid (1/1), C4H5N3·C6H8O4, (I) and (II), are polymorphs. The glutaric acid molecule in (I) has a linear conformation, whereas it is twisted in (II). The pyrimidin-2-amine-glutaric acid (2/1) cocrystal, 2C4H5N3·C6H8O4, (III), contains glutaric acid in its linear form. Cocrystal-salt bis(2-aminopyrimidinium) glutarate-glutaric acid (1/2), 2C4H6N3(+)·C6H6O4(2-)·2C6H8O4, (IV), was crystallized from the same solvent as cocrystal (II), supporting the idea of a cocrystal-salt continuum when both the neutral and ionic forms are present in appreciable concentrations in solution. The diversity of the packing motifs in (I)-(IV) is mainly caused by the conformational flexibility of glutaric acid, while the hydrogen-bond patterns show certain similarities in all four structures.

GluN2B N-methyl-D-aspartate receptor and excitatory amino acid transporter 3 are upregulated in primary sensory neurons after 7 days of morphine administration in rats: implication for opiate-induced hyperalgesia.

PubMed

Gong, Kerui; Bhargava, Aditi; Jasmin, Luc

2016-01-01

The contribution of the peripheral nervous system to opiate-induced hyperalgesia (OIH) is not well understood. In this study, we determined the changes in excitability of primary sensory neurons after sustained morphine administration for 7 days. Changes in the expression of glutamate receptors and glutamate transporters after morphine administration were ascertained in dorsal root ganglions. Patch clamp recordings from intact dorsal root ganglions (ex vivo preparation) of morphine-treated rats showed increased excitability of small diameter (≤30 μm) neurons with respect to rheobase and membrane threshold, whereas the excitability of large diameter (>30 μm) neurons remained unchanged. Small diameter neurons also displayed increased responses to glutamate, which were mediated mainly by GluN2B containing N-methyl-D-aspartate (NMDA) receptors, and to a lesser degree by the neuronal excitatory amino acid transporter 3/excitatory amino acid carrier 1. Coadministration in vivo of the GluN2B selective antagonist Ro 25-6981 with morphine for 7 days prevented the appearance of OIH and increased morphine-induced analgesia. Administration of morphine for 7 days led to an increased expression of GluN2B and excitatory amino acid transporter 3/excitatory amino acid carrier 1, but not of the α-amino-3-hydroxy-5-methyl-4-isoxazole propionate, kainate, or group I metabotropic glutamate receptors, or of the vesicular glutamate transporter 2. These results suggest that peripheral glutamatergic neurotransmission contributes to OIH and that GluN2B subunit of NMDA receptors in the periphery may be a target for therapy.

Effect of n-3 fatty acids on free tryptophan and exercise fatigue.

PubMed

Huffman, Derek M; Altena, Thomas S; Mawhinney, Thomas P; Thomas, Tom R

2004-08-01

Free tryptophan (Trp), which is augmented by liberated free fatty acids (FFA) from adipose tissue, can induce mental fatigue via serotonin during exercise. Since an attenuation in FFA has been observed with omega-3 fatty acid (n-3fa) use, our purpose was to examine the effect of n-3fa supplementation on free Trp availability and exercise fatigue. Ten recreationally trained men ( n=5) and women ( n=5), with maximal oxygen consumption (VO(2max))of 51.6 (3.0) and 44.3 (1.4) ml kg(-1) min(-1), respectively, were studied on two occasions following an overnight fast, before and after n-3fa supplementation (4 g day(-1) for 4 weeks). The exercise trials consisted of a 75-min treadmill run at 60% VO(2max) followed immediately by a high-intensity incremental bout to fatigue. Measurements included exercise monitors, plasma volume (PV), triglycerides (TG), FFA, glycerol, lactate, and glucose. Free Trp and branched-chain amino acids (BCAA) were measured and correlated with time to fatigue; all blood variables were corrected for PV. Free Trp, lactate, glucose, FFA, and glycerol were not significantly different between trials, but TG ( P<0.001) and the free Trp/BCAA ratio were significantly lower after n-3fa use [1.76 (0.18)x10(-2) microg ml(-1)] versus before supplementation [2.17 (0.22), P=0.033]. There was a non-significant increase in time to fatigue after supplementation [10.2 (0.3) min] versus before n-3fa use [9.7 (0.2), P=0.068], and a tendency for higher BCAA levels after supplementation, P=0.068. However, neither free Trp nor the free Trp/BCAA ratio significantly predicted time to fatigue. In conclusion, n-3fa supplementation did not diminish free Trp concentrations or significantly improve endurance performance during a maximal bout of exercise.

Emissions of nitrous acid (HONO), nitric oxide (NO) and nitrous oxide (N2O) from boreal agricultural soil - Effect of N fertilization

NASA Astrophysics Data System (ADS)

Bhattarai, Hem Raj; Virkajärvi, Perttu; -Yli Pirilä, Pasi; Maljanen, Marja

2017-04-01

There is no doubt that nitrogen (N) fertilization has crucial role in increasing food production. However, in parallel it can cause severe impact in environment such as eutrophication, surface/groundwater pollution via nitrate (NO3-) leaching and emissions of N trace gases. Fertilization increases the emissions of nitrous oxide (N2O) which is 260 stronger greenhouse gas than carbon dioxide (CO2). It also enhances the emissions of nitric oxide (NO); an oxidized and very reactive form of nitrogen which can fluctuate the ozone (O3) concentration in atmosphere and cause acidification. The effects of N- fertilization on the emission of N2O and NO from agricultural soil are well known. However, the effects of N fertilization on nitrous acid (HONO) emissions are unknown. Few studies have shown that HONO is emitted from soil but they lack to interlink fertilization and HONO emission. HONO accounts for 17-34 % of hydroxyl (OH-) radical production? in the atmosphere, OH- radicals have vital role in atmospheric chemistry; they can cause photochemical smog, form O3, oxidize volatile organic compounds and also atmospheric methane (CH4). We formulated hypothesis that N fertilization will increase the HONO emissions as it does for N2O and NO. To study this, we took soil samples from agricultural soil receiving different amount of N-fertilizer (0, 250 and 450 kg ha-1) in eastern Finland. HONO emissions were measured by dynamic chamber technique connected with LOPAP (Quma Elektronik & Analytik GmbH), NO by NOx analyzer (Thermo scientific) and static chamber technique and gas chromatograph was used for N2O gas sampling and analysis. Several soil parameters were also measured to establish the relationship between the soil properties, fertilization rate and HONO emission. This study is important because eventually it will open up more questions regarding the forms of N loss from soils and impact of fertilization on atmospheric chemistry.

Catalytic enantioselective silylation of N-sulfonylimines: asymmetric synthesis of α-amino acids from CO2 via stereospecific carboxylation of α-amino silanes.

PubMed

Mita, Tsuyoshi; Sugawara, Masumi; Saito, Keisuke; Sato, Yoshihiro

2014-06-06

A catalytic enantioselective silylation of N-tert-butylsulfonylimines using a Cu-secondary diamine complex was demonstrated. The resulting optically active α-amino silanes could be carboxylated under a CO2 atmosphere (1 atm) to afford the corresponding α-amino acids in a stereoretentive manner. This two-step sequence provides a new synthetic protocol for optically active α-amino acids from gaseous CO2 and imines in the presence of a catalytic amount of a chiral source.

Maternal n-6 and n-3 fatty acid status during pregnancy is related to infant heart rate and heart rate variability: An exploratory study.

PubMed

Drewery, M L; Gaitán, A V; Spedale, S B; Monlezun, C J; Miketínas, D C; Lammi-Keefe, C J

2017-11-01

Early life heart rate (HR) and heart rate variability (HRV) reflect autonomic system maturation. Intervention with n-3 long chain polyunsaturated fatty acids (LCPUFAs) during pregnancy favorably affects fetal HR and HRV, complementing previous observations for n-3 LCPUFA intervention during infancy. The relationship between maternal fatty acid status during pregnancy and infant HR/HRV has not previously been assessed. The aim of this study was to explore associations between maternal n-6 and n-3 fatty acid status during pregnancy and infant HR and HRV at 2 weeks, 4 months, and 6 months of age using linear regression models. Maternal n-3 fatty acids were inversely related to infant HR and positively related to HRV. Conversely, maternal n-6 fatty acids were positively related to infant HR and inversely related to HRV. These data build on existing literature evidencing a role for n-3 fatty acids in accelerating autonomic development and link n-6 fatty acids to HR/HRV. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 721.3821 - L-Glutamic acid, N-(1-oxododecyl)-.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false L-Glutamic acid, N-(1-oxododecyl... Substances § 721.3821 L-Glutamic acid, N-(1-oxododecyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as L-Glutamic acid, N-(1-oxododecyl)- (PMN P...

Facile synthesis and enhanced visible light photocatalytic activity of N and Zr co-doped TiO2 nanostructures from nanotubular titanic acid precursors

NASA Astrophysics Data System (ADS)

Zhang, Min; Yu, Xinluan; Lu, Dandan; Yang, Jianjun

2013-12-01

Zr/N co-doped TiO2 nanostructures were successfully synthesized using nanotubular titanic acid (NTA) as precursors by a facile wet chemical route and subsequent calcination. These Zr/N-doped TiO2 nanostructures made by NTA precursors show significantly enhanced visible light absorption and much higher photocatalytic performance than the Zr/N-doped P25 TiO2 nanoparticles. Impacts of Zr/N co-doping on the morphologies, optical properties, and photocatalytic activities of the NTA precursor-based TiO2 were thoroughly investigated. The origin of the enhanced visible light photocatalytic activity is discussed in detail.

Facile synthesis and enhanced visible light photocatalytic activity of N and Zr co-doped TiO2 nanostructures from nanotubular titanic acid precursors

PubMed Central

2013-01-01

Zr/N co-doped TiO2 nanostructures were successfully synthesized using nanotubular titanic acid (NTA) as precursors by a facile wet chemical route and subsequent calcination. These Zr/N-doped TiO2 nanostructures made by NTA precursors show significantly enhanced visible light absorption and much higher photocatalytic performance than the Zr/N-doped P25 TiO2 nanoparticles. Impacts of Zr/N co-doping on the morphologies, optical properties, and photocatalytic activities of the NTA precursor-based TiO2 were thoroughly investigated. The origin of the enhanced visible light photocatalytic activity is discussed in detail. PMID:24369051

Facile synthesis and enhanced visible light photocatalytic activity of N and Zr co-doped TiO2 nanostructures from nanotubular titanic acid precursors.

PubMed

Zhang, Min; Yu, Xinluan; Lu, Dandan; Yang, Jianjun

2013-12-26

Zr/N co-doped TiO2 nanostructures were successfully synthesized using nanotubular titanic acid (NTA) as precursors by a facile wet chemical route and subsequent calcination. These Zr/N-doped TiO2 nanostructures made by NTA precursors show significantly enhanced visible light absorption and much higher photocatalytic performance than the Zr/N-doped P25 TiO2 nanoparticles. Impacts of Zr/N co-doping on the morphologies, optical properties, and photocatalytic activities of the NTA precursor-based TiO2 were thoroughly investigated. The origin of the enhanced visible light photocatalytic activity is discussed in detail.

n-3 and n-6 Fatty Acid Changes in the Erythrocyte Membranes of Patients with 658240251 Clostridium difficile Infection.

PubMed

Czepiel, Jacek; Gdula-Argasińska, Joanna; Garlicki, Aleksander

2016-01-01

The implications of circulating essential fatty acids (FA) on the inflammatory risk profile and clinical outcome are still unclear. In order to gain a deeper understanding of the role of polyunsaturated fatty acids (PUFA) in the pathogenesis of acute infection, we analyzed the FA content in red blood cell (RBC) membranes of patients with Clostridium difficile infection (CDI) and controls. We prospectively studied 60 patients including 30 patients with CDI and 30 controls to assess lipid concentrations in erythrocyte membranes using gas chromatography. We observed a higher level of saturated fatty acids (SFA) in RBC membranes from patients with CDI. In patients with CDI, we also noticed a higher level of 20:4 n-6 FA and only a small amounts of C20:2n-6, C20:3n-6 FAs, arachidonic acid (AA) precursors, which suggest an intense inflammatory reaction in the organism during infection. We also noticed low levels of n-3 FA in the RBC membranes of patients infected with CDI. There is a deficit of n-3 FA in patients with CDI. n-3 FA are probably used during CDI as precursors of pro-resolving mediators that may indicate a therapeutic role of n-3 PUFAs in CDI. The changes in fatty acids in erythrocyte membranes during CDI alter their functions which may have an impact on the clinical outcome.

Interplay Between n-3 and n-6 Long-Chain Polyunsaturated Fatty Acids and the Endocannabinoid System in Brain Protection and Repair.

PubMed

Dyall, Simon C

2017-11-01

The brain is enriched in arachidonic acid (ARA) and docosahexaenoic acid (DHA), long-chain polyunsaturated fatty acids (LCPUFAs) of the n-6 and n-3 series, respectively. Both are essential for optimal brain development and function. Dietary enrichment with DHA and other long-chain n-3 PUFA, such as eicosapentaenoic acid (EPA), has shown beneficial effects on learning and memory, neuroinflammatory processes, and synaptic plasticity and neurogenesis. ARA, DHA and EPA are precursors to a diverse repertoire of bioactive lipid mediators, including endocannabinoids. The endocannabinoid system comprises cannabinoid receptors, their endogenous ligands, the endocannabinoids, and their biosynthetic and degradation enzymes. Anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are the most widely studied endocannabinoids and are both derived from phospholipid-bound ARA. The endocannabinoid system also has well-established roles in neuroinflammation, synaptic plasticity and neurogenesis, suggesting an overlap in the neuroprotective effects observed with these different classes of lipids. Indeed, growing evidence suggests a complex interplay between n-3 and n-6 LCPUFA and the endocannabinoid system. For example, long-term DHA and EPA supplementation reduces AEA and 2-AG levels, with reciprocal increases in levels of the analogous endocannabinoid-like DHA and EPA-derived molecules. This review summarises current evidence of this interplay and discusses the therapeutic potential for brain protection and repair.

Influence of humic acid concentration on nTiO2 attachment to quartz sand and Fe-coated quartz sand

NASA Astrophysics Data System (ADS)

Cheng, T.; Wu, Y.

2016-12-01

The transport of nano-scale or micro-scale titanium dioxide particles (nTiO2) in subsurface environments are strongly influenced by nTiO2 attachment to sediment grains. The objective of this study is to investigate the role of humic acid (HA) in the attachment of nTiO2 to sand at low HA concentrations that are relevant to typical groundwater conditions, so that mechanisms that control nTiO2 immobilization and transport in groundwater can be elucidated. nTiO2 may carry either positive or negative charges in natural water, therefore, environmental factors such as pH, humic substances, and Fe oxyhydroxide coatings on sediment grains, which are known to control the transport of negatively-charged colloids, may influence nTiO2 in different manners. Attachment of nTiO2 to quartz sand and Fe oxyhydroxide coated quartz sand are experimentally measured under a range of HA concentrations at fixed pH. Experimental results show that at pH 5, negatively-charged HA strongly adsorbs to positively-charged nTiO2 and Fe oxyhydroxide, which, at low HA concentrations, partially neutralizes the positive charges on nTiO2 and Fe oxyhydroxide, and therefore decreases the repulsive electrostatic forces between the surfaces, resulting in relatively high nTiO2 attachment. At high HA concentrations, adsorbed HA reverses the surface charges of nTiO2 and Fe oxyhydroxide, and makes nTiO2 and Fe oxyhydroxide strongly negatively charged, resulting in low nTiO2 attachment. At pH 9, HA, nTiO2, and Fe oxyhydroxide are all negatively charged, and HA adsorption is low and does not have a strong impact on the attachment of nTiO2. This study demonstrates that the changes in surface charges of nTiO2 and Fe oxyhydroxide coating caused by HA adsorption could be a key factor that controls the attachment of nTiO2 to sediment grains.

40 CFR 721.10526 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, telomers with C18-26-alkyl acrylate, 1...

Code of Federal Regulations, 2013 CFR

2013-07-01

...-dodecanethiol, N-(hydroxymethyl)-2-methyl-2-propenamide, polyfluorooctyl methacrylate and vinylidene chloride, 2...-alkyl acrylate, 1-dodecanethiol, N-(hydroxymethyl)-2-methyl-2-propenamide, polyfluorooctyl methacrylate... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 2-Propenoic acid, 2-methyl-, 2...

40 CFR 721.10526 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, telomers with C18-26-alkyl acrylate, 1...

Code of Federal Regulations, 2014 CFR

2014-07-01

...-dodecanethiol, N-(hydroxymethyl)-2-methyl-2-propenamide, polyfluorooctyl methacrylate and vinylidene chloride, 2...-alkyl acrylate, 1-dodecanethiol, N-(hydroxymethyl)-2-methyl-2-propenamide, polyfluorooctyl methacrylate... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 2-Propenoic acid, 2-methyl-, 2...

Dietary Conjugated Linoleic Acid-Enriched Cheeses Influence the Levels of Circulating n-3 Highly Unsaturated Fatty Acids in Humans.

PubMed

Murru, Elisabetta; Carta, Gianfranca; Cordeddu, Lina; Melis, Maria Paola; Desogus, Erika; Ansar, Hastimansooreh; Chilliard, Yves; Ferlay, Anne; Stanton, Catherine; Coakley, Mairéad; Ross, R Paul; Piredda, Giovanni; Addis, Margherita; Mele, Maria Cristina; Cannelli, Giorgio; Banni, Sebastiano; Manca, Claudia

2018-06-11

n-3 highly unsaturated fatty acids (n-3 HUFA) directly and indirectly regulate lipid metabolism, energy balance and the inflammatory response. We investigated changes to the n-3 HUFA score of healthy adults, induced by different types and amounts of conjugated linoleic acid (CLA)-enriched (ENCH) cheeses consumed for different periods of time, compared to dietary fish oil (FO) pills (500 mg, each containing 100 mg of eicosapentaenoic and docosahexaenoic acids—EPA+DHA) or α-linolenic acid (ALA)-rich linseed oil (4 g, containing 2 g of ALA). A significant increase in the n-3 HUFA score was observed, in a dose-dependent manner, after administration of the FO supplement. In terms of the impact on the n-3 HUFA score, the intake of ENCH cheese (90 g/day) for two or four weeks was equivalent to the administration of one or two FO pills, respectively. Conversely, the linseed oil intake did not significantly impact the n-3 HUFA score. Feeding ENCH cheeses from different sources (bovine, ovine and caprine) for two months improved the n-3 HUFA score by increasing plasma DHA, and the effect was proportional to the CLA content in the cheese. We suggest that the improved n-3 HUFA score resulting from ENCH cheese intake may be attributed to increased peroxisome proliferator-activated receptor alpha (PPAR-α) activity. This study demonstrates that natural ENCH cheese is an alternative nutritional source of n-3 HUFA in humans.

Metabolomic Profiling of Fatty Acid and Amino Acid Metabolism in Youth With Obesity and Type 2 Diabetes

PubMed Central

Mihalik, Stephanie J.; Michaliszyn, Sara F.; de las Heras, Javier; Bacha, Fida; Lee, SoJung; Chace, Donald H.; DeJesus, Victor R.; Vockley, Jerry; Arslanian, Silva A.

2012-01-01

OBJECTIVE We compared acylcarnitine (AcylCN) species, common amino acid and fat oxidation (FOX) byproducts, and plasma amino acids in normal weight (NW; n = 39), obese (OB; n = 64), and type 2 diabetic (n = 17) adolescents. RESEARCH DESIGN AND METHODS Fasting plasma was analyzed by tandem mass spectrometry, body composition by dual energy X-ray absorptiometry and computed tomography, and total-body lipolysis and substrate oxidation by [2H5]glycerol and indirect calorimetry, respectively. In vivo insulin sensitivity (IS) was assessed with a 3-h hyperinsulinemic-euglycemic clamp. RESULTS Long-chain AcylCNs (C18:2-CN to C14:0-CN) were similar among the three groups. Medium- to short-chain AcylCNs (except C8 and C10) were significantly lower in type 2 diabetes compared with NW, and when compared with OB, C2-, C6-, and C10-CN were lower. Amino acid concentrations were lower in type 2 diabetes compared with NW. Fasting lipolysis and FOX were higher in OB and type 2 diabetes compared with NW, and the negative association of FOX to C10:1 disappeared after controlling for adiposity, Tanner stage, and sex. IS was lower in OB and type 2 diabetes with positive associations between IS and arginine, histidine, and serine after adjusting for adiposity, Tanner stage, and sex. CONCLUSIONS These metabolomics results, together with the increased rates of in vivo FOX, are not supportive of defective fatty acid or amino acid metabolism in obesity and type 2 diabetes in youth. Such observations are consistent with early adaptive metabolic plasticity in youth, which over time—with continued obesity and aging—may become dysfunctional, as observed in adults. PMID:22266733

β-N-oxalyl-L-α, β- diaminopropionic acid induces HRE expression by inhibiting HIF-prolyl hydroxylase-2 in normoxic conditions.

PubMed

Eslavath, Ravi Kumar; Sharma, Deepshikha; Bin Omar, Nabil A M; Chikati, Rajasekhar; Teli, Mahesh Kumar; Rajanikant, G K; Singh, Surya S

2016-11-15

Hypoxia inducible factor (HIF)-1α, a subunit of HIF transcription factor, regulates cellular response to hypoxia. In normoxic conditions, it is hydroxylated by prolyl hydroxylase (PHD)-2 and targeted for proteosomal degradation. Drugs which inhibit PHD-2 have implications in conditions arising from insufficient blood supply. β-ODAP (β-N- oxalyl-L-α, β- diaminopropionic acid), a non-protein excitatory amino acid present in Lathyrus sativus, is an α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor agonist known to activate conventional protein kinase C and stabilize HIF-1α under normoxic conditions. However, the mechanism of HIF-1α stabilization by this compound is unknown. In silico approach was used to understand the mechanism of stabilization of HIF-1α which revealed β-ODAP interacts with key amino acid residues and Fe 2+ at the catalytic site of PHD-2. These results were further corroborated with luciferase HRE (hypoxia response element) reporter system in HeLa cells. Different chemical modulators of PHD-2 activity and HIF-1α levels were included in the study for comparison. Results obtained indicate that β-ODAP inhibits PHD-2 and facilitates HIF dependent HRE expression and hence, might be helpful in conditions arising from hypoxia. Copyright © 2016 Elsevier B.V. All rights reserved.

A rare positively charged nicotinic acid di­sulfide: 2,2′-di­thio­dinicotinic acid hydro­chloride monohydrate

PubMed Central

McGuire, Chad M.; Albrecht-Schmitt, Thomas E.

2018-01-01

The title compound {systematic name: 3-carb­oxy-2-[2-(3-carb­oxy­pyridin-2-yl)disulfan-1-yl)]pyridin-1-ium chloride monohydrate}, C12H9N2O4S2 +·Cl−·H2O, crystallizes in the triclinic space group P . A pair of 2-mercaptonicotinic acid moieties is connected by a 2,2′-di­sulfide bond with a dihedral angle of 78.79 (3)°. One of the N atom is protonated, as are both carboxyl­ate groups, resulting in an overall +1 charge on the dimer. The structure comprises a zigzagging layer of the dimerized di­thio­dinicotinic acid rings, with charge-balancing chloride ions and water mol­ecules between the layers. Hydrogen bonding between the chloride and water sites with the dimer appears to hold the structure together. Nearest neighbor nicotinic acid rings are offset when viewed down the a axis, suggesting no added stability from ring stacking. The asymmetric unit corresponds to the empirical formula of the compound, and it packs with two formula units per unit cell.

Inhibitory activity and mechanism of inhibition of the N-[[(4-benzoylamino)phenyl]sulfonyl]amino acid aldose reductase inhibitors.

PubMed

DeRuiter, J; Mayfield, C A

1990-11-15

A series of substituted N-[[(4-benzoylamino)phenyl]sulfonyl]amino acids (BAPS-amino acids) were synthesized by established methods, and the stereochemistry of the products was confirmed by HPLC analysis after chiral derivatization. When tested against aldose reductase (alditol:NADP+ oxidoreductase; EC 1.1.1.21; ALR2) isolated from rat lens, all of the BAPS-amino acids were determined to be significantly more inhibitory than the corresponding N-(phenylsulfonyl)amino acids. Structure-inhibition and enzyme kinetic analyses suggest that the BAPS-amino acids inhibit ALR2 by a mechanism similar to the N-(phenylsulfonyl)amino acids. However, multiple inhibition analyses indicate that the increased inhibitory activity of the BAPS-amino acids is a result of interaction with multiple sites present on ALR2. Enzyme specificity studies with several of the BAPS-amino acids demonstrated that these compounds do not produce significant inhibition of other nucleotide-requiring enzymes including aldehyde reductase (alcohol: NADP+ oxidoreductase; EC 1.1.1.2; ALR1).

Shaken not stirred: a facile synthesis of 1,4-bis(furo[2,3-d]-pyrimidine-2,4(1H,3H)-dione-5-yl)benzenes by one-pot reaction of isocyanides, N,N'-dimethylbarbituric acid, and terephthaldialdehyde.

PubMed

Teimouri, Mohammad Bagher; Bazhrang, Reihaneh

2006-07-15

A simple and efficient synthesis of 1,4-bis(furo[2,3-d]pyrimidine-2,4(1H,3H)-dione-5-yl)benzene derivatives was achieved via a one-pot three-component reaction of isocyanides, N,N'-dimethylbarbituric acid, and terephthaldialdehyde in DMF at room temperature for 30 min. These improved reaction conditions allow the preparation of highly substituted furopyrimidinones in high yields and purity under mild reaction conditions.

N-3 poly-unsaturated fatty acids shift estrogen signaling to inhibit human breast cancer cell growth.

PubMed

Cao, Wenqing; Ma, ZhiFan; Rasenick, Mark M; Yeh, ShuYan; Yu, JiangZhou

2012-01-01

Although evidence has shown the regulating effect of n-3 poly-unsaturated fatty acid (n-3 PUFA) on cell signaling transduction, it remains unknown whether n-3 PUFA treatment modulates estrogen signaling. The current study showed that docosahexaenoic acid (DHA, C22:6), eicosapentaenoic acid (EPA, C20:5) shifted the pro-survival and proliferative effect of estrogen to a pro-apoptotic effect in human breast cancer (BCa) MCF-7 and T47D cells. 17 β-estradiol (E2) enhanced the inhibitory effect of n-3 PUFAs on BCa cell growth. The IC50 of DHA or EPA in MCF-7 cells decreased when combined with E2 (10 nM) treatment (from 173 µM for DHA only to 113 µM for DHA+E2, and from 187 µm for EPA only to 130 µm for EPA+E2). E2 also augmented apoptosis in n-3 PUFA-treated BCa cells. In contrast, in cells treated with stearic acid (SA, C18:0) as well as cells not treated with fatty acid, E2 promoted breast cancer cell growth. Classical (nuclear) estrogen receptors may not be involved in the pro-apoptotic effects of E2 on the n-3 PUFA-treated BCa cells because ERα agonist failed to elicit, and ERα knockdown failed to block E2 pro-apoptotic effects. Subsequent studies reveal that G protein coupled estrogen receptor 1 (GPER1) may mediate the pro-apoptotic effect of estrogen. N-3 PUFA treatment initiated the pro-apoptotic signaling of estrogen by increasing GPER1-cAMP-PKA signaling response, and blunting EGFR, Erk 1/2, and AKT activity. These findings may not only provide the evidence to link n-3 PUFAs biologic effects and the pro-apoptotic signaling of estrogen in breast cancer cells, but also shed new insight into the potential application of n-3 PUFAs in BCa treatment.

Chelating agents related to ethylenediamine bis(2-hydroxyphenyl)acetic acid (EDDHA): synthesis, characterization, and equilibrium studies of the free ligands and their Mg2+, Ca2+, Cu2+, and Fe3+ chelates.

PubMed

Yunta, Felipe; García-Marco, Sonia; Lucena, Juan J; Gómez-Gallego, Mar; Alcázar, Roberto; Sierra, Miguel A

2003-08-25

Iron chelates such as ethylenediamine-N,N'-bis(2-hydroxyphenyl)acetic acid (EDDHA) and their analogues are the most efficient soil fertilizers to treat iron chlorosis in plants growing in calcareous soils. EDDHA, EDDH4MA (ethylenediamine-N,N'-bis(2-hydroxy-4-methylphenyl)acetic acid), and EDDCHA (ethylenediamine-N,N'-bis(2-hydroxy-5-carboxyphenyl)acetic acid) are allowed by the European directive, but also EDDHSA (ethylenediamine-N,N'-bis(2-hydroxy-5-sulfonylphenyl)acetic acid) and EDDH5MA (ethylenediamine-N,N'-bis(2-hydroxy-5-methylphenyl)acetic acid) are present in several commercial iron chelates. In this study, these chelating agents as well as p,p-EDDHA (ethylenediamine-N,N'-bis(4-hydroxyphenyl)acetic acid) and EDDMtxA (ethylenediamine-N,N'-bis(2-metoxyphenyl)acetic acid) have been obtained following a new synthetic pathway. Their chemical behavior has been studied to predict the effect of the substituents in the benzene ring on their efficacy as iron fertilizers for soils above pH 7. The purity of the chelating agents has been determined using a novel methodology through spectrophotometric titration at 480 nm with Fe(3+) as titrant to evaluate the inorganic impurities. The protonation constants were determined by both spectrophotometric and potentiometric methods, and Ca(2+) and Mg(2+) stability constants were determined from potentiometric titrations. To establish the Fe(3+) and Cu(2+) stability constants, a new spectrophotometric method has been developed, and the results were compared with those reported in the literature for EDDHA and EDDHMA and their meso- and rac-isomers. pM values have been also determined to provide a comparable basis to establish the relative chelating ability of these ligands. The purity obtained for the ligands is higher than 87% in all cases and is comparable with that obtained by (1)H NMR. No significant differences have been found among ligands when their protonation and stability constants were compared. As expected, no Fe(3

N abundance of nodules as an indicator of N metabolism in n(2)-fixing plants.

PubMed

Shearer, G; Feldman, L; Bryan, B A; Skeeters, J L; Kohl, D H; Amarger, N; Mariotti, F; Mariotti, A

1982-08-01

This paper expands upon previous reports of (15)N elevation in nodules (compared to other tissues) of N(2)-fixing plants. N(2)-Fixing nodules of Glycine max (soybeans), Vigna unguiculata (cowpea), Phaseolus vulgaris (common bean), Phaseolus coccineus (scarlet runner bean), Prosopis glandulosa (mesquite), and Olneya tesota (desert ironwood) were enriched in (15)N. Nodules of Vicia faba (fava beans), Arachis hypogaea (peanut), Trifolium pratense (red clover), Pisum sativum (pea), Lathyrus sativus (grass pea), Medicago sativa (alfalfa), and Lupinus mutabilis (South American lupine) were not; nor were the nodules of nine species of N(2)-fixing nonlegumes. The nitrogen of ineffective nodules of soybeans and cowpeas was not enriched in (15)N. Thus, (15)N elevation in nodules of these plants depends on active N(2)-fixation. Results obtained so far on the generality of (15)N enrichment in N(2)-fixing nodules suggest that only the nodules of plants which actively fix N(2) and which transport allantoin or allantoic acid exhibit (15)N enrichment.

4-Nitro-aniline-picric acid (2/1).

PubMed

Li, Yan-Jun

2009-09-30

In the title adduct, C(6)H(3)N(3)O(7)·0.5C(6)H(6)N(2)O(2), the complete 4-nitro-aniline mol-ecule is generated by a crystallographic twofold axis with two C atoms and two N atoms lying on the axis. The mol-ecular components are linked into two dimensional corrugated layers running parallel to the (001) plane by a combination of inter-molecular N-H⋯O and C-H⋯O hydrogen bonds. The phenolic oxygen and two sets of nitro oxygen atoms in the picric acid were found to be disordered with occupancies of 0.81 (2):0.19 (2) and 0.55 (3):0.45 (3) and 0.77 (4):0.23 (4), respectively.

-HPLC determination of acidic d-amino acids and their N-methyl derivatives in biological tissues

PubMed Central

Tsesarskaia, Mara; Galindo, Erika; Szókán, Gyula; Fisher, George

2015-01-01

d-aspartate (d-Asp) and N-methyl-d-aspartate (NMDA) occur in the neuroendocrine systems of vertebrates and invertebrates where they play a role in hormone release and synthesis, neurotransmission, and memory and learning. N-methyl-d-glutamate (NMDG) has also been detected in marine bivalves. Several methods have been used to detect these amino acids, but they require pretreatment of tissue samples with o-phthaldialdehyde (OPA) to remove primary amino acids which interfere with the detection of NMDA and NMDG. We report here a one step derivatization procedure with the chiral reagent N-α-(5-fluoro-2,4-dinitrophenyl)-(d or l)-valine amide, FDNP-Val-NH2, a close analog of Marfey’s reagent but with better resolution and higher molar absorptivity. The diastereomers formed are separated by HPLC on an ODS-Hypersil column eluted with TFA/water – TFA/MeCN. UV absorption at 340 nm permits detection levels as low as 5–10 picomoles. D-Asp, NMDA and NMDG peaks are not obscured by other primary or secondary amino acids; hence pretreatment of tissues with OPA is not required. This method is highly reliable and fast (less than 40 minutes HPLC run). Using this method, we have detected D-Asp, NMDA and NMDG in several biological tissues (octopus brain, optical lobe, and bucchal mass; foot and mantle of the mollusk Scapharca broughtonii), confirming the results of other researchers. PMID:19277955

Direct N-alkylation of unprotected amino acids with alcohols

PubMed Central

Yan, Tao; Feringa, Ben L.; Barta, Katalin

2017-01-01

N-alkyl amino acids find widespread application as highly valuable, renewable building blocks. However, traditional synthesis methodologies to obtain these suffer from serious limitations, providing a major challenge to develop sustainable alternatives. We report the first powerful catalytic strategy for the direct N-alkylation of unprotected α-amino acids with alcohols. This method is highly selective, produces water as the only side product leading to a simple purification procedure, and a variety of α-amino acids are mono- or di-N-alkylated, in most cases with excellent retention of optical purity. The hydrophobicity of the products is tunable, and even simple peptides are selectively alkylated. An iron-catalyzed route to mono-N-alkyl amino acids using renewable fatty alcohols is also described that represents an ideal green transformation for obtaining fully bio-based surfactants. PMID:29226249

Fast and Facile Synthesis of 4-Nitrophenyl 2-Azidoethylcarbamate Derivatives from N-Fmoc-Protected α-Amino Acids as Activated Building Blocks for Urea Moiety-Containing Compound Library.

PubMed

Chen, Ying-Ying; Chang, Li-Te; Chen, Hung-Wei; Yang, Chia-Ying; Hsin, Ling-Wei

2017-03-13

A fast and facile synthesis of a series of 4-nitrophenyl 2-azidoethylcarbamate derivatives as activated urea building blocks was developed. The N-Fmoc-protected 2-aminoethyl mesylates derived from various commercially available N-Fmoc-protected α-amino acids, including those having functionalized side chains with acid-labile protective groups, were directly transformed into 4-nitrophenyl 2-azidoethylcarbamate derivatives in 1 h via a one-pot two-step reaction. These urea building blocks were utilized for the preparation of a series of urea moiety-containing mitoxantrone-amino acid conjugates in 75-92% yields and parallel solution-phase synthesis of a urea compound library consisted of 30 members in 38-70% total yields.

Azido and tetrazolo 1,2,4,5-tetrazine N-oxides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chavez, David E.; Parrish, Damon A.; Mitchell, Lauren

2017-02-23

This paper presents the synthesis and characterization of the oxidation products of 3,6-diazido-1,2,4,5-tetrazine (1) and 6-amino-[1,5-b]tetrazolo-1,2,4,5-tetrazine (2). 3,6-Diazido-1,2,4,5-tetrazine-1,4-dioxide was produced from oxidation with peroxytrifluoroacetic acid, and more effectively using hypofluorous acid, and 2 can be oxidized to two different products, 6-amino-[1,5-b]tetrazolo-1,2,4,5-tetrazine mono-N-oxide and di-N-oxide. These N-oxide compounds display promising performance properties as energetic materials.

Iron-Catalyzed Intramolecular C(sp(2))-N Cyclization of 1-(N-Arylpyrrol-2-yl)ethanone O-Acetyl Oximes toward Pyrrolo[1,2-a]quinoxaline Derivatives.

PubMed

Zhang, Zhiguo; Li, Junlong; Zhang, Guisheng; Ma, Nana; Liu, Qingfeng; Liu, Tongxin

2015-07-02

An efficient and convenient iron-catalyzed protocol has been developed for the synthesis of substituted pyrrolo[1,2-a]quinoxalines from 1-(N-arylpyrrol-2-yl)ethanone O-acetyl oximes through N-O bond cleavage and intramolecular directed C-H arylation reactions in acetic acid.

The lathyrus toxin, {beta}-N-oxalyl-L-{alpha},{beta}-diaminopropionic acid (ODAP), and homocysteic acid sensitize CA1 pyramidal neurons to cystine and L-2-amino-6-phosphonohexanoic acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chase, L.A.; Peterson, N.L.; Koerner, J.F.

2007-02-15

A brief exposure of hippocampal slices to L-quisqualic acid (QUIS) sensitizes CA1 pyramidal neurons 30- to 250-fold to depolarization by certain excitatory amino acids analogues, e.g., L-2-amino-6-phosphonohexanoic acid (L-AP6), and by the endogenous compound, L-cystine. This phenomenon has been termed QUIS sensitization. A mechanism similar to that previously described for QUIS neurotoxicity has been proposed to describe QUIS sensitization. Specifically, QUIS has been shown to be sequestered into GABAergic interneurons by the System x{sub c} {sup -} and subsequently released by heteroexchange with cystine or L-AP6, resulting in activation of non-NMDA receptors. We now report two additional neurotoxins, the Lathyrusmore » excitotoxin, {beta}-N-oxalyl-L-{alpha},{beta}-diaminopropionic acid (ODAP), and the endogenous compound, L-homocysteic acid (HCA), sensitize CA1 hippocampal neurons > 50-fold to L-AP6 and > 10-fold to cystine in a manner similar to QUIS. While the cystine- or L-AP6-mediated depolarization can be inhibited by the non-NMDA receptor antagonist CNQX in ODAP- or QUIS-sensitized slices, the NMDA antagonist D-AP5 inhibits depolarization by cystine or L-AP6 in HCA-sensitized slices. Thus, HCA is the first identified NMDA agonist that induces phosphonate or cystine sensitization. Like QUIS sensitization, the sensitization evoked by either ODAP or HCA can be reversed by a subsequent exposure to 2 mM {alpha}-aminoadipic acid. Finally, we have demonstrated that there is a correlation between the potency of inducers for triggering phosphonate or cystine sensitivity and their affinities for System x{sub c} {sup -} and either the non-NMDA or NMDA receptor. Thus, the results of this study support our previous model of QUIS sensitization and have important implications for the mechanisms of neurotoxicity, neurolathyrism and hyperhomocystinemia.« less

Potential of ethylenediaminedi(o-hydroxyphenylacetic acid) and N,N'-bis(hydroxybenzyl)ethylenediamine-N,N'-diacetic acid for the determination of metal ions by capillary electrophoresis.

PubMed

Krokhin, O V; Kuzina, O V; Hoshino, H; Shpigun, O A; Yotsuyanagi, T

2000-08-25

Two aromatic polyaminocarboxylate ligands, ethylenediaminedi(o-hydroxyphenylacetic acid) (EDDHA) and N,N'-bis(hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED), were applied for the separation of transition and heavy metal ions by the ion-exchange variant of electrokinetic chromatography. EDDHA structure contains two chiral carbon centers. It makes it impossible to use the commercially available ligand. All the studied metal ions showed two peaks, which correspond to meso and rac forms of the ligand. The separation of metal-HBED chelates was performed using poly(diallyldimethylammonium) polycations in mixed acetate-hydroxide form. Simultaneous separation of nine single- and nine double-charged HBED chelates, including In(III), Ga(III), Co(II)-(III) and Mn(II)-(III) pairs demonstrated the efficiency of 40,000-400,000 theoretical plates. The separation of Co(III), Fe(III) complexes with different arrangements of donor groups and oxidation of Co(II), Mn(H), Fe(II) ions in reaction with HBED have been discussed.

Crystal structures of 4-meth-oxy-benzoic acid-1,3-bis-(pyridin-4-yl)propane (2/1) and biphenyl-4,4'-di-carb-oxy-lic acid-4-meth-oxy-pyridine (1/2).

PubMed

Gotoh, Kazuma; Ishida, Hiroyuki

2017-07-01

The crystal structures of two hydrogen-bonded compounds, namely 4-meth-oxy-benzoic acid-1,3-bis-(pyridin-4-yl)propane (2/1), C 13 H 14.59 N 2 ·C 8 H 7.67 O 3 ·C 8 H 7.74 O 3 , (I), and biphenyl-4,4'-di-carb-oxy-lic acid-4-meth-oxy-pyridine (1/2), C 14 H 9.43 O 4 ·C 6 H 7.32 NO·C 6 H 7.25 NO, (II), have been determined at 93 K. In (I), the asymmetric unit consists of two crystallographically independent 4-meth-oxy-benzoic acid mol-ecules and one 1,3-bis-(pyridin-4-yl)propane mol-ecule. The asymmetric unit of (II) comprises one biphenyl-4,4'-di-carb-oxy-lic acid mol-ecule and two independent 4-meth-oxy-pyridine mol-ecules. In each crystal, the acid and base mol-ecules are linked by short O-H⋯N/N-H⋯O hydrogen bonds, in which H atoms are disordered over the acid O-atom and base N-atom sites, forming a linear hydrogen-bonded 2:1 or 1:2 unit of the acid and the base. The 2:1 units of (I) are linked via C-H⋯π, π-π and C-H⋯O inter-actions into a tape structure along [101], while the 1:2 units of (II) form a double-chain structure along [-101] through π-π and C-H⋯O inter-actions.

Short-term n-3 fatty acid supplementation but not aspirin increases plasma proresolving mediators of inflammation.

PubMed

Barden, Anne; Mas, Emilie; Croft, Kevin D; Phillips, Michael; Mori, Trevor A

2014-11-01

Resolution of inflammation is an active process involving specialized proresolving mediators (SPM) formed from the n-3 fatty acids. This study examined the effect of n-3 fatty acid supplementation and aspirin on plasma SPMs in healthy humans. Healthy volunteers (n = 21) were supplemented with n-3 fatty acids (2.4g/day) for 7 days with random assignment to take aspirin (300 mg/day) or placebo from day 5 to day 7. Blood was collected at baseline (day 0), day 5, and day 7. Plasma 18R/S-HEPE, E-series resolvins, 17R/S-HDHA, D-series resolvins, 14R/S-HDHA, and MaR-1 were measured by LC/MS/MS. At baseline concentrations of E- and D- series resolvins and the upstream precursors 18R/S-HEPE, 17R/S-HDHA ranged from 0.1nM to 0.2nM. 14R/S-HDHA was 3-fold higher than the other SPMs at baseline but MaR-1 was below the limit of detection. Supplementation with n-3 fatty acids significantly increased RvE1, 18R/S-HEPE, 17R/S-HDHA, and 14R/S-HDHA but not other SPMs. The addition of aspirin after 5 days of n-3 fatty acids did not affect concentrations of any SPM. N-3 fatty acid supplementation for 5 days results in concentrations of SPMs that are biologically active in healthy humans. Aspirin administered after n-3 fatty acids did not offer any additional benefit in elevating the levels of SPMs. Copyright © 2014 by the American Society for Biochemistry and Molecular Biology, Inc.

Theoretical stusy of the reaction between 2,2',4' - trihydroxyazobenzene-5-sulfonic acid and zirconium

USGS Publications Warehouse

Fletcher, Mary H.

1960-01-01

Zirconium reacts with 2,2',4'-trihydroxyazobenzene-5-sulfonic acid in acid solutions to Form two complexes in which the ratios of dye to zirconium are 1 to 1 and 2 to 1. Both complexes are true chelates, with zirconium acting as a bridge between the two orthohydroxy dye groups. Apparent equilibrium constants for the reactions to form each of the complexes are determined. The reactions are used as a basis for the determination of the active component in the dye and a graphical method for the determination of reagent purity is described. Four absorption spectra covering the wave length region from 350 to 750 mu are given, which completely define the color system associated with the reactions in solutions where the hydrochloric acid concentration ranges from 0.0064N to about 7N.

Acid-catalyzed ring-opening reactions of a cyclopropanated 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with alcohols.

PubMed

Tait, Katrina; Horvath, Alysia; Blanchard, Nicolas; Tam, William

2017-01-01

The acid-catalyzed ring-opening reactions of a cyclopropanated 3-aza-2-oxabicylic alkene using alcohol nucleophiles were investigated. Although this acid-catalyzed ring-opening reaction did not cleave the cyclopropane unit as planned, this represent the first examples of ring-openings of cyclopropanated 3-aza-2-oxabicyclo[2.2.1]alkenes that lead to the cleavage of the C-O bond instead of the N-O bond. Different acid catalysts were tested and it was found that pyridinium toluenesulfonate in methanol gave the best yields in the ring-opening reactions. The scope of the reaction was successfully expanded to include primary, secondary, and tertiary alcohol nucleophiles. Through X-ray crystallography, the stereochemistry of the product was determined which confirmed an S N 2-like mechanism to form the ring-opened product.

Syntheses and structure characterization of ten acid-base hybrid crystals based on N-containing aromatic brønsted bases and mineral acids

NASA Astrophysics Data System (ADS)

Lin, Zhihao; Jin, Shouwen; Li, Xiaoliang; Xiao, Xiao; Hu, Kaikai; Guo, Ming; Chi, Xinchen; Liu, Hui; Wang, Daqi

2017-10-01

Cocrystallization of the aromatic brønsted bases with a series of mineral acids gave a total of ten hybrid salts with the compositions: (2-methylquinoline)2: (hydrochloride acid): 3H2O [(HL1)+. (L1)·· (Cl-) · (H2O)3] (1), (6-bromobenzo[d]thiazol-2-amine): (hydrochloride acid) [(HL2)+. (Cl-)] (2), (6-bromobenzo[d]thiazol-2-amine): (nitric acid) [(HL2)+. (NO3-)] (3), (6-bromobenzo[d]thiazol-2-amine): (sulfuric acid) [(HL2)+ · (HSO4)-] (4), (6-bromobenzo[d]thiazol-2-amine): (phosphoric acid) [(HL2)+ · (H2PO4)-] (5), (5,7-dimethyl-1,8-naphthyridine-2-amine): (hydrochloride acid): 3H2O [(HL3)+ · (Cl-) (H2O)3] (6), (5,7-dimethyl-1,8-naphthyridine-2-amine): (hydrobromic acid): CH3OH [(HL3)+ · (Br)- · CH3OH] (7), (5,7-dimethyl-1,8-naphthyridine-2-amine): (sulfuric acid): H2O [(HL3)+ · (HSO4)- · H2O] (8), (2-aminophenol): (phosphoric acid) [(HL4)+ · (H2PO4)-] (9), and (2-amino-4-chlorophenol): (phosphoric acid) [(HL5)+ · (H2PO4)-] (10). The ten salts have been characterized by X-ray diffraction analysis, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the ten investigated crystals the ring N of the heterocycle or the NH2 in the aminophenol are protonated when the acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted classical hydrogen bonds between the NH+/NH3+ and deprotonated acidic groups. Further analysis of the crystal packing of the salts indicated that a different family of additional CHsbnd O, CHsbnd Cl, CH3sbnd N, CH3sbnd O, CHsbnd Br, CH3sbnd Br, Brsbnd Cl, Clsbnd S, Osbnd S, Osbnd O, Brsbnd S, Hsbnd H, and π-π associations contribute to the stabilization and expansion of the total high-dimensional frameworks. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical

Forms of n-3 (ALA, C18:3n-3 or DHA, C22:6n-3) Fatty Acids Affect Carcass Yield, Blood Lipids, Muscle n-3 Fatty Acids and Liver Gene Expression in Lambs.

PubMed

Ponnampalam, Eric N; Lewandowski, Paul A; Fahri, Fahri T; Burnett, Viv F; Dunshea, Frank R; Plozza, Tim; Jacobs, Joe L

2015-11-01

The effects of supplementing diets with n-3 alpha-linolenic acid (ALA) and docosahexaenoic acid (DHA) on plasma metabolites, carcass yield, muscle n-3 fatty acids and liver messenger RNA (mRNA) in lambs were investigated. Lambs (n = 120) were stratified to 12 groups based on body weight (35 ± 3.1 kg), and within groups randomly allocated to four dietary treatments: basal diet (BAS), BAS with 10.7 % flaxseed supplement (Flax), BAS with 1.8 % algae supplement (DHA), BAS with Flax and DHA (FlaxDHA). Lambs were fed for 56 days. Blood samples were collected on day 0 and day 56, and plasma analysed for insulin and lipids. Lambs were slaughtered, and carcass traits measured. At 30 min and 24 h, liver and muscle samples, respectively, were collected for determination of mRNA (FADS1, FADS2, CPT1A, ACOX1) and fatty acid composition. Lambs fed Flax had higher plasma triacylglycerol, body weight, body fat and carcass yield compared with the BAS group (P < 0.001). DHA supplementation increased carcass yield and muscle DHA while lowering plasma insulin compared with the BAS diet (P < 0.01). Flax treatment increased (P < 0.001) muscle ALA concentration, while DHA treatment increased (P < 0.001) muscle DHA concentration. Liver mRNA FADS2 was higher and CPT1A lower in the DHA group (P < 0.05). The FlaxDHA diet had additive effects, including higher FADS1 and ACOX1 mRNA than for the Flax or DHA diet. In summary, supplementation with ALA or DHA modulated plasma metabolites, muscle DHA, body fat and liver gene expression differently.

Chelation of UO(2)(2+) by vitamin B6 complex derivatives: synthesis and characterization of [UO2(beta-pyracinide)2(H2O)] and [UO2(Pyr2en)DMSO]Cl2{Pyr2en=N,N'-ethylenebis(pyridoxylideneiminato)}. A useful modeling of assimilation of uranium by living beings.

PubMed

Back, Davi Fernando; de Oliveira, Gelson Manzoni; Lang, Ernesto Schulz

2006-10-01

The vitamin B(6) derivatives 4-pyridoxic acid (anionic) and the Schiff base N,N'-ethylenebis(pyridoxylideneiminato) react with UO(2)(NO(3))(2) * 6H(2)O to give [UO(2)(beta-pyracinide)(2)(H(2)O)] (beta-pyracin=4-pyridoxic acid) and [UO(2)(Pyr(2)en)DMSO]Cl(2)(Pyr(2)en=N,N'-ethylenebis(pyridoxylideneiminato); DMSO=dimethyl sulfoxide). In both compounds the two uranyl oxo ligands set the axis of distorted pentagonal bipyramides. The ability of vitamin B(6) derivatives to react with UO(2)(2+) allowing the chelation of one uranium atom represents a very specific model of assimilation of uranium by living beings. It could also explain the serious damages caused by heavy or radioactive metals like uranium since their complexation "in vivo" by enzymatic systems like pyridoxal phosphate-containing enzymes would lead to a modification of the prosthetic groups of the metalloenzymes with loss of their catalytic activities.

Blood fatty acid changes in healthy young Americans in response to a 10-week diet that increased n-3 and reduced n-6 fatty acid consumption: a randomised controlled trial.

PubMed

Young, Andrew J; Marriott, Bernadette P; Champagne, Catherine M; Hawes, Michael R; Montain, Scott J; Johannsen, Neil M; Berry, Kevin; Hibbeln, Joseph R

2017-05-01

Military personnel generally under-consume n-3 fatty acids and overconsume n-6 fatty acids. In a placebo-controlled, double-blinded study, we investigated whether a diet suitable for implementation in military dining facilities and civilian cafeterias could benefit n-3/n-6 fatty acid status of consumers. Three volunteer groups were provided different diets for 10 weeks. Control (CON) participants consumed meals from the US Military's Standard Garrison Dining Facility Menu. Experimental, moderate (EXP-Mod) and experimental-high (EXP-High) participants consumed the same meals, but high n-6 fatty acid and low n-3 fatty acid containing chicken, egg, oils and food ingredients were replaced with products having less n-6 fatty acids and more n-3 fatty acids. The EXP-High participants also consumed smoothies containing 1000 mg n-3 fatty acids per serving, whereas other participants received placebo smoothies. Plasma and erythrocyte EPA and DHA in CON group remained unchanged throughout, whereas EPA, DHA and Omega-3 Index increased in EXP-Mod and EXP-High groups, and were higher than in CON group after 5 weeks. After 10 weeks, Omega-3 Index in EXP-High group had increased further. No participants exhibited changes in fasting plasma TAG, total cholesterol, LDL, HDL, mood or emotional reactivity. Replacing high linoleic acid (LA) containing foods in dining facility menus with similar high oleic acid/low LA and high n-3 fatty acid foods can improve n-6/n-3 blood fatty acid status after 5 weeks. The diets were well accepted and suitable for implementation in group feeding settings like military dining facilities and civilian cafeterias.

Advanced oxidation chemistry of paracetamol. UV/H(2)O(2)-induced hydroxylation/degradation pathways and (15)N-aided inventory of nitrogenous breakdown products.

PubMed

Vogna, Davide; Marotta, Raffaele; Napolitano, Alessandra; D'Ischia, Marco

2002-08-23

The advanced oxidation chemistry of the antipyretic drug paracetamol (1) with the UV/H(2)O(2) system was investigated by an integrated methodology based on (15)N-labeling and GC-MS, HPLC, and 2D (1)H, (13)C, and (15)N NMR analysis. Main degradation pathways derived from three hydroxylation steps, leading to 1,4-hydroquinone/1,4-benzoquinone, 4-acetylaminocatechol and, to a much lesser extent, 4-acetylaminoresorcine. Oxidation of the primary aromatic intermediates, viz. 4-acetylaminocatechol, 1,4-hydroquinone, 1,4-benzoquinone, and 1,2,4-benzenetriol, resulted in a series of nitrogenous and non-nitrogenous degradation products. The former included N-acetylglyoxylamide, acetylaminomalonic acid, acetylaminohydroxymalonic acid, acetylaminomaleic acid, diastereoisomeric 2-acetylamino-3-hydroxybutanedioic acids, 2-acetylaminobutenedioic acid, 3-acetylamino-4-hydroxy-2-pentenedioic acid, and 2,4-dihydroxy-3-acetylamino-2-pentenedioic acid, as well as two muconic and hydroxymuconic acid derivatives. (15)N NMR spectra revealed the accumulation since the early stages of substantial amounts of acetamide and oxalic acid monoamide. These results provide the first insight into the advanced oxidation chemistry of a 4-aminophenol derivative by the UV/H(2)O(2) system, and highlight the investigative potential of integrated GC-MS/NMR methodologies based on (15)N-labeling to track degradation pathways of nitrogenous species.

Effects of Dietary n-6:n-3 PUFA Ratios on Lipid Levels and Fatty Acid Profile of Cherry Valley Ducks at 15-42 Days of Age.

PubMed

Li, Mengmeng; Zhai, Shuangshuang; Xie, Qiang; Tian, Lu; Li, Xiaocun; Zhang, Jiaming; Ye, Hui; Zhu, Yongwen; Yang, Lin; Wang, Wence

2017-11-22

The objective of this study was to investigate the effects of dietary n-6:n-3 PUFA ratio on growth performance, serum and tissue lipid levels, fatty acid profile, and hepatic expression of fatty acid synthesis genes in ducks. A total of 3168 15-day old ducks were fed different n-6:n-3 PUFA ratios: 13:1 (control), 10:1, 8:1, 6:1, 4:1, and 2:1. The feeding trial lasted 4 weeks. Our results revealed that dietary n-6:n-3 PUFA ratios had no effects on growth performance. The 2:1 group had the highest serum triglyceride levels. Serum total cholesterol and HDL levels were higher in the 13:1 and 8:1 groups than in the 6:1 and 2:1 groups. The concentration of C18:3n-3 in serum and tissues (liver and muscle) increased with decreasing dietary n-6:n-3 PUFA ratios. The hepatic expression of FADS2, ELOVL5, FADS1, and ELOVL2 increased on a quadratic function with decreasing dietary n-6:n-3 PUFA ratios. These results demonstrate that lower dietary n-6:n-3 PUFA ratios had strong effects on the fatty acid profile of edible parts and the deposition of n-3 PUFAs in adipose tissue of ducks.

Age-related changes of n-3 and n-6 polyunsaturated fatty acids in the anterior cingulate cortex of individuals with major depressive disorder.

PubMed

Conklin, Sarah M; Runyan, Caroline A; Leonard, Sherry; Reddy, Ravinder D; Muldoon, Matthew F; Yao, Jeffrey K

2010-01-01

Accumulating evidence finds a relative deficiency of peripheral membrane fatty acids in persons with affective disorders such as unipolar and bipolar depression. Here we sought to investigate whether postmortem brain fatty acids within the anterior cingulate cortex (BA-24) varied according to the presence of major depression at the time of death. Using capillary gas chromatography we measured fatty acids in a depressed group (n=12), and in a control group without lifetime history of psychiatric diagnosis (n=14). Compared to the control group, the depressed group showed significantly lower concentrations of numerous saturated and polyunsaturated fatty acids including both the n-3 and n-6 fatty acids. Additionally, significant correlations between age at death and precursor (or metabolites) in the n-3 fatty acid pathway were demonstrated in the depressed group but not in control subjects. In the n-6 fatty acid family, the ratio of 20:3(n-6)/18:2(n-6) was higher in patients than in control groups, whereas the ratio of 20:4(n-6)/20:3(n-6) was relatively decreased in patients. Lastly, a significant negative correlation between age and the ratio of 20:4(n-6) to 22:6(n-3) was found in patients, but not in controls. Taken together, decreases in 22:6(n-3) may be caused, at least in part, by the diminished formation of 20:5(n-3), which is derived from 20:4(n-3) through a Delta5 desaturase reaction. The present findings from postmortem brain tissue raise the possibility that an increased ratio of 20:4(n-6) to 22:6(n-3) may provide us with a biomarker for depression. Future research should further investigate these relationships. Published by Elsevier Ltd.

Fatty acids of pulmonary surfactant phosphatidylcholine from fetal rabbit lung tissue in culture. Biosynthesis of n-10 monoenoic fatty acids.

PubMed

Longmuir, K J; Resele-Tiden, C; Rossi, M E

1988-08-01

We have previously reported that fetal rabbit lung tissue in organ culture produces a lamellar body material (pulmonary surfactant) with a lower percentage of disaturated phosphatidylcholine than is typically found in rabbit lung in vivo (Longmuir, K.J., C. Resele-Tiden, and L. Sykes. 1985. Biochim. Biophys. Acta. 833: 135-143). This investigation was conducted to identify all fatty acids present in the lamellar body phosphatidylcholine, and to determine whether the low level of disaturated phosphatidylcholine is due to excessive unsaturated fatty acid at position sn-1, sn-2, or both. Fetal rabbit lung tissue, 23 days gestation, was maintained in culture for 7 days in defined (serum-free) medium. Phospholipids were labeled in culture with [1-14C]acetate or [U-14C]glycerol (to follow de novo fatty acid biosynthesis), or with [1-14C]palmitic acid (to follow incorporation of exogenously supplied fatty acid). Radiolabeled fatty acid methyl esters obtained from lamellar body phosphatidylcholine were first separated by reverse-phase thin-layer chromatography (TLC) into two fractions of 1) 14:0 + 16:1 and 2) 16:0 + 18:1. Complete separation of the individual saturated and monoenoic fatty acids was achieved by silver nitrate TLC of the two fractions. Monoenoic fatty acid double bond position was determined by permanganate-periodate oxidation followed by HPLC of the carboxylic acid phenacyl esters. Lamellar body phosphatidylcholine contained four monoenoic fatty acids: 1) palmitoleic acid, 16:1 cis-9; 2) oleic acid, 18:1 cis-9; 3) cis-vaccenic acid, 18:1 cis-11; and 4) 6-hexadecenoic acid, 16:1 cis-6. In addition, 8-octadecenoic acid, 18:1 cis-8, was found in the fatty acids of the tissue homogenate. The abnormally low disaturated phosphatidylcholine content in lamellar body material was the result of abnormally high levels of monoenoic fatty acid (principally 16:1 cis-9) found at position sn-2. Position sn-1 contained normal levels of saturated fatty acid. The biosynthesis

Syntheses, structural, computational, and thermal analysis of acid-base complexes of picric acid with N-heterocyclic bases.

PubMed

Goel, Nidhi; Singh, Udai P

2013-10-10

Four new acid-base complexes using picric acid [(OH)(NO2)3C6H2] (PA) and N-heterocyclic bases (1,10-phenanthroline (phen)/2,2';6',2"-terpyridine (terpy)/hexamethylenetetramine (hmta)/2,4,6-tri(2-pyridyl)-1,3,5-triazine (tptz)) were prepared and characterized by elemental analysis, IR, NMR and X-ray crystallography. Crystal structures provide detailed information of the noncovalent interactions present in different complexes. The optimized structures of the complexes were calculated in terms of the density functional theory. The thermolysis of these complexes was investigated by TG-DSC and ignition delay measurements. The model-free isoconversional and model-fitting kinetic approaches have been applied to isothermal TG data for kinetics investigation of thermal decomposition of these complexes.

Enhancement of acid treated g-C3N4sbnd Cu2O photocatalytic activity by PEG under visible light irradiation

NASA Astrophysics Data System (ADS)

Zuo, Shiyu; Xu, Haiming; Liao, Wei; Sun, Lei; Li, Qiang; Zan, Jie; Zhang, Binyang; Li, Dongya; Xia, Dongsheng

2018-05-01

In this study, g-C3N4sbnd Cu2O was successfully synthesized in the presence of PEG-400 surfactant via an acid treatment hydrothermal method and a high-temperature calcination method. The structures and properties of as-synthesized samples were characterized using a range of techniques, such as XPS, TEM, PL and BET. The g-C3N4sbnd Cu2O heterojunction exhibits the enhanced photocatalytic performance and high stability. It is revealed that the addition of PEG can promote the heterojunction effect of g-C3N4sbnd Cu2O, effectively improving the crystallinity and specific surface area of the photocatalyst, separation efficiency of photocarriers, and light absorption, thus enhancing the photocatalytic performance.

In vivo epithelial wound repair requires mobilization of endogenous intracellular and extracellular calcium.

PubMed

Aihara, Eitaro; Hentz, Courtney L; Korman, Abraham M; Perry, Nicholas P J; Prasad, Vikram; Shull, Gary E; Montrose, Marshall H

2013-11-22

We report that a localized intracellular and extracellular Ca(2+) mobilization occurs at the site of microscopic epithelial damage in vivo and is required to mediate tissue repair. Intravital confocal/two-photon microscopy continuously imaged the surgically exposed stomach mucosa of anesthetized mice while photodamage of gastric epithelial surface cells created a microscopic lesion that healed within 15 min. Transgenic mice with an intracellular Ca(2+)-sensitive protein (yellow cameleon 3.0) report that intracellular Ca(2+) selectively increases in restituting gastric epithelial cells adjacent to the damaged cells. Pretreatment with U-73122, indomethacin, 2-aminoethoxydiphenylborane, or verapamil inhibits repair of the damage and also inhibits the intracellular Ca(2+) increase. Confocal imaging of Fura-Red dye in luminal superfusate shows a localized extracellular Ca(2+) increase at the gastric surface adjacent to the damage that temporally follows intracellular Ca(2+) mobilization. Indomethacin and verapamil also inhibit the luminal Ca(2+) increase. Intracellular Ca(2+) chelation (1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid/acetoxymethyl ester, BAPTA/AM) fully inhibits intracellular and luminal Ca(2+) increases, whereas luminal calcium chelation (N-(2-hydroxyetheyl)-ethylendiamin-N,N,N'-triacetic acid trisodium, HEDTA) blocks the increase of luminal Ca(2+) and unevenly inhibits late-phase intracellular Ca(2+) mobilization. Both modes of Ca(2+) chelation slow gastric repair. In plasma membrane Ca-ATPase 1(+/-) mice, but not plasma membrane Ca-ATPase 4(-/-) mice, there is slowed epithelial repair and a diminished gastric surface Ca(2+) increase. We conclude that endogenous Ca(2+), mobilized by signaling pathways and transmembrane Ca(2+) transport, causes increased Ca(2+) levels at the epithelial damage site that are essential to gastric epithelial cell restitution in vivo.

4,4'-Bipyridine-pyroglutamic acid (1/2).

PubMed

Arman, Hadi D; Kaulgud, Trupta; Tiekink, Edward R T

2009-10-31

In the title co-crystal, C(10)H(8)N(2)·2C(5)H(7)NO(3), the 4,4'-bipyridine mol-ecule [dihedral angle between the pyridine rings = 36.33 (11)°] accepts O-H⋯N hydrogen bonds from the two pyroglutamic (pga) acid mol-ecules. The pga mol-ecules at each end of the trimeric aggregate self-associate via centrosymmetric eight-membered amide {⋯HNCO}(2) synthons, so that the crystal structure comprises one-dimensional supra-molecular chains propagating in [13]. C-H⋯O and π-π stacking inter-actions [centroid-centroid separation = 3.590 (2) Å] consolidate the structure.

Thermodynamic characteristics of the protolytic equilibria of tetramethylenediamine- N,N,N', N'-tetraacetic acid

NASA Astrophysics Data System (ADS)

Gridchin, S. N.; Nikol'skii, V. M.

2014-04-01

The stepwise dissociation constants of tetramethylenediamine- N,N,N', N'-tetraacetic acid (H4L) are determined by means of potentiometry at 298.15 K and ionic strength values of 0.1, 0.5, and 1.0 (KNO3). The heat effects of the dissociation of the betaine groups of the complexone are measured by direct calorimetry. The standard thermodynamic characteristics of the protolytic equilibria of H4L are calculated via combined use of the results from thermochemical and potentiometric studies performed under identical experimental conditions. Our results are compared with the corresponding data on relative compounds.

Sulfuric acid and hydrogen peroxide surface passivation effects on AlGaN/GaN high electron mobility transistors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zaidi, Z. H., E-mail: zaffar.zaidi@sheffield.ac.uk; Lee, K. B.; Qian, H.

2014-12-28

In this work, we have compared SiN{sub x} passivation, hydrogen peroxide, and sulfuric acid treatment on AlGaN/GaN HEMTs surface after full device fabrication on Si substrate. Both the chemical treatments resulted in the suppression of device pinch-off gate leakage current below 1 μA/mm, which is much lower than that for SiN{sub x} passivation. The greatest suppression over the range of devices is observed with the sulfuric acid treatment. The device on/off current ratio is improved (from 10{sup 4}–10{sup 5} to 10{sup 7}) and a reduction in the device sub-threshold (S.S.) slope (from ∼215 to 90 mV/decade) is achieved. The sulfuric acid ismore » believed to work by oxidizing the surface which has a strong passivating effect on the gate leakage current. The interface trap charge density (D{sub it}) is reduced (from 4.86 to 0.90 × 10{sup 12 }cm{sup −2} eV{sup −1}), calculated from the change in the device S.S. The gate surface leakage current mechanism is explained by combined Mott hopping conduction and Poole Frenkel models for both untreated and sulfuric acid treated devices. Combining the sulfuric acid treatment underneath the gate with the SiN{sub x} passivation after full device fabrication results in the reduction of D{sub it} and improves the surface related current collapse.« less

Effects of dietary n-3 fatty acids on the phospholipid molecular species of monkey brain.

PubMed

Lin, D S; Connor, W E; Anderson, G J; Neuringer, M

1990-10-01

We examined the changes in the molecular species of brain ethanolamine glycerophospholipids of monkeys fed diets containing widely ranging amounts of n-3 fatty acids. Two groups of rhesus monkeys were fed pre- and postnatally either a control diet (soy oil; containing 8% of fatty acids as 18:3n-3) or a deficient diet (safflower oil; containing less than 0.3% 18:3n-3). The brains of these animals were analyzed at 22 months of age. A third group of monkeys was fed the safflower oil diet to 22 months of age and then switched to a fish oil diet (28% long-chain n-3 fatty acids) for 1-2 years before autopsy. The molecular species of the diacyl, alkylacyl, and alkenylacyl ethanolamine glycerophospholipids from frontal cortex were separated by HPLC. A total of 24 molecular species were identified. Fatty acids in the sn-2 position differed markedly among the diet groups, but the sn-1 position always contained only 16:0, 18:0, or 18:1. In the diacyl subclass of the control brain, the n-3 molecular species represented 41% of total and the n-6 species 45%, whereas in the deficient brain the n-3 molecular species decreased to 9% and n-6 molecular species increased to 77%. The fatty acid 22:5n-6 did not replace 22:6n-3 in a symmetrical fashion in the molecular species of the deficient brain. In the brains of the fish oil-fed monkeys, the n-3 molecular species amounted to 61% and n-6 molecular species were reduced to 25%. The species 18:1-22:6, 16:0-22:6, and 18:0-22:6 generally changed proportionally in response to diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Structural, electronic properties and stability of metatitanic acid (H 2TiO 3) nanotubes

NASA Astrophysics Data System (ADS)

Enyashin, A. N.; Denisova, T. A.; Ivanovskii, A. L.

2009-12-01

Quite recently, metatitanic acid (H 2TiO 3) has been successfully prepared, which extended the family of known titanic acids H 2Ti nO 2n+1 ( n = 2, 3 and 4). Here the atomic models for nanotubes (NTs) of metatitanic acid are designed and their cohesive and electronic properties are considered depending on their chirality and radii by means of density-functional theory-tight-binding (DFTB) method. Our main findings are that the proposed H 2TiO 3 tubes are stable and that all these NTs will be the insulators (independently from their chirality and the diameters) with forbidden gaps at about ˜4.6 eV. We have found also that aforementioned properties of predicted H 2TiO 3 NTs are very similar with those of recently prepared fabricated nanotubes of polytitanic acids; thus, it is possible to expect that the proposed H 2TiO 3 tubular materials may be fabricated.

Mass spectrometry of analytical derivatives. 1. Cyanide cations in the spectra of N-alkyl-N-perfluoroacyl-α-amino acids and their methyl esters

PubMed Central

Todua, Nino G.; Tretyakov, Kirill V.; Mikaia, Anzor I.

2016-01-01

The central mission for the development of the National Institute of Standards and Technology/National Institutes of Health/Environmental Protection Agency Mass Spectral Library is the acquisition of reference gas chromatography–mass spectrometry data for important compounds and their chemical modification products. The addition of reliable reference data of various derivatives of amino acids to The Library, and the study of their behavior under electron ionization conditions may be useful for their identification, structure elucidation, and a better understanding of the data obtained when the same derivatives are subjected to other ionization methods. N-Alkyl-N-perfluoroacyl derivatives of amino acids readily produce previously unreported alkylnitrilium cations of composition [HC≡N-alkyl]+. Homologous [HC≡N-aryl]+ cations are typical for corresponding N-aryl analogs. The formation of other ions characteristic for these derivatives involves oxygen rearrangement giving rise to ions [CnF2n+1–C≡N+–CnH2n+1] and [CnF2n+1–C≡N+-aryl]. The introduction of an N-benzyl substituent in a molecule favors a process producing benzylidene iminium cations. l-Threonine and l-cysteine derivatives exhibit more fragmentation pathways not typical for other α-amino acids; additionally, the Nω-amino group in l-lysine directs the dissociation process and provides structural information on the substitution at the amino functions in the molecule. PMID:26307698

Heat capacities and thermal diffusivities of n-alkane acid ethyl esters—biodiesel fuel components

NASA Astrophysics Data System (ADS)

Bogatishcheva, N. S.; Faizullin, M. Z.; Nikitin, E. D.

2017-09-01

The heat capacities and thermal diffusivities of ethyl esters of liquid n-alkane acids C n H2 n-1O2C2H5 with the number of carbon atoms in the parent acid n = 10, 11, 12, 14, and 16 are measured. The heat capacities are measured using a DSC 204 F1 Phoenix heat flux differential scanning calorimeter (Netzsch, Germany) in the temperature range of 305-375 K. Thermal diffusivities are measured by means of laser flash method on an LFA-457 instrument (Netzsch, Germany) at temperatures of 305-400 K. An equation is derived for the dependence of the molar heat capacities of the investigated esters on temperature. It is shown that the dependence of molar heat capacity C p,m (298.15 K) on n ( n = 1-6) is close to linear. The dependence of thermal diffusivity on temperature in the investigated temperature range is described by a first-degree polynomial, but thermal diffusivity a (298.15 K) as a function of n has a minimum at n = 5.

Diet effects on urine composition of cattle and N2O emissions.

PubMed

Dijkstra, J; Oenema, O; van Groenigen, J W; Spek, J W; van Vuuren, A M; Bannink, A

2013-06-01

Ruminant production contributes to emissions of nitrogen (N) to the environment, principally ammonia (NH3), nitrous oxide (N2O) and di-nitrogen (N2) to air, nitrate (NO3 -) to groundwater and particulate N to surface waters. Variation in dietary N intake will particularly affect excretion of urinary N, which is much more vulnerable to losses than is faecal N. Our objective is to review dietary effects on the level and form of N excreted in cattle urine, as well as its consequences for emissions of N2O. The quantity of N excreted in urine varies widely. Urinary N excretion, in particular that of urea N, is decreased upon reduction of dietary N intake or an increase in the supply of energy to the rumen microorganisms and to the host animal itself. Most of the N in urine (from 50% to well over 90%) is present in the form of urea. Other nitrogenous components include purine derivatives (PD), hippuric acid, creatine and creatinine. Excretion of PD is related to rumen microbial protein synthesis, and that of hippuric acid to dietary concentration of degradable phenolic acids. The N concentration of cattle urine ranges from 3 to 20 g/l. High-dietary mineral levels increase urine volume and lead to reduced urinary N concentration as well as reduced urea concentration in plasma and milk. In lactating dairy cattle, variation in urine volume affects the relationship between milk urea and urinary N excretion, which hampers the use of milk urea as an accurate indicator of urinary N excretion. Following its deposition in pastures or in animal houses, ubiquitous microorganisms in soil and waters transform urinary N components into ammonium (NH4 +), and thereafter into NO3 - and ultimately in N2 accompanied with the release of N2O. Urinary hippuric acid, creatine and creatinine decompose more slowly than urea. Hippuric acid may act as a natural inhibitor of N2O emissions, but inhibition conditions have not been defined properly yet. Environmental and soil conditions at the site of

Stability of nTiO2 particles and their attachment to sand: Effects of humic acid at different pH.

PubMed

Wu, Yang; Cheng, Tao

2016-01-15

The fate and transport of nano-scale or micro-scale titanium dioxide particles (nTiO2) in subsurface environments are strongly influenced by the stability of nTiO2 and their attachment to sediment grains. nTiO2 may carry either positive or negative charges in natural water, therefore, environmental factors such as pH, humic substances, and Fe oxyhydroxide coatings on sediment grains, which are known to control the stability and transport of negatively-charged colloids, may influence nTiO2 in different manners. The objective of this study is to investigate the effects of pH and humic acid (HA) on the stability and attachment of nTiO2 to sand at HA concentrations that are relevant to typical groundwater conditions, so that mechanisms that control nTiO2 immobilization and transport in natural systems can be elucidated. Stability and attachment of nTiO2 to quartz sand and Fe oxyhydroxide coated quartz sand are experimentally measured under a range of HA concentrations at pH5 and 9. Results show that at pH5, negatively-charged HA strongly adsorbs to positively-charged nTiO2 and Fe oxyhydroxide, which, at low HA concentrations, partially neutralizes the positive charges on nTiO2 and Fe oxyhydroxide, and therefore decreases the repulsive electrostatic forces between the surfaces, resulting in nTiO2 aggregation and attachment. At high HA concentrations, adsorbed HA reverses the surface charges of nTiO2 and Fe oxyhydroxide, and makes nTiO2 and Fe oxyhydroxide strongly negatively charged, resulting in stable nTiO2 suspension and low nTiO2 attachment. At pH9, HA, nTiO2, and Fe oxyhydroxide are all negatively charged, and HA adsorption is low and does not have a strong impact on the stability and attachment of nTiO2. Overall, this study shows that changes in surface charges of nTiO2 and Fe oxyhydroxide coating caused by HA adsorption is a key factor that influences the stability and attachment of nTiO2. Copyright © 2015 Elsevier B.V. All rights reserved.

Inadequate daily intakes of n-3 polyunsaturated fatty acids (PUFA) in the general French population of children (3-10 years) and adolescents (11-17 years): the INCA2 survey.

PubMed

Guesnet, Philippe; Tressou, Jessica; Buaud, Benjamin; Simon, Noëmie; Pasteau, Stéphane

2018-04-23

This paper deals with the dietary daily intakes of main polyunsaturated fatty acids (PUFA) in French children and adolescents. Dietary intakes of main PUFA were determined from a general French population of 1500 children (3-10 years) and adolescents (11-17 years) by using the most recent set of national robust data on food (National Survey INCA 2 performed in 2006 and 2007). Main results showed that mean daily intakes of total fat and n-6 PUFA linoleic acid (LA, 18:2n-6) were close to current recommended values for children and adolescent populations. However, 80% (children) to 90% (adolescents) of our French populations not only ingested low quantities of n-3 long-chain PUFA (docosahexaenoic (22:6n-3) and eicosapentaenoic (20:5n-3) acids) but also very low quantities of alpha-linolenic acid (ALA, 18:3n-3) at the origin of a non-balanced n-6/n-3 ratio. Inadequate consumption of EPA + DHA was also observed in subgroups of infants and adolescent who consumed more than two servings/week of fish. Such disequilibrium in PUFA dietary intakes in favor of n-6 PUFA could have adverse impact on cell membrane incorporation of long-chain n-3 PUFA and deleterious impacts on the health of children and adolescents. Promoting the consumption of both vegetable oils and margarines rich in ALA, and oily fish rich in long-chain n-3 PUFA might improve such PUFA disequilibrium.

Density and viscosity of aqueous blends of N-methyldiethanolamine and 2-amino-2-methyl-1-propanol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Welsh, L.M.; Davis, R.A.

Aqueous solutions of alkanolamines such as N-methyldiethanolamine (MDEA) and 2-amino-2-methyl-1-propanol (AMP) have application in acid gas treatment for the removal of acid gases such as carbon dioxide and hydrogen sulfide. The density and kinematic viscosity of aqueous blends of N-methyldiethanolamine and 2-amino-2-methyl-1-propanol were determined from experiments within the temperature range 10--60 C. The composition of the alkanolamines in water ranged from 5% to 50% by mass.

Evaluating the role of acidic, basic, and polar amino acids and dipeptides on a molecular electrocatalyst for H 2 oxidation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boralugodage, Nilusha Priyadarshani; Arachchige, Rajith Jayasingha; Dutta, Arnab

Amino acids and peptides have been shown to have a significant influence on the H2 production and oxidation reactivity of Ni(P R 2N R’ 2) 2, where P R 2N R’ 2 = 1,5-diaza-3,7-diphosphacyclooctane, R is either phenyl (Ph) or cyclohexyl (Cy), and R’ is either an amino acid or peptide. Most recently, the Ni(P Cy 2Naminoacid 2) 2 complexes (CyAA) have shown enhanced H 2 oxidation rates, water solubility, and in the case of arginine (CyArg) and phenylalanine (CyPhe), electrocatalytic reversibility. Both the backbone –COOH and side chain interactions were shown to be critical to catalytic performance. Here wemore » further investigate the roles of the outer coordination sphere by evaluating amino acids with acidic, basic, and hydrophilic side chains, as well as dipeptides which combine multiple successful features from previous complexes. Six new complexes were prepared, three containing single amino acids: aspartic acid (CyAsp), lysine (CyLys), and serine (CySer) and three containing dipeptides: glycine-phenylalanine (Cy(GlyPhe)), phenylalanine-glycine (Cy(PheGly)), and aspartic acid-phenylananine (Cy(AspPhe)). The resulting catalytic performance demonstrates that complexes need both interactions between side chain and –COOH groups for fast, efficient catalysis. The fastest of all of the catalysts, Cy(AspPhe), had both of these features, while the other dipeptide complexes with an amide replacing the -COOH were both slower; however, the amide group was demonstrated to participate in the proton pathway when side chain interactions are present to position it. Both the hydrophilic and basic side chains, notably lacking in side chain interactions, significantly increased the overpotential, with only modest increases in TOF. Of all of the complexes, only CyAsp was reversible at room temperature, and only in water, the first of these complexes to demonstrate room temperature reversibility in water. These results continue to provide and solidify design rules for

Theoretical studies on the coupling interactions in H2SO4···HOO˙···(H2O)n (n = 0-2) clusters: toward understanding the role of water molecules in the uptake of HOO˙ radical by sulfuric acid aerosols.

PubMed

Li, Ping; Ma, Zhiying; Wang, Weihua; Zhai, Yazhou; Sun, Haitao; Bi, Siwei; Bu, Yuxiang

2011-01-21

A detailed knowledge of coupling interactions among sulfuric acid (H(2)SO(4)), the hydroperoxyl radical (HOO˙), and water molecules (H(2)O) is crucial for the better understanding of the uptake of HOO˙ radicals by sulfuric acid aerosols at different atmospheric humidities. In the present study, the equilibrium structures, binding energies, equilibrium distributions, and the nature of the coupling interactions in H(2)SO(4)···HOO˙···(H(2)O)(n) (n = 0-2) clusters have been systematically investigated at the B3LYP/6-311++G(3df,3pd) level of theory in combination with the atoms in molecules (AIM) theory, natural bond orbital (NBO) method, energy decomposition analyses, and ab initio molecular dynamics. Two binary, five ternary, and twelve tetramer clusters possessing multiple intermolecular H-bonds have been located on their potential energy surfaces. Two different modes for water molecules have been observed to influence the coupling interactions between H(2)SO(4) and HOO˙ through the formations of intermolecular H-bonds with or without breaking the original intermolecular H-bonds in the binary H(2)SO(4)···HOO˙ cluster. It was found that the introduction of one or two water molecules can efficiently enhance the interactions between H(2)SO(4) and HOO˙, implying the positive role of water molecules in the uptake of the HOO˙ radical by sulfuric acid aerosols. Additionally, the coupling interaction modes of the most stable clusters under study have been verified by the ab initio molecular dynamics.

Influence of dietary long-chain n-3 fatty acids from menhaden fish oil on plasma concentrations of alpha-tocopherol in geriatric beagles.

PubMed

Hall, Jean A; Tooley, Katie A; Gradin, Joseph L; Jewell, Dennis E; Wander, Rosemary C

2002-01-01

To determine effects of dietary n-3 fatty acids from Menhaden fish oil on plasma alpha-tocopherol concentrations in Beagles. 32 female Beagles. For 82 days, dogs were fed diets that contained 1 of 2 ratios of n-6:n-3 fatty acids (40:1 [low n-3] and 1.4:1 [high n-3]) and 1 of 3 concentrations of all-rac-alpha-tocopheryl acetate (low, 17 mg/kg of diet; medium, 101 mg/kg; and high, 447 mg/kg) in a 2 X 3 factorial study. Diets high in n-3 fatty acids significantly increased total content of n-3 fatty acids in plasma (17.0 g/100 g of fatty acids), compared with low n-3 diets (2.02 g/100 g of fatty acids). Mean +/- SEM plasma concentration of cholesterol was significantly lower in dogs consuming high n-3 diets (4.59 +/- 0.48 mmol/L), compared with dogs consuming low n-3 diets (5.71 +/- 0.48 mmol/L). A significant interaction existed between the ratio for n-6 and n-3 fatty acids and amount of alpha-tocopheryl acetate in the diet (plasma alpha-tocopherol concentration expressed on a molar basis), because the plasma concentration of alpha-toco-pherol was higher in dogs consuming low n-3 diets, compared with those consuming high n-3 diets, at the 2 higher amounts of dietary alpha-tocopheryl acetate. Plasma alpha-tocopherol concentration expressed relative to total lipid content did not reveal effects of dietary n-3 fatty acids on concentration of alpha-tocopherol. Plasma alpha-tocopherol concentration is not dependent on dietary ratio of n-6 and n-3 fatty acids when alpha-tocopherol concentration is expressed relative to the total lipid content of plasma.

Anthocyanins do not influence long-chain n-3 fatty acid status: studies in cells, rodents and humans.

PubMed

Vauzour, David; Tejera, Noemi; O'Neill, Colette; Booz, Valeria; Jude, Baptiste; Wolf, Insa M A; Rigby, Neil; Silvan, Jose Manuel; Curtis, Peter J; Cassidy, Aedin; de Pascual-Teresa, Sonia; Rimbach, Gerald; Minihane, Anne Marie

2015-03-01

Increased tissue status of the long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) is associated with cardiovascular and cognitive benefits. Limited epidemiological and animal data suggest that flavonoids, and specifically anthocyanins, may increase EPA and DHA levels, potentially by increasing their synthesis from the shorter-chain n-3 PUFA, α-linolenic acid. Using complimentary cell, rodent and human studies we investigated the impact of anthocyanins and anthocyanin-rich foods/extracts on plasma and tissue EPA and DHA levels and on the expression of fatty acid desaturase 2 (FADS2), which represents the rate limiting enzymes in EPA and DHA synthesis. In experiment 1, rats were fed a standard diet containing either palm oil or rapeseed oil supplemented with pure anthocyanins for 8 weeks. Retrospective fatty acid analysis was conducted on plasma samples collected from a human randomized controlled trial where participants consumed an elderberry extract for 12 weeks (experiment 2). HepG2 cells were cultured with α-linolenic acid with or without select anthocyanins and their in vivo metabolites for 24 h and 48 h (experiment 3). The fatty acid composition of the cell membranes, plasma and liver tissues were analyzed by gas chromatography. Anthocyanins and anthocyanin-rich food intake had no significant impact on EPA or DHA status or FADS2 gene expression in any model system. These data indicate little impact of dietary anthocyanins on n-3 PUFA distribution and suggest that the increasingly recognized benefits of anthocyanins are unlikely to be the result of a beneficial impact on tissue fatty acid status. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Anthocyanins do not influence long-chain n-3 fatty acid status: studies in cells, rodents and humans☆

PubMed Central

Vauzour, David; Tejera, Noemi; O'Neill, Colette; Booz, Valeria; Jude, Baptiste; Wolf, Insa M.A.; Rigby, Neil; Silvan, Jose Manuel; Curtis, Peter J.; Cassidy, Aedin; de Pascual-Teresa, Sonia; Rimbach, Gerald; Minihane, Anne Marie

2015-01-01

Increased tissue status of the long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) is associated with cardiovascular and cognitive benefits. Limited epidemiological and animal data suggest that flavonoids, and specifically anthocyanins, may increase EPA and DHA levels, potentially by increasing their synthesis from the shorter-chain n-3 PUFA, α-linolenic acid. Using complimentary cell, rodent and human studies we investigated the impact of anthocyanins and anthocyanin-rich foods/extracts on plasma and tissue EPA and DHA levels and on the expression of fatty acid desaturase 2 (FADS2), which represents the rate limiting enzymes in EPA and DHA synthesis. In experiment 1, rats were fed a standard diet containing either palm oil or rapeseed oil supplemented with pure anthocyanins for 8 weeks. Retrospective fatty acid analysis was conducted on plasma samples collected from a human randomized controlled trial where participants consumed an elderberry extract for 12 weeks (experiment 2). HepG2 cells were cultured with α-linolenic acid with or without select anthocyanins and their in vivo metabolites for 24 h and 48 h (experiment 3). The fatty acid composition of the cell membranes, plasma and liver tissues were analyzed by gas chromatography. Anthocyanins and anthocyanin-rich food intake had no significant impact on EPA or DHA status or FADS2 gene expression in any model system. These data indicate little impact of dietary anthocyanins on n-3 PUFA distribution and suggest that the increasingly recognized benefits of anthocyanins are unlikely to be the result of a beneficial impact on tissue fatty acid status. PMID:25573539

Effect of the ratio of dietary n-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid on broiler breeder performance, egg quality, and yolk fatty acid composition at different breeder ages.

PubMed

Koppenol, A; Delezie, E; Aerts, J; Willems, E; Wang, Y; Franssens, L; Everaert, N; Buyse, J

2014-03-01

When added to the feed of broiler breeder hens, dietary polyunsaturated fatty acids (FA) can be incorporated into the yolk and therefore become available to the progeny during their early development. The mechanism involved in lipid metabolism and deposition in the egg may be influenced by breeder age. Before the effect of an elevated concentration of certain polyunsaturated FA on the embryo can be investigated, the effect at breeder level and egg quality must be further assessed. The aim of the present experiment was to evaluate the effects of dietary n-6/n-3 ratios and dietary eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) ratios, provided to broiler breeder hens, in terms of their zoo technical performance, egg quality, and yolk FA composition. Starting at 6 wk of age, 640 Ross-308 broiler breeder hens were fed 1 of 4 different diets. The control diet was a basal diet, rich in n-6 FA. The 3 other diets were enriched in n-3 FA, formulated to obtain a different EPA/DHA ratio of 1/1 (EPA = DHA), 1/2 (DHA), or 2/1 (EPA). In fact, after analysis the EPA/DHA ratio was 0.8, 0.4, or 2.1, respectively. Dietary EPA and DHA addition did not affect the performance of the breeder hens, except for egg weight. Egg weight was lower (P < 0.001) for all n-3 treatments. Dietary EPA improved number of eggs laid in the first 2 wk of the production cycle (P = 0.029). The absolute and relative yolk weight of eggs laid by EPA = DHA fed hens was lowest (P = 0.004 and P = 0.025, respectively). The EPA and DHA concentrations in the yolk were highly dependent on dietary EPA and DHA concentrations with a regression coefficient equal to 0.89. It can be concluded that dietary EPA and DHA can be incorporated in the breeder egg yolk to become available for the developing embryo, without compromising the performance and egg quality of the flock.

Influence of Humic Acid on Stability and Attachment of nTiO2 Particles to Sand at Different pH

NASA Astrophysics Data System (ADS)

Cheng, T.

2015-12-01

Stability of nano-scale or micro-scale titanium dioxide particles (nTiO2) and their attachment to sediment grains have important implications to the fate and transport of nTiO2 in subsurface environments. nTiO2 may carry either positive or negative charges in natural water, therefore, environmental factors such as pH, humic substances, and Fe oxyhydroxide coatings on sediment grains, which are known to control the stability and transport of negatively charged colloids, may influence nTiO2 in different manners. The objective of this study is to investigate the effects of pH and humic acid (HA) on the stability and attachment of nTiO2 to sand, with special attention to low HA concentration ranges that are relevant to groundwater conditions. Stability and attachment of nTiO2 to quartz sand and Fe oxyhydroxide coated quartz sand were experimentally measured under a range of low HA concentrations at pH 5 and 9. Results showed that HA can either promote or hinder nTiO2 stability, depending on pH and HA concentration. We also found that HA can either enhance or reduce nTiO2 attachment to Fe oxyhydroxide coating at pH 5, depending on HA concentration. Results further showed that at pH 5, Fe oxyhydroxide coating reduced nTiO2 attachment to sand in the absence of HA but increased nTiO2 attachment in the presence of low concentration of HA. Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was invoked to analyze particle-to-particle and particle-to-sand interactions in order to elucidate the roles of pH, HA, quartz, and Fe coating in nTiO2 stability and attachment. Overall, this study showed that changes in zeta potential of nTiO2 and Fe coating due to pH changes and/or HA adsorption are the key factors that influence stability and attachment of nTiO2.

Dietary supplementation with very long-chain n-3 fatty acids in man decreases expression of the interleukin-2 receptor (CD25) on mitogen-stimulated lymphocytes from patients with inflammatory skin diseases.

PubMed

Søyland, E; Lea, T; Sandstad, B; Drevon, A

1994-04-01

T-cell activation and cytokine production play an important role in several chronic inflammatory diseases. Because n-3 fatty acids exert beneficial effects on the clinical state of some of these diseases, we examined the effect of dietary supplementation of n-3 fatty acids on T-cell proliferation, expression of CD25 (interleukin-2 receptor alpha-chain), secretion of interleukin-2, interleukin-6 and tumour necrosis factor from T-cells from patients with psoriasis and atopic dermatitis. During 4 months, 21 patients supplied 6 g of highly concentrated ethyl esters of EPA and DHA in gelatin capsules daily to their diet. In the control group 20 patients supplied 6 g per day of corn oil in gelatin capsules to their diet. Eicosapentaenoic acid (20:5, n-3) of serum phospholipids increased from 14 (min 4-max 42) to 81 (min 59-max 144) mg l-1 (P < 0.01) in patients with atopic dermatitis receiving n-3 fatty acids, and from 25 (min 7-max 66) to 74 (min 46-max 142) mg l-1 (P < 0.01) in patients with psoriasis, whereas docosahexaenoic acid (22:6, n-3) increased from 65 (min 46-max 120) to 92 (min 54-max 121) mg l-1 (P < 0.05) and from 81 (min 38-max 122) to 92 (min 63-max 169) mg l-1 (NS) in atopic and psoriatic patients, respectively. The changes in the serum phospholipid fatty acid profile in the groups receiving n-3 fatty acids, correlate to the dietary intake of corresponding fatty acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Physiological role of D-amino acid-N-acetyltransferase of Saccharomyces cerevisiae: detoxification of D-amino acids.

PubMed

Yow, Geok-Yong; Uo, Takuma; Yoshimura, Tohru; Esaki, Nobuyoshi

2006-03-01

Saccharomyces cerevisiae is sensitive to D-amino acids: those corresponding to almost all proteinous L-amino acids inhibit the growth of yeast even at low concentrations (e.g. 0.1 mM). We have determined that D-amino acid-N-acetyltransferase (DNT) of the yeast is involved in the detoxification of D-amino acids on the basis of the following findings. When the DNT gene was disrupted, the resulting mutant was far less tolerant to D-amino acids than the wild type. However, when the gene was overexpressed with a vector plasmid p426Gal1 in the wild type or the mutant S. cerevisiae as a host, the recombinant yeast, which was found to show more than 100 times higher DNT activity than the wild type, was much more tolerant to D-amino acids than the wild type. We further confirmed that, upon cultivation with D-phenylalanine, N-acetyl-D-phenylalanine was accumulated in the culture but not in the wild type and hpa3Delta cells overproducing DNT cells. Thus, D-amino acids are toxic to S. cerevisiae but are detoxified with DNT by N-acetylation preceding removal from yeast cells.

TiO2 activation using acid-treated vermiculite as a support: Characteristics and photoreactivity

NASA Astrophysics Data System (ADS)

Jin, Ling; Dai, Bin

2012-02-01

Vermiculite was treated by sulfuric or nitric acid aqueous solutions with different concentration. These modified materials as the promising supports, were used to immobilize TiO2. TiO2 was prepared by the precursor, which was obtained by substituting partly isopropyl alcohol with Cl- in titanium chloride {[Ti(IV)(OR)nClm] (n = 2-3, m = 4 - n)}. The TiO2/vermiculite composites were characterized by X-ray diffraction, scanning electron microscopy, and the nitrogen absorption. Their photocatalytic activity was evaluated by removal of methylene blue (MB). The pure anatase type crystalline phase was well deposited on the supports. The concentrations of acid for treatment had a significant influence on pore sizes and surface area of vermiculite. The treatment process changed microstructure of vermiculite, modified its characteristics, and farther improved the catalytic activity and absorption capacity of TiO2/vermiculite composites. The treatment effect of nitric acid was superior to that of sulfuric acid.

A 2:1 co-crystal of p-nitro-benzoic acid and N,N'-bis-(pyridin-3-ylmeth-yl)ethanedi-amide: crystal structure and Hirshfeld surface analysis.

PubMed

Syed, Sabrina; Halim, Siti Nadiah Abdul; Jotani, Mukesh M; Tiekink, Edward R T

2016-01-01

The title 2:1 co-crystal, 2C7H5NO4·C14H14N4O2, in which the complete di-amide mol-ecule is generated by crystallographic inversion symmetry, features a three-mol-ecule aggregate sustained by hydroxyl-O-H⋯N(pyrid-yl) hydrogen bonds. The p-nitro-benzoic acid mol-ecule is non-planar, exhibiting twists of both the carb-oxy-lic acid and nitro groups, which form dihedral angles of 10.16 (9) and 4.24 (4)°, respectively, with the benzene ring. The di-amide mol-ecule has a conformation approximating to a Z shape, with the pyridyl rings lying to either side of the central, almost planar di-amide residue (r.m.s. deviation of the eight atoms being 0.025 Å), and forming dihedral angles of 77.22 (6)° with it. In the crystal, three-mol-ecule aggregates are linked into a linear supra-molecular ladder sustained by amide-N-H⋯O(nitro) hydrogen bonds and orientated along [10-4]. The ladders are connected into a double layer via pyridyl- and benzene-C-H⋯O(amide) inter-actions, which, in turn, are connected into a three-dimensional architecture via π-π stacking inter-actions between pyridyl and benzene rings [inter-centroid distance = 3.6947 (8) Å]. An evaluation of the Hirshfeld surfaces confirm the importance of inter-molecular inter-actions involving oxygen atoms as well as the π-π inter-actions.

Food frequency questionnaire as an indicator of the serum composition of essential n-3 and n-6 polyunsaturated fatty acids in early pregnancy, according to body mass index.

PubMed

Lepsch, J; Vaz, J S; Moreira, J D; Pinto, T J P; Soares-Mota, M; Kac, G

2015-02-01

We investigated whether food frequency questionnaire (FFQ) may be indicative of the serum composition of essential n-3 and n-6 polyunsaturated fatty acids (PUFAs) in early pregnancy and if correlations are affected by body mass index (BMI). The present study comprised a prospective cohort conducted in Rio de Janeiro, Brazil. The sample was composed of 248 women, aged 20-40 years, between 6 and the 13 weeks of gestation. Dietary intake was assessed using a validated FFQ. Fatty acid serum compositions were determined in fasting serum samples, employing a high-throughput robotic direct methylation coupled with fast gas-liquid chromatography. Spearman's correlation (r(s)) was used to assess the relationship between fatty acid intake and corresponding serum composition. Women were classified according to BMI (kg m(-2) ) as underweight/normal weight (BMI < 25 kg m(-2) ; n = 139) or excessive weight (BMI ≥ 25 kg m(-2) ; n = 109). In the total sample, dietary report was significantly correlated with the serum composition of total polyunsaturated fatty acid (PUFA; r(s) = 0.232, P < 0.001), linoleic acid (LA; 18:2n-6; r(s) = 0.271, P < 0.001), eicosapentaenoic acid (EPA; 20:5n-3; r(s) = 0.263, P < 0.001) and docosahexaenoic acid (DHA; 22:6n-3; r(s) = 0.209, P = 0.001). When analyses were stratified by BMI, significant correlations between FFQ and serum composition among underweight/normal weight women were observed for total PUFA (r(s) = 0.323, P < 0.001), LA (r(s) = 0.322, P < 0.001), EPA (r(s) = 0.352, P < 0.001) and DHA (r(s) = 0.176, P = 0.039). Among women of excessive weight, significant correlations were observed only for alpha linolenic acid (ALA; 18:3n-3; r(s) = 0.199, P = 0.040) and DHA (r(s) = 0.236, P = 0.014). FFQ in early pregnancy may be used as a possible indicator of serum concentrations of fatty acids. Higher correlations were observed among underweight/normal weight women. © 2014 The British Dietetic Association Ltd.

Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells.

PubMed

Lajczak, Natalia K; Saint-Criq, Vinciane; O'Dwyer, Aoife M; Perino, Alessia; Adorini, Luciano; Schoonjans, Kristina; Keely, Stephen J

2017-09-01

Bile acids and epithelial-derived human β-defensins (HβDs) are known to be important factors in the regulation of colonic mucosal barrier function and inflammation. We hypothesized that bile acids regulate colonic HβD expression and aimed to test this by investigating the effects of deoxycholic acid (DCA) and ursodeoxycholic acid on the expression and release of HβD1 and HβD2 from colonic epithelial cells and mucosal tissues. DCA (10-150 µM) stimulated the release of both HβD1 and HβD2 from epithelial cell monolayers and human colonic mucosal tissue in vitro In contrast, ursodeoxycholic acid (50-200 µM) inhibited both basal and DCA-induced defensin release. Effects of DCA were mimicked by the Takeda GPCR 5 agonist, INT-777 (50 μM), but not by the farnesoid X receptor agonist, GW4064 (10 μM). INT-777 also stimulated colonic HβD1 and HβD2 release from wild-type, but not Takeda GPCR 5 -/- , mice. DCA stimulated phosphorylation of the p65 subunit of NF-κB, an effect that was attenuated by ursodeoxycholic acid, whereas an NF-κB inhibitor, BMS-345541 (25 μM), inhibited DCA-induced HβD2, but not HβD1, release. We conclude that bile acids can differentially regulate colonic epithelial HβD expression and secretion and discuss the implications of our findings for intestinal health and disease.-Lajczak, N. K., Saint-Criq, V., O'Dwyer, A. M., Perino, A., Adorini, L., Schoonjans, K., Keely, S. J. Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells. © FASEB.

Evidence of amino acid precursors: C-N bond coupling in simulated interstellar CO2/NH3 ices

NASA Astrophysics Data System (ADS)

Esmaili, Sasan

2015-08-01

Low energy secondary electrons are abundantly produced in astrophysical or planetary ices by the numerous ionizing radiation fields typically encountered in space environments and may thus play a role in the radiation processing of such ices [1]. One approach to determine their chemical effect is to irradiate nanometer thick molecular solids of simple molecular constituents, with energy selected electron beams and to monitor changes in film chemistry with the surface analytical techniques [2].Of particular interest is the formation of HCN, which is a signature of dense gases in interstellar clouds, and is ubiquitous in the ISM. Moreover, the chemistry of HCN radiolysis products such as CN- may be essential to understand of the formation of amino acids [3] and purine DNA bases. Here we present new results on the irradiation of multilayer films of CO2 and NH3 with 70 eV electrons, leading to CN bond formations. The electron stimulated desorption (ESD) yields of cations and anions are recorded as a function of electron fluence. The prompt desorption of cationic reaction/scattering products [4], is observed at low fluence (~4x1013 electrons/cm2). Detected ions include C2+, C2O2+, C2O+, CO3+, C2O3+ or CO4+ from pure CO2, and N+, NH+, NH2+, NH3+, NH4+, N2+, N2H+ from pure NH3, and NO+, NOH+ from CO2/NH3 mixtures. Most saliently, increasing signals of negative ion products desorbing during prolonged irradiation of CO2/NH3 films included C2-, C2H-, C2H2-, as well as CN-, HCN- and H2CN-. The identification of particular product ions was accomplished by using 13CO2 and 15NH3 isotopes. The chemistry induced by electrons in pure films of CO2 and NH3 and mixtures with composition ratios (3:1), (1:1), and (1:3), was also studied by X-ray photoelectron spectroscopy (XPS). Irradiation of CO2/NH3 mixed films at 22 K produces species containing the following bonds/functional groups identified by XPS: C=O, O-H, C-C, C-O, C=N and N=O. (This work has been funded by NSERC).

Solubility and diffusivity of N{sub 2}O and CO{sub 2} in (diethanolamine + N-methyldiethanolamine + water) and in (diethanolamine + 2-amino-2-methyl-1-propanol + water)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, M.H.; Lee, W.C.

1996-05-01

Acid gases such as CO{sub 2} and H{sub 2}S are frequently removed from natural gas, synthetic natural gas, and other process gas streams by means of absorption into aqueous alkanol-amine solutions. The solubility and diffusivity of N{sub 2}O in (diethanolamine + N-methyldiethanolamine + water) and in (diethanolamine + 2-amino-2-methyl-1-propanol + water) were measured at (30, 35, and 40)C and at atmospheric pressure. Five (diethanolamine + N-methyldiethanolamine + water) and four (diethanolamine + 2-amino-2-methyl-1-propanol + water) systems were studied. The total amine mass percent in all cases was 30. A solubility apparatus was used to measure the solubility of N{sub 2}Omore » in amine solutions. The diffusivity was measured by a wetted wall column absorber. The N{sub 2}O analogy was used to estimate the solubility and diffusivity of CO{sub 2} in (diethanolamine + N-methyldiethanolamine + water) and in (diethanolamine + 2-amino-2-methyl-1-propanol + water).« less

Supra-molecular architecture in a co-crystal of the N(7)-H tautomeric form of N (6)-benzoyl-adenine with adipic acid (1/0.5).

PubMed

Swinton Darious, Robert; Thomas Muthiah, Packianathan; Perdih, Franc

2016-06-01

The asymmetric unit of the title co-crystal, C12H9N5O·0.5C6H10O4, consists of one mol-ecule of N (6)-benzoyl-adenine (BA) and one half-mol-ecule of adipic acid (AA), the other half being generated by inversion symmetry. The dihedral angle between the adenine and phenyl ring planes is 26.71 (7)°. The N (6)-benzoyl-adenine mol-ecule crystallizes in the N(7)-H tautomeric form with three non-protonated N atoms. This tautomeric form is stabilized by intra-molecular N-H⋯O hydrogen bonding between the carbonyl (C=O) group and the N(7)-H hydrogen atom on the Hoogsteen face of the purine ring, forming an S(7) ring motif. The two carboxyl groups of adipic acid inter-act with the Watson-Crick face of the BA mol-ecules through O-H⋯N and N-H⋯O hydrogen bonds, generating an R 2 (2)(8) ring motif. The latter units are linked by N-H⋯N hydrogen bonds, forming layers parallel to (10-5). A weak C-H⋯O hydrogen bond is also present, linking adipic acid mol-ecules in neighbouring layers, enclosing R (2) 2(10) ring motifs and forming a three-dimensional structure. C=O⋯π and C-H⋯π inter-actions are also present in the structure.

Cholic acid modified N-(2-hydroxy)-propyl-3-trimethylammonium chitosan chloride for superoxide dismutase delivery.

PubMed

Cheng, Ye; Cai, Huanxin; Yin, Baoru; Yao, Ping

2013-09-15

A series of novel amphiphilic chitosan derivatives, cholic acid modified N-(2-hydroxy)-propyl-3-trimethylammonium chitosan chloride (HTCC-CA) with different quaternization degrees and cholic acid substitutions were synthesized in this study. HTCC-CA is biocompatible and forms particles in aqueous solution. The binding with superoxide dismutase (SOD) at pH 6.8 destroys the original aggregates of HTCC-CA and produces smaller SOD/HTCC-CA complex nanoparticles via electrostatic and hydrophobic interactions. The SOD loading efficiency and loading capacity of HTCC-CA can reach to more than 90% and 45%, respectively. Confocal laser scanning microscopy observation and flow cytometry analysis reveal that SOD/HTCC-CA complex nanoparticles greatly enhance the cellular internalization of the loaded SOD. The SOD activities and malonaldehyde concentrations in the serum and organs of the rats, administrated intravenously with free SOD, free HTCC-CA, and SOD/HTCC-CA nanoparticles, were assayed to evaluate the antioxidant efficiency in vivo. The results demonstrate that free HTCC-CA is effective to scavenge superoxide radicals in the blood circulation and SOD/HTCC-CA nanoparticles have better antioxidant efficiency than free SOD as well as free HTCC-CA. Copyright © 2013 Elsevier B.V. All rights reserved.

Quantification of N-acetyl- and N-glycolylneuraminic acids by a stable isotope dilution assay using high-performance liquid chromatography-tandem mass spectrometry.

PubMed

Allevi, Pietro; Femia, Eti Alessandra; Costa, Maria Letizia; Cazzola, Roberta; Anastasia, Mario

2008-11-28

The present report describes a method for the quantification of N-acetyl- and N-glycolylneuraminic acids without any derivatization, using their (13)C(3)-isotopologues as internal standards and a C(18) reversed-phase column modified by decylboronic acid which allows for the first time a complete chromatographic separation between the two analytes. The method is based on high-performance liquid chromatographic coupled with electrospray ion-trap mass spectrometry. The limit of quantification of the method is 0.1mg/L (2.0ng on column) for both analytes. The calibration curves are linear for both sialic acids over the range of 0.1-80mg/L (2.0-1600ng on column) with a correlation coefficient greater than 0.997. The proposed method was applied to the quantitative determination of sialic acids released from fetuin as a model of glycoproteins.

Return of the lysergamides. Part II: Analytical and behavioural characterization of N6-allyl-6-norlysergic acid diethylamide (AL-LAD) and (2’S,4’S)-lysergic acid 2,4-dimethylazetidide (LSZ)

PubMed Central

Brandt, Simon D.; Kavanagh, Pierce V.; Westphal, Folker; Elliott, Simon P.; Wallach, Jason; Colestock, Tristan; Burrow, Timothy E.; Chapman, Stephen J.; Stratford, Alexander; Nichols, David E.; Halberstadt, Adam L.

2017-01-01

Lysergic N,N-diethylamide (LSD) is perhaps one of the most intriguing psychoactive substances known and numerous analogs have been explored to a varying extent in previous decades. In 2013, N6-allyl-6-norlysergic acid diethylamide (AL-LAD) and (2’S,4’S)-lysergic acid 2,4-dimethylazetidide (LSZ) have appeared on the ‘research chemicals’ / new psychoactive substances (NPS) market in both powdered and blotter form. This study reports the analytical characterization of powdered AL-LAD and LSZ tartrate samples and their semi-quantitative determination on blotter paper. Included in this study was the use of nuclear magnetic resonance spectroscopy, gas chromatography mass spectrometry (MS), low and high-resolution electrospray MS(/MS), high performance liquid chromatography diode array detection and GC solid-state infrared analysis. One feature shared by serotonergic psychedelics, such as LSD, is the ability to mediate behavioral responses via activation of 5-HT2A receptors. Both AL-LAD and LSZ displayed LSD-like responses in male C57BL/6J mice when employing the head-twitch response (HTR) assay. AL-LAD and LSZ produced nearly identical inverted-U-shaped dose-dependent effects, with the maximal responses occurring at 200 µg/kg. Analysis of the dose-responses by nonlinear regression confirmed that LSZ (ED50 = 114.2 nmol/kg) was equipotent to LSD (ED50 = 132.8 nmol/kg) in mice, whereas AL-LAD was slightly less potent (ED50 = 174.9 nmol/kg). The extent to which a comparison in potency can be translated directly to humans requires further investigation. Availability of both chemical and pharmacological data obtained from NPS as they appear on the market provides important data to research communities that are interested in various aspects related substance use and forensic identification. PMID:27265891

Reevaluation of the effect of ellagic acid on N-methyl-N-nitrosourea DNA alkylation and mutagenicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lord, H.L.; Josephy, P.D.; Snieckus, V.A.

N-Methyl-N-nitrosourea (MNU) is a reactive, mutagenic methylating agent. MNU methylates DNA at various sites, including guanine N{sup 7}, guanine O{sup 6}, and adenine N{sup 3}. Dixit and Gold ((1986) Proc. Natl, Acad. Sci. U.S.A. 83, 8039-8043) reported that ellagic acid, a phenolic natural product, inhibited the mutagenicity of MNU in Salmonella typhimurium strain TA 100, inhibited salmon sperm DNA alkylation by ({sup 3}H)MNU, and also greatly reduced the ratio of guanine O{sup 6} to guanine N{sup 7} alkylation. We have examined the MNU-induced alkylation of calf thymus DNA and evaluated the effect of ellagic acid on this binding. Ellagic acidmore » had only a slight effect on total alkylation and did not alter the ratio of methylation at guanine-O{sup 6} and -N{sup 7} positions. In further experiments, ellagic acid did not significantly inhibit MNU mutagenicity. These findings do not support the potential use of ellagic acid as an inhibitor of biological damage induced by nitrosoureas.« less

Association between very long chain fatty acids in the meibomian gland and dry eye resulting from n-3 fatty acid deficiency.

PubMed

Tanaka, Hideko; Harauma, Akiko; Takimoto, Mao; Moriguchi, Toru

2015-06-01

In our previously study, we reported lower tear volume in with an n-3 fatty acid deficient mice and that the docosahexaenoic acid and total n-3 fatty acid levels in these mice are significantly reduced in the meibomian gland, which secretes an oily tear product. Furthermore, we noted very long chain fatty acids (≥25 carbons) in the meibomian gland. To verify the detailed mechanism of the low tear volume in the n-3 fatty acid-deficient mice, we identified the very long chain fatty acids in the meibomian gland, measured the fatty acid composition in the tear product. Very long chain fatty acids were found to exist as monoesters. In particular, very long chain fatty acids with 25-29 carbons existed for the most part as iso or anteiso branched-chain fatty acids. n-3 fatty acid deficiency was decreased the amount of meibum secretion from meibomian gland without change of fatty acid composition. These results suggest that the n-3 fatty acid deficiency causes the enhancement of evaporation of tear film by reducing oily tear secretion along with the decrease of meibomian gland function. Copyright © 2015 Elsevier Ltd. All rights reserved.

R(-)-4-(3-Isothiocyanatopyrrolidin-1-yl)-7-(N,N-dimethylaminosulfonyl)-2,1,3-benzoxadiazole, a fluorescent chiral tagging reagent: sensitive resolution of chiral amines and amino acids by reversed-phase liquid chromatography.

PubMed

Toyo'oka, T; Jin, D; Tomoi, N; Oe, T; Hiranuma, H

2001-02-01

The usefulness of R(-)-4-(3-isothiocyanatopyrrolidin-1-yl)-7-(N,N-dimethylaminosulfonyl)-2,1,3-benzoxadiazole [R(-)-DBD-PyNCS], a fluorescent chiral tagging reagent, for the determination of racemic amines and amino acids, was studied. The reagent reacted with beta-blockers selected as representative secondary amines to produce corresponding fluorescent diastereomers (excitation at 460 nm and emission at 550 nm). The yields of the derivatization reaction were dependent on the stereostructure arround the NH group in beta-blockers. The resulting diastereomers were completely separated with single chromatographic run using linear gradient elutions by reversed-phase chromatography. R(-)-DBD-PyNCS was also applied to the determination of DL-amino acid, considered to be one of the primary amines, in human urine and foodstuffs. DL-amino acids tested equally reacted with the reagent, and the thiocarbamoyl derivatives were separated with an ODS column. The epimerization during the derivatization reaction was negligible judging from the resolution of opposite diastereomers on the chromatogram. The occurence of D-amino acids (D-Ala, D-Ser, D-Asp and/or D-Glu) was identified in the samples tested. The structures and the purities were elucidated with on-line HPLC-MS. The chiral reagent possessing an isothiocyanate group (-NCS) in the structure seems to be applicable to continuous sequential analysis of peptides containing D-amino acids. The thiocarbamoyl derivatives obtained from the reaction with DL-amino acids were converted to thiohydantoins via thiazolinones in acidic medium. The thiohydantoins produced from acidic, basic, neutral, hydroxyl and aromatic amino acids were completely separated with isocratic elutions using acidic mobile phase containing 0.1% TFA. The separations were sufficient for the identification of DL-amino acid in peptide sequences. Although the epimerization during the conversion reaction to thiohydantoins was not avoidable, the descrimination of D- and

α-lipoic acid ameliorates n-3 highly-unsaturated fatty acids induced lipid peroxidation via regulating antioxidant defenses in grass carp (Ctenopharyngodon idellus).

PubMed

Shi, Xiao-Chen; Jin, Ai; Sun, Jian; Yang, Zhou; Tian, Jing-Jing; Ji, Hong; Yu, Hai-Bo; Li, Yang; Zhou, Ji-Shu; Du, Zhen-Yu; Chen, Li-Qiao

2017-08-01

This study evaluated the protective effect of α-lipoic acid (LA) on n-3 highly unsaturated fatty acids (HUFAs)-induced lipid peroxidation in grass carp. The result indicated that diets with n-3 HUFAs increased the production of malondialdehyde (MDA) (P < 0.05), thereby inducing lipid peroxidation in liver and muscle of grass carp. Meanwhile, compared with control group, the hepatosomatic index (HSI) and kidney index (KI) of grass carp were markedly increased in n-3 HUFAs-only group. However, diets with LA remarkably inhibited the n-3 HUFAs-induced increase of HSI, KI, and MDA level in serum, liver and muscle (P < 0.05). Interestingly, LA also significantly elevated the ratio of total n-3 HUFAs in fatty acid composition of muscle and liver (P < 0.05). Furthermore, LA significantly promoted the activity of antioxidant enzymes in serum, muscle and liver of grass carp (P < 0.05), including superoxide dismutase (SOD), catalase (CAT), and glutathione s-transferase (GST). The further results showed that LA significantly elevated mRNA expression of antioxidant enzymes with promoting the mRNA expression of NF-E2-related nuclear factor 2 (Nrf2) and decreasing Kelch-like-ECH-associated protein 1 (Keap1) mRNA level. From the above, these results suggested that LA could attenuate n-3 HUFAs-induced lipid peroxidation, remit the toxicity of the lipid peroxidant, and protect n-3 HUFAs against lipid peroxidation to promote its deposition in fish, likely strengthening the activity of antioxidant enzymes through regulating mRNA expressions of antioxidant enzyme genes via mediating Nrf2-Keap1 signaling pathways. Copyright © 2017 Elsevier Ltd. All rights reserved.

n-3 Fatty Acids Attenuate the Risk of Diabetes Associated With Elevated Serum Nonesterified Fatty Acids: The Multi-Ethnic Study of Atherosclerosis

PubMed Central

Steffen, Brian T.; Steffen, Lyn M.; Zhou, Xia; Ouyang, Pamela; Weir, Natalie L.

2015-01-01

OBJECTIVE Chronically high nonesterified fatty acids (NEFAs) are a marker of metabolic dysfunction and likely increase risk of type 2 diabetes. By comparison, n-3 fatty acids (FAs) have been shown to have various health benefits and may protect against disease development. In 5,697 participants of the Multi-Ethnic Study of Atherosclerosis (MESA), we examined whether serum levels of NEFAs relate to risk of incident type 2 diabetes and further tested whether plasma n-3 FA levels may interact with this relation. RESEARCH DESIGN AND METHODS NEFAs were measured in fasting serum using an enzymatic colorimetric assay and phospholipid n-3 FAs eicosapentaenoic and docosahexaenoic acids were determined in plasma through gas chromatography-flame ionization detection in 5,697 MESA participants. Cox proportional hazards regression evaluated the association between NEFA levels and incident type 2 diabetes and whether plasma n-3 FAs modified this association adjusting for age, sex, race, education, field center, smoking, and alcohol use. RESULTS Over a mean 11.4 years of the study period, higher diabetes incidence was found across successive NEFA quartiles (Q) (hazard ratio [95% CI]): Q1, 1.0; Q2, 1.35 (1.07, 1.71); Q3, 1.58 (1.24, 2.00); and Q4, 1.86 (1.45, 2.38) (Ptrend < 0.001). A significant interaction of n-3 FAs on the relation between NEFAs and type 2 diabetes was also observed (Pinteraction = 0.03). For individuals with lower n-3 levels (<75th percentile), a higher risk of type 2 diabetes was observed across quartiles of NEFAs: Q1, 1.0; Q2, 1.41 (1.07, 1.84); Q3, 1.77 (1.35, 2.31); and Q4, 2.18 (1.65, 2.88) (Ptrend < 0.001). No significant associations were observed in those with n-3 FAs ≥75th percentile (Ptrend = 0.54). CONCLUSIONS NEFAs are a marker of type 2 diabetes and may have clinical utility for detecting risk of its development. The modifying influence of n-3 FAs suggests a protective effect against disease and/or metabolic dysfunction related to NEFAs and

Synthesis of structured triacylglycerols enriched in n-3 fatty acids by immobilized microbial lipase.

PubMed

Araújo, Maria Elisa Melo Branco de; Campos, Paula Renata Bueno; Alberto, Thiago Grando; Contesini, Fabiano Jares; Carvalho, Patrícia de Oliveira

The search for new biocatalysts has aroused great interest due to the variety of micro-organisms and their role as enzyme producers. Native lipases from Aspergillus niger and Rhizopus javanicus were used to enrich the n-3 long-chain polyunsaturated fatty acids content in the triacylglycerols of soybean oil by acidolysis with free fatty acids from sardine oil in solvent-free media. For the immobilization process, the best lipase/support ratios were 1:3 (w/w) for Aspergillus niger lipase and 1:5 (w/w) for Rhizopus javanicus lipase using Amberlite MB-1. Both lipases maintained constant activity for 6 months at 4°C. Reaction time, sardine-free fatty acids:soybean oil mole ratio and initial water content of the lipase were investigated to determine their effects on n-3 long-chain polyunsaturated fatty acids incorporation into soybean oil. Structured triacylglycerols with 11.7 and 7.2% of eicosapentaenoic acid+docosahexaenoic acid were obtained using Aspergillus niger lipase and Rhizopus javanicus lipase, decreasing the n-6/n-3 fatty acids ratio of soybean oil (11:1 to 3.5:1 and 4.7:1, respectively). The best reaction conditions were: initial water content of lipase of 0.86% (w/w), sardine-free faty acids:soybean oil mole ratio of 3:1 and reaction time of 36h, at 40°C. The significant factors for the acidolysis reaction were the sardine-free fatty acids:soybean oil mole ratio and reaction time. The characterization of structured triacylglycerols was obtained using easy ambient sonic-spray ionization mass spectrometry. The enzymatic reaction led to the formation of many structured triacylglycerols containing eicosapentaenoic acid, docosahexaenoic acid or both polyunsaturated fatty acids. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Mead acid (20:3n-9) and n-3 polyunsaturated fatty acids are not associated with risk of posterior longitudinal ligament ossification: results of a case-control study.

PubMed

Hamazaki, Kei; Kawaguchi, Yoshiharu; Nakano, Masato; Yasuda, Taketoshi; Seki, Shoji; Hori, Takeshi; Hamazaki, Tomohito; Kimura, Tomoatsu

2015-05-01

Ossification of the posterior longitudinal ligament (OPLL) involves the replacement of ligamentous tissue with ectopic bone. Although genetics and heritability appear to be involved in the development of OPLL, its pathogenesis remains to be elucidated. Given previous findings that 5,8,11-eicosatrienoic acid [20:3n-9, Mead acid (MA)] has depressive effects on osteoblastic activity and anti-angiogenic effects, and that n-3 polyunsaturated fatty acids (PUFAs) have a preventive effect on heterotopic ossification, we hypothesized that both fatty acids would be involved in OPLL development. To examine the biological significance of these and other fatty acids in OPLL, we conducted this case-control study involving 106 patients with cervical OPLL and 109 age matched controls. Fatty acid composition was determined from plasma samples by gas chromatography. Associations between fatty acid levels and incident OPLL were evaluated by logistic regression. Contrary to our expectations, we found no significant differences between patients and controls in the levels of MA or n-3 PUFAs (e.g., eicosapentaenoic acid and docosahexaenoic acid). Logistic regression analysis did not reveal any associations with OPLL risk for MA or n-3 PUFAs. In conclusion, no potential role was found for MA or n-3 PUFAs in ectopic bone formation in the spinal canal. Copyright © 2015 Elsevier Ltd. All rights reserved.

Low n-6:n-3 fatty acid ratio, with fish- or flaxseed oil, in a high fat diet improves plasma lipids and beneficially alters tissue fatty acid composition in mice.

PubMed

Riediger, Natalie D; Othman, Rgia; Fitz, Evelyn; Pierce, Grant N; Suh, Miyoung; Moghadasian, Mohammed H

2008-04-01

Health benefits from low n-6:n-3 fatty acid (FA) ratio on cardiovascular risk have been shown. However, the impact of the source of n-3 FAs has not been fully investigated. Our purpose was to investigate cardiovascular benefits of oils with a low ratio of n-6:n-3 FAs, but different sources of n-3 FAs in C57BL/6 mice. Twenty-one mice were divided into 3 groups (n=7) and fed a diet supplemented with either a fish or flaxseed oil-based 'designer oils' with an approximate n-6:n-3 FA ratio of 2/1 or with a safflower-oil-based diet with a ratio of 25/1, for 16 weeks. Plasma lipids and fatty acid profile of the liver tissue were characterized. Compared to baseline, plasma triacylglycerol levels declined (>50%) in all groups by week 4. Plasma cholesterol levels were reduced in both fish and flax groups by 27% and 36%, respectively, as compared to controls at endpoint. The levels of EPA and DHA in liver phospholipids were significantly increased in both fish and flax groups as compared to the control group, with more profound increases in the fish group. Arachidonic acid levels were similarly decreased in the liver tissues from both fish and flax groups as compared to controls. Our data suggest that health benefits may be achieved by lowering dietary n-6:n-3 FA even in a high fat diet medium.

Immunohistochemical detection of a substituted 1,N(2)-ethenodeoxyguanosine adduct by omega-6 polyunsaturated fatty acid hydroperoxides in the liver of rats fed a choline-deficient, L-amino acid-defined diet.

PubMed

Kawai, Yoshichika; Kato, Yoji; Nakae, Dai; Kusuoka, Osamu; Konishi, Yoichi; Uchida, Koji; Osawa, Toshihiko

2002-03-01

Endogenous lipid peroxidation products react with DNA and form exocyclic DNA adducts. The purpose of this study was to investigate the in vivo formation of 7-(2-oxo-heptyl)-substituted 1,N(2)-etheno-2'-deoxyguanosine adduct (Oxo-heptyl-varepsilondG), one of the major products from the reaction of 13-hydroperoxyoctadecadienoic acid (13-HPODE) with dG. The monoclonal antibody specific to Oxo-heptyl-varepsilondG was prepared using a chemically synthesized conjugate of Oxo-heptyl-varepsilondG and carrier protein as immunogen. The characterization showed that the obtained antibody (mAb6A3) is specific to the Oxo-heptyl-varepsilondG moiety. Using the novel antibody, the presence of the Oxo-heptyl-varepsilondG adduct in vivo was immunohistochemically revealed in the liver of rats fed a choline-deficient, L-amino acid-defined diet, an endogenous carcinogenesis model, for 3 days. In addition, the Oxo-heptyl-varepsilondG formation was confirmed in DNAs treated with peroxidized linoleic acid, arachidonic acid and gamma-linolenic acid, respectively, suggesting that the hydroperoxides of omega-6 polyunsaturated fatty acids could be the potential sources of Oxo-heptyl-varepsilondG formation in vivo. Collectively, the results in this study suggest the first evidence that the formation of Oxo-heptyl-varepsilondG, the omega-6 lipid hydroperoxide-mediated DNA adduct, may be a potential biomarker for the early phase of carcinogenesis.

n-3 fatty acids: role in neurogenesis and neuroplasticity.

PubMed

Crupi, R; Marino, A; Cuzzocrea, S

2013-01-01

Omega-3 polyunsaturated fatty acids (PUFA) are essential unsaturated fatty acids with a double bond (C=C) starting after the third carbon atom from the end of the carbon chain. They are important nutrients but, unfortunately, mammals cannot synthesize them, whereby they must be obtained from food sources or from supplements. Amongst nutritionally important polyunsaturated n-3 fatty acids, α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are highly concentrated in the brain and have anti-oxidative stress, anti-inflammatory and antiapoptotic effects. They are involved in many bodily processes and may reportedly lead to neuron protection in neurological diseases. aged or damaged neurons and in Alzheimer's disease. Their effect in cognitive and behavioral functions and in several neurological and psychiatric disorders has been also proven. The dentate gyrus (DG), a sub-region of hippocampus, is implicated in cognition and mood regulation. The hippocampus represents one of the two areas in the mammalian brain in which adult neurogenesis occurs. This process is associated with beneficial effects on cognition, mood and chronic pharmacological treatment. The exposure to n-3 fatty acids enhances adult hippocampal neurogenesis associated with cognitive and behavioral processes, promotes synaptic plasticity by increasing long-term potentiation and modulates synaptic protein expression to stimulate the dendritic arborization and new spines formation. On this basis we review the effect of n-3 fatty acids on adult hippocampal neurogenesis and neuroplasticity. Moreover their possible use as a new therapeutic approach for neurodegenerative diseases is pointed out.

Comparison of Nitrilotriacetic Acid and [S,S]-Ethylenediamine-N,N'-disuccinic Acid in UV-Fenton for the Treatment of Oil Sands Process-Affected Water at Natural pH.

PubMed

Zhang, Ying; Klamerth, Nikolaus; Chelme-Ayala, Pamela; Gamal El-Din, Mohamed

2016-10-04

The application of UV-Fenton processes with two chelating agents, nitrilotriacetic acid (NTA) and [S,S]-ethylenediamine-N,N'-disuccinic acid ([S,S]-EDDS), for the treatment of oil sands process-affected water (OSPW) at natural pH was investigated. The half-wave potentials of Fe(III/II)NTA and Fe(III/II)EDDS and the UV photolysis of the complexes in Milli-Q water and OSPW were compared. Under optimum conditions, UV-NTA-Fenton exhibited higher efficiency than UV-EDDS-Fenton in the removal of acid extractable organic fraction (66.8% for the former and 50.0% for the latter) and aromatics (93.5% for the former and 74.2% for the latter). Naphthenic acids (NAs) removals in the UV-NTA-Fenton process (98.4%, 86.0%, and 81.0% for classical NAs, NAs + O (oxidized NAs with one additional oxygen atom), and NAs + 2O (oxidized NAs with two additional oxygen atoms), respectively) under the experimental conditions were much higher than those in the UV-H 2 O 2 (88.9%, 48.7%, and 54.6%, correspondingly) and NTA-Fenton (69.6%, 35.3%, and 44.2%, correspondingly) processes. Both UV-NTA-Fenton and UV-EDDS-Fenton processes presented promoting effect on the acute toxicity of OSPW toward Vibrio fischeri. No significant change of the NTA toxicity occurred during the photolysis of Fe(III)NTA; however, the acute toxicity of EDDS increased as the photolysis of Fe(III)EDDS proceeded. NTA is a much better agent than EDDS for the application of UV-Fenton process in the treatment of OSPW.

Control of C/N ratio for butyric acid production from textile wastewater sludge by anaerobic digestion.

PubMed

Fu, Bo; Zhang, Jingjing; Fan, Jinfeng; Wang, Jin; Liu, He

2012-01-01

Increasing textile wastewaters and their biotreatment byproduct-waste activated sludge are serious pollution problems. Butyric acid production from textile wastewater sludge by anaerobic digestion at different C/N ratios was investigated. Adding starch to textile wastewater sludge with a C/N ratio of 30 increased the butyric acid concentration and percentage accounting for total volatile fatty acids (TVFAs) to 21.42 g/L and 81.5%, respectively, as compared with 21.42 g/L and 10.6% of textile wastewater sludge alone. The maximum butyric acid yield (0.45 g/g VS), conversion rate (0.74 g/g VS(digest)) and production rate (2.25 g/L d) was achieved at a C/N ratio of 30. The biological toxicity of textile wastewater sludge also significantly decreased after the anaerobic digestion. The study indicated that the anaerobic co-digestion of textile wastewater sludge and carbohydrate-rich waste with appropriate C/N ratio is possible for butyric acid production.

15N Abundance of Nodules as an Indicator of N Metabolism in N2-Fixing Plants 1

PubMed Central

Shearer, Georgia; Feldman, Lori; Bryan, Barbara A.; Skeeters, Jerri L.; Kohl, Daniel H.; Amarger, Nöelle; Mariotti, Françoise; Mariotti, André

1982-01-01

This paper expands upon previous reports of 15N elevation in nodules (compared to other tissues) of N2-fixing plants. N2-Fixing nodules of Glycine max (soybeans), Vigna unguiculata (cowpea), Phaseolus vulgaris (common bean), Phaseolus coccineus (scarlet runner bean), Prosopis glandulosa (mesquite), and Olneya tesota (desert ironwood) were enriched in 15N. Nodules of Vicia faba (fava beans), Arachis hypogaea (peanut), Trifolium pratense (red clover), Pisum sativum (pea), Lathyrus sativus (grass pea), Medicago sativa (alfalfa), and Lupinus mutabilis (South American lupine) were not; nor were the nodules of nine species of N2-fixing nonlegumes. The nitrogen of ineffective nodules of soybeans and cowpeas was not enriched in 15N. Thus, 15N elevation in nodules of these plants depends on active N2-fixation. Results obtained so far on the generality of 15N enrichment in N2-fixing nodules suggest that only the nodules of plants which actively fix N2 and which transport allantoin or allantoic acid exhibit 15N enrichment. PMID:16662517

Ab initio studies on Al(+)(H(2)O)(n), HAlOH(+)(H(2)O)(n-1), and the size-dependent H(2) elimination reaction.

PubMed

Siu, Chi-Kit; Liu, Zhi-Feng; Tse, John S

2002-09-11

We report computational studies on Al(+)(H(2)O)(n), and HAlOH(+)(H(2)O)(n-1), n = 6-14, by the density functional theory based ab initio molecular dynamics method, employing a planewave basis set with pseudopotentials, and also by conventional methods with Gaussian basis sets. The mechanism for the intracluster H(2) elimination reaction is explored. First, a new size-dependent insertion reaction for the transformation of Al(+)(H(2)O)(n), into HAlOH(+)(H(2)O)(n-1) is discovered for n > or = 8. This is because of the presence of a fairly stable six-water-ring structure in Al(+)(H(2)O)(n) with 12 members, including the Al(+). This structure promotes acidic dissociation and, for n > or = 8, leads to the insertion reaction. Gaussian based BPW91 and MP2 calculations with 6-31G* and 6-31G** basis sets confirmed the existence of such structures and located the transition structures for the insertion reaction. The calculated transition barrier is 10.0 kcal/mol for n = 9 and 7.1 kcal/mol for n = 8 at the MP2/6-31G** level, with zero-point energy corrections. Second, the experimentally observed size-dependent H(2) elimination reaction is related to the conformation of HAlOH(+)(H(2)O)(n-1), instead of Al(+)(H(2)O)(n). As n increases from 6 to 14, the structure of the HAlOH(+)(H(2)O)(n-1) cluster changes into a caged structure, with the Al-H bond buried inside, and protons produced in acidic dissociation could then travel through the H(2)O network to the vicinity of the Al-H bond and react with the hydride H to produce H(2). The structural transformation is completed at n = 13, coincident approximately with the onset of the H(2) elimination reaction. From constrained ab initio MD simulations, we estimated the free energy barrier for the H(2) elimination reaction to be 0.7 eV (16 kcal/mol) at n = 13, 1.5 eV (35 kcal/mol) at n = 12, and 4.5 eV (100 kcal/mol) at n = 8. The existence of transition structures for the H(2) elimination has also been verified by ab initio calculations

The role of the acidity of N-heteroaryl sulfonamides as inhibitors of bcl-2 family protein-protein interactions.

PubMed

Touré, B Barry; Miller-Moslin, Karen; Yusuff, Naeem; Perez, Lawrence; Doré, Michael; Joud, Carol; Michael, Walter; DiPietro, Lucian; van der Plas, Simon; McEwan, Michael; Lenoir, Francois; Hoe, Madelene; Karki, Rajesh; Springer, Clayton; Sullivan, John; Levine, Kymberly; Fiorilla, Catherine; Xie, Xiaoling; Kulathila, Raviraj; Herlihy, Kara; Porter, Dale; Visser, Michael

2013-02-14

Overexpression of the antiapoptotic members of the Bcl-2 family of proteins is commonly associated with cancer cell survival and resistance to chemotherapeutics. Here, we describe the structure-based optimization of a series of N-heteroaryl sulfonamides that demonstrate potent mechanism-based cell death. The role of the acidic nature of the sulfonamide moiety as it relates to potency, solubility, and clearance is examined. This has led to the discovery of novel heterocyclic replacements for the acylsulfonamide core of ABT-737 and ABT-263.

The Role of the Acidity of N-Heteroaryl Sulfonamides as Inhibitors of Bcl-2 Family Protein–Protein Interactions

PubMed Central

2013-01-01

Overexpression of the antiapoptotic members of the Bcl-2 family of proteins is commonly associated with cancer cell survival and resistance to chemotherapeutics. Here, we describe the structure-based optimization of a series of N-heteroaryl sulfonamides that demonstrate potent mechanism-based cell death. The role of the acidic nature of the sulfonamide moiety as it relates to potency, solubility, and clearance is examined. This has led to the discovery of novel heterocyclic replacements for the acylsulfonamide core of ABT-737 and ABT-263. PMID:24900652

Critical current densities in superconducting Y-Ba-Cu-O prepared by chelating method

NASA Astrophysics Data System (ADS)

Fujisawa, Tadashi; Okuyama, Katsuro; Ohshima, Shigetoshi; Takagi, Akira

1990-10-01

The IDA, NTA, HEDTA, EDTA, TTHA, and DTPA chelating agents have been used to prepare the Y-Ba-Cu-O compounds whose critical current is presently investigated. It is noted that the precursor YBCO prepared from large stability-constant metal complexes (HEDTA, EDTA, DTPA, and TTHA) exhibited very fine and homogeneous particles. The critical current density of a 1 x 4 x 15 mm block of YBCO sintered at 880-910 C for 24 h and subsequently annealed at 500 C in an O2 flow was approximately 500 A/sq cm at 77 K, in zero magnetic field.

Serum n-6 and n-9 Fatty Acids Correlate With Serum IGF-1 and Growth Up to 4 Months of Age in Healthy Infants.

PubMed

Kjellberg, Emma; Roswall, Josefine; Bergman, Stefan; Strandvik, Birgitta; Dahlgren, Jovanna

2018-01-01

The aim of this study was to study the relationship between insulin-like growth factor-1 (IGF-1), serum phospholipid fatty acids, and growth in healthy full-term newborns during infancy. Prospective observational study of a population-based Swedish cohort comprising 126 healthy, term infants investigating cord blood and serum at 2 days and 4 months of age for IGF-1 and phospholipid fatty acid profile and breast milk for fatty acids at 2 days and 4 months, compared with anthropometric measurements (standard deviation scores). At all time-points arachidonic acid (AA) was negatively associated with IGF-1. IGF-1 had positive associations with linoleic acid (LA) at 2 days and 4 months and mead acid (MA) showed positive associations in cord blood. Multiple regression analyses adjusted for maternal factors (body mass index, weight gain, smoking, education), sex, birth weight and feeding modality confirmed a negative association for the ratio AA/LA to IGF-1. MA in cord blood correlated to birth size. Changes in the ratios of n-6/n-3 and AA/docosahexaenoic acid from day 2 to 4 months together with infants' weight and feeding modality determined 55% of the variability of delta-IGF-1. Breast-fed infants at 4 months had lower IGF-1 correlating with lower LA and higher AA concentrations, which in girls correlated with lower weight gain from birth to 4 months of age. Our data showed interaction of n-6 fatty acids with IGF-1 during the first 4 months of life, and an association between MA and birth size when adjusted for confounding factors. Further follow-up may indicate whether these correlations are associated with later body composition.

Aminomethylation of enals through carbene and acid cooperative catalysis: concise access to β(2)-amino acids.

PubMed

Xu, Jianfeng; Chen, Xingkuan; Wang, Ming; Zheng, Pengcheng; Song, Bao-An; Chi, Yonggui Robin

2015-04-20

A convergent, organocatalytic asymmetric aminomethylation of α,β-unsaturated aldehydes by N-heterocyclic carbene (NHC) and (in situ generated) Brønsted acid cooperative catalysis is disclosed. The catalytically generated conjugated acid from the base plays dual roles in promoting the formation of azolium enolate intermediate, formaldehyde-derived iminium ion (as an electrophilic reactant), and methanol (as a nucleophilic reactant). This redox-neutral strategy is suitable for the scalable synthesis of enantiomerically enriched β(2) -amino acids bearing various substituents. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A novel sodium N-fatty acyl amino acid surfactant using silkworm pupae as stock material

PubMed Central

Wu, Min-Hui; Wan, Liang-Ze; Zhang, Yu-Qing

2014-01-01

A novel sodium N-fatty acyl amino acid (SFAAA) surfactant was synthesized using pupa oil and pupa protein hydrolysates (PPH) from a waste product of the silk industry. The aliphatic acids from pupa oil were modified into N-fatty acyl chlorides by thionyl chloride (SOCl2). SFAAA was synthesized using acyl chlorides and PPH. GC-MS analysis showed fatty acids from pupa oil consist mainly of unsaturated linolenic and linoleic acids and saturated palmitic and stearic acids. SFAAA had a low critical micelle concentration, great efficiency in lowering surface tension and strong adsorption at an air/water interface. SFAAA had a high emulsifying power, as well as a high foaming power. The emulsifying power of PPH and SFAAA in an oil/water emulsion was better with ethyl acetate as the oil phase compared to n-hexane. The environment-friendly surfactant made entirely from silkworm pupae could promote sustainable development of the silk industry. PMID:24651079

The effects of n-3 fatty acid deficiency and repletion upon the fatty acid composition and function of the brain and retina.

PubMed

Connor, W E; Neuringer, M

1988-01-01

It is now apparent that both n-6 and n-3 fatty acids are essential for normal development in mammals, and that each has specific functions in the body. N-6 fatty acids are necessary primarily for growth, reproduction, and the maintenance of skin integrity, whereas n-3 fatty acids are involved in the development and function of the retina and cerebral cortex and perhaps other organs such as the testes. Fetal life and infancy are particularly critical for the nervous tissue development. Therefore, with respect to human nutrition, adequate amounts of omega-3 fatty acids should be provided during pregnancy, lactation and infancy, but probably throughout life. We estimate that adequate levels are provided by diets containing 6-8% kcals from linoleic acid and 1% from n-3 fatty acids (alpha-linolenic acid, EPA and DHA), resulting in a ratio of n-6 to n-3 fatty acids of 4:1 to 10:1. The essentiality of n-3 fatty acids resides in their presence as DHA in vital membranes of the photoreceptors of the retina and the synaptosomes and other subcellular membranes of the brain. The replacement of DHA in deficient animals by the n-6 fatty acid, 22:5, results in abnormal functioning of the membranes for reasons as yet to be ascertained. Most significant is the lability of fatty acid composition in the retinal and brain of deficient animals. Dietary fish oil, which contains EPA and DHA, will readily lead to a change in the composition of the membrane of retina and brain, fatty acids, with DHA replacing the n-6 fatty acid, 22:5. The interrelationships between the chemistry of neural and retinal membranes as affected by diet and their biological functioning provides an exciting prospect for future investigations.

Dietary flavonoids increase plasma very long-chain (n-3) fatty acids in rats.

PubMed

Toufektsian, Marie-Claire; Salen, Patricia; Laporte, François; Tonelli, Chiara; de Lorgeril, Michel

2011-01-01

Flavonoids probably contribute to the health benefits associated with the consumption of fruit and vegetables. However, the mechanisms by which they exert their effects are not fully elucidated. PUFA of the (n-3) series also have health benefits. Epidemiological and clinical studies have suggested that wine flavonoids may interact with the metabolism of (n-3) PUFA and increase their blood and cell levels. The present studies in rats were designed to assess whether flavonoids actually increase plasma levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the main very long-chain (n-3) PUFA. Rats were fed a corn-derived anthocyanin (ACN)-rich (ACN-rich) or ACN-free diet with constant intakes of plant and marine (n-3) PUFA for 8 wk (Expt. 1). Plasma fatty acids were measured by GC. The ACN-rich diet contained ~0.24 ± 0.01 mg of ACN/g pellets. There were no significant differences between groups in the main saturated, monounsaturated, and (n-6) fatty acids. In contrast, plasma EPA and DHA were greater in the ACN-rich diet group than in the ACN-free diet group (P < 0.05). We obtained similar results in 2 subsequent experiments in which rats were administered palm oil (80 μL/d) and consumed the ACN-rich or ACN-free diet (Expt. 2) or were supplemented with fish oil (60 mg/d, providing 35 mg DHA and 12 mg EPA) and consumed the ACN-rich or ACN-free diet (Expt. 3). In both experiments, plasma EPA and DHA were significantly greater in the ACN-rich diet group. These studies demonstrate that the consumption of flavonoids increases plasma very long-chain (n-3) PUFA levels. These data confirm previous clinical and epidemiological studies and provide new insights into the health benefits of flavonoids.

Polypeptide having an amino acid replaced with N-benzylglycine

DOEpatents

Mitchell, Alexander R.; Young, Janis D.

1996-01-01

The present invention relates to one or more polypeptides having useful biological activity in a mammal, which comprise: a polypeptide related to bradykinin of four to ten amino acid residues wherein one or more specific amino acids in the polypeptide chain are replaced with achiral N-benzylglycine. These polypeptide analogues have useful potent agonist or antagonist pharmacological properties depending upon the structure. A preferred polypeptide is (N-benzylglycine.sup.7)-bradykinin.

Long-chain n-3 and n-6 polyunsaturated fatty acids and risk of atrial fibrillation: Results from a Danish cohort study.

PubMed

Mortensen, Lotte Maxild; Lundbye-Christensen, Søren; Schmidt, Erik Berg; Calder, Philip C; Schierup, Mikkel Heide; Tjønneland, Anne; Parner, Erik T; Overvad, Kim

2017-01-01

Studies of the relation between polyunsaturated fatty acids and risk of atrial fibrillation have been inconclusive. The risk of atrial fibrillation may depend on the interaction between n-3 and n-6 polyunsaturated fatty acids as both types of fatty acids are involved in the regulation of systemic inflammation. We investigated the association between dietary intake of long chain polyunsaturated fatty acids (individually and in combination) and the risk of atrial fibrillation with focus on potential interaction between the two types of polyunsaturated fatty acids. The risk of atrial fibrillation in the Diet, Cancer and Health Cohort was analyzed using the pseudo-observation method to explore cumulative risks on an additive scale providing risk differences. Dietary intake of long chain polyunsaturated fatty acids was assessed by food frequency questionnaires. The main analyses were adjusted for the dietary intake of n-3 α-linolenic acid and n-6 linoleic acid to account for endogenous synthesis of long chain polyunsaturated fatty acids. Interaction was assessed as deviation from additivity of absolute association measures (risk differences). Cumulative risks in 15-year age periods were estimated in three strata of the cohort (N = 54,737). No associations between intake of n-3 or n-6 long chain polyunsaturated fatty acids and atrial fibrillation were found, neither when analyzed separately as primary exposures nor when interaction between n-3 and n-6 long chain polyunsaturated fatty acids was explored. This study suggests no association between intake of long chain polyunsaturated fatty acids and risk of atrial fibrillation.

Plant Wax n-Alkane and n-Alkanoic Acid Signatures Overprinted by Microbial Contributions and Old Carbon in Meromictic Lake Sediments

NASA Astrophysics Data System (ADS)

Makou, Matthew; Eglinton, Timothy; McIntyre, Cameron; Montluçon, Daniel; Antheaume, Ingrid; Grossi, Vincent

2018-01-01

Specific n-alkanes and n-alkanoic acids are commonly used as biomarkers in paleoenvironmental reconstruction, yet any individual homologue may originate from multiple biological sources. Here we improve source and age controls for these compounds in meromictic systems by measuring the radiocarbon (14C) ages of specific homologues preserved in twentieth century Lake Pavin (France) sediments. In contrast to many studies, 14C ages generally decreased with increasing carbon chain length, from 7.3 to 2.6 ka for the C14-C30 n-alkanoic acids and from 9.2 to 0.3 ka for the C21-C33 n-alkanes. Given a known hard water effect, these values suggest that aquatic microbial sources predominate and contributed to most of the homologues measured. Only the longest chain n-alkanes exclusively represent inputs of higher plant waxes, which were previously sequestered in soils over centennial to millennial timescales prior to transport and deposition. These findings suggest that biomarker source and age should be carefully established for lacustrine settings.

Degradation of bromamine acid by nanoscale zero-valent iron (nZVI) supported on sepiolite.

PubMed

Fei, Xuening; Cao, Lingyun; Zhou, Lifeng; Gu, Yingchun; Wang, Xiaoyang

2012-01-01

Sepiolite, a natural nano-material, was chosen as a carrier to prepare supported nanoscale zero-valent iron (nZVI). The effects of preparation conditions, including mass ratio of nZVI and activated sepiolite and preparation pH value, on properties of the supported nZVI were investigated. The results showed that the optimal mass ratio of nZVI and sepiolite was 1.12:1 and the optimal pH value was 7. The supported nZVI was characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and energy dispersive spectrometer (EDS), and furthermore an analogy model of the supported nZVI was set up. Compared with the nZVI itself, the supported nZVI was more stable in air and possessed better water dispersibility, which were beneficial for the degradation of bromamine acid aqueous solution. The degradation characteristics, such as effects of supported nZVI dosage, initial concentration and initial pH value of the solution on the decolorization efficiency were also investigated. The results showed that in an acidic environment the supported nZVI with a dosage of 2 g/L showed high activity in the degradation of bromamine acid with an initial concentration of 1,000 mg/L, and the degree of decolorization could reach up to 98%.

In Vivo Epithelial Wound Repair Requires Mobilization of Endogenous Intracellular and Extracellular Calcium*

PubMed Central

Aihara, Eitaro; Hentz, Courtney L.; Korman, Abraham M.; Perry, Nicholas P. J.; Prasad, Vikram; Shull, Gary E.; Montrose, Marshall H.

2013-01-01

We report that a localized intracellular and extracellular Ca2+ mobilization occurs at the site of microscopic epithelial damage in vivo and is required to mediate tissue repair. Intravital confocal/two-photon microscopy continuously imaged the surgically exposed stomach mucosa of anesthetized mice while photodamage of gastric epithelial surface cells created a microscopic lesion that healed within 15 min. Transgenic mice with an intracellular Ca2+-sensitive protein (yellow cameleon 3.0) report that intracellular Ca2+ selectively increases in restituting gastric epithelial cells adjacent to the damaged cells. Pretreatment with U-73122, indomethacin, 2-aminoethoxydiphenylborane, or verapamil inhibits repair of the damage and also inhibits the intracellular Ca2+ increase. Confocal imaging of Fura-Red dye in luminal superfusate shows a localized extracellular Ca2+ increase at the gastric surface adjacent to the damage that temporally follows intracellular Ca2+ mobilization. Indomethacin and verapamil also inhibit the luminal Ca2+ increase. Intracellular Ca2+ chelation (1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid/acetoxymethyl ester, BAPTA/AM) fully inhibits intracellular and luminal Ca2+ increases, whereas luminal calcium chelation (N-(2-hydroxyetheyl)-ethylendiamin-N,N,N′-triacetic acid trisodium, HEDTA) blocks the increase of luminal Ca2+ and unevenly inhibits late-phase intracellular Ca2+ mobilization. Both modes of Ca2+ chelation slow gastric repair. In plasma membrane Ca-ATPase 1+/− mice, but not plasma membrane Ca-ATPase 4−/− mice, there is slowed epithelial repair and a diminished gastric surface Ca2+ increase. We conclude that endogenous Ca2+, mobilized by signaling pathways and transmembrane Ca2+ transport, causes increased Ca2+ levels at the epithelial damage site that are essential to gastric epithelial cell restitution in vivo. PMID:24121509

The Toxicity of Perfluoro-N-Decanoic Acid and 2,3,7,8- Tetrachlorodibenzo-P-Dioxin in L5178Y Mouse Lymphoma Cells

DTIC Science & Technology

1983-03-01

ABSTRACT (Continue on reverse side If necessary and identify by block number) Perfluoro -n-decanoic acid ( PFDA ) causes toxic sequelae in vivo very similar to...acid analogs. All polyfluorinated acids tested (either perfluorinated or w-hydro-analogs) with chain length 9 or greater caused impairment of clone...of 5 to 7. The acute and subchronic toxicity of ammonium perfluoro -n-octanoate ( PFOA ) has been described in detail in both rats and rhesus monkeys

Chemopreventive effects of rofecoxib and folic acid on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats.

PubMed

Fei, Su Juan; Xiao, Shu Dong; Peng, Yan Shen; Chen, Xiao Yu; Shi, Yao

2006-01-01

Epidemiological and experimental studies indicate that non-steroidal anti-inflammatory drugs (NSAIDs) are chemopreventive agents of gastrointestinal cancers, but few studies on gastric cancer have been carried out. A decrease in folic acid supplement and subsequent DNA hypomethylation are related to gastrointestinal cancers, and it has been shown that high-dose folic acid may interfere with gastric carcinogenesis in dogs. The objective of this study was to investigate the effects of rofecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, and folic acid on the chemoprevention of gastric cancer induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Wistar rats, and to evaluate the cell proliferation of gastric mucosa in different experimental groups. Eighty male Wistar rats were randomly divided into five groups (16 rats in each group). In the control group, the rats were given pure water and basal diet. In the MNNG group, the rats received MNNG in drinking water (100 mg/L) and basal diet. In the MNNG + low-dose rofecoxib group, the rats were given MNNG and rofecoxib 5 mg/kg per day with basal diet. In the MNNG + high-dose rofecoxib group, the rats were given MNNG and rofecoxib 15 mg/kg per day with basal diet. In the MNNG + folic acid group, the rats were given MNNG and folic acid 5 mg/kg per day with basal diet. The experiment was terminated at 50 weeks, and all rats were killed. Blood samples of 3 mL were obtained for measurement of serum folic acid concentrations in the control group, the MNNG group and the MNNG + folic acid group by using chemiluminescent method. The stomach was removed from all rats for histopathological examination and immunohistochemical study. Proliferating cell nuclear antigen (PCNA) expression in gastric epithelial cells was also determined. In the MNNG group, five of 11 rats (45.5%) developed gastric cancer, while in all other four groups no gastric cancer was found (P < 0.05). The positivity rate of PCNA expression in the cancerous

Production of Structured Triacylglycerols Containing Palmitic Acids at sn-2 Position and Docosahexaenoic Acids at sn-1, 3 Positions.

PubMed

Liu, Yanjun; Guo, Yongli; Sun, Zhaomin; Jie, Xu; Li, Zhaojie; Wang, Jingfeng; Wang, Yuming; Xue, Changhu

2015-01-01

Docosahexaenoic acid supplementation has been shown well-established health benefits that justify their use as functional ingredients in healthy foods and nutraceutical products. Structured triacylglycerols rich in 1,3-docosahexenoyl-2-palmitoyl-sn-glycerol were produced from algal oil (Schizochytrium sp) which was prepared by a two-step process. Novozym 435 lipase was used to produce tripalmitin. Tripalmitin was then used to produce the final structured triacylglycerol (STAG) through interesterification reactions using Lipozyme RM IM. The optimum conditions for the enzymatic reaction were a mole ratio of tripalmitin/fatty acid ethyl esters 1:9, 60°C, 10% enzyme load (wt % of substrates), 10 h; the enzymatic product contained 51.6% palmitic acid (PA), 30.13% docosahexaenoic acid (DHA, C22:6 n-3) and 5.33% docosapentanoic acid (DPA, C22:5 n-3), 12.15% oleic acid (OLA). This STAG can be used as a functional ingredient in dietary supplementation to provide the benefits of DHA.

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines.

PubMed

Bennett, John M; Shapiro, Jonathan D; Choinski, Krystina N; Mei, Yingbin; Aulita, Sky M; Dominguez, Giovanny M; Majireck, Max M

2018-01-03

Decomposition of N-tosyl-1,2,3-triazoles with rhodium(II) acetate dimer in the presence of alcohols forms synthetically versatile N-(2-alkoxyvinyl)sulfonamides, which react under a variety of conditions to afford useful N- and O-containing compounds. Acid-catalyzed addition of alcohols or thiols to N-(2-alkoxyvinyl)sulfonamide-containing phthalans provides access to ketals and thioketals, respectively. Selective reduction of the vinyl group in N-(2-alkoxyvinyl)sulfonamide-containing phthalans via hydrogenation yields the corresponding phthalan in good yield, whereas reduction with sodium bis(2-methoxyethoxy)aluminumhydride generates a ring-opened phenethylamine analogue. Because the N-(2-alkoxyvinyl)sulfonamide functional group is synthetically versatile, but often hydrolytically unstable, this protocol emphasizes key techniques in preparing, handling, and reacting these pivotal substrates in several useful transformations.

N-Acyl derivatives of Asn, new bacterial N-acyl D-amino acids with surfactant activity.

PubMed

Peypoux, F; Laprévote, O; Pagadoy, M; Wallach, J

2004-03-01

New N-acyl D-amino acids were isolated from Bacillus pumilus IM 1801. Their structures were determined by chemical analysis and mass spectrometry. The lipid part was identified as a mixture of fatty acids with 11, 12, 13, 15, and 16 carbon atoms in the iso, anteiso or n configuration linked by an amide bond with a D-asparagine. They exhibited surfactant properties.

Structural diversity in Ni II cluster chemistry: Ni 5, Ni 6, and {NiNa 2} n complexes bearing the Schiff-base ligand N-naphthalidene-2-amino-5-chlorobenzoic acid

DOE PAGES

Perlepe, Panagiota S.; Cunha-Silva, Luis; Bekiari, Vlasoula; ...

2016-05-23

The employment of the fluorescent bridging and chelating ligand N-naphthalidene-2-amino-5-chlorobenzoic acid (nacbH 2) in Ni II cluster chemistry has led to a series of pentanuclear and hexanuclear compounds with different structural motifs, magnetic and optical properties, as well as an interesting 1-D coordination polymer. Synthetic parameters such as the inorganic anion present in the NiX 2 starting materials (X = ClO 4 - or Cl -), the reaction solvent and the nature of the organic base employed for the deprotonation of nacbH 2 were also proved to be structure-directing components. Undoubtedly, the reported results demonstrate the rich coordination chemistry ofmore » nacbH 2 in the presence of Ni II metal ions and the ability of this chelate to adopt a variety of different modes, thus fostering the formation of high-nuclearity molecules with many physical properties.« less

Chiral discrimination of α-hydroxy acids and N-Ts-α-amino acids induced by tetraaza macrocyclic chiral solvating agents by using 1H NMR spectroscopy.

PubMed

Lv, Caixia; Feng, Lei; Zhao, Hongmei; Wang, Guo; Stavropoulos, Pericles; Ai, Lin

2017-02-21

In the field of chiral recognition, reported chiral discrimination by 1 H NMR spectroscopy has mainly focused on various chiral analytes with a single chiral center, regarded as standard chiral substrates to evaluate the chiral discriminating abilities of a chiral auxiliary. Among them, chiral α-hydroxy acids, α-amino acids and their derivatives are chiral organic molecules involved in a wide variety of biological processes, and also play an important role in the area of preparation of pharmaceuticals, as they are part of the synthetic process in the production of chiral drug intermediates and protein-based drugs. In this paper, several α-hydroxy acids and N-Ts-α-amino acids were used to evaluate the chiral discriminating abilities of tetraaza macrocyclic chiral solvating agents (TAMCSAs) 1a-1d by 1 H NMR spectroscopy. The results indicate that α-hydroxy acids and N-Ts-α-amino acids were successfully discriminated in the presence of TAMCSAs 1a-1d by 1 H NMR spectroscopy in most cases. The enantiomers of the α-hydroxy acids and N-Ts-α-amino acids were assigned based on the change of integration of the 1 H NMR signals of the corresponding protons. The enantiomeric excesses (ee) of N-Ts-α-amino acids 11 with different optical compositions were calculated based on the integration of the 1 H NMR signals of the CH 3 protons (Ts group) of the enantiomers of (R)- and (S)-11 in the presence of TAMCSA 1b. At the same time, the possible chiral discriminating behaviors have been discussed by means of the Job plots of (±)-2 with TAMCSAs 1b and proposed theoretical models of the enantiomers of 2 and 6 with TAMCSA 1a, respectively.

n-hydrocarbons conversions over metal-modified solid acid catalysts

NASA Astrophysics Data System (ADS)

Zarubica, A.; Ranđelović, M.; Momčilović, M.; Radulović, N.; Putanov, P.

2013-12-01

The quality of a straight-run fuel oil can be improved if saturated n-hydrocarbons of low octane number are converted to their branched counterparts. Poor reactivity of traditional catalysts in isomerization reactions imposed the need for the development of new catalysts among which noble metal promoted acid catalysts, liquid and/or solid acid catalysts take a prominent place. Sulfated zirconia and metal promoted sulfated zirconia exhibit high activity for the isomerization of light alkanes at low temperatures. The present paper highlights the original results which indicate that the modification of sulfated zirconia by incorporation of metals (platinum and rhenium) significantly affects catalytic performances in n-hydrocarbon conversion reactions. Favourable activity/selectivity of the promoted sulfated zirconia depends on the crystal phase composition, critical crystallites sizes, platinum dispersion, total acidity and type of acidity. Attention is also paid to the recently developed solid acid catalysts used in other conversion reactions of hydrocarbons.

Amino acid substitutions in the neuraminidase protein of an H9N2 avian influenza virus affect its airborne transmission in chickens.

PubMed

Lv, Jing; Wei, Liangmeng; Yang, Yan; Wang, Bingxiao; Liang, Wei; Gao, Yuwei; Xia, Xianzhu; Gao, Lili; Cai, Yumei; Hou, Peiqiang; Yang, Huili; Wang, Airong; Huang, Rong; Gao, Jing; Chai, Tongjie

2015-04-18

Cases of H9N2 avian influenza virus (AIV) in poultry are increasing throughout many Eurasian countries, and co-infections with other pathogens have resulted in high morbidity and mortality in poultry. Few studies have investigated the genetic factors of virus airborne transmission which determine the scope of this epidemic. In this study, we used specific-pathogen-free chickens housed in isolators to investigate the airborne transmissibility of five recombinant H9N2 AIV rescued by reverse genetic technology. The results show that airborne transmission of A/Chicken/Shandong/01/2008 (SD01) virus was related to the neuraminidase (NA) gene, and four amino acid mutations (D368E, S370L, E313K and G381D) within the head region of the SD01 NA, reduced virus replication in the respiratory tract of chickens, reduced virus NA activity, and resulted in a loss of airborne transmission ability in chickens. Similarly, reverse mutations of these four amino acids in the NA protein of r01/NASS virus, conferred an airborne transmission ability to the recombinant virus. We conclude that these four NA residues may be significant genetic markers for evaluating potential disease outbreak of H9N2 AIV, and propose that immediate attention should be paid to the airborne transmission of this virus.

Amino Acid Substitutions in Polymerase Basic Protein 2 Gene Contribute to the Pathogenicity of the Novel A/H7N9 Influenza Virus in Mammalian Hosts

PubMed Central

Mok, Chris Ka Pun; Lee, Horace Hok Yeung; Lestra, Maxime; Nicholls, John Malcolm; Chan, Michael Chi Wai; Sia, Sin Fun; Zhu, Huachen; Poon, Leo Lit Man; Guan, Yi

2014-01-01

ABSTRACT A novel avian-origin influenza A/H7N9 virus emerged in 2013 to cause more than 130 cases of zoonotic human disease, with an overall case fatality rate of around 30% in cases detected. It has been shown that an E-to-K amino acid change at residue 627 of polymerase basic protein 2 (PB2) occurred frequently in the H7N9 isolates obtained from humans but not in viruses isolated from poultry. Although this mutation has been reported to confer increased mammalian pathogenicity in other avian influenza subtypes, it has not been experimentally investigated in the H7N9 virus. In this study, we determined the contribution of PB2-E627K in H7N9 virus to its pathogenicity in mammalian hosts. In addition, the compensatory role of the PB2 mutations T271A, Q591K, and D701N in H7N9 virus was investigated. We characterized the activity of polymerase complexes with these PB2 mutations and found that they enhance the polymerase activity in human 293T cells. The rescued mutants enhanced growth in mammalian cells in vitro. Mice infected with the H7N9 mutant containing the avian signature protein PB2-627E showed a marked decrease in disease severity (weight loss) and pathology compared to mice infected with the wild-type strain (PB2-627K) or other PB2 mutants. Also, mutants with PB2-627E showed lower virus replication and proinflammatory cytokine responses in the lungs of the virus-infected mice, which may contribute to pathogenicity. Our results suggest that these amino acid substitutions contribute to mouse pathogenicity and mammalian adaptation. IMPORTANCE A novel avian H7N9 influenza A virus emerged in east China in 2013 to cause zoonotic human disease associated with significant mortality. It is important to understand the viral genetic markers of mammalian adaptation and disease severity in this H7N9 virus. Since many human (but not avian) H7N9 virus isolates have an amino acid substitution at position E627K in the polymerase basic protein 2 (PB2) gene, we investigated the