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Sample records for aldehyde oxidation level

  1. Efficient and Highly Aldehyde Selective Wacker Oxidation

    KAUST Repository

    Teo, Peili

    2012-07-06

    A method for efficient and aldehyde-selective Wacker oxidation of aryl-substituted olefins using PdCl 2(MeCN) 2, 1,4-benzoquinone, and t-BuOH in air is described. Up to a 96% yield of aldehyde can be obtained, and up to 99% selectivity can be achieved with styrene-related substrates. © 2012 American Chemical Society.

  2. Reducing the Oxidation Level of Dextran Aldehyde in a Chitosan/Dextran-Based Surgical Hydrogel Increases Biocompatibility and Decreases Antimicrobial Efficacy.

    Science.gov (United States)

    Chan, Maggie; Brooks, Heather J L; Moratti, Stephen C; Hanton, Lyall R; Cabral, Jaydee D

    2015-06-16

    A highly oxidized form of a chitosan/dextran-based hydrogel (CD-100) containing 80% oxidized dextran aldehyde (DA-100) was developed as a post-operative aid, and found to significantly prevent adhesion formation in endoscopic sinus surgery (ESS). However, the CD-100 hydrogel showed moderate in vitro cytotoxicity to mammalian cell lines, with the DA-100 found to be the cytotoxic component. In order to extend the use of the hydrogel to abdominal surgeries, reformulation using a lower oxidized DA (DA-25) was pursued. The aim of the present study was to compare the antimicrobial efficacy, in vitro biocompatibility and wound healing capacity of the highly oxidized CD-100 hydrogel with the CD-25 hydrogel. Antimicrobial studies were performed against a range of clinically relevant abdominal microorganisms using the micro-broth dilution method. Biocompatibility testing using human dermal fibroblasts was assessed via a tetrazolium reduction assay (MTT) and a wound healing model. In contrast to the original DA-100 formulation, DA-25 was found to be non-cytotoxic, and showed no overall impairment of cell migration, with wound closure occurring at 72 h. However, the lower oxidation level negatively affected the antimicrobial efficacy of the hydrogel (CD-25). Although the CD-25 hydrogel's antimicrobial efficacy and anti-fibroblast activity is decreased when compared to the original CD-100 hydrogel formulation, previous in vivo studies show that the CD-25 hydrogel remains an effective, biocompatible barrier agent in the prevention of postoperative adhesions.

  3. Reducing the Oxidation Level of Dextran Aldehyde in a Chitosan/Dextran-Based Surgical Hydrogel Increases Biocompatibility and Decreases Antimicrobial Efficacy

    Directory of Open Access Journals (Sweden)

    Maggie Chan

    2015-06-01

    Full Text Available A highly oxidized form of a chitosan/dextran-based hydrogel (CD-100 containing 80% oxidized dextran aldehyde (DA-100 was developed as a post-operative aid, and found to significantly prevent adhesion formation in endoscopic sinus surgery (ESS. However, the CD-100 hydrogel showed moderate in vitro cytotoxicity to mammalian cell lines, with the DA-100 found to be the cytotoxic component. In order to extend the use of the hydrogel to abdominal surgeries, reformulation using a lower oxidized DA (DA-25 was pursued. The aim of the present study was to compare the antimicrobial efficacy, in vitro biocompatibility and wound healing capacity of the highly oxidized CD-100 hydrogel with the CD-25 hydrogel. Antimicrobial studies were performed against a range of clinically relevant abdominal microorganisms using the micro-broth dilution method. Biocompatibility testing using human dermal fibroblasts was assessed via a tetrazolium reduction assay (MTT and a wound healing model. In contrast to the original DA-100 formulation, DA-25 was found to be non-cytotoxic, and showed no overall impairment of cell migration, with wound closure occurring at 72 h. However, the lower oxidation level negatively affected the antimicrobial efficacy of the hydrogel (CD-25. Although the CD-25 hydrogel’s antimicrobial efficacy and anti-fibroblast activity is decreased when compared to the original CD-100 hydrogel formulation, previous in vivo studies show that the CD-25 hydrogel remains an effective, biocompatible barrier agent in the prevention of postoperative adhesions.

  4. The oxidation of the aldehyde groups in dialdehyde starch

    NARCIS (Netherlands)

    Haaksman, I.K.; Besemer, A.C.; Jetten, J.M.; Timmermans, J.W.; Slaghek, T.M.

    2006-01-01

    This paper describes the difference in relative reactivity of the aldehyde groups present in dialdehyde starch towards different oxidising agents. The oxidation of dialdehyde starch with peracetic acid and sodium bromide leads to only partial oxidation to give mono-aldehyde-carboxy starch, while oxi

  5. Release and Formation of Oxidation-Related Aldehydes during Wine Oxidation.

    Science.gov (United States)

    Bueno, Mónica; Carrascón, Vanesa; Ferreira, Vicente

    2016-01-27

    Twenty-four Spanish wines were subjected to five consecutive cycles of air saturation at 25 °C. Free and bound forms of carbonyls were measured in the initial samples and after each saturation. Nonoxidized commercial wines contain important and sensory relevant amounts of oxidation-related carbonyls under the form of odorless bound forms. Models relating the contents in total aldehydes to the wine chemical composition suggest that fermentation can be a major origin for Strecker aldehydes: methional, phenylacetaldehyde, isobutyraldehyde, 2-methylbutanal, and isovaleraldehyde. Bound forms are further cleaved, releasing free aldehydes during the first steps of wine oxidation, as a consequence of equilibrium shifts caused by the depletion of SO2. At low levels of free SO2, de novo formation and aldehyde degradation are both observed. The relative importance of these phenomena depends on both the aldehyde and the wine. Models relating aldehyde formation rates to wine chemical composition suggest that amino acids are in most cases the most important precursors for de novo formation.

  6. Research advances in the catalysts for the selective oxidation of ethane to aldehydes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhe; ZHAO Zhen; XU Chunming

    2005-01-01

    Selective oxidation of ethane to aldehydes is one of the most difficult processes in the catalysis researches of low alkanes. The development of selective oxidation of ethane to aldehydes (formaldehyde, acetaldehyde and acrolein) is discussed. The latest progress of the catalysts, including bulk or supported metal oxide catalysts, highly dispersed and isolated active sites catalysts, and the photo-catalytic ethane oxidation catalysts, partial oxidation of ethane in the gas phase, and the proposed reaction pathways from ethane to aldehydes are involved.

  7. Nitric oxide mediates the stress response induced by diatom aldehydes in the sea urchin Paracentrotus lividus.

    Directory of Open Access Journals (Sweden)

    Giovanna Romano

    Full Text Available Diatoms are ubiquitous and abundant primary producers that have been traditionally considered as a beneficial food source for grazers and for the transfer of carbon through marine food webs. However, many diatom species produce polyunsaturated aldehydes that disrupt development in the offspring of grazers that feed on these unicellular algae. Here we provide evidence that production of the physiological messenger nitric oxide increases after treatment with the polyunsaturated aldehyde decadienal in embryos of the sea urchin Paracentrotus lividus. At high decadienal concentrations, nitric oxide mediates initial apoptotic events leading to loss of mitochondrial functionality through the generation of peroxynitrite. At low decadienal concentrations, nitric oxide contributes to the activation of hsp70 gene expression thereby protecting embryos against the toxic effects of this aldehyde. When nitric oxide levels were lowered by inhibiting nitric oxide synthase activity, the expression of hsp70 in swimming blastula decreased and the proportion of abnormal plutei increased. However, in later pluteus stages nitric oxide was no longer able to exert this protective function: hsp70 and nitric oxide synthase expression decreased with a consequent increase in the expression of caspase-8. Our findings that nitric oxide production increases rapidly in response to a toxic exogenous stimulus opens new perspectives on the possible role of this gas as an important messenger to environmental stress in sea urchins and for understanding the cellular mechanisms underlying toxicity during diatom blooms.

  8. Nitric oxide mediates the stress response induced by diatom aldehydes in the sea urchin Paracentrotus lividus.

    Science.gov (United States)

    Romano, Giovanna; Costantini, Maria; Buttino, Isabella; Ianora, Adrianna; Palumbo, Anna

    2011-01-01

    Diatoms are ubiquitous and abundant primary producers that have been traditionally considered as a beneficial food source for grazers and for the transfer of carbon through marine food webs. However, many diatom species produce polyunsaturated aldehydes that disrupt development in the offspring of grazers that feed on these unicellular algae. Here we provide evidence that production of the physiological messenger nitric oxide increases after treatment with the polyunsaturated aldehyde decadienal in embryos of the sea urchin Paracentrotus lividus. At high decadienal concentrations, nitric oxide mediates initial apoptotic events leading to loss of mitochondrial functionality through the generation of peroxynitrite. At low decadienal concentrations, nitric oxide contributes to the activation of hsp70 gene expression thereby protecting embryos against the toxic effects of this aldehyde. When nitric oxide levels were lowered by inhibiting nitric oxide synthase activity, the expression of hsp70 in swimming blastula decreased and the proportion of abnormal plutei increased. However, in later pluteus stages nitric oxide was no longer able to exert this protective function: hsp70 and nitric oxide synthase expression decreased with a consequent increase in the expression of caspase-8. Our findings that nitric oxide production increases rapidly in response to a toxic exogenous stimulus opens new perspectives on the possible role of this gas as an important messenger to environmental stress in sea urchins and for understanding the cellular mechanisms underlying toxicity during diatom blooms. PMID:22022485

  9. Mitochondrial aldehyde dehydrogenase 2 protects gastric mucosa cells against DNA damage caused by oxidative stress.

    Science.gov (United States)

    Duan, Yantao; Gao, Yaohui; Zhang, Jun; Chen, Yinan; Jiang, Yannan; Ji, Jun; Zhang, Jianian; Chen, Xuehua; Yang, Qiumeng; Su, Liping; Zhang, Jun; Liu, Bingya; Zhu, Zhenggang; Wang, Lishun; Yu, Yingyan

    2016-04-01

    Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is a member of the aldehyde dehydrogenase superfamily and is involved with the metabolic processing of aldehydes. ALDH2 plays a cytoprotective role by removing aldehydes produced during normal metabolism. We examined the cytoprotective role of ALDH2 specifically in gastric mucosa cells. Overexpression of ALDH2 increased the viability of gastric mucosa cells treated with H2O2, while knockdown of ALDH2 had an opposite effect. Moreover, overexpression of ALDH2 protected gastric mucosa cells against oxidative stress-induced apoptosis as determined by flow cytometry, Hoechst 33342, and TUNEL assays. Consistently, ALDH2 knockdown had an opposite effect. Additionally, DNA damage was ameliorated in ALDH2-overexpressing gastric mucosa cells treated with H2O2. We further identified that this cytoprotective role of ALDH2 was mediated by metabolism of 4-hydroxynonenal (4-HNE). Consistently, 4-HNE mimicked the oxidative stress induced by H2O2 in gastric mucosa cells. Treatment with 4-HNE increased levels of DNA damage in ALDH2-knockdown GES-1 cells, while overexpression of ALDH2 decreased 4-HNE-induced DNA damage. These findings suggest that ALDH2 can protect gastric mucosa cells against DNA damage caused by oxidative stress by reducing levels of 4-HNE.

  10. Catalytic Fehling's Reaction: An Efficient Aerobic Oxidation of Aldehyde Catalyzed by Copper in Water.

    Science.gov (United States)

    Liu, Mingxin; Li, Chao-Jun

    2016-08-26

    The first example of homogeneous copper-catalyzed aerobic oxidation of aldehydes is reported. This method utilizes atmospheric oxygen as the sole oxidant, proceeds under extremely mild aqueous conditions, and covers a wide range of various functionalized aldehydes. Chromatography is generally not necessary for product purification. PMID:27505714

  11. Oxidative desulfurization of diesel with TBHP/isobutyl aldehyde/air oxidation system

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Wei; Wang, Chengyong; Lin, Peng; Lu, Xiaoping [Institute of Sonochemical Engineering, Nanjing University of Technology, Nanjing 210009, Jiangsu (China)

    2011-01-15

    Oxidative desulfurization of hydrogenation diesel (40 mL) was studied using air as oxidant, tert-butyl hydroperoxide (TBHP) as radical initiator at ambient pressure and moderate temperature in the presence of isobutyl aldehyde. TBHP could accelerate the production of carbonyl radical and its peroxidation. When the molar fraction of TBHP was 5 mmol, the conversion of DBT could reach 96.1% in the present of 20 mmol isobutyl aldehyde and air, which was more than that of 85.5% without initiator. The air was an effective oxidant and acetonitrile was an optimal solvent in this process. The sulfur content of the hydrogenation diesel could be reduced from 403 to 13 ppm (96.8% removed) under the synergistic effect of air, TBHP and isobutyl aldehyde. (author)

  12. The carbonyl oxide-aldehyde complex: a new intermediate of the ozonolysis reaction

    Science.gov (United States)

    Cremer, Dieter; Kraka, Elfi; McKee, M. L.; Radharkrishnan, T. P.

    1991-12-01

    MP4(SDQ)/6-31G (d,p) calculations suggest that the ozonolysis of alkenes in solution phase does not proceed via carbonyl oxide, but via a dipole complex between aldehyde and carbonyl oxide, which is 9 kcal/mol more stable than the separated molecules. The dipole complex is probably formed in the solvent cage upon decomposition of primary ozonide to aldehyde and carbonyl oxide. Rotation of either aldehyde or carbonyl oxide in the solvent cage leads to an antiparallel alignment of molecular dipole moments and dipole-dipole attraction.

  13. Modelling of the partial oxidation of {alpha}, {beta}-unsaturated aldehydes on Mo-V-oxides based catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Boehnke, H.; Petzoldt, J.C.; Stein, B.; Weimer, C.; Gaube, J.W. [Technische Univ. Darmstadt (Germany). Inst. fuer Chemische Technologie

    1998-12-31

    A kinetic model based on the Mars-van Krevelen mechanism that allows to describe the microkinetics of the heterogeneously catalysed partial oxidation of {alpha}, {beta}-unsaturated aldehydes is presented. This conversion is represented by a network, composed of the oxidation of the {alpha}, {beta}-unsaturated aldehyde towards the {alpha}, {beta}-unsaturated carboxylic acid and the consecutive oxidation of the acid as well as the parallel reaction of the aldehyde to products of deeper oxidation. The reaction steps of aldehyde respectively acid oxidation and catalyst reoxidation have been investigated separately in transient experiments. The combination of steady state and transient experiments has led to an improved understanding of the interaction of the catalyst with the aldehyde and the carboxylic acids as well as to a support of the kinetic model assumptions. (orig.)

  14. Oxidation of Group 8 transition-Metal Hydrides and Ionic Hydrogenation of Ketones and Aldehydes

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kjell-Tore

    1996-08-01

    Transition-metal hydrides have received considerable attention during the last decades because of their unusual reactivity and their potential as homogeneous catalysts for hydrogenation and other reactions of organic substrates. An important class of catalytic processes where transition-metal hydrides are involved is the homogeneous hydrogenation of alkenes, alkynes, ketones, aldehydes, arenes and nitro compounds. This thesis studies the oxidation of Group 8 transition-metal hydrides and the ionic hydrogenation of ketones and aldehydes.

  15. Aerobic oxidation of aldehydes under ambient conditions using supported gold nanoparticle catalysts

    DEFF Research Database (Denmark)

    Marsden, Charlotte Clare; Taarning, Esben; Hansen, David;

    2008-01-01

    A new, green protocol for producing simple esters by selectively oxidizing an aldehyde dissolved in a primary alcohol has been established, utilising air as the oxidant and supported gold nanoparticles as catalyst. The oxidative esterifications proceed with excellent selectivities at ambient cond...... conditions; the reactions can be performed in an open flask and at room temperature. Benzaldehyde is even oxidised at a reasonable rate below -70 degrees C. Acrolein is oxidised to methyl acrylate in high yield using the same protocol....

  16. Aldehyde-Selective Wacker-Type Oxidation of Unbiased Alkenes Enabled by a Nitrite Co-Catalyst

    KAUST Repository

    Wickens, Zachary K.

    2013-09-13

    Breaking the rules: Reversal of the high Markovnikov selectivity of Wacker-type oxidations was accomplished using a nitrite co-catalyst. Unbiased aliphatic alkenes can be oxidized with high yield and aldehyde selectivity, and several functional groups are tolerated. 18O-labeling experiments indicate that the aldehydic O atom is derived from the nitrite salt.

  17. Selective Production of Aromatic Aldehydes from Heavy Fraction of Bio-oil via Catalytic Oxidation

    International Nuclear Information System (INIS)

    High value-added aromatic aldehydes (e. g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide (H2O2) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin (Co(TPPS4)) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without Co(TPPS4). Moreover, a possible mechanism of HFBO oxidation using Co(TPPS4)/H2O2 was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under Co(TPPS4)/H2O2 system

  18. Size-Selective Oxidation of Aldehydes with Zeolite Encapsulated Gold Nanoparticles

    DEFF Research Database (Denmark)

    Højholt, Karen Thrane; Laursen, Anders Bo; Kegnæs, Søren;

    2011-01-01

    Here, we report a synthesis and catalytic study of hybrid materials comprised of 1–3 nm sinter-stable Au nanoparticles in MFI-type zeolites. An optional post-treatment in aqua regia effectively remove Au from the external surfaces. The size-selective aerobic aldehyde oxidation verifies...

  19. Pulsed corona discharge oxidation of aqueous lignin: decomposition and aldehydes formation.

    Science.gov (United States)

    Panorel, Iris; Kaijanen, Laura; Kornev, Iakov; Preis, Sergei; Louhi-Kultanen, Marjatta; Sirén, Heli

    2014-01-01

    Lignin is the mass waste product of pulp and paper industry mostly incinerated for energy recovery. Lignin is, however, a substantial source of raw material for derivatives currently produced in costly wet oxidation processes. The pulsed corona discharge (PCD) for the first time was applied to lignin oxidation aiming a cost-effective environmentally friendly lignin removal and transformation to aldehydes. The experimental research into treatment of coniferous kraft lignin aqueous solutions was undertaken to establish the dependence of lignin oxidation and aldehyde formation on the discharge parameters, initial concentration of lignin and gas phase composition. The rate and the energy efficiency of lignin oxidation increased with increasing oxygen concentration reaching up to 82 g kW-1 h-1 in 89% vol. oxygen. Oxidation energy efficiency in PCD treatment exceeds the one for conventional ozonation by the factor of two under the experimental conditions. Oxidation at low oxygen concentrations showed a tendency of the increasing aldehydes and glyoxylic acid formation yield. PMID:24600854

  20. Aldehyde Selective Wacker Oxidations of Phthalimide Protected Allylic Amines : A New Catalytic Route to beta(3)-Amino Acids

    NARCIS (Netherlands)

    Weiner, Barbara; Baeza Garcia, Alejandro; Jerphagnon, Thomas; Feringa, Ben L.

    2009-01-01

    A new method for the synthesis of B-3-amino acids is presented. Phthalimide protected allylic amines are oxidized under Wacker conditions selectively to aldehydes using PdCl2 and CuCl or Pd(MeCN)(2)Cl(NO2) and CuCl2 as complementary catalyst systems. The aldehydes are produced in excellent yields an

  1. Mesenchymal Stem/Stromal Cells Derived From a Reproductive Tissue Niche Under Oxidative Stress Have High Aldehyde Dehydrogenase Activity.

    Science.gov (United States)

    Kusuma, Gina D; Abumaree, Mohamed H; Pertile, Mark D; Perkins, Anthony V; Brennecke, Shaun P; Kalionis, Bill

    2016-06-01

    The use of mesenchymal stem/stromal cells (MSC) in regenerative medicine often requires MSC to function in environments of high oxidative stress. Human pregnancy is a condition where the mother's tissues, and in particular her circulatory system, are exposed to increased levels of oxidative stress. MSC in the maternal decidua basalis (DMSC) are in a vascular niche, and thus would be exposed to oxidative stress products in the maternal circulation. Aldehyde dehydrogenases (ALDH) are a large family of enzymes which detoxify aldehydes and thereby protect stem cells against oxidative damage. A subpopulation of MSC express high levels of ALDH (ALDH(br)) and these are more potent in repairing and regenerating tissues. DMSC was compared with chorionic villous MSC (CMSC) derived from the human placenta. CMSC reside in vascular niche and are exposed to the fetal circulation, which is in lower oxidative state. We screened an ALDH isozyme cDNA array and determined that relative to CMSC, DMSC expressed high levels of ALDH1 family members, predominantly ALDH1A1. Immunocytochemistry gave qualitative confirmation at the protein level. Immunofluorescence detected ALDH1 immunoreactivity in the DMSC and CMSC vascular niche. The percentage of ALDH(br) cells was calculated by Aldefluor assay and DMSC showed a significantly higher percentage of ALDH(br) cells than CMSC. Finally, flow sorted ALDH(br) cells were functionally potent in colony forming unit assays. DMSC, which are derived from pregnancy tissues that are naturally exposed to high levels of oxidative stress, may be better candidates for regenerative therapies where MSC must function in high oxidative stress environments. PMID:26880140

  2. Selective Production of Aromatic Aldehydes from Heavy Fraction of Bio-oil via Catalytic Oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yan; Chang, Jie; Ouyang, Yong; Zheng, Xianwei [South China Univ. of Technology, Guangzhou (China)

    2014-06-15

    High value-added aromatic aldehydes (e. g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide (H{sub 2}O{sub 2}) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin (Co(TPPS{sub 4})) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without Co(TPPS{sub 4}). Moreover, a possible mechanism of HFBO oxidation using Co(TPPS{sub 4})/H{sub 2}O{sub 2} was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under Co(TPPS{sub 4})/H{sub 2}O{sub 2} system.

  3. [Health effect of volatile aldehyde compounds in photocatalytic oxidation of aromatics compounds].

    Science.gov (United States)

    Zhao, Wei-rong; Liao, Qiu-wen; Yang, Ya-nan; Dai, Jiu-song

    2013-05-01

    Photocatalytic oxidation (PCO) of toluene and benzaldehyde in indoor air by N doped TiO2 (N-TiO2) was conducted under UV irradiation of 254 nm. The intermediates were identified and monitored on real-time by proton transfer reaction-mass spectrometry. The health risks of PCO of toluene and benzaldehyde were assessed based on health risk influence index (eta). Results indicated that both the conversion rate and mineralization rate of toluene and benzaldehyde were relatively high, however, the volatile aldehyde compounds (VAs), including acetaldehyde and formaldehyde generated from ring-opening, significantly influenced the health risks of PCO of toluene and benzaldehyde. Acetaldehyde played a crucial role on health risks, which was inclined to desorb from the surface of catalysts, accumulate in gas-phase, and increase the health risks of PCO of the aromatic compounds. The concentration of formaldehyde kept stable at a relatively low level, however its impact cannot be neglected. In the PCO process of toluene and benzaldehyde, eta reached the maximum values of 8 499.68 and 21.43, with the eta(VAs), contribution of VAs to the health risk influence index of outlet, reaching 99.3% and 98.3%, respectively. The average values of eta in the PCO process of 30 min were 932.86 and 8.52, and for which eta(VAs), reached 98.5% and 98.0%, respectively. When PCO of toluene and benzaldehyde reached steady state, eta were 236.09 and 2.30, and eta(VAs) reached 97.9% and 97.8%, respectively. Hence, eta(VAs), can be taken as a characteristic parameter in assessment of health risks of PCO of aromatic compounds.

  4. Oxidation of N-Nitrosoalkylamines by human cytochrome P450 2A6: sequential oxidation to aldehydes and carboxylic acids and analysis of reaction steps.

    Science.gov (United States)

    Chowdhury, Goutam; Calcutt, M Wade; Guengerich, F Peter

    2010-03-12

    Cytochrome P450 (P450) 2A6 activates nitrosamines, including N,N-dimethylnitrosamine (DMN) and N,N-diethylnitrosamine (DEN), to alkyl diazohydroxides (which are DNA-alkylating agents) and also aldehydes (HCHO from DMN and CH(3)CHO from DEN). The N-dealkylation of DMN had a high intrinsic kinetic deuterium isotope effect ((D)k(app) approximately 10), which was highly expressed in a variety of competitive and non-competitive experiments. The (D)k(app) for DEN was approximately 3 and not expressed in non-competitive experiments. DMN and DEN were also oxidized to HCO(2)H and CH(3)CO(2)H, respectively. In neither case was a lag observed, which was unexpected considering the k(cat) and K(m) parameters measured for oxidation of DMN and DEN to the aldehydes and for oxidation of the aldehydes to the carboxylic acids. Spectral analysis did not indicate strong affinity of the aldehydes for P450 2A6, but pulse-chase experiments showed only limited exchange with added (unlabeled) aldehydes in the oxidations of DMN and DEN to carboxylic acids. Substoichiometric kinetic bursts were observed in the pre-steady-state oxidations of DMN and DEN to aldehydes. A minimal kinetic model was developed that was consistent with all of the observed phenomena and involves a conformational change of P450 2A6 following substrate binding, equilibrium of the P450-substrate complex with a non-productive form, and oxidation of the aldehydes to carboxylic acids in a process that avoids relaxation of the conformation following the first oxidation (i.e. of DMN or DEN to an aldehyde). PMID:20061389

  5. Catalytic wet-air oxidation of lignin in a three-phase reactor with aromatic aldehyde production

    Directory of Open Access Journals (Sweden)

    Sales F.G.

    2004-01-01

    Full Text Available In the present work a process of catalytic wet air oxidation of lignin obtained from sugar-cane bagasse is developed with the objective of producing vanillin, syringaldehyde and p-hydroxybenzaldehyde in a continuous regime. Palladium supported on g-alumina was used as the catalyst. The reactions in the lignin degradation and aldehyde production were described by a kinetic model as a system of complex parallel and series reactions, in which pseudo-first-order steps are found. For the purpose of producing aromatic aldehydes in continuous regime, a three-phase fluidized reactor was built, and it was operated using atmospheric air as the oxidizer. The best yield in aromatic aldehydes was of 12%. The experimental results were compatible with those values obtained by the pseudo-heterogeneous axial dispersion model (PHADM applied to the liquid phase.

  6. Oxidation of N-alkyl and N-aryl azaheterocycles by free and immobilized rabbit liver aldehyde oxidase

    NARCIS (Netherlands)

    Angelino, S.A.G.F.

    1984-01-01

    Aldehyde oxidase isolated from rabbit liver is studied in this thesis with regard to its application in organic synthesis. The enzyme has a broad substrate specificity towards azaheterocycles and therefore offers great potential for profitable use.The oxidation of 1-alkyl(aryl)-3-aminocarbonylpyridi

  7. Aerobic oxidation of benzylic aldehydes to acids catalyzed by iron (Ⅲ) meso-tetraphenylporphyrin chloride under ambient conditions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Highly efficient aerobic oxidation of benzylic aldehydes to the corresponding acids catalyzed by iron (Ⅲ) meso-tetraphenylporphyrin chloride (Fe(TPP)Cl) under ambient conditions was developed. The catalyst has been proved to be an excellent catalyst for the system in the presence of molecular oxygen and isobutryaldehyde at room temperature.

  8. Aldehyde dehydrogenase 2 protects human umbilical vein endothelial cells against oxidative damage and increases endothelial nitric oxide production to reverse nitroglycerin tolerance.

    Science.gov (United States)

    Hu, X Y; Fang, Q; Ma, D; Jiang, L; Yang, Y; Sun, J; Yang, C; Wang, J S

    2016-06-10

    Medical nitroglycerin (glyceryl trinitrate, GTN) use is limited principally by tolerance typified by a decrease in nitric oxide (NO) produced by biotransformation. Such tolerance may lead to endothelial dysfunction by inducing oxidative stress. In vivo studies have demonstrated that aldehyde dehydrogenase 2 (ALDH2) plays important roles in GTN biotransformation and tolerance. Thus, modification of ALDH2 expression represents a potentially effective strategy to prevent and reverse GTN tolerance and endothelial dysfunction. In this study, a eukaryotic expression vector containing the ALDH2 gene was introduced into human umbilical vein endothelial cells (HUVECs) by liposome-mediated transfection. An indirect immunofluorescence assay showed that ALDH2 expression increased 24 h after transfection. Moreover, real-time polymerase chain reaction and western blotting revealed significantly higher ALDH2 mRNA and protein expression in the gene-transfected group than in the two control groups. GTN tolerance was induced by treating HUVECs with 10 mM GTN for 16 h + 10 min, which significantly decreased NO levels in control cells, but not in those transfected with ALDH2. Overexpression of ALDH2 increased cell survival against GTN-induced cytotoxicity and conferred protection from oxidative damage resulting from nitrate tolerance, accompanied by decreased production of intracellular reactive oxygen species and reduced expression of heme oxygenase 1. Furthermore, ALDH2 overexpression promoted Akt phosphorylation under GTN tolerance conditions. ALDH2 gene transfection can reverse and prevent tolerance to GTN through its bioactivation and protect against oxidative damage, preventing the development of endothelial dysfunction.

  9. Detoxification of aldehydes by histidine-containing dipeptides: from chemistry to clinical implications

    OpenAIRE

    Xie, Zhengzhi; Baba, Shahid P.; Sweeney, Brooke R.; Barski, Oleg A.

    2013-01-01

    Aldehydes are generated by oxidized lipids and carbohydrates at increased levels under conditions of metabolic imbalance and oxidative stress during atherosclerosis, myocardial and cerebral ischemia, diabetes, neurodegenerative diseases and trauma. In most tissues, aldehydes are detoxified by oxidoreductases that catalyze the oxidation or the reduction of aldehydes or enzymatic and nonenzymatic conjugation with low molecular weight thiols and amines, such as glutathione and histidine dipeptid...

  10. One-pot synthesis of amides by aerobic oxidative coupling of alcohols or aldehydes with amines using supported gold and base as catalysts

    DEFF Research Database (Denmark)

    Kegnæs, Søren; Mielby, Jerrik Jørgen; Mentzel, Uffe Vie;

    2012-01-01

    Synthesis of amides by aerobic oxidative coupling of alcohols or aldehydes with amines via intermediate formation of methyl esters is highly efficient and selective when using a catalytic system comprised of supported gold nanoparticles and added base in methanol.......Synthesis of amides by aerobic oxidative coupling of alcohols or aldehydes with amines via intermediate formation of methyl esters is highly efficient and selective when using a catalytic system comprised of supported gold nanoparticles and added base in methanol....

  11. The Effect of Polyunsaturated Aldehydes on Skeletonema marinoi (Bacillariophyceae: The Involvement of Reactive Oxygen Species and Nitric Oxide

    Directory of Open Access Journals (Sweden)

    Alessandra A. Gallina

    2014-07-01

    Full Text Available Nitric oxide (NO and reactive oxygen species (ROS production was investigated in the marine diatom, Skeletonema marinoi (SM, exposed to 2E,4E/Z-decadienal (DECA, 2E,4E/Z-octadienal (OCTA, 2E,4E/Z-heptadienal (HEPTA and a mix of these last two (MIX. When exposed to polyunsaturated aldehydes (PUA, a decrease of NO was observed, proportional to the PUA concentration (85% of the initial level after 180 min with 66 µM DECA. Only OCTA, HEPTA and MIX induced a parallel increase of ROS, the highest (2.9-times the control with OCTA concentrations twice the EC50 for growth at 24 h (20 μM. The synthesis of carotenoids belonging to the xanthophyll cycle (XC was enhanced during exposure, suggesting their antioxidant activity. Our data provide evidence that specific pathways exist as a reaction to PUA and that they depend upon the PUA used and/or the diatom species. In fact, Phaeodactylum tricornutum (PT produces NO in response to DECA, but not to OCTA. We advance the hypothesis that SM perceives OCTA and HEPTA as intra-population infochemicals (as it produces PUA, while PT (non-PUA producing species perceives them as allelochemicals. The ability to produce and to use PUA as infochemicals may underlie ecological traits of different diatom species and modulate ecological success in natural communities.

  12. Catalytic wet-air oxidation of lignin in a three-phase reactor with aromatic aldehyde production

    OpenAIRE

    Sales F.G.; Abreu C.A.M.; Pereira J. A. F. R.

    2004-01-01

    In the present work a process of catalytic wet air oxidation of lignin obtained from sugar-cane bagasse is developed with the objective of producing vanillin, syringaldehyde and p-hydroxybenzaldehyde in a continuous regime. Palladium supported on g-alumina was used as the catalyst. The reactions in the lignin degradation and aldehyde production were described by a kinetic model as a system of complex parallel and series reactions, in which pseudo-first-order steps are found. For the purpose o...

  13. Copper-catalyzed oxidative amidation of aldehydes with amine salts: synthesis of primary, secondary, and tertiary amides.

    Science.gov (United States)

    Ghosh, Subhash Chandra; Ngiam, Joyce S Y; Seayad, Abdul M; Tuan, Dang Thanh; Chai, Christina L L; Chen, Anqi

    2012-09-21

    A practical method for the amidation of aldehydes with economic ammonium chloride or amine hydrochloride salts has been developed for the synthesis of a wide variety of amides by using inexpensive copper sulfate or copper(I) oxide as a catalyst and aqueous tert-butyl hydroperoxide as an oxidant. This amidation reaction is operationally straightforward and provides primary, secondary, and tertiary amides in good to excellent yields for most cases utilizing inexpensive and readily available reagents under mild conditions. In situ formation of amine salts from free amines extends the substrate scope of the reaction. Chiral amides are also synthesized from their corresponding chiral amines without detectable racemization. The practicality of this amide formation reaction has been demonstrated in an efficient synthesis of the antiarrhythmic drug N-acetylprocainamide. PMID:22894712

  14. Quantification of the 2-deoxyribonolactone and nucleoside 5'-aldehyde products of 2-deoxyribose oxidation in DNA and cells by isotope-dilution gas chromatography mass spectrometry: differential effects of gamma-radiation and Fe2+-EDTA.

    Science.gov (United States)

    Chan, Wan; Chen, Bingzi; Wang, Lianrong; Taghizadeh, Koli; Demott, Michael S; Dedon, Peter C

    2010-05-01

    The oxidation of 2-deoxyribose in DNA has emerged as a critical determinant of the cellular toxicity of oxidative damage to DNA, with oxidation of each carbon producing a unique spectrum of electrophilic products. We have developed and validated an isotope-dilution gas chromatography-coupled mass spectrometry (GC-MS) method for the rigorous quantification of two major 2-deoxyribose oxidation products: the 2-deoxyribonolactone abasic site of 1'-oxidation and the nucleoside 5'-aldehyde of 5'-oxidation chemistry. The method entails elimination of these products as 5-methylene-2(5H)-furanone (5MF) and furfural, respectively, followed by derivatization with pentafluorophenylhydrazine (PFPH), addition of isotopically labeled PFPH derivatives as internal standards, extraction of the derivatives, and quantification by GC-MS analysis. The precision and accuracy of the method were validated with oligodeoxynucleotides containing the 2-deoxyribonolactone and nucleoside 5'-aldehyde lesions. Further, the well-defined 2-deoxyribose oxidation chemistry of the enediyne antibiotics, neocarzinostatin and calicheamicin gamma(1)(I), was exploited in control studies, with neocarzinostatin producing 10 2-deoxyribonolactone and 300 nucleoside 5'-aldehyde per 10(6) nt per microM in accord with its established minor 1'- and major 5'-oxidation chemistry. Calicheamicin unexpectedly caused 1'-oxidation at a low level of 10 2-deoxyribonolactone per 10(6) nt per microM in addition to the expected predominance of 5'-oxidation at 560 nucleoside 5'-aldehyde per 10(6) nt per microM. The two hydroxyl radical-mediated DNA oxidants, gamma-radiation and Fe(2+)-EDTA, produced nucleoside 5'-aldehyde at a frequency of 57 per 10(6) nt per Gy (G-value 74 nmol/J) and 3.5 per 10(6) nt per microM, respectively, which amounted to 40% and 35%, respectively, of total 2-deoxyribose oxidation as measured by a plasmid nicking assay. However, gamma-radiation and Fe(2+)-EDTA produced different proportions of 2

  15. Acrolein, a highly toxic aldehyde generated under oxidative stress in vivo, aggravates the mouse liver damage after acetaminophen overdose.

    Science.gov (United States)

    Arai, Tomoya; Koyama, Ryo; Yuasa, Makoto; Kitamura, Daisuke; Mizuta, Ryushin

    2014-01-01

    Although acetaminophen-induced liver injury in mice has been extensively studied as a model of human acute drug-induced hepatitis, the mechanism of liver injury remains unclear. Liver injury is believed to be initiated by metabolic conversion of acetaminophen to the highly reactive intermediate N-acetyl p-benzoquinoneimine, and is aggravated by subsequent oxidative stress via reactive oxygen species (ROS), including hydrogen peroxide (H2O2) and the hydroxyl radical (•OH). In this study, we found that a highly toxic unsaturated aldehyde acrolein, a byproduct of oxidative stress, has a major role in acetaminophen-induced liver injury. Acetaminophen administration in mice resulted in liver damage and increased acrolein-protein adduct formation. However, both of them were decreased by treatment with N-acetyl-L-cysteine (NAC) or sodium 2-mercaptoethanesulfonate (MESNA), two known acrolein scavengers. The specificity of NAC and MESNA was confirmed in cell culture, because acrolein toxicity, but not H2O2 or •OH toxicity, was inhibited by NAC and MESNA. These results suggest that acrolein may be more strongly correlated with acetaminophen-induced liver injury than ROS, and that acrolein produced by acetaminophen-induced oxidative stress can spread from dying cells at the primary injury site, causing damage to the adjacent cells and aggravating liver injury.

  16. CuO and Ag2O/CuO Catalyzed Oxidation of Aldehydes to the Corresponding Carboxylic Acids by Molecular Oxygen

    Directory of Open Access Journals (Sweden)

    Yaowu Sha

    2008-04-01

    Full Text Available Furfural was oxidized to furoic acid by molecular oxygen under catalysis by 150nm-sized Ag2O/CuO (92% or simply CuO (86.6%. When 30 nm-size catalyst was used,the main product was a furfural Diels-Alder adduct. Detailed reaction conditions andregeneration of catalysts were investigated. Under optimal conditions, a series of aromaticand aliphatic aldehydes were oxidized to the corresponding acids in good yields.

  17. A biphasic oxidation of alcohols to aldehydes and ketones using a simplified packed-bed microreactor

    OpenAIRE

    Andrew Bogdan; D. Tyler McQuade

    2009-01-01

    We demonstrate the preparation and characterization of a simplified packed-bed microreactor using an immobilized TEMPO catalyst shown to oxidize primary and secondary alcohols via the biphasic Anelli-Montanari protocol. Oxidations occurred in high yields with great stability over time. We observed that plugs of aqueous oxidant and organic alcohol entered the reactor as plugs but merged into an emulsion on the packed-bed. The emulsion coalesced into larger plugs upon exiting the reactor, leavi...

  18. A biphasic oxidation of alcohols to aldehydes and ketones using a simplified packed-bed microreactor

    Directory of Open Access Journals (Sweden)

    Andrew Bogdan

    2009-04-01

    Full Text Available We demonstrate the preparation and characterization of a simplified packed-bed microreactor using an immobilized TEMPO catalyst shown to oxidize primary and secondary alcohols via the biphasic Anelli-Montanari protocol. Oxidations occurred in high yields with great stability over time. We observed that plugs of aqueous oxidant and organic alcohol entered the reactor as plugs but merged into an emulsion on the packed-bed. The emulsion coalesced into larger plugs upon exiting the reactor, leaving the organic product separate from the aqueous by-products. Furthermore, the microreactor oxidized a wide range of alcohols and remained active in excess of 100 trials without showing any loss of catalytic activity.

  19. Effect of different solvent on the photocatalytic activity of ZnIn2S4 for selective oxidation of aromatic alcohols to aromatic aldehydes under visible light irradiation

    Science.gov (United States)

    Su, Li; Ye, Xiangju; Meng, Sugang; Fu, Xianliang; Chen, Shifu

    2016-10-01

    A series of ternary chalcogenides, zinc indium sulphide (ZnIn2S4), were synthesized by a simple solvothermal method with different solvents. The structure, textural, and optical properties of the resulting materials were thoroughly characterized by several techniques. The as-prepared ZnIn2S4 samples could all be employed as excellent photocatalysts to activate O2 for selective oxidation of aromatic alcohols to aromatic aldehydes under visible light illumination. The results showed that ZnIn2S4 prepared in ethanol solvent (ZIS-EtOH) exhibited the highest photocatalytic activity among the screened samples. The differences of photocatalytic performance for ZnIn2S4 samples prepared in different media were mainly attributed to the different levels of exposed {0001} special facets caused by the exposure extent of the basic crystal plane. In addition, rad O2- and positive holes were proved to be the main active species during the photocatalytic process. Combined with the previous reports, a possible photocatalytic mechanism for the selective oxidation of benzyl alcohol to benzaldehyde over ZnIn2S4 sample was proposed.

  20. CuCl-Catalyzed Aerobic Oxidation of Allylic and Propargylic Alcohols to Aldehydes or Ketones with 1 : 1 Combination of Phenanthroline and Bipyridine as the Ligandst%CuCl-Catalyzed Aerobic Oxidation of Allylic and Propargylic Alcohols to Aldehydes or Ketones with 1 : 1 Combination of Phenanthroline and Bipyridine as the Ligandst

    Institute of Scientific and Technical Information of China (English)

    刘宇; 麻生明

    2012-01-01

    We developed a modified protocol for the oxidation of 2,3-allenyl alcohols using CuCI with l : 1 combination of phenanthroline and bipyridine as the catalyst. To further investigate the applicability of this system, other types of alcohols such as allylic and propargylic alcohols have been tested: we found that both allylic and propargylic alcohols may be oxidized to the corresponding aldehydes or ketones using molecular oxygen in air as the oxidant with moderate to excellent yields.

  1. Enzyme-inspired functional surfactant for aerobic oxidation of activated alcohols to aldehydes in water

    KAUST Repository

    Chen, Batian

    2015-02-06

    We describe an enzyme-inspired catalytic system based on a rationally designed multifunctional amphiphile. The resulting micelles feature metal-binding sites and stable free radical moieties as well as fluorous pockets that attract and preconcentrate molecular oxygen. In the presence of copper ions, the micelles effect chemoselective aerobic alcohol oxidation under ambient conditions in water, a transformation that is challenging to achieve nonenzymatically.

  2. Formation of gold clusters on La-Ni mixed oxides and its catalytic performance for isomerization of allylic alcohols to saturated aldehydes

    International Nuclear Information System (INIS)

    Au/NiO catalyzed the isomerization of allylic alcohols to afford saturated aldehydes. La-Ni mixed oxide could stabilize Au(III) and afford gold clusters smaller than 1 nm by H2 reduction. The resulting Au clusters on La-Ni-O exhibited superior catalytic performance to Au/NiO for the isomerization of internal allylic alcohol, 2-octen-1-ol to octanal. (author)

  3. Isolated tumoral pyruvate dehydrogenase can synthesize acetoin which inhibits pyruvate oxidation as well as other aldehydes.

    Science.gov (United States)

    Baggetto, L G; Lehninger, A L

    1987-05-29

    Oxidation of 1 mM pyruvate by Ehrlich and AS30-D tumor mitochondria is inhibited by acetoin, an unusual and important metabolite of pyruvate utilization by cancer cells, by acetaldehyde, methylglyoxal and excess pyruvate. The respiratory inhibition is reversed by other substrates added to pyruvate and also by 0.5 mM ATP. Kinetic properties of pyruvate dehydrogenase complex isolated from these tumor mitochondria have been studied. This complex appears to be able to synthesize acetoin from acetaldehyde plus pyruvate and is competitively inhibited by acetoin. The role of a new regulatory pattern for tumoral pyruvate dehydrogenase is presented.

  4. Isolated tumoral pyruvate dehydrogenase can synthesize acetoin which inhibits pyruvate oxidation as well as other aldehydes.

    Science.gov (United States)

    Baggetto, L G; Lehninger, A L

    1987-05-29

    Oxidation of 1 mM pyruvate by Ehrlich and AS30-D tumor mitochondria is inhibited by acetoin, an unusual and important metabolite of pyruvate utilization by cancer cells, by acetaldehyde, methylglyoxal and excess pyruvate. The respiratory inhibition is reversed by other substrates added to pyruvate and also by 0.5 mM ATP. Kinetic properties of pyruvate dehydrogenase complex isolated from these tumor mitochondria have been studied. This complex appears to be able to synthesize acetoin from acetaldehyde plus pyruvate and is competitively inhibited by acetoin. The role of a new regulatory pattern for tumoral pyruvate dehydrogenase is presented. PMID:3593337

  5. Isolation of an Aldehyde Dehydrogenase Involved in the Oxidation of Fluoroacetaldehyde to Fluoroacetate in Streptomyces cattleya

    Science.gov (United States)

    Murphy, Cormac D.; Moss, Steven J.; O'Hagan, David

    2001-01-01

    Streptomyces cattleya is unusual in that it produces fluoroacetate and 4-fluorothreonine as secondary metabolites. We now report the isolation of an NAD+-dependent fluoroacetaldehyde dehydrogenase from S. cattleya that mediates the oxidation of fluoroacetaldehyde to fluoroacetate. This is the first enzyme to be identified that is directly involved in fluorometabolite biosynthesis. Production of the enzyme begins in late exponential growth and continues into the stationary phase. Measurement of kinetic parameters shows that the enzyme has a high affinity for fluoroacetaldehyde and glycoaldehyde, but not acetaldehyde. PMID:11571203

  6. Wet Aerobic Oxidation of Lignin into Aromatic Aldehydes Catalysed by a Perovskite-type Oxide: LaFe1-xCuxO3 (x=0, 0.1, 0.2

    Directory of Open Access Journals (Sweden)

    Lu Lin

    2009-07-01

    Full Text Available The perovskite-type oxide catalyst LaFe1-xCuxO3 (x=0, 0.1, 0.2 was prepared by the sol–gel method, and tested as a catalyst in the wet aerobic oxidation (WAO of lignin into aromatic aldehydes. The lignin conversion and the yield of each aromatic aldehyde were significantly enhanced in the catalytic process, compared with the non-catalyzed process. Moreover, it was shown that the stability of activity and structure of LaFe1-xCuxO3 (x=0, 0.1, 0.2 remained nearly unchanged after a series of successive recyclings of the catalytic reactions, indicating it was an efficient and recyclable heterogeneous catalyst for the conversion of lignin into aromatic aldehydes in the WAO process.

  7. Distinct expression levels and patterns of stem cell marker, aldehyde dehydrogenase isoform 1 (ALDH1, in human epithelial cancers.

    Directory of Open Access Journals (Sweden)

    Shan Deng

    Full Text Available Aldehyde dehydrogenase isoform 1 (ALDH1 has been proved useful for the identification of cancer stem cells. However, our knowledge of the expression and activity of ALDH1 in common epithelial cancers and their corresponding normal tissues is still largely absent. Therefore, we characterized ALDH1 expression in 24 types of normal tissues and a large collection of epithelial tumor specimens (six cancer types, n = 792 by immunohistochemical staining. Using the ALDEFUOR assay, ALDH1 activity was also examined in 16 primary tumor specimens and 43 established epithelial cancer cell lines. In addition, an ovarian cancer transgenic mouse model and 7 murine ovarian cancer cell lines were analyzed. We found that the expression levels and patterns of ALDH1 in epithelial cancers are remarkably distinct, and they correlate with their corresponding normal tissues. ALDH1 protein expression levels are positively correlated with ALDH1 enzymatic activity measured by ALDEFLUOR assay. Long-term in vitro culture doesn't significantly affect ALDH1 activity in epithelial tumor cells. Consistent with research on other cancers, we found that high ALDH1 expression is significantly associated with poor clinical outcomes in serous ovarian cancer patients (n = 439, p = 0.0036. Finally, ALDH(br tumor cells exhibit cancer stem cell properties and are resistant to chemotherapy. As a novel cancer stem cell marker, ALDH1 can be used for tumors whose corresponding normal tissues express ALDH1 in relatively restricted or limited levels such as breast, lung, ovarian or colon cancer.

  8. Novel oxidation of aromatic aldehydes catalyzed by Preyssler's anion, [NaP{sub 5}W{sub 30}O{sub 110}]{sup 14-}

    Energy Technology Data Exchange (ETDEWEB)

    Bamoharram, F.F.; Roshani, M.; Moghayadi, M. [Islamic Azad University-Mashhad Branch, Mashhad (Iran, Islamic Republic of). Dept. of Chemistry]. E-mail: abamoharram@yahoo.com; Alizadeh, M.H. [Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of). Dept. of Chemistry; Razavi, H. [Georgetown University, Washington, DC (United States). Dept. of Chemistry

    2006-05-15

    Preyssler's anion, with formula [NaP{sub 5}W{sub 30}O{sub 110}]{sup 14-}, catalyzes the oxidation of aromatic aldehydes to related carboxylic acids by hydrogen peroxide as oxidizing agent, under microwave irradiation, or at 70 deg C. Both homogeneous and heterogeneous Preyssler's catalysts (as H{sub 14}[NaP{sub 5}W{sub 30}O{sub 110}]) were used and had their activity compared with those of some Keggin structures. Our data indicate that Sodium30-tungsto pentaphosphate, the so-called Preyssler's anion, with high hydrolytic (pH=0-12) and thermal stability is the best catalyst with high yield and good selectivity. Under microwave irradiation, this polyanion supported on SiO{sub 2} was found to be an excellent catalyst for aldehydes with low loss factor in 1-2 min (the loss factor is a measure of the ability of the material to dissipate energy). The effects of various parameters, including catalyst type, nature of the substituent in the aldehyde and temperature, on the yield of the carboxylic acids were studied. (author)

  9. Solvent-free oxidation of aldehydes to acids by TBHP using environmental-friendly MnO$^{−1}_{4}$-exchanged Mg-Al hydrotalcite catalyst

    Indian Academy of Sciences (India)

    Vasant R Choudhary; Deepa K Dumbre; Vijay S Narkhede

    2012-07-01

    A number of hydrotalcite (Mg-Al, Mn-Al, Co-Al, Ni-Al, Mg-Fe, Mg-Cr and Cu-Al) catalysts, with or without MnO$^{−1}_{4}$-exchange, were evaluated for their performance in the solvent-free oxidation of benzaldehyde to benzoic acid by tert-butyl hydroperoxide under reflux in the absence of any solvent. The MnO$^{−1}_{4}$-exchanged Mg-Al-hydrotalcite (Mg/Al = 10) showed high activity in the oxidation of different aromatic and aliphatic aldehydes to their corresponding acids and also showed excellent reusability in the oxidation process which is environmental-friendly.

  10. Formation of Aldehyde and Ketone Compounds during Production and Storage of Milk Powder

    OpenAIRE

    Weijun Wang; Lanwei Zhang; Yanhua Li

    2012-01-01

    Certain aldehyde and ketone compounds can be used as indicators, at a molecular level, of the oxidized flavor of milk powder instead of sensory evaluation. This study investigated the formation of aldehyde and ketone compounds as affected by the heat-related processing and storage of milk powder. The compounds were extracted by solid phase microextraction fiber and determined using gas chromatography-mass spectrometry. In the results, higher contents of hexanal, 2-heptanone, octanal and 3-oct...

  11. The oxidative fermentation of ethanol in Gluconacetobacter diazotrophicus is a two-step pathway catalyzed by a single enzyme: alcohol-aldehyde Dehydrogenase (ADHa).

    Science.gov (United States)

    Gómez-Manzo, Saúl; Escamilla, José E; González-Valdez, Abigail; López-Velázquez, Gabriel; Vanoye-Carlo, América; Marcial-Quino, Jaime; de la Mora-de la Mora, Ignacio; Garcia-Torres, Itzhel; Enríquez-Flores, Sergio; Contreras-Zentella, Martha Lucinda; Arreguín-Espinosa, Roberto; Kroneck, Peter M H; Sosa-Torres, Martha Elena

    2015-01-01

    Gluconacetobacter diazotrophicus is a N2-fixing bacterium endophyte from sugar cane. The oxidation of ethanol to acetic acid of this organism takes place in the periplasmic space, and this reaction is catalyzed by two membrane-bound enzymes complexes: the alcohol dehydrogenase (ADH) and the aldehyde dehydrogenase (ALDH). We present strong evidence showing that the well-known membrane-bound Alcohol dehydrogenase (ADHa) of Ga. diazotrophicus is indeed a double function enzyme, which is able to use primary alcohols (C2-C6) and its respective aldehydes as alternate substrates. Moreover, the enzyme utilizes ethanol as a substrate in a reaction mechanism where this is subjected to a two-step oxidation process to produce acetic acid without releasing the acetaldehyde intermediary to the media. Moreover, we propose a mechanism that, under physiological conditions, might permit a massive conversion of ethanol to acetic acid, as usually occurs in the acetic acid bacteria, but without the transient accumulation of the highly toxic acetaldehyde. PMID:25574602

  12. The Oxidative Fermentation of Ethanol in Gluconacetobacter diazotrophicus Is a Two-Step Pathway Catalyzed by a Single Enzyme: Alcohol-Aldehyde Dehydrogenase (ADHa

    Directory of Open Access Journals (Sweden)

    Saúl Gómez-Manzo

    2015-01-01

    Full Text Available Gluconacetobacter diazotrophicus is a N2-fixing bacterium endophyte from sugar cane. The oxidation of ethanol to acetic acid of this organism takes place in the periplasmic space, and this reaction is catalyzed by two membrane-bound enzymes complexes: the alcohol dehydrogenase (ADH and the aldehyde dehydrogenase (ALDH. We present strong evidence showing that the well-known membrane-bound Alcohol dehydrogenase (ADHa of Ga. diazotrophicus is indeed a double function enzyme, which is able to use primary alcohols (C2–C6 and its respective aldehydes as alternate substrates. Moreover, the enzyme utilizes ethanol as a substrate in a reaction mechanism where this is subjected to a two-step oxidation process to produce acetic acid without releasing the acetaldehyde intermediary to the media. Moreover, we propose a mechanism that, under physiological conditions, might permit a massive conversion of ethanol to acetic acid, as usually occurs in the acetic acid bacteria, but without the transient accumulation of the highly toxic acetaldehyde.

  13. Alcohol, Aldehydes, Adducts and Airways.

    Science.gov (United States)

    Sapkota, Muna; Wyatt, Todd A

    2015-11-05

    Drinking alcohol and smoking cigarettes results in the formation of reactive aldehydes in the lung, which are capable of forming adducts with several proteins and DNA. Acetaldehyde and malondialdehyde are the major aldehydes generated in high levels in the lung of subjects with alcohol use disorder who smoke cigarettes. In addition to the above aldehydes, several other aldehydes like 4-hydroxynonenal, formaldehyde and acrolein are also detected in the lung due to exposure to toxic gases, vapors and chemicals. These aldehydes react with nucleophilic targets in cells such as DNA, lipids and proteins to form both stable and unstable adducts. This adduction may disturb cellular functions as well as damage proteins, nucleic acids and lipids. Among several adducts formed in the lung, malondialdehyde DNA (MDA-DNA) adduct and hybrid malondialdehyde-acetaldehyde (MAA) protein adducts have been shown to initiate several pathological conditions in the lung. MDA-DNA adducts are pre-mutagenic in mammalian cells and induce frame shift and base-pair substitution mutations, whereas MAA protein adducts have been shown to induce inflammation and inhibit wound healing. This review provides an insight into different reactive aldehyde adducts and their role in the pathogenesis of lung disease.

  14. Pyruvate:ferredoxin oxidoreductase and bifunctional aldehyde-alcohol dehydrogenase are essential for energy metabolism under oxidative stress in Entamoeba histolytica.

    Science.gov (United States)

    Pineda, Erika; Encalada, Rusely; Rodríguez-Zavala, José S; Olivos-García, Alfonso; Moreno-Sánchez, Rafael; Saavedra, Emma

    2010-08-01

    The in vitro Entamoeba histolytica pyruvate:ferredoxin oxidoreductase (EhPFOR) kinetic properties and the effect of oxidative stress on glycolytic pathway enzymes and fluxes in live trophozoites were evaluated. EhPFOR showed a strong preference for pyruvate as substrate over other oxoacids. The enzyme was irreversibly inactivated by a long period of saturating O(2) exposure (IC(50) 0.034 mm), whereas short-term exposure ( 90% inhibition allowed for partial restoration by addition of Fe(2+). CoA and acetyl-CoA prevented, whereas pyruvate exacerbated, inactivation induced by short-term saturating O(2) exposure. Superoxide dismutase was more effective than catalase in preventing the inactivation, indicating that reactive oxygen species (ROS) were involved. Hydrogen peroxide caused inactivation in an Fe(2+)-reversible fashion that was not prevented by the coenzymes, suggesting different mechanisms of enzyme inactivation by ROS. Structural analysis on an EhPFOR 3D model suggested that the protection against ROS provided by coenzymes could be attributable to their proximity to the Fe-S clusters. After O(2) exposure, live parasites displayed decreased enzyme activities only for PFOR (90%) and aldehyde dehydrogenase (ALDH; 68%) of the bifunctional aldehyde-alcohol dehydrogenase (EhADH2), whereas acetyl-CoA synthetase remained unchanged, explaining the increased acetate and lowered ethanol fluxes. Remarkably, PFOR and ALDH activities were restored after return of the parasites to normoxic conditions, which correlated with higher ethanol and lower acetate fluxes. These results identified amebal PFOR and ALDH of EhADH2 activities as markers of oxidative stress, and outlined their relevance as significant controlling steps of energy metabolism in parasites subjected to oxidative stress. PMID:20629749

  15. Remarkable effect of bimetallic nanocluster catalysts for aerobic oxidation of alcohols: combining metals changes the activities and the reaction pathways to aldehydes/carboxylic acids or esters.

    Science.gov (United States)

    Kaizuka, Kosuke; Miyamura, Hiroyuki; Kobayashi, Shū

    2010-11-01

    Selective oxidation of alcohols catalyzed by novel carbon-stabilized polymer-incarcerated bimetallic nanocluster catalysts using molecular oxygen has been developed. The reactivity and the selectivity were strongly dependent on the combination of metals and solvent systems; aldehydes and ketones were obtained by the gold/platinum catalyst in benzotrifluoride, and esters were formed by the gold/palladium catalyst in methanol. To the best of our knowledge, this is the first example that the reaction pathway has been changed dramatically in gold catalysis by combining with a second metal. The differences in the activity and the selectivity are considered to be derived from the difference in the structure of the bimetallic clusters.

  16. Application of ultraviolet, ozone, and advanced oxidation treatments to washwaters to destroy nitrosamines, nitramines, amines, and aldehydes formed during amine-based carbon capture.

    Science.gov (United States)

    Shah, Amisha D; Dai, Ning; Mitch, William A

    2013-03-19

    Although amine-based CO(2) absorption is a leading contender for full-scale postcombustion CO(2) capture at power plants, concerns have been raised about the potential release of carcinogenic N-nitrosamines and N-nitramines formed by reaction of exhaust gas NO(x) with the amines. Experiments with a laboratory-scale pilot unit suggested that washwater units meant to scrub contaminants from absorber unit exhaust could potentially serve as a source of N-nitrosamines via reactions of residual NO(x) with amines accumulating in the washwater. Dosage requirements for the continuous treatment of the washwater recycle line with ultraviolet (UV) light for destruction of N-nitrosamines and N-nitramines, and with ozone or hydroxyl radical-based advanced oxidation processes (AOPs) for destruction of amines and aldehydes, were evaluated. Although capture synergies between UV and ozone treatments.

  17. Quantification of the 2-Deoxyribonolactone and Nucleoside 5 '-Aldehyde Products of 2-Deoxyribose Oxidation in DNA and Cells by Isotope-Dilution Gas Chromatography Mass Spectrometry: Differential Effects of gamma-Radiation and Fe[superscript 2+]-EDTA

    OpenAIRE

    Chan, Wan Simon; Chen, Bingzi; Wang, Lianrong; Taghizadeh, Koli; DeMott, Michael S.; Peter C. Dedon

    2010-01-01

    The oxidation of 2-deoxyribose in DNA has emerged as a critical determinant of the cellular toxicity of oxidative damage to DNA, with oxidation of each carbon producing a unique spectrum of electrophilic products. We have developed and validated an isotope-dilution gas chromatography-coupled mass spectrometry (GC−MS) method for the rigorous quantification of two major 2-deoxyribose oxidation products: the 2-deoxyribonolactone abasic site of 1′-oxidation and the nucleoside 5′-aldehyde of 5′-ox...

  18. Quantification of the 2-deoxyribonolactone and nucleoside 5’-aldehyde products of 2-deoxyribose oxidation in DNA and cells by isotope-dilution gas chromatography mass spectrometry: Differential effects of γ-radiation and Fe2+-EDTA

    OpenAIRE

    Chan, Wan; Chen, Bingzi; Wang, Lianrong; Taghizadeh, Koli; DeMott, Michael S.; Peter C. Dedon

    2010-01-01

    The oxidation of 2-deoxyribose in DNA has emerged as a critical determinant of the cellular toxicity of oxidative damage to DNA, with oxidation of each carbon producing a unique spectrum of electrophilic products. We have developed and validated an isotope-dilution gas chromatography-coupled mass spectrometry (GC-MS) method for the rigorous quantification of two major 2-deoxyribose oxidation products: the 2-deoxyribonolactone abasic site of 1’-oxidation and the nucleoside 5’-aldehyde of 5’-ox...

  19. Kinetic and mechanistic studies on the atmospheric oxidation of oxygenated Volatile Organic Compounds: aldehyde, ketones and esters (solvents or car emissions); Etudes des cinetiques et mecanismes de degradation atmospherique de composes organiques volatils oxygenes: aldehydes, cetones et esters (emissions automobiles et solvants)

    Energy Technology Data Exchange (ETDEWEB)

    Thevenet, R.

    2000-12-01

    The atmospheric fate of oxygenated Volatile Organic Compounds (VOCs), used as solvents or emitted by fuel car combustion, is reported in this thesis. Four saturated aldehydes (propanal, isobutyr-aldehyde, pivalaldehyde and valeraldehyde), two unsaturated aldehydes (acrolein and croton-aldehyde), three ketones (2-butanone, 2-methyl-4-pentanone, 2,4-dimethyl-3-pentanone) and three esters (methyl acrylate, methyl methacrylate and methyl pyruvate) have been studied. The rate coefficients of the OH reactions with the VOCs have been measured over the temperature range 233-372 K, using the Pulsed Laser Photolysis - Laser Induced Fluorescence (PLP-LIF) technique. The photo-reactor have been used to measure the reaction rate constants of these VOCs with Cl or O{sub 3} by the relative method. The obtained results are the first determinations for the most of the VOCs. In a second part, the atmospheric oxidation of the VOCs, initiated by OH, have been studied in smog chambers. Analysis have been performed by IRTF and GC-MS. Photo-reactors have been used, a laboratory photo-reactor in Orleans (160 L) and the European Photo-reactor EUPHORE (200 m{sup 3} with sunlight irradiation). The main oxidation pathways of the VOCs and the main products have been identified. For most of the VOCs, there are the first studies. These experimental results leaded to discuss the atmospheric fate of the VOCs in terms of lifetimes and oxidation products of the VOCs. The tropospheric ozone forming potential of the VOCs and their role in the photo-oxidant pollution have been evaluated. (author)

  20. Synthesis of 5'-Aldehyde Oligonucleotide.

    Science.gov (United States)

    Lartia, Rémy

    2016-01-01

    Synthesis of oligonucleotide ending with an aldehyde functional group at their 5'-end (5'-AON) is possible for both DNA (5'-AODN) and RNA (5'-AORN) series irrespectively of the nature of the last nucleobase. The 5'-alcohol of on-support ODN is mildly oxidized under Moffat conditions. Transient protection of the resulting aldehyde by N,N'-diphenylethylenediamine derivatives allows cleavage, deprotection, and RP-HPLC purification of the protected 5'-AON. Finally, 5'-AON is deprotected by usual acetic acid treatment. In the aggregates, 5'-AON can be now synthesized and purified as routinely as non-modified ODNs, following procedures similar to the well-known "DMT-On" strategy. PMID:26967469

  1. Determination of linear aliphatic aldehydes in heavy metal containing waters by high-performance liquid chromatography using 2,4-dinitrophenylhydrazine derivatization.

    Science.gov (United States)

    Lin, Yi-Liang; Wang, Po-Yen; Hsieh, Ling-Ling; Ku, Kuan-Hsuan; Yeh, Yun-Tai; Wu, Chien-Hou

    2009-09-01

    A simple and sensitive method is described for the determination of picomolar amounts of C(1)-C(9) linear aliphatic aldehydes in waters containing heavy metal ions. In this method, aldehydes were first derivatized with 2,4-dinitrophenylhydrazine (DNPH) at optimized pH 1.8 for 30 min and analyzed by HPLC with UV detector at 365 nm. Factors affecting the derivatization reaction of aldehydes and DNPH were investigated. Cupric ion, an example of heavy metals, is a common oxidative reagent, which may oxidize DNPH and greatly interfere with the determination of aldehydes. EDTA was used to effectively mask the interferences by heavy metal ions. The method detection limits for direct injection of derivatized most aldehydes except formaldehyde were of the order of 7-28 nM. The detection limit can be further lowered by using off-line C(18) adsorption cartridge enrichment. The recoveries of C(1)-C(9) aldehydes were 93-115% with a relative standard deviation of 3.6-8.1% at the 0.1 microM level for aldehydes. The HPLC-DNPH method has been applied for determining aldehyde photoproducts from Cu(II)-amino acid complex systems. PMID:19643424

  2. Fatty Aldehyde and Fatty Alcohol Metabolism: Review and Importance for Epidermal Structure and Function

    OpenAIRE

    Rizzo, William B.

    2013-01-01

    Normal fatty aldehyde and alcohol metabolism is essential for epidermal differentiation and function. Long-chain aldehydes are produced by catabolism of several lipids including fatty alcohols, sphingolipids, ether glycerolipids, isoprenoid alcohols and certain aliphatic lipids that undergo α- or ω-oxidation. The fatty aldehyde generated by these pathways is chiefly metabolized to fatty acid by fatty aldehyde dehydrogenase (FALDH, alternately known as ALDH3A2), which also functions to oxidize...

  3. Effect of variable power levels on the yield of total aerosol mass and formation of aldehydes in e-cigarette aerosols.

    Science.gov (United States)

    Gillman, I G; Kistler, K A; Stewart, E W; Paolantonio, A R

    2016-03-01

    The study objective was to determine the effect of variable power applied to the atomizer of refillable tank based e-cigarette (EC) devices. Five different devices were evaluated, each at four power levels. Aerosol yield results are reported for each set of 25 EC puffs, as mass/puff, and normalized for the power applied to the coil, in mass/watt. The range of aerosol produced on a per puff basis ranged from 1.5 to 28 mg, and, normalized for power applied to the coil, ranged from 0.27 to 1.1 mg/watt. Aerosol samples were also analyzed for the production of formaldehyde, acetaldehyde, and acrolein, as DNPH derivatives, at each power level. When reported on mass basis, three of the devices showed an increase in total aldehyde yield with increasing power applied to the coil, while two of the devices showed the opposite trend. The mass of formaldehyde, acetaldehyde, and acrolein produced per gram of total aerosol produced ranged from 0.01 to 7.3 mg/g, 0.006 to 5.8 mg/g, and aerosols from specific devices, and were compared to estimated exposure from consumption of cigarettes, to occupational and workplace limits, and to previously reported results from other researchers. PMID:26743740

  4. Alcohol Dehydrogenase-1B (rs1229984 and Aldehyde Dehydrogenase-2 (rs671 Genotypes Are Strong Determinants of the Serum Triglyceride and Cholesterol Levels of Japanese Alcoholic Men.

    Directory of Open Access Journals (Sweden)

    Akira Yokoyama

    Full Text Available Elevated serum triglyceride (TG and high-density-lipoprotein cholesterol (HDL-C levels are common in drinkers. The fast-metabolizing alcohol dehydrogenase-1B encoded by the ADH1B*2 allele (vs. ADH1B*1/*1 genotype and inactive aldehyde dehydrogenase-2 encoded by the ALDH2*2 allele (vs. ALDH2*1/*1 genotype modify ethanol metabolism and are prevalent (≈90% and ≈40%, respectively in East Asians. We attempted to evaluate the associations between the ADH1B and ALDH2 genotypes and lipid levels in alcoholics.The population consisted of 1806 Japanese alcoholic men (≥40 years who had undergone ADH1B and ALDH2 genotyping and whose serum TG, total cholesterol, and HDL-C levels in the fasting state had been measured within 3 days after admission.High serum levels of TG (≥150 mg/dl, HDL-C (>80 mg/dl, and low-density-lipoprotein cholesterol (LDL-C calculated by the Friedewald formula ≥140 mg/dl were observed in 24.3%, 16.8%, and 15.6%, respectively, of the subjects. Diabetes, cirrhosis, smoking, and body mass index (BMI affected the serum lipid levels. Multivariate analysis revealed that the presence of the ADH1B*2 allele and the active ALDH2*1/*1 genotype increased the odds ratio (OR; 95% confidence interval for a high TG level (2.22 [1.67-2.94] and 1.39 [0.99-1.96], respectively, and decreased the OR for a high HDL-C level (0.37 [0.28-0.49] and 0.51 [0.37-0.69], respectively. The presence of the ADH1B*2 allele decreased the OR for a high LDL-C level (0.60 [0.45-0.80]. The ADH1B*2 plus ALDH2*1/*1 combination yielded the highest ORs for high TG levels and lowest OR for a high HDL-C level. The genotype effects were more prominent in relation to the higher levels of TG (≥220 mg/dl and HDL-C (≥100 mg/dl.The fast-metabolizing ADH1B and active ALDH2, and especially a combination of the two were strongly associated with higher serum TG levels and lower serum HDL-C levels of alcoholics. The fast-metabolizing ADH1B was associated with lower serum LDL

  5. Sorption Behavior of an Aliphatic Series of Aldehydes in the Presence of Poly(ethylene terephthalate) Blends Containing Aldehyde Scavenging Agents

    OpenAIRE

    Suloff, Eric Charles

    2002-01-01

    The quality of many beverages and food products is compromised by the presence of low molecular weight aldehydes. Aldehydes are commonly formed during storage by the oxidation of lipids or are introduced as migrants from polymeric packaging material. The objective of this project was to evaluate the effectiveness of three aldehyde scavenging agents, blended into poly(ethylene terephthalate) (PET) films, in removing an aliphatic series of aldehydes from an acidified aqueous model solution (p...

  6. Organic acids and aldehydes in rainwater in a northwest region of Spain

    Energy Technology Data Exchange (ETDEWEB)

    Pena, R.M.; Garcia, S.; Herrero, C. [Universidad de Santiago de Compostela, Lugo (Spain). Departamento de Quimica Analitica, Nutricion y Bromatologia

    2002-11-01

    During a 1 year period, measurements of carboxylic acids and aldehydes were carried out in rainwater samples collected at nine different sites in NW Spain surrounding a thermal power plant in order to determine concentration levels and sources. In addition, certain major ions (Cl{sup -}, NO{sub 3}{sup -}, SO{sub 4}{sup 2-}, Na{sup +}, NH{sub 4}{sup +}, K{sup +}, Mg{sup 2+}, Ca{sup 2+}) were also determined. Aldehyde and carboxylic acid concentration patterns and their effects on rainwater composition concerning temporal, seasonal and spatial variations were evaluated. Among carboxylic acids, formic and acetic were predominant (VWA 7.0 and 8.3 {mu}M), while formaldehyde and acroleine were the dominant aldehydes (VWA 0.42 and 1.25 {mu}M). Carboxylic acids were estimated to account for 27.5% of the total free acidity (TFA), whereas sulphuric and nitric acid accounted for 46.2% and 26.2%, respectively. Oxalic acid was demonstrated to be an important contributing compound to the acidification in rainwater representing 7.1% of the TFA. The concentration of aldehydes and carboxylic acids, which originated mainly from biogenic emissions in the area studied, was strongly dependent on the season of the year (growing and non-growing). The ratios of formic to acetic acids are considerably different in the two seasons suggesting that there exist distinct sources in both growing and non-growing seasons. Principal component analysis was applied in order to elucidate the sources of aldehydes and organic acids in rainwater. The prevalence of natural vegetative origins for both of these compounds versus anthropogenic emissions was demonstrated and the importance of the oxidation of aldehydes as a relevant source of organic acids was also established. (author)

  7. Air pollution source apportionment before, during, and after the 2008 Beijing Olympics and association of sources to aldehydes and biomarkers of blood coagulation, pulmonary and systemic inflammation, and oxidative stress in healthy young adults

    Science.gov (United States)

    Altemose, Brent A.

    Based on principal component analysis (PCA) of air pollution data collected during the Summer Olympic Games held in Beijing, China during 2008, the five source types of air pollution identified -- natural soil/road dust, vehicle and industrial combustion, vegetative burning, oil combustion, and secondary formation, were all distinctly lower during the Olympics. This was particularly true for vehicle and industrial combustion and oil combustion, and during the main games period between the opening and closing ceremonies. The reduction in secondary formation was reflective of a reduction in nitrogen oxides, but this also contributed to increased ozone concentrations during the Olympic period. Among three toxic aldehydes measured in Beijing during the same time period, only acetaldehyde had a reduction in mean concentration during the Olympic air pollution control period compared to the pre-Olympic period. Accordingly, acetaldehyde was significantly correlated with primary emission sources including vegetative burning and oil combustion, and with several pollutants emitted mainly from primary sources. In contrast, formaldehyde and acrolein increased during the Olympic air pollution control period; accordingly both were significantly correlated with ozone and with the secondary formation source type. These findings indicate primary sources may dominate for acetaldehyde while secondary sources may dominate for formaldehyde and acrolein. Biomarkers for pulmonary inflammation (exhaled breath condensate (EBC) pH, exhaled nitric oxide, and EBC nitrite) and hemostasis and blood coagulation (vWF and sCD62p) were most consistently associated with vehicle and industrial combustion, oil combustion, and vegetative burning. The systemic inflammation biomarker 8-OHdG was most consistently associated with vehicle and industrial combustion. In contrast, the associations between the biomarkers and the aldehydes were generally not significant or in the hypothesized direction, although

  8. Analysis of endogenous aldehydes in human urine by static headspace gas chromatography-mass spectrometry.

    Science.gov (United States)

    Serrano, María; Gallego, Mercedes; Silva, Manuel

    2016-03-11

    Endogenous aldehydes (EAs) generated during oxidative stress and cell processes are associated with many pathogenic and toxicogenic processes. The aim of this research was to develop a solvent-free and automated analytical method for the determination of EAs in human urine using a static headspace generator sampler coupled with gas chromatography-mass spectrometry (HS-GC-MS). Twelve significant EAs used as markers of different biochemical and physiological processes, namely short- and medium-chain alkanals, α,β-unsaturated aldehydes and dicarbonyl aldehydes have been selected as target analytes. Human urine samples (no dilution is required) were derivatized with O-2,3,4,5,6-pentafluorobenzylhydroxylamine in alkaline medium (hydrogen carbonate-carbonate buffer, pH 10.3). The HS-GC-MS method developed renders an efficient tool for the sensitive and precise determination of EAs in human urine with limits of detection from 1 to 15ng/L and relative standard deviations, (RSDs) from 6.0 to 7.9%. Average recoveries by enriching urine samples ranged between 92 and 95%. Aldehydes were readily determined at 0.005-50μg/L levels in human urine from healthy subjects, smokers and diabetic adults.

  9. Selective Enzymatic Reduction of Aldehydes

    Directory of Open Access Journals (Sweden)

    Patrizia Di Gennaro

    2006-05-01

    Full Text Available Highly selective enzymatic reductions of aldehydes to the corresponding alcohols was performed using an E. coli JM109 whole cell biocatalyst. A selective enzymatic method for the reduction of aldehydes could provide an eco-compatible alternative to chemical methods. The simplicity, fairly wide scope and the very high observed chemoselectivity of this approach are its most unique features.

  10. Aldehyde sources, metabolism, molecular toxicity mechanisms, and possible effects on human health.

    Science.gov (United States)

    O'Brien, Peter J; Siraki, Arno G; Shangari, Nandita

    2005-08-01

    Aldehydes are organic compounds that are widespread in nature. They can be formed endogenously by lipid peroxidation (LPO), carbohydrate or metabolism ascorbate autoxidation, amine oxidases, cytochrome P-450s, or myeloperoxidase-catalyzed metabolic activation. This review compares the reactivity of many aldehydes towards biomolecules particularly macromolecules. Furthermore, it includes not only aldehydes of environmental or occupational concerns but also dietary aldehydes and aldehydes formed endogenously by intermediary metabolism. Drugs that are aldehydes or form reactive aldehyde metabolites that cause side-effect toxicity are also included. The effects of these aldehydes on biological function, their contribution to human diseases, and the role of nucleic acid and protein carbonylation/oxidation in mutagenicity and cytotoxicity mechanisms, respectively, as well as carbonyl signal transduction and gene expression, are reviewed. Aldehyde metabolic activation and detoxication by metabolizing enzymes are also reviewed, as well as the toxicological and anticancer therapeutic effects of metabolizing enzyme inhibitors. The human health risks from clinical and animal research studies are reviewed, including aldehydes as haptens in allergenic hypersensitivity diseases, respiratory allergies, and idiosyncratic drug toxicity; the potential carcinogenic risks of the carbonyl body burden; and the toxic effects of aldehydes in liver disease, embryo toxicity/teratogenicity, diabetes/hypertension, sclerosing peritonitis, cerebral ischemia/neurodegenerative diseases, and other aging-associated diseases.

  11. Effect of commonly used organic solvents on aldehyde oxidase-mediated vanillin, phthalazine and methotrexate oxidation in human, rat and mouse liver subcellular fractions.

    Science.gov (United States)

    Behera, Dayanidhi; Pattem, Rambabu; Gudi, Girish

    2014-08-01

    1. Aldehyde oxidase (AOX) is a cytosolic molybdoflavoprotein enzyme widely distributed across many tissues. In this study, we report the effect of commonly used organic solvents such as dimethyl sulfoxide (DMSO), acetonitrile (ACN), methanol and ethanol on AOX activity in human, rat and mouse liver S9 fractions using vanillin, phthalazine and methotrexate as probe substrates. 2. Methanol was found to be the most potent solvent in inhibiting vanillic acid and 1-phthalazinone formation in comparison to DMSO, ACN and ethanol across the species tested, except 7-hydroxy methotrexate. 3. Treatment with these solvents at approximate IC50 (% v/v) concentrations showed significant reduction in Clint and Vmax of the probe substrates and also resulted in different effects on Km across the species. 4. Marked differences in the activity and affinity towards AOX were observed with different probe substrates with methotrexate showing least activity and affinity as compared to vanillin and phthalazine. 5. Overall, AOX activity seemed to be more resilient to the presence of organic solvents at higher concentrations in human and rodent species. These results suggest that low concentrations of organic solvents are acceptable for in vitro incubations involving AOX-mediated metabolism.

  12. In vitro assessment of human airway toxicity from major aldehydes in automotive emissions

    Energy Technology Data Exchange (ETDEWEB)

    Grafstroem, R.C. [Karolinska Inst., Stockholm (Sweden). Inst. of Environmental Medicine

    1997-09-01

    Automotive exhausts can significantly contribute to the levels of reactive aldehydes, including formaldehyde, acetaldehyde and acrolein, in urban air. The use of alcohols as an alternative fuel for gasoline or diesel may further increase these emissions. Since it is unclear if aldehyde inhalation may induce pathological states, including cancer, in human airways, the toxic properties of the above-mentioned aldehydes were studied in cultured target cell types. Each aldehyde modified vital cellular functions in a dose-dependent manner, and invariably inhibited growth and induced abnormal terminal differentiation. Decreases of cellular thiols and increases of intracellular Ca{sup 2+} were observed, and moreover, variable types and amounts of short-lived or persistent genetic damage were induced. The concentrations required for specified levels of a particular type of injury varied up to 10000-fold among the aldehydes. Overall, distinctive patterns of cytopathological activity were observed, which differed both qualitatively and quantitatively among the aldehydes. Finally, aldehydes inhibited DNA repair processes and increased cytotoxicity and mutagenesis in synergy with other known toxicants, indicating that aldehydes may also enhance damage by other constituents in automotive exhausts. In summary, the aldehydes, notably {sup m}u{sup M}-mM formaldehyde, caused pathological effects and induced mechanisms that relate to acute toxicity and cancer development in airway epithelial cells. Since `no-effect` levels may not exist for carcinogenic agents, the overall results support a need for elimination of aldehydes in automotive exhausts. 41 refs

  13. Fast and Green Microwave-Assisted Conversion of Essential Oil Allylbenzenes into the Corresponding Aldehydes via Alkene Isomerization and Subsequent Potassium Permanganate Promoted Oxidative Alkene Group Cleavage

    DEFF Research Database (Denmark)

    Luu, Thi Xuan Thi; Lam, Trinh To; Le, Thach Ngoc;

    2009-01-01

    oxidation of the latter to the corresponding benzaldehyde by KMnO4/CuSO4 center dot 5H(2)O. The assistance by microwave irradiation results in very short reaction times (vanillin (4-hydroxy-3-methoxybenzaldehyde) has been carried...... out in a similar way, requiring however two additional microwave-assisted synthetic steps for acetylation of the hydroxy group prior to the oxidation reaction, and for the final deacetylation of vanillin acetate (4-acetoxy-3-methoxybenzaldehyde) by KF/Al2O3 under solvent-free conditions, respectively....

  14. Fast and Green Microwave-Assisted Conversion of Essential Oil Allylbenzenes into the Corresponding Aldehydes via Alkene Isomerization and Subsequent Potassium Permanganate Promoted Oxidative Alkene Group Cleavage

    Directory of Open Access Journals (Sweden)

    Thi X. Thi Luu

    2009-09-01

    Full Text Available Essential oil allylbenzenes from have been converted quickly and efficiently into the corresponding benzaldehydes in good yields by a two-step “green” reaction pathway based on a solventless alkene group isomerization by KF/Al2O3 to form the corresponding 1-arylpropene and a subsequent solventless oxidation of the latter to the corresponding benzaldehyde by KMnO4/CuSO4·5H2O. The assistance by microwave irradiation results in very short reaction times (<15 minutes. The green conversion of eugenol (4-allyl-2-methoxyphenol into vanillin (4-hydroxy-3-methoxybenzaldehyde has been carried out in a similar way, requiring however two additional microwave-assisted synthetic steps for acetylation of the hydroxy group prior to the oxidation reaction, and for the final deacetylation of vanillin acetate (4-acetoxy-3-methoxybenzaldehyde by KF/Al2O3 under solvent-free conditions, respectively.

  15. PPRODUCTION OF AROMATIC ALDEHYDE BY MICROWAVE CATALYTIC OXIDATION OF A LIGNIN MODEL COMPOUND WITH La-CONTAINING SBA-15/H2O2 SYSTEMS

    Directory of Open Access Journals (Sweden)

    Xiaoli Gu

    2010-07-01

    Full Text Available A convenient and efficient application of heterogeneous La-containing SBA-15 systems for the microwave assisted oxidation of a lignin model phenolic monomer, 4-hydroxy-1-phenylpropane, is reported. Low-cost and environmentally friendly H2O2 was used as the oxygen atom donor. The catalyst was prepared by immobilizing lanthanum species on the periodic mesoporous channels of siliceous SBA-15. Powder X-ray diffraction data and ICP-AES revealed that the host retains its hexagonal mesoporous structure after immobilization and most of the lanthanum species are better dispersed in the calcined materials. The surface area and pore size of La/SBA-15 was considerably decreased, indicating the intrapore confinement of the Lanthanum species. The activity of the La/SBA-15 was investigated in the oxidation of 4-hydroxy-1-phenylpropane in the presence of hydrogen peroxide as oxidant. 70.5% conversion of 4-hydroxy-1-phenylpropane was obtained after 30 min of reaction under 200W microwave irradiation, compared to a poor 28.1% degradation after 24h under conventional heating. The possibility of recycling the catalyst was studied.

  16. Fast and Green Microwave-Assisted Conversion of Essential Oil Allylbenzenes into the Corresponding Aldehydes via Alkene Isomerization and Subsequent Potassium Permanganate Promoted Oxidative Alkene Group Cleavage

    OpenAIRE

    Thi X. Thi Luu; Trinh To Lam; Thach Ngoc Le; Fritz Duus

    2009-01-01

    Essential oil allylbenzenes from have been converted quickly and efficiently into the corresponding benzaldehydes in good yields by a two-step “green” reaction pathway based on a solventless alkene group isomerization by KF/Al2O3 to form the corresponding 1-arylpropene and a subsequent solventless oxidation of the latter to the corresponding benzaldehyde by KMnO4/CuSO4·5H2O. The assistance by microwave irradiation results in very short reaction times (<15 minutes). The green conversion of ...

  17. The ORF slr0091 of Synechocystis sp. PCC6803 encodes a high-light induced aldehyde dehydrogenase converting apocarotenals and alkanals

    KAUST Repository

    Trautmann, Danika

    2013-07-05

    Oxidative cleavage of carotenoids and peroxidation of lipids lead to apocarotenals and aliphatic aldehydes called alkanals, which react with vitally important compounds, promoting cytotoxicity. Although many enzymes have been reported to deactivate alkanals by converting them into fatty acids, little is known about the mechanisms used to detoxify apocarotenals or the enzymes acting on them. Cyanobacteria and other photosynthetic organisms must cope with both classes of aldehydes. Here we report that the Synechocystis enzyme SynAlh1, encoded by the ORF slr0091, is an aldehyde dehydrogenase that mediates oxidation of both apocarotenals and alkanals into the corresponding acids. Using a crude lysate of SynAlh1-expressing Escherichia coli cells, we show that SynAlh1 converts a wide range of apocarotenals and alkanals, with a preference for apocarotenals with defined chain lengths. As suggested by in vitro incubations and using engineered retinal-forming E. coli cells, we found that retinal is not a substrate for SynAlh1, making involvement in Synechocystis retinoid metabolism unlikely. The transcript level of SynAlh1 is induced by high light and cold treatment, indicating a role in the stress response, and the corresponding gene is a constituent of a stress-related operon. The assumptions regarding the function of SynAlh are further supported by the surprisingly high homology to human and plant aldehyde dehydrogenase that have been assigned to aldehyde detoxification. SynAlh1 is the first aldehyde dehydrogenase that has been shown to form both apocarotenoic and fatty acids. This dual function suggests that its eukaryotic homologs may also be involved in apocarotenal metabolism, a function that has not been considered so far. Aldehyde dehydrogenases play an important role in detoxification of reactive aldehydes. Here, we report on a cyanbacterial enzyme capable in converting two classes of lipid-derived aldehydes, apocaotenals and alkanals. The corresponding gene is a

  18. Carbon-Carbon Bond Formation and Hydrogen Production in the Ketonization of Aldehydes.

    Science.gov (United States)

    Orozco, Lina M; Renz, Michael; Corma, Avelino

    2016-09-01

    Aldehydes possess relatively high chemical energy, which is the driving force for disproportionation reactions such as Cannizzaro and Tishchenko reactions. Generally, this energy is wasted if aldehydes are transformed into carboxylic acids with a sacrificial oxidant. Here, we describe a cascade reaction in which the surplus energy of the transformation is liberated as molecular hydrogen for the oxidation of heptanal to heptanoic acid by water, and the carboxylic acid is transformed into potentially industrially relevant symmetrical ketones by ketonic decarboxylation. The cascade reaction is catalyzed by monoclinic zirconium oxide (m-ZrO2 ). The reaction mechanism has been studied through cross-coupling experiments between different aldehydes and acids, and the final symmetrical ketones are formed by a reaction pathway that involves the previously formed carboxylic acids. Isotopic studies indicate that the carboxylic acid can be formed by a hydride shift from the adsorbed aldehyde on the metal oxide surface in the absence of noble metals. PMID:27539722

  19. Reversible, partial inactivation of plant betaine aldehyde dehydrogenase by betaine aldehyde: mechanism and possible physiological implications.

    Science.gov (United States)

    Zárate-Romero, Andrés; Murillo-Melo, Darío S; Mújica-Jiménez, Carlos; Montiel, Carmina; Muñoz-Clares, Rosario A

    2016-04-01

    In plants, the last step in the biosynthesis of the osmoprotectant glycine betaine (GB) is the NAD(+)-dependent oxidation of betaine aldehyde (BAL) catalysed by some aldehyde dehydrogenase (ALDH) 10 enzymes that exhibit betaine aldehyde dehydrogenase (BADH) activity. Given the irreversibility of the reaction, the short-term regulation of these enzymes is of great physiological relevance to avoid adverse decreases in the NAD(+):NADH ratio. In the present study, we report that the Spinacia oleracea BADH (SoBADH) is reversibly and partially inactivated by BAL in the absence of NAD(+)in a time- and concentration-dependent mode. Crystallographic evidence indicates that the non-essential Cys(450)(SoBADH numbering) forms a thiohemiacetal with BAL, totally blocking the productive binding of the aldehyde. It is of interest that, in contrast to Cys(450), the catalytic cysteine (Cys(291)) did not react with BAL in the absence of NAD(+) The trimethylammonium group of BAL binds in the same position in the inactivating or productive modes. Accordingly, BAL does not inactivate the C(450)SSoBADH mutant and the degree of inactivation of the A(441)I and A(441)C mutants corresponds to their very different abilities to bind the trimethylammonium group. Cys(450)and the neighbouring residues that participate in stabilizing the thiohemiacetal are strictly conserved in plant ALDH10 enzymes with proven or predicted BADH activity, suggesting that inactivation by BAL is their common feature. Under osmotic stress conditions, this novel partial and reversible covalent regulatory mechanism may contribute to preventing NAD(+)exhaustion, while still permitting the synthesis of high amounts of GB and avoiding the accumulation of the toxic BAL.

  20. Optimization of Oxidator Level to Produce Binderless Bamboo Particleboard

    OpenAIRE

    Suhasman; Massijaya, M.Y.; Hadi, Y.S.; Santoso, A

    2010-01-01

    Oxidation treatment of bamboo particle would be considered as one of the alternative methods to produce binderless particleboard. Since most of composite panels including particleboard is manufactured using formaldehyde base adhesive emission from the product is a main concern in contrast to binderless panels which don???t cause such problem. The main objective of this research was to determine the optimal level of hydrogen peroxide and ferrous sulphate as oxidator in particleboard manufa...

  1. The levels of nitric oxide in megaloblastic anemia

    Directory of Open Access Journals (Sweden)

    Emin Kaya

    2009-12-01

    Full Text Available Objective: The purpose of this study was to investigate the relationship between nitric oxide degradation products (nitrate and nitrite levels and megaloblastic anemia which is treated with cyalocobalamin. Materials and Methods: A total of 30 patients with megaloblastic anemia (16 Male, 14 Female were included in the study. Cyanocobalamin was administered (1.000 µg/day intramuscularly until the reticulocyte crisis occurred to the normal range. The control group consisted of 30 healthy subjects (15 Male, 15 Female. Nitric oxide levels were measured before treatment and compared with the values obtained during peak reticulocyte count. Results: Plasma direct nitrite, total nitrite and nitrate levels were 24,86±3,87, 60.56±7,01 and 36,02±5,24 in before treatment versus 15,48±3,05, 38,92±6,44 and 22,77±6,04 μmol/dl in after treatment, respectively. Plasma direct nitrite, total nitrite and nitrate levels were significantly lower in after treatment compared with the before treatment (p<0.001. Conclusion: Nitric oxide levels are seen to increase in megaloblastic anemia. This study suggested that abnormalities in the nitric oxide levels in megaloblastic anemia are restored by vitamin B12 replacement therapy.

  2. Fatty aldehydes in cyanobacteria are a metabolically flexible precursor for a diversity of biofuel products.

    Directory of Open Access Journals (Sweden)

    Brett K Kaiser

    Full Text Available We describe how pathway engineering can be used to convert a single intermediate derived from lipid biosynthesis, fatty aldehydes, into a variety of biofuel precursors including alkanes, free fatty acids and wax esters. In cyanobacteria, long-chain acyl-ACPs can be reduced to fatty aldehydes, and then decarbonylated to alkanes. We discovered a cyanobacteria class-3 aldehyde-dehydrogenase, AldE, that was necessary and sufficient to instead oxidize fatty aldehyde precursors into fatty acids. Overexpression of enzymes in this pathway resulted in production of 50 to 100 fold more fatty acids than alkanes, and the fatty acids were secreted from the cell. Co-expression of acyl-ACP reductase, an alcohol-dehydrogenase and a wax-ester-synthase resulted in a third fate for fatty aldehydes: conversion to wax esters, which accumulated as intracellular lipid bodies. Conversion of acyl-ACP to fatty acids using endogenous cyanobacterial enzymes may allow biofuel production without transgenesis.

  3. Anti-oxidative role of quercetin derived from Allium cepa on aldehyde oxidase (OX-LDL) and hepatocytes apoptosis in streptozotocin-induced diabetic rat

    Institute of Scientific and Technical Information of China (English)

    Mina Bakhshaeshi; Arash Khaki; Fatemeh Fathiazad; Amir Afshin Khaki; Elham Ghadamkheir

    2012-01-01

    Objective:To study the role of Quercetin in streptozotocin-induced diabetes in rats. Methods:Wistar male rat (n=40) were allocated into three groups, control group (n=10) and Quercetin (QR) group received 15 mg/kg (IP) QR, (n=10), and diabetic group that received 55 mg/kg (IP) streptozotocin (STZ) (n=20) which was subdivided to two groups of 10; STZ group and treatment group. Treatment group received 55 mg/kg (IP) STZ plus 15 mg/kg QR, daily for 4 weeks, respectively;however, the control group just received an equal volume of distilled water daily (IP). Diabetes was induced by a single (IP) injection of streptozotocin (55 mg/kg). Animals were kept in standard condition. Twenty-eight days after inducing diabetic, 5 mL blood were collected for TAC, MDA and Ox-LDL levels and liver tissues of rat in whole groups were removed then prepared for apoptosis analysis by Tunel method. Results:Apoptotic cells significantly decreased in group that has received 15 mg/kg (IP) Quercetin (P<0.05) in comparison to experimental groups (P<0.05). Conclusions:Since in our study 15 mg/kg (IP) Quercetin have significantly Preventive effect on liver cells damages by reducing number of apoptotic cells in Liver, so it seems that using it can be effective for treatment in diabetic rat.

  4. Fatty Aldehyde and Fatty Alcohol Metabolism: Review and Importance for Epidermal Structure and Function

    Science.gov (United States)

    Rizzo, William B.

    2014-01-01

    Normal fatty aldehyde and alcohol metabolism is essential for epidermal differentiation and function. Long-chain aldehydes are produced by catabolism of several lipids including fatty alcohols, sphingolipids, ether glycerolipids, isoprenoid alcohols and certain aliphatic lipids that undergo α- or ω-oxidation. The fatty aldehyde generated by these pathways is chiefly metabolized to fatty acid by fatty aldehyde dehydrogenase (FALDH, alternately known as ALDH3A2), which also functions to oxidize fatty alcohols as a component of the fatty alcohol:NAD oxidoreductase (FAO) enzyme complex. Genetic deficiency of FALDH/FAO in patients with Sjögren-Larsson syndrome (SLS) results in accumulation of fatty aldehydes, fatty alcohols and related lipids (ether glycerolipids, wax esters) in cultured keratinocytes. These biochemical changes are associated with abnormalities in formation of lamellar bodies in the stratum granulosum and impaired delivery of their precursor membranes to the stratum corneum (SC). The defective extracellular SC membranes are responsible for a leaky epidermal water barrier and ichthyosis. Although lamellar bodies appear to be the pathogenic target for abnormal fatty aldehyde/alcohol metabolism in SLS, the precise biochemical mechanisms are yet to be elucidated. Nevertheless, studies in SLS highlight the critical importance of FALDH and normal fatty aldehyde/alcohol metabolism for epidermal function. PMID:24036493

  5. Kinetics of forming aldehydes in frying oils and their distribution in French fries revealed by LC-MS-based chemometrics

    Science.gov (United States)

    Aldehydes are major secondary lipid oxidation products (LOPs) from heating vegetable oils and deep frying. The routes and reactions that generate aldehydes have been extensively investigated, but the sequences and kinetics of their formation in oils are poorly defined. In this study, a platform comb...

  6. Oxidized low density lipoprotein increases RANKL level in human vascular cells. Involvement of oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Mazière, Cécile, E-mail: maziere.cecile@chu-amiens.fr [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France); Salle, Valéry [Internal Medicine, North Hospital University, Place Victor Pauchet, Amiens 80000 (France); INSERM U1088 (EA 4292), SFR CAP-Santé (FED 4231), University of Picardie – Jules Verne (France); Gomila, Cathy; Mazière, Jean-Claude [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France)

    2013-10-18

    Highlights: •Oxidized LDL enhances RANKL level in human smooth muscle cells. •The effect of OxLDL is mediated by the transcription factor NFAT. •UVA, H{sub 2}O{sub 2} and buthionine sulfoximine also increase RANKL level. •All these effects are observed in human fibroblasts and endothelial cells. -- Abstract: Receptor Activator of NFκB Ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) have been shown to play a role not only in bone remodeling but also in inflammation, arterial calcification and atherosclerotic plaque rupture. In human smooth muscle cells, Cu{sup 2+}-oxidized LDL (CuLDL) 10–50 μg/ml increased reactive oxygen species (ROS) and RANKL level in a dose-dependent manner, whereas OPG level was not affected. The lipid extract of CuLDL reproduced the effects of the whole particle. Vivit, an inhibitor of the transcription factor NFAT, reduced the CuLDL-induced increase in RANKL, whereas PKA and NFκB inhibitors were ineffective. LDL oxidized by myeloperoxidase (MPO-LDL), or other pro-oxidant conditions such as ultraviolet A (UVA) irradiation, incubation with H{sub 2}O{sub 2} or with buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis{sub ,} also induced an oxidative stress and enhanced RANKL level. The increase in RANKL in pro-oxidant conditions was also observed in fibroblasts and endothelial cells. Since RANKL is involved in myocardial inflammation, vascular calcification and plaque rupture, this study highlights a new mechanism whereby OxLDL might, by generation of an oxidative stress, exert a deleterious effect on different cell types of the arterial wall.

  7. INTERACTION OF ALDEHYDES DERIVED FROM LIPID PEROXIDATION AND MEMBRANE PROTEINS.

    Directory of Open Access Journals (Sweden)

    Stefania ePizzimenti

    2013-09-01

    Full Text Available A great variety of compounds are formed during lipid peroxidation of polyunsaturated fatty acids of membrane phospholipids. Among them, bioactive aldehydes, such as 4-hydroxyalkenals, malondialdehyde (MDA and acrolein, have received particular attention since they have been considered as toxic messengers that can propagate and amplify oxidative injury. In the 4-hydroxyalkenal class, 4-hydroxy-2-nonenal (HNE is the most intensively studied aldehyde, in relation not only to its toxic function, but also to its physiological role. Indeed, HNE can be found at low concentrations in human tissues and plasma and participates in the control of biological processes, such as signal transduction, cell proliferation and differentiation. Moreover, at low doses, HNE exerts an anti-cancer effect, by inhibiting cell proliferation, angiogenesis, cell adhesion and by inducing differentiation and/or apoptosis in various tumor cell lines. It is very likely that a substantial fraction of the effects observed in cellular responses, induced by HNE and related aldehydes, be mediated by their interaction with proteins, resulting in the formation of covalent adducts or in the modulation of their expression and/or activity. In this review we focus on membrane proteins affected by lipid peroxidation-derived aldehydes, under physiological and pathological conditions.

  8. Oxidative Stress in Autism: Elevated Cerebellar 3-nitrotyrosine Levels

    Directory of Open Access Journals (Sweden)

    Elizabeth M. Sajdel-Sulkowska

    2008-01-01

    Full Text Available It has been suggested that oxidative stress and/or mercury compounds play an important role in the pathophysiology of autism. This study compared for the first time the cerebellar levels of the oxidative stress marker 3-nitrotyrosine (3-NT, mercury (Hg and the antioxidant selenium (Se levels between control and autistic subjects. Tissue homogenates were prepared in the presence of protease inhibitors from the frozen cerebellar tissue of control (n=10; mean age, 15.5 years; mean PMI, 15.5 hours and autistic (n=9; mean age 12.1 years; mean PMI, 19.3 hours subjects. The concentration of cerebellar 3-NT, determined by ELISA, in controls ranged from 13.69 to 49.04 pmol g-1 of tissue; the concentration of 3-NT in autistic cases ranged from 3.91 to 333.03 pmol g-1 of tissue. Mean cerebellar 3-NT was elevated in autism by 68.9% and the increase was statistically significant (p=0.045. Cerebellar Hg, measured by atomic absorption spectrometry ranged from 0.9 to 35 pmol g-1 tissue in controls (n=10 and from 3.2 to 80.7 pmol g-1 tissue in autistic cases (n=9; the 68.2% increase in cerebellar Hg was not statistically significant. However, there was a positive correlation between cerebellar 3-NT and Hg levels (r=0.7961, p=0.0001. A small decrease in cerebellar Se levels in autism, measured by atomic absorption spectroscopy, was not statistically significant but was accompanied by a 42.9% reduction in the molar ratio of Se to Hg in the autistic cerebellum. While preliminary, the results of the present study add elevated oxidative stress markers in brain to the growing body of data reflecting greater oxidative stress in autism.

  9. Increased platelet oxidative metabolism, blood oxidative stress and neopterin levels after ultra-endurance exercise.

    Science.gov (United States)

    de Lucas, Ricardo Dantas; Caputo, Fabrizio; Mendes de Souza, Kristopher; Sigwalt, André Roberto; Ghisoni, Karina; Lock Silveira, Paulo Cesar; Remor, Aline Pertile; da Luz Scheffer, Débora; Guglielmo, Luiz Guilherme Antonacci; Latini, Alexandra

    2014-01-01

    The purpose of the present investigation was to identify muscle damage, inflammatory response and oxidative stress blood markers in athletes undertaking the ultra-endurance MultiSport Brazil race. Eleven well-trained male athletes (34.3 ± 3.1 years, 74.0 ± 7.6 kg; 172.2 ± 5.1 cm) participated in the study and performed the race, which consisted of about 90 km of alternating off-road running, mountain biking and kayaking. Twelve hours before and up to 15 minutes after the race a 10 mL blood sample was drawn in order to measure the following parameters: lactate dehydrogenase and creatine kinase activities, lipid peroxidation, catalase activity, protein carbonylation, respiratory chain complexes I, II and IV activities, oxygen consumption and neopterin concentrations. After the race, plasma lactate dehydrogenase and creatine kinase activities were significantly increased. Erythrocyte TBA-RS levels and plasma protein carbonylation were markedly augmented in post-race samples. Additionally, mitochondrial complex II activity and oxygen consumption in post-race platelet-rich plasma were also increased. These altered biochemical parameters were accompanied by increased plasma neopterin levels. The ultra-endurance event provoked systemic inflammation (increased neopterin) accompanied by marked oxidative stress, likely by increasing oxidative metabolism (increased oxidative mitochondrial function). This might be advantageous during prolonged exercise, mainly for efficient substrate oxidation at the mitochondrial level, even when tissue damage is induced.

  10. Microsphere coated substrate containing reactive aldehyde groups

    Science.gov (United States)

    Rembaum, Alan (Inventor); Yen, Richard C. K. (Inventor)

    1984-01-01

    A synthetic organic resin is coated with a continuous layer of contiguous, tangential, individual microspheres having a uniform diameter preferably between 100 Angstroms and 2000 Angstroms. The microspheres are an addition polymerized polymer of an unsaturated aldehyde containing 4 to 20 carbon atoms and are covalently bonded to the substrate by means of high energy radiation grafting. The microspheres contain reactive aldehyde groups and can form conjugates with proteins such as enzymes or other aldehyde reactive materials.

  11. Thermal degradation behavior of hypochlorite-oxidized starch nanocrystals under different oxidized levels.

    Science.gov (United States)

    Wei, Benxi; Li, Hongyan; Tian, Yaoqi; Xu, Xueming; Jin, Zhengyu

    2015-06-25

    The thermal degradation behavior of hypochlorite-oxidized starch nanocrystals (OSNCs) was evaluated in this study. Carbonyl and carboxyl groups in OSNCs increased from 0.006 and 0.091mmol/g to 0.033 and 0.129mmol/g, respectively, as the active chlorine concentration increased from 1% to 4% (w/w). Compared with starch nanocrystals (SNCs), the initial degradation temperature of OSNCs with 4% oxidization decreased from 273°C to 253°C. Two degradation processes were detected using differential thermal analysis. The activation energy of the low-temperature process increased with increasing oxidization level because of removal of sulfate esters and reduction of the decomposition products of H2O during oxidation. With increasing temperature, the H2O generating from decarboxylation and decomposition of the carboxyl groups may catalyze SNCs depolymerization, leading to decrease in the activation energy of the high-temperature process. OSNCs (4% oxidized level) can be used in dry process below 253°C to avoid degradation.

  12. Levels of oxidative damage and lipid peroxidation in thyroid neoplasia.

    LENUS (Irish Health Repository)

    Young, Orla

    2012-02-01

    BACKGROUND: This study assessed the presence of oxidative damage and lipid peroxidation in thyroid neoplasia. METHODS: Using tissue microarrays and immunohistochemistry, we assessed levels of DNA damage (8-oxo-dG) and lipid peroxidation (4-HNE) in 71 follicular thyroid adenoma (FTA), 45 papillary thyroid carcinoma (PTC), and 17 follicular thyroid carcinoma (FTC) and matched normal thyroid tissue. RESULTS: Cytoplasmic 8-oxo-dG and 4-HNE expression was significantly higher in FTA, FTC, and PTC tissue compared to matched normal tissue (all p values < .001). Similarly, elevated nuclear levels of 8-oxo-dG were seen in all in FTA, FTC, and PTC tissue compared to matched normal (p values < .07, < .001, < .001, respectively). In contrast, a higher level of 4-HNE expression was detected in normal thyroid tissue compared with matched tumor tissue (p < .001 for all groups). Comparing all 3 groups, 4-HNE levels were higher than 8-oxo-dG levels (p < .001 for all groups) except that cytoplasmic levels of 8-oxo-dG were higher than 4-HNE in all (p < .001). These results were independent of proliferation status. CONCLUSION: High levels of DNA damage and lipid peroxidation in benign and malignant thyroid neoplasia indicates this damage is an early event that may influence disease progression.

  13. Study on physico-chemical properties of dialdehyde yam starch with different aldehyde group contents

    International Nuclear Information System (INIS)

    Dialdehyde yam starches (DASs) are prepared and characterized. Compared with native starch, viscosity average molecular weight of DASs decreases, and the extent of degradation depends on content of the aldehyde groups. Fourier transform infrared (FT-IR) spectra confirm that the characteristic peak for C=O group at 1732 cm-1 is enhanced with the increasing of content of the aldehyde groups. Scanning electron microscopy (SEM) micrographs show that the surface of starch granules becomes wrinkled. X-ray diffraction (XRD) patterns clearly indicate that their crystallinity decreases with the increasing content of the aldehyde groups before they become amorphous at higher oxidation states. The experimental results of thermogravimetric analysis (TGA) show that DASs have poor stability as compared to native starch. With the increase in content of the aldehyde groups, the thermal stability of DAS declines gradually. According to the results of differential scanning calorimetry (DSC), gelatinization temperature (To and Tp) of DASs are increased, whereas the gelatinization enthalpy decreased.

  14. The atomic level journey from aqueous polyoxometalate to metal oxide

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Yu; Fast, Dylan B.; Ruther, Rose E.; Amador, Jenn M.; Fullmer, Lauren B.; Decker, Shawn R.; Zakharov, Lev N.; Dolgos, Michelle R., E-mail: Michelle.Dolgos@oregonstate.edu; Nyman, May, E-mail: May.Nyman@oregonstate.edu

    2015-01-15

    Aqueous precursors tailored for the deposition of thin film materials are desirable for sustainable, simple, low energy production of advanced materials. Yet the simple practice of using aqueous precursors is complicated by the multitude of interactions that occur between ions and water during dehydration. Here we use lithium polyoxoniobate salts to investigate the fundamental interactions in the transition from precursor cluster to oxide film. Small-angle X-ray scattering of solutions, total X-ray scattering of intermediate gels, and morphological and structural characterization of the lithium niobate thin films reveal the atomic level transitions between these states. The studies show that (1) lithium–[H{sub 2}Nb{sub 6}O{sub 19}]{sup 6−} has drastically different solution behaviour than lithium–[Nb{sub 6}O{sub 19}]{sup 8−}, linked to the precursor salt structure (2) in both compositions, the intermediate gel preserves the polyoxoniobate clusters and show similar local order and (3) the morphology and phases of deposited films reflect the ions behaviour throughout the journey from cluster solution to metal oxide. - Graphical abstract: Aqueous lithium polyoxoniobate salts were used to prepare lithium niobate (LiNbO{sub 3}) thin films. Fundamental studies were performed to investigate the interactions in the transition from precursor cluster to the oxide film. It was found that acid–base and ion-association chemistries of the aqueous and gel systems significantly affect the key processes in this atom-level journey. - Highlights: • Lithium polyoxoniobate clusters were synthesized with control over Li:Nb ratio as precursors for LiNbO{sub 3} films. • X-ray scattering studies in solution and the solid-state revealed differences controlled by Li:Nb ratio. • Film deposition studies revealed phase, composition and morphology is controlled by Li:Nb ratio. • Cluster to film transformation was revealed using total X-ray scattering and TGA.

  15. The use of tomato aminoaldehyde dehydrogenase 1 for the detection of aldehydes in fruit distillates.

    Science.gov (United States)

    Frömmel, Jan; Tarkowski, Petr; Kopečný, David; Šebela, Marek

    2016-09-25

    Plant NAD(+)-dependent aminoaldehyde dehydrogenases (AMADHs, EC 1.2.1.19) belong to the family 10 of aldehyde dehydrogenases. They participate in the metabolism of polyamines or osmoprotectants. The enzymes are characterized by their broad substrate specificity covering ω-aminoaldehydes, aliphatic and aromatic aldehydes as well as nitrogen-containing heterocyclic aldehydes. The isoenzyme 1 from tomato (Solanum lycopersicum; SlAMADH1) oxidizes aliphatic aldehydes very efficiently and converts also furfural, its derivatives or benzaldehyde, which are present at low concentrations in alcoholic distillates such as fruit brandy. In this work, SlAMADH1 was examined as a bioanalytical tool for their detection. These aldehydes arise from fermentation processes or thermal degradation of sugars and their presence is related to health complications after consumption including nausea, emesis, sweating, decrease in blood pressure, hangover headache, among others. Sixteen samples of slivovitz (plum brandy) from local producers in Moravia, Czech Republic, were analyzed for their aldehyde content using a spectrophotometric activity assay with SlAMADH1. In all cases, there were oxidative responses observed when monitoring NADH production in the enzymatic reaction. Aldehydes in the distillate samples were also subjected to a standard determination using reversed-phase HPLC with spectrophotometric and tandem mass spectrometric detection after a derivatization with 2,4-dinitrophenylhydrazine. Results obtained by both methods were found to correlate well for a majority of the analyzed samples. The possible applicability of SlAMADH1 for the evaluation of aldehyde content in food and beverages has now been demonstrated. PMID:26703808

  16. Identification and characterisation of Aedes aegypti aldehyde dehydrogenases involved in pyrethroid metabolism.

    Directory of Open Access Journals (Sweden)

    Nongkran Lumjuan

    Full Text Available Pyrethroid insecticides, especially permethrin and deltamethrin, have been used extensively worldwide for mosquito control. However, insecticide resistance can spread through a population very rapidly under strong selection pressure from insecticide use. The upregulation of aldehyde dehydrogenase (ALDH has been reported upon pyrethroid treatment. In Aedes aegypti, the increase in ALDH activity against the hydrolytic product of pyrethroid has been observed in DDT/permethrin-resistant strains. The objective of this study was to identify the role of individual ALDHs involved in pyrethroid metabolism.Three ALDHs were identified; two of these, ALDH9948 and ALDH14080, were upregulated in terms of both mRNA and protein levels in a DDT/pyrethroid-resistant strain of Ae. aegypti. Recombinant ALDH9948 and ALDH14080 exhibited oxidase activities to catalyse the oxidation of a permethrin intermediate, phenoxybenzyl aldehyde (PBald, to phenoxybenzoic acid (PBacid.ALDHs have been identified in association with permethrin resistance in Ae. aegypti. Characterisation of recombinant ALDHs confirmed the role of this protein in pyrethroid metabolism. Understanding the biochemical and molecular mechanisms of pyrethroid resistance provides information for improving vector control strategies.

  17. Combined atmospheric oxidant capacity and increased levels of exhaled nitric oxide

    Science.gov (United States)

    Yang, Changyuan; Li, Huichu; Chen, Renjie; Xu, Wenxi; Wang, Cuicui; Tse, Lap Ah; Zhao, Zhuohui; Kan, Haidong

    2016-07-01

    Nitrogen dioxide and ozone are two interrelated oxidative pollutants in the atmosphere. Few studies have evaluated the health effects of combined oxidant capacity (O x ). We investigated the short-term effects of O x on fractional exhaled nitric oxide (FeNO), a well-established biomarker for airway inflammation, in a group of chronic obstructive pulmonary disease patients. Real-time concentrations of O x were obtained by calculating directly the sum of nitrogen dioxide and ozone. Linear mixed-effect models were applied to explore the acute effects of O x on FeNO levels. Short-term exposure to Ox was significantly associated with elevated FeNO. This effect was strongest in the first 24 h after exposure, and was robust to the adjustment of PM2.5. A 10 μg m‑3 increase in 24 h average concentrations of O x was associated with 4.28% (95% confidence interval: 1.19%, 7.37%) increase in FeNO. The effect estimates were statistically significant only among males, elders, and those with body mass index ≥24 kg m‑2, a comorbidity, higher educational attainment, or moderate airflow limitation. This analysis demonstrated an independent effect of O x on respiratory inflammation, and suggested that a single metric O x might serve as a preferable indicator of atmospheric oxidative capacity in further air pollution epidemiological studies.

  18. The role of nitric oxide in low level light therapy

    Science.gov (United States)

    Hamblin, Michael R.

    2008-02-01

    The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing tissue damage by reducing cellular apoptosis has been known for almost forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial. Firstly the biochemical mechanisms underlying the positive effects are incompletely understood, and secondly the complexity of choosing amongst a large number of illumination parameters has led to the publication of a number of negative studies as well as many positive ones. This review will focus on the role of nitric oxide in the cellular and tissue effects of LLLT. Red and near-IR light is primarily absorbed by cytochrome c oxidase (unit four in the mitochondrial respiratory chain). Nitric oxide produced in the mitochondria can inhibit respiration by binding to cytochrome c oxidase and competitively displacing oxygen, especially in stressed or hypoxic cells. If light absorption displaced the nitric oxide and thus allowed the cytochrome c oxidase to recover and cellular respiration to resume, this would explain many of the observations made in LLLT. Why the effect is only seen in hypoxic, stressed or damaged cells or tissues? How the effects can keep working for some time (hours or days) postillumination? Why increased NO concentrations are sometimes measured in cell culture or in animals? How blood flow can be increased? Why angiogenesis is sometimes increased after LLLT in vivo?

  19. Cellular level loading and heating of superparamagnetic iron oxide nanoparticles.

    Science.gov (United States)

    Kalambur, Venkat S; Longmire, Ellen K; Bischof, John C

    2007-11-20

    Superparamagnetic iron oxide nanoparticles (NPs) hold promise for a variety of biomedical applications due to their properties of visualization using magnetic resonance imaging (MRI), heating with radio frequency (rf), and movement in an external magnetic field. In this study, the cellular loading (uptake) mechanism of dextran- and surfactant-coated iron oxide NPs by malignant prostate tumor cells (LNCaP-Pro5) has been studied, and the feasibility of traditional rf treatment and a new laser heating method was evaluated. The kinetics of cell loading was quantified using magnetophoresis and a colorimetric assay. The results showed that loading of surfactant-coated iron oxide NPs with LNCaP-Pro5 was saturable with time (at 24 h) and extracellular concentration (11 pg Fe/cell at 0.5 mg Fe/mL), indicating that the particles are taken up by an "adsorptive endocytosis" pathway. Dextran-coated NPs, however, were taken up less efficiently (1 pg Fe/cell at 0.5 mg Fe/mL). Loading did not saturate with concentration suggesting uptake by fluid-phase endocytosis. Magnetophoresis suggests that NP-loaded cells can be held using external magnetic fields in microcirculatory flow velocities in vivo or in an appropriately designed extracorporeal circuit. Loaded cells were heated using traditional rf (260A, 357 kHz) and a new laser method (532 nm, 7 ns pulse duration, 0.03 J/pulse, 20 pulse/s). Iron oxide in water was found to absorb sufficiently strongly at 532 nm such that heating of individual NPs and thus loaded cells (1 pg Fe/cell) was effective (10 pg Fe/cell) and longer duration (30 min) when compared to laser to accomplish cell destruction (50% viability at 10 pg Fe/cell). Scaling calculations show that the pulsed laser method can lead to single-cell (loaded with NPs) treatments (200 degrees C temperature change at the surface of an individual NP) unlike traditional rf heating methods which can be used only for bulk tissue level treatments. In a mixture of normal and NP

  20. Electro-oxidation of methanol and formic acid on platinum nanoparticles with different oxidation levels

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Chien-Te, E-mail: cthsieh@saturn.yzu.edu.tw [Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan 320, Taiwan (China); Hsiao, Han-Tsung; Tzou, Dong-Ying; Yu, Po-Yuan [Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan 320, Taiwan (China); Chen, Po-Yen; Jang, Bi-Sheng [Materials and Electro-Optics Research Division, National Chung-Shan Institute of Science and Technology, Taoyuan 325, Taiwan (China)

    2015-01-15

    Herein reported is an atomic layer deposition (ALD) process of platinum (Pt) from (methylcyclopentadienyl) trimethylplatinum (MeCpPtMe{sub 3}) and oxygen (O{sub 2}) for synthesizing the Pt electrocatalysts toward methanol and formic acid oxidation. The as-synthesized Pt catalysts are thermally reduced in 5 vol% H{sub 2} within temperature window of 150–450 °C. The reduction treatment induces a decrease in amount of Pt oxide (Pt–O) species, e.g., PtO and PtO{sub 2}. The presence of Pt–O species not only enhances catalytic activity but also improves anti-poisoning ability toward the oxidation of methanol and formic acid. The improved activity originates from the fact that the Pt–O species, formed by the ALD route, creates a large number of active sites (e.g., Pt–O{sub ads} and Pt–(OH){sub ads}) to strip the CO-adsorbed sites, leading to a high-level of CO tolerance. This work also proposes a stepwise reaction steps to shed some lights on how the Pt–O species promote the catalytic activity. - Highlights: • This study adopts atomic layer deposition (ALD) to grow metallic Pt nanoparticles. • The Pt catalysts show catalytic activity toward methanol and formic acid oxidation. • The reduction treatment induces a decrease in amount of Pt oxide (Pt–O) species. • The Pt–O species creates a number of active sites to strip the CO-adsorbed sites. • A stepwise reaction step concerning the promoted catalytic activity is proposed.

  1. Role of the Molybdoflavoenzyme Aldehyde Oxidase Homolog 2 in the Biosynthesis of Retinoic Acid: Generation and Characterization of a Knockout Mouse▿ †

    Science.gov (United States)

    Terao, Mineko; Kurosaki, Mami; Barzago, Maria Monica; Fratelli, Maddalena; Bagnati, Renzo; Bastone, Antonio; Giudice, Chiara; Scanziani, Eugenio; Mancuso, Alessandra; Tiveron, Cecilia; Garattini, Enrico

    2009-01-01

    The mouse aldehyde oxidase AOH2 (aldehyde oxidase homolog 2) is a molybdoflavoenzyme. Harderian glands are the richest source of AOH2, although the protein is detectable also in sebaceous glands, epidermis, and other keratinized epithelia. The levels of AOH2 in the Harderian gland and skin are controlled by genetic background, being maximal in CD1 and C57BL/6 and minimal in DBA/2, CBA, and 129/Sv strains. Testosterone is a negative regulator of AOH2 in Harderian glands. Purified AOH2 oxidizes retinaldehyde into retinoic acid, while it is devoid of pyridoxal-oxidizing activity. Aoh2−/− mice, the first aldehyde oxidase knockout animals ever generated, are viable and fertile. The data obtained for this knockout model indicate a significant role of AOH2 in the local synthesis and biodisposition of endogenous retinoids in the Harderian gland and skin. The Harderian gland's transcriptome of knockout mice demonstrates overall downregulation of direct retinoid-dependent genes as well as perturbations in pathways controlling lipid homeostasis and cellular secretion, particularly in sexually immature animals. The skin of knockout mice is characterized by thickening of the epidermis in basal conditions and after UV light exposure. This has correlates in the corresponding transcriptome, which shows enrichment and overall upregulation of genes involved in hypertrophic responses. PMID:18981221

  2. Increased hepatic fatty acids uptake and oxidation by LRPPRC-driven oxidative phosphorylation reduces blood lipid levels

    Directory of Open Access Journals (Sweden)

    Ping Zhou

    2016-07-01

    Full Text Available Hyperlipidemia is one of the major risk factors of atherosclerosis and other cardiovascular diseases. This study aimed to investigate the impact of leucine rich pentatricopeptide repeat containing protein (LRPPRC-driven hepatic oxidative phoshorylation on blood lipid levels. The hepatic LRPPRC level was modulated by liver-specific transgenic or adeno-associated virus 8 carried shRNA targeting Lrpprc (aav-shLrpprc. Mice were fed with a high fat diet to induce obesity. Gene expression was analyzed by quantitative real-time PCR and / or western blot. The hepatic ATP level, hepatic and serum lipids contents, and mitochondria oxidative phosphorylation complex activities were measured using specific assay kits. The uptake and oxidation of fatty acid by hepatocytes were assessed using 14C-palmitate. LRPPRC regulated the expression of genes encoded by mitochondrial genome but not those by nuclear genome involved in mitochondria biogenesis, oxidative phosphorylation, and lipid metabolism. Increased oxidative phosphorylation in liver mediated by LRPPRC resulted in the increase of hepatic ATP level. Lrpprc promoted palmitate uptake and oxidation by hypatocytes. The hepatic and serum triglyceride and total cholesterol levels were inversely associated with the hepatic LRPPRC level. These data demonstrated that LRPPRC-driven hepatic oxidative phosphorylation could promote fatty acids uptake and oxidation by hepatocytes and reduce both hepatic and circulating triglyceride and cholesterol levels.

  3. Cough and exhaled nitric oxide levels: what happens with exercise?

    Science.gov (United States)

    Petsky, Helen L; Kynaston, Jennifer Anne; McElrea, Margaret; Turner, Catherine; Isles, Alan; Chang, Anne B

    2013-01-01

    Cough associated with exertion is often used as a surrogate marker of asthma. However, to date there are no studies that have objectively measured cough in association with exercise in children. Our primary aim was to examine whether children with a pre-existing cough have an increase in cough frequency during and post-exercise. We hypothesized that children with any coughing illness will have an increase in cough frequency post-exercise regardless of the presence of exercise-induced broncho-constriction (EIB) or atopy. In addition, we hypothesized that Fractional exhaled nitric oxide (FeNO) levels decreases post-exercise regardless of the presence of EIB or atopy. Children with chronic cough and a control group without cough undertook an exercise challenge, FeNO measurements and a skin prick test, and wore a 24-h voice recorder to objectively measure cough frequency. The association between recorded cough frequency, exercise, atopy, and presence of EIB was tested. We also determined if the change in FeNO post exercise related to atopy or EIB. Of the 50 children recruited (35 with cough, 15 control), 7 had EIB. Children with cough had a significant increase in cough counts (median 7.0, inter-quartile ranges, 0.5, 24.5) compared to controls (2.0, IQR 0, 5.0, p = 0.028) post-exercise. Presence of atopy or EIB did not influence cough frequency. FeNO level was significantly lower post-exercise in both groups but the change was not influenced by atopy or EIB. Cough post-exertion is likely a generic response in children with a current cough. FeNO level decreases post-exercise irrespective of the presence of atopy or EIB. A larger study is necessary confirm or refute our findings.

  4. The longitudinal effect of the aldehyde dehydrogenase 2*2 allele on the risk for nonalcoholic fatty liver disease

    Science.gov (United States)

    Oniki, K; Morita, K; Watanabe, T; Kajiwara, A; Otake, K; Nakagawa, K; Sasaki, Y; Ogata, Y; Saruwatari, J

    2016-01-01

    Aldehyde dehydrogenase 2 (ALDH2) detoxifies toxic aldehydes and has a key role in protecting the liver. An elevated gamma-glutamyl transferase (GGT) level is related to oxidative stress and nonalcoholic fatty liver disease (NAFLD). We herein investigated the association between inactive ALDH2*2 allele (rs671) and the risk of NAFLD, including the relationship to the GGT level. A retrospective follow-up study (mean 5.4±1.1 years) was conducted among 341 Japanese health screening program participants. The receiver operating characteristic curve indicated that the GGT level predicted the development of NAFLD (area under the curve: 0.65, P<0.05) with a cutoff value of 25.5 IUl−1. The longitudinal risk of NAFLD was higher in the ALDH2*2 allele carriers than in the noncarriers (odds ratio (OR): 2.30, 95% confidence interval (CI): 1.21–4.40), and the risk was further increased among the *2 allele carriers with GGT values ⩾25.5 IUl−1 (OR: 4.28, 95% CI: 1.80–10.19). On the other hand, there were no significant changes in the subjects' body weight and body mass index during observation period. The ALDH2*2 allele, in relation to the GGT level, may potentially be a novel risk factor for NAFLD. PMID:27214654

  5. Isolation of liver aldehyde oxidase containing fractions from different animals and determination of kinetic parameters for benzaldehyde

    Directory of Open Access Journals (Sweden)

    Kadam R

    2008-01-01

    Full Text Available Aldehyde oxidase activity containing fractions from rabbit, guinea pig, rat and mouse livers were obtained by heat treatment and ammonium sulfate precipitation. Aldehyde oxidase activity was observed in rabbit and guinea pig livers, while aldehyde oxidase activity was absent in rat and mouse liver fractions. Enzyme kinetic parameters, K m and V max , were determined for the oxidation of benzaldehyde to benzoic acid by rabbit and guinea pig liver fractions, by spectrophotometric method, with potassium ferricyanide as the electron acceptor. The K m values obtained for both animal liver fractions were in the range of 10.3-19.1 µM.

  6. Macro Level Modeling of a Tubular Solid Oxide Fuel Cell

    Directory of Open Access Journals (Sweden)

    Farshid Zabihian

    2010-11-01

    Full Text Available This paper presents a macro-level model of a solid oxide fuel cell (SOFC stack implemented in Aspen Plus® for the simulation of SOFC system. The model is 0-dimensional and accepts hydrocarbon fuels such as reformed natural gas, with user inputs of current density, fuel and air composition, flow rates, temperature, pressure, and fuel utilization factor. The model outputs the composition of the exhaust, work produced, heat available for the fuel reformer, and electrochemical properties of SOFC for model validation. It was developed considering the activation, concentration, and ohmic losses to be the main over-potentials within the SOFC, and mathematical expressions for these were chosen based on available studies in the literature. The model also considered the water shift reaction of CO and the methane reforming reaction. The model results were validated using experimental data from Siemens Westinghouse. The results showed that the model could capture the operating pressure and temperature dependency of the SOFC performance successfully in an operating range of 1–15 atm for pressure and 900 °C–1,000 °C for temperature. Furthermore, a sensitivity analysis was performed to identify the model constants and input parameters that impacted the over-potentials.

  7. Aldehyde oxidase activity in fresh human skin.

    Science.gov (United States)

    Manevski, Nenad; Balavenkatraman, Kamal Kumar; Bertschi, Barbara; Swart, Piet; Walles, Markus; Camenisch, Gian; Schiller, Hilmar; Kretz, Olivier; Ling, Barbara; Wettstein, Reto; Schaefer, Dirk J; Pognan, Francois; Wolf, Armin; Litherland, Karine

    2014-12-01

    Human aldehyde oxidase (AO) is a molybdoflavoenzyme that commonly oxidizes azaheterocycles in therapeutic drugs. Although high metabolic clearance by AO resulted in several drug failures, existing in vitro-in vivo correlations are often poor and the extrahepatic role of AO practically unknown. This study investigated enzymatic activity of AO in fresh human skin, the largest organ of the body, frequently exposed to therapeutic drugs and xenobiotics. Fresh, full-thickness human skin was obtained from 13 individual donors and assayed with two specific AO substrates: carbazeran and zoniporide. Human skin explants from all donors metabolized carbazeran to 4-hydroxycarbazeran and zoniporide to 2-oxo-zoniporide. Average rates of carbazeran and zoniporide hydroxylations were 1.301 and 0.164 pmol⋅mg skin(-1)⋅h(-1), resulting in 13 and 2% substrate turnover, respectively, after 24 hours of incubation with 10 μM substrate. Hydroxylation activities for the two substrates were significantly correlated (r(2) = 0.769), with interindividual variability ranging from 3-fold (zoniporide) to 6-fold (carbazeran). Inclusion of hydralazine, an irreversible inhibitor of AO, resulted in concentration-dependent decrease of hydroxylation activities, exceeding 90% inhibition of carbazeran 4-hydroxylation at 100 μM inhibitor. Reaction rates were linear up to 4 hours and well described by Michaelis-Menten enzyme kinetics. Comparison of carbazeran and zoniporide hydroxylation with rates of triclosan glucuronidation and sulfation and p-toluidine N-acetylation showed that cutaneous AO activity is comparable to tested phase II metabolic reactions, indicating a significant role of AO in cutaneous drug metabolism. To our best knowledge, this is the first report of AO enzymatic activity in human skin. PMID:25249692

  8. Dependence of riverine nitrous oxide emissions on dissolved oxygen levels

    Science.gov (United States)

    Rosamond, Madeline S.; Thuss, Simon J.; Schiff, Sherry L.

    2012-10-01

    Nitrous oxide is a potent greenhouse gas, and it destroys stratospheric ozone. Seventeen per cent of agricultural nitrous oxide emissions come from the production of nitrous oxide in streams, rivers and estuaries, in turn a result of inorganic nitrogen input through leaching, runoff and sewage. The Intergovernmental Panel on Climate Change and global nitrous oxide budgets assume that riverine nitrous oxide emissions increase linearly with dissolved inorganic nitrogen loads, but data are sparse and conflicting. Here we report measurements over two years of nitrous oxide emissions in the Grand River, Canada, a seventh-order temperate river that is affected by agricultural runoff and outflow from a waste-water treatment plant. Emissions were disproportionately high in urban areas and during nocturnal summer periods. Moreover, annual emission estimates that are based on dissolved inorganic nitrogen loads overestimated the measured emissions in a wet year and underestimated them in a dry year. We found no correlations of nitrous oxide emissions with nitrate or dissolved inorganic nitrogen, but detected negative correlations with dissolved oxygen, suggesting that nitrate concentrations did not limit emissions. We conclude that future increases in nitrate export to rivers will not necessarily lead to higher nitrous oxide emissions, but more widespread hypoxia most likely will.

  9. Significance of Lipid-Derived Reactive Aldehyde-Specific Immune Complexes in Systemic Lupus Erythematosus

    Science.gov (United States)

    Wang, Gangduo; Pierangeli, Silvia S.; Willis, Rohan; Gonzalez, Emilio B.; Petri, Michelle; Khan, M. Firoze

    2016-01-01

    Even though systemic lupus erythematosus (SLE) is associated with high morbidity and mortality rates among young and middle-aged women, the molecular mechanisms of disease pathogenesis are not fully understood. Previous studies from our laboratory suggested an association between oxidative stress and SLE disease activity (SLEDAI). To further assess the role of reactive oxygen species (ROS) in SLE, we examined the contribution of lipid-derived reactive aldehydes (LDRAs)-specific immune complexes in SLE. Sera from 60 SLE patients with varying SLEDAI and 32 age- and gender- matched healthy controls were analyzed for oxidative stress and related markers. Patients were divided into two groups based on their SLEDAI scores (<6 and ≥ 6). Both SLEDAI groups showed higher serum 4-hydroxynonenal (HNE)-/malondialdehyde (MDA)-protein adducts and their specific immune complexes (HNE-/MDA-specific ICs) together with IL-17 than the controls, but the levels were significantly greater in the high SLEDAI (≥ 6) group. Moreover, the serum levels of anti-oxidant enzymes Cu/Zn superoxide dismutase (SOD) and catalase (CAT) were significantly reduced in both patient groups compared to controls. Remarkably, for the first time, our data show that increased HNE-/MDA-specific ICs are positively associated with SLEDAI and elevated circulating immune complexes (CICs), suggesting a possible causal relationship among oxidative stress, LDRA-specific ICs and the development of SLE. Our findings, apart from providing firm support to an association between oxidative stress and SLE, also suggest that these oxidative stress markers, especially the HNE-/MDA-specific ICs, may be useful in evaluating the prognosis of SLE as well as in elucidating the mechanisms of disease pathogenesis. PMID:27749917

  10. PHYSICAL AND MECHANICAL PROPERTIES OF BINDERLESS PARTICLEBOARD MADE FROM CANDLENUT WOOD IN VARIOUS OXIDATOR LEVELS

    OpenAIRE

    Suhasman; Saad, Sahriyanti

    2011-01-01

    The purpose of this study was to determine optimal oxidator level in manufacture of binderless particleboard (BP) using oxidation treatment. The raw material used was candlenut wood particles (Aleurites moluccana) which pass 10 mesh in size. The air dried particles were oxidized with four levels of hydrogen peroxide, namely 5%, 10%, 15%, and 20% (based on particle dry-weight), and two levels of ferrous sulphate namely 5% and 7.5% (based on ferrous sulphate weight). The board which manufactur...

  11. [Fatty aldehydes of the plasmalogenic form of phosphatidylethanolamine in the vertebrate brain].

    Science.gov (United States)

    Kruglova, E E

    1979-01-01

    Studies have been made on the composition of fatty aldehydes of plasmalogen form of ethanolamine phospholipid in the brain of 28 fish species (13 cartilaginous and 15 teleost species, exhibiting different level of organization of the nervous system, marine and freshwater, dwelling in different habitats), as well as in the brain of other vertebrates. It was found that in all primitive species of cartilaginous fish high degree of unsaturation of fatty aldehydes is observed; in higher species the degree of unsaturation is much lower. The highest degree of unsaturation of fatty aldehydes was demonstrated for abyssal species of cartilaginous and teleost fishes. In warm-water species which dwell in the upper layers, unlike all other fishes investigated, almost all fatty aldehydes are saturated. The ratio of unsaturated and saturated fatty aldehydes in fish brain depends on the entity of phylogenetic and ecological factors. Studies on other vertebrates show that in warm-blooded animals saturated fatty aldehydes predominate, whereas in cold-blooded-unsaturated ones are more abundant. PMID:314210

  12. Catalytic production of methyl acrylates by gold-mediated cross coupling of unsaturated aldehydes with methanol

    Science.gov (United States)

    Karakalos, Stavros; Zugic, Branko; Stowers, Kara J.; Biener, Monika M.; Biener, Juergen; Friend, Cynthia M.; Madix, Robert J.

    2016-10-01

    Modern methods of esterification, one of the most important reactions in organic synthesis, are reaching their limits, as far as waste and expense are concerned. Novel chemical approaches to ester formation are therefore of importance. Here we report a simple procedure free of caustic reagents or byproducts for the facile direct oxidative methyl esterification of aldehydes over nanoporous Au catalysts. Complementary model studies on single crystal gold surfaces establish the fundamental reactions involved. We find that methanol more readily reacts with adsorbed active oxygen than do the aldehydes, but that once the aldehydes do react, they form strongly-bound acrylates that block reactive sites and decrease the yields of acrylic esters under steady flow conditions at 420 K. Significant improvements in yield can be achieved by operating at higher temperatures, which render the site-blocking acrylates unstable.

  13. Transcriptional Regulation of Expression of the Maize Aldehyde Dehydrogenase 7 Gene (ZmALDH7B6) in Response to Abiotic Stresses

    Institute of Scientific and Technical Information of China (English)

    GU Ri-liang

    2014-01-01

    Aldehyde dehydrogenases (ALDHs) represent a large protein family, which includes several members that catalyze the oxidation of an aldehyde to its corresponding carboxylic acid in plants. Genes encoding members of theALDH7 subfamily have been suggested to play important roles in various stress adaptations in plants. In this study, quantitative RT-PCR analysis revealed that a maizeALDH7 subfamily member (ZmALDH7B6) was constitutively expressed in various organs, including roots, leaves, immature ears, tassels, and developing seeds. The abundance ofZmALDH7B6 mRNA transcripts in maize roots was increased by ammonium, NaCl, and mannitol treatments. To further analyze tissue-speciifc and stress-induced expression patterns, the 1.5-kb 5´-lfankingZmALDH7B6 promoter region was fused to the β-glucuronidase (GUS) reporter gene and introduced into maize plants. In roots of independent transgenic lines, there was signiifcant induction of GUS activity in response to ammonium supply, conifrming ammonium-dependent expression ofZmALDH7B6 at the transcript level. Histochemical staining showed that GUS activity driven by theZmALDH7B6 promoter was mainly localized in the vascular tissues of maize roots. These results suggested thatZmALDH7B6 is induced by multiple environmental stresses in maize roots, and may play a role in detoxifying aldehydes, particularly in vascular tissue.

  14. Nitrite promotes protein carbonylation and Strecker aldehyde formation in experimental fermented sausages: are both events connected?

    Science.gov (United States)

    Villaverde, A; Ventanas, J; Estévez, M

    2014-12-01

    The role played by curing agents (nitrite, ascorbate) on protein oxidation and Strecker aldehyde formation is studied. To fulfill this objective, increasing concentrations of nitrite (0, 75 and 150ppm) and ascorbate (0, 250 and 500ppm) were added to sausages subjected to a 54day drying process. The concurrence of intense proteolysis, protein carbonylation and formation of Strecker aldehydes during processing of sausages suggests that α-aminoadipic semialdehyde (AAS) and γ-glutamic semialdehyde (GGS) may be implicated in the formation of Strecker aldehydes. The fact that nitrite (150ppm, ingoing amount) significantly promoted the formation of protein carbonyls at early stages of processing and the subsequent formation of Strecker aldehydes provides strength to this hypothesis. Ascorbate (125 and 250ppm) controlled the overall extent of protein carbonylation in sausages without declining the formation of Strecker aldehydes. These results may contribute to understanding the chemistry fundamentals of the positive influence of nitrite on the flavor and overall acceptability of cured muscle foods.

  15. Surviving environmental stress: the role of betaine aldehyde dehydrogenase in marine crustaceans

    Directory of Open Access Journals (Sweden)

    NA Stephens-Camacho

    2015-02-01

    Full Text Available Betaine aldehyde dehydrogenase (BADH belongs to the aldehyde dehydrogenases (ALDH family, an ancestral group of enzymes responsible for aldehyde detoxification in several organisms. The BADH enzyme catalyzes the irreversible oxidation of betaine aldehyde to glycine betaine (GB an important osmoptrotector and osmoregulator accumulated in response to cellular osmotic stress. The BADH enzymes have been extensively described in terrestrial organisms, but information in marine crustaceans remains scarce. Research on crustacean stress-adaptive capacity to environmental stressors relates GB accumulation in response to salinity variations. Although GB de novo synthesis is confirmed on crustaceans, its metabolic pathways and regulation mechanism are unexplored. In this work, the state of the knowledge of betaine aldehyde dehydrogenase enzymes in marine crustaceans is summarized, as a mechanism to overcome the deleterious effects of changes in temperature, salinity and dissolved oxygen concentration in seawater. The purpose of this review is to provide a more comprehensive overview to set the basis for exploring novel functions and properties of BADHs on the response of crustaceans to environmental stress.

  16. Alcohol and Aldehyde Dehydrogenases: Retinoid Metabolic Effects in Mouse Knockout Models

    OpenAIRE

    Kumar, Sandeep; Sandell, Lisa L.; Trainor, Paul A; Koentgen, Frank; Duester, Gregg

    2011-01-01

    Retinoic acid (RA) is the active metabolite of vitamin A (retinol) that controls growth and development. The first step of RA synthesis is controlled by enzymes of the alcohol dehydrogenase (ADH) and retinol dehydrogenase (RDH) families that catalyze oxidation of retinol to retinaldehyde. The second step of RA synthesis is controlled by members of the aldehyde dehydrogenase (ALDH) family also known as retinaldehyde dehydrogenase (RALDH) that further oxidize retinaldehyde to produce RA. RA fun...

  17. [Level of nitric oxide in the kidneys during apoptosis activation].

    Science.gov (United States)

    Komarievtseva, I O; Orlova, O A; Blahodarenko, Ie A

    2002-01-01

    The content of nitric oxide stable metabolites in a tissue of kidneys of rats in conditions of activation of apoptosis was investigated. Research was carried out in two models: acute renal failure and a hypertrophy of a unique kidney after a unilateral nephrectomy. Detection of apoptosis was carried out by definition of DNA fragmentation. Substantial increase of the nitric oxide stable metabolites contents is revealed at activation of apoptosis in both models. Change of a ratio of the contents of nitrite--anions in relation to the general contents of NO2- + NO3- is revealed, indicating the role of peroxide processes in effect of nitric oxide and its metabolites on the cell. PMID:14964872

  18. Synthesis of Discodermolide Subunits by S(E)2' Addition of Nonracemic Allenylstannanes to Aldehydes.

    Science.gov (United States)

    Marshall, James A.; Lu, Zhi-Hui; Johns, Brian A.

    1998-02-01

    Three subunits, 15, 29, and 34, of the immunosuppressant discodermolide were prepared starting from (S)-3-[(tert-butyldimethylsilyl)oxy]-2-methylpropanal ((S)-1) and the enantioenriched allenylstannanes (P)-2a, (P)-2b, and (P)-31. The route to 15 involved BF(3)-promoted addition of stannane (P)-2a to aldehyde (S)-1 which afforded the syn,syn-homopropargylic alcohol adduct 3 in 97% yield. The derived p-methoxybenzylidene acetal 5 was treated with Red-Al to effect cleavage of the pivalate and reduction of the double bond leading to the (E)-allylic alcohol 6. Sharpless epoxidation and subsequent addition of Me(2)CuCNLi(2) yielded the syn,syn,syn,anti stereopentad, diol 8. Protection of the secondary alcohol and oxidation of the primary gave aldehyde 12, which was treated with the alpha-bromo allylsilane 13 and CrCl(2), followed by NaH to effect elimination to the diene 15. A similar sequence was employed to prepare aldehyde 29. In this case aldehyde (S)-1 was converted to the anti,syn-homopropargylic alcohol 20 by treatment with the allenyl indium reagent formed in situ from allenylstannane (P)-2b and InBr(3). Epoxy alcohol 24, prepared from alcohol 20 by the above-described sequence, was reduced with Red-Al to afford diol 25. Protection of the secondary alcohol and oxidation of the primary completed the synthesis of 29. The anti,syn-homopropargylic alcohol 32 was obtained through addition of the allenic indium reagent, from allenylstannane (P)-31, to aldehyde (S)-1. Protection of the derived diol 33 as the p-methoxybenzylidene acetal afforded the third subunit, acetylene 34. Addition of the lithio derivative of 34 to aldehyde 29 gave alcohol 35 with the carbinyl stereochemistry needed for C7 of discodermolide as the major product.

  19. Increased Hepatic Fatty Acids Uptake and Oxidation by LRPPRC-Driven Oxidative Phosphorylation Reduces Blood Lipid Levels.

    Science.gov (United States)

    Lei, Shi; Sun, Run-Zhu; Wang, Di; Gong, Mei-Zhen; Su, Xiang-Ping; Yi, Fei; Peng, Zheng-Wu

    2016-01-01

    Hyperlipidemia is one of the major risk factors of atherosclerosis and other cardiovascular diseases. This study aimed to investigate the impact of leucine rich pentatricopeptide repeat containing protein (LRPPRC)-driven hepatic oxidative phoshorylation on blood lipid levels. The hepatic LRPPRC level was modulated by liver-specific transgenic or adeno-associated virus 8 carried shRNA targeting Lrpprc (aav-shLrpprc). Mice were fed with a high fat diet to induce obesity. Gene expression was analyzed by quantitative real-time PCR and / or western blot. The hepatic ATP level, hepatic and serum lipids contents, and mitochondria oxidative phosphorylation (OxPhos) complex activities were measured using specific assay kits. The uptake and oxidation of fatty acid by hepatocytes were assessed using (14)C-palmitate. LRPPRC regulated the expression of genes encoded by mitochondrial genome but not those by nuclear genome involved in mitochondria biogenesis, OxPhos, and lipid metabolism. Increased OxPhos in liver mediated by LRPPRC resulted in the increase of hepatic ATP level. Lrpprc promoted palmitate uptake and oxidation by hypatocytes. The hepatic and serum triglyceride and total cholesterol levels were inversely associated with the hepatic LRPPRC level. These data demonstrated that LRPPRC-driven hepatic OxPhos could promote fatty acids uptake and oxidation by hepatocytes and reduce both hepatic and circulating triglyceride and cholesterol levels. PMID:27462273

  20. Control of lipid oxidation at the mitochondrial level

    DEFF Research Database (Denmark)

    Sahlin, Kent

    2009-01-01

    matrix, beta-oxidation, the tricarboxylic acid cycle, and the electron transport chain (ETC). CHO catabolism may impair lipid oxidation by interfering with the transfer of LCFAs into mitochondria and by competing for mutual cofactors (i.e., nicotinamide adenine dinucleotide and (or) coenzyme A (Co......A)). The different effect of energy state on the catabolism of CHO and lipids is likely to be of major importance in explaining the shift in fuel utilization during intensive exercise. Formation of acetyl-CoA from CHO is activated by a low energy state, and will lead to accumulation of products that are inhibitory...

  1. Tropospheric chemistry of natural hydrocarbons, aldehydes, and peroxy radicals: Their connections to sulfuric acid production and climate effects

    International Nuclear Information System (INIS)

    Recent work has shown that natural hydrocarbon emissions can significantly affect the levels of urban and regional tropospheric ozone. We report on the reactivities of these biogenic trace gases, particularly isoprene, focusing on their importance in the production of aldehydes and peroxy radicals, leading to increased levels of hydrogen over regional forests. Hydrogen peroxide can lead to the wet oxidation of sulfur dioxide to acidic sulfate in aerosols, fogs, and clouds. In turn, acidic sulfate can act to as a light scattering aerosol and a source of cloud condensation nuclei (CCN), potentially leading to global cooling. Aerosol sulfate and other dissolved organic and inorganic compounds can also play important roles as a greenhouse species in the lower troposphere

  2. Sjögren-Larsson syndrome. Deficient activity of the fatty aldehyde dehydrogenase component of fatty alcohol:NAD+ oxidoreductase in cultured fibroblasts.

    OpenAIRE

    Rizzo, W B; Craft, D A

    1991-01-01

    Sjögren-Larsson syndrome (SLS) is an inherited disorder associated with impaired fatty alcohol oxidation due to deficient activity of fatty alcohol:NAD+ oxidoreductase (FAO). FAO is a complex enzyme which consists of two separate proteins that sequentially catalyze the oxidation of fatty alcohol to fatty aldehyde and fatty acid. To determine which enzymatic component of FAO was deficient in SLS, we assayed fatty aldehyde dehydrogenase (FALDH) and fatty alcohol dehydrogenase in cultured fibrob...

  3. Lipid Peroxidation, Antioxidant Enzymes and Levels of Nitric Oxide in Sheep Infected with Fasciola hepatica

    OpenAIRE

    BENZER, Fulya; OZAN, Sema TEMİZER

    2003-01-01

    In this study, the levels of malondialdehyde and activities of catalase and glutathione peroxidase, two antioxidant enzymes, and the levels of nitric oxide in sheep infected with Fasciola hepatica were measured. The level of malondialdehyde in plasma and tissue was measured according to the Yagi and Ohkawa methods, respectively. The activities of catalase and glutathione peroxidase were measured according to the methods of Aebi and Beutler, respectively. The level of nitric oxide was deter...

  4. Development of a microfluidic paper-based analytical device for the determination of salivary aldehydes.

    Science.gov (United States)

    Ramdzan, Adlin N; Almeida, M Inês G S; McCullough, Michael J; Kolev, Spas D

    2016-05-01

    A low cost, disposable and easy to use microfluidic paper-based analytical device (μPAD) was developed for simple and non-invasive determination of total aldehydes in saliva with a potential to be used in epidemiological studies to assess oral cancer risk. The μPAD is based on the colour reaction between aldehydes (e.g. acetaldehyde, formaldehyde), 3-methyl-2-benzothiazolinone hydrazone (MBTH) and iron(III) to form an intense blue coloured formazan dye. The newly developed μPAD has a 3D design with two overlapping paper layers. The first layer comprises 15 circular detection zones (8 mm in diameter), each impregnated with 8 μL of MBTH, while the second layer contains 15 reagent zones (4 mm in diameter). Two μL of iron(III) chloride are added to each one of the second layer zones after the addition of sample to the detection zones in the first layer. All hydrophilic zones of the μPAD are defined by wax printing using a commercial wax printer. Due to the 2-step nature of the analytical reaction, the two paper layers are separated by a cellulose acetate interleaving sheet to allow for the reaction between the aldehydes in the saliva sample with MBTH to proceed first with the formation of an azine, followed by a blue coloured reaction between the azine and the oxidized by iron(III) form of MBTH, produced after the removal of the interleaving sheet. After obtaining a high resolution image of the detection side zone of the device using a flatbed scanner, the intensity of the blue colour within each detection zone is measured with Image J software. Under optimal conditions, the μPAD is characterised by a working range of 20.4-114.0 μM, limit of detection of 6.1 μM, and repeatability, expressed as RSD, of less than 12.7% (n = 5). There is no statistically significant difference at the 95% confidence level between the results obtained by the μPAD and the reference method (Student's t-test: 0.090 < 0.38). The optimized μPAD is stable for more than 41 days

  5. Aldehyde Dehydrogenase Gene Superfamily in Populus: Organization and Expression Divergence between Paralogous Gene Pairs.

    Directory of Open Access Journals (Sweden)

    Feng-Xia Tian

    Full Text Available Aldehyde dehydrogenases (ALDHs constitute a superfamily of NAD(P+-dependent enzymes that catalyze the irreversible oxidation of a wide range of reactive aldehydes to their corresponding nontoxic carboxylic acids. ALDHs have been studied in many organisms from bacteria to mammals; however, no systematic analyses incorporating genome organization, gene structure, expression profiles, and cis-acting elements have been conducted in the model tree species Populus trichocarpa thus far. In this study, a comprehensive analysis of the Populus ALDH gene superfamily was performed. A total of 26 Populus ALDH genes were found to be distributed across 12 chromosomes. Genomic organization analysis indicated that purifying selection may have played a pivotal role in the retention and maintenance of PtALDH gene families. The exon-intron organizations of PtALDHs were highly conserved within the same family, suggesting that the members of the same family also may have conserved functionalities. Microarray data and qRT-PCR analysis indicated that most PtALDHs had distinct tissue-specific expression patterns. The specificity of cis-acting elements in the promoter regions of the PtALDHs and the divergence of expression patterns between nine paralogous PtALDH gene pairs suggested that gene duplications may have freed the duplicate genes from the functional constraints. The expression levels of some ALDHs were up- or down-regulated by various abiotic stresses, implying that the products of these genes may be involved in the adaptation of Populus to abiotic stresses. Overall, the data obtained from our investigation contribute to a better understanding of the complexity of the Populus ALDH gene superfamily and provide insights into the function and evolution of ALDH gene families in vascular plants.

  6. Radon and aldehyde concentrations in the indoor environment. Final report

    International Nuclear Information System (INIS)

    Findings regarding indoor air contaminants in the energy-efficient residence (EER) in Mt. Airy, Maryland are reported. The objectives of the study were to collect and analyze relevant air quality samples (specifically radon and aldehydes), characterize the indoor air quality with respect to radon and aldehydes, and develop relationships between air infiltration rates and contaminant levels. One-fifth of the measured formaldehyde concentrations were in the range that may cause health concerns. Although indoor temperature and relative humidity affect indoor HCHO concentration, the elevated formaldehyde concentrations were measured under very low air infiltration rates. The data show that ventilation of the indoor air space is somewhat effective in reducing high HCHO concentrations. The operation of the heat exchanger led to an increase of the air infiltration rate which in turn resulted in substantial reduction of formaldehyde concentrations. A considerable number of the collected samples of indoor air displayed radon concentrations at levels higher than 1.0 to 4.0 nCim-3 (assuming an equilibrium factor of 0.5, these radon levels would correspond to working levels above the health guidelines suggested by the US EPA for homes in Florida built on land reclaimed from phosphate mining). As in the case of indoor formaldehyde concentrations, elevated indoor concentrations are substantially reduced when the infiltration rate is increased. The data base shows that the use of the air to air heat exchanger leads to reduction of indoor radon concentration by increasing the residential ventilation rate

  7. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for...

  8. Acrolein—an α,β-Unsaturated Aldehyde: A Review of Oral Cavity Exposure and Oral Pathology Effects

    Science.gov (United States)

    Aizenbud, Dror; Aizenbud, Itay; Reznick, Abraham Z.; Avezov, Katia

    2016-01-01

    Acrolein is a highly reactive unsaturated aldehyde widely present in the environment, particularly as a product of tobacco smoke. Our previous studies indicated the adverse consequences of even short-term acrolein exposure and proposed a molecular mechanism of its potential harmful effect on oral cavity keratinocytic cells. In this paper we chose to review the broad spectrum of acrolein sources such as pollution, food, and smoking. Consequently, in this paper we consider a high level of oral exposure to acrolein through these sources and discuss the noxious effects it has on the oral cavity including on salivary quality and contents, oral resistance to oxidative stress, and stress mechanism activation in a variety of oral cells. PMID:27487309

  9. Acrolein—an α,ß-Unsaturated Aldehyde: A Review of Oral Cavity Exposure and Oral Pathology Effects

    Directory of Open Access Journals (Sweden)

    Dror Aizenbud

    2016-07-01

    Full Text Available Acrolein is a highly reactive unsaturated aldehyde widely present in the environment, particularly as a product of tobacco smoke. Our previous studies indicated the adverse consequences of even short-term acrolein exposure and proposed a molecular mechanism of its potential harmful effect on oral cavity keratinocytic cells. In this paper we chose to review the broad spectrum of acrolein sources such as pollution, food, and smoking. Consequently, in this paper we consider a high level of oral exposure to acrolein through these sources and discuss the noxious effects it has on the oral cavity including on salivary quality and contents, oral resistance to oxidative stress, and stress mechanism activation in a variety of oral cells.

  10. Theoretical structural study on the adsorption properties of aliphatic aldehydes on ZnO nanoclusters and graphene-like nanosheets systems

    Science.gov (United States)

    Tayebee, R.; Zamand, N.; Hosseini-nasr, A.; Kargar Razi, M.

    2014-05-01

    The structure optimizations for some aliphatic aldehydes adsorbed on ZnO nanoclusters, and graphene-like nanosheets were carried out using the B3LYP/LanL2DZ calculations and the adsorption energies were calculated. It was considered that adsorption of the examined aldehydes on the ZnO nanoclusters and graphene-like nanosheets occurred through carbonyl oxygens of aldehyde molecules with the surface Zn2+ ions of the central ring. Aldehydes with the general formula of R-COH (R denotes a branched or linear aliphatic chain with maximum of three carbon atoms) were considered. Also, Effects of chain length were investigated on the orientation of the aldehyde molecules with respect to the nanosheet and nanocluster surfaces. Findings revealed that the adsorption energy was decreased with enhancing chain length. However, the most negative adsorption energy was obtained for iso-butyraldehyde, as a branched aldehyde. Interaction of the aldehyde molecules with the surfaces of nanosheets were analyzed by means of DOS analysis and Bader's method. We hope the obtained results be helpful in identifying the mechanism of cyclotrimerization of aliphatic aldehydes on the surface of zinc oxide nanoparticles.

  11. Kinetics of Forming Aldehydes in Frying Oils and Their Distribution in French Fries Revealed by LC-MS-Based Chemometrics.

    Science.gov (United States)

    Wang, Lei; Csallany, A Saari; Kerr, Brian J; Shurson, Gerald C; Chen, Chi

    2016-05-18

    In this study, the kinetics of aldehyde formation in heated frying oils was characterized by 2-hydrazinoquinoline derivatization, liquid chromatography-mass spectrometry (LC-MS) analysis, principal component analysis (PCA), and hierarchical cluster analysis (HCA). The aldehydes contributing to time-dependent separation of heated soybean oil (HSO) in a PCA model were grouped by the HCA into three clusters (A1, A2, and B) on the basis of their kinetics and fatty acid precursors. The increases of 4-hydroxynonenal (4-HNE) and the A2-to-B ratio in HSO were well-correlated with the duration of thermal stress. Chemometric and quantitative analysis of three frying oils (soybean, corn, and canola oils) and French fry extracts further supported the associations between aldehyde profiles and fatty acid precursors and also revealed that the concentrations of pentanal, hexanal, acrolein, and the A2-to-B ratio in French fry extracts were more comparable to their values in the frying oils than other unsaturated aldehydes. All of these results suggest the roles of specific aldehydes or aldehyde clusters as novel markers of the lipid oxidation status for frying oils or fried foods.

  12. Kinetics of Forming Aldehydes in Frying Oils and Their Distribution in French Fries Revealed by LC-MS-Based Chemometrics.

    Science.gov (United States)

    Wang, Lei; Csallany, A Saari; Kerr, Brian J; Shurson, Gerald C; Chen, Chi

    2016-05-18

    In this study, the kinetics of aldehyde formation in heated frying oils was characterized by 2-hydrazinoquinoline derivatization, liquid chromatography-mass spectrometry (LC-MS) analysis, principal component analysis (PCA), and hierarchical cluster analysis (HCA). The aldehydes contributing to time-dependent separation of heated soybean oil (HSO) in a PCA model were grouped by the HCA into three clusters (A1, A2, and B) on the basis of their kinetics and fatty acid precursors. The increases of 4-hydroxynonenal (4-HNE) and the A2-to-B ratio in HSO were well-correlated with the duration of thermal stress. Chemometric and quantitative analysis of three frying oils (soybean, corn, and canola oils) and French fry extracts further supported the associations between aldehyde profiles and fatty acid precursors and also revealed that the concentrations of pentanal, hexanal, acrolein, and the A2-to-B ratio in French fry extracts were more comparable to their values in the frying oils than other unsaturated aldehydes. All of these results suggest the roles of specific aldehydes or aldehyde clusters as novel markers of the lipid oxidation status for frying oils or fried foods. PMID:27128101

  13. Patients with systemic vasculitis have increased levels of autoantibodies against oxidized LDL

    NARCIS (Netherlands)

    Swets, BP; Brouwer, DAJ; Tervaert, JWC

    2001-01-01

    Oxidation of low density lipoprotein (LDL) is considered to play an important role in the development of atherosclerosis and increased levels of autoantibodies against oxidized LDL have been found in patients with various manifestations of atherosclerosis. Patients with vasculitis are prone to the d

  14. Allylation of Aromatic Aldehyde under Microwave Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZHANG,Yu-Mei; JIA,Xue-Feng; WANG,Jin-Xian

    2004-01-01

    @@ Allylation of carbonyl compounds is one of the most interesting processes for the preparation of homoallylic alcohols. Over the past few decades, many reagents have been developed for such reactions[1~3]. In this paper, we first report allylic zinc reagent 1, which can be prepared from zinc dust and allyl bromide conveniently in THF, and reacted with aromatic aldehyde to give homo-allylic alcohols under microwave irradiation.

  15. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    Directory of Open Access Journals (Sweden)

    P. O. Wennberg

    2010-04-01

    Full Text Available Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene, the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA via methacrolein (a C4-unsaturated aldehyde under urban high-NOx conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN as the important intermediate to isoprene and methacrolein SOA in this NOx regime. Here we show that as a result of this chemistry, NO2 enhances SOA formation from methacrolein and two other α, β-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NOx effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are α, β-unsaturated and contain an additional methyl group on the α-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232 is insignificant, even under high-NO2 conditions, as PAN (peroxy acyl nitrate, RC(OOONO2 formation is structurally unfavorable. At atmospherically relevant NO2/NO ratios, the SOA yields from isoprene high-NOxphotooxidation are 3 times greater than previously measured at lower NO2/NO ratios. At sufficiently high NO2 concentrations, in systems of α, β-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO2 can exceed that from RO2+HO2 reactions under the same inorganic seed conditions, making RO2+NO2 an important channel for SOA formation.

  16. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    Directory of Open Access Journals (Sweden)

    P. O. Wennberg

    2010-08-01

    Full Text Available Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene, the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA via methacrolein (a C4-unsaturated aldehyde under urban high-NOx conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN as the important intermediate to isoprene and methacrolein SOA in this NOx regime. Here we show that as a result of this chemistry, NO2 enhances SOA formation from methacrolein and two other α, β-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NOx effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are α, β-unsaturated and contain an additional methyl group on the α-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232 is insignificant, even under high-NO2 conditions, as PAN (peroxy acyl nitrate, RC(OOONO2 formation is structurally unfavorable. At atmospherically relevant NO2/NO ratios (3–8, the SOA yields from isoprene high-NOx photooxidation are 3 times greater than previously measured at lower NO2/NO ratios. At sufficiently high NO2 concentrations, in systems of α, β-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO2 can exceed that from RO2+HO2 reactions under the same inorganic seed conditions, making RO2+NO2 an important channel for SOA formation.

  17. Role of oxidant stress in rheumatoid arthritis

    OpenAIRE

    GS, Lekshmi; BR, Suchit Roy; K., Parvathy; K., Geetha Damodaran

    2015-01-01

    Oxygen derived free radicals have been implicated in the causation of Rheumatoid arthritis (RA) [1].In this study, evidence of free radical injury and oxidative stress in patients with RA is compared with healthy subjects by estimating superoxide dismutase (SOD) and catalase, which are anti-oxidant enzymes in RBCs, Glucose 6 Phosphate Dehydrogenase (G6PD) in RBCs and serum Malon-di-aldehyde (MDA) levels. Serum MDA levels in RA could be used as a biochemical marker of disease activity and for ...

  18. Determination of plutonium oxidation states at trace levels pertinent to nuclear waste disposal

    International Nuclear Information System (INIS)

    A scheme was developed for the determination of oxidation states of plutonium in environmental samples. The method involves a combination of solvent extractions and coprecipitation. It was tested on solutions with both high-level and trace-level concentrations. The scheme was used to determine Pu oxidation states in solutions from solubility experiments in groundwater from a potential nuclear waste disposal site. At steady-state conditions, Pu was found to be soluble predominantly as Pu(V) and Pu(VI)

  19. Hypoxia and oxidation levels of DNA and lipids in humans and animal experimental models

    DEFF Research Database (Denmark)

    Møller, Peter; Risom, Lotte; Lundby, Carsten;

    2008-01-01

    The objective of this review was to evaluate the association between hypoxia and oxidative damage to DNA and lipids. Evaluation criteria encompassed specificity and validation status of the biomarkers, study design, strength of the association, dose-response relationship, biological plausibility......, analogous exposures, and effect modification by intervention. The collective interpretation indicates persuasive evidence from the studies in humans for an association between hypoxia and elevated levels of oxidative damage to DNA and lipids. The levels of oxidatively generated DNA lesions and lipid...... in subjects at high altitude. Most of the animal experimental models should be interpreted with caution because the assays for assessment of lipid peroxidation products have suboptimal validity....

  20. Neuroprotective effects of protocatechuic aldehyde against neurotoxin-induced cellular and animal models of Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Xin Zhao

    Full Text Available Protocatechuic aldehyde (PAL has been reported to bind to DJ-1, a key protein involved in Parkinson's disease (PD, and exerts potential neuroprotective effects via DJ-1 in SH-SY5Y cells. In this study, we investigated the neuroprotective pharmacological effects of PAL against neurotoxin-induced cell and animal models of PD. In cellular models of PD, PAL markedly increased cell viability rates, mitochondrial oxidation-reduction activity and mitochondrial membrane potential, and reduced intracellular ROS levels to prevent neurotoxicity in PC12 cells. In animal models of PD, PAL reduced the apomorphine injection, caused turning in 6-OHDA treated rats, and increased the motor coordination and stride decreases in MPTP treated mice. Meanwhile, in an MPTP mouse model, PAL prevented a decrease of the contents of dopamine (DA and its metabolites in the striatum and TH-positive dopaminergic neuron loss in the substantia nigra (SN. In addition, PAL increased the protein expression of DJ-1 and reduced the level of α-synuclein in the SN of MPTP lesioned mice. PAL also increased the spine density in hippocampal CA1 neurons. The current study demonstrates that PAL can efficiently protect dopaminergic neurons against neurotoxin injury in vitro and in vivo, and that the potential mechanisms may be related to its effects in increasing DJ-1, decreasing α-synuclein and its growth-promoting effect on spine density.

  1. Inhibitory effects of Ruta graveolens L. extract on guinea pig liver aldehyde oxidase.

    Science.gov (United States)

    Pirouzpanah, Saieed; Saieed, Pirouzpanah; Rashidi, Mohammad Reza; Reza, Rashidi Mohammad; Delazar, Abbas; Abbas, Delazar; Razavieh, Seyyed-Vali; Seyyedvali, Razavieh; Hamidi, Aliasghar; Aliasghar, Hamidi

    2006-01-01

    Ruta graveolens L. is a flavonoid-containing medicinal plant with various biological properties. In the present study, the effects of R. graveolens extract on aldehyde oxidase, a molybdenum hydroxylase, are investigated. Aldehyde oxidase was partially purified from liver homogenates of mature male guinea pigs by heat treatment and ammonium sulphate precipitation. The total extract was obtained by macerating the aerial parts of R. graveolens in MeOH 70% and the effect of this extract on the enzyme activity was assayed using phenanthridine, vanillin and benzaldehyde as substrates. Quercetin and its glycoside form, rutin were isolated, purified and identified from the extract and their inhibitory effects on the enzyme were investigated. R. graveolens extract exhibited a high inhibition on aldehyde oxidase activity (89-96%) at 100 microg/ml which was comparable with 10 microM of menadione, a specific potent inhibitor of aldehyde oxidase. The IC50 values for the inhibitory effect of extract against the oxidation of benzaldehyde, vanillin and phenanthridine were 10.4, 10.1, 43.2 microg/ml, respectively. Both quercetin and rutin at 10 microM caused 70-96% and 27-52% inhibition on the enzyme activity, respectively. Quercetin was more potent inhibitor than rutin, but both flavonols exerted their inhibitory effects mostly in a linear mixed-type.

  2. Study on physico-chemical properties of dialdehyde yam starch with different aldehyde group contents

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Liming, E-mail: zhanglmd@yahoo.com.cn [Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457 (China); Liu, Peng; Wang, Yugao [College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China); Gao, Wenyuan [Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457 (China)

    2011-01-10

    Dialdehyde yam starches (DASs) are prepared and characterized. Compared with native starch, viscosity average molecular weight of DASs decreases, and the extent of degradation depends on content of the aldehyde groups. Fourier transform infrared (FT-IR) spectra confirm that the characteristic peak for C=O group at 1732 cm{sup -1} is enhanced with the increasing of content of the aldehyde groups. Scanning electron microscopy (SEM) micrographs show that the surface of starch granules becomes wrinkled. X-ray diffraction (XRD) patterns clearly indicate that their crystallinity decreases with the increasing content of the aldehyde groups before they become amorphous at higher oxidation states. The experimental results of thermogravimetric analysis (TGA) show that DASs have poor stability as compared to native starch. With the increase in content of the aldehyde groups, the thermal stability of DAS declines gradually. According to the results of differential scanning calorimetry (DSC), gelatinization temperature (T{sub o} and T{sub p}) of DASs are increased, whereas the gelatinization enthalpy decreased.

  3. Effect of glutathione on brain nitric oxide levels in an experimental epilepsy mouse model

    Institute of Scientific and Technical Information of China (English)

    Aylin Akcali; Sadrettin Pence; Naciye Kurtul; Mehmet Bosnak; Munife Neyal

    2009-01-01

    BACKGROUND: Oxidative stress plays an important role in the pathophysiology of epilepsy. Glutathione, known as one of the compounds of antioxidant defense, has been shown to inhibit convulsions. Nitric oxide has a proconvulsant effect on a pentylenetetrazole-induced animal model. OBJECTIVE: To evaluate the effects of glutathione administration on nitric oxide levels in brain regions of convulsive and kindling pentylenetetrazole-induced seizure models. DESIGN, TIME, AND SETTING: A randomized, controlled, animal experiment. The study was performed at the Department of Physiology, Gaziantep University and Department of Chemistry-Biochemistry, Kahramamaras Sutcu Imam University in 2006.MATERIALS: Pentylenetetrazole and glutathione were purchased from Sigma, USA. METHODS: A total of 80 mice were assigned to 8 groups (n=10): normal control, saline control (1 mL normal saline), convulsive pentylenetetrazole (single intraperitoneal administration of pentylenetetrazole, 60 mg/kg), convulsive pentylenetrazole plus glutathione (single administration of 60 mg/kg pentylenetetrazole and 200 mg/kg glutathione), five-dose glutathione (intraperitoneal injection of 200 mg/kg glutathione respectively at 1, 3, 5, 7, and 10 days), single-dose glutathione (single administration of 200 mg/kg glutathione), pentylenetetrazole kindling (intraperitoneal administration of pentylenetetrazole of 40 mg/kg at 1, 3, 5, 7, and 10 days), and pentylenetetrazole kindling plus glutathione group (intraperitoneal injection of 40 mg/kg pentylenetetrazole and 200 mg/kg glutathione respectively at 1, 3, 5, 7, and 10 days). MAIN OUTCOME MEASURES: All mice were sacrificed 1 hour after the last administration. Brain nitric oxide levels were determined by spectrophotometry. RESULTS: There were no significant differences in nitric oxide levels between the normal control, saline control, five-dose glutathione, and single-dose glutathione groups (P>0.05). Nitric oxide levels in the cerebral hemisphere and

  4. Cough and exhaled nitric oxide levels: What happens with exercise?

    Directory of Open Access Journals (Sweden)

    Helen ePetsky

    2013-10-01

    Full Text Available Cough associated with exertion is often used as a surrogate marker of asthma. However, to date there are no studies that have objectively measured cough in association with exercise in children. Our primary aim was to examine whether children with a pre-existing cough have an increase in cough frequency during and post-exercise. We hypothesised that children with any coughing illness will have an increase in cough frequency post-exercise regardless of the presence of exercise induced broncho-constriction (EIB or atopy. In addition, we hypotheised that FeNO levels decreases post-exercise regardless of the presence of EIB or atopy.Children with chronic cough and a control group without cough undertook an exercise challenge, FeNO measurements and a skin prick test and wore a 24-hour voice recorder to objectively measure cough frequency. The association between recorded cough frequency, exercise, atopy and presence of EIB was tested. We also determined if the change in FeNO post exercise related to atopy or EIB.Of the 50 children recruited (35 with cough, 15 control, 7 had EIB. Children with cough had a significant increase in cough counts (median 7.0, IQR 0.5, 24.5 compared to controls (2.0, IQR 0, 5.0, p=0.028 post-exercise. Presence of atopy or EIB did not influence cough frequency. FeNO level was significantly lower post-exercise in both groups but the change was not influenced by atopy or EIB. Cough post-exertion is likely a generic response in children with a current cough. FeNO level decreases post-exercise irrespective of the presence of atopy or EIB. A larger study is necessary confirm or refute our findings.

  5. Decreased melatonin levels and increased levels of advanced oxidation protein products in the seminal plasma are related to male infertility.

    Science.gov (United States)

    Kratz, Ewa Maria; Piwowar, Agnieszka; Zeman, Michal; Stebelová, Katarína; Thalhammer, Theresia

    2016-03-01

    Melatonin, an indolamine secreted by the pineal gland, is known as a powerful free-radical scavenger and wide-spectrum antioxidant. Therefore, the aim of this study was to correlate markers of oxidative protein damage (advanced oxidation protein products, AOPPs) and the total antioxidant capacity (TAC) with melatonin levels in the seminal plasma of men with azoospermia (n=37), theratozoospermia (n=29) and fertile controls (normozoospermia, n=37). Melatonin concentration was measured by radioimmunoassay. The levels of AOPP as well as TAC efficiency (determined by the ferric reducing antioxidant power, FRAP) were estimated by spectrophotometric methods. The concentration of melatonin and AOPP significantly differed in azoospermic (P<0.0001) and theratozoospermic (P<0.0001) patients versus fertile men, and correlated negatively (r=-0.33, P=0.0016). The TAC levels were significantly higher in azoospermia than in theratozoospermia (P=0.0022) and the control group (P=0.00016). In azoospermia, the AOPP concentration was also significantly higher than that observed in theratozoospermia (P=0.00029). Decreased levels of melatonin together with elevated AOPP altered the oxidative-antioxidative balance in the ejaculate, thereby reducing fertility. Therefore, melatonin and AOPP levels may serve as additional diagnostic markers of semen quality and male reproductive potential. PMID:25218686

  6. Emissions of aldehydes and ketones from a two-stroke engine using ethanol and ethanol-blended gasoline as fuel.

    Science.gov (United States)

    Magnusson, Roger; Nilsson, Calle; Andersson, Barbro

    2002-04-15

    Besides aliphatic gasoline, ethanol-blended gasoline intended for use in small utility engines was recently introduced on the Swedish market. For small utility engines, little data is available showing the effects of these fuels on exhaust emissions, especially concerning aldehydes and ketones (carbonyls). The objective of the present investigation was to study carbonyl emissions and regulated emissions from a two-stroke chain saw engine using ethanol, gasoline, and ethanol-blended gasoline as fuel (0%, 15%, 50%, 85%, and 100% ethanol). The effects of the ethanol-blending level and mechanical changes of the relative air/fuel ratio, lambda, on exhaust emissions was investigated, both for aliphatic and regular gasoline. Formaldehyde, acetaldehyde, and aromatic aldehydes were the most abundant carbonyls in the exhaust. Acetaldehyde dominated for all ethanol-blended fuels (1.2-12 g/kWh, depending on the fuel and lambda), and formaldehyde dominated for gasoline (0.74-2.3 g/kWh, depending on the type of gasoline and lambda). The main effects of ethanol blending were increased acetaldehyde emissions (30-44 times for pure ethanol), reduced emissions of all other carbonyls exceptformaldehyde and acrolein (which showed a more complex relation to the ethanol content), reduced carbon monoxide (CO) and ntirogen oxide (NO) emissions, and increased hydrocarbon (HC) and nitrogen dixodie (NO2) emissions. The main effects of increasing lambda were increased emissions of carbonyls and nitrogen oxides (NOx) and reduced CO and HC emissions. When the two types of gasoline are considered, benzaldehyde and tolualdehyde could be directly related to the gasoline content of aromatics or olefins, but also acrolein, propanal, crotonaldehyde, and methyl ethyl ketone mainly originated from aromatics or olefins, while the main source for formaldehyde, acetaldehyde, acetone, methacrolein, and butanal was saturated aliphatic hydrocarbons.

  7. T-786c Polymorphism in nitric oxide synthase 3 gene and Nitrit Oxide Level of Diabetic Retinopathy in Javanese Population

    Directory of Open Access Journals (Sweden)

    Putri Widelia Welkriana

    2015-11-01

    Full Text Available AbstractComplication of retinopathy in type 2 DM is caused of lower level of NO. Nitric oxide level is synthesizedfrom L-arginin in reaction that catalyze Nitric oxide synthase (NOS 3. The T-786C mutation in NOS 3 genedecreases the expression of nitric oxide synthase (NOS 3 so decreases NO synthesis. To investigate theassociation between T-786C polymorphism in NOS 3 gene with NO level of diabetic retinopathy patients. Thisstudy was a case control study, consist of 40 patient of type 2 diabetic with DR (case group and 40 patient oftype 2 diabetic without DR (control group of Javanese ethnic. The genotyping of T-786C polymorphism wasperformed by PCR-RLFP. Level of NO was measured by spectrophotometry. Chi square test and odd ratiowere used to analyze the association of the T-786C polymorphism in NOS 3 gene with DR. Differences ofNO level between TT and TC genotypes were analyzed using independent t test. The distribution of T-786Cpolymorphism in NOS 3 gene of DR subjects showed that frequency of TT genotype was 22.5% and TC genotypewas 77.5%. Non DR subjects showed the frequency of TT genotype was 50% and TC genotype was 50%, (p=0.011. Frequency of T allele in DR group was 61.25% and C allele was 38.75%, and frequency of T allele in nonDR group was 75% and C allele was 25%, (p= 0.62. Odd ratio of TC genotype was 3.444(CI; 95% : 0.964-3.735and C allele was 1.898 (CI; 95% : 1.310-9.058. The NO level of TC genotype was 1.43+0.126 and TT genotypewas 11.27+5.87 (p=0.000. Level of NO between RD and non RD showed not different significantly (p=0.160for retinopathy. The T-786C polymorphism of NOS 3 gene is risk factor for retinopathy in type 2 DiabetesMellitus. Individual with TC genotype of NOS 3 gene has lower level of NO than TT genotype.Keywords : Diabetic Retinopathy, Polymorphism, Nitric Oxide, Nitric Oxide Synthase.

  8. Biogenic aldehyde determination by reactive paper spray ionization mass spectrometry

    International Nuclear Information System (INIS)

    Highlights: • In-situ derivatization and simultaneous ionization used to detect aldehydes. • Biogenic aliphatic and aromatic aldehydes reacted with 4-aminophenol. • Derivatized products yield structurally characteristic fragment ions. • This measurement demonstrated using a miniaturized portable mass spectrometer. - Abstract: Ionization of aliphatic and aromatic aldehydes is improved by performing simultaneous chemical derivatization using 4-aminophenol to produce charged iminium ions during paper spray ionization. Accelerated reactions occur in the microdroplets generated during the paper spray ionization event for the tested aldehydes (formaldehyde, n-pentanaldehyde, n-nonanaldehyde, n-decanaldehyde, n-dodecanaldehyde, benzaldehyde, m-anisaldehyde, and p-hydroxybenzaldehyde). Tandem mass spectrometric analysis of the iminium ions using collision-induced dissociation demonstrated that straight chain aldehydes give a characteristic fragment at m/z 122 (shown to correspond to protonated 4-(methyleneamino)phenol), while the aromatic aldehyde iminium ions fragment to give a characteristic product ion at m/z 120. These features allow straightforward identification of linear and aromatic aldehydes. Quantitative analysis of n-nonaldehyde using a benchtop mass spectrometer demonstrated a linear response over 3 orders of magnitude from 2.5 ng to 5 μg of aldehyde loaded on the filter paper emitter. The limit of detection was determined to be 2.2 ng for this aldehyde. The method had a precision of 22%, relative standard deviation. The experiment was also implemented using a portable ion trap mass spectrometer

  9. Biogenic aldehyde determination by reactive paper spray ionization mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bag, Soumabha; Hendricks, P.I. [Aston Labs, Department of Chemistry, Purdue University, West Lafayette, IN 47907 (United States); Reynolds, J.C. [Centre for Analytical Science, Loughborough University, Loughborough, Leicestershire (United Kingdom); Cooks, R.G., E-mail: cooks@purdue.edu [Aston Labs, Department of Chemistry, Purdue University, West Lafayette, IN 47907 (United States)

    2015-02-20

    Highlights: • In-situ derivatization and simultaneous ionization used to detect aldehydes. • Biogenic aliphatic and aromatic aldehydes reacted with 4-aminophenol. • Derivatized products yield structurally characteristic fragment ions. • This measurement demonstrated using a miniaturized portable mass spectrometer. - Abstract: Ionization of aliphatic and aromatic aldehydes is improved by performing simultaneous chemical derivatization using 4-aminophenol to produce charged iminium ions during paper spray ionization. Accelerated reactions occur in the microdroplets generated during the paper spray ionization event for the tested aldehydes (formaldehyde, n-pentanaldehyde, n-nonanaldehyde, n-decanaldehyde, n-dodecanaldehyde, benzaldehyde, m-anisaldehyde, and p-hydroxybenzaldehyde). Tandem mass spectrometric analysis of the iminium ions using collision-induced dissociation demonstrated that straight chain aldehydes give a characteristic fragment at m/z 122 (shown to correspond to protonated 4-(methyleneamino)phenol), while the aromatic aldehyde iminium ions fragment to give a characteristic product ion at m/z 120. These features allow straightforward identification of linear and aromatic aldehydes. Quantitative analysis of n-nonaldehyde using a benchtop mass spectrometer demonstrated a linear response over 3 orders of magnitude from 2.5 ng to 5 μg of aldehyde loaded on the filter paper emitter. The limit of detection was determined to be 2.2 ng for this aldehyde. The method had a precision of 22%, relative standard deviation. The experiment was also implemented using a portable ion trap mass spectrometer.

  10. A coniferyl aldehyde dehydrogenase gene from Pseudomonas sp. strain HR199 enhances the conversion of coniferyl aldehyde by Saccharomyces cerevisiae.

    Science.gov (United States)

    Adeboye, Peter Temitope; Olsson, Lisbeth; Bettiga, Maurizio

    2016-07-01

    The conversion of coniferyl aldehyde to cinnamic acids by Saccharomyces cerevisiae under aerobic growth conditions was previously observed. Bacteria such as Pseudomonas have been shown to harbor specialized enzymes for converting coniferyl aldehyde but no comparable enzymes have been identified in S. cerevisiae. CALDH from Pseudomonas was expressed in S. cerevisiae. An acetaldehyde dehydrogenase (Ald5) was also hypothesized to be actively involved in the conversion of coniferyl aldehyde under aerobic growth conditions in S. cerevisiae. In a second S. cerevisiae strain, the acetaldehyde dehydrogenase (ALD5) was deleted. A prototrophic control strain was also engineered. The engineered S. cerevisiae strains were cultivated in the presence of 1.1mM coniferyl aldehyde under aerobic condition in bioreactors. The results confirmed that expression of CALDH increased endogenous conversion of coniferyl aldehyde in S. cerevisiae and ALD5 is actively involved with the conversion of coniferyl aldehyde in S. cerevisiae. PMID:27070284

  11. Modulating nitric oxide levels in dorsal root ganglion neurons of rat with low-level laser therapy

    Science.gov (United States)

    Zheng, Li-qin; Wang, Yu-hua; He, Yi-peng; Zhou, Jie; Yang, Hong-qin; Zhang, Yan-ding; Xie, Shu-sen

    2015-05-01

    Nitric oxide (NO) and nitric oxide synthase (NOS) have an important role in pain signaling transmission in animal models. Low-level laser therapy (LLLT) is known to have an analgesic effect, but the mechanism is unclear. The aim of the study is to investigate the influence of LLLT on NO release and NOS synthesis in dorsal root ganglion (DRG) neurons, in order to find whether LLLI can ameliorate pain through modulating NO production at the cellular level. The results show that in stress conditions, the laser irradiation at 658 nm can modulate NO production in DRG neurons with soma diameter of about 20 μm in a short time after illumination, and affect NOS synthesis in a dose-dependent manner. It is demonstrated that LLLT might treat pain by altering NO release directly and indirectly in DRG neurons.

  12. Evaluation of Salivary Nitric Oxide Levels in Smokers, Tobacco Chewers and Patients with Oral Lichenoid Reactions

    Science.gov (United States)

    Jose, Joy Idiculla; Sivapathasundharam, B.; Sabarinath, B.

    2016-01-01

    Introduction Nitric oxide (NO), a free radical, acts as a signalling molecule affecting numerous physiological and pathological processes. Role of nitric oxide as a mediator in tobacco related habits and the resultant oral lichenoid reactions was assessed. Aim The aim of the study is to evaluate and compare the salivary nitric oxide levels in normal patients with that of smokers, tobacco chewers and patients with oral lichenoid reactions. Materials and Methods One hundred and twenty patients were enrolled in the study which included 30 healthy patients without any chronic inflammatory lesion and habit as controls (group I), 30 smokers without the habit of tobacco/betel nut chewing and any oral lesion (group II), 30 tobacco chewers without the habit of smoking and any oral lesion (group III) and 30 histologically confirmed cases of oral lichenoid reaction with the habit of tobacco usage (group IV). Saliva from these patients was collected and the nitrite concentration was assessed. Results Our results concluded that there was highly significant increase in the nitric oxide levels in smokers, tobacco chewers and patients with oral lichenoid reactions compared to that of controls. Also, there was a significant increase in nitric oxide levels in patients with smoking associated oral lichenoid reactions in comparison with smokers and in patients with lichenoid reactions associated with tobacco chewing in comparison with tobacco chewers. Conclusion Estimation of salivary nitric oxide levels is a simple, non-invasive procedure and could be analysed to suggest the role of nitric oxide in the pathogenesis of these lesions. The increased activity of the enzyme may indicate that nitric oxide has a pathophysiological role in these lesions. PMID:26894179

  13. Serum Levels of Melatonin and Oxidative Stress Markers and Correlation between Them in Infertile Men

    OpenAIRE

    Sara Soleimani Rad; Shamsi Abbasalizadeh; Amir Ghorbani Haghjo

    2013-01-01

    Introduction: Infertility is the problem of 15% of young couples in different societies. One of the factors that could affect fertility is oxidative stress. Therefore, the aim of the present study is to investigate the level of Melatonin, a free radical scavenger, and its correlation with oxidative biomarkers in infertile men. Methods:For this purpose, fertile and infertile men in 2 groups, 30 people in each group, were studied. The fertile men were selected from husbands of patients admitted...

  14. Serum Levels of Melatonin and Oxidative Stress Markers and Correlation between Them in Infertile Men

    OpenAIRE

    Soleimani Rad, Sara; Abbasalizadeh, Shamsi; Ghorbani Haghjo, Amir; Sadagheyani, Mehzad; Montaseri, Azadeh; Soleimani Rad, Jafar

    2013-01-01

    Introduction: Infertility is the problem of 15% of young couples in different societies. One of the factors that could affect fertility is oxidative stress. Therefore, the aim of the present study is to investigate the level of Melatonin, a free radical scavenger, and its correlation with oxidative biomarkers in infertile men. Methods: For this purpose, fertile and infertile men in 2 groups, 30 people in each group, were studied. The fertile men were selected from husbands o...

  15. The Effected Oxide Capacitor in CMOS Structure of Integrated Circuit Level 5 Micrometer Technology

    OpenAIRE

    Rodthong, S.; Burapattanasiri, B.

    2009-01-01

    This article is present the effected oxide capacitor in CMOS structure of integrated circuit level 5 micrometer technology. It has designed and basic structure of MOS diode. It establish with aluminum metallization layer by sputtering method, oxide insulator layer mode from silicon dioxide, n+ and p+ semiconductor layer, it has high capacitance concentrate. From the MOS diode structure silicon dioxide thickness 0.5 micrometer, it will get capacitance between aluminum metal layer and p+ semico...

  16. Comments on "thermal degradation behavior of hypochlorite-oxidized starch nanocrystals under different oxidized levels".

    Science.gov (United States)

    Trache, Djalal

    2016-10-20

    This paper intends to discuss the employment of the Coats-Redfern equation to compute the kinetic parameters of the thermal degradation of hypochlorite-oxidized starch nancrystals by Wei et al. [Carbohydrate Polymers 124 (2015) 124-130]. The original paper has shown some fundamental errors when presenting the Coats-Redfern (CR) integral kinetic model. This CR equation is commonly used to calculate the activation energy of the thermal degradation from a single non isothermal thermogravimetric curve. However, the use of a set of experiments recorded under different heating rates is often required to obtain accurate results, as recommended by the International Confederation for Thermal Analysis and Calorimetry (ICTAC) Kinetics Committee. The present comments are focused on these statements giving some arguments and elucidations concerning the Coats-Redfern equation.

  17. Comments on "thermal degradation behavior of hypochlorite-oxidized starch nanocrystals under different oxidized levels".

    Science.gov (United States)

    Trache, Djalal

    2016-10-20

    This paper intends to discuss the employment of the Coats-Redfern equation to compute the kinetic parameters of the thermal degradation of hypochlorite-oxidized starch nancrystals by Wei et al. [Carbohydrate Polymers 124 (2015) 124-130]. The original paper has shown some fundamental errors when presenting the Coats-Redfern (CR) integral kinetic model. This CR equation is commonly used to calculate the activation energy of the thermal degradation from a single non isothermal thermogravimetric curve. However, the use of a set of experiments recorded under different heating rates is often required to obtain accurate results, as recommended by the International Confederation for Thermal Analysis and Calorimetry (ICTAC) Kinetics Committee. The present comments are focused on these statements giving some arguments and elucidations concerning the Coats-Redfern equation. PMID:27474597

  18. EVALUATION OF ISCHEMIA MODIFIED ALBUMIN AND NITRIC OXIDE LEVELS AND THEIR INTER - RELATIONSHIP IN HYPERTHYROIDISM

    Directory of Open Access Journals (Sweden)

    Rangaswamy

    2014-02-01

    Full Text Available BACKGROUND: Ischemia Modified Albumin (IMA is an ischemia/reperfusion injury marker which has been considered to be formed under oxidative stress conditions. Endothelial L - Arginine/NO pathway dysfunction can lead to oxidative stress which has deleterious effects seen on the vascular wall causing ischemia. AIM: 1 The study was conducted to estimate the levels of IMA and NO in hyperthyroidism patients. 2 To evaluate the relationship bet ween IMA and NO levels in hyperthyroidism. MATERIALS AND METHODS: A cross sectional study was done with 30 newly diagnosed hyperthyroid patients as cases and 30 age and sex matched healthy controls. Serum levels of IMA and NO were estimated by colorimetric methods and thyroid profile was done by ELIFA methodology. STATISTICAL ANALYSIS: Data were analyzed using SPSS. Values were expressed as Mean±SD. RESULTS: Nitric Oxide levels were significantly decreased in hyperthyroid patients (7.08±1.57μmol/L as compa red to healthy controls (39.76±4.98μmol/L (p=0.001. Ischemia Modified Albumin levels were found to be significantly increased in hyperthyroid patients (0.73±0.10 ODU when compared to healthy controls (0.28±0.01 ODU (p=0.001. CONCLUSION: In our study t here was increase in IMA levels with decreased NO levels which could be due to the consequence of oxidative stress and ischemia which is present in hyperthyroidism

  19. Oxidative stress may explain how hypertension is maintained by normal levels of angiotensin II

    Directory of Open Access Journals (Sweden)

    J.C. Romero

    2000-06-01

    Full Text Available It is well known that essential hypertension evolves in most patients with "near normal" levels of plasma renin activity. However, these levels appear to be responsible for the high levels of arterial pressure because they are normalized by the administration of angiotensin II converting inhibitors or angiotensin receptor antagonist. In experimental animals, hypertension can be induced by the continuous intravenous infusion of small doses of angiotensin II that are not sufficient to evoke an immediate pressor response. However, this condition resembles the characteristics of essential hypertension because the high levels of blood pressure exist with normal plasma levels of angiotensin II. It is suggested that small amounts of angiotensin whose plasma levels are inappropriate for the existing size of extracellular volume stimulate oxidative stress which binds nitric oxide forming peroxynitrite. The latter compound oxidizes arachidonic acid producing isoprostaglandin F2a (an isoprostane which is characterized by a strong antinatriuretic vasoconstrictor renal effect. In this chain of reactions the vasoconstrictor effects derived from oxygen quenching of nitric oxide and increased isoprostane synthesis could explain how hypertension is maintained with normal plasma levels of renin.

  20. Nitrous Oxide Levels In Operating and Recovery Rooms of Iranian Hospitals

    Directory of Open Access Journals (Sweden)

    Sh Sadigh Maroufi

    2011-06-01

    Full Text Available "nBackground: Nitrous oxide (N2O is the oldest anesthetic in routine clinical use and its occupational exposure is under regulation by many countries. As studies are lacking to demonstrate the status of nitrous oxide levels in operating and recovery rooms of Iranian hospitals, we aimed to study its level in teaching hospitals of Tehran University of Medical Sciences."nMethods: During a 6-month period, we have measured the shift-long time weighted average concentration of N2O in 43 op­erating and 12 recovery rooms of teaching hospitals of Tehran University of Medical Sciences."nResults: The results show that the level of nitrous oxide in all hospitals is higher than the limits set by different countries and anesthetists are at higher risk of exposure. In addition, it was shown that installation of air ventilation could reduce not only the overall exposure level, but also the level of exposure of anesthetists in comparison with other personnel."nConclusion: The high nitrous oxide level in Iranian hospitals necessitates improvement of waste gas evacuation systems and regular monitoring to bring the concentration of this gas into the safe level.

  1. A wafer-level liquid cavity integrated amperometric gas sensor with ppb-level nitric oxide gas sensitivity

    Science.gov (United States)

    Gatty, Hithesh K.; Stemme, Göran; Roxhed, Niclas

    2015-10-01

    A miniaturized amperometric nitric oxide (NO) gas sensor based on wafer-level fabrication of electrodes and a liquid electrolyte chamber is reported in this paper. The sensor is able to detect NO gas concentrations of the order of parts per billion (ppb) levels and has a measured sensitivity of 0.04 nA ppb-1 with a response time of approximately 12 s. A sufficiently high selectivity of the sensor to interfering gases such as carbon monoxide (CO) and to ammonia (NH3) makes it potentially relevant for monitoring of asthma. In addition, the sensor was characterized for electrolyte evaporation which indicated a sensor operation lifetime allowing approximately 200 measurements.

  2. Elevated levels of nitric oxide and low levels of haptoglobin are associated with severe malarial anaemia in African children

    DEFF Research Database (Denmark)

    Gyan, Ben; Kurtzhals, Jørgen; Akanmori, Bartholomew D;

    2002-01-01

    Severe malarial anaemia (SA) is a major complication of malaria and an important cause of child mortality and morbidity. However, the pathogenesis behind SA is poorly understood. Nitric oxide (NO) is known to play a protective role against clinical malaria but is also suggested to have a pathogenic...... was there any correlation between parasitaemias and neopterin levels. The low haptoglobin and high levels of NO in this SA group may contribute to haemolysis. Taken together our results support the hypothesis that immune-mediated erythrocyte destruction is involved in the pathogenesis of malarial anaemia....

  3. Antioxidant enzymatic defenses and oxidative damage in Dentex dentex fed on different dietary macronutrient levels.

    Science.gov (United States)

    Pérez-Jiménez, Amalia; Hidalgo, M Carmen; Morales, Amalia E; Arizcun, Marta; Abellán, Emilia; Cardenete, Gabriel

    2009-11-01

    A wide range of antioxidant mechanisms are present in fish maintaining an adequate "oxidative balance". When this balance tilts in favor of the oxidant agents "oxidative stress" arises with detrimental effects in molecules of great biological importance. Little has been reported about the influence of different dietary energy sources on antioxidant defenses in fish. The influence of different dietary macronutrient combinations on the key antioxidant enzyme activity, the oxidative damage to lipids and proteins and the possible modifications in the SOD isoenzymatic pattern were evaluated in liver, white muscle, heart and erythrocytes of common dentex (Dentex dentex). Four experimental diets with different protein:lipid:carbohydrate ratios (43/16/28; 43/24/4; 38/19/28 and 38/24/13) were formulated. In general, neither different dietary macronutrient levels nor the interaction among them induces substantial modifications in enzymatic antioxidant defense mechanisms. Two constitutive SOD isoforms, CuZn-SOD I and Mn-SOD, were detected in the tissues analyzed in all experimental groups, independently of diet formulation, but, a third SOD isoenzyme, CuZn-SOD II seems to be induced in white muscle by higher dietary protein levels. Densitometric analyses of western blotting membranes revealed higher CuZn-SOD expression in the heart of dentex fed on lower dietary protein levels, although these differences did not correlate with the SOD activity. Finally, a direct relation exists between the lipid or protein intake level and occurrence of oxidative damage in different tissue components.

  4. Antioxidant factors, nitric oxide levels, and cellular damage in leprosy patients

    Directory of Open Access Journals (Sweden)

    Taysa Ribeiro Schalcher

    2013-09-01

    Full Text Available Introduction The immune response caused by Mycobacterium leprae is a risk factor for the development of oxidative stress (OS in leprosy patients. This study aimed to assess OS in leprosy patients before the use of a multidrug therapy. Methods We evaluated the nitric oxide (NO concentration; antioxidant capacity; levels of malondialdehyde, methemoglobin and reduced glutathione; and the activity of catalase and superoxide dismutase (SOD in leprosy patients. Results We observed lower SOD activity in these leprosy patients; however, the NO levels and antioxidant capacity were increased. Conclusions The infectious process in response to M. leprae could primarily be responsible for the OS observed in these patients.

  5. Reactivity of TEMPO anion as a nucleophile and its applications for selective transformations of haloalkanes or acyl halides to aldehydes

    OpenAIRE

    Inokuchi, Tsutomu; Kawafuchi, Hiroyuki

    2004-01-01

    Sodium 2,2,6,6-tetramethylpiperidine-N-oxide (TEMPO−Na+), generated by reduction of TEMPO· with sodium naphthalenide in THF, reacted with alkyl halides or acyl halides to produce O-alkylated or acylated TEMPOs, which were in turn oxidized with mCPBA or reduced with DIBAL-H to afford the corresponding aldehydes, thus accomplishing a new protocol for the halides-carbonyls conversion.

  6. Exhaled nitric oxide levels in exacerbations of asthma, chronic obstructive pulmonary disease and pneumonia

    International Nuclear Information System (INIS)

    Nitric oxide is known to be present in the exhaled air of normal subjects and at higher concentrations in asthmatics. The aim of this study was to measure exhaled nitric oxide levels in patients admitted to hospital with acute exacerbations of asthma, or chronic obstructive pulmonary disease, or with pneumonia. Within 24 hours of admission exhaled nitric oxide levels were measured by a chemiluminescent analyzer in 11 patients with acute sever asthma, 19 patients with acute exacerbation of chronic obstructive pulmonary disease, and in 12 patients with pneumonia. In asthmatics measurements were made on 3 occasions, at day 1, 4, and 28 and were related to changes in peak expiratory flow rate. On admission median exhaled nitric oxide levels (range) were significantly higher in asthmatics 22 (9.3-74) parts per billion in comparison to patients with chronic obstructive pulmonary disease 10.3 (2.7-34) parts per billion; p<0.01, pneumonia 7 (4-17) parts per billion; p<0.001, and normal subjects 8.7 (5-13.3) parts per billion; p<0.001. Following treatment the asthmatics had a significant reduction in their exhaled nitric oxide levels from 22 (9.3-74) parts per billion on day 1 to 9.7 (5.7-18.3) parts per billion on day 28; p=0.005. Peak expiratory flow rate measurements increased from 200 (120-280) l/min on day 1 to 280 (150-475) l/min on day 4; p<0.05 and to 390 (150-530) l/min on day 28; p<0.01. A strong negative correlation existed between peak expiratory flow rate measurements and exhaled nitric oxide levels in asthmatics on day 28 (r=-0.70; p=0.017). Acute exacerbations of asthma are associated with increased levels of exhaled nitric oxide in contrast to exacerbations of chronic obstructive pulmonary disease and acute pneumonia. Exhaled nitric oxide may be a useful indirect marker of asthmatic airway inflammation. The differing time course of response of nitric oxide to peak flow measures suggests that these two measures are reflecting differing airway events. (author)

  7. Ambient concentrations of aldehydes in relation to Beijing Olympic air pollution control measures

    Science.gov (United States)

    Gong, J. C.; Zhu, T.; Hu, M.; Zhang, L. W.; Cheng, H.; Zhang, L.; Tong, J.; Zhang, J.

    2010-08-01

    Aldehydes are ubiquitous constituents of the atmosphere. Their concentrations are elevated in polluted urban atmospheres. The present study was carried out to characterize three aldehydes of most health concern (formaldehyde, acetaldehyde, and acrolein) in a central Beijing site in the summer and early fall of 2008 (from June to October). Measurements were made before, during, and after the Beijing Olympics to examine whether the air pollution control measures implemented to improve Beijing's air quality during the Olympics had any impact on concentrations of the three aldehydes. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.34 ± 15.12 μg/m3, 27.09 ± 15.74 μg/m3 and 2.32 ± 0.95 μg/m3, respectively, for the entire period of measurements, all being the highest among the levels measured in cities around the world in photochemical smog seasons. Among the three measured aldehydes, only acetaldehyde had a substantially reduced mean concentration during the Olympic air pollution control period compared to the pre-Olympic period. Formaldehyde and acrolein followed the changing pattern of temperature and were each significantly correlated with ozone (a secondary product of photochemical reactions). In contrast, acetaldehyde was significantly correlated with several pollutants emitted mainly from local emission sources (e.g., NO2, CO, and PM2.5). These findings suggest that local direct emissions had a larger impact on acetaldehyde than formaldehyde and acrolein.

  8. Fast determination of aldehyde preservatives by miniaturized capillary electrophoresis with amperometric detection.

    Science.gov (United States)

    Li, Ying; Chen, Fang; Ge, Jinyuan; Tong, Fanghong; Deng, Zhaoyue; Shen, Fengwu; Gu, Qianxia; Ye, Jiannong; Chu, Qingcui

    2014-02-01

    A novel miniaturized CE with amperometric detection (mini-CE-AD) method has been developed for fast determination of aliphatic aldehyde preservatives, namely formaldehyde and glyoxal, in commodities. After derivatization with an electroactive compound 2-thiobarbituric acid, these two nonelectroactive aldehydes were converted to electroactive adducts, therefore detectable by mini-CE-AD approach. Under the optimum conditions, two aldehydes can be well-separated with the coexisting interferents as well as their homologs (acetaldehyde and methyl-glyoxal), and the LODs (S/N = 3) were achieved at nanogram-per-milliliter level (1.64-2.80 ng/mL) based on the online enrichment method of transient moving chemical reaction boundary. The proposed method has been applied for the analyses of above aldehyde preservatives in different real commodity samples including skincare products, baby lotion, and toothpaste, and the average recoveries were in the range of 94-105%, which should find a wide range of analytical applications as an alternative to conventional and microchip CE approaches.

  9. Low level laser therapy reduces oxidative stress in cortical neurons in vitro

    Science.gov (United States)

    Huang, Ying-Ying; Tedford, Clark E.; McCarthy, Thomas; Hamblin, Michael R.

    2012-03-01

    It is accepted that the mechanisms of low level laser therapy (LLLT) involves photons that are absorbed in the mitochondria of cells and lead to increase of mitochondrial metabolism resulting in more electron transport, increase of mitochondrial membrane potential, and more ATP production. Intracellular calcium changes are seen that correlate with mitochondrial stimulation. The situation with two other intermediates is more complex however: reactive oxygen species (ROS) and nitric oxide (NO). Evidence exists that low levels of ROS are produced by LLLT in normal cells that can be beneficial by (for instance) activating NF-kB. However high fluences of light can produce large amounts of ROS that can damage the cells. In oxidatively stressed cells the situation may be different. We exposed primary cultured cortical neurons to hydrogen peroxide (H2O2) or cobalt chloride (CoCl2) oxidative insults in the presence or absence of LLLT (810-nm laser at 0.3 or 3 J/cm2). Cell viability of cortical neurons was determined by lactate dehydrogenase assay. ROS in neurons was detected using an ROS probe, MitoRox with confocal microscopy. Results showed that LLLT dose-dependently reversed ROS production and protected cortical neurons against H2O2 or CoCl2 induced oxidative injury in cultured cortical neurons. Conclusion: LLLT can protect cortical neurons against oxidative stress by reversing the levels of ROS.

  10. Molecular-Level Processes Governing the Interaction of Contaminants with Iron and Manganese Oxides - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Brown Jr., G. E.; Chambers, S. A.

    1999-10-31

    Many of the inorganic and organic contaminants present in sediments at DOE sites can be altered or destroyed by reduction and oxidation (redox) reactions occurring at mineral surfaces. A fundamental understanding of such redox processes provided by molecular-level studies on structurally and compositionally well-defined mineral surfaces will lead to: (i) improved models of contaminant fate and transport in geochemical systems, and (ii) optimized manipulation of these processes for remediation purposes. To contribute to this understanding, we will study, both experimentally and theoretically, redox processes involving three important contaminants - chromate ion, carbon tetrachloride, and trichloroethene TCE, on the following iron and manganese oxides - hematite, magnetite, maghemite, and pyrolusite. These oxides and their hydroxylated analogs commonly occur as coatings on minerals or as interfaces in the subsurface environment. Single-crystal surfaces of these oxides will be synthesized in carefully controlled fashion by molecular beam epitaxy. These surfaces, as well as high surface are powdered samples of these oxides, will be used in spectroscopic and kinetic experiments in both aqueous and gas phases. Our goal is to identify products and to determine the kinetics and mechanisms of surface-catalyzed redox reaction of Cr(VI) and CR(III), and the reductive dechlorination of carbon tetrachloride and TCE. The combination of theory and experiment will provide the base information needed to scale from the molecular level to the microscopic grain level minerals.

  11. Effect of Helicobacter pylori infection on gastric mucosal pathologic change and level of nitric oxide and nitric oxide synthase

    Institute of Scientific and Technical Information of China (English)

    Yong-Fu Wang; Chun-Lin Guo; Li-Zhen Zhao; Guo-An Yang; Peng Chen; Hong-Kun Wang

    2005-01-01

    AIM: To investigate the level of nitric oxide (NO) and nitrous oxide synthase (NOS) enzyme and its effect on gastric mucosal pathologic change in patients infected with Helicobacter pylori (H pylori), and to study the pathogenic mechanism of H pylori.METHODS: The mucosal tissues of gastric antrum were taken by endoscopy, then their pathology, H pylori and anti-CagA-IgG were determined. Fifty H pyloripositive cases and 35 H pylori negative cases were randomly chosen.Serum level of NO and NOS was detected.RESULTS: One hundred and seven cases (71.33%) were anti-CagA-IgG positive in 150 H pyloripositive cases. The positive rate was higher especially in those with preneoplastic diseases, such as atrophy, intestinal metaplasia and dysplasia. The level of NO and NOS in positive group was higher than that in negative group, and apparently lower in active gastritis than in pre-neoplastic diseases such as atrophy, intestinal metaplasia and dysplasia.CONCLUSION: H pyloriis closely related with chronic gastric diseases, and type Ⅰ Hpylorimay be the real factor for Hpylori-related gastric diseases. Infection with H pylori can induce elevation of NOS, which produces NO.

  12. Pistachio intake increases high density lipoprotein levels and inhibits low-density lipoprotein oxidation in rats.

    Science.gov (United States)

    Aksoy, Nur; Aksoy, Mehmet; Bagci, Cahit; Gergerlioglu, H Serdar; Celik, Hakim; Herken, Emine; Yaman, Abdullah; Tarakcioglu, Mehmet; Soydinc, Serdar; Sari, Ibrahim; Davutoglu, Vedat

    2007-05-01

    There is increasing evidence that nuts have protective effects against coronary artery disease by improving lipid profile and inhibiting lipid oxidation. However, data about pistachio nuts are limited, and to our knowledge, there is no study investigating the effects of pistachio intake on lipid oxidation and serum antioxidant levels. This study, therefore, sought to determine the effects of pistachio intake on serum lipids and determine whether consumption of pistachio would alter serum antioxidant levels. Rats were randomly divided into three groups (n=12 for each): control group fed basic diet for 10 weeks and treated groups fed basic diet plus pistachio which constituted 20% and 40% of daily caloric intake, respectively. Consumption of pistachio as 20% of daily caloric intake increased high-density lipoprotein (HDL) levels and decreased total cholesterol (TC)/HDL ratio, compared with those not taking pistachio. However, TC, low-density lipoprotein (LDL) cholesterol and triglyceride levels were unaffected by pistachio consumption. Consumption of pistachio as 20% of daily caloric intake increased serum paraoxonase activity by 35% and arylesterase activity by 60%, which are known to inhibit LDL cholesterol oxidation, compared with the control group. However, increased antioxidant activity was blunted when pistachio intake was increased to 40% of daily caloric intake. In conclusion, the present results show that consumption of pistachio as 20% of daily caloric intake leads to significant improvement in HDL and TC/HDL ratio and inhibits LDL cholesterol oxidation. These results suggest that pistachio may be beneficial for both prevention and treatment of coronary artery disease.

  13. Serum uric acid levels and leukocyte nitric oxide production in multiple sclerosis patients outside relapses

    NARCIS (Netherlands)

    Mostert, JP; Ramsaransing, GSM; Heerserna, DJ; Heerings, M; Wilczak, N; De Keyser, J

    2005-01-01

    Background: A number of studies found that patients with multiple sclerosis (MS) have low serum levels of uric acid. It is unclear whether this represents a primary deficit or secondary effect. Uric acid is a scavenger of peroxynitrite, which is the product of nitric oxide (NO) and superoxide. Becau

  14. Study of Foeniculum vulgare (Fennel Seed Extract Effects on Serum Level of Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Sadeghpour Nahid

    2015-04-01

    Full Text Available Objective: The Foeniculum vulgare (FVE, known as fennel, has a long history of herbal uses as both food and medicine. The seed of this plant has been used to promote menstruation, alleviate the symptoms of female climacteric, and increase the number of ovarian follicles. The aim of this study was to evaluate the fennel extract effects on serum level of oxidative stress in female mice. Materials and Methods: Totally, 28 virgin female albino mice were divided into four groups (n = 7. Groups 1 and 2 (experimental groups were administered FVE at 100 and at a concentration of 100 and 200 mg/kg for 5 days, interaperitoneally. Group 3 (negative control received ethanol and Group 4 (positive control received normal saline. Animals were scarified at 6th day, sera were collected and the level of oxidative stress was determination of using total antioxidant status kit. Results: Data analysis revealed that there is a significant difference in the mean level of serum oxidative stress between four different groups. P value in experimental groups compared to the control group was (P < 0.0001. Conclusion: Fennel extract can decrease the serum level of oxidative factors in female mice; it can be introduced as a novel medicine for treatment of infertility

  15. Low-level laser therapy (LLLT) reduces oxidative stress in primary cortical neurons in vitro

    OpenAIRE

    Huang, Ying-Ying; Nagata, Kazuya; Tedford, Clark E.; McCarthy, Thomas; Hamblin, Michael R.

    2012-01-01

    Low-level laser (light) therapy (LLLT) involves absorption of photons being in the mitochondria of cells leading to improvement in electron transport, increased mitochondrial membrane potential (MMP), and greater ATP production. Low levels of reactive oxygen species (ROS) are produced by LLLT in normal cells that are beneficial. We exposed primary cultured murine cortical neurons to oxidative stressors: hydrogen peroxide, cobalt chloride and rotenone in the presence or absence of LLLT (3 J/cm...

  16. Portal pressure and blood nitric oxide levels as predictors of outcome in biliary atresia

    OpenAIRE

    Vikram Khanna; Veereshwar Bhatnagar; Sandeep Agarwala; Maddur Srinivas; Nibhriti Das; Manoj Kumar Singh

    2016-01-01

    Aim: To evaluate the incidence of portal hypertension (PHT) in biliary atresia (BA) patients and to monitor its progress after Kasai portoenterostomy (KP) by measuring nitric oxide (NO) levels in peripheral blood. Materials and Methods: A prospective cross-sectional study conducted over a period of 2 years. Intraoperative portal pressure (PP) and blood NO levels at presentation, 1-month, 3-month, and 6-month follow-up, were correlated with clinical and biochemical parameters in BA patients. T...

  17. Serum Antioxidative Enzymes Levels and Oxidative Stress Products in Age-Related Cataract Patients

    Science.gov (United States)

    Chang, Dong; Zhang, Xuefei; Rong, Shengzhong; Sha, Qian; Liu, Peipei; Han, Tao; Pan, Hongzhi

    2013-01-01

    Purpose. To investigate the activity of antioxidative enzymes and the products of oxidative stress in patients with age-related cataracts and compare the findings with those in healthy control subjects. Method. Sixty patients with age-related cataract and sixty healthy controls of matched age and gender were included in this study. Serum samples were obtained to detect the antioxidative enzymes of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), and oxidation degradation products of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), conjugated diene (CD), advanced oxidation protein products (AOPP), protein carbonyl (PC), and 8-hydroxydeoxyguanosine (8-OHdG). Results. Serum SOD, GSH-Px, and CAT activities in cataract group were significantly decreased as compared to the control subjects (P < 0.05). The levels of MDA, 4-HNE, and CD in cataract patients were significantly higher than those in the control subjects (P < 0.05, P < 0.01). Cataract patients had higher levels of 8-OHdG, AOPP, and PC with respect to the comparative group of normal subjects (P < 0.01). And there was no statistical significance in concentration of antioxidative enzymes and oxidative stress products in patients with different subtype cataract. Conclusions. Oxidative stress is an important risk factor in the development of age-related cataract, and augmentation of the antioxidant defence systems may be of benefit to prevent or delay cataractogenesis. PMID:23781296

  18. Serum Antioxidative Enzymes Levels and Oxidative Stress Products in Age-Related Cataract Patients

    Directory of Open Access Journals (Sweden)

    Dong Chang

    2013-01-01

    Full Text Available Purpose. To investigate the activity of antioxidative enzymes and the products of oxidative stress in patients with age-related cataracts and compare the findings with those in healthy control subjects. Method. Sixty patients with age-related cataract and sixty healthy controls of matched age and gender were included in this study. Serum samples were obtained to detect the antioxidative enzymes of superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GSH-Px, and oxidation degradation products of malondialdehyde (MDA, 4-hydroxynonenal (4-HNE, conjugated diene (CD, advanced oxidation protein products (AOPP, protein carbonyl (PC, and 8-hydroxydeoxyguanosine (8-OHdG. Results. Serum SOD, GSH-Px, and CAT activities in cataract group were significantly decreased as compared to the control subjects (P<0.05. The levels of MDA, 4-HNE, and CD in cataract patients were significantly higher than those in the control subjects (P<0.05, P<0.01. Cataract patients had higher levels of 8-OHdG, AOPP, and PC with respect to the comparative group of normal subjects (P<0.01. And there was no statistical significance in concentration of antioxidative enzymes and oxidative stress products in patients with different subtype cataract. Conclusions. Oxidative stress is an important risk factor in the development of age-related cataract, and augmentation of the antioxidant defence systems may be of benefit to prevent or delay cataractogenesis.

  19. Molecular and Catalytic Properties of the Aldehyde Dehydrogenase of Gluconacetobacter diazotrophicus, a Quinoheme Protein Containing Pyrroloquinoline Quinone, Cytochrome b, and Cytochrome c▿

    Science.gov (United States)

    Gómez-Manzo, S.; Chavez-Pacheco, J. L.; Contreras-Zentella, M.; Sosa-Torres, M. E.; Arreguín-Espinosa, R.; Pérez de la Mora, M.; Membrillo-Hernández, J.; Escamilla, J. E.

    2010-01-01

    Several aldehyde dehydrogenase (ALDH) complexes have been purified from the membranes of acetic acid bacteria. The enzyme structures and the chemical nature of the prosthetic groups associated with these enzymes remain a matter of debate. We report here on the molecular and catalytic properties of the membrane-bound ALDH complex of the diazotrophic bacterium Gluconacetobacter diazotrophicus. The purified ALDH complex is a heterodimer comprising two subunits of 79.7 and 50 kDa, respectively. Reversed-phase high-pressure liquid chromatography (HPLC) and electron paramagnetic resonance spectroscopy led us to demonstrate, for the first time, the unequivocal presence of a pyrroloquinoline quinone prosthetic group associated with an ALDH complex from acetic acid bacteria. In addition, heme b was detected by UV-visible light (UV-Vis) spectroscopy and confirmed by reversed-phase HPLC. The smaller subunit bears three cytochromes c. Aliphatic aldehydes, but not formaldehyde, were suitable substrates. Using ferricyanide as an electron acceptor, the enzyme showed an optimum pH of 3.5 that shifted to pH 7.0 when phenazine methosulfate plus 2,6-dichlorophenolindophenol were the electron acceptors. Acetaldehyde did not reduce measurable levels of the cytochrome b and c centers; however, the dithionite-reduced hemes were conveniently oxidized by ubiquinone-1; this finding suggests that cytochrome b and the cytochromes c constitute an intramolecular redox sequence that delivers electrons to the membrane ubiquinone. PMID:20802042

  20. Development of an LC-MS/MS analytical method for the simultaneous measurement of aldehydes from polyunsaturated fatty acids degradation in animal feed.

    Science.gov (United States)

    Douny, Caroline; Bayram, Pinar; Brose, François; Degand, Guy; Scippo, Marie-Louise

    2016-05-01

    Knowing that polyunsaturated fatty acids can lead to the formation of potentially toxic aldehydes as secondary oxidation products, an analytical method using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) detection was developed to measure the concentration of eight aldehydes in animal feed: malondialdehyde (MDA), 4-hydroxy-2-nonenal (4-HNE), 4-hydroxy-2-hexenal (4-HHE), crotonaldehyde (CRT), benzaldehyde (BNZ), hexanal (HXL), 2,4-nonadienal, and 2,4-decadienal. The developed method was validated according to the criteria and procedure described in international standards. The evaluated parameters were specificity/selectivity, recovery, precision, accuracy, uncertainty, limits of detection and quantification, using the concept of accuracy profiles. These parameters were determined during experiments conducted over three different days with ground Kellogg's® Corn Flakes® cereals as model matrix for animal feed and spiked at different levels of concentration. Malondialdehyde, 4-HHE, 4-HNE, crotonaldehyde, benzaldehyde, and hexanal can be analyzed in the same run in animal feed with a very good accuracy, with recovery rates ranging from 86 to 109% for a working range going from 0.16 to 12.50 mg/kg. The analysis of 2,4-nonadienal and 2,4-decadienal can also be performed but in a limited range of concentration and with a limited degree of accuracy. Their recovery rates ranged between 54 and 114% and coefficient of variation for the intermediate precision between 11 and 25% for these two compounds. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Oxidative stress, melatonin level, and sleep insufficiency among electronic equipment repairers

    Directory of Open Access Journals (Sweden)

    El-Helaly Mohamed

    2010-01-01

    Full Text Available Background: Exposure to extremely low frequency electromagnetic field (ELF-EMF, especially among electronic equipment repairers may induce oxidative stress and affect sleep quality. Aims: This study was carried out to (a investigate the effect of exposure to ELF-EMF on the malondialdehyde (MDA levels among electronic equipment repairers as an indicator of oxidative stress; and melatonin hormone levels; and (b to study the prevalence of sleep insufficiency among electronic equipment repairers exposed to ELF-EMF. Materials and Methods: A cross-sectional study was carried out on 50 electronic equipment repairers at high risk of exposure to ELF-EMF, and a matched control group at lower risk of exposure to ELF-EMF. All the participants completed a self-administered questionnaire about medical and occupational histories; and sleep sufficiency. The plasma melatonin and MDA levels of the study subjects were assessed. Results: The mean level of serum melatonin in the electronic equipment repairers was lower than that of the controls (P < 0.01. Moreover, serum MDA mean level of the electronic equipment repairers was higher than that of the controls (P < 0.01. Sleep insufficiency was more frequent among electronic equipment repairers (18.00% in comparison with the controls (8.70% (P > 0.05. Conclusion: The electronic equipment repairers, exposed to ELF-EMF, are at a risk of oxidative stress and sleep insufficiency, which could be explained by lower plasma melatonin levels and higher MDA levels. Health education about the hazards of ELF-EMF, shortening of exposure time per day, and taking antioxidant vitamins should be done to ameliorate the oxidative effect of EMF on those workers.

  2. Toxicity of algal-derived aldehydes to two invertebrate species: Do heavy metal pollutants have a synergistic effect?

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Rebecca L. [School of Marine Science and Technology, University of Newcastle upon Tyne, Ridley Building, Claremont Road, Newcastle upon Tyne NE1 7RU (United Kingdom)]. E-mail: r.l.taylor@ncl.ac.uk; Caldwell, Gary S. [School of Marine Science and Technology, University of Newcastle upon Tyne, Ridley Building, Claremont Road, Newcastle upon Tyne NE1 7RU (United Kingdom); Bentley, Matthew G. [School of Marine Science and Technology, University of Newcastle upon Tyne, Ridley Building, Claremont Road, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2005-08-15

    The recent discovery of the production of anti-proliferative aldehydes in a variety of microalgal species has lead to considerable investigation into the effects of these toxins on aquatic invertebrates. Studies have, however, rarely considered the impact pollutants may have on grazer responses to algal toxins. In this study, the acute toxicities of five aldehydes to the rotifer Brachionus plicatilis and nauplii of the brine shrimp Artemia salina are examined using immersion assays. In addition, the effect of a representative of these aldehydes in the presence of sub-lethal levels of heavy metals was examined. B. plicatilis generally showed greater sensitivity to the aldehydes than A. salina. The polyunsaturated 2-trans,4-trans-decadienal was the most toxic to both species having 24 h LD{sub 50} values of 7 and 20 {mu}M for B. plicatilis and A. salina, respectively. The remaining aldehydes had different orders of toxicity for the two species with a stronger relationship observed between mortality and aldehyde carbon-chain length for A. salina whereas B. plicatilis mortality showed a stronger dependence on the presence of carbon-carbon double bonds in the aldehydes. The presence of 1 {mu}M of copper sulphate in solutions of decadienal resulted in the reduction of the 24 h LD{sub 50} of decadienal by approximately a third for both species. 1 {mu}M of copper chloride in solutions of decadienal reduced the 24 h LD{sub 50} of decadienal to A. salina nauplii by approximately 11% and 1 {mu}M zinc sulphate caused a reduction of only 3%. Pre-exposure of the organisms to 1 {mu}M copper sulphate had no significant impact on their subsequent mortality in decadienal. The ecological implications and the possible mechanisms for the action of copper sulphate on the response of organisms to decadienal are discussed.

  3. Increased levels of thioredoxin in patients with abdominal aortic aneurysms (AAAs). A potential link of oxidative stress with AAA evolution

    DEFF Research Database (Denmark)

    Martinez-Pinna, R; Lindholt, Jes S.; Blanco-Colio, L M;

    2010-01-01

    Oxidative stress is a main mechanism involved in vascular pathologies. Increased thioredoxin (TRX) levels have been observed in several oxidative stress-associated cardiovascular diseases. We aim to test the potential role of TRX as a biomarker of oxidative stress in abdominal aortic aneurysm (AAA)....

  4. Endothelial nitric oxide synthase gene haplotypes and circulating nitric oxide levels significantly associate with risk of essential hypertension.

    Science.gov (United States)

    Nejatizadeh, Azim; Kumar, Rahul; Stobdan, Tsering; Goyal, A K; Sikdar, Sunandan; Gupta, Mohit; Javed, Saleem; Pasha, M A Qadar

    2008-06-01

    Nitric oxide (NO), a potent vasodilator, plays a pivotal role in blood pressure regulation. Endothelial NO synthase gene (NOS3) polymorphisms influence NO levels. Here, we investigated the role of the -922A/G, -786T/C, 4b/4a, and 894G/T polymorphisms of the NOS3 and NO(x) levels in 800 consecutive unrelated subjects comprising 455 patients of essential hypertension and 345 controls. The polymorphisms were investigated independently and as haplotypes. Plasma NO(x) levels (nitrate and nitrite) were estimated by the Griess method. Genotype frequencies for the -786T/C, 4b/4a, and 894G/T polymorphisms differed significantly (Phypertension (OR=2.0, OR=3.8, OR=1.6, respectively). The 4-locus haplotypes ATaG (H1), ATaT (H2), and GCaG (H3) were significantly associated with essential hypertension and served as susceptible haplotypes (Phypertension and served as protective haplotypes (Ppolymorphisms showed marginal association with NO(x) level; however, the susceptible haplotype H2 associated significantly with lower NO(x) levels in patients (Ppolymorphisms were identified as the determinants modifying the risk of hypertension. This study identifies the NOS3 variants and haplotypes as genetic risk factors and as useful markers of increased susceptibility to the risk of essential hypertension. PMID:18325347

  5. Relationship Between the Levels of Oxidative Stress in Mesenteric and Peripheral Serum and Clinicopathological Variables in Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Sevim Purisa

    2012-06-01

    Full Text Available Objective: To explore the differences existing between the levels of oxidative stress in peripheral and mesenteric serum in patients with colorectal cancer. Material and Methods: One hundred fifty patients with colorectal cancer who underwent surgery between May 2005 and March 2010 were prospectively analyzed. The differences between oxidative stress parameters in their peripheral and mesenteric blood were measured. The associations between peripheral and mesenteric levels and the staging and clinicopathological variables were investigated.Results: Oxidative stress parameters were higher in patients with advanced tumor staging (p<0.01, lymph node invasion (p<0.01, and venous invasion (p<0.01. Differences between oxidative stress parameters in peripheral and mesenteric blood samples were also observed.Conclusions: The mesenteric levels of the oxidative stress markers were higher than the peripheral levels in these colorectal cancer patients. Higher levels of these oxidative stress markers are associated with an advanced state of cancer.

  6. Oxidative stress and decreased thiol level in patients with migraine: cross-sectional study.

    Science.gov (United States)

    Eren, Yasemin; Dirik, Ebru; Neşelioğlu, Salim; Erel, Özcan

    2015-12-01

    Although migraine is a neurological disorder known since long, its physiopathology remains unclear. Recent studies suggest that migraine is associated with oxidative stress; however, they report divergent results. The aim of the present study was to evaluate total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), and serum thiol level in migraine patients with or without aura. The study group consisted of 141 migraine patients. The control group included 70 healthy subjects. TAS, TOS, OSI were evaluated using a method developed by Erel. Serum thiol level was measured using the Hu method. No difference was found in TAS, TOS, OSI between the patients and controls. The level of thiol was significantly lower in patients than in controls. Negative correlations were detected between thiol level and Migraine Disability Assessment score in patients. Although TAS, TOS, and OSI were similar to those of the control group, serum thiol level, an important marker of antioxidant capacity, was significantly lower in migraines compared with controls, and caused more serious disability. Novel treatment approaches may be developed based on these data, and compounds containing thiol, such as alpha lipoic acid and N-acetyl cysteine, may be used in prophylaxis.

  7. A wafer-level liquid cavity integrated amperometric gas sensor with ppb-level nitric oxide gas sensitivity

    International Nuclear Information System (INIS)

    A miniaturized amperometric nitric oxide (NO) gas sensor based on wafer-level fabrication of electrodes and a liquid electrolyte chamber is reported in this paper. The sensor is able to detect NO gas concentrations of the order of parts per billion (ppb) levels and has a measured sensitivity of 0.04 nA ppb−1 with a response time of approximately 12 s. A sufficiently high selectivity of the sensor to interfering gases such as carbon monoxide (CO) and to ammonia (NH3) makes it potentially relevant for monitoring of asthma. In addition, the sensor was characterized for electrolyte evaporation which indicated a sensor operation lifetime allowing approximately 200 measurements. (paper)

  8. Correction factors for 13C-labelled substrate oxidation at whole-body and muscle level

    DEFF Research Database (Denmark)

    Van Hall, Gerrit

    1999-01-01

    The oxidation of fatty acids, carbohydrates and amino acids can be measured by quantifying the rate of excretion of labelled CO2 following administration of 14C- or 13C-labelled substrates at whole-body and tissue level. However, there is a theoretical need to correct the oxidation rates...... for the proportion of labelled CO2 that is produced via oxidation but not excreted. Furthermore, depending on the substrate and position of the C label(s), there may also be a need to correct for labelled C from the metabolized substrate that does not appear as CO2, but rather becomes temporarily fixed in other...... metabolites. The bicarbonate correction factor is used to correct for the labelled CO2 not excreted. Recently, an acetate correction factor has been proposed for the simultaneous correction of CO2 not excreted and label fixed in other metabolites via isotopic exchange reactions, mainly in the tricarboxylic...

  9. Membrane of Functionalized Reduced Graphene Oxide Nanoplates with Angstrom-Level Channels

    Science.gov (United States)

    Lee, Byeongho; Li, Kunzhou; Yoon, Hong Sik; Yoon, Jeyong; Mok, Yeongbong; Lee, Yan; Lee, Hong H.; Kim, Yong Hyup

    2016-06-01

    Membranes with atomic level pores or constrictions are valuable for separation and catalysis. We report a graphene-based membrane with an interlayer spacing of 3.7 angstrom (Å). When graphene oxide nanoplates are functionalized and then reduced, the laminated reduced graphene oxide (rGO) nanoplates or functionalized rGO membrane is little affected by an intercalated fluid, and the interlayer spacing of 3.7 Å increases only to 4.4 Å in wetted state, in contrast to the graphene oxide (GO) membrane whose interlayer spacing increases from 9 Å to 13 Å in wetted state. When applied to ion separation, this membrane reduced the permeation rate of small ions such as K+ and Na+ by three orders of magnitude compared to the GO membrane.

  10. Mild and efficient strategy for site-selective aldehyde modification of glycosaminoglycans: tailoring hydrogels with tunable release of growth factor.

    Science.gov (United States)

    Wang, Shujiang; Oommen, Oommen P; Yan, Hongji; Varghese, Oommen P

    2013-07-01

    Aldehydes have been used as an important bioorthogonal chemical reporter for conjugation of large polymers and bioactive substances. However, generating aldehyde functionality on carbohydrate-based biopolymers without changing its native chemical structure has always persisted as a challenging task. The common methods employed to achieve this require harsh reaction conditions, which often compromise the structural integrity and biological function of these sensitive molecules. Here we report a mild and simple method to graft aldehydes groups on glycosaminoglycans (GAGs) in a site-selective manner without compromising the structural integrity of the biopolymer. This regio-selective modification was achieved by conjugating the amino-glycerol moiety on the carboxylate residue of the polymer, which allowed selective cleavage of pendent diol groups without interfering with the C2-C3 diol groups of the native glucopyranose residue. Kinetic evaluation of this reaction demonstrated significant differences in second-order reaction rate for periodate oxidation (by four-orders of magnitude) between the two types of vicinal diols. We employed this chemistry to develop aldehyde modifications of sulfated and nonsulfated GAGs such as hyaluronic acid (HA), heparin (HP), and chondroitin sulfate (CS). We further utilized these aldehyde grafted GAGs to tailor extracellular matrix mimetic injectable hydrogels and evaluated its rheological properties. The composition of the hydrogels was also found to modulate release of therapeutic protein such as FGF-2, demonstrating controlled release (60%) for over 14 days. In short, our result clearly demonstrates a versatile strategy to graft aldehyde groups on sensitive biopolymers under mild conditions that could be applied for various bioconjugation and biomedical applications such as drug delivery and regenerative medicine.

  11. Nitric oxide levels in the anterior chamber of vitrectomized eyes with silicon oil

    Directory of Open Access Journals (Sweden)

    Paulo Escarião

    2013-10-01

    Full Text Available PURPOSE: To investigate the nitric oxide levels in the anterior chamber of eyes who underwent pars plana vitrectomy (PPV with silicone oil. METHODS: Patients who underwent PPV with silicon oil injection, from february 2005 to august 2007, were selected. Nine patients (nine eyes participated in the study (five women and four men. Nitric oxide concentration was quantified after the aspiration of aqueous humor samples during the procedure of silicon oil removal. Data such as: oil emulsification; presence of oil in the anterior chamber; intraocular pressure and time with silicone oil were evaluated. Values of p <0.05 were considered to be statistically significant. RESULTS: A positive correlation between nitric oxide concentration and time with silicon oil in the vitreous cavity (r=0.799 was observed. The nitric oxide concentration was significantly higher (p=0.02 in patients with silicon oil more than 24 months (0.90µmol/ml ± 0.59, n=3 in the vitreous cavity comparing to patients with less than 24 months (0.19µmol/ml ± 0.10, n=6. CONCLUSION: A positive correlation linking silicone oil time in the vitreous cavity with the nitric oxide concentration in the anterior chamber was observed.

  12. Oxidized phosphatidylcholines in membrane-level cellular signaling: from biophysics to physiology and molecular pathology.

    Science.gov (United States)

    Volinsky, Roman; Kinnunen, Paavo K J

    2013-06-01

    The oxidation of lipids has been shown to impact virtually all cellular processes. The paradigm has been that this involvement is due to interference with the functions of membrane-associated proteins. It is only recently that methodological advances in molecular-level detection and identification have begun to provide insights into oxidative lipid modification and its involvement in cell signaling as well as in major diseases and inflammation. Extensive evidence suggests a correlation between lipid peroxidation and degenerative neurological diseases such as Parkinson's and Alzheimer's, as well as type 2 diabetes and cancer. Despite the obvious relevance of understanding the molecular basis of the above ailments, the exact modes of action of oxidized lipids have remained elusive. In this minireview, we summarize recent findings on the biophysical characteristics of biomembranes following oxidative derivatization of their lipids, and how these altered properties are involved in both physiological processes and major pathological conditions. Lipid-bearing, oxidatively truncated and functionalized acyl chains are known to modify membrane bulk physical properties, such as thermal phase behavior, bilayer thickness, hydration and polarity profiles, as manifest in the altered structural dynamics of lipid bilayers, leading to augmented membrane permeability, fast lipid transbilayer diffusion (flip-flop), loss of lipid asymmetry (scrambling) and phase segregation (the formation of 'rafts'). These changes, together with the generated reactive lipid derivatives, can be further expected to interfere with lipid-protein interactions, influencing metabolic pathways, causing inflammation, the execution phase in apoptosis and initiating pathological processes. PMID:23506295

  13. Coenzyme Q10 in human blood: native levels and determinants of oxidation during processing and storage.

    Science.gov (United States)

    Franke, Adrian A; Morrison, Cynthia M; Bakke, Jesse L; Custer, Laurie J; Li, Xingnan; Cooney, Robert V

    2010-06-15

    Coenzyme Q10 (Q10) is present in the circulation mainly in its reduced form (ubiquinol-10; UL10), but oxidizes quickly ex vivo to ubiquinone-10 (UN10). Therefore, native UL10:UN10 ratios, used as markers of redox status and disease risk, are difficult to measure. We established an RP-(U)HPLC method with coulometric detection to measure natively circulating UL10 and UN10 concentrations by adding a ubiquinol/ubiquinone mixture as an internal standard immediately after plasma preparation. This allowed adjustment for unavoidable artificial UL10 oxidation as well as for total losses (or gains) of analytes during sample storage, processing, and analysis because the internal standards exactly paralleled the chemical behavior of Q10. This technique applied to blood (n = 13) revealed Q10 levels of 680-3300 nM with a mean UL10:UN10 ratio of 95:5, which was inversely associated with total Q10 (r=-0.69; p=0.004). The oxidation of UL10 to UN10 was equimolar, increased by O(2), and decreased by lower temperatures or various degassing methods. Although UL10 was stable in blood or when pure in organic solvents at 22 degrees C, its oxidation was catalyzed dose dependently by alpha-tocopherol and butylated hydroxytoluene, particularly when present in combination. Key structural features for the catalytic pro-oxidant properties of phenolic antioxidants included two substituents vicinal to the phenolic hydroxyl group. PMID:20226852

  14. Levels of oxidative stress parameters and the protective effects of melatonin in psychosis model rat testis

    Institute of Scientific and Technical Information of China (English)

    Bekir S.Parlaktas; Birsen Ozyurt; Huseyin Ozyurt; Ayten T.Tunc; Ali Akbas

    2008-01-01

    Aim: To evaluate the effects of melatonin on antioxidant enzyme levels and histopathologic changes in dizocilpine (MK-801)-induced psychosis model rat testis. Methods: A total of 24 adult male Wistar-Albino rats were divided into three groups with 8 in each. Group Ⅰ was used as control. Rats in Group Ⅱ were injected with MK-801 (0.5 mg/kg body weight i.p. for 5 days). In addition to MK-801, melatonin (50 mg/kg body weight i.p. once a day for 5 days) was injected into the rats in Group Ⅲ. The testes were harvested bilaterally for biochemical and histopathological examinations. Antioxidant enzyme activities, malondialdehyde, protein carbonyl and nitric oxide (NO) levels in tes-ticular tissues were analyzed using spectrophotometric analysis methods. Histopathological examinations of the testes were also performed. Results: MK-801 induced testicular damage, which resulted in significant oxidative stress (OS) by increasing the levels of antioxidant enzymes. The malondialdehyde, protein carbonyl and NO levels were increased in testicular tissues of rats. Treatment with melatonin led to significant decrease in oxidative injury.Administration of melatonin also reduced the detrimental histopathologic effects caused by MK-801. Conclusion:The results of the present study showed that MK-801 cause OS in testicular tissues of rats and treatment with melatonin can reduce the harmful effects of MK-801.

  15. Relationship of Serum Trimethylamine N-Oxide (TMAO) Levels with early Atherosclerosis in Humans.

    Science.gov (United States)

    Randrianarisoa, Elko; Lehn-Stefan, Angela; Wang, Xiaolin; Hoene, Miriam; Peter, Andreas; Heinzmann, Silke S; Zhao, Xinjie; Königsrainer, Ingmar; Königsrainer, Alfred; Balletshofer, Bernd; Machann, Jürgen; Schick, Fritz; Fritsche, Andreas; Häring, Hans-Ulrich; Xu, Guowang; Lehmann, Rainer; Stefan, Norbert

    2016-01-01

    Circulating trimethylamine N-Oxide (TMAO) levels predict cardiovascular disease (CVD), possibly by impacting on cholesterol metabolism and oxidative stress. Because hepatic TMAO production is regulated by insulin signalling and it is unclear whether and to what extent circulating TMAO levels associate with CVD risk, independently of insulin resistance and its important determinants fatty liver and visceral obesity, we have now addressed this question in 220 subjects who participated in the Tübingen Lifestyle Intervention Program. Visceral fat mass (r = 0.40, p insulin sensitivity associated negatively (r = -0.18, p = 0.009) with carotid intima-media thickness (cIMT). Higher TMAO levels (std.-Beta 0.11, p = 0.03) predicted increased cIMT, independently of age, sex and visceral fat mass. While during the lifestyle intervention most cardiovascular risk parameters improved, mean TMAO levels did not change (p = 0.18). However, cIMT decreased significantly (p = 0.0056) only in subjects in the tertile with the largest decrease of TMAO levels (>20%). We provide novel information that increased serum TMAO levels associate with increased cIMT, independently of established cardiovascular risk markers, including insulin resistance, visceral obesity and fatty liver. Furthermore, the decrease of cIMT during a lifestyle intervention may be related to the decrease of TMAO levels. PMID:27228955

  16. Level of nitric oxide in hypertensive patients scheduled on general anaesthesia.

    Science.gov (United States)

    Shirgoska, B; Trajkovska, T; Soljakova, M; Simjanovska, L; Isijanovska, R; Netkovski, J; Efremov, G D

    2005-08-01

    In this prospective study we have analysed the level of nitric oxide in hypertensive patients scheduled for general anaesthesia. In the study were included thirty-four patients with chronicle inflammatory disease of the middle ear who have undergone surgical treatment at the Clinic for Ear, Nose and Throat Surgery. The aim of our study was to determine the plasma level of nitric oxide (NO) and its effects on the circulatory system in hypertensive patients during the general anaesthesia maintained with inhalation of oxygen and nitrous oxide (O2/N2O) mixture. Patients were divided in two groups. During the maintenance of general anaesthesia the patients from the first group were ventilated with O2/N2O, while patients from the second group were ventilated with oxygen and air (O2/air) mixture. The other principles during the general anaesthesia were equal for both groups. For determination of the NO plasma levels we have used the enzymatic method according to Conrad et al., 1993. Our results showed that there is a statistically significant difference of NO plasma level between the two groups. The level of NO was higher in the first group (ventilated with O2/N2O) compared to the second group (ventilated with O/air). The mean arterial pressure and systemic vascular resistance were significantly decreased in the first group, as well. Our results suggest that nitrous oxide (N2O) most probably plays the role of NO donor in hypertensive patients during the maintenance of the general anaesthesia with N2O/O2 mixture. PMID:16118611

  17. An integrated QSAR-PBK/D modelling approach for predicting detoxification and DNA adduct formation of 18 acyclic food-borne α,β-unsaturated aldehydes

    International Nuclear Information System (INIS)

    Acyclic α,β-unsaturated aldehydes present in food raise a concern because the α,β-unsaturated aldehyde moiety is considered a structural alert for genotoxicity. However, controversy remains on whether in vivo at realistic dietary exposure DNA adduct formation is significant. The aim of the present study was to develop physiologically based kinetic/dynamic (PBK/D) models to examine dose-dependent detoxification and DNA adduct formation of a group of 18 food-borne acyclic α,β-unsaturated aldehydes without 2- or 3-alkylation, and with no more than one conjugated double bond. Parameters for the PBK/D models were obtained using quantitative structure–activity relationships (QSARs) defined with a training set of six selected aldehydes. Using the QSARs, PBK/D models for the other 12 aldehydes were defined. Results revealed that DNA adduct formation in the liver increases with decreasing bulkiness of the molecule especially due to less efficient detoxification. 2-Propenal (acrolein) was identified to induce the highest DNA adduct levels. At realistic dietary intake, the predicted DNA adduct levels for all aldehydes were two orders of magnitude lower than endogenous background levels observed in disease free human liver, suggesting that for all 18 aldehydes DNA adduct formation is negligible at the relevant levels of dietary intake. The present study provides a proof of principle for the use of QSAR-based PBK/D modelling to facilitate group evaluations and read-across in risk assessment. - Highlights: • Physiologically based in silico models were made for 18 α,β-unsaturated aldehydes. • Kinetic parameters were determined by in vitro incubations and a QSAR approach. • DNA adduct formation was negligible at levels relevant for dietary intake. • The use of QSAR-based PBK/D modelling facilitates group evaluations and read-across

  18. An integrated QSAR-PBK/D modelling approach for predicting detoxification and DNA adduct formation of 18 acyclic food-borne α,β-unsaturated aldehydes

    Energy Technology Data Exchange (ETDEWEB)

    Kiwamoto, R., E-mail: reiko.kiwamoto@wur.nl; Spenkelink, A.; Rietjens, I.M.C.M.; Punt, A.

    2015-01-01

    Acyclic α,β-unsaturated aldehydes present in food raise a concern because the α,β-unsaturated aldehyde moiety is considered a structural alert for genotoxicity. However, controversy remains on whether in vivo at realistic dietary exposure DNA adduct formation is significant. The aim of the present study was to develop physiologically based kinetic/dynamic (PBK/D) models to examine dose-dependent detoxification and DNA adduct formation of a group of 18 food-borne acyclic α,β-unsaturated aldehydes without 2- or 3-alkylation, and with no more than one conjugated double bond. Parameters for the PBK/D models were obtained using quantitative structure–activity relationships (QSARs) defined with a training set of six selected aldehydes. Using the QSARs, PBK/D models for the other 12 aldehydes were defined. Results revealed that DNA adduct formation in the liver increases with decreasing bulkiness of the molecule especially due to less efficient detoxification. 2-Propenal (acrolein) was identified to induce the highest DNA adduct levels. At realistic dietary intake, the predicted DNA adduct levels for all aldehydes were two orders of magnitude lower than endogenous background levels observed in disease free human liver, suggesting that for all 18 aldehydes DNA adduct formation is negligible at the relevant levels of dietary intake. The present study provides a proof of principle for the use of QSAR-based PBK/D modelling to facilitate group evaluations and read-across in risk assessment. - Highlights: • Physiologically based in silico models were made for 18 α,β-unsaturated aldehydes. • Kinetic parameters were determined by in vitro incubations and a QSAR approach. • DNA adduct formation was negligible at levels relevant for dietary intake. • The use of QSAR-based PBK/D modelling facilitates group evaluations and read-across.

  19. The Genetics of Alcohol Metabolism: Role of Alcohol Dehydrogenase and Aldehyde Dehydrogenase Variants

    OpenAIRE

    Edenberg, Howard J

    2007-01-01

    The primary enzymes involved in alcohol metabolism are alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). Both enzymes occur in several forms that are encoded by different genes; moreover, there are variants (i.e., alleles) of some of these genes that encode enzymes with different characteristics and which have different ethnic distributions. Which ADH or ALDH alleles a person carries influence his or her level of alcohol consumption and risk of alcoholism. Researchers to date pri...

  20. Airborne aldehydes in cabin-air of commercial aircraft: Measurement by HPLC with UV absorbance detection of 2,4-dinitrophenylhydrazones.

    Science.gov (United States)

    Rosenberger, Wolfgang; Beckmann, Bibiana; Wrbitzky, Renate

    2016-04-15

    This paper presents the strategy and results of in-flight measurements of airborne aldehydes during normal operation and reported "smell events" on commercial aircraft. The aldehyde-measurement is a part of a large-scale study on cabin-air quality. The aims of this study were to describe cabin-air quality in general and to detect chemical abnormalities during the so-called "smell-events". Adsorption and derivatization of airborne aldehydes on 2,4-dinitrophenylhydrazine coated silica gel (DNPH-cartridge) was applied using tailor-made sampling kits. Samples were collected with battery supplied personal air sampling pumps during different flight phases. Furthermore, the influence of ozone was investigated by simultaneous sampling with and without ozone absorption unit (ozone converter) assembled to the DNPH-cartridges and found to be negligible. The method was validated for 14 aldehydes and found to be precise (RSD, 5.5-10.6%) and accurate (recovery, 98-103 %), with LOD levels being 0.3-0.6 μg/m(3). According to occupational exposure limits (OEL) or indoor air guidelines no unusual or noticeable aldehyde pollution was observed. In total, 353 aldehyde samples were taken from two types of aircraft. Formaldehyde (overall average 5.7 μg/m(3), overall median 4.9 μg/m(3), range 0.4-44 μg/m(3)), acetaldehyde (overall average 6.5 μg/m(3), overall median 4.6, range 0.3-90 μg/m(3)) and mostly very low concentrations of other aldehydes were measured on 108 flights. Simultaneous adsorption and derivatization of airborne aldehydes on DNPH-cartridges to the Schiff bases and their HPLC analysis with UV absorbance detection is a useful method to measure aldehydes in cabin-air of commercial aircraft. PMID:26376451

  1. Airborne aldehydes in cabin-air of commercial aircraft: Measurement by HPLC with UV absorbance detection of 2,4-dinitrophenylhydrazones.

    Science.gov (United States)

    Rosenberger, Wolfgang; Beckmann, Bibiana; Wrbitzky, Renate

    2016-04-15

    This paper presents the strategy and results of in-flight measurements of airborne aldehydes during normal operation and reported "smell events" on commercial aircraft. The aldehyde-measurement is a part of a large-scale study on cabin-air quality. The aims of this study were to describe cabin-air quality in general and to detect chemical abnormalities during the so-called "smell-events". Adsorption and derivatization of airborne aldehydes on 2,4-dinitrophenylhydrazine coated silica gel (DNPH-cartridge) was applied using tailor-made sampling kits. Samples were collected with battery supplied personal air sampling pumps during different flight phases. Furthermore, the influence of ozone was investigated by simultaneous sampling with and without ozone absorption unit (ozone converter) assembled to the DNPH-cartridges and found to be negligible. The method was validated for 14 aldehydes and found to be precise (RSD, 5.5-10.6%) and accurate (recovery, 98-103 %), with LOD levels being 0.3-0.6 μg/m(3). According to occupational exposure limits (OEL) or indoor air guidelines no unusual or noticeable aldehyde pollution was observed. In total, 353 aldehyde samples were taken from two types of aircraft. Formaldehyde (overall average 5.7 μg/m(3), overall median 4.9 μg/m(3), range 0.4-44 μg/m(3)), acetaldehyde (overall average 6.5 μg/m(3), overall median 4.6, range 0.3-90 μg/m(3)) and mostly very low concentrations of other aldehydes were measured on 108 flights. Simultaneous adsorption and derivatization of airborne aldehydes on DNPH-cartridges to the Schiff bases and their HPLC analysis with UV absorbance detection is a useful method to measure aldehydes in cabin-air of commercial aircraft.

  2. Nanoplasmonic Photoluminescence Spectroscopy at Single-Particle Level: Sensing for Ethanol Oxidation.

    Science.gov (United States)

    Zheng, Zhaoke; Majima, Tetsuro

    2016-02-18

    Surface plasmon resonances of metal nanoparticles have shown significant promise for the use of solar energy to drive catalytic chemical reactions. More importantly, understanding and monitoring such catalytic reactions at single-nanoparticle level is crucial for the study of local reaction processes. Herein, using plasmonic photoluminescence (PL) spectroscopy, we describe a novel sensing method for catalytic ethanol oxidation reactions at the single-nanoparticle level. The Au nanorod monitors the interfacial interaction with ethanol during the catalytic reaction through the PL intensity changes in the single-particle PL spectra. The analysis of energy relaxation of excited electron-hole pairs indicates the relationship between the PL quenching and ethanol oxidation reaction on the single Au nanorod.

  3. Molecular Structure and Reactivity in the Pyrolysis of Aldehydes

    Science.gov (United States)

    Sias, Eric; Cole, Sarah; Sowards, John; Warner, Brian; Wright, Emily; McCunn, Laura R.

    2016-06-01

    The effect of alkyl chain structure on pyrolysis mechanisms has been investigated in a series of aldehydes. Isovaleraldehyde, CH_3CH(CH_3)CH_2CHO, and pivaldehyde, (CH_3)_3CCHO, were subject to thermal decomposition in a resistively heated SiC tubular reactor at 800-1200 °C. Matrix-isolation FTIR spectroscopy was used to identify pyrolysis products. Carbon monoxide and isobutene were major products from each of the aldehydes, which is consistent with what is known from previous studies of unbranched alkyl-chain aldehydes. Other products observed include vinyl alcohol, propene, acetylene, and ethylene, revealing complexities to be considered in the pyrolysis of large, branched-chain aldehydes.

  4. Serum Levels of Stress Hormones and Oxidative Stress Biomarkers Differ according to Sasang Constitutional Type

    Directory of Open Access Journals (Sweden)

    Hyeong Geug Kim

    2015-01-01

    Full Text Available Objectives. This study investigated whether Sasang constitutional type is associated with differences in the serum levels of stress hormones and oxidative stress. Methods. A total of 236 participants (77 males and 159 females were enrolled. The serum levels of cortisol, adrenaline, reactive oxygen species (ROS, and malondialdehyde (MDA were analyzed. Results. The distribution of Sasang constitutional types was as follows: Taeumin, 35.6%; Soumin, 33.0%; and Soyangin, 31.4%. The serum cortisol levels of Taeumin were significantly lower than Soumin (p<0.1 in both sexes and Soyangin (p<0.05 in males and p<0.1 in females. The adrenaline levels were also significantly lower in Taeumin than in Soumin (p<0.05 in males and p<0.1 in females and Soyangin (p<0.1 in males. Serum ROS levels were significantly higher in Soyangin than in Taeumin and Soumin (p<0.05 in males, whereas MDA levels were significantly lower in Taeumin compared with Soumin and Soyangin (p<0.05 in males and p<0.1 in females. Conclusion. Taeumin type may tolerate psychological or oxidative stress better than other types, which suggests a biological mechanism to explain the different pathophysiological features of Sasang constitutional types.

  5. Effects of composite restorations on nitric oxide and uric acid levels in saliva

    OpenAIRE

    Nilgun Akgul; Pinar Gul; Hamit Hakan Alp; Ahmet Kiziltunc

    2015-01-01

    Background and Aims: Dental materials that are used in dentistry should be harmless to oral tissues, and should, therefore, not contain any leachable toxic and diffusible substances capable of causing side effects. This study was intended to investigate the effects on salivary nitric oxide (NO) and uric acid (UA) levels after application of dental composite filling materials to healthy volunteers. Materials and Methods: A total of 52 individuals (32 female and 20 male) participated in the stu...

  6. Amine-functionalized porous silicas as adsorbents for aldehyde abatement.

    Science.gov (United States)

    Nomura, Akihiro; Jones, Christopher W

    2013-06-26

    A series of aminopropyl-functionalized silicas containing of primary, secondary, or tertiary amines is fabricated via silane-grafting on mesoporous SBA-15 silica and the utility of each material in the adsorption of volatile aldehydes from air is systematically assessed. A particular emphasis is placed on low-molecular-weight aldehydes such as formaldehyde and acetaldehyde, which are highly problematic volatile organic compound (VOC) pollutants. The adsorption tests demonstrate that the aminosilica materials with primary amines most effectively adsorbed formaldehyde with an adsorption capacity of 1.4 mmolHCHO g(-1), whereas the aminosilica containing secondary amines showed lower adsorption capacity (0.80 mmolHCHO g(-1)) and the aminosilica containing tertiary amines adsorbed a negligible amount of formaldehyde. The primary amine containing silica also successfully abated higher aldehyde VOC pollutants, including acetaldehyde, hexanal, and benzaldehyde, by effectively adsorbing them. The adsorption mechanism is investigated by (13)C CP MAS solid-state NMR and FT-Raman spectroscopy, and it is demonstrated that the aldehydes are chemically attached to the surface of aminosilica in the form of imines and hemiaminals. The high aldehyde adsorption capacities of the primary aminosilicas in this study demonstrate the utility of amine-functionalized silica materials for reduction of gaseous aldehydes.

  7. Cytokine profile and nitric oxide levels in sera from patients with brucellosis

    OpenAIRE

    Refik M.; Mehmet N.; Durmaz R.; Ersoy Y.

    2004-01-01

    The aims of this study were to investigate the serum levels of some cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin 1ß (IL-1ß), IL-2R, IL-6, and IL-8] and nitric oxide (NO) levels in patients with untreated brucellosis and to test the correlation of these parameters with each other. The study was conducted on 67 subjects, 37 patients with brucellosis and 30 healthy individuals with no history of Brucella infection. Brucellosis was identified by a positive blood culture and/or ...

  8. Photochemical modelling of photo-oxidant levels over the Swiss plateau and emission reduction scenarios

    International Nuclear Information System (INIS)

    During summertime high pressure conditions, high photo-oxidant (O3, H2O2, PAN and others) levels are frequently observed in the planetary boundary layer in central Europe. It is well known that close to the earth's surface ozone is formed by complex reactions involving VOC, NOx, and sunlight. Substantial reductions of both precursors are needed to reduce photo-oxidant levels. In this context the reductions of the abundance of the precursors and the variation of their ratios is of great importance. Here we report model calculations from the Harwell Photochemical Trajectory Model of the levels of O3, H2O2 and PAN along a trajectory over the Swiss Plateau from Lake Constance to Lake Geneva. These calculations are in satisfactory agreement with measurements made during the intensive observation period of the research program POLLUMET (Pollution and Meteorology in Switzerland). Sensitivity calculations of emission reduction scenarios indicate that on the Swiss Plateau the ozone production may be mainly NOx-limited; under conditions where the CO levels are closer to the upper limit within the range (120-600 ppbv). The calculated peak ozone level reduction caused by an exclusive NOx-emission reduction is about three times larger than that caused by an exclusive VOC reduction. The combined reduction of all precursor compounds is the most efficient strategy, although it is only marginally more efficient than the NOx-reduction scenario alone. (author) figs., tabs., 75 refs

  9. Enantiospecific Total Synthesis of the Important Biogenetic Intermediates Along the Ajmaline Pathway, (+)-Polyneuridine and (+)-Polyneuridine Aldehyde, as well as 16-Epi-Vellosimine and Macusine A

    Science.gov (United States)

    Yin, Wenyuan; Kabir, M. Shahjahan; Wang, Zhijian; Rallapalli, Sundari K.; Ma, Jun; Cook, James M.

    2011-01-01

    The first stereospecific synthesis of polyneuridine aldehyde (6), 16-epi-vellosimine (7), (+)-polyneuridine (8), and (+)-macusine A (9) has been accomplished from commercially available D-(+)-tryptophan methyl ester. D-(+)-Tryptophan has served here both as the chiral auxiliary and the starting material for the synthesis of the common intermediate, (+)-vellosimine (13). This alkaloid was available in enantiospecific fashion in seven reaction vessels in 27% overall yield from D-(+)-trytophan methyl ester (14) via a combination of the asymmetric Pictet-Spengler reaction, Dieckmann cyclization, and a stereocontrolled intramolecular enolate-driven palladium-mediated cross-coupling reaction. A new process for this stereocontrolled intramolecular cross-coupling has been developed via a copper-mediated process. The initial results of this investigation indicated that an enolate driven palladium-mediated cross-coupling reaction can be accomplished by a copper-mediated process which is less expensive and much easier to work-up. An enantiospecific total synthesis of (+)-polyneuridine aldehyde (6), which has been proposed as an important biogenetic intermediate in the biosynthesis of quebrachidine (2), was then accomplished in an overall yield of 14.1% in 13 reaction vessels from D-(+)-tryptophan methyl ester (14). Aldehyde 13 was protected as the Na-Boc aldehyde 32 and then converted into the prochiral C (16)-quaternary diol 12 via the practical Tollens’ reaction and deprotection. The DDQ-mediated oxidative cyclization and TFA/Et3SiH reductive cleavage served as protection/deprotection steps to provide a versatile entry into the three alkaloids, polyneuridine aldehyde (6), polyneuridine (8) and macusine A (9) from the quarternary diol 12. The oxidation of the 16-hydroxymethyl group present in the axial position was achieved with the Corey-Kim reagent to provide the desired β-axial aldehydes, polyneuridine aldehyde (6) and 16-epi-vellosimine (7) with 100

  10. Enantiospecific total synthesis of the important biogenetic intermediates along the ajmaline pathway, (+)-polyneuridine and (+)-polyneuridine aldehyde, as well as 16-epivellosimine and macusine A.

    Science.gov (United States)

    Yin, Wenyuan; Kabir, M Shahjahan; Wang, Zhijian; Rallapalli, Sundari K; Ma, Jun; Cook, James M

    2010-05-21

    The first stereospecific synthesis of polyneuridine aldehyde (6), 16-epivellosimine (7), (+)-polyneuridine (8), and (+)-macusine A (9) has been accomplished from commercially available d-(+)-tryptophan methyl ester. d-(+)-Tryptophan has served here both as the chiral auxiliary and the starting material for the synthesis of the common intermediate, (+)-vellosimine (13). This alkaloid was available in enantiospecific fashion in seven reaction vessels in 27% overall yield from d-(+)-trytophan methyl ester (14) via a combination of the asymmetric Pictet-Spengler reaction, Dieckmann cyclization, and a stereocontrolled intramolecular enolate-driven palladium-mediated cross-coupling reaction. A new process for this stereocontrolled intramolecular cross-coupling has been developed via a copper-mediated process. The initial results of this investigation indicated that an enolate-driven palladium-mediated cross-coupling reaction can be accomplished by a copper-mediated process which is less expensive and much easier to work up. An enantiospecific total synthesis of (+)-polyneuridine aldehyde (6), which has been proposed as an important biogenetic intermediate in the biosynthesis of quebrachidine (2), was then accomplished in an overall yield of 14.1% in 13 reaction vessels from d-(+)-tryptophan methyl ester (14). Aldehyde 13 was protected as the N(a)-Boc aldehyde 32 and then converted into the prochiral C(16)-quaternary diol 12 via the practical Tollens' reaction and deprotection. The DDQ-mediated oxidative cyclization and TFA/Et(3)SiH reductive cleavage served as protection/deprotection steps to provide a versatile entry into the three alkaloids polyneuridine aldehyde (6), polyneuridine (8), and macusine A (9) from the quarternary diol 12. The oxidation of the 16-hydroxymethyl group present in the axial position was achieved with the Corey-Kim reagent to provide the desired beta-axial aldehydes, polyneuridine aldehyde (6), and 16-epivellosimine (7) with 100

  11. Blood Levels of Oxidant/Antioxidant Parameters in Rats Infected with Toxoplasma gondii

    Science.gov (United States)

    Shahriari, Ali; Tavalla, Mehdi; Azadmanesh, Somayeh; Hamidinejat, Hossein

    2016-01-01

    Toxoplasmosis is a common parasitic infection in the world. Since increased free radicals and oxidative stress are reported in many parasitic diseases the purpose of the present study was to evaluate the oxidative stress in acute and chronic toxoplasmosis. RH strains of Toxoplasma tachyzoites were used in the present study. Twenty-five female rats were infected with the parasite while 25 other rats were as the control group that received normal saline. Zero-, 5-, 7-, 10-, and 45-day postinfection (DPI) blood samples were taken. Some parameters related to oxidant and antioxidants such as antioxidant enzymes, malondialdehyde, and total antioxidant capacity were measured. On day 7 after infection, GPX activity and GSH level were significantly increased and in the mentioned day the amount of total antioxidant capacity was significantly reduced. In other cases, there were no significant differences between the groups in different days. Overall, based on the results it seems that, on day 7 after infection, in infected rats responses to oxidative stress were triggered and led to decrease of total antioxidant capacity. Furthermore, glutathione was increased to cope with stress. It seems that probably antioxidant defense system entered the infection to the chronic phase and changed the parasites stage. PMID:27746857

  12. Effects of glucocorticoid dexamethasone on serum nitric oxide synthase activity and nitric oxide levels in a rat model of lung disease-induced brain injury

    Institute of Scientific and Technical Information of China (English)

    Huajun Li; Ligang Jiang; Meng Xia; Haiping Li; Fanhua Meng; Wei Li; Lifeng Liu; Zhaohui Wang

    2011-01-01

    In this study, we investigated the effects of dexamethasone, pertussis toxin (a Gi protein inhibitor), and actinomycin (a transcription inhibitor) on serum nitric oxide synthase activity and nitric oxide content in a rat model of lung disease-induced brain injury. High-dose dexamethasone (13 mg/kg) and dexamethasone + actinomycin reduced lung water content, increased serum nitric oxide synthase activity and nitric oxide content, diminished inflammatory cell infiltration in pulmonary alveolar interstitium, attenuated meningeal vascular hyperemia, reduced glial cell infiltration, and decreased cerebral edema. These results demonstrate that high-dose glucocorticoid treatment can reduce the severity of lung disease-induced brain injury by increasing nitric oxide synthase activity and nitric oxide levels.

  13. Levels of lipid peroxidation, nitric oxide, and antioxidant vitamins in plasma of patients with fibromyalgia.

    Science.gov (United States)

    Akkuş, Selami; Naziroğlu, Mustafa; Eriş, Sevilay; Yalman, Kadir; Yilmaz, Nigar; Yener, Mahmut

    2009-06-01

    The etiology of fibromyalgia is not clearly understood. In recent years, a few studies have investigated the possible role of reactive oxygen species (ROS) in the etiology and pathogenesis of fibromyalgia. The aim of this study was to investigate plasma antioxidant vitamins, lipid peroxidation (LP), and nitric oxide (NO) levels in patients with fibromyalgia and controls. The study was performed on the blood plasma of 30 female patients and 30 age-matched controls. After a fast of 12 h, blood samples were taken, and plasma samples were obtained for measurement of vitamins A, C, E, and beta-carotene concentrations and levels of LP and NO. Concentrations of vitamins A (p fibromyalgia than in controls, and LP levels were significantly (p vitamin C and beta-carotene and levels of NO did not change significantly. These results provide some evidence for a potential role of LP and fat-soluble antioxidants in the patients with fibromyalgia. PMID:19319826

  14. Serum Levels of Melatonin and Oxidative Stress Markers and Correlation between Them in Infertile Men

    Directory of Open Access Journals (Sweden)

    Sara Soleimani Rad

    2013-11-01

    Full Text Available Introduction: Infertility is the problem of 15% of young couples in different societies. One of the factors that could affect fertility is oxidative stress. Therefore, the aim of the present study is to investigate the level of Melatonin, a free radical scavenger, and its correlation with oxidative biomarkers in infertile men. Methods:For this purpose, fertile and infertile men in 2 groups, 30 people in each group, were studied. The fertile men were selected from husbands of patients admitted to Alzahra obstetric and gynecology hospital, according to WHO standards. The infertile men were selected from patients referred to infertility ward. Blood sampling from the participants carried out at a specific time, sera collected and the levels of malondialdehyde, total antioxidant capacity and Melatonin were detected in the sera. The data were analyzed using t-test and Sperman's correlation method. Results: Melatonin level in the sera from fertile men were 522 (39.32 ng/L and in infertile men were 511.78 (34.6 ng/L. MDA level in fertile and infertile men were 2.26 (0.34 vs 2.99 (0.44 nmol/ml which was significantly different. The level of TAC in the sera from fertile men were significantly higher than in infertile men. The result obtained for correlation coefficient Spearman's test revealed a significant, strong and direct correlation between Melatonin and TAC and a significant and reverse correlation between melatonin and MDA.Conclusion: It is concluded that melatonin could be involved in infertility. In other word, melatonin treatment and antioxidant-rich nutrition could help fertility by combating oxidative stress.

  15. Aldehyde dehydrogenase-independent bioactivation of nitroglycerin in porcine and bovine blood vessels.

    Science.gov (United States)

    Neubauer, Regina; Wölkart, Gerald; Opelt, Marissa; Schwarzenegger, Christine; Hofinger, Marielies; Neubauer, Andrea; Kollau, Alexander; Schmidt, Kurt; Schrammel, Astrid; Mayer, Bernd

    2015-02-15

    The vascular bioactivation of the antianginal drug nitroglycerin (GTN), yielding 1,2-glycerol dinitrate and nitric oxide or a related activator of soluble guanylate cyclase, is catalyzed by aldehyde dehydrogenase-2 (ALDH2) in rodent and human blood vessels. The essential role of ALDH2 has been confirmed in many studies and is considered as general principle of GTN-induced vasodilation in mammals. However, this view is challenged by an early report showing that diphenyleneiodonium, which we recently characterized as potent ALDH2 inhibitor, has no effect on GTN-induced relaxation of bovine coronary arteries (De La Lande et al., 1996). We investigated this issue and found that inhibition of ALDH2 attenuates GTN-induced coronary vasodilation in isolated perfused rat hearts but has no effect on relaxation to GTN of bovine and porcine coronary arteries. This observation is explained by low levels of ALDH2 protein expression in bovine coronary arteries and several types of porcine blood vessels. ALDH2 mRNA expression and the rates of GTN denitration were similarly low, excluding a significant contribution of ALDH2 to the bioactivation of GTN in these vessels. Attempts to identify the responsible pathway with enzyme inhibitors did not provide conclusive evidence for the involvement of ALDH3A1, cytochrome P450, or GSH-S-transferase. Thus, the present manuscript describes a hitherto unrecognized pathway of GTN bioactivation in bovine and porcine blood vessels. If present in the human vasculature, this pathway might contribute to the therapeutic effects of organic nitrates that are not metabolized by ALDH2.

  16. Key changes in wine aroma active compounds during bottle storage of Spanish red wines under different oxygen levels.

    Science.gov (United States)

    Ferreira, Vicente; Bueno, Mónica; Franco-Luesma, Ernesto; Culleré, Laura; Fernández-Zurbano, Purificación

    2014-10-15

    Samples from 16 Spanish red wines have been stored for 6 months at 25 °C under different levels of oxygen (0-56 mg/L). Amino acids, metals, and phenolic compounds were analyzed and related to the production or depletion of key oxidation- and reduction-related aroma compounds. Oxidation brings about sensory-relevant increases in Strecker aldehydes, 1-octen-3-one, and vanillin. Formation of Strecker aldehydes correlates to the wine content on the corresponding amino acid precursor, Zn, and caffeic acid ethyl ester and negatively to some flavonols and anthocyanin derivatives. Formation of most carbonyls correlates to wine-combined SO2, suggesting that part of the increments are the result of the release of aldehydes forming bisulfite combinations once SO2 is oxidized. Methanethiol (MeSH) and dimethylsulfide (DMS), but not H2S levels, increase during storage. MeSH increments correlate to methionine levels and proanthocyanidins and negatively to resveratrol and aluminum. H2S, MeSH, and DMS levels all decreased with oxidation, and for the latter two, there are important effects of Mn and pH, respectively.

  17. Key changes in wine aroma active compounds during bottle storage of Spanish red wines under different oxygen levels.

    Science.gov (United States)

    Ferreira, Vicente; Bueno, Mónica; Franco-Luesma, Ernesto; Culleré, Laura; Fernández-Zurbano, Purificación

    2014-10-15

    Samples from 16 Spanish red wines have been stored for 6 months at 25 °C under different levels of oxygen (0-56 mg/L). Amino acids, metals, and phenolic compounds were analyzed and related to the production or depletion of key oxidation- and reduction-related aroma compounds. Oxidation brings about sensory-relevant increases in Strecker aldehydes, 1-octen-3-one, and vanillin. Formation of Strecker aldehydes correlates to the wine content on the corresponding amino acid precursor, Zn, and caffeic acid ethyl ester and negatively to some flavonols and anthocyanin derivatives. Formation of most carbonyls correlates to wine-combined SO2, suggesting that part of the increments are the result of the release of aldehydes forming bisulfite combinations once SO2 is oxidized. Methanethiol (MeSH) and dimethylsulfide (DMS), but not H2S levels, increase during storage. MeSH increments correlate to methionine levels and proanthocyanidins and negatively to resveratrol and aluminum. H2S, MeSH, and DMS levels all decreased with oxidation, and for the latter two, there are important effects of Mn and pH, respectively. PMID:25284059

  18. Studies of aldehydes in an atmosphere simulation chamber

    Energy Technology Data Exchange (ETDEWEB)

    Bossmeyer, J.

    2006-05-15

    recommendations at near-ambient concentration levels. However, the measured yields of the product aldehydes in the NO{sub 3} reactions with propanal and butanal disagreed with model calculations. This discrepancy originated from the model assumptions made for the kinetics of peroxyacyl nitrates in the degradation mechanism of the aldehydes. (orig.)

  19. Oxidative Damage in Lymphocytes of Copper Smelter Workers Correlated to Higher Levels of Excreted Arsenic

    Science.gov (United States)

    Escobar, Jorge; Varela-Nallar, Lorena; Coddou, Claudio; Nelson, Pablo; Maisey, Kevin; Valdés, Daniel; Aspee, Alexis; Espinosa, Victoria; Rozas, Carlos; Montoya, Margarita; Mandiola, Cristian; Rodríguez, Felipe E.; Acuña-Castillo, Claudio; Escobar, Alejandro; Fernández, Ricardo; Diaz, Hernán; Sandoval, Mario; Imarai, Mónica; Rios, Miguel

    2010-01-01

    Arsenic has been associated with multiple harmful effects at the cellular level. Indirectly these defects could be related to impairment of the integrity of the immune system, in particular in lymphoid population. To characterize the effect of Arsenic on redox status on this population, copper smelter workers and arsenic unexposed donors were recruited for this study. We analyzed urine samples and lymphocyte enriched fractions from donors to determinate arsenic levels and lymphocyte proliferation. Moreover, we studied the presence of oxidative markers MDA, vitamin E and SOD activity in donor plasma. Here we demonstrated that in human beings exposed to high arsenic concentrations, lymphocyte MDA and arsenic urinary levels showed a positive correlation with SOD activity, and a negative correlation with vitamin E serum levels. Strikingly, lymphocytes from the arsenic exposed population respond to a polyclonal stimulator, phytohemaglutinin, with higher rates of thymidine incorporation than lymphocytes of a control population. As well, similar in vitro responses to arsenic were observed using a T cell line. Our results suggest that chronic human exposure to arsenic induces oxidative damage in lymphocytes and could be considered more relevant than evaluation of T cell surveillance. PMID:21253489

  20. Oxidative Damage in Lymphocytes of Copper Smelter Workers Correlated to Higher Levels of Excreted Arsenic

    Directory of Open Access Journals (Sweden)

    Jorge Escobar

    2010-01-01

    Full Text Available Arsenic has been associated with multiple harmful effects at the cellular level. Indirectly these defects could be related to impairment of the integrity of the immune system, in particular in lymphoid population. To characterize the effect of Arsenic on redox status on this population, copper smelter workers and arsenic unexposed donors were recruited for this study. We analyzed urine samples and lymphocyte enriched fractions from donors to determinate arsenic levels and lymphocyte proliferation. Moreover, we studied the presence of oxidative markers MDA, vitamin E and SOD activity in donor plasma. Here we demonstrated that in human beings exposed to high arsenic concentrations, lymphocyte MDA and arsenic urinary levels showed a positive correlation with SOD activity, and a negative correlation with vitamin E serum levels. Strikingly, lymphocytes from the arsenic exposed population respond to a polyclonal stimulator, phytohemaglutinin, with higher rates of thymidine incorporation than lymphocytes of a control population. As well, similar in vitro responses to arsenic were observed using a T cell line. Our results suggest that chronic human exposure to arsenic induces oxidative damage in lymphocytes and could be considered more relevant than evaluation of T cell surveillance.

  1. Oxidative stress at low levels can induce clustered DNA lesions leading to NHEJ mediated mutations.

    Science.gov (United States)

    Sharma, Vyom; Collins, Leonard B; Chen, Ting-Huei; Herr, Natalie; Takeda, Shunichi; Sun, Wei; Swenberg, James A; Nakamura, Jun

    2016-05-01

    DNA damage and mutations induced by oxidative stress are associated with various different human pathologies including cancer. The facts that most human tumors are characterized by large genome rearrangements and glutathione depletion in mice results in deletions in DNA suggest that reactive oxygen species (ROS) may cause gene and chromosome mutations through DNA double strand breaks (DSBs). However, the generation of DSBs at low levels of ROS is still controversial. In the present study, we show that H2O2 at biologically-relevant levels causes a marked increase in oxidative clustered DNA lesions (OCDLs) with a significant elevation of replication-independent DSBs. Although it is frequently reported that OCDLs are fingerprint of high-energy IR, our results indicate for the first time that H2O2, even at low levels, can also cause OCDLs leading to DSBs specifically in G1 cells. Furthermore, a reverse genetic approach revealed a significant contribution of the non-homologous end joining (NHEJ) pathway in H2O2-induced DNA repair & mutagenesis. This genomic instability induced by low levels of ROS may be involved in spontaneous mutagenesis and the etiology of a wide variety of human diseases like chronic inflammation-related disorders, carcinogenesis, neuro-degeneration and aging. PMID:27015367

  2. Evaluation of Serum Nitric Oxide level in Patients with Oral Lichen Planus

    Directory of Open Access Journals (Sweden)

    Mehdipour M.

    2014-06-01

    Full Text Available Statement of Problem: Oral lichen planus (OLP is a chronic inflammatory oral mucosal disease with indefinite etiology. In recent researches, free radicals have been deliberated as the possible etiology of inflammatory and autoimmune diseases. Purpose: This study aimed to evaluate the stress oxidative status with the nitric oxide (NO index in a sample of Iranian population. Materials and Method: In this descriptive-comparative study; serum NO level was assessed in 20 OLP patients as the case group and 20 healthy individuals as the control group. Collected data were analyzed by adopting two Sample t-test; using SPSS 16 software. Statistical significance level was set at p < 0.05. Results: The mean serum NO levels in OLP patients and healthy controls were 17.1±3.4 ng/ml and 14.5±2.7 ng/ml respectively; which revealed a significant statistic-al difference (p= 0.009. Conclusions: The results of the current study with its limitation may support the premise that higher serum levels of NO in patients with OLP might activate the process of lymphocytes and cellular immunity system; hence, possibly endorsing the effect of serum NO in pathogenesis of lichen planus.

  3. Phobic anxiety and plasma levels of global oxidative stress in women

    Directory of Open Access Journals (Sweden)

    Kaitlin A. Hagan

    2015-03-01

    Full Text Available Background and Objectives: Psychological distress has been hypothesized to be associated with adverse biologic states such as higher oxidative stress and inflammation. Yet, little is known about associations between a common form of distress -phobic anxiety- and global oxidative stress. Thus, we related phobic anxiety to plasma fluorescent oxidation products (FlOPs, a global oxidative stress marker. Methods: We conducted a cross-sectional analysis among 1,325 women (aged 43-70 years from the Nurses' Health Study. Phobic anxiety was measured using the Crown-Crisp Index (CCI. Adjusted least-squares mean log-transformed FlOPs were calculated across phobic categories. Logistic regression models were used to calculate odds ratios (OR comparing the highest CCI category (≥ 6 points vs. lower scores, across FlOPs quartiles. Results: No association was found between phobic anxiety categories and mean FlOP levels in multivariable adjusted linear models. Similarly, in multivariable logistic regression models there were no associations between FlOPs quartiles and likelihood of being in the highest phobic category. Comparing women in the highest vs. lowest FlOPs quartiles: FlOP_360: OR = 0.68 (95% CI: 0.40 - 1.15; FlOP_320: OR = 0.99 (95% CI: 0.61 - 1.61; FlOP_400: OR = 0.92 (95% CI: 0.52, 1.63. Conclusions: No cross-sectional association was found between phobic anxiety and a plasma measure of global oxidative stress in this sample of middle-aged and older women.

  4. Phobic Anxiety and Plasma Levels of Global Oxidative Stress in Women

    Science.gov (United States)

    Hagan, Kaitlin A.; Wu, Tianying; Rimm, Eric B.; Eliassen, A. Heather; Okereke, Olivia I.

    2015-01-01

    Background and Objectives Psychological distress has been hypothesized to be associated with adverse biologic states such as higher oxidative stress and inflammation. Yet, little is known about associations between a common form of distress – phobic anxiety – and global oxidative stress. Thus, we related phobic anxiety to plasma fluorescent oxidation products (FlOPs), a global oxidative stress marker. Methods We conducted a cross-sectional analysis among 1,325 women (aged 43-70 years) from the Nurses’ Health Study. Phobic anxiety was measured using the Crown-Crisp Index (CCI). Adjusted least-squares mean log-transformed FlOPs were calculated across phobic categories. Logistic regression models were used to calculate odds ratios (OR) comparing the highest CCI category (≥6 points) vs. lower scores, across FlOPs quartiles. Results No association was found between phobic anxiety categories and mean FlOP levels in multivariable adjusted linear models. Similarly, in multivariable logistic regression models there were no associations between FlOPs quartiles and likelihood of being in the highest phobic category. Comparing women in the highest vs. lowest FlOPs quartiles: FlOP_360: OR=0.68 (95% CI: 0.40-1.15); FlOP_320: OR=0.99 (95% CI: 0.61-1.61); FlOP_400: OR=0.92 (95% CI: 0.52, 1.63). Conclusions No cross-sectional association was found between phobic anxiety and a plasma measure of global oxidative stress in this sample of middle-aged and older women. PMID:26635425

  5. SPONTANEOUS CATALYTIC WET AIR OXIDATION DURING PRE-TREATMENT OF HIGH-LEVEL RADIOACTIVE WASTE SLUDGE

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, D.; Herman, C.; Pareizs, J.; Bannochie, C.; Best, D.; Bibler, N.; Fellinger, T.

    2009-10-01

    Savannah River Remediation, LLC (SRR) operates the Defense Waste Processing Facility for the U.S. Department of Energy at the Savannah River Site. This facility immobilizes high-level radioactive waste through vitrification following chemical pretreatment. Catalytic destruction of formate and oxalate ions to carbon dioxide has been observed during qualification testing of non-radioactive analog systems. Carbon dioxide production greatly exceeded hydrogen production, indicating the occurrence of a process other than the catalytic decomposition of formic acid. Statistical modeling was used to relate the new reaction chemistry to partial catalytic wet air oxidation of both formate and oxalate ions driven by the low concentrations of palladium, rhodium, and/or ruthenium in the waste. Variations in process conditions led to increases or decreases in the total oxidative destruction, as well as partially shifting the preferred species undergoing destruction from oxalate ion to formate ion.

  6. The Effected Oxide Capacitor in CMOS Structure of Integrated Circuit Level 5 Micrometer Technology

    CERN Document Server

    Rodthong, S

    2009-01-01

    This article is present the effected oxide capacitor in CMOS structure of integrated circuit level 5 micrometer technology. It has designed and basic structure of MOS diode. It establish with aluminum metallization layer by sputtering method, oxide insulator layer mode from silicon dioxide, n+ and p+ semiconductor layer, it has high capacitance concentrate. From the MOS diode structure silicon dioxide thickness 0.5 micrometer, it will get capacitance between aluminum metal layer and p+ semiconductor at 28.62 pF, the capacitance between aluminum metal layer and n+ semiconductor at 29.55 pF. In this article establish second metal layer for measurement density values of first aluminum metal layer with second aluminum metal layer, it has density values at 16 pF.

  7. Factors attributable to the level of exhaled nitric oxide in asthmatic children

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    Banovcin P

    2009-12-01

    Full Text Available Abstract Background Asthma is a heterogeneous disease with variable symptoms especially in children. Exhaled nitric oxide (FeNO has proved to be a marker of inflammation in the airways and has become a substantial part of clinical management of asthmatic children due to its potential to predict possible exacerbation and adjust the dose of inhalant corticosteroids. Objectives We analyzed potential factors that contribute to the variability of nitric oxide in various clinical and laboratory conditions. Materials and methods Study population consisted of 222 asthmatic children and 27 healthy control subjects. All children underwent a panel of tests: fractioned exhaled nitric oxide, exhaled carbon monoxide, asthma control test scoring, blood sampling, skin prick tests, and basic spirometry. Results FeNO and other investigated parameters widely changed according to clinical or laboratory characteristics of the tested children. Asthmatics showed increased levels of FeNO, exhaled carbon monoxide, total serum IgE, and higher eosinophilia. Boys had higher FeNO levels than girls. We found a significant positive correlation between FeNO levels and the percentage of blood eosinophils, %predicted of forced vital capacity, total serum IgE levels, and increasing age. Conclusions Various phenotypes of children's asthma are characterized by specific pattern of the results of clinical and laboratory tests. FeNO correlates with total serum IgE, blood eosinophilia, age, and some spirometric parameters with different strength. Therefore, the coexistence of atopy, concomitant allergic rhinitis/rhinoconjunctivitis, and some other parameters should be considered in critical evaluation of FeNO in the management of asthmatic children.

  8. Elevated nitric oxide and 3',5' cyclic guanosine monophosphate levels in patients with alcoholic cirrhosis

    Institute of Scientific and Technical Information of China (English)

    C(i)ntia Siqueira; Miguel Carneiro de Moura; Ana J(u)lia Pedro; Paula Rocha

    2008-01-01

    AIM: To evaluate whether serum levels of nitric oxide (NO') and plasma levels of cyclic guanosine monophosphate (Cgmp) and total glutathione (GSH) are altered in patients with alcoholic cirrhosis and to examine their correlation with the severity of liver disease.METHODS: Twenty-six patients with alcoholic liver cirrhosis were studied. Serum levels of NO· and plasma levels of cGMP and GSH were measured in 7 patients with compensated alcoholic cirrhosis (Child-Pugh A) and 19 patients with advanced cirrhosis (Child-Pugh B and C).The model for end-stage liver disease (MELD) score was evaluated. Sixteen healthy volunteers served as controls.Liver enzymes and creatinine levels were also tested.RESULTS: NO· and cGMP levels were higher in patients with Child-Pugh B and C cirrhosis than in Child-Pugh A cirrhosis or controls (NO·: 21.70 ± 8.07 vs 11.70 ± 2.74; 21.70 ± 8.07 vs 7.26 ± 2.47 μmol/L, respectively;P < 0.001) and (cGMP: 20.12 ± 6.62 vs 10.14 ± 2.78;20.12 ± 6.62 vs 4.95 ± 1.21 pmol/L, respectively; P <0.001). Total glutathione levels were lower in patients with Child-Pugh B and C cirrhosis than in patients with Child-Pugh A cirrhosis or controls (16.04 ± 6.06 vs 23.01 ± 4.38 or 16.04 ± 6.06 vs 66.57 ± 26.23 μmol/L,respectively; P < 0.001). There was a significant correlation between NO· and cGMP levels in all patients with alcoholic cirrhosis. A significant negative correlation between reduced glutathione/glutathione disulfide and the MELD score was found in all cirrhotic patients. CONCLUSION: Our results suggest a role for oxidative stress in alcoholic liver cirrhosis, which is more significant in decompensated patients with higher levels of NO· and cGMP and lower GSH levels than in compensated and control patients. Altered mediator levels in decompensated patients may influence the hemodynamic changes in and progression of liver disease.

  9. Ambient concentrations of aldehydes in relation to Beijing Olympic air pollution control measures

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    J. C. Gong

    2010-08-01

    Full Text Available Aldehydes are ubiquitous constituents of the atmosphere. Their concentrations are elevated in polluted urban atmospheres. The present study was carried out to characterize three aldehydes of most health concern (formaldehyde, acetaldehyde, and acrolein in a central Beijing site in the summer and early fall of 2008 (from June to October. Measurements were made before, during, and after the Beijing Olympics to examine whether the air pollution control measures implemented to improve Beijing's air quality during the Olympics had any impact on concentrations of the three aldehydes. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.34 ± 15.12 μg/m3, 27.09 ± 15.74 μg/m3 and 2.32 ± 0.95 μg/m3, respectively, for the entire period of measurements, all being the highest among the levels measured in cities around the world in photochemical smog seasons. Among the three measured aldehydes, only acetaldehyde had a substantially reduced mean concentration during the Olympic air pollution control period compared to the pre-Olympic period. Formaldehyde and acrolein followed the changing pattern of temperature and were each significantly correlated with ozone (a secondary product of photochemical reactions. In contrast, acetaldehyde was significantly correlated with several pollutants emitted mainly from local emission sources (e.g., NO2, CO, and PM2.5. These findings suggest that local direct emissions had a larger impact on acetaldehyde than formaldehyde and acrolein.

  10. Enhanced xylene removal by photocatalytic oxidation using fiber-illuminated honeycomb reactor at ppb level

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yi-Ting [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Yu, Yi-Hui [Department of Civil Engineering, National Taiwan University, Taipei 106, Taiwan (China); Nguyen, Van-Huy [Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10617, Taiwan (China); Lu, Kung-Te [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Wu, Jeffrey Chi-Sheng, E-mail: cswu@ntu.edu.tw [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Chang, Luh-Maan [Department of Civil Engineering, National Taiwan University, Taipei 106, Taiwan (China); Kuo, Chi-Wen [Taiwan Semiconductor Manufacturing Company, Hsinchu 30078, Taiwan (China)

    2013-11-15

    Graphical abstract: We have designed a fiber-illuminated honeycomb reactor (FIHR) in which the removal efficiency of m-xylene is significantly enhanced to 96.5% as compared to 22.0% for UV irradiation only. The results indicate that photocatalysts not only play the role to substantially oxidize m-xylene, but also alter the chemical properties of xylene under UV illumination. -- Highlights: • The combination of optical fiber and honeycomb significantly enhanced the performance of VOCs photodegradation. • The removal efficiency of m-xylene is enhanced to 96.5% as compared to 22.0% for UV irradiation alone. • Fiber-illuminated honeycomb reactor is the first step toward an industrial-scale technology on the removal of xylene. -- Abstract: The removal of volatile organic compounds (VOCs) at ppb level is one of the most critical challenges in clean rooms for the semiconductor industry. Photocatalytic oxidation is an innovative and promising technology for ppb-level VOCs degradation. We have designed a fiber-illuminated honeycomb reactor (FIHR) in which the removal efficiency of m-xylene is significantly enhanced to 96.5% as compared to 22.0% for UV irradiation only. The results indicate that photocatalysts not only play the role to substantially oxidize m-xylene, but also alter the chemical properties of xylene under UV illumination. Using the FIHR with Mn-TiO{sub 2} photocatalyst not only increased the m-xylene removal efficiency, but also increased the CO{sub 2} selectivity. Interestingly, Mn-TiO{sub 2} in FIHR also showed a very good reusability, 93% removal efficiency was still achieved in 72-h in reaction. Thus, the FIHR gave very high removal efficiency for xylene at ppb level under room temperature. The FIHR has great potential application in the clean room for the air purification system in the future.

  11. Nitric oxide levels in women with missed and threatened abortion: results of a pilot study.

    Science.gov (United States)

    Paradisi, Roberto; Fabbri, Raffaella; Battaglia, Cesare; Facchinetti, Fabio; Venturoli, Stefano

    2007-09-01

    The aim of this study was to evaluate the systemic production of nitric oxide (NO) in missed and threatened abortion and in nonpregnant and regular pregnant controls with the purpose of defining its role in the mechanisms regulating the first-trimester pregnancy toward either positive or negative evolution. Patients with missed abortion showed serum NO levels clearly decreased compared with nonpregnant patients and patients with regular pregnancy and threatened abortion, supporting a direct functional role of the NO mediator in early embryonic development and confirming its importance in the uterus and cervix during abortion. PMID:17349639

  12. Transparent Conducting Oxides for Photovoltaics: Manipulation of Fermi Level, Work Function and Energy Band Alignment

    Directory of Open Access Journals (Sweden)

    Diana E. Proffit

    2010-11-01

    Full Text Available Doping limits, band gaps, work functions and energy band alignments of undoped and donor-doped transparent conducting oxides Zn0, In2O3, and SnO2 as accessed by X-ray and ultraviolet photoelectron spectroscopy (XPS/UPS are summarized and compared. The presented collection provides an extensive data set of technologically relevant electronic properties of photovoltaic transparent electrode materials and illustrates how these relate to the underlying defect chemistry, the dependence of surface dipoles on crystallographic orientation and/or surface termination, and Fermi level pinning.

  13. The roles of aldehyde dehydrogenases (ALDHs in the PDH bypass of Arabidopsis

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    Lin Ming

    2009-03-01

    Full Text Available Abstract Background Eukaryotic aldehyde dehydrogenases (ALDHs, EC 1.2.1, which oxidize aldehydes into carboxylic acids, have been classified into more than 20 families. In mammals, Family 2 ALDHs detoxify acetaldehyde. It has been hypothesized that plant Family 2 ALDHs oxidize acetaldehyde generated via ethanolic fermentation, producing acetate for acetyl-CoA biosynthesis via acetyl-CoA synthetase (ACS, similar to the yeast pathway termed the "pyruvate dehydrogenase (PDH bypass". Evidence for this pathway in plants has been obtained from pollen. Results To test for the presence of the PDH bypass in the sporophytic tissue of plants, Arabidopsis plants homozygous for mutant alleles of all three Family 2 ALDH genes were fed with 14C-ethanol along with wild type controls. Comparisons of the incorporation rates of 14C-ethanol into fatty acids in mutants and wild type controls provided direct evidence for the presence of the PDH bypass in sporophytic tissue. Among the three Family 2 ALDHs, one of the two mitochondrial ALDHs (ALDH2B4 appears to be the primary contributor to this pathway. Surprisingly, single, double and triple ALDH mutants of Arabidopsis did not exhibit detectable phenotypes, even though a Family 2 ALDH gene is required for normal anther development in maize. Conclusion The PDH bypass is active in sporophytic tissue of plants. Blocking this pathway via triple ALDH mutants does not uncover obvious visible phenotypes.

  14. Estimation and comparison of levels of salivary nitric oxide in patients with oral lichen planus and controls

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    Sapna Panjwani

    2013-01-01

    Full Text Available Background: Normal salivary function is considered to be critical for the maintenance of healthy oral mucosa. Oral fluids provide an easily available, non-invasive medium for the diagnosis of wide range of diseases and clinical situations. The objective of this study was to estimate and compare salivary nitric oxide levels in patients with oral lichen planus and healthy individuals. Methods: Saliva was collected by spitting method. Unstimulated whole saliva thus collected was refrigerated at 4°C, and processed within 24 h for the estimation of nitric oxide levels which was done using Griess reaction. The results were analyzed using Student′s " t" test. Results: There was statistically significant difference in the levels of salivary nitric oxide between the study and control groups. Conclusions: The present study clearly indicates a significant increase in salivary nitric oxide levels in oral lichen planus patients as compared to controls.

  15. Effects of simulated microgravity on nitric oxide level in cardiac myocytes and its mechanism

    Institute of Scientific and Technical Information of China (English)

    XIONG; Jianghui; (熊江辉); LI; Yinghui; (李莹辉); NIE; Jielin; (聂捷琳)

    2003-01-01

    The depression of cardiac contractility induced by space microgravity is an important issue of aerospace medicine research, while its precise mechanism is still unknown. In the present study, we explored effects of simulated microgravity on nitric oxide (NO) level, inducible nitric oxide synthase (iNOS) expression and related regulative mechanism using electron spin resonance (ESR) spectroscopy, immunocytochemistry and in situ hybridization. We found a remarkable increase of NO level and up-regulation of iNOS and iNOS mRNA expression in rat cardiac myocytes under simulated microgravity. Staurosporine (a nonselective protein kinase inhibitor), calphostin C (a selective protein kinase C inhibitor), partially inhibited the effect of simulated microgravity. Thus regulative effect of simulated microgravity on iNOS expression is mediated at least partially via activation of protein kinase C. These results indicate that NO system in cardiac myocytes is sensitive to simulated microgravity and may play an important role in the depression of cardiac contractility induced by simulated microgravity.

  16. Relationship Between the Levels of Oxidative Stress in Mesenteric and Peripheral Serum and Clinicopathological Variables in Colorectal Cancer

    OpenAIRE

    Sevim Purisa; Ahu Sarbay Kemik; Özgür Kemik; Ahmet Fikret Yücel,; İshak Sefa Tüzün

    2012-01-01

    Objective: To explore the differences existing between the levels of oxidative stress in peripheral and mesenteric serum in patients with colorectal cancer. Material and Methods: One hundred fifty patients with colorectal cancer who underwent surgery between May 2005 and March 2010 were prospectively analyzed. The differences between oxidative stress parameters in their peripheral and mesenteric blood were measured. The associations between peripheral and mesenteric levels and the staging and...

  17. Effect of age and eosinophil number on fractional exhaled nitric oxide level in non-asthmatic children in shanghai.

    OpenAIRE

    Wei Liu; Jizhi Chu; Li Sun; Zhiqin Shen; Yan Liu; Qing Peng; Xiwen Gao

    2014-01-01

    This study aimed to identify the relationship between fractional exhaled nitric oxide (FeNO) level and potential factors in non-asthmatic children from Shanghai, China. From March to April 2012, the school-aged children fulfilling the inclusion criteria were recruited. The FeNO levels of non-asthmatic children were detected by the Nano Coulomb nitric oxide analyzer. Questionnaires were recorded, including personal data, family illness history and daily habits. In addition, not only the number...

  18. Plasma levels of interleukin-10 and nitric oxide in response to two different desflurane anesthesia flow rates

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    Dilek Kalayci

    2014-07-01

    Full Text Available OBJECTIVE: This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determine whether there is a correlation between these two variables and if different desflurane anesthesia flow rates influence nitric oxide and interleukin-10 concentrations in circulation. MATERIALS AND METHODS: Forty patients between 18 and 70 years and ASA I-II physical status who were scheduled to undergo thyroidectomy were enrolled in the study. INTERVENTIONS: Patients were allocated into two groups to receive two different desflurane anesthesia flow rates: high flow (Group HF and low flow (Group LF. MEASUREMENTS: Blood samples were drawn at the beginning (t 0 and end (t 1 of the operation and after 24 h (t 2. Plasma interleukin-10 and nitric oxide levels were measured using an enzyme-linked-immunosorbent assay and a Griess reagents kit, respectively. Hemodynamic and respiratory parameters were assessed. RESULTS: There was no statistically significant difference between the two groups with regard to interleukin-10 levels at the times of measurement. Interleukin-10 levels were increased equally in both groups at times t 1 and t 2 compared with preoperative concentrations. For both groups, nitric oxide circulating concentrations were significantly reduced at times t 1 and t 2 compared with preoperative concentrations. However, the nitric oxide value was lower for Group HF compared to Group LF at t 2. No correlation was found between the IL-10 and nitric oxide levels. CONCLUSION: Clinical usage of two different flow anesthesia forms with desflurane may increase interleukin-10 levels both in Group HF and Group LF; nitric oxide levels circulating concentrations were significantly reduced at times t 1 and t 2 compared with preoperative concentrations; however, at 24 h postoperatively they were higher in Group LF compared to Group HF. No correlation was detected between interleukin-10 and nitric oxide levels.

  19. Low-level 14C methane oxidation rate measurements modified for remote field settings

    Science.gov (United States)

    Pack, M. A.; Pohlman, J.; Ruppel, C. D.; Xu, X.

    2012-12-01

    Aerobic methane oxidation limits atmospheric methane emissions from degraded subsea permafrost and dissociated methane hydrates in high latitude oceans. Methane oxidation rate measurements are a crucial tool for investigating the efficacy of this process, but are logistically challenging when working on small research vessels in remote settings. We modified a low-level 14C-CH4 oxidation rate measurement for use in the Beaufort Sea above hydrate bearing sediments during August 2012. Application of the more common 3H-CH4 rate measurement that uses 106 times more radioactivity was not practical because the R/V Ukpik cannot accommodate a radiation van. The low-level 14C measurement does not require a radiation van, but careful isolation of the 14C-label is essential to avoid contaminating natural abundance 14C measurements. We used 14C-CH4 with a total activity of 1.1 μCi, which is far below the 100 μCi permitting level. In addition, we modified field procedures to simplify and shorten sample processing. The original low-level 14C-CH4 method requires 6 steps in the field: (1) collect water samples in glass serum bottles, (2) inject 14C-CH4 into bottles, (3) incubate for 24 hours, (4) filter to separate the methanotrophic bacterial cells from the aqueous sample, (5) kill the filtrate with sodium hydroxide (NaOH), and (6) purge with nitrogen to remove unused 14C-CH4. Onshore, the 14C-CH4 respired to carbon dioxide or incorporated into cell material by methanotrophic bacteria during incubation is quantified by accelerator mass spectrometry (AMS). We conducted an experiment to test the possibility of storing samples for purging and filtering back onshore (steps 4 and 6). We subjected a series of water samples to steps 1-3 & 5, and preserved with mercuric chloride (HgCl2) instead of NaOH because HgCl2 is less likely to break down cell material during storage. The 14C-content of the carbon dioxide in samples preserved with HgCl2 and stored for up to 2 weeks was stable

  20. Effect of drinking Arabian Qahwa on fractional exhaled nitric oxide levels in healthy nonsmoking Saudi adults

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    Syed Shahid Habib

    2012-01-01

    Full Text Available Objectives: Fractional exhaled nitric oxide (FENO is an emerging marker of inflammation in respiratory diseases. However, it is affected by a number of confounding factors. We aimed to study the effect of drinking Arabian Qahwa on FENO in non-smoking Saudi healthy adults. Methods: We recruited 12 nonsmoker healthy male adults aged 36.6 ± 2.7 (21-50 years. All subjects were free from acute respiratory infections or allergies and had normal ventilatory functions and serum IgE levels. At 8 am in the morning, their baseline values of FENO were recorded. They had not taken tea or coffee in the morning and had taken similar light breakfast. They were given three cups of Arabian Qahwa to drink and then after every 30 minutes, serial levels of FENO were recorded. Results: Average FENO levels at baseline were 28.73 ± 9.33 (mean ± SD parts per billion (ppb. The mean FENO levels started to decrease significantly after 30 minutes of drinking Arabian Qahwa (P=0.002. This decrease in FENO level was further observed till two hours after Qahwa drinking and then it started to increase in next 90 minutes but still was significantly lower than the baseline (P=0.002. The mean FENO level recorded after 4 hours was 27.22 ± 10.22 (P=0.039. Conclusions: FENO levels were significantly lowered by intake of Arabian Qahwa and this effect remains for about 4 hours. Therefore, history of recent Qahwa intake and abstinence is essential before performance of FENO and its interpretation.

  1. Postoperative changes in serum cytokines profile and nitric oxide levels in patients with cystic echinococcosis

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    Refik M.

    2005-09-01

    Full Text Available The aim of the present study was to examine serum cytokines and nitric oxide (NO levels in patients with cystic echinococcosis (CE. 28 patients with CE were studied and all underwent surgery. Serum levels of tumour necrosis factor-alpha (TNF-α, interleukin IL- 1β, receptor of soluble IL-2R (sIL-2R, IL-6, IL-8, nitrate/nitrite, and C-reactive protein (CRP were determined before and after induction of treatment. Data were compared with those obtained from 28 healthy volunteers. IL-6 was elevated in all CE patients (100%. IL-8 was increased in 11/28 (39.3%. Increased levels of IL-2R and TNF-α were found in a limited number of them particularly those showing cysts in the central area of the liver (5/28, 6/28. IL-1β level was not elevated in any patient except in secondary severe CE. CRP and nitrate/nitrite levels were also increased. A positive correlation between CRP and IL-6 (r = 0.74; p < 0.001 was found confirming the link between inflammation due to CE and activation of monocytes. All patients completely recovered and the levels of the studied parameters reverted to normal levels except one patient in whom severe recurrent disease occurred two years after the first operation. These results suggest that there are different immunoregulatory events and cytokines response during CE and may be in part related to slight monocytosis and in part to Th2 activation. IL-6, NO and CRP were unambiguously involved in the host parasite interaction and therefore may be useful markers in monitoring CE management and evaluating surgical stress.

  2. Cytokine profile and nitric oxide levels in sera from patients with brucellosis

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    Refik M.

    2004-01-01

    Full Text Available The aims of this study were to investigate the serum levels of some cytokines [tumor necrosis factor-alpha (TNF-alpha, interleukin 1ß (IL-1ß, IL-2R, IL-6, and IL-8] and nitric oxide (NO levels in patients with untreated brucellosis and to test the correlation of these parameters with each other. The study was conducted on 67 subjects, 37 patients with brucellosis and 30 healthy individuals with no history of Brucella infection. Brucellosis was identified by a positive blood culture and/or increased Brucella antibodies in serological tests in addition to compatible clinical symptoms. Cytokine profile analysis was performed by the immulite chemiluminescent enzyme immunometric assay whose inter- and intra-assay coefficients of variance were 2.6-3.6 and 4.4-8.5%, respectively. The levels of nitrites/nitrates, which are representative of NO levels, were measured by the Griess method. Patients with brucellosis had significantly elevated serum levels of nitrites/nitrates, IL-2R, IL-6 and IL-8 (mean ± SD, 102.8 ± 23.8 µmol/l, 806.1 ± 58.5 U/ml, 21.1 ± 2.3 pg/ml, and 8.8 ± 1.6 pg/ml, respectively compared to healthy controls, whereas TNF-alpha and IL-1ß levels were unchanged. No statistically significant correlation was detected between any of the studied cytokine levels and nitrate/nitrite concentrations according to Pearson's linear correlation test. We conclude that only IL-6, IL-8 and IL-2R are elevated in brucellosis and the extent of elevation depends on the severity and clinical pattern of the disease. Moderate elevation in serum NO was comparable to that observed in previous studies. This explains the absence or very rare occurrence of septic shock in brucellosis.

  3. An overview on therapeutics attenuating amyloid β level in Alzheimer's disease: targeting neurotransmission, inflammation, oxidative stress and enhanced cholesterol levels.

    Science.gov (United States)

    Zhou, Xiaoling; Li, Yifei; Shi, Xiaozhe; Ma, Chun

    2016-01-01

    Alzheimer's disease (AD) is the most common underlying cause of dementia, and novel drugs for its treatment are needed. Of the different theories explaining the development and progression of AD, "amyloid hypothesis" is the most supported by experimental data. This hypothesis states that the cleavage of amyloid precursor protein (APP) leads to the formation of amyloid beta (Aβ) peptides that congregate with formation and deposition of Aβ plaques in the frontal cortex and hippocampus. Risk factors including neurotransmitter modulation, chronic inflammation, metal-induced oxidative stress and elevated cholesterol levels are key contributors to the disease progress. Current therapeutic strategies abating AD progression are primarily based on anti-acetylcholinesterase (AChE) inhibitors as cognitive enhancers. The AChE inhibitor, donepezil, is proven to strengthen cognitive functions and appears effective in treating moderate to severe AD patients. N-Methyl-D-aspartate receptor antagonist, memantine, is also useful, and its combination with donepezil demonstrated a strong stabilizing effect in clinical studies on AD. Nonsteroidal anti-inflammatory drugs delayed the onset and progression of AD and attenuated cognitive dysfunction. Based upon epidemiological evidence and animal studies, antioxidants emerged as potential AD preventive agents; however, clinical trials revealed inconsistencies. Pharmacokinetic and pharmacodynamic profiling demonstrated pleiotropic functions of the hypolipidemic class of drugs, statins, potentially contributing towards the prevention of AD. In addition, targeting the APP processing pathways, stimulating neuroprotective signaling mechanisms, using the amyloid anti-aggregants and Aβ immunotherapy surfaced as well-tested strategies in reducing the AD-like pathology. Overall, this review covers mechanism of inducing the Aβ formation, key risk factors and major therapeutics prevalent in the AD treatment nowadays. It also delineates the need

  4. Tunable Ether Production via Coupling of Aldehydes or Aldehyde/Alcohol over Hydrogen-Modified Gold Catalysts at Low Temperatures.

    Science.gov (United States)

    Pan, Ming; Brush, Adrian J; Dong, Guangbin; Mullins, C Buddie

    2012-09-01

    Ethers are an important group of organic compounds that are primarily prepared via homogeneous catalysis, which can lead to operational and environmental issues. Here we demonstrate the production of ethers via heterogeneous catalysis over H adatom-covered gold at temperatures lower than 250 K. Symmetrical ethers can be formed via a self-coupling reaction of corresponding aldehydes; for example, homocoupling of acetaldehyde and propionaldehyde yields diethyl ether and di-n-propyl ether, respectively. In addition, coupling reactions between alcohols and aldehydes, with different carbon chain lengths, are observed via the production of the corresponding unsymmetrical ethers. A reaction mechanism is proposed, suggesting that an alcohol-like intermediate via partial hydrogenation of aldehydes on the surface plays a key role in these reactions. These surface chemical reactions suggest possible heterogeneous routes to low-temperature production of ethers. PMID:26292142

  5. Effect of yogic exercise on super oxide dismutase levels in diabetics

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    Mahapure Hemant

    2008-01-01

    Full Text Available Context : Reactive oxygen species are known to aggravate disease progression. To counteract their harmful effects, the body produces various antioxidant enzymes, viz , superoxide dismutase, glutathione reductase etc. Literature reviews revealed that exercises help to enhance antioxidant enzyme systems; hence, yogic exercises may be useful to combat various diseases. Aims : This study aims to record the efficacy of yoga on superoxide dismutase, glycosylated hemoglobin (Hb and fasting blood glucose levels in diabetics. Settings and Design: Forty diabetics aged 40-55 years were assigned to experimental (30 and control (10 groups. The experimental subjects underwent a Yoga program comprising of various Asanas (isometric type exercises and Pranayamas (breathing exercises along with regular anti-diabetic therapy whereas the control group received anti-diabetic therapy only. Materials and Methods : Heparinized blood samples were used to determine erythrocyte superoxide dismutase (SOD activity and glycosylated Hb levels and fasting blood specimens collected in fluoride Vacutainers were used for assessing blood glucose. Statistical Analysis Used : Data were analyzed by using 2 x 2 x 3 Factorial ANOVA followed by Scheffe′s posthoc test. Results : The results revealed that Yogic exercise enhanced the levels of Superoxide dismutase and reduced glycosylated Hb and glucose levels in the experimental group as compared to the control group. Conclusion : The findings conclude that Yogic exercises have enhanced the antioxidant defence mechanism in diabetics by reducing oxidative stress.

  6. Phenolic compounds protect HepG2 cells from oxidative damage: relevance of glutathione levels.

    Science.gov (United States)

    Lima, Cristovao F; Fernandes-Ferreira, Manuel; Pereira-Wilson, Cristina

    2006-10-19

    In the present work, the potential hepatoprotective effects of five phenolic compounds against oxidative damages induced by tert-butyl hydroperoxide (t-BHP) were evaluated in HepG2 cells in order to relate in vitro antioxidant activity with cytoprotective effects. t-BHP induced considerable cell damage in HepG2 cells as shown by significant LDH leakage, increased lipid peroxidation, DNA damage as well as decreased levels of reduced glutathione (GSH). All tested phenolic compounds significantly decreased cell death induced by t-BHP (when in co-incubation). If the effects of quercetin are given the reference value 1, the compounds rank in the following order according to inhibition of cell death: luteolin (4.0) > quercetin (1.0) > rosmarinic acid (0.34) > luteolin-7-glucoside (0.30) > caffeic acid (0.21). The results underscore the importance of the compound's lipophilicity in addition to its antioxidant potential for its biological activity. All tested phenolic compounds were found to significantly decrease lipid peroxidation and prevent GSH depletion induced by t-BHP, but only luteolin and quercetin significantly decreased DNA damage. Therefore, the lipophilicity of the natural antioxidants tested appeared to be of even greater importance for DNA protection than for cell survival. The protective potential against cell death was probably achieved mainly by preventing intracellular GSH depletion. The phenolic compounds studied here showed protective potential against oxidative damage induced in HepG2 cells. This could be beneficial against liver diseases where it is known that oxidative stress plays a crucial role. PMID:16857214

  7. Brain BDNF levels are dependent on cerebrovascular endothelium-derived nitric oxide.

    Science.gov (United States)

    Banoujaafar, Hayat; Monnier, Alice; Pernet, Nicolas; Quirié, Aurore; Garnier, Philippe; Prigent-Tessier, Anne; Marie, Christine

    2016-09-01

    Scientific evidence continues to demonstrate a link between endothelial function and cognition. Besides, several studies have identified a complex interplay between nitric oxide (NO) and brain-derived neurotrophic factor (BDNF), a neurotrophin largely involved in cognition. Therefore, this study investigated the link between cerebral endothelium-derived NO and BDNF signaling. For this purpose, levels of BDNF and the phosphorylated form of endothelial NO synthase at serine 1177 (p-eNOS) were simultaneously measured in the cortex and hippocampus of rats subjected to either bilateral common carotid occlusion (n = 6), physical exercise (n = 6) or a combination of both (n = 6) as experimental approaches to modulate flow-induced NO production by the cerebrovasculature. Tropomyosin-related kinase type B (TrkB) receptors and its phosphorylated form at tyrosine 816 (p-TrkB) were also measured. Moreover, we investigated BDNF synthesis in brain slices exposed to the NO donor glyceryl trinitrate. Our results showed increased p-eNOS and BDNF levels after exercise and decreased levels after vascular occlusion as compared to corresponding controls, with a positive correlation between changes in p-eNOS and BDNF (r = 0.679). Exercise after vascular occlusion did not change levels of these proteins. Gyceryl trinitrate increased proBDNF and BDNF levels in brain slices, thus suggesting a possible causal relationship between NO and BDNF. Moreover, vascular occlusion, like exercise, resulted in increased TrkB and p-TrkB levels, whereas no change was observed with the combination of both. These results suggest that brain BDNF signaling may be dependent on cerebral endothelium-derived NO production. PMID:27306299

  8. High-fat diet induces changes in adipose tissue trans-4-oxo-2-nonenal and trans-4-hydroxy-2-nonenal levels in a depot-specific manner.

    Science.gov (United States)

    Long, Eric K; Olson, Dalay M; Bernlohr, David A

    2013-10-01

    Protein carbonylation is the covalent modification of proteins by α,β-unsaturated aldehydes produced by nonenzymatic lipid peroxidation of polyunsaturated fatty acids. The most widely studied aldehyde product of lipid peroxidation, trans-4-hydroxy-2-nonenal (4-HNE), is associated with obesity-induced metabolic dysfunction and has demonstrated reactivity toward key proteins involved in cellular function. However, 4-HNE is only one of many lipid peroxidation products and the lipid aldehyde profile in adipose tissue has not been characterized. To further understand the role of oxidative stress in obesity-induced metabolic dysfunction, a novel LC-MS/MS method was developed to evaluate aldehyde products of lipid peroxidation and applied to the analysis of adipose tissue. 4-HNE and trans-4-oxo-2-nonenal (4-ONE) were the most abundant aldehydes present in adipose tissue. In high fat-fed C57Bl/6J and ob/ob mice the levels of lipid peroxidation products were increased 5- to 11-fold in epididymal adipose, unchanged in brown adipose, but decreased in subcutaneous adipose tissue. Epididymal adipose tissue of high fat-fed mice also exhibited increased levels of proteins modified by 4-HNE and 4-ONE, whereas subcutaneous adipose tissue levels of these modifications were decreased. High fat feeding of C57Bl/6J mice resulted in decreased expression of a number of genes linked to antioxidant biology selectively in epididymal adipose tissue. Moreover, TNFα treatment of 3T3-L1 adipocytes resulted in decreased expression of GSTA4, GPx4, and Prdx3 while upregulating the expression of SOD2. These results suggest that inflammatory cytokines selectively downregulate antioxidant gene expression in visceral adipose tissue, resulting in elevated lipid aldehydes and increased protein carbonylation.

  9. Oxygen level: the dominant of resistive switching characteristics in cerium oxide thin films

    International Nuclear Information System (INIS)

    Currently, resistive switching mechanisms in metal oxide thin films are not clearly understood due to lack of solid evidence. In this work, the switching behaviour of the Au/CeO2/conductive glass structure was analysed, where reproducible and pronounced resistive switching characteristics were obtained. The role of oxygen vacancies in switching characteristics was investigated. The concentration of oxygen vacancies in the CeO2 thin films was controlled by post-annealing and monitored by x-ray photon spectroscopy. The reduction in the switching ratio and the intensity of the peak associated with oxygen concentration O 1s level after annealing treatment confirmed the dominating role of oxygen vacancies in switching behaviour.

  10. Acetic acid assisted cobalt methanesulfonate catalysed chemoselective diacetylation of aldehydes

    Institute of Scientific and Technical Information of China (English)

    Min Wang; Zhi Guo Song; Hong Gong; Heng Jiang

    2008-01-01

    Cobalt methanesulfonate in combination with acetic acid catalysed the chemoselective diacetylation of aldehyde with acetic anhydride at room temperature under solvent free conditions. After reaction, cobalt methanesulfonate can be easily recovered and mused many times. The reaction was mild and efficient with good to high yields.

  11. Reaction of benzoxasilocines with aromatic aldehydes: Synthesis of homopterocarpans

    Directory of Open Access Journals (Sweden)

    Rodríguez-García Ignacio

    2007-02-01

    Full Text Available Abstract Condensation of 2H-benzo[g][1,2]oxasilocines with aromatic aldehydes in the presence of boron trifluoride affords mixtures of cis/trans 2-phenyl-3-vinylchromans with moderate yields. These can be transformed into homopterocarpans, a synthetic group of substances homologous to the natural isoflavonoid pterocarpans.

  12. Daily grape juice consumption reduces oxidative DNA damage and plasma free radical levels in healthy Koreans

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yoo Kyoung; Park, Eunju; Kim, Jung-Shin; Kang, Myung-Hee

    2003-08-28

    Grape contains flavonoids with antioxidant properties which are believed to be protective against various types of cancer. This antioxidative protection is possibly provided by the effective scavenging of reactive oxygen species (ROS), thus defending cellular DNA from oxidative damage and potential mutations. This study of healthy adults tested whether a daily regimen of grape juice supplementation could reduce cellular DNA damage in peripheral lymphocytes and reduce the amount of free radicals released. Sixty-seven healthy volunteers (16 women and 51 men) aged 19-57 years were given 480 ml of grape juice daily for 8 weeks in addition to their normal diet, and blood samples were drawn before and after the intervention. The DNA damage was determined by using the single cell gel (comet) assay with alkaline electrophoresis and was quantified by measuring tail length (TL). Levels of free radicals were determined by reading the lucigenin-perborate ROS generating source, using the Ultra-Weak Chemiluminescence Analyzer System. Grape juice consumption resulted in a significant decrease in lymphocyte DNA damage expressed by TL (before supplementation: 88.75{+-}1.55 {mu}m versus after supplementation: 70.25{+-}1.31 {mu}m; P=0.000 by paired t-test). Additionally, grape juice consumption for 8 weeks reduced the ROS/photon count by 15%, compared to the beginning of the study. The preventive effect of grape juice against DNA damage was simultaneously shown in both sexes. These results indicate that the consumption of grape juice may increase plasma antioxidant capacity, resulting in reduced DNA damage in peripheral lymphocytes achieved at least partially by a reduced release of ROS. Our findings support the hypothesis that polyphenolic compounds contained in grape juice exert cancer-protective effects on lymphocytes, limiting oxidative DNA damage possibly via a decrease in free radical levels.

  13. Nitric oxide mitigates salt stress by regulating levels of osmolytes and antioxidant enzymes in chickpea

    Directory of Open Access Journals (Sweden)

    Parvaiz eAhmad

    2016-03-01

    Full Text Available This work was designed to evaluate whether external application of nitric oxide (NO in the form of its donor S-nitroso-N-acetylpenicillamine (SNAP could mitigate the deleterious effects of NaCl stress on chickpea (Cicer arietinum L. plants. SNAP (50 μM was applied to chickpea plants grown under non-saline and saline conditions (50 and 100 mM NaCl. Salt stress negatively affected growth and biomass yield, leaf relative water content (LRWC and chlorophyll content of chickpea plants. High salinity increased electrolyte leakage, carotenoid content and the levels of osmolytes (proline, glycine betaine, soluble proteins and soluble sugars, hydrogen peroxide (H2O2 and malondialdehyde (MDA, as well as the activities of antioxidant enzymes, such as superoxide dismutase (SOD, catalase (CAT, ascorbate peroxidase (APX, and glutathione reductase (GR in chickpea plants. Expression of the representative SOD, CAT and APX genes examined was also up-regulated in chickpea plants by salt stress. On the other hand, exogenous application of NO to salinized plants enhanced the growth parameters, LRWC, photosynthetic pigment production and levels of osmolytes, as well as the activities of examined antioxidant enzymes which is correlated with up-regulation of the examined SOD, CAT and APX genes, in comparison with plants treated with NaCl only. Furthermore, electrolyte leakage, H2O2 and MDA contents showed decline in salt-stressed plants supplemented with NO as compared with those in NaCl-treated plants alone. Thus, the exogenous application of NO protected chickpea plants against salt-induced oxidative damage by enhancing the biosynthesis of antioxidant enzymes, thereby improving plant growth under saline stress. Taken together, our results demonstrate that NO has capability to mitigate the adverse effects of high salinity on chickpea plants by improving LRWC, photosynthetic pigment biosyntheses, osmolyte accumulation and antioxidative defense system.

  14. Daily grape juice consumption reduces oxidative DNA damage and plasma free radical levels in healthy Koreans

    International Nuclear Information System (INIS)

    Grape contains flavonoids with antioxidant properties which are believed to be protective against various types of cancer. This antioxidative protection is possibly provided by the effective scavenging of reactive oxygen species (ROS), thus defending cellular DNA from oxidative damage and potential mutations. This study of healthy adults tested whether a daily regimen of grape juice supplementation could reduce cellular DNA damage in peripheral lymphocytes and reduce the amount of free radicals released. Sixty-seven healthy volunteers (16 women and 51 men) aged 19-57 years were given 480 ml of grape juice daily for 8 weeks in addition to their normal diet, and blood samples were drawn before and after the intervention. The DNA damage was determined by using the single cell gel (comet) assay with alkaline electrophoresis and was quantified by measuring tail length (TL). Levels of free radicals were determined by reading the lucigenin-perborate ROS generating source, using the Ultra-Weak Chemiluminescence Analyzer System. Grape juice consumption resulted in a significant decrease in lymphocyte DNA damage expressed by TL (before supplementation: 88.75±1.55 μm versus after supplementation: 70.25±1.31 μm; P=0.000 by paired t-test). Additionally, grape juice consumption for 8 weeks reduced the ROS/photon count by 15%, compared to the beginning of the study. The preventive effect of grape juice against DNA damage was simultaneously shown in both sexes. These results indicate that the consumption of grape juice may increase plasma antioxidant capacity, resulting in reduced DNA damage in peripheral lymphocytes achieved at least partially by a reduced release of ROS. Our findings support the hypothesis that polyphenolic compounds contained in grape juice exert cancer-protective effects on lymphocytes, limiting oxidative DNA damage possibly via a decrease in free radical levels

  15. Effect of Different Selenium Supplementation Levels on Oxidative Stress, Cytokines, and Immunotoxicity in Chicken Thymus.

    Science.gov (United States)

    Wang, Yachao; Jiang, Li; Li, Yuanfeng; Luo, Xuegang; He, Jian

    2016-08-01

    This study assessed the effects of different selenium (Se) supplementation levels on oxidative stress, cytokines, and immunotoxicity in chicken thymus. A total of 180 laying hens (1 day old; Mianyang, China) were randomly divided into 4 groups (n = 45). The chickens were maintained either on a basic diet (control group) containing 0.2 mg/kg Se, a low-supplemented diet containing 5 mg/kg Se, a medium-supplemented diet containing 10 mg/kg Se, or a high-supplemented diet containing 15 mg/kg Se for 15, 30, and 45 days, respectively. Over the entire experimental period, serum and thymus samples were collected and used for the detection of the experimental index. The results indicated that the antioxidative enzyme activities and messenger RNA (mRNA) levels of antioxidative enzymes, IFN-γ and IL-2 in the thymus, and the content of IFN-γ and IL-2 in the serum of excessive-Se-treated chickens at all time points (except for the 5 mg/kg Se supplement group at 15 days) were significantly decreased (P < 0.05) compared to the corresponding control groups. Interestingly, a significantly increase (P < 0.05) in the content of IFN-γ was observed in the serum and thymus in the 5 mg/kg Se supplement group at 15 and 30 days compared to the corresponding control groups. In histopathological examination, the thymus tissue from excessive-Se-treated chickens revealed different degrees of cortex drop, incrassation of the medulla, and degeneration of the reticular cells. These results suggested that the excessive Se could result in a decrease in immunity, an increase in oxidative damage, and a series of clinical pathology changes, such as cortex drop, incrassation of the medulla, and degeneration of the reticular cells. PMID:26740218

  16. Tandem Aldol Condensation – Platinacycle-Catalyzed Addition Reactions of Aldehydes, Methyl Ketones and Arylboronic Acids

    OpenAIRE

    Liao, Yuan-Xi; Hu, Qiao-Sheng

    2012-01-01

    Tandem aldol condensation of aldehydes with methyl ketones followed by anionic four-electron donor-based (Type I) platinacycle-catalyzed addition reactions of arylboronic acids to form β-arylated ketones is described. Good to excellent yields of β-arylated ketones were obtained for the tandem reactions of aromatic/aliphatic aldehydes, methyl ketones and arylboronic acids, and moderate yields were observed for the tandem reaction with α, β-unsaturated aldehydes as the aldehyde source.

  17. Analysis of oxidative stress status through MN test and serum MDA levels in PCOS women.

    Science.gov (United States)

    Deepika, M L N; Nalini, S; Maruthi, G; Ramchander, Vinish; Ranjith, K; Latha, K Prasanna; Rani, V Usha; Jahan, P

    2014-04-01

    Polycystic Ovary Syndrome (PCOS) is a multifactorial reproductive healthcare problem affecting 4-12% of women and a leading cause of female infertility worldwide. The potential genetic contributors of PCOS are unclear. However, over the past decade emerging evidence has shown that increased Oxidative Stress (OS) and decreased antioxidant status were often linked with PCOS. The present case-control study was aimed to assess the reactive oxygen species induced OS in women from South India. A total of 164 individuals comprising of 89 patients and 75 controls were enrolled in the present study. For all the subjects, the frequency of micronucleated cells (MNC) in epithelial samples and serum Malondialdehyde (MDA) levels were estimated to assess genomic instability and cytotoxicity respectively. A statistically significant difference between the groups were identified with respect to Body Mass Index, Waist to Hip Ratio, luteinizing hormone and prolactin levels (< 0.05), however the mean follicle stimulating hormone was not different between the groups (p = 0.055). The frequency of MN cells (5.89 ± 4.86 vs. 2.24 ± 2.01) and mean serum MDA (360.84 ± 87.08 vs. 301.70 ± 82.82) levels were considerably higher in patients than controls (p = < 0.0001), furthermore, a positive correlation was observed between MNC and MDA levels in patients (r = 0.349, p = 0.0008) and not in controls (r = 0.104, p = 0.37), suggest high OS in PCOS women. Therefore, MN assay and serum MDA levels may serve together or individually as biomarkers of OS in PCOS women. PMID:25911850

  18. Effects of cell phone radiation on lipid peroxidation, glutathione and nitric oxide levels in mouse brain during epileptic seizure.

    Science.gov (United States)

    Esmekaya, Meric Arda; Tuysuz, Mehmet Zahid; Tomruk, Arın; Canseven, Ayse G; Yücel, Engin; Aktuna, Zuhal; Keskil, Semih; Seyhan, Nesrin

    2016-09-01

    The objective of the this study was to evaluate the effects of cellular phone radiation on oxidative stress parameters and oxide levels in mouse brain during pentylenetetrazole (PTZ) induced epileptic seizure. Eight weeks old mice were used in the study. Animals were distributed in the following groups: Group I: Control group treated with PTZ, Group II: 15min cellular phone radiation+PTZ treatment+30min cellular phone radiation, Group III: 30min cellular phone radiation+PTZ treatment+30min cellular phone radiation. The RF radiation was produced by a 900MHz cellular phone. Lipid peroxidation, which is the indicator of oxidative stress was quantified by measuring the formation of thiobarbituric acid reactive substances (TBARS). The glutathione (GSH) levels were determined by the Ellman method. Tissue total nitric oxide (NOx) levels were obtained using the Griess assay. Lipid peroxidation and NOx levels of brain tissue increased significantly in group II and III compared to group I. On the contrary, GSH levels were significantly lower in group II and III than group I. However, no statistically significant alterations in any of the endpoints were noted between group II and Group III. Overall, the experimental findings demonstrated that cellular phone radiation may increase the oxidative damage and NOx level during epileptic activity in mouse brain. PMID:26836107

  19. A STUDY OF OXIDANTS-ANTIOXIDANTS BALANCE IN ASTHMATIC PATIENTS

    Directory of Open Access Journals (Sweden)

    Lokendra

    2014-06-01

    Full Text Available : This study was done to observe the serum/plasma oxidant-antioxidant status among asthmatic patients. Plasma MDA (Malon-di-aldehyde, an oxidant and Serum SOD (superoxide dismutase, an antioxidant, were assayed among asthmatic patients and their mean values were compared with healthy volunteer controls. Values were also observed in different age groups. The difference in mean pMDA level was found statistically significantly among cases and control, higher among asthmatic patients. Likewise, s-SOD level was significantly reduced among asthmatic patients. Clearly, there was an imbalance between oxidants and antioxidants levels among asthmatic patients and this consideration may be helpful in proper planning of basket of anti-asthma interventions. Future studies are recommended.

  20. Development of an LC-MS/MS analytical method for the simultaneous measurement of aldehydes from polyunsaturated fatty acids degradation in animal feed.

    Science.gov (United States)

    Douny, Caroline; Bayram, Pinar; Brose, François; Degand, Guy; Scippo, Marie-Louise

    2016-05-01

    Knowing that polyunsaturated fatty acids can lead to the formation of potentially toxic aldehydes as secondary oxidation products, an analytical method using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) detection was developed to measure the concentration of eight aldehydes in animal feed: malondialdehyde (MDA), 4-hydroxy-2-nonenal (4-HNE), 4-hydroxy-2-hexenal (4-HHE), crotonaldehyde (CRT), benzaldehyde (BNZ), hexanal (HXL), 2,4-nonadienal, and 2,4-decadienal. The developed method was validated according to the criteria and procedure described in international standards. The evaluated parameters were specificity/selectivity, recovery, precision, accuracy, uncertainty, limits of detection and quantification, using the concept of accuracy profiles. These parameters were determined during experiments conducted over three different days with ground Kellogg's® Corn Flakes® cereals as model matrix for animal feed and spiked at different levels of concentration. Malondialdehyde, 4-HHE, 4-HNE, crotonaldehyde, benzaldehyde, and hexanal can be analyzed in the same run in animal feed with a very good accuracy, with recovery rates ranging from 86 to 109% for a working range going from 0.16 to 12.50 mg/kg. The analysis of 2,4-nonadienal and 2,4-decadienal can also be performed but in a limited range of concentration and with a limited degree of accuracy. Their recovery rates ranged between 54 and 114% and coefficient of variation for the intermediate precision between 11 and 25% for these two compounds. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27443200

  1. Plasma nitric oxide level in familial Mediterranean fever and its modulations by Immuno-Guard.

    Science.gov (United States)

    Panossian, A; Hambartsumyan, M; Panosyan, L; Abrahamyan, H; Mamikonyan, G; Gabrielyan, E; Amaryan, G; Astvatsatryan, V; Wikman, G

    2003-09-01

    Familial Mediterranean fever (FMF) is a recessively inherited inflammatory disorder, characterised by recurrent attacks of fever and serositis. Since nitric oxide (NO) is an important mediator of inflammation, the production of NO (assessed as the accumulation of nitrate and nitrite and measured by capillary electrophoresis) in blood plasma of FMF patients during acute attacks (active) and attack-free periods (inactive) of the disease has been determined and compared with NO levels found in healthy volunteers (control group C). Thirty-six FMF patients were involved in a placebo-controlled double-blind study (group A received the drug, group B the placebo) of the effects of Immuno-Guard, a novel herbal preparation which relieves the severity and longevity of FMF attacks on NO blood levels. Thirty-two FMF patients (group D) being permanently treated with colchicine were also examined with respect to their NO blood level. No significant differences were found between the NO levels in blood of inactive FMF patients and those of control group C, or between inactive colchicine-treated group D patients and inactive patients of groups A and B, a finding which is atypical for chronic inflammatory disorders. Significantly lower plasma NO levels were found in active FMF patients in groups A and B compared with inactive patients in those groups (p=0.031 and 0.036, respectively) and with patients of group D and the control group C (p=0.0235 and 0.0453, respectively). The decrease of NO in blood of FMF patients may trigger the generation of fever by initiating the production of pro-inflammatory IL-6. Plasma NO levels in inactive FMF patients were significantly increased during attack-free periods following treatment with Immuno-Guard. The preparation has a normalising effect both on NO and IL-6 blood levels in FMF patients during attacks, demonstrating a relationship between the beneficial effect of Immuno-Guard in reducing the severity of inflammatory attacks in FMF patients

  2. Portal pressure and blood nitric oxide levels as predictors of outcome in biliary atresia

    Directory of Open Access Journals (Sweden)

    Vikram Khanna

    2016-01-01

    Full Text Available Aim: To evaluate the incidence of portal hypertension (PHT in biliary atresia (BA patients and to monitor its progress after Kasai portoenterostomy (KP by measuring nitric oxide (NO levels in peripheral blood. Materials and Methods: A prospective cross-sectional study conducted over a period of 2 years. Intraoperative portal pressure (PP and blood NO levels at presentation, 1-month, 3-month, and 6-month follow-up, were correlated with clinical and biochemical parameters in BA patients. The mean NO level in age-matched control group was 4.64 ± 2.32 μmol/L. Results: Thirty-four BA patients underwent KP over a period of 2 years. The mean age of presentation was 2.7 months (range 1-4 months. The mean intraoperative PP was 21.3 ± 5.4 mmHg. The mean PP in patients aged 90 days was 18.53 ± 4.45 mmHg, 20.33 ± 3.07 mmHg, and 26.5 ± 5.01 mmHg, respectively. The mean PP in the patients who underwent successful KP was 16.75 ± 3.54 mmHg while for those who continued to have jaundice it was 23.94 ± 4.63 mmHg (P < 0.001. NO levels closely followed the PP as shown by the regression equation NO = 4.79 + 0.64 PP mmHg, R2 = 0.69. The mean NO level at presentation was 18.48 ± 4.17 μmol/L and at 1-month, 3-month, and 6-month follow-up was 11.94 ± 5.62 μmol/L, 10.79 ± 6.02 μmol/L, and 9.93 ± 6.53 μmol/L, respectively (P < 0.001. The difference in NO levels was also statistically significant between the patients who cleared jaundice and those with persisting jaundice. Conclusion: All BA patients had PHT at presentation. PHT worsens with age and has an adverse effect on outcome of KP. NO levels in blood closely follow PP and higher levels are associated with poor outcome.

  3. Portal pressure and blood nitric oxide levels as predictors of outcome in biliary atresia

    Science.gov (United States)

    Khanna, Vikram; Bhatnagar, Veereshwar; Agarwala, Sandeep; Srinivas, Maddur; Das, Nibhriti; Singh, Manoj Kumar

    2016-01-01

    Aim: To evaluate the incidence of portal hypertension (PHT) in biliary atresia (BA) patients and to monitor its progress after Kasai portoenterostomy (KP) by measuring nitric oxide (NO) levels in peripheral blood. Materials and Methods: A prospective cross-sectional study conducted over a period of 2 years. Intraoperative portal pressure (PP) and blood NO levels at presentation, 1-month, 3-month, and 6-month follow-up, were correlated with clinical and biochemical parameters in BA patients. The mean NO level in age-matched control group was 4.64 ± 2.32 μmol/L. Results: Thirty-four BA patients underwent KP over a period of 2 years. The mean age of presentation was 2.7 months (range 1-4 months). The mean intraoperative PP was 21.3 ± 5.4 mmHg. The mean PP in patients aged 90 days was 18.53 ± 4.45 mmHg, 20.33 ± 3.07 mmHg, and 26.5 ± 5.01 mmHg, respectively. The mean PP in the patients who underwent successful KP was 16.75 ± 3.54 mmHg while for those who continued to have jaundice it was 23.94 ± 4.63 mmHg (P < 0.001). NO levels closely followed the PP as shown by the regression equation NO = 4.79 + 0.64 PP mmHg, R2 = 0.69. The mean NO level at presentation was 18.48 ± 4.17 μmol/L and at 1-month, 3-month, and 6-month follow-up was 11.94 ± 5.62 μmol/L, 10.79 ± 6.02 μmol/L, and 9.93 ± 6.53 μmol/L, respectively (P < 0.001). The difference in NO levels was also statistically significant between the patients who cleared jaundice and those with persisting jaundice. Conclusion: All BA patients had PHT at presentation. PHT worsens with age and has an adverse effect on outcome of KP. NO levels in blood closely follow PP and higher levels are associated with poor outcome. PMID:27046973

  4. [Examination of the oral cavities of patients with cancer: clinical evaluation and indirect measurement of the nitric oxide level].

    Science.gov (United States)

    de Carvalho, Emilia Campos; Cárnio, Evelin Capellari; Khouri, Vivian Youssef; Guilherme, Caroline; dos Santos, Claudia Benedita; Pace, Mariangela Aparecida

    2013-02-01

    This observational study aimed to verify the association between the clinical state of the oral cavity (based on the Index of Decayed, Missing, and Filled Teeth and the Simplified Oral Hygiene Index) and the indirectly determined nitric oxide level in patients with oncologic and hematologic diseases. This study included 20 hospitalized patients who were in the evaluation phase prior to starting chemotherapy and who had been diagnosed with leukemia (35%), lymphoma (50%) or myeloma (15%). Fifty percent of these patients had normal oral health (no injury or trauma), and most had satisfactory (35%) or typical (35%) hygiene, but 30% had poor or very poor hygiene. The indirectly measured levels of nitric oxide ranged from 13.34 to 257. The nitric oxide level was not associated with other parameters, and there was great variability in its level. Further studies are necessary given the potential of using this indicator in the early detection of oral diseases.

  5. Unsaturated aldehydes as alkene equivalents in the Diels-Alder reaction

    DEFF Research Database (Denmark)

    Taarning, Esben; Madsen, Robert

    2008-01-01

    A one-pot procedure is described for using alpha,beta-unsaturated aldehydes as olefin equivalents in the Diels-Alder reaction. The method combines the normal electron demand cycloaddition with aldehyde dienophiles and the rhodium-catalyzed decarbonylation of aldehydes to afford cyclohexenes with ...

  6. Oleic acid-dependent modulation of Nitric oxide associated 1 protein levels regulates nitric oxide-mediated defense signaling in Arabidopsis

    Science.gov (United States)

    The conserved cellular metabolites nitric oxide (NO) and oleic acid (18:1) are well-known regulators of disease physiologies in diverse organism. We show that NO production in plants is regulated via 18:1. Reduction in 18:1 levels, via a genetic mutation in the 18:1-synthesizing gene SUPPRESSOR OF S...

  7. Nitric oxide level in seminal plasma of fertile and infertile males and its correlation with sperm parameters

    Directory of Open Access Journals (Sweden)

    Amiri I.

    2006-07-01

    Full Text Available Nitric oxide (NO is a free radical molecule, produced by most cells and tissues in the body. The effect of NO on cells is concentration dependent. Low concentration of NO is essential in biology and physiology of most of cells, but high amounts of NO is toxic and has detrimental effects on cells. The role of NO in biology of male and female genital systems is under investigation. In the present study, the nitric oxide concentration was measured in the seminal plasma of both fertile and infertile males and compared with spermatogram parameters. For this purpose, semen samples were collected from 45 patients and 70 healthy donors. After analysis of samples, the stable metabolites of nitric oxide (nitrite and nitrate were measured by Griess assay. The results indicated that the nitric oxide concentration in the seminal plasma of infertile males was significantly higher than controls. There was a significant negative correlation between the nitric oxide concentration and sperm motility and viability in infertile males. In conclusion, this study demonstrated that the level of nitric oxide in seminal plasma of infertile men was higher than that of fertile men. The increasing level of nitric oxide concentration in seminal plasma leads to the decrease in sperm motility and viability and affects fertility.

  8. EFFECT OF RICE STRAW AND NITRATE LEVELS IN SOIL SOLUTION ON NITROUS OXIDE EMISSION

    Directory of Open Access Journals (Sweden)

    André Carlos Cruz Copetti

    2015-04-01

    Full Text Available Among the greenhouse gases, nitrous oxide (N2O is considered important, in view of a global warming potential 296 times greater than that of carbon dioxide (CO2 and its dynamics strongly depend on the availability of C and mineral N in the soil. The understanding of the factors that define emissions is essential to develop mitigation strategies. This study evaluated the dynamics of N2O emissions after the application of different rice straw amounts and nitrate levels in soil solution. Pots containing soil treated with sodium nitrate rates (0, 50 and 100 g kg-1 of NO−3-N and rice straw levels (0, 5 and 10 Mg ha-1, i.e., nine treatments, were subjected to anaerobic conditions. The results showed that N2O emissions were increased by the addition of greater NO−3 amounts and reduced by large straw quantities applied to the soil. On the 1st day after flooding (DAF, significantly different N2O emissions were observed between the treatments with and without NO−3 addition, when straw had no significant influence on N2O levels. Emissions peaked on the 4th DAF in the treatments with highest NO−3-N addition. At this moment, straw application negatively affected N2O emissions, probably due to NO−3 immobilization. There were also alterations in other soil electrochemical characteristics, e.g., higher straw levels raised the Fe, Mn and dissolved C contents. These results indicate that a lowering of NO−3 concentration in the soil and the increase of straw incorporation can decrease N2O emissions.

  9. Evaluation of salivary nitric oxide level in children with early childhood caries

    Directory of Open Access Journals (Sweden)

    A R Senthil Eagappan

    2016-01-01

    Full Text Available Background: Nitric oxide (NO, a highly reactive radical, participates in the nonspecific natural defense mechanism of the oral cavity. The present study was attempted to evaluate the salivary NO levels in 4–5 year-old children with early childhood caries (ECC. The objective of the present study was to assess the salivary NO concentration in children with different caries activity. Materials and Methods: The study included 120 healthy 4–5 year-old children and they were equally divided into three groups based on decayed, missing, filled surfaces (dmfs score; forty caries-free children (control group, forty children with dmfs 1–5 (ECC group, and forty with dmfs ≥6 (severe ECC group. Saliva collected was measured for NO concentration by Griess reaction method. The obtained data were analyzed by ANOVA and Pearson's correlation coefficient. Results: The mean level of NO in the saliva of the control group was 51.2 ± 8.3457 and that of ECC and severe ECC were 47.1 ± 5.2614 and 33.625 ± 4.6942, respectively. The mean salivary NO concentration was significantly higher in healthy controls when compared to children with ECC and severe ECC. Moreover, a negative correlation (r = −0.6658 was observed between the salivary NO level and the mean dmfs, suggesting that as the salivary NO level decreases, the caries incidence increases. Conclusion: The obtained results support the antimicrobial activity of salivary NO and also suggest that an increase in NO production might contribute to lower the caries occurrence in children.

  10. Evaluation of salivary nitric oxide level in children with early childhood caries

    Science.gov (United States)

    Senthil Eagappan, AR; Rao, V. Arun Prasad; Sujatha, S.; Senthil, D.; Sathiyajeeva, J.; Rajaraman, G.

    2016-01-01

    Background: Nitric oxide (NO), a highly reactive radical, participates in the nonspecific natural defense mechanism of the oral cavity. The present study was attempted to evaluate the salivary NO levels in 4–5 year-old children with early childhood caries (ECC). The objective of the present study was to assess the salivary NO concentration in children with different caries activity. Materials and Methods: The study included 120 healthy 4.5 year-old children and they were equally divided into three groups based on decayed, missing, filled surfaces (dmfs) score; forty caries-free children (control group), forty children with dmfs 1.5 (ECC group), and forty with dmfs ⩾6 (severe ECC group). Saliva collected was measured for NO concentration by Griess reaction method. The obtained data were analyzed by ANOVA and Pearson's correlation coefficient. Results: The mean level of NO in the saliva of the control group was 51.2 ± 8.3457 and that of ECC and severe ECC were 47.1 ± 5.2614 and 33.625 ± 4.6942, respectively. The mean salivary NO concentration was significantly higher in healthy controls when compared to children with ECC and severe ECC. Moreover, a negative correlation (r = −0.6658) was observed between the salivary NO level and the mean dmfs, suggesting that as the salivary NO level decreases, the caries incidence increases. Conclusion: The obtained results support the antimicrobial activity of salivary NO and also suggest that an increase in NO production might contribute to lower the caries occurrence in children. PMID:27605992

  11. Biogenic isoprene and implications for oxidant levels in Beijing during the 2008 Olympic Games

    Science.gov (United States)

    Chang, Chih-Chung; Shao, Min; Chou, Charles C. K.; Liu, Shaw-Chen; Zhu, Tong; Lee, Kun-Zhang; Lai, Cheng-Hsun; Lin, Po-Hsiung; Wang*, Jia-Lin

    2014-05-01

    As the host of the 2008 Summer Olympic Games, Beijing implemented a series of stringent, short-term air quality control measures to reduce the emissions of anthropogenic air pollutants. Large reductions in the daily average concentrations of primary pollutants, e.g., non-methane hydrocarbons (NMHCs) and nitrogen oxides (NOx) of approximately 50% were observed at the air quality observatory of Peking University. Nevertheless, high levels of ozone were present during the control period. Although anthropogenic precursors were greatly reduced, the meteorological conditions in summer, including high temperature and light flux, are conducive to the production of large amounts of biogenic isoprene, which is extremely reactive. The diurnal pattern of isoprene showed daily maximum mixing ratios of 0.83 ppbv at noon and a minimum at night, reflecting its primarily biogenic properties. Using the ratio of isoprene to vehicle exhaust tracers, approximately 92% of the daytime isoprene was estimated from biogenic sources, and only 8% was attributed to vehicular emissions. In terms of OH reactivity and the ozone formation potential (OFP), biogenic isoprene with its midday surge can contribute approximately 20% of the total OFPs and 40-50% of the total OH reactivities of the 65 measured NMHCs during the midday hours. The discrepancy between decreased precursor levels and the observed high ozone was most likely caused by a combination of many factors. The changes in the partition among the components of oxidation products (O3, NO2 and NOz) and the contribution of air pollutants from regional sources outside Beijing should be two primary reasons. Furthermore, the influences of biogenic isoprene as well as the non-linearity of O3-VOC-NOx chemistry are other major concerns that can reduce the effectiveness of the control measures for decreasing ozone formation. Although anthropogenic precursors were greatly reduced during the Olympic Games, the presence of sufficient biogenic isoprene

  12. Stoichiometry of mitochondrial H+ translocation coupled to succinate oxidation at level flow.

    Science.gov (United States)

    Costa, L E; Reynafarje, B; Lehninger, A L

    1984-04-25

    The mechanistic stoichiometry of vectorial H+ translocation coupled to succinate oxidation by rat liver mitochondria in the presence of a permeant cation has been determined under level flow conditions with a membraneless fast responding O2 electrode kinetically matched with a glass pH electrode. The reactions were initiated by rapid injection of O2 into the anaerobically preincubated test system under conditions in which interfering H+ backflow was minimized. The rates of O2 uptake and H+ ejection, obtained from computer-fitted regression lines, were monotonic and first order over 75% of the course of O2 consumption. Extrapolation of the observed rates to zero time, at which zero delta mu H+ and thus level flow prevails, yielded vectorial H+/O flow ratios above 7 and closely approaching 8. The mitochondria undergo no irreversible change and give identical H+/O ratios on repeated tests. In a further refinement, the lower and upper limits of the mechanistic H+/O ratio were determined to be 7.55 and 8.56, respectively, from plots of the rates of O2 uptake versus H+ ejection at increasing malonate and increasing valinomycin concentrations, respectively. It is therefore concluded that the mechanistic H+/O ratio for energy-conserving sites 2 + 3 is 8, in confirmation of earlier measurements. KCl concentration is critical for maximal observed H+/O ratios. Optimum conditions and possible errors in determination of mechanistic H+/O translocation ratios are discussed.

  13. Low levels of graphene and graphene oxide inhibit cellular xenobiotic defense system mediated by efflux transporters.

    Science.gov (United States)

    Liu, Su; Jiang, Wei; Wu, Bing; Yu, Jing; Yu, Haiyan; Zhang, Xu-Xiang; Torres-Duarte, Cristina; Cherr, Gary N

    2016-06-01

    Low levels of graphene and graphene oxide (GO) are considered to be environmentally safe. In this study, we analyzed the potential effects of graphene and GO at relatively low concentrations on cellular xenobiotic defense system mediated by efflux transporters. The results showed that graphene (<0.5 μg/mL) and GO (<20 μg/mL) did not decrease cell viability, generate reactive oxygen species, or disrupt mitochondrial function. However, graphene and GO at the nontoxic concentrations could increase calcein-AM (CAM, an indicator of membrane ATP-binding cassette (ABC) transporter) activity) accumulation, indicating inhibition of ABC transporters' efflux capabilities. This inhibition was observed even at 0.005 μg/mL graphene and 0.05 μg/mL GO, which are 100 times and 400 times lower than their lowest toxic concentration from cytotoxicity experiments, respectively. The inhibition of ABC transporters significantly increased the toxicity of paraquat and arsenic, known substrates of ABC transporters. The inhibition of ABC transporters was found to be based on graphene and GO damaging the plasma membrane structure and fluidity, thus altering functions of transmembrane ABC transporters. This study demonstrates that low levels of graphene and GO are not environmentally safe since they can significantly make cell more susceptible to other xenobiotics, and this chemosensitizing activity should be considered in the risk assessment of graphene and GO. PMID:26554512

  14. Stoichiometry of mitochondrial H+ translocation coupled to succinate oxidation at level flow.

    Science.gov (United States)

    Costa, L E; Reynafarje, B; Lehninger, A L

    1984-04-25

    The mechanistic stoichiometry of vectorial H+ translocation coupled to succinate oxidation by rat liver mitochondria in the presence of a permeant cation has been determined under level flow conditions with a membraneless fast responding O2 electrode kinetically matched with a glass pH electrode. The reactions were initiated by rapid injection of O2 into the anaerobically preincubated test system under conditions in which interfering H+ backflow was minimized. The rates of O2 uptake and H+ ejection, obtained from computer-fitted regression lines, were monotonic and first order over 75% of the course of O2 consumption. Extrapolation of the observed rates to zero time, at which zero delta mu H+ and thus level flow prevails, yielded vectorial H+/O flow ratios above 7 and closely approaching 8. The mitochondria undergo no irreversible change and give identical H+/O ratios on repeated tests. In a further refinement, the lower and upper limits of the mechanistic H+/O ratio were determined to be 7.55 and 8.56, respectively, from plots of the rates of O2 uptake versus H+ ejection at increasing malonate and increasing valinomycin concentrations, respectively. It is therefore concluded that the mechanistic H+/O ratio for energy-conserving sites 2 + 3 is 8, in confirmation of earlier measurements. KCl concentration is critical for maximal observed H+/O ratios. Optimum conditions and possible errors in determination of mechanistic H+/O translocation ratios are discussed. PMID:6232269

  15. Effects of composite restorations on nitric oxide and uric acid levels in saliva

    Directory of Open Access Journals (Sweden)

    Nilgun Akgul

    2015-01-01

    Full Text Available Background and Aims: Dental materials that are used in dentistry should be harmless to oral tissues, and should, therefore, not contain any leachable toxic and diffusible substances capable of causing side effects. This study was intended to investigate the effects on salivary nitric oxide (NO and uric acid (UA levels after application of dental composite filling materials to healthy volunteers. Materials and Methods: A total of 52 individuals (32 female and 20 male participated in the study. Filtek Z250 composite filling material (3M ESPE, St Paul, MN, USA was applied to healthy volunteers. Saliva samples were collected before restoration (baseline and 1 h, 1-day, 7 days, and 30 days after restoration. NO concentrations were measured using the Griess reaction method, and UA was measured using an enzymatic method. Data were analyzed using repeated measures ANOVA and the Bonferroni post-hoc test (α =5%. Results: NO values increased statistically significant after 7 days (P 0.05. There was no correlation between NO and UA levels in saliva (P > 0.05. Conclusion: Composite resins activated the antioxidant system in saliva. However, further studies are now needed to confirm our findings and to permit a definitive conclusion.

  16. Increased levels of proinflammatory cytokines and nitric oxide metabolites in neuropsychiatric lupus erythematosus

    Science.gov (United States)

    Svenungsson, E; Andersson, M; Brundin, L; van Vollenhoven, R; Khademi, M; Tarkowski, A; Greitz, D; Dahlstrom, M; Lundberg, I; Klareskog, L; Olsson, T

    2001-01-01

    OBJECTIVE—To investigate systemic and intrathecal production of proinflammatory cytokines in relation to cerebrospinal fluid (CSF) nitric oxide (NO) release in patients with neuropsychiatric lupus erythematosus (NPLE).
METHODS—Thirty patients with NPLE rated as mild, moderate, or severe were studied and CSF was obtained from 21 of these. Cytokine mRNA expressing cells were detected by in situ hybridisation. Soluble cytokines were assessed by enzyme linked immunosorbent assay (ELISA). Nitrite and nitrate were determined by capillary electrophoresis.
RESULTS—Patients with NPLE had high numbers of lymphocytes expressing mRNA for tumour necrosis factor α (TNFα), interferon γ, and interleukin 10 in blood. The number of peripheral blood TNFα mRNA positive cells correlated strongly with the level of NO metabolites in the CSF (r2=0.69). Both the number of peripheral blood mononuclear cells expressing mRNA for TNFα as well as the CSF level of NO metabolites correlated with NPLE disease severity.
CONCLUSION—These data suggest that increased peripheral production of proinflammatory cytokines such as TNFα may contribute both to an increased production of NO in the central nervous system and to generation of clinical NPLE. The data also support the possibility that measurements of NO metabolites in CSF may be of value in the diagnosis of neurological symptoms related to SLE.

 PMID:11247868

  17. Lymphocyte Oxidative Stress/Genotoxic Effects Are Related to Serum IgG and IgA Levels in Coke Oven Workers

    OpenAIRE

    Meili Gao; Yongfei Li; Aqun Zheng; Xiaochang Xue; Lan Chen; Yu Kong

    2014-01-01

    We investigated oxidative stress/genotoxic effects levels, immunoglobulin levels, polycyclic aromatic hydrocarbons (PAHs) levels exposed in 126 coke oven workers and in 78 control subjects, and evaluated the association between oxidative stress/genotoxic effects levels and immunoglobulin levels. Significant differences were observed in biomarkers, including 1-hydroxypyrene levels, employment time, percentages of alcohol drinkers, MDA, 8-OHdG levels, CTL levels and CTM, MN, CA frequency, and I...

  18. Impact of Added Encapsulated Phosphate Level on Lipid Oxidation Inhibition during the Storage of Cooked Ground Meat.

    Science.gov (United States)

    Kılıç, B; Şimşek, A; Claus, J R; Atılgan, E; Bilecen, D

    2016-02-01

    The effect of levels (0.1%, 0.2%, 0.3%, 0.4%, 0.5%) of added encapsulated (e) phosphate (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation inhibition during storage (0, 1, and 7 d) of ground meat (chicken, beef) was evaluated. The use of eSTP and eSPP resulted in lower and higher cooking loss (CL) compared to eHMP, respectively (P level (PL) enhanced the impact of phosphates on CL in both chicken and beef samples (P level of OP determined in both chicken and beef samples increased (P strategy to inhibit lipid oxidation for the meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by increasing PL. PMID:26753985

  19. Effects of Ischemic Postconditioning on the Hemodynamic Parameters and Heart Nitric Oxide Levels of Hypothyroid Rats

    Energy Technology Data Exchange (ETDEWEB)

    Jeddi, Sajad; Zaman, Jalal; Ghasemi, Asghar, E-mail: ghasemi@endocrine.ac.ir [Endocrine Physiology Research Center - Research Institute for Endocrine Sciences - Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Endocrine Research Center - Research Institute for Endocrine Sciences - Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2015-02-15

    Ischemic postconditioning (IPost) is a method of protecting the heart against ischemia-reperfusion (IR) injury. However, the effectiveness of IPost in cases of ischemic heart disease accompanied by co-morbidities such as hypothyroidism remains unclear. The aim of this study was to determine the effect of IPost on myocardial IR injury in hypothyroid male rats. Propylthiouracil in drinking water (500 mg/L) was administered to male rats for 21 days to induce hypothyroidism. The hearts from control and hypothyroid rats were perfused in a Langendorff apparatus and exposed to 30 min of global ischemia, followed by 120 min of reperfusion. IPost was induced immediately following ischemia. Hypothyroidism and IPost significantly improved the left ventricular developed pressure (LVDP) and peak rates of positive and negative changes in left ventricular pressure (±dp/dt) during reperfusion in control rats (p < 0.05). However, IPost had no add-on effect on the recovery of LVDP and ±dp/dt in hypothyroid rats. Furthermore, hypothyroidism significantly decreased the basal NO metabolite (NO{sub x}) levels of the serum (72.5 ± 4.2 vs. 102.8 ± 3.7 μmol/L; p < 0.05) and heart (7.9 ± 1.6 vs. 18.8 ± 3.2 μmol/L; p < 0.05). Heart NO{sub x} concentration in the hypothyroid groups did not change after IR and IPost, whereas these were significantly (p < 0.05) higher and lower after IR and IPost, respectively, in the control groups. Hypothyroidism protects the heart from IR injury, which may be due to a decrease in basal nitric oxide (NO) levels in the serum and heart and a decrease in NO after IR. IPost did not decrease the NO level and did not provide further cardioprotection in the hypothyroid group.

  20. Effects of Ischemic Postconditioning on the Hemodynamic Parameters and Heart Nitric Oxide Levels of Hypothyroid Rats

    International Nuclear Information System (INIS)

    Ischemic postconditioning (IPost) is a method of protecting the heart against ischemia-reperfusion (IR) injury. However, the effectiveness of IPost in cases of ischemic heart disease accompanied by co-morbidities such as hypothyroidism remains unclear. The aim of this study was to determine the effect of IPost on myocardial IR injury in hypothyroid male rats. Propylthiouracil in drinking water (500 mg/L) was administered to male rats for 21 days to induce hypothyroidism. The hearts from control and hypothyroid rats were perfused in a Langendorff apparatus and exposed to 30 min of global ischemia, followed by 120 min of reperfusion. IPost was induced immediately following ischemia. Hypothyroidism and IPost significantly improved the left ventricular developed pressure (LVDP) and peak rates of positive and negative changes in left ventricular pressure (±dp/dt) during reperfusion in control rats (p < 0.05). However, IPost had no add-on effect on the recovery of LVDP and ±dp/dt in hypothyroid rats. Furthermore, hypothyroidism significantly decreased the basal NO metabolite (NOx) levels of the serum (72.5 ± 4.2 vs. 102.8 ± 3.7 μmol/L; p < 0.05) and heart (7.9 ± 1.6 vs. 18.8 ± 3.2 μmol/L; p < 0.05). Heart NOx concentration in the hypothyroid groups did not change after IR and IPost, whereas these were significantly (p < 0.05) higher and lower after IR and IPost, respectively, in the control groups. Hypothyroidism protects the heart from IR injury, which may be due to a decrease in basal nitric oxide (NO) levels in the serum and heart and a decrease in NO after IR. IPost did not decrease the NO level and did not provide further cardioprotection in the hypothyroid group

  1. Influence of nutrients on oxidation of low level methane by mixed methanotrophic consortia.

    Science.gov (United States)

    Karthikeyan, Obulisamy Parthiba; Chidambarampadmavathy, Karthigeyan; Nadarajan, Saravanan; Heimann, Kirsten

    2016-03-01

    Low-level methane emissions from coal mine ventilation air (CMV-CH4; i.e., 1 % CH4) can significantly contribute to global climate change, and therefore, treatment is important to reduce impacts. To investigate CMV-CH4 abatement potential, five different mixed methanotrohic consortia (MMCs) were established from soil/sediment sources, i.e., landfill top cover soil, bio-solid compost, vegetated humus soil, estuarine and marine sediments. Enrichment conditions for MMCs were as follows: nitrate mineral salt (NMS) medium, pH ~ 6.8; 25 °C; 20-25 % CH4; agitation 200 rpm; and culture period 20 days, in mini-bench-top bioreactors. The enriched cultures were supplemented with extra carbon (methanol 0.5-1.5 %, formate 5-15 mM, and acetate 5-15 mM), nitrogen (nitrate 0.5-1.5 g L(-1), ammonium 0.1-0.5 g L(-1), or urea: 0.1-0.5 g L(-1)), and trace elements (copper 1-5 μM, iron 1-5 μM, and zinc 1-5 μM) in different batch experiments to improve low-level CH4 abatement. Average CH4 oxidation capacities (MOCs) of MMCs varied between 1.712 ± 0.032 and 1.963 ± 0.057 mg g(-1)DWbiomass h(-1). Addition of formate improved the MOCs of MMCs, but the dose-response varied for different MMCs. Acetate, nitrate and copper had no significant effect on MOCs, while addition of methanol, ammonium, urea, iron and zinc impacted negatively. Overall, MMCs enriched from marine sediments and landfill top cover soil showed high MOCs which were largely resilient to nutrient supplementation, suggesting a strong potential for biofilter development for industrial low-level CH4 abatement, such as those present in CMV. PMID:26867685

  2. Effects of Ischemic Postconditioning on the Hemodynamic Parameters and Heart Nitric Oxide Levels of Hypothyroid Rats

    Directory of Open Access Journals (Sweden)

    Sajad Jeddi

    2015-02-01

    Full Text Available Background: Ischemic postconditioning (IPost is a method of protecting the heart against ischemia-reperfusion (IR injury. However, the effectiveness of IPost in cases of ischemic heart disease accompanied by co-morbidities such as hypothyroidism remains unclear. Objective: The aim of this study was to determine the effect of IPost on myocardial IR injury in hypothyroid male rats. Methods: Propylthiouracil in drinking water (500 mg/L was administered to male rats for 21 days to induce hypothyroidism. The hearts from control and hypothyroid rats were perfused in a Langendorff apparatus and exposed to 30 min of global ischemia, followed by 120 min of reperfusion. IPost was induced immediately following ischemia. Results: Hypothyroidism and IPost significantly improved the left ventricular developed pressure (LVDP and peak rates of positive and negative changes in left ventricular pressure (±dp/dt during reperfusion in control rats (p < 0.05. However, IPost had no add-on effect on the recovery of LVDP and ±dp/dt in hypothyroid rats. Furthermore, hypothyroidism significantly decreased the basal NO metabolite (NOx levels of the serum (72.5 ± 4.2 vs. 102.8 ± 3.7 μmol/L; p < 0.05 and heart (7.9 ± 1.6 vs. 18.8 ± 3.2 μmol/L; p < 0.05. Heart NOx concentration in the hypothyroid groups did not change after IR and IPost, whereas these were significantly (p < 0.05 higher and lower after IR and IPost, respectively, in the control groups. Conclusion: Hypothyroidism protects the heart from IR injury, which may be due to a decrease in basal nitric oxide (NO levels in the serum and heart and a decrease in NO after IR. IPost did not decrease the NO level and did not provide further cardioprotection in the hypothyroid group.

  3. Mercury levels assessment and its relationship with oxidative stress biomarkers in children from three localities in Yucatan, Mexico.

    Science.gov (United States)

    Rangel-Méndez, Jorge A; Arcega-Cabrera, Flor E; Fargher, Lane F; Moo-Puc, Rosa E

    2016-02-01

    Mercury (Hg) is a global pollutant that is released into the environment from geologic and anthropogenic sources. Once it enters an organism, it generates several toxicity mechanisms and oxidative stress has been proposed as the main one. Metal susceptibility is greater in children, which is a result of their physiology and behavior. In Yucatan, Mexico, burning of unregulated garbage dumps and household trash, ingestion of top marine predators, and pottery manufacturing are among the conditions that could promote Hg exposure. However, for Yucatan, there are no published studies that report Hg levels and associated oxidative stress status in children. Therefore, this study aimed to assess Hg levels in blood and urine and oxidative stress biomarkers levels in a sample of 107 healthy children from three localities in Yucatan, Mexico, as well as investigate the relationship between these parameters. Hg was detected in 11 (10.28%) of blood samples and 38 (35.51%) of urine samples collected from the participating children. Fourteen subjects showed Hg above recommended levels. The oxidative stress biomarkers were slightly elevated in comparison with other studies and were statistically different between the sampling sites. No linear correlation between Hg levels and oxidative stress biomarkers was found. Nevertheless, exploratory univariate and multivariate analysis showed non-linear relations among the measured variables. Globally, the study provides, for the first time, information regarding Hg levels and their relationship with oxidative stress biomarkers in a juvenile population from Mexico's southeast (Yucatan) region. In agreement with worldwide concern about Hg, this study should stimulate studies on metal monitoring in humans (especially children) among scientists working in Mexico, the establishment of polices for its regulation, and the reduction of human health risks.

  4. Mercury levels assessment and its relationship with oxidative stress biomarkers in children from three localities in Yucatan, Mexico.

    Science.gov (United States)

    Rangel-Méndez, Jorge A; Arcega-Cabrera, Flor E; Fargher, Lane F; Moo-Puc, Rosa E

    2016-02-01

    Mercury (Hg) is a global pollutant that is released into the environment from geologic and anthropogenic sources. Once it enters an organism, it generates several toxicity mechanisms and oxidative stress has been proposed as the main one. Metal susceptibility is greater in children, which is a result of their physiology and behavior. In Yucatan, Mexico, burning of unregulated garbage dumps and household trash, ingestion of top marine predators, and pottery manufacturing are among the conditions that could promote Hg exposure. However, for Yucatan, there are no published studies that report Hg levels and associated oxidative stress status in children. Therefore, this study aimed to assess Hg levels in blood and urine and oxidative stress biomarkers levels in a sample of 107 healthy children from three localities in Yucatan, Mexico, as well as investigate the relationship between these parameters. Hg was detected in 11 (10.28%) of blood samples and 38 (35.51%) of urine samples collected from the participating children. Fourteen subjects showed Hg above recommended levels. The oxidative stress biomarkers were slightly elevated in comparison with other studies and were statistically different between the sampling sites. No linear correlation between Hg levels and oxidative stress biomarkers was found. Nevertheless, exploratory univariate and multivariate analysis showed non-linear relations among the measured variables. Globally, the study provides, for the first time, information regarding Hg levels and their relationship with oxidative stress biomarkers in a juvenile population from Mexico's southeast (Yucatan) region. In agreement with worldwide concern about Hg, this study should stimulate studies on metal monitoring in humans (especially children) among scientists working in Mexico, the establishment of polices for its regulation, and the reduction of human health risks. PMID:26580741

  5. Biogenic isoprene and implications for oxidant levels in Beijing during the 2008 Olympic Games

    Directory of Open Access Journals (Sweden)

    C.-C. Chang

    2013-10-01

    Full Text Available As the host of the 2008 Summer Olympic Games, Beijing implemented a series of stringent, short-term air quality control measures to reduce the emissions of anthropogenic air pollutants. Large reductions in the daily average concentrations of primary pollutants, e.g., non-methane hydrocarbons (NMHCs and nitrogen oxides (NOx of approximately 50% were observed at the air quality observatory of Peking University. Nevertheless, high levels of ozone were present during the control period. Although anthropogenic precursors were greatly reduced, the meteorological conditions in summer, including high temperature and light flux, are conducive to the production of large amounts of biogenic isoprene, which is extremely reactive. The diurnal pattern of isoprene showed daily maximum mixing ratios of 0.83 ppbv at noon and a minimum at night, reflecting its primarily biogenic properties. Using the ratio of isoprene to vehicle exhaust tracers, approximately 92% of the daytime isoprene was estimated from biogenic sources, and only 8% was attributed to vehicular emissions. In terms of OH reactivity and the ozone formation potential (OFP, biogenic isoprene with its midday surge can contribute approximately 20% of the total OFPs and 40–50% of the total OH reactivities of the 65 measured NMHCs during the midday hours. The discrepancy between decreased precursor levels and the observed high ozone was most likely caused by a combination of many factors. The changes in the partition among the components of oxidation products (O3, NO2 and NOz and the contribution of air pollutants from regional sources outside Beijing should be two primary reasons. Furthermore, the influences of biogenic isoprene as well as the non-linearity of O3-VOC-NOx chemistry are other major concerns that can reduce the effectiveness of the control measures for decreasing ozone formation. Although anthropogenic precursors were greatly reduced during the Olympic Games, sufficient biogenic

  6. The relationship between cytokine level and nitric oxide content in aqueous humor after intraocular lens implantation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: To investigate the relationship between cytokine level and nitric oxide (NO) content in aqueous humor after intraocular lens implantation. METHODS: All New Zealand rabbits were divided randomly into three groups: (1) control group, (2) extracapsular cataract extraction group (ECCE), (3) extracapsular cataract extraction and posterior chamber intraocular lens implantation group (ECCE+IOL). The inflammation of all experimental rabbit eyes, including cornea edema and anterior chamber exudation were observed via zoom-photo slitlamp microscope 1,3,7,14,30 d postoperation. Meanwhile, aqueous humor was drawn for white blood cell (WBC) counting and classifying, and for NO-2/NO-3 and cytokine assay, including interleukin-2(IL-2), tumour necrosis factor-α(TNF-α). Statistics were taken by SPSS softwear. RESULTS: (1) Total WBC in aqueous humor were higher and anterior chamber exudation were more severe in ECCE+IOL group than that in ECCE group and control group. (2) The level of IL-2 and TNF-α and the content of NO-2/NO-3 in aqueous humor of ECCE+IOL group were higher than that in ECCE group and control group 1-14 d postoperation respectively, and it increased to peak value at 3-7 d postoperation and decreased gradually after two weeks postoperation. (3) The change regularity of IL-2, TNF-α and NO-2/NO-3 in each group were basically similar, i.e. when the level of cytokine (IL-2 and TNF-α) was normal, the content of NO-2/NO-3 was normal too, when the level of cytokine (IL-2 and TNF-α) increased, the content of NO-2/NO-3 increased too. CONCLUSION: The intraocular inflammation after ECCE+IOL was more severe than that after simple ECCE. NO, IL-2 and TNF-α play an important role in intraocular inflammation after intraocular lens implantation. The changes of IL-2 and TNF-α level was closely related with NO content in aqueous humor.

  7. Effects of Various Levels of Oxidized Oil on Performance, Egg Quality and Some Blood Metabolites in Laying Hens

    Directory of Open Access Journals (Sweden)

    AA Saki

    2016-06-01

    Full Text Available The influence of dietary oxidized oil was studied on laying hen performance, egg quality and blood metabolites.  Experiment was conducted on 160 laying hens (Hy-Line W-36, 54-61 wk of age in a completely randomized design with five treatments and four replicated cages containing eight birds per cage. Dietary treatments replaced fresh soybean oil in the control diet (3% fresh soybean oil, 15.25% crude protein, and 2858 Kcal/kg metabolizable energy with 0, 25, 50, 75 and 100% oxidized oil. Egg production and egg weight were recorded daily and feed intake, feed conversion ratio, and egg mass were calculated weekly. Egg quality traits were recorded on a biweekly basis. Hen’s body weight was measured individually at the beginning and end of the experiment. Serum metabolites were determined at the end of the experiment. There was a significant difference between diets with different oxidized oil levels in egg weight, egg mass, Egg production, and feed conversion ratio (P < 0.05. Feed intake was not affected by dietary treatments. There was no significant difference between oxidized oil levels on blood serum triglyceride, total cholesterol, high-density lipoprotein, low-density lipoprotein and very low-density lipoprotein. Malondialdehyde of the liver was not affected by oxidized oils. The results of this study have clearly demonstrated that maximum 25% oxidized oil could be replaced by fresh oil in the diets without any adverse effect on the performance of laying hens.

  8. Lipid Peroxidation and Nitric Oxide Levels in Male Smokers' Spermatozoa and their Relation with Sperm Motility

    OpenAIRE

    Ghaffari, Mohammad Ali; Rostami, Morad

    2012-01-01

    Background Nitric oxide (NO) is synthesized from L-arginine by a family of enzymes known as nitric oxide synthases. Low concentrations of NO is essential in biology and physiology of spermatozoa, but high amounts of NO is toxic and has negative effects on sperm functions. Moreover, sperm membrane contains high concentrations of polyunsaturated fatty acids that are highly susceptible to oxidative damage that interferes with fertilization ability. Therefore, we investigated the correlation betw...

  9. Low levels of lipid oxidation radically increase the passive permeability of lipid bilayers.

    Science.gov (United States)

    Runas, Kristina A; Malmstadt, Noah

    2015-01-21

    Oxidation of unsaturated lipids in cellular membranes has been shown to cause severe membrane damage and potentially cell death. The presence of oxidized lipid species in the membrane is known to cause changes in membrane properties, such as decreased fluidity. This study uses giant unilamellar vesicles (GUVs) to measure passive transport across membranes containing defined concentrations of oxidized lipid species. GUVs consisting of a saturated phospholipid, an unsaturated phospholipid, and cholesterol were used as model membranes. By replacing defined amounts of the unsaturated lipid with a corresponding oxidized product, the oxidation process could be mimicked, yielding vesicles of varying oxidized lipid concentration. Oxidized lipid concentration was varied from 0 mol% to 18 mol% of the total lipid concentration. Passive transport of PEG12-NBD, an uncharged fluorescent molecule, was measured using a microfluidic trap to capture the GUVs and spinning disk confocal microscopy (SDCM) to track the transport of a fluorescent species in the equatorial plane of each GUV. Membrane permeability was determined by fitting the resulting concentration profiles to a finite difference model of diffusion and permeation around and through the membrane. Experiments showed three permeability regimes. Without oxidation, transport was slow, with a measured permeability on the order of 1.5 × 10(-6) cm s(-1). At 2.5-10% oxidized species permeation was fast (1.5 × 10(-5) cm s(-1)). Above 12.5% oxidized species, the bilayer was disrupted by the formation of pore defects. As passive transport is an important mechanism for drug delivery, understanding the relationship between oxidation and permeation could provide insight into the pharmaceutical characteristics of tissues with oxidative damage. PMID:25415555

  10. Effects of aerosolized ketamine on the level of nitric oxide and nitric oxide synthetase in the lung tissue of rat with asthma

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To explore the effects of aerosolized ketamine on the level of nitric oxide and nitric oxide synthetase in the lung tissue in rat asthma model. Methods: Forty SD rats were randomly assigned to five groups: control group (group N), asthma model group (group A), two pretreated groups of different concentrations of ketamine (group K1, K2)and dexamethasone group(group D) with eight rats in each group. The rats in group A were sensitized by injection of ovalbumin (OA) together with aluminum hydroxide and bordetella pertussis as adjuvants. Two weeks after the sensitization, aerosolized OA was used to cause asthma. The rats in group K1 and K2 were sensitized with OA as group A , and then exposed to aerosol of ketamine , with the concentration of 25 g/L and 50 g/L respectively. Before using aerosolized OA, the rats in group D were exposed to aerosol of 0.01% dexamethasone . The level of NO2-/NO3- in lung tissues, inducible nitric oxide synthetase(iNOS) and constitute nitric oxide synthetase(cNOS) was measured in all groups. Results: The level of NO2-/NO3- and the activity of iNOS in lung tissues in group A were signiticantly higher than those in the other groups. The iNOS activity and the level of NO2-/NO3- in lung tissues were highly positively correlated. Conclusion: NO can induce airway hyperreactivity that may worsen asthma. Aerosolized ketamine can decrease the iNOS expression and reduce the level of NO in the lung tissue in rat asthma model.

  11. Site-directed mutagenesis of aldehyde dehydrogenase-2 suggests three distinct pathways of nitroglycerin biotransformation.

    Science.gov (United States)

    Wenzl, M Verena; Beretta, Matteo; Griesberger, Martina; Russwurm, Michael; Koesling, Doris; Schmidt, Kurt; Mayer, Bernd; Gorren, Antonius C F

    2011-08-01

    To elucidate the mechanism underlying reduction of nitroglycerin (GTN) to nitric oxide (NO) by mitochondrial aldehyde dehydrogenase (ALDH2), we generated mutants of the enzyme lacking the cysteines adjacent to reactive Cys302 (C301S and C303S), the glutamate that participates as a general base in aldehyde oxidation (E268Q) or combinations of these residues. The mutants were characterized regarding acetaldehyde dehydrogenation, GTN-triggered enzyme inactivation, GTN denitration, NO formation, and soluble guanylate cyclase activation. Lack of the cysteines did not affect dehydrogenase activity but impeded GTN denitration, aggravated GTN-induced enzyme inactivation, and increased NO formation. A triple mutant lacking the cysteines and Glu268 catalyzed sustained formation of superstoichiometric amounts of NO and exhibited slower rates of inactivation. These results suggest three alternative pathways for the reaction of ALDH2 with GTN, all involving formation of a thionitrate/sulfenyl nitrite intermediate at Cys302 as the initial step. In the first pathway, which predominates in the wild-type enzyme and reflects clearance-based GTN denitration, the thionitrate apparently reacts with one of the adjacent cysteine residues to yield nitrite and a protein disulfide. The predominant reaction catalyzed by the single and double cysteine mutants requires Glu268 and results in irreversible enzyme inactivation. Finally, combined lack of the cysteines and Glu268 shifts the reaction toward formation of the free NO radical, presumably through homolytic cleavage of the sulfenyl nitrite intermediate. Although the latter reaction accounts for less than 10% of total turnover of GTN metabolism catalyzed by wild-type ALDH2, it is most likely essential for vascular GTN bioactivation.

  12. Influence of bismuth oxide concentration on the pH level and biocompatibility of white Portland cement

    Directory of Open Access Journals (Sweden)

    Marina Angélica MARCIANO

    2014-07-01

    Full Text Available Objectives: To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement. Material and Methods: White Portland cement (WPC was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6. The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p0.05. For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05. The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (p<0.05. Conclusions: The addition of bismuth oxide into Portland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated.

  13. Molecular-Level Processes Governing the Interaction of Contaminants with Iron and Manganese Oxides - Final Report; FINAL

    International Nuclear Information System (INIS)

    Many of the inorganic and organic contaminants present in sediments at DOE sites can be altered or destroyed by reduction and oxidation (redox) reactions occurring at mineral surfaces. A fundamental understanding of such redox processes provided by molecular-level studies on structurally and compositionally well-defined mineral surfaces will lead to: (i) improved models of contaminant fate and transport in geochemical systems, and (ii) optimized manipulation of these processes for remediation purposes. To contribute to this understanding, we will study, both experimentally and theoretically, redox processes involving three important contaminants - chromate ion, carbon tetrachloride, and trichloroethene TCE, on the following iron and manganese oxides - hematite, magnetite, maghemite, and pyrolusite. These oxides and their hydroxylated analogs commonly occur as coatings on minerals or as interfaces in the subsurface environment. Single-crystal surfaces of these oxides will be synthesized in carefully controlled fashion by molecular beam epitaxy. These surfaces, as well as high surface are powdered samples of these oxides, will be used in spectroscopic and kinetic experiments in both aqueous and gas phases. Our goal is to identify products and to determine the kinetics and mechanisms of surface-catalyzed redox reaction of Cr(VI) and CR(III), and the reductive dechlorination of carbon tetrachloride and TCE. The combination of theory and experiment will provide the base information needed to scale from the molecular level to the microscopic grain level minerals

  14. Exhaled nitric oxide and urinary EPX levels in infants: a pilot study

    Directory of Open Access Journals (Sweden)

    Olin Anna-Carin

    2011-05-01

    Full Text Available Abstract Background Objective markers of early airway inflammation in infants are not established but are of great interest in a scientific setting. Exhaled nitric oxide (FeNO and urinary eosinophilic protein X (uEPX are a two such interesting markers. Objective To investigate the feasibility of measuring FeNO and uEPX in infants and their mothers and to determine if any relations between these two variables and environmental factors can be seen in a small sample size. This was conducted as a pilot study for the ongoing Swedish Environmental Longitudinal Mother and child Asthma and allergy study (SELMA. Methods Consecutive infants between two and six months old and their mothers at children's health care centres were invited, and 110 mother-infant pairs participated. FeNO and uEPX were analysed in both mothers and infants. FeNO was analyzed in the mothers online by the use of the handheld Niox Mino device and in the infants offline from exhaled air sampled during tidal breathing. A 33-question multiple-choice questionnaire that dealt with symptoms of allergic disease, heredity, and housing characteristics was used. Results FeNO levels were reduced in infants with a history of upper respiratory symptoms during the previous two weeks (p Conclusion The use of uEPX as a marker of early inflammation was not supported. FeNO levels in infants were associated to windowpane condensation. Measuring FeNO by the present method may be an interesting way of evaluating early airway inflammation. In a major population study, however, the method is difficult to use, for practical reasons.

  15. An efficient and versatile synthesis of aromatic nitriles from aldehydes

    Institute of Scientific and Technical Information of China (English)

    Maryam Hajjami; Arash Ghorbani-Choghamarani; Mohammad Ali Zolfigol; Fatemeh Gholamian

    2012-01-01

    A simple and direct method has been developed for synthesis of nitriles based on one-pot reaction of aromatic aldehydes with three different kind of reagents:CeCl3·7H2O/KI/H2O2,CeCl3·7H2O/KI/UHP and (NH4)2Ce(NO3)6/KI/H2O2 in aqueous ammonia.

  16. Characterization of the rat Class 3 aldehyde dehydrogenase gene promoter.

    OpenAIRE

    Xie, Y Q; Takimoto, K; Pitot, H. C.; Miskimins, W K; Lindahl, R

    1996-01-01

    The Class 3 aldehyde dehydrogenase gene (ALDH-3) is differentially expressed. Expression is either constitutive or xenobiotic inducible via an aromatic hydrocarbon (Ah) receptor-mediated pathway, depending upon the tissue. A series of studies were performed to examine the regulation of rat ALDH-3 basal expression. DNase I footprint analysis identified four DNA regions within the proximal 1 kb of the 5' flanking region of rat ALDH-3 which interact with regulatory proteins. Reporter gene and ge...

  17. γ-Unsaturated aldehydes as potential Lilial replacers.

    Science.gov (United States)

    Schroeder, Martin; Mathys, Marion; Ehrensperger, Nadja; Büchel, Michelle

    2014-10-01

    A series of Claisen rearrangements was undertaken in order to find a replacement for Lilial (=3-(4-(tert-butyl)phenyl)-2-methylpropanal), a high-tonnage perfumery ingredient with a lily-of-the-valley odour, which is a CMR2 material [1]. 5,7,7-Trimethyl-4-methyleneoctanal (10), the synthesis of which is described, became the main lead. It possesses an odour which is very close to that of Lilial but lacks its substantivity. Aldehydes with higher molecular weights than that of 10 were, therefore, synthesised in order to boost substantivity and to understand the structural requirements for a 'Lilial' odour. The aldehydes were obtained via Claisen rearrangements of 'exo-methylidene' vinyl ethers, allenyl vinyl ethers, or allenyl allyl ethers. Alternatively, coupling of terminal alkynes with allyl alcohols led to the desired aldehydes. Derivatives of 10 and their sila analogues were also synthesised. The olfactory properties of all synthesised molecules were evaluated for possible structure-odour relationships (SOR). PMID:25329790

  18. Modeling and Simulations in Photoelectrochemical Water Oxidation: From Single Level to Multiscale Modeling

    NARCIS (Netherlands)

    Zhang, X.; Bieberle, A.

    2016-01-01

    This review summarizes recent developments, challenges, and strategies in the field of modeling and simulations of photoelectrochemical (PEC) water oxidation. We focus on water splitting by metal-oxide semiconductors and discuss topics such as theoretical calculations of light absorption, band gap/b

  19. Can iron oxides remove Cr(VI) from drinking water at sub-ppb levels?

    Science.gov (United States)

    Kaprara, Efthymia; Simeonidis, Konstantinos; Samaras, Petros; Zouboulis, Anastasios; Mitrakas, Manassis

    2013-04-01

    Hexavalent chromium [Cr(VI)] has long been recognized as a potential carcinogen via inhalation, in contrast to trivalent chromium [Cr(III)] which is 100 times less toxic and also a necessary nutrient, essential to human glucidic metabolism. Nowadays there is an increasing concern that Cr(VI) is also carcinogenic by the oral route of exposure, while an increased number of publications indicate that Cr(VI) is a common natural pollutant. Hexavalent chromium formation is attributed to natural oxidation of Cr(III) in ultramafic derived soils and ophiolithic rocks. To verify this theory, drinking water samples were collected from targeted areas of Greece e.g. areas in which the geological background is predominated by ultramafic minerals and the water supply depends mainly on groundwater resources. Valuable guide for the samples collection was the geological map of Greece and emphasis was given to regions where the natural occurrence of Cr(VI) is thought to be more possible. A wide range of Cr concentrations (2-100 μg/L) were detected in the areas studied, with most of them ranging below the current limit of 50 μg/L, and the Cr(VI) concentration being more than 90% of the total. Since the Cr(VI) affects significant part of population worldwide, a debate was established concerning the enforcement of stringent regulation, which also demands the drinking water treatment processes re-evaluation in view of Cr(VI) removal at sub-ppb level. In this regard, adsorption has evolved as the front line of defense for chromium removal. The motivation of this work was to investigate the efficiency of iron oxides for the adsorption of Cr(VI) from drinking water and its removal at sub-ppb levels. The adsorbents examined included iron oxy-hydroxides and magnetite prepared using common low cost iron salts. Their effectiveness as Cr(VI) adsorbents was evaluated through the decrease of a Cr(VI) concentration of 100μg/L prepared in NSF water at pH 7. Preliminary batch experiments did not

  20. Asymmetric synthesis of biaryl atropisomers by dynamic resolution on condensation of biaryl aldehydes with (−-ephedrine or a proline-derived diamine

    Directory of Open Access Journals (Sweden)

    2008-12-01

    Full Text Available Atropisomeric biaryl aldehydes undergo diastereoselective condensation with (−-ephedrine and with a proline-derived diamine, with selectivity highly dependent on solvent, temperature and reaction conditions. Levels of thermodynamic control up to 5:1 may be obtained by heating the diamine with the aldehyde in a sealed tube. Alternatively, crystallisation-induced dynamic transformation allows isolation of a single diastereoisomer in up to 85% yield. Hydrolysis and reduction of the major diastereoisomeric product of the reaction yields atropisomeric biaryls in >99:1 enantiomeric ratios.

  1. Evaluation of alcohol dehydrogenase and aldehyde dehydrogenase enzymes as bi-enzymatic anodes in a membraneless ethanol microfluidic fuel cell

    Science.gov (United States)

    Galindo-de-la-Rosa, J.; Arjona, N.; Arriaga, L. G.; Ledesma-García, J.; Guerra-Balcázar, M.

    2015-12-01

    Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (AldH) enzymes were immobilized by covalent binding and used as the anode in a bi-enzymatic membraneless ethanol hybrid microfluidic fuel cell. The purpose of using both enzymes was to optimize the ethanol electro-oxidation reaction (EOR) by using ADH toward its direct oxidation and AldH for the oxidation of aldehydes as by-products of the EOR. For this reason, three enzymatic bioanode configurations were evaluated according with the location of enzymes: combined, vertical and horizontally separated. In the combined configuration, a current density of 16.3 mA cm-2, a voltage of 1.14 V and a power density of 7.02 mW cm-2 were obtained. When enzymes were separately placed in a horizontal and vertical position the ocp drops to 0.94 V and to 0.68 V, respectively. The current density also falls to values of 13.63 and 5.05 mA cm-2. The decrease of cell performance of bioanodes with separated enzymes compared with the combined bioanode was of 31.7% and 86.87% for the horizontal and the vertical array.

  2. Persistent high levels of plasma oxidized low-density lipoprotein after acute myocardial infarction predict stent restenosis

    NARCIS (Netherlands)

    T. Naruko; M. Ueda; S. Ehara; A. Itoh; K. Haze; N. Shirai; Y. Ikura; M. Ohsawa; H. Itabe; Y. Kobayashi; H. Yamagishi; M. Yoshiyama; J. Yoshikawa; A.E. Becker

    2006-01-01

    Objective-Recently, elevated levels of plasma oxidized low-density lipoprotein (LDL) have been shown to relate to plaque instability in human atherosclerotic lesions. We investigated prospectively patients admitted with acute myocardial infarction (AMI) who underwent primary coronary stenting to eva

  3. Impaired oxidative capacity due to decreased CPT1b levels as a contributing factor to fat accumulation in obesity

    DEFF Research Database (Denmark)

    Ratner, Cecilia; Madsen, Andreas Nygaard; Kristensen, Line Vildbrad;

    2015-01-01

    to ghrelin's orexigenic effects as well as ghrelin-induced attenuation of activity and energy expenditure. Thus, increased fat accumulation characterizing obesity may be caused by impaired oxidative capacity due to decreased carnitine palmitoyltransferase 1b levels in the white adipose tissue, while ghrelin...

  4. Effect of oxygen level on the oxidative stability of two different retail pork products stored using modified atmosphere packaging (MAP)

    DEFF Research Database (Denmark)

    Spanos, Dimitrios; Ann Tørngren, Mari; Christensen, Mette;

    2016-01-01

    The characteristics and the oxidative stability of pork steaks and of pork mince were investigated during 2, 5 and 7 days of refrigerated storage using oxygen (O2) levels of 0%, 20%, 50% and 80% in modified atmosphere packaging (MAP). Steaks stored during 7 days were not affected by an increase...

  5. Oxidative DNA damage levels and catalase activity in the clam Ruditapes decussatus as pollution biomarkers of Tunisian marine environment.

    Science.gov (United States)

    Jebali, Jamel; Banni, Mohamed; de Almeida, Eduardo Alves; Boussetta, Hamadi

    2007-01-01

    Levels of the oxidative DNA damage 7, 8-dihydro-8-oxo-2'-deoxyguanosine (8-oxodG) and catalase (CAT) activity were measured in the digestive gland and gills of clams Ruditapes decussatus, related to the presence of pollutants along Tunisian marine environment. Increased levels of CAT were observed in tissues of clams from all the sites studied, compared to control values, and elevated 8-oxodG levels were observed at specific sites. Results obtained in this work indicate that the measurement of 8-oxodG levels and CAT activity in tissues of R. decussatus is promising in pollution monitoring studies of the Tunisian marine environment. PMID:16897518

  6. GRE2 from Scheffersomyces stipitis as an aldehyde reductase contributes tolerance to aldehyde inhibitors derived from lignocellulosic biomass.

    Science.gov (United States)

    Wang, Xu; Ma, Menggen; Liu, Z Lewis; Xiang, Quanju; Li, Xi; Liu, Na; Zhang, Xiaoping

    2016-08-01

    Scheffersomyces (Pichia) stipitis is one of the most promising yeasts for industrial bioethanol production from lignocellulosic biomass. S. stipitis is able to in situ detoxify aldehyde inhibitors (such as furfural and 5-hydroxymethylfurfural (HMF)) to less toxic corresponding alcohols. However, the reduction enzymes involved in this reaction remain largely unknown. In this study, we reported that an uncharacterized open reading frame PICST_72153 (putative GRE2) from S. stipitis was highly induced in response to furfural and HMF stresses. Overexpression of this gene in Saccharomyces cerevisiae improved yeast tolerance to furfural and HMF. GRE2 was identified as an aldehyde reductase which can reduce furfural to FM with either NADH or NADPH as the co-factor and reduce HMF to FDM with NADPH as the co-factor. This enzyme can also reduce multiple aldehydes to their corresponding alcohols. Amino acid sequence analysis indicated that it is a member of the subclass "intermediate" of the short-chain dehydrogenase/reductase (SDR) superfamily. Although GRE2 from S. stipitis is similar to GRE2 from S. cerevisiae in a three-dimensional structure, some differences were predicted. GRE2 from S. stipitis forms loops at D133-E137 and T143-N145 locations with two α-helices at E154-K157 and E252-A254 locations, different GRE2 from S. cerevisiae with an α-helix at D133-E137 and a β-sheet at T143-N145 locations, and two loops at E154-K157 and E252-A254 locations. This research provided guidelines for the study of other SDR enzymes from S. stipitis and other yeasts on tolerant mechanisms to aldehyde inhibitors derived from lignocellulosic biomass. PMID:27003269

  7. Determination of oxidative stress in vitiligo by measuring superoxide dismutase and catalase levels in vitiliginous and non-vitiliginous skin

    Directory of Open Access Journals (Sweden)

    Sravani P

    2009-01-01

    Full Text Available Background: Vitiligo is an acquired disorder characterized by circumscribed depigmented macules devoid of identifiable melanocytes. Complex genetic, immunological, neural and self destructive mechanisms interplay in its pathogenesis. According to autocytotoxic hypothesis, oxidative stress has been suggested to be the initial pathogenic event in melanocyte degeneration. Aims: The aim of our investigation was to evaluate the role of oxidative stress by measuring levels of the antioxidant enzymes superoxide dismutase (SOD and catalase (CAT in lesional and normal skin of patients with vitiligo and in the skin of normal controls. Methods: We determined the activity of SOD in lesional and non-lesional skin and CAT in lesional skin only of 25 vitiligo patients and 25 controls by using the spectrophotometric assay and Aebi′s method, respectively. Results: There was statistically significant increase in the levels of SOD in vitiliginous and non vitiliginous skin of patient group compared to the control group ( P < 0.001. No significant difference was found between the levels of SOD in lesional skin and non-lesional skin of vitiligo patients. The levels of CAT in the skin of patients were found to be significantly lower than those of controls ( P < 0.001. Conclusions: There is increased oxidative stress in vitiligo as is indicated by high levels of SOD and low levels of CAT in the skin of vitiligo patients.

  8. Cardiovascular diseases: oxidative damage and antioxidant protection.

    Science.gov (United States)

    Zhang, P-Y; Xu, X; Li, X-C

    2014-10-01

    Atherosclerosis, the hardening of arteries under oxidative stress is related to oxidative changes of low density lipoproteins (LDL). The antioxidants prevent the formation of oxidized LDL during atherogenesis. Perhaps more than one mechanism is involved in the atherosclerosis disease where LDL is oxidized in all the cells of arterial wall during the development of this disease. The oxidation of LDL produces lipid peroxidation products such as isoprostans from arachidonic, eicosapentaenoic and docosahexaenoic acids, oxysterols from cholesterol, hydroxyl fatty acids, lipid peroxides and aldehydes. The lipid peroxidation bioassay can serve as a marker for the risk of cardiovascular. An in vivo test of levels of oxidative lipid damage is an early prediction of development of cardiovascular disease (CVD). Serum paraoxonase (PON) activity is correlated to severity of the coronary artery disease. The antioxidants level in the serum and serum paraoxonase activity provides information for the risk of CVD. The antioxidant enzyme superoxide dismutase is responsible for dismutation of superoxide, a free radical chain initiator. The subcellular changes in the equilibrium in favor of free radicals can cause increase in the oxidative stress which leads to cardiomyopathy, heart attack or cardiac dysfunction. The oxidative damage and defense of heart disease has been reported where dietary antioxidants protect the free radical damage to DNA, proteins and lipids. The ascorbic acid, vitamin C is an effective antioxidant and high vitamin E intake can reduce the risk of coronary heart disease (CHD) by inhibition of atherogenic forms of oxidized LDL. The vitamin A and beta-carotene protect lipid peroxidation and provitamin-A activity. It has been recently suggested that the protection of oxidative damage and related CVD is best served by antioxidants found in the fruits and vegetables. The oxidative damage and antioxidant protection of CVD have been described here. PMID:25392110

  9. Signal transduction pathways in erythrocyte nitric oxide metabolism under high fibrinogen levels

    Science.gov (United States)

    Saldanha, Carlota; Freitas, T.; Lopez de Almeida, J. P.; Silva-Herdade, A.

    2014-05-01

    Previous studies show that the fibrinogen molecule modulates the metabolism of nitric oxide (NO) in erythrocyte. The in vitro induced hiperfibrinogenemia interferes in the metabolism of the NO in the erythrocyte in dependence of the phosphorylation degree of the band 3. The soluble form of fibrinogen binds into CD47 protein present in the erythrocyte membrane. The soluble thrombomodulin is an inflammatory marker that binds to the erythrocyte CD47 in a site with a sequence peptide known as 4N1K. A study done in vitro shows that when hiperfibrinogenemia was induced in the presence of the peptide 4N1K agonist of CD47 it were observed variations in the efflux of NO from erythrocyte and an increase in the concentrations of GSNO, peroxinitrite, nitrite and nitrate of the erythrocytes. The aim of this work was to study the influence of the peptide 4N1K, on the metabolism of NO in the erythrocyte under high fibrinogen concentration and in the presence of inhibitors of the status of phosphorylation of protein band 3. In this in vitro study, whole blood samples were harvested from healthy subjects and NO, peroxynitrite, nitrite, nitrate and S-nitro-glutathione (GSNO) were determined in presence of 4N1K, calpeptine, Syk inhibitor and under high fibrinogen concentrations. The results obtained in erythrocytes under high fibrinogen levels when 4N1K is present with the Syk inhibitor or with calpeptine, showed in relation to the control samples increased significant concentrations of efflux of NO and of peroxynitrite, nitrite, nitrate and GSNO. In conclusion it was verified that in the in vitro model of hiperfibrinogenemia the peptide 4N1K, agonist of CD47, induces mobilization of NO in the erythrocyte in dependence of the status of phosphorylation of protein band 3.

  10. Transformations and Tautomeric Equilibrium among Different Intermediates in Proline-Catalyzed Reactions of Aldehydes or Ketones

    Institute of Scientific and Technical Information of China (English)

    Li-hua Gan; Qing Chang; Jin Zhou

    2013-01-01

    The enamines,iminium ions,and oxazolidinones are thought to be the key intermediates in the proline-catalyzed reactions of aldehydes or ketones,but there is an extensive controversy about their roles.Here,the corresponding transition states connecting any two of the three kinds of species are located at the ωB97XD/6-311++G** level of theory.The calculations demonstrate that the oxazolidinones are the predominant species in both the gas phase and solvents; there exists tautomeric equilibrium among these species and the equilibriums are controlled by the employed solvents and temperature in the reaction.These results demonstrate that the concentration and role of the mentioned species are controlled by the employed solvent and temperature.A new reaction pathway is presented herein for the transformation between iminium ions and oxazolidinones through iminium ion-water complex and oxazolidinone-water complex.The calculations demonstrate that the rate-limiting step in proline-catalyzed Mannich reaction between acetaldehyde/keteones and N-Boc imines is the formation of the C-C bond rather than the intermediates tautomerization.These calculations rationalize the available experimental observations and can be valuable in optimizing the experimental conditions of asymmetric organic-catalyzed reactions of aldehydes or ketones.

  11. Defensome against toxic diatom aldehydes in the sea urchin Paracentrotus lividus.

    Directory of Open Access Journals (Sweden)

    Vincenzo Marrone

    Full Text Available Many diatom species produce polyunsaturated aldehydes, such as decadienal, which compromise embryonic and larval development in benthic organisms. Here newly fertilized Paracentrotus lividus sea urchins were exposed to low concentration of decadienal and the expression levels of sixteen genes, implicated in a broad range of functional responses, were followed by Real Time qPCR in order to identify potential decadienal targets. We show that at low decadienal concentrations the sea urchin Paracentrotus lividus places in motion different classes of genes to defend itself against this toxic aldehyde, activating hsp60 and two proteases, hat and BP10, at the blastula stage and hsp56 and several other genes (14-3-3ε, p38 MAPK, MTase, and GS at the prism stage. At this latter stage all genes involved in skeletogenesis (Nec, uni, SM50 and SM30 were also down-expressed, following developmental abnormalities that mainly affected skeleton morphogenesis. Moreover, sea urchin embryos treated with increasing concentrations of decadienal revealed a dose-dependent response of activated target genes. Finally, we suggest that this orchestrated defense system against decadienal represents part of the chemical defensome of P. lividus affording protection from environmental toxicants.

  12. Chirped Pulse-Fourier Transform Microwave Spectroscopy of Ethyl 3-METHYL-3-PHENYLGLYCIDATE (strawberry Aldehyde)

    Science.gov (United States)

    Shipman, Steven T.; Neill, Justin L.; Muckle, Matt T.; Suenram, Richard D.; Pate, Brooks H.

    2009-06-01

    Strawberry aldehyde (C_{12} O_3 H_{14}), a common artificial flavoring compound, has two non-interconvertible conformational families defined by the relative stereochemistry around its epoxide carbons. In one family, referred to as the trans because the two large substituents (a phenyl ring and an ethyl ester) are on opposite sides of the epoxide ring, these two substituents are unable to interact with each other. However, in the cis family, there is a long-range interaction that is difficult to accurately capture in electronic structure calculations. Three trans and two cis conformations have been assigned by broadband chirped pulse Fourier transform microwave spectroscopy, along with the C-13 isotopomers in natural abundance for one conformer from each of the families. The agreement of the rotational constants, relative dipole moments, and relative energies between theory and experiment is excellent, even at relatively crude levels of theory, for the trans family, but is quite poor for the cis conformers. In addition, due to the reactivity of strawberry aldehyde and the high temperature to which it must be heated to yield a suitable vapor pressure, several decomposition products have been assigned, and more, as of yet unassigned, are likely to be present. This project demonstrates some of the challenges in performing large-molecule rotational spectroscopy.

  13. High-level neutron-coincidence-counter (HLNCC) implementation: assay of the plutonium content of mixed-oxide fuel assemblies

    International Nuclear Information System (INIS)

    The portable High-Level Neutron Coincidence Counter is used to assay the 240Pu-effective loading of a reference mixed-oxide fuel assembly by neutron coincidence counting. We have investigated the effects on the coincidence count rate of the total fuel loading (UO2 + PuO2), the fissile loading, the fuel rod diameter, and the fuel rod pattern. The coincidence count rate per gram of 240Pu-effective per centimeter is primarily dependent on the total fuel loading of the assembly; the higher the loading, the higher the coincidence count rate. Detailed procedures for the assay of mixed-oxide fuel assemblies are developed

  14. Neuroglobin in Breast Cancer Cells: Effect of Hypoxia and Oxidative Stress on Protein Level, Localization, and Anti-Apoptotic Function.

    Directory of Open Access Journals (Sweden)

    Marco Fiocchetti

    Full Text Available The over-expression of human neuroglobin (NGB, a heme-protein preferentially expressed in the brain, displays anti-apoptotic effects against hypoxic/ischemic and oxidative stresses enhancing neuron survival. As hypoxic and oxidative stress injury frequently occurs in fast proliferating neoplastic tissues, here, the effect of these stressors on the level, localization, and anti-apoptotic function of NGB in wild type and NGB-stable-silenced MCF-7 breast cancer cells has been assessed. The well-known endogenous NGB inducer 17β-estradiol (E2 has been used as positive control. The median pO2 present in tumor microenvironment of breast cancer patients (i.e., 2% O2 does not affect the NGB level in breast cancer cells, whereas hydrogen peroxide and lead(IV acetate, which increase intracellular reactive oxygen species (ROS level, enhance the NGB levels outside the mitochondria and still activate apoptosis. However, E2-induced NGB up-regulation in mitochondria completely reverse lead(IV acetate-induced PARP cleavage. These results indicate that the NGB level could represent a marker of oxidative-stress in MCF-7 breast cancer cells; however, the NGB ability to respond to injuring stimuli by preventing apoptosis requires its re-allocation into the mitochondria. As a whole, present data might lead to a new direction in understanding NGB function in cancer opening new avenues for the therapeutic intervention.

  15. Neuroglobin in Breast Cancer Cells: Effect of Hypoxia and Oxidative Stress on Protein Level, Localization, and Anti-Apoptotic Function

    Science.gov (United States)

    Fiocchetti, Marco; Cipolletti, Manuela; Leone, Stefano; Naldini, Antonella; Carraro, Fabio; Giordano, Daniela; Verde, Cinzia; Ascenzi, Paolo; Marino, Maria

    2016-01-01

    The over-expression of human neuroglobin (NGB), a heme-protein preferentially expressed in the brain, displays anti-apoptotic effects against hypoxic/ischemic and oxidative stresses enhancing neuron survival. As hypoxic and oxidative stress injury frequently occurs in fast proliferating neoplastic tissues, here, the effect of these stressors on the level, localization, and anti-apoptotic function of NGB in wild type and NGB-stable-silenced MCF-7 breast cancer cells has been assessed. The well-known endogenous NGB inducer 17β-estradiol (E2) has been used as positive control. The median pO2 present in tumor microenvironment of breast cancer patients (i.e., 2% O2) does not affect the NGB level in breast cancer cells, whereas hydrogen peroxide and lead(IV) acetate, which increase intracellular reactive oxygen species (ROS) level, enhance the NGB levels outside the mitochondria and still activate apoptosis. However, E2-induced NGB up-regulation in mitochondria completely reverse lead(IV) acetate-induced PARP cleavage. These results indicate that the NGB level could represent a marker of oxidative-stress in MCF-7 breast cancer cells; however, the NGB ability to respond to injuring stimuli by preventing apoptosis requires its re-allocation into the mitochondria. As a whole, present data might lead to a new direction in understanding NGB function in cancer opening new avenues for the therapeutic intervention. PMID:27149623

  16. Selective oxidation of benzylic alcohols using copper-manganese mixed oxide nanoparticles as catalyst

    Directory of Open Access Journals (Sweden)

    Roushown Ali

    2015-07-01

    Full Text Available The catalytic activity of copper-manganese (CuMn2 mixed oxide nanoparticles (Cu/Mn = 1:2 has been studied for the selective oxidation of benzylic alcohols to the corresponding aldehydes using molecular oxygen as an oxidizing agent. The CuMn2 mixed oxide showed excellent catalytic activity for the oxidation of benzylic alcohols to the corresponding aldehydes with high selectivity (>99%. The complete conversion (100% of all the benzylic alcohols to the corresponding aldehydes is achieved within a short reaction period at 102 °C. The catalytic performance is obtained to be dependent on the electronic and steric effects of the substituents present on the phenyl ring. Electron withdrawing and bulky groups attached to the phenyl ring required longer reaction time for a complete conversion of the benzylic alcohols.

  17. DLTS study of annihilation of oxidation induced deep-level defects in Ni/SiO2/-Si MOS structures

    Indian Academy of Sciences (India)

    N Shashank; Sanjeev K Gupta; K V Madhu; J Akhtar; R Damle

    2011-12-01

    This paper describes the fabrication of MOS capacitor and DLTS study of annihilation of deeplevel defects upon thermal annealing. Ni/SiO2/-Si MOS structures fabricated on -type Si wafers were investigated for process-induced deep-level defects. The deep-level traps in Si substrates induced during the processing of Ni/SiO2/-Si have been investigated using deep-level transient spectroscopy (DLTS). A characteristic deep-level defect at C = 0.49 eV which was introduced during high-temperature thermal oxidation process was detected. The trap position was found to shift to different energy levels (C = 0.43, 0.46 and 0.34 eV) during thermal annealing process. The deep-level trap completely anneals at 350°C. Significant reduction in trap density with an increase in recombination life time and substrate doping concentration as a function of isochronal annealing were observed.

  18. Optimization of the Expression of Human Aldehyde Oxidase for Investigations of Single-Nucleotide Polymorphisms.

    Science.gov (United States)

    Foti, Alessandro; Hartmann, Tobias; Coelho, Catarina; Santos-Silva, Teresa; Romão, Maria João; Leimkühler, Silke

    2016-08-01

    Aldehyde oxidase (AOX1) is an enzyme with broad substrate specificity, catalyzing the oxidation of a wide range of endogenous and exogenous aldehydes as well as N-heterocyclic aromatic compounds. In humans, the enzyme's role in phase I drug metabolism has been established and its importance is now emerging. However, the true physiologic function of AOX1 in mammals is still unknown. Further, numerous single-nucleotide polymorphisms (SNPs) have been identified in human AOX1. SNPs are a major source of interindividual variability in the human population, and SNP-based amino acid exchanges in AOX1 reportedly modulate the catalytic function of the enzyme in either a positive or negative fashion. For the reliable analysis of the effect of amino acid exchanges in human proteins, the existence of reproducible expression systems for the production of active protein in ample amounts for kinetic, spectroscopic, and crystallographic studies is required. In our study we report an optimized expression system for hAOX1 in Escherichia coli using a codon-optimized construct. The codon-optimization resulted in an up to 15-fold increase of protein production and a simplified purification procedure. The optimized expression system was used to study three SNPs that result in amino acid changes C44W, G1269R, and S1271L. In addition, the crystal structure of the S1271L SNP was solved. We demonstrate that the recombinant enzyme can be used for future studies to exploit the role of AOX in drug metabolism, and for the identification and synthesis of new drugs targeting AOX when combined with crystallographic and modeling studies. PMID:26842593

  19. Inhibition of human alcohol and aldehyde dehydrogenases by acetaminophen: Assessment of the effects on first-pass metabolism of ethanol.

    Science.gov (United States)

    Lee, Yung-Pin; Liao, Jian-Tong; Cheng, Ya-Wen; Wu, Ting-Lun; Lee, Shou-Lun; Liu, Jong-Kang; Yin, Shih-Jiun

    2013-11-01

    Acetaminophen is one of the most widely used over-the-counter analgesic, antipyretic medications. Use of acetaminophen and alcohol are commonly associated. Previous studies showed that acetaminophen might affect bioavailability of ethanol by inhibiting gastric alcohol dehydrogenase (ADH). However, potential inhibitions by acetaminophen of first-pass metabolism (FPM) of ethanol, catalyzed by the human ADH family and by relevant aldehyde dehydrogenase (ALDH) isozymes, remain undefined. ADH and ALDH both exhibit racially distinct allozymes and tissue-specific distribution of isozymes, and are principal enzymes responsible for ethanol metabolism in humans. In this study, we investigated acetaminophen inhibition of ethanol oxidation with recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and inhibition of acetaldehyde oxidation with recombinant human ALDH1A1 and ALDH2. The investigations were done at near physiological pH 7.5 and with a cytoplasmic coenzyme concentration of 0.5 mM NAD(+). Acetaminophen acted as a noncompetitive inhibitor for ADH enzymes, with the slope inhibition constants (Kis) ranging from 0.90 mM (ADH2) to 20 mM (ADH1A), and the intercept inhibition constants (Kii) ranging from 1.4 mM (ADH1C allozymes) to 19 mM (ADH1A). Acetaminophen exhibited noncompetitive inhibition for ALDH2 (Kis = 3.0 mM and Kii = 2.2 mM), but competitive inhibition for ALDH1A1 (Kis = 0.96 mM). The metabolic interactions between acetaminophen and ethanol/acetaldehyde were assessed by computer simulation using inhibition equations and the determined kinetic constants. At therapeutic to subtoxic plasma levels of acetaminophen (i.e., 0.2-0.5 mM) and physiologically relevant concentrations of ethanol (10 mM) and acetaldehyde (10 μm) in target tissues, acetaminophen could inhibit ADH1C allozymes (12-26%) and ADH2 (14-28%) in the liver and small intestine, ADH4 (15-31%) in the stomach, and ALDH1A1 (16-33%) and ALDH2 (8.3-19%) in all 3 tissues. The

  20. Variation of interface trap level charge density within the bandgap of 4H-SiC with varying oxide thickness

    Indian Academy of Sciences (India)

    Sanjeev K Gupta; A Azam; J Akhtar

    2011-01-01

    Interfacial characteristics of metal oxide-silicon carbide (MOSiC) structure with different thickness of SiO2, thermally grown in steam ambient on Si-face of 4H-SiC (0 0 0 1) substrate were investigated. Variations in interface trapped level density (Dit) was systematically studied employing high-low (H-L) frequency – method. It was found that the distribution of Dit within the bandgap of 4H-SiC varied with oxide thickness. The calculated Dit value near the midgap of 4H-SiC remained almost stable for all oxide thicknesses in the range of 109 –1010 cm-2 eV-1. The Dit near the conduction band edge had been found to be of the order of 1011 cm-2 eV-1 for thicker oxides and for thinner oxides Dit was found to be the range of 1010 cm-2 eV-1. The process had direct relevance in the fabrication of MOS-based device structures.

  1. High levels of γ-H2AX foci and cell membrane oxidation in adolescents with type 1 diabetes

    International Nuclear Information System (INIS)

    Highlights: • We aimed to detect signs of very early damage in peripheral cells of T1DM adolescents. • T1DM patients had high levels of oxidized cells and reduced expression of iNOS and NO. • Highly mutagenic lesions were markedly increased in the diabetic group, mainly in females. • The observed damage might increase the risk of cancer in the patients later in life. - Abstract: Oxidative stress caused by an excess of free radicals is implicated in the pathogenesis and development of type 1 diabetes mellitus (T1DM) and, in turn, it can lead to genome damage, especially in the form of DNA double-strand break (DSB). The DNA DSB is a potentially carcinogenic lesion for human cells. Thus, we aimed to evaluate whether the level of oxidative stress was increased in peripheral blood lymphocytes of a group of affected adolescents. In 35 T1DM adolescents and 19 healthy controls we assessed: (1) spontaneous and H2O2-induced oxidation of cell membrane using a fluorescence lipid probe; (2) spontaneous and LPS-induced expression of iNOS protein and indirect NO determination via cytofluorimetric analysis of O2−; (3) immunofluorescent detection of the basal level of histone H2AX phosphorylation (γ-H2AX foci), a well-validated marker of DNA DSB. In T1DM, the frequencies of oxidized cells, both spontaneous and H2O2-induced (47.13 ± 0.02) were significantly higher than in controls (35.90 ± 0.03). Patients showed, in general, both a reduced iNOS expression and production of NO. Furthermore, the level of spontaneous nuclear damage, quantified as γ-H2AX foci, was markedly increased in T1DM adolescents (6.15 ± 1.08% of γ-H2AX+ cells; 8.72 ± 2.14 γ-H2AXF/n; 9.26 ± 2.37 γ-H2AXF/np), especially in females. In the present study, we confirmed the role that oxidative stress plays in the disease damaging lipids of cell membrane and, most importantly, causing genomic damage in circulating white blood cells of affected adolescents. This also indicates that oxidative stress

  2. Gold-catalyzed oxidation of arylallenes: Synthesis of quinoxalines and benzimidazoles

    OpenAIRE

    Ying Chen; Dan-Wen Zhuang; Dong-Mei Cui; Chen Zhang

    2011-01-01

    A gold-catalyzed oxidation of arylallenes to form α-diketones and aldehydes in good yields is presented. Further directed synthesis of quinoxalines and benzimidazoles, via the condensation of the resulting α-diketones and aldehydes with benzene-1,2-diamine, was achieved in high yields.

  3. Decreased Glutathione Peroxidase Activities with Concomitant Increased Oxidized Glutathione Levels among Residents in an Arsenic Contaminated Community of Southern Thailand

    Directory of Open Access Journals (Sweden)

    Warangkana CHUNGLOK

    2008-01-01

    Full Text Available Glutathione peroxidase (GPx and glutathione are important antioxidants responsible for the scavenging of reactive oxygen species (ROS. It has been shown that changes in GPx activities and glutathione levels are associated with various diseases including toxic chemical related diseases and cancers. The study aimed to determine the levels of GPx activity and glutathione among residents in Ron Phibun district, an arsenic-exposed area. Blood samples were obtained from 32 volunteers in the Thasala group, a nearby nonarsenic-exposed area and 36 residents in the Ron Phibun group. Red cell lysates were subjected to analysis of GPx activity and glutathione. The results showed that GPx activities were significantly decreased among study subjects from Ron Phibun (p < 0.05. Interestingly, oxidized glutathione (GSSG levels were significantly increased compared with those from Thasala (p < 0.05. Total glutathione and reduced glutathione (GSH levels were not different among the two groups. Mean values of GPx activities, total glutathione and GSH tended to decrease among high-exposure subjects compared to low-exposure subjects. This was concomitant with a slight increase in GSSG levels among high-exposure subjects. The levels of GPx activities and GSSG may be early biomarkers for low levels of oxidative stress in a mining area affected with arsenic poisoning.

  4. Monolayer structures of alkyl aldehydes: Odd-membered homologues

    OpenAIRE

    Phillips, T. K.; Clarke, Stuart M.; Castro Arroyo, Miguel Ángel; Millán, Carmen; Medina, Santiago

    2011-01-01

    Crystalline monolayers of three aldehydes with an odd number of carbon atoms in the alkyl chain (C 7, C 9 and C 11) at low coverages are observed by a combination of X-ray and neutron diffraction. Analysis of the diffraction data is discussed and possible monolayer crystal structures are proposed; although unique structures could not be ascertained for all molecules. We conclude that the structures are flat on the surface, with the molecules lying in the plane of the layer. The C 11 homologue...

  5. Monolayer structures of alkyl aldehydes: Odd-membered homologues

    International Nuclear Information System (INIS)

    Crystalline monolayers of three aldehydes with an odd number of carbon atoms in the alkyl chain (C7, C9 and C11) at low coverages are observed by a combination of X-ray and neutron diffraction. Analysis of the diffraction data is discussed and possible monolayer crystal structures are proposed; although unique structures could not be ascertained for all molecules. We conclude that the structures are flat on the surface, with the molecules lying in the plane of the layer. The C11 homologue is determined to have a plane group of either p2, pgb or pgg, and for the C7 homologue the p2 plane group is preferred.

  6. Hydrogenations without Hydrogen: Titania Photocatalyzed Reductions of Maleimides and Aldehydes

    Directory of Open Access Journals (Sweden)

    David W. Manley

    2014-09-01

    Full Text Available A mild procedure for the reduction of electron-deficient alkenes and carbonyl compounds is described. UVA irradiations of substituted maleimides with dispersions of titania (Aeroxide P25 in methanol/acetonitrile (1:9 solvent under dry anoxic conditions led to hydrogenation and production of the corresponding succinimides. Aromatic and heteroaromatic aldehydes were reduced to primary alcohols in similar titania photocatalyzed reactions. A mechanism is proposed which involves two proton-coupled electron transfers to the substrates at the titania surface.

  7. Nuclear alkylated pyridine aldehyde polymers and conductive compositions thereof

    Science.gov (United States)

    Rembaum, A.; Singer, S. (Inventor)

    1970-01-01

    A thermally stable, relatively conductive polymer was disclosed. The polymer was synthesized by condensing in the presence of catalyst a 2, 4, or 6 nuclear alklylated 2, 3, or 4 pyridine aldehyde or quaternary derivatives thereof to form a polymer. The pyridine groups were liked by olefinic groups between 2-4, 2-6, 2-3, 3-4, 3-6 or 4-6 positions. Conductive compositions were prepared by dissolving the quaternary polymer and an organic charge transfer complexing agent such as TCNQ in a mutual solvent such as methanol.

  8. Microwave Assisted Solvent Free Synthesis of Azomethines from Aryl Aldehydes on Melamin Formaldehyde as Solid Support

    OpenAIRE

    Ramin Rezaei; Mohammadi, Mohammad K; Tahereh Ranjbar

    2011-01-01

    Various aryl aldehydes underwent prompt one pot conversion into the corresponding azomethines in high yields by reacting with hydroxylamine hydrochloride supported on melamine formaldehyde under microwave irradiation.

  9. The Impact of Rendered Protein Meal Oxidation Level on Shelf-Life, Sensory Characteristics, and Acceptability in Extruded Pet Food

    Science.gov (United States)

    Chanadang, Sirichat; Koppel, Kadri; Aldrich, Greg

    2016-01-01

    Simple Summary Sensory analysis was used to determine the changes due to the storage time on extruded pet food prepared from two different rendered protein meals: (i) beef meat and bone meal (BMBM); (ii) chicken byproduct meal (CPBM). Extrusion is a process where feed is pressed through a die in order to create shapes and increase digestibility. Descriptive sensory analysis using a human panel found an increase in undesirable sensory attributes (e.g., oxidized oil, rancid) in extruded pet food over storage time, especially the one prepared from chicken by product meal without antioxidants. The small increase in oxidized and rancid aromas of BMBM samples did not affect pet owners’ acceptability of the products. CPBM samples without antioxidants showed a notable increase in oxidized and rancid aroma over storage time and, thus, affected product acceptability negatively. This finding indicated that human sensory analysis can be used as a tool to track the changes of pet food characteristics due to storage, as well as estimate the shelf-life of the products. Abstract Pet foods are expected to have a shelf-life for 12 months or more. Sensory analysis can be used to determine changes in products and to estimate products’ shelf-life. The objectives of this study were to (1) investigate how increasing levels of oxidation in rendered protein meals used to produce extruded pet food affected the sensory properties and (2) determine the effect of shelf-life on pet owners’ acceptability of extruded pet food diet formulated without the use of preservative. Pet food diets contained beef meat bone meal (BMBM) and chicken byproduct meal (CBPM) in which the oxidation was retarded with ethoxyquin, mixed tocopherols, or none at all, and then extruded into dry pet foods. These samples represented low, medium, and high oxidation levels, respectively. Samples were stored for 0, 3, 6, 9, and 12 months at ambient temperature. Each time point, samples were evaluated by six highly

  10. A Catalase-related Hemoprotein in Coral Is Specialized for Synthesis of Short-chain Aldehydes: DISCOVERY OF P450-TYPE HYDROPEROXIDE LYASE ACTIVITY IN A CATALASE.

    Science.gov (United States)

    Teder, Tarvi; Lõhelaid, Helike; Boeglin, William E; Calcutt, Wade M; Brash, Alan R; Samel, Nigulas

    2015-08-01

    In corals a catalase-lipoxygenase fusion protein transforms arachidonic acid to the allene oxide 8R,9-epoxy-5,9,11,14-eicosatetraenoic acid from which arise cyclopentenones such as the prostanoid-related clavulones. Recently we cloned two catalase-lipoxygenase fusion protein genes (a and b) from the coral Capnella imbricata, form a being an allene oxide synthase and form b giving uncharacterized polar products (Lõhelaid, H., Teder, T., Tõldsepp, K., Ekins, M., and Samel, N. (2014) PloS ONE 9, e89215). Here, using HPLC-UV, LC-MS, and NMR methods, we identify a novel activity of fusion protein b, establishing its role in cleaving the lipoxygenase product 8R-hydroperoxy-eicosatetraenoic acid into the short-chain aldehydes (5Z)-8-oxo-octenoic acid and (3Z,6Z)-dodecadienal; these primary products readily isomerize in an aqueous medium to the corresponding 6E- and 2E,6Z derivatives. This type of enzymatic cleavage, splitting the carbon chain within the conjugated diene of the hydroperoxide substrate, is known only in plant cytochrome P450 hydroperoxide lyases. In mechanistic studies using (18)O-labeled substrate and incubations in H2(18)O, we established synthesis of the C8-oxo acid and C12 aldehyde with the retention of the hydroperoxy oxygens, consistent with synthesis of a short-lived hemiacetal intermediate that breaks down spontaneously into the two aldehydes. Taken together with our initial studies indicating differing gene regulation of the allene oxide synthase and the newly identified catalase-related hydroperoxide lyase and given the role of aldehydes in plant defense, this work uncovers a potential pathway in coral stress signaling and a novel enzymatic activity in the animal kingdom.

  11. Correction of Hypertension by Normalization of Endothelial Levels of Fibroblast Growth Factor and Nitric Oxide Synthase in Spontaneously Hypertensive Rats

    Science.gov (United States)

    Cuevas, Pedro; Garcia-Calvo, Margarita; Carceller, Fernando; Reimers, Diana; Zazo, Mercedes; Cuevas, Begona; Munoz-Willery, Isabel; Martinez-Coso, Victoria; Lamas, Santiago; Gimenez-Gallego, Guillermo

    1996-10-01

    Acidic and basic fibroblast growth factors (FGFs) share a wide range of diverse biological activities. To date, low levels of FGF have not been correlated with a pathophysiologic state. We report that blood vessels of spontaneously hypertensive rats are shown to be associated with a marked decrement in endothelial basic FGF content. This decrement correlates both with hypertension and with a decrease in the endothelial content of nitric oxide synthase. restoration of FGF to physiological levels in the vascular wall, either by systemic administration or by in vivo gene transfer, significantly augmented the number of endothelial cells with positive immunostaining for nitric oxide synthase, corrected hypertension, and ameliorated endothelial-dependent responses to vasoconstrictors. These results suggest an important role for FGFs in blood pressure homeostasis and open new avenues for the understanding of the etiology and treatment of hypertension.

  12. Mitochondrial DNA (mtDNA haplogroups and serum levels of anti-oxidant enzymes in patients with osteoarthritis

    Directory of Open Access Journals (Sweden)

    Fernandez-Moreno Mercedes

    2011-11-01

    Full Text Available Abstract Background Oxidative stress play a main role in the initiation and progression of the OA disease and leads to the degeneration of mitochondria. To prevent this, the chondrocytes possess a well-coordinated enzymatic antioxidant system. Besides, the mitochondrial DNA (mtDNA haplogroups are associated with the OA disease. Thus, the main goal of this work is to assess the incidence of the mtDNA haplogroups on serum levels of two of the main antioxidant enzymes, Manganese Superoxide Dismutase (Mn-SOD or SOD2 and catalase, and to test the suitability of these two proteins for potential OA-related biomarkers. Methods We analyzed the serum levels of SOD2 and catalase in 73 OA patients and 77 healthy controls carrying the haplogroups J, U and H, by ELISA assay. Knee and hip radiographs were classified according to Kellgren and Lawrence (K/L scoring from Grade 0 to Grade IV. Appropriate statistical analyses were performed to test the effects of clinical variables, including gender, body mass index (BMI, age, smoking status, diagnosis, haplogroups and radiologic K/L grade on serum levels of these enzymes. Results Serum levels of SOD2 appeared statistically increased in OA patients when compared with healthy controls (p Conclusions The increased levels of SOD2 in OA patients indicate an increased oxidative stress OA-related, therefore this antioxidant enzyme could be a suitable candidate biomarker for diagnosis of OA. Mitochondrial haplogroups significantly correlates with serum levels of catalase

  13. Effect of low glycemic index food and postprandial exercise on blood glucose level, oxidative stress and antioxidant capacity

    OpenAIRE

    糟谷, 憲明; 太田, 昌一郎; 髙波, 嘉一; Kawai, Yukari; 井上, 裕; 村田, 勇; 金本, 郁男

    2015-01-01

    Low glycemic index (GI) food and postprandial exercise are non?drug therapies for improving postprandial hyperglycemia. The present randomized, crossover study investigated the effect of low GI food combined with postprandial exercise on postprandial blood glucose level, oxidative stress and antioxidant capacity. A total of 13 healthy subjects were each used in four experiments: i) rice only (control), ii) salad prior to rice (LGI), iii) exercise following rice (EX) and iv) salad prior to ric...

  14. Effect of low glycemic index food and postprandial exercise on blood glucose level, oxidative stress and antioxidant capacity

    OpenAIRE

    KASUYA, NORIAKI; Ohta, Shoichiro; TAKANAMI, YOSHIKAZU; Kawai, Yukari; Inoue, Yutaka; MURATA, ISAMU; Kanamoto, Ikuo

    2015-01-01

    Low glycemic index (GI) food and postprandial exercise are non-drug therapies for improving postprandial hyperglycemia. The present randomized, crossover study investigated the effect of low GI food combined with postprandial exercise on postprandial blood glucose level, oxidative stress and antioxidant capacity. A total of 13 healthy subjects were each used in four experiments: i) rice only (control), ii) salad prior to rice (LGI), iii) exercise following rice (EX) and iv) salad prior to ric...

  15. Prenatal vitamin C deficiency results in differential levels of oxidative stress during late gestation in foetal guinea pig brains

    Directory of Open Access Journals (Sweden)

    Maya D. Paidi

    2014-01-01

    Full Text Available Antioxidant defences are comparatively low during foetal development making the brain particularly susceptible to oxidative stress during antioxidant deficiencies. The brain is one of the organs containing the highest concentration of vitamin C (VitC and VitC deficiency during foetal development may place the brain at risk of redox status imbalance. In the present study, we investigated the developmental pattern and effect of VitC deficiency on antioxidants, vitamin E and superoxide dismutase (SOD, assessed oxidative damage by measuring malondialdehyde (MDA, hydroxynonenal (HNE and nitrotyrosine (NT and analysed gene and protein expression of apoptosis marker caspase-3 in the guinea pig foetal brain at two gestational (GD time points, GD 45/pre-term and GD 56/near term following either a VitC sufficient (CTRL or deficient (DEF maternal dietary regime. We show that except for SOD, antioxidants and oxidative damage markers are differentially expressed between the two GDs, with high VitC (p<0.0001, NT modified proteins (p<0.0001 and active caspase-3 levels (p<0.05 at pre-term and high vitamin E levels (p<0.0001, HNE (p<0.0001 and MDA (p<0.0001 at near term. VitC deficiency significantly increased SOD activity (p<0.0001 compared to CTRLs at both GDs indicating a compensatory response, however, low levels of VitC significantly elevated MDA levels (p<0.05 in DEF at near term. Our results show a differential regulation of the investigated markers during late gestation and suggest that immature brains are susceptible to oxidative stress due to prenatal vitC deficiency in spite of an induction of protective adaptation mechanisms.

  16. Assessment of serum homocysteine, endothelin-1, and nitric oxide levels in behçet′s disease

    OpenAIRE

    Hodeib Abeer; Elsharawy Tarek; Fawzi Hisham

    2010-01-01

    Background: Some prominent features of Behηet′s disease (BD) are arterial and venous thromboses as a result of endothelial dysfunction. Hyperhomocysteinemia is responsible for vascular endothelial injury due to an increased frequency of thrombogenesis. Endothelin-1 (ET-1) is a vasoconstrictor whereas nitric oxide (NO) is an endothelial vasorelaxing peptide that is responsible for the inhibition of platelet adhesion. Aim: To evaluate serum levels of homocysteine (Hcy) and determine...

  17. Estimation and Comparison of Levels of Salivary Nitric Oxide in Patients with Oral Lichen Planus and Controls

    OpenAIRE

    Sapna Panjwani; Anjana Bagewadi; Vaishali Keluskar; Rohit Malik; Shalu Rai; Deepankar Misra

    2013-01-01

    Background: Normal salivary function is considered to be critical for the maintenance of healthy oral mucosa. Oral fluids provide an easily available, non-invasive medium for the diagnosis of wide range of diseases and clinical situations. The objective of this study was to estimate and compare salivary nitric oxide levels in patients with oral lichen planus and healthy individuals. Methods: Saliva was collected by spitting method. Unstimulated whole saliva thus collected was refrigerate...

  18. Estimation of salivary nitric oxide and uric acid levels in oral squamous cell carcinoma and healthy controls

    OpenAIRE

    Varsha Salian; Farah Demeri; Suchetha Kumari

    2015-01-01

    Background: Oral squamous cell carcinoma (OSCC) being the most common head and neck cancer, involves the interplay of several free radicals and antioxidant molecules. The potential role of salivary nitric oxide (NO) and uric acid in cancer development needs to be explored as there are a few studies highlighting their association with each other and with oral cancer. Aims: The present study was designed to measure the NO and uric acid levels in the saliva of patients with OSCC as compared with...

  19. Lignocellulose pretreatment technologies affect the level of enzymatic cellulose oxidation by LPMO

    DEFF Research Database (Denmark)

    Rodríguez-Zúñiga, Ursula Fabiola; Cannella, David; de Campos Giordano, Roberto;

    2015-01-01

    Sugarcane bagasse, corn stover, and wheat straw are among the most available resources for production of cellulosic ethanol. For these biomasses we study the influence of pre-treatment methods on the chemical composition, as well as on the subsequent reactions of enzymatic hydrolysis and oxidation...

  20. Leptin levels are associated with fat oxidation and dietary-induced weight loss in obesity

    DEFF Research Database (Denmark)

    Verdich, C; Toubro, S; Buemann, B;

    2001-01-01

    To examine the relationship between fasting plasma leptin and 24-hour energy expenditure (EE), substrate oxidation, and spontaneous physical activity (SPA) in obese subjects before and after a major weight reduction compared with normal weight controls. To test fasting plasma leptin, substrate...

  1. Nitric Oxide and Interlukin-6 Levels in Intellectual Disability Adults with Epilepsy

    Science.gov (United States)

    Carmeli, Eli; Beiker, Reut; Morad, Mohammed

    2009-01-01

    Nitric oxide (NO) and interlukin-6 (IL-6) are highly reactive mediators that have been shown to play different roles in a variety of different biological process. The role of NO and IL-6 in the neuropathogenesis of brain seizures is still questionable. In order to evaluate the role of NO and IL-6 in neurological disorders such as seizures, we…

  2. Some phenolic compounds increase the nitric oxide level in endothelial cells in vitro

    NARCIS (Netherlands)

    Appeldoorn, M.M.; Venema, D.P.; Peters, T.H.F.; Koenen, M.E.; Arts, I.C.W.; Vincken, J.-P.; Gruppen, H.; Keuer, J.; Hollman, P.C.H.

    2009-01-01

    The vasorelaxing properties of chocolate and wine might relate to the presence of phenolic compounds. One of the potential mechanisms involved is stimulation of endothelial nitric oxide (NO) production, as NO is a major regulator of vasodilatation. This study aimed to develop an in vitro assay using

  3. The higher level of organization of the oxidative phosphorylation system : mitochondrial supercomplexes

    NARCIS (Netherlands)

    Dudkina, Natalya V.; Sunderhaus, Stephanie; Boekema, Egbert J.; Braun, Hans-Peter

    2008-01-01

    The organization of the oxidative phosphorylation (OXPHOS) system within the inner mitochondrial membrane appears to be far more complicated than previously thought. In particular, the individual protein complexes of the OXPHOS system (complexes I to V) were found to specifically interact forming de

  4. Effect of age and eosinophil number on fractional exhaled nitric oxide level in non-asthmatic children in shanghai.

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2014-10-01

    Full Text Available This study aimed to identify the relationship between fractional exhaled nitric oxide (FeNO level and potential factors in non-asthmatic children from Shanghai, China. From March to April 2012, the school-aged children fulfilling the inclusion criteria were recruited. The FeNO levels of non-asthmatic children were detected by the Nano Coulomb nitric oxide analyzer. Questionnaires were recorded, including personal data, family illness history and daily habits. In addition, not only the number of leukocytes and eosinophils but also the level of hemoglobin in peripheral blood, were measured via the automated blood cell analyzer. All data were statistically analyzed with SPSS version 17.0 software and the correlation of these potential factors with FeNO level was calculated via Kendall's rank correlation. A total of 132 healthy children (aging 6-13 years were enrolled in Minhang District, Shanghai, China. The mean value of FeNO level was 15.05 ppb. The correlation analyses revealed that age (R=0.190, p=0.029 and eosinophil number (R=0.575, p=0.000 were significantly and positively correlated with FeNO levels. The FeNO levels of individuals aged 10-13 years was significantly higher than those of the individuals aged 6-9 years (22.65 ± 18.82 ppb vs. 15.28 ± 9.78 ppb, p<0.05. However, other potential factors were not significantly correlated with FeNO level. The FeNO levels in healthy school-aged children may reflect airway eosinophilic inflammation levels, and was affected by eosinophil count and age significantly.

  5. Oxidative stress and metabolic perturbations in Escherichia coli exposed to sublethal levels of 2,4-dichlorophenoxyacetic acid.

    Science.gov (United States)

    Bhat, Supriya V; Booth, Sean C; Vantomme, Erik A N; Afroj, Shirin; Yost, Christopher K; Dahms, Tanya E S

    2015-09-01

    The chlorophenoxy herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is used extensively worldwide despite its known toxicity and our limited understanding of how it affects non-target organisms. Escherichia coli is a suitable model organism to investigate toxicity and adaptation mechanisms in bacteria exposed to xenobiotic chemicals. We developed a methodical platform that uses atomic force microscopy, metabolomics and biochemical assays to quantify the response of E. coli exposed to sublethal levels of 2,4-D. This herbicide induced a filamentous phenotype in E. coli BL21 and a similar phenotype was observed in a selection of genotypically diverse E. coli strains (A0, A1, B1, and D) isolated from the environment. The filamentous phenotype was observed at concentrations 1000 times below field levels and was reversible upon supplementation with polyamines. Cells treated with 2,4-D had more compliant envelopes, significantly remodeled surfaces that were rougher and altered vital metabolic pathways including oxidative phosphorylation, the ABC transport system, peptidoglycan biosynthesis, amino acid, nucleotide and sugar metabolism. Most of the observed effects could be attributed to oxidative stress, consistent with increases in reactive oxygen species as a function of 2,4-D exposure. This study provides direct evidence that 2,4-D at sublethal levels induces oxidative stress and identifies the associated metabolic changes in E. coli.

  6. Comparison of the Salivary and the Serum Nitric Oxide Levels in Chronic and Aggressive Periodontitis: A Biochemical Study

    Science.gov (United States)

    Sundar, N. Mani; Krishnan, V; Krishnaraj, S; Hemalatha, V.T.; Alam, Md Nazish

    2013-01-01

    Background and Objectives: Nitric oxide (NO) is a ubiquitous intercellular messenger molecule with important cardiovascular, neurological, and immune functions. In addition, it has been postulated that the pharmacological inhibition of NO or its actions may be therapeutically valuable in the disease management. The levels of nitric oxide may provide clues about the severity and the state of the underlying disease process. It could be an inflammatory biomarker that may enable clinicians to direct the environmentally based prevention or treatment programmes and to establish whether NO plays a role in the pathogenesis of periodontitis or not. Hence, the aim of the present study was to evaluate the salivary and the serum levels of NO in generalized chronic and aggressive periodontitis. The Study Design: Unstimulated whole saliva and serum samples were collected from a total of 60 subjects who were in the age group of 18-45 years, who participated in this study. They were divided into three equal groups with 20 subjects in each group; group A (healthy controls), group B (chronic periodontitis) and group C (aggressive periodontitis). The clinical parameters were assessed, based on the oral hygiene index simplified (OHI-S), the gingival index (GI), the probing pocket depth and the clinical attachment loss (CAL). A biochemical analysis was performed to evaluate and compare the salivary and the serum nitric oxide levels of the above groups. Statistical Analysis and Results: The statistical comparisons were done under the Griess Reaction. There were statistically significant salivary and serum levels of NO in the groups of periodontitis (group B and C) as compared to those in the healthy controls (group A). A significant positive correlation was found between the values of the salivary and the serum NO levels in chronic and aggressive periodontitis. Conclusion: Nitric oxide is a potent modulator of the inflammatory disease processes and under pathological conditions, NO has

  7. Accumulation of Oxidized Low-Density Lipoprotein in Psoriatic Skin and Changes of Plasma Lipid Levels in Psoriatic Patients

    Directory of Open Access Journals (Sweden)

    Nilgun Solak Tekin

    2007-01-01

    Full Text Available Background. Psoriasis is a chronic inflammatory skin disease characterized by an accelerated turnover of epidermal cells and an incomplete differentiation in epidermis with lesion. However, the exact etiology of psoriasis is unknown. Abnormalities in essential fatty acid metabolism, free radical generation, lipid peroxidation, and release of lymphokines have been proposed. Objective. Our purpose was to evaluate the plasma lipids and oxidized low-density lipoprotein accumulation in psoriatic skin lesion in order to ascertain the possible participation of oxidative stress and oxidative modification of lipids in pathogenesis of psoriasis. Methods. The study group included 84 patients with psoriasis, and 40 sex- and age-matched healthy volunteers. Blood lipid profile was determined. Psoriatic and nonlesional skin samples of psoriatic patients were evaluated for the presence of oxidized low-density lipoprotein by using an immune-fluorescent staining method. Results. The mean levels of lipids (total cholesterol, triglyceride, and LDL cholesterol in patients with psoriasis were found to be significantly higher than those of healthy subjects. Psoriatic skins were shown positive oxidized low-density lipoprotein staining. There was no staining in nonlesional skin samples of the same individuals. Conclusion. Lipid peroxidation mediated by free radicals is believed to be one of the important causes of cell membrane destruction and cell damage. This study shows for the first time the accumulation of oxidized low-density lipoprotein in psoriatic skin lesion. We believe that accumulation of ox-LDL in psoriatic skin may have an important role in the immune-inflammatory events that result in progressive skin damage.

  8. The Impact of Rendered Protein Meal Oxidation Level on Shelf-Life, Sensory Characteristics, and Acceptability in Extruded Pet Food.

    Science.gov (United States)

    Chanadang, Sirichat; Koppel, Kadri; Aldrich, Greg

    2016-01-01

    Pet foods are expected to have a shelf-life for 12 months or more. Sensory analysis can be used to determine changes in products and to estimate products' shelf-life. The objectives of this study were to (1) investigate how increasing levels of oxidation in rendered protein meals used to produce extruded pet food affected the sensory properties and (2) determine the effect of shelf-life on pet owners' acceptability of extruded pet food diet formulated without the use of preservative. Pet food diets contained beef meat bone meal (BMBM) and chicken byproduct meal (CBPM) in which the oxidation was retarded with ethoxyquin, mixed tocopherols, or none at all, and then extruded into dry pet foods. These samples represented low, medium, and high oxidation levels, respectively. Samples were stored for 0, 3, 6, 9, and 12 months at ambient temperature. Each time point, samples were evaluated by six highly trained descriptive panelists for sensory attributes related to oxidation. Samples without preservatives were chosen for the acceptability test, since the differences in sensory characteristics over storage time were more distinguishable in those samples. Pet owners evaluated samples for aroma, appearance and overall liking. Descriptive sensory analysis detected significant changes in oxidized-related sensory characteristics over storage time. However, the differences for CBPM samples were more pronounced and directional. The consumer study showed no differences in pet owners' acceptability for BMBM samples. However, the noticeable increase in aroma characteristics (rancid aroma 0.33-4.21) in CBPM samples over storage time did have a negative effect on consumer's liking (overall liking 5.52-4.95). PMID:27483326

  9. Iodine-Catalyzed Prins Cyclization of Homoallylic Alcohols and Aldehydes

    Directory of Open Access Journals (Sweden)

    Luiz F. Silva

    2013-09-01

    Full Text Available The iodine-catalyzed Prins cyclization of homoallylic alcohols and aldehydes was investigated under metal-free conditions and without additives. Anhydrous conditions and inert atmosphere are not required. The reaction of 2-(3,4-dihydronaphthalen-1-ylpropan-1-ol and 21 aldehydes (aliphatic and aromatic in CH2Cl2 in the presence of 5 mol % of iodine gave 1,4,5,6-tetrahydro-2H-benzo[f]isochromenes in 54%–86% yield. Under similar conditions, the Prins cyclization of six alcohols containing an endocyclic double bond (primary, secondary, or tertiary led to dihydropyrans in 52%–91% yield. The acyclic homoallylic alcohols gave 4-iodo-tetrahydropyran in 29%–41% yield in the presence of 50 mol % of iodine. This type of substrate is the main limitation of the methodology. The relative configuration of the products was assigned by NMR and X-ray analysis. The mechanism and the ratio of the products are discussed, based on DFT calculations.

  10. Aldehyde dehydrogenase 1a3 defines a subset of failing pancreatic β cells in diabetic mice.

    Science.gov (United States)

    Kim-Muller, Ja Young; Fan, Jason; Kim, Young Jung R; Lee, Seung-Ah; Ishida, Emi; Blaner, William S; Accili, Domenico

    2016-01-01

    Insulin-producing β cells become dedifferentiated during diabetes progression. An impaired ability to select substrates for oxidative phosphorylation, or metabolic inflexibility, initiates progression from β-cell dysfunction to β-cell dedifferentiation. The identification of pathways involved in dedifferentiation may provide clues to its reversal. Here we isolate and functionally characterize failing β cells from various experimental models of diabetes and report a striking enrichment in the expression of aldehyde dehydrogenase 1 isoform A3 (ALDH(+)) as β cells become dedifferentiated. Flow-sorted ALDH(+) islet cells demonstrate impaired glucose-induced insulin secretion, are depleted of Foxo1 and MafA, and include a Neurogenin3-positive subset. RNA sequencing analysis demonstrates that ALDH(+) cells are characterized by: (i) impaired oxidative phosphorylation and mitochondrial complex I, IV and V; (ii) activated RICTOR; and (iii) progenitor cell markers. We propose that impaired mitochondrial function marks the progression from metabolic inflexibility to dedifferentiation in the natural history of β-cell failure. PMID:27572106

  11. Low level and sub-chronic exposure to methylmercury induces hypertension in rats: nitric oxide depletion and oxidative damage as possible mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Grotto, Denise; Barcelos, Gustavo R.M.; Barbosa, Fernando [Universidade de Sao Paulo, Departamento de Analises Clinicas, Toxicologicas e Bromatologicas, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto, Ribeirao Preto, SP (Brazil); Castro, Michele M. de [Universidade de Sao Paulo, Departamento de Farmacologia, Faculdade de Medicina de Ribeirao Preto, Ribeirao Preto, SP (Brazil); Garcia, Solange C. [Universidade Federal de Santa Maria, Departamento de Analises Clinicas e Toxicologicas, Santa Maria, Rio Grande do Sul (Brazil)

    2009-07-15

    Increased risk of hypertension after methylmercury (MeHg) exposure has been suggested. However, the underlying mechanisms are not well explored. In this paper, we have analyzed whether sub-chronic exposure to MeHg increases systolic blood pressure even at very low levels. In addition, we analyzed if the methylmercury-induced hypertension is associated with a decreased plasmatic nitric oxide levels and with a dysregulation of the activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), as well as the levels of MDA and glutathione. For this study, Wistar rats were treated with methylmercury chloride (100 {mu}g/kg per day) or vehicle. Total treatment time was 100 days. Malondialdehyde (MDA) and circulating NOx levels and superoxide dismutase (SOD) and catalase (CAT) activities were determined in plasma, whereas glutathione levels were determined in erythrocytes. Our results show that long-term treatment at a low level of MeHg affected systolic blood pressure, increasing and reducing the levels of plasmatic MDA and NOx, respectively. However, the activity of SOD did not decrease in the MeHg exposed group when compared to the control. We found a negative correlation between plasmatic nitrite/nitrate (NOx) levels and systolic blood pressure (r=-0.67; P=0.001), and a positive correlation between MDA and systolic blood pressure (r=0.61; P=0.03), thus suggesting increased inhibition of NO formation with the increase of hypertension. In conclusion, long-term exposure to a low dose of MeHg increases the systolic pressure and is associated, at least in part, with increased production of ROS as judged by increased production of malondialdehyde and depressed NO availability. (orig.)

  12. Tolerance of spermatogonia to oxidative stress is due to high levels of Zn and Cu/Zn superoxide dismutase.

    Directory of Open Access Journals (Sweden)

    Fritzie T Celino

    Full Text Available BACKGROUND: Spermatogonia are highly tolerant to reactive oxygen species (ROS attack while advanced-stage germ cells such as spermatozoa are much more susceptible, but the precise reason for this variation in ROS tolerance remains unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using the Japanese eel testicular culture system that enables a complete spermatogenesis in vitro, we report that advanced-stage germ cells undergo intense apoptosis and exhibit strong signal for 8-hydroxy-2'-deoxyguanosine, an oxidative DNA damage marker, upon exposure to hypoxanthine-generated ROS while spermatogonia remain unaltered. Activity assay of antioxidant enzyme, superoxide dismutase (SOD and Western blot analysis using an anti-Copper/Zinc (Cu/Zn SOD antibody showed a high SOD activity and Cu/Zn SOD protein concentration during early spermatogenesis. Immunohistochemistry showed a strong expression for Cu/Zn SOD in spermatogonia but weak expression in advanced-stage germ cells. Zn deficiency reduced activity of the recombinant eel Cu/Zn SOD protein. Cu/Zn SOD siRNA decreased Cu/Zn SOD expression in spermatogonia and led to increased oxidative damage. CONCLUSIONS/SIGNIFICANCE: These data indicate that the presence of high levels of Cu/Zn SOD and Zn render spermatogonia resistant to ROS, and consequently protected from oxidative stress. These findings provide the biochemical basis for the high tolerance of spermatogonia to oxidative stress.

  13. The effect of oxidative stress on human red cells glutathione peroxidase, glutathione reductase level, and prevalence of anemia among diabetics

    Directory of Open Access Journals (Sweden)

    Hisham Waggiallah

    2011-01-01

    Full Text Available Background: The oxidative stress is considered as major consequence of diabetes mellitus affecting red cell antioxidant enzymes. Aim: The present study was conducted to assess the impact of oxidative stress (reduced glutathione on glutathione peroxidase, and glutathione reductse and prevalence of anemia among diabetic patients. Materials and Methods: The study involved 100 adult patients attending Buraidah Central Hospital and 30 healthy controls. Blood samples were collected and analyzed for glutathione (GSH concentration, glutathione peroxidase (GPO, glutathione reductase (GR, fasting blood sugar (RBS, hemoglobin (HGB, red cell count (RBCs hematocrit (HCT mean cell volume (MCV mean cell hemoglobin (MCH and mean cell hemoglobin concentration (MCHC and hemoglobin A1c. Blood urea, serum creatinine, and microalbuminuria were measured to exclude diabetes mellitus nephropathy. Results : were obtained showed significant correlation between deficiency of glutathione peroxidase, glutathione reductase and deficient of glutathione among diabetics, which has significant correlation between low hemoglobin concentration (females <120 g/L, males <130 g/L, also there is low concentration of red cell count and red cell indices (MCV, MCH and MCHC. The prevalence of anemia was 22% in diabetes patients. Conclusion: It can be concluded that there is strong significant effect of oxidative stress (reduced glutathione on glutathione peroxidase, glutathione reductase level these may reduce hemoglobin concentration in diabetic patients. This means oxidative stress of diabetes mellitus is the possible cause of anemia in diabetics without nephropathy.

  14. Engineering the Mechanical Properties of Monolayer Graphene Oxide at the Atomic Level.

    Science.gov (United States)

    Soler-Crespo, Rafael A; Gao, Wei; Xiao, Penghao; Wei, Xiaoding; Paci, Jeffrey T; Henkelman, Graeme; Espinosa, Horacio D

    2016-07-21

    The mechanical properties of graphene oxide (GO) are of great importance for applications in materials engineering. Previous mechanochemical studies of GO typically focused on the influence of the degree of oxidation on the mechanical behavior. In this study, using density functional-based tight binding simulations, validated using density functional theory simulations, we reveal that the deformation and failure of GO are strongly dependent on the relative concentrations of epoxide (-O-) and hydroxyl (-OH) functional groups. Hydroxyl groups cause GO to behave as a brittle material; by contrast, epoxide groups enhance material ductility through a mechanically driven epoxide-to-ether functional group transformation. Moreover, with increasing epoxide group concentration, the strain to failure and toughness of GO significantly increases without sacrificing material strength and stiffness. These findings demonstrate that GO should be treated as a versatile, tunable material that may be engineered by controlling chemical composition, rather than as a single, archetypical material. PMID:27356465

  15. Elevated levels of urinary markers of oxidatively generated DNA and RNA damage in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Poulsen, Henrik Enghusen; Kessing, Lars Vedel;

    2015-01-01

    investigated oxidatively generated damage to DNA and RNA in patients with bipolar disorder and its relationship with the affective phase compared with healthy control subjects. METHODS: Urinary excretion of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo), markers...... of oxidatively generated DNA and RNA damage, respectively, was measured in 37 rapid cycling patients with bipolar disorder and in 40 age- and gender-matched healthy control subjects. Employing a longitudinal design, repeated measurements of both markers were evaluated in various affective phases in patients...... with bipolar disorder during a six- to 12-month period and compared with repeated measurements in healthy control subjects. RESULTS: In linear mixed models, adjusting for demographical, metabolic, and lifestyle factors, the excretion of 8-oxodG and 8-oxoGuo was significantly elevated in euthymic patients...

  16. Modeling and Simulations in Photoelectrochemical Water Oxidation: From Single Level to Multiscale Modeling.

    Science.gov (United States)

    Zhang, Xueqing; Bieberle-Hütter, Anja

    2016-06-01

    This review summarizes recent developments, challenges, and strategies in the field of modeling and simulations of photoelectrochemical (PEC) water oxidation. We focus on water splitting by metal-oxide semiconductors and discuss topics such as theoretical calculations of light absorption, band gap/band edge, charge transport, and electrochemical reactions at the electrode-electrolyte interface. In particular, we review the mechanisms of the oxygen evolution reaction, strategies to lower overpotential, and computational methods applied to PEC systems with particular focus on multiscale modeling. The current challenges in modeling PEC interfaces and their processes are summarized. At the end, we propose a new multiscale modeling approach to simulate the PEC interface under conditions most similar to those of experiments. This approach will contribute to identifying the limitations at PEC interfaces. Its generic nature allows its application to a number of electrochemical systems.

  17. Effect of antioxidants and antibiotics on levels of seminal oxidative stress in leukocytospermic infertile men

    OpenAIRE

    Yadav, Sunil B.; Adinath N. Suryakar; Huddedar, Anil D.; Shukla, Pramod S.

    2006-01-01

    Defective sperm function is the most common cause of infertility. A prospective study was carried out to correlate the concentration of nitrite (the stable metabolite of nitric oxide) in seminal plasma with leukocytospermia, and sperm membrane integrity. Total Fifty-seven normozoospermic subjects with and without leukocytospermia visiting the Infertility clinic at KH and MRC, Karad, were included in the present study. Semen samples were checked for sperm concentration, total sperm count, sper...

  18. Reduced Levels of Nitric Oxide Metabolites in Cerebrospinal Fluid Are Associated with Equine Protozoal Myeloencephalitis

    OpenAIRE

    Njoku, Chinedu J.; Saville, William J. A.; Reed, Stephen M.; Oglesbee, Michael J.; Rajala-Schultz, Päivi J.; Stich, Roger W

    2002-01-01

    Equine protozoal myeloencephalitis (EPM) is a disease of horses that is primarily associated with infection with the apicomplexan Sarcocystis neurona. Infection with this parasite alone is not sufficient to induce the disease, and the mechanism of neuropathogenesis associated with EPM has not been reported. Nitric oxide (NO) functions as a neurotransmitter, a vasodilator, and an immune effector and is produced in response to several parasitic protozoa. The purpose of this work was to determin...

  19. Association of indoor air pollution with rhinitis symptoms, atopy and nitric oxide levels in exhaled air

    DEFF Research Database (Denmark)

    Hersoug, Lars-Georg; Husemoen, Lise Lotte N; Thomsen, Simon Francis;

    2010-01-01

    Exposure to particulate matter (PM) outdoors can induce airway inflammation and exacerbation of asthma in adults. However, there is limited knowledge about the effects of exposure to indoor PM. The aim of this study was to investigate the association of exposure to indoor sources of PM with rhini...... with rhinitis symptoms, atopy and nitric oxide in exhaled air (FeNO) as a measure of airway inflammation....

  20. PLASMA AND ERYTHROCYTE NITRIC OXIDE LEVELS IN EPILEPTIC CHILDREN RECEIVING LONG-TERM SODIUM VALPROATE THERAPY

    OpenAIRE

    ÖZEROL, Elif; ÖZEROL, İbrahim; Aslan, Mehmet; GÜLEÇ, Mukaddes; YAKINCI, Cengiz; AKYOL, ÖMER

    2003-01-01

    Valproate (VPA) is a widely used drug as the first-line treatment for epilepsy in children. Nitric oxide (NO) is an important intercellular physiological messenger capable of evoking a number of cellular responses. It is generally believed that the erytrocyte membrane is highly permeable to NO. It has been claimed that VPA may show its antiepileptic effect throughout NO. Therefore, the aim of our study were to evaluate whether differences exist in the plasma and erythrocyte NO concentrati...

  1. Exhaled nitric oxide levels in childhood asthma: a more reliable indicator of asthma severity than lung function measurement?

    Science.gov (United States)

    Piacentini, G L; Suzuki, Y; Bodini, A

    2000-04-01

    The level of exhaled nitric oxide (NO) has been demonstrated to reflect the degree of airway inflammation in patients with asthma and to be related to the severity of asthma, as well as to the efficacy of treatment. In contrast, lung function tests provide information about airway volumes and flows reflecting the level of airway obstruction, but do not allow any direct information about the degree of airway inflammation. Several studies have evaluated the relationships between the level of airway inflammation assessed by exhaled NO and the levels of airway obstruction and/or bronchial hyperresponsiveness in asthmatic adults and children. These studies highlight the complex pathophysiology of asthma and suggest that exhaled NO may have a promising role in addition to lung function measurement in the evaluation of asthma severity in children. PMID:18034534

  2. A Novel NADPH-Dependent Aldehyde Reductase Gene from Saccharomyces cerevisiae NRRL Y-12632 Involved in the Detoxification of Aldehyde Inhibitors Derived from Lignocellulosic Biomass Conversion

    Science.gov (United States)

    Aldehyde inhibitors such as furfural, 5-hydroxymethylfurfural (HMF), anisaldehyde, benzaldehyde, cinnamaldehyde, and phenylaldehyde are commonly generated during lignocellulosic biomass conversion process for low-cost cellulosic ethanol production that interferes with subsequent microbial growth and...

  3. Effects of exogenous vitamin E supplementation on the levels of oxidants and antioxidants in chronic obstructive pulmonary disease

    Indian Academy of Sciences (India)

    M K Daga; Rashmi Chhabra; Bhavneesh Sharma; T K Mishra

    2003-02-01

    Oxidative stress has been recognized as a central feature of smoke induced chronic obstructive pulmonary disease (COPD). Imbalance between oxidant and antioxidant enzymes is also an established fact in these patients. But studies in regard to stable COPD patients and effect of vitamin E supplementation are lacking. Thirty patients with COPD were included in the study. Their baseline clinical examination, spirometry, plasma malondialdehyde (MDA), alpha-tocopherol and red blood cell superoxide dismutase (SOD) levels were measured. Twenty healthy non-smokers who were matched for age and sex served as controls. All the above parameters were repeated after 12 weeks of supplementation with 400 IU of vitamin E daily. The mean malondialdehyde levels in the patients at baseline were higher than controls (5.91 ± 1.23 nmol/ml vs 4.55 ± 1.51 nmol/ml, = 0.001), so also was plasma alpha-tocopherol levels ( < 0.001), while SOD levels were lower in the patients compared to controls (1692 ± 259 units g/Hb vs 2451 ± 131 units g/Hb, < 0.001). Exogenous vitamin E (400 IU per day) supplementation did not bring about any significant change in plasma alpha-tocopherol and SOD levels. The Pearson’s co-efficient of correlation between the levels of MDA, vitamin E, SOD; and spirometric measurements were not significant either on day 1 or after 12 weeks of vitamin E supplementation. The present study shows that initially the plasma lipid peroxide (MDA) levels are high and antioxidants (alpha-tocopherol and SOD) are low in patients with COPD. Exogenous supplementation with vitamin E does not have any significant effect on the spirometric measurements though it brings down the levels of MDA showing attenuation of further damage. However, inclusion of larger number of patients and supplementation with vitamin E for longer periods may throw more light on free radical injury and protective effects of antioxidants.

  4. The effect of endometritis on level of inflammatory protein and oxidation factor via NF-κB signal pathway

    Institute of Scientific and Technical Information of China (English)

    Ming Ni

    2015-01-01

    Objective:This study explored effect of endometritis induced by LPS on level of inflammatory protein and oxidation factor via NF-κB signal pathway.Methods: Endometial cell was treated with LPS (50, 100, 200 ng/mL). The viability of cell was detected by MTT assay. The concentration of IL-6 and PGE2 was tested by elisa method. The concentration of MDA was tested by thiobarbituric acid method. The concentration of SOD was tested by xanthine oxidation method. The concentration of NO was tested by Gries method. The expression of NF-κB p65 was assayed by western blot.Results:MTT assay demonstrated LPS (50, 100, 00 ng/mL) could suppress cell viability, and the inhibitory effect was highest in 48 h. With the increasing dose of LPS, the activity of SOD decreased, the level of MDA, NO, IL-1 and PGE2 elevated. Finally, LPS stimulated NF-κB p65 phosphorylation.Conclusion:These results suggested endometrial cell treated by LPS make inflammatory factor secreted and anti-oxidant ability decreased, which might be related to NF-κB signal pathway.

  5. The effect of CAPE on lipid peroxidation and nitric oxide levels in the plasma of rats following thermal injury.

    Science.gov (United States)

    Hoşnuter, Mübin; Gürel, Ahmet; Babucçu, Orhan; Armutcu, Ferah; Kargi, Eksal; Işikdemir, Ahmet

    2004-03-01

    Both experimental and clinical studies have shown that oxygen-derived free radicals rise in the plasma after thermal injury and participate in the pathogenesis of tissue damage. Hence, various antioxidant molecules have been used in treatment of burn injury both experimentally and clinically. Caffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, is known to have potent antioxidant property. The purpose of the present study was to investigate the effects of CAPE on oxidative stress in plasma of burned rats. Experiment was designed in three groups of rats with 20% full-thickness burn: (a) sham burn (n = 7); (b) burn only (n = 22); (c) burn + treatment with CAPE (n = 22). Plasma levels of malondialdehyde (MDA), nitric oxide (NO) and the activities of xanthine oxidase (XO), and superoxide dismutase (SOD) were used as both bio-indicators of oxidant status and determinant of antioxidant effect of CAPE. They were assessed by biochemical methods at 1st, 3rd, 7th, and 14th post-burn days. In conclusion, CAPE was shown to possess antioxidant activity by saving SOD activity, preventing XO activity and decreasing the levels of MDA, and NO. Our study showed that CAPE may be beneficial in burn injury.

  6. Threshold responses in cinnamic-aldehyde-sensitive subjects: results and methodological aspects

    DEFF Research Database (Denmark)

    Johansen, J D; Andersen, Klaus Ejner; Rastogi, S C;

    1996-01-01

    Cinnamic aldehyde is an important fragrance material and contact allergen. The present study was performed to provide quantitative data on the eliciting capacity of cinnamic aldehyde, to be considered in assessment of clinical relevance and health hazard. The skin response to serial dilution patc...

  7. Direct chemoselective synthesis of glyconanoparticles from unprotected reducing glycans and glycopeptide aldehydes

    DEFF Research Database (Denmark)

    Thygesen, Mikkel Boas; Sørensen, Kasper Kildegaard; Cló, Emiliano;

    2009-01-01

    Chemoselective oxime coupling was used for facile conjugation of unprotected, reducing glycans and glycopeptide aldehydes with core-shell gold nanoparticles carrying reactive aminooxy groups on the organic shell.......Chemoselective oxime coupling was used for facile conjugation of unprotected, reducing glycans and glycopeptide aldehydes with core-shell gold nanoparticles carrying reactive aminooxy groups on the organic shell....

  8. Draft Genome Sequence of Aldehyde-Degrading Strain Halomonas axialensis ACH-L-8

    OpenAIRE

    Ye, Jun; Ren, Chong; Shan, Xiexie; Zeng, Runying

    2016-01-01

    Halomonas axialensis ACH-L-8, a deep-sea strain isolated from the South China Sea, has the ability to degrade aldehydes. Here, we present an annotated draft genome sequence of this species, which could provide fundamental molecular information on the aldehydes-degrading mechanism.

  9. Draft Genome Sequence of Aldehyde-Degrading Strain Halomonas axialensis ACH-L-8.

    Science.gov (United States)

    Ye, Jun; Ren, Chong; Shan, Xiexie; Zeng, Runying

    2016-01-01

    Halomonas axialensisACH-L-8, a deep-sea strain isolated from the South China Sea, has the ability to degrade aldehydes. Here, we present an annotated draft genome sequence of this species, which could provide fundamental molecular information on the aldehydes-degrading mechanism. PMID:27081145

  10. Potential Association of Lead Exposure During Early Development of Mice With Alteration of Hippocampus Nitric Oxide Levels and Learning Memory

    Institute of Scientific and Technical Information of China (English)

    LI SUN; ZHENG-YAN ZHAO; JIAN HU; XIE-LAI ZHOU

    2005-01-01

    Objective Chronic lead (Pb) exposure during development is known to produce learning deficits. Nitric oxide participates in the synaptic mechanisms involved in certain forms of learning and memory. This study was designed to clarify whether Pb-induced impairment in learning and memory was associated with the changes of nitric oxide levels in mice brains.Methods Sixty Balb/c mice aged 10 days were chosen. A model of lead exposure was established by drinking 0.025%, 0.05%,0.075% lead acetate, respectively for 8 weeks. The controls were orally given distilled water. The ability to learn and memorize was examined by open field test, T-water maze test. In parallel with the behavioral data, NO level of hippocampus tissue was detected by biochemical assay. Results Compared with control groups, (1) the weight of 0.075% group was significantly reduced (P<0.05); (2) The number of times in mice attaining the required standards in T-water maze test was lower in 0.075%group (P<0.01). No significant difference was found between experimental and control groups in open field test (P>0.05); (3)NO level of mouse hippocampus tissue was decreased in 0.075% group (P<0.01). Conclusions The findings suggest that decreased hippocampus NO level may contribute to the Pb-induced deficits in learning and memory processes.

  11. Combination of nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy as a novel therapeutic application to manage the pain and treat many clinical conditions

    Science.gov (United States)

    Halasa, Salaheldin; Dickinson, Eva

    2014-02-01

    From hypertension to diabetes, cancer to HIV, stroke to memory loss and learning disorders to septic shock, male impotence to tuberculosis, there is probably no pathological condition where nitric oxide does not play an important role. Nitric oxide is an analgesic, immune-modulator, vasodilator, anti-apoptotic, growth modulator, angiogenetic, anti-thrombotic, anti-inflammatory and neuro-modulator. Because of the above actions of nitric oxide, many clinical conditions associated with abnormal Nitric oxide (NO) production and bioavailability. Our novel therapeutic approach is to restore the homeostasis of nitric oxide and replace the lost cells by combining nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy.

  12. Effects of ethanol on CYP2E1 levels and related oxidative stress using a standard balanced diet.

    Science.gov (United States)

    Azzalis, Ligia A; Fonseca, Fernando L A; Simon, Karin A; Schindler, Fernanda; Giavarotti, Leandro; Monteiro, Hugo P; Videla, Luis A; Junqueira, Virgínia B C

    2012-07-01

    Expression of cytochrome P4502E1 (CYP2E1) is very much influenced by nutritional factors, especially carbohydrate consumption, and various results concerning the expression of CYP2E1 were obtained with a low-carbohydrate diet. This study describes the effects of ethanol treatment on CYP2E1 levels and its relationship with oxidative stress using a balanced standard diet to avoid low or high carbohydrate consumption. Rats were fed for 1, 2, 3, or 4 weeks a commercial diet plus an ethanol-sucrose solution. The results have shown that ethanol administration was associated with CYP2E1 induction and stabilization without related oxidative stress. Our findings suggest that experimental models with a low-carbohydrate/high-fat diet produce some undesirable CYP2E1 changes that are not present when a balanced standard diet is given.

  13. Correlation of plasma nitrite/nitrate levels and inducible nitric oxide gene expression among women with cervical abnormalities and cancer.

    Science.gov (United States)

    Sowjanya, A Pavani; Rao, Meera; Vedantham, Haripriya; Kalpana, Basany; Poli, Usha Rani; Marks, Morgan A; Sujatha, M

    2016-01-30

    Cervical cancer is caused by infection with high risk human papillomavirus (HR-HPV). Inducible nitric oxide synthase (iNOS), a soluble factor involved in chronic inflammation, may modulate cervical cancer risk among HPV infected women. The aim of the study was to measure and correlate plasma nitrite/nitrate levels with tissue specific expression of iNOS mRNA among women with different grades of cervical lesions and cervical cancer. Tissue biopsy and plasma specimens were collected from 120 women with cervical neoplasia or cancer (ASCUS, LSIL, HSIL and invasive cancer) and 35 women without cervical abnormalities. Inducible nitric oxide synthase (iNOS) mRNA from biopsy and plasma nitrite/nitrate levels of the same study subjects were measured. Single nucleotide polymorphism (SNP) analysis was performed on the promoter region and Ser608Leu (rs2297518) in exon 16 of the iNOS gene. Differences in iNOS gene expression and plasma nitrite/nitrate levels were compared across disease stage using linear and logistic regression analysis. Compared to normal controls, women diagnosed with HSIL or invasive cancer had a significantly higher concentration of plasma nitrite/nitrate and a higher median fold-change in iNOS mRNA gene expression. Genotyping of the promoter region showed three different variations: A pentanucleotide repeat (CCTTT) n, -1026T > G (rs2779249) and a novel variant -1153T > A. These variants were associated with increased levels of plasma nitrite/nitrate across all disease stages. The higher expression of iNOS mRNA and plasma nitrite/nitrate among women with pre-cancerous lesions suggests a role for nitric oxide in the natural history of cervical cancer. PMID:26435258

  14. On-site evaluation of crud build-up and clad oxidation level

    International Nuclear Information System (INIS)

    The general trend in the late 1980's is to move toward longer operating cycles and extended burn-up. Among the questions raised by this increased performance PWR's waterside corrosion could be a potentially life-limiting problem. Therefore a large on site surveillance programme has been set up to collect data in various conditions: different plants and cycles, local burn-up up to 60 GWd/MTU, load follow operation, nucleate boiling... For that purpose FRAGEMA has developed a simple device, which can be easily installed in the spent fuel pit, featuring jointly a crud scrapping system and an Eddy-current probe for oxide thickness measurements: this makes possible correlation between clad corrosion and crud thickness. A telescopic pole is hanged along the wall of the pit, an X-Y carriage allows its movement in two perpendicular directions. At the bottom part either a scrapping head or an Eddy-current probe can be mounted. Both selection of the areas to be examined and monitoring during scrapping and measurements are made with the help of a T.V. camera. Design of the tool has been focused on safety aspect to avoid any deterioration of the fuel assembly and to minimize radiation exposure during crud collection and filtration. The positioning and the touching of the eddy-current probe on the rod have been carefully studied to ensure reliable data collection. For calibration, oxidized zircaloy tubes with well known oxide thickness, are used. Detailed description of the complete device and experience obtained through several campaigns are presented in this paper. (author)

  15. Amino Acid Residues Critical for the Specificity for Betaine Aldehyde of the Plant ALDH10 Isoenzyme Involved in the Synthesis of Glycine Betaine1[W][OA

    Science.gov (United States)

    Díaz-Sánchez, Ángel G.; González-Segura, Lilian; Mújica-Jiménez, Carlos; Rudiño-Piñera, Enrique; Montiel, Carmina; Martínez-Castilla, León P.; Muñoz-Clares, Rosario A.

    2012-01-01

    Plant Aldehyde Dehydrogenase10 (ALDH10) enzymes catalyze the oxidation of ω-primary or ω-quaternary aminoaldehydes, but, intriguingly, only some of them, such as the spinach (Spinacia oleracea) betaine aldehyde dehydrogenase (SoBADH), efficiently oxidize betaine aldehyde (BAL) forming the osmoprotectant glycine betaine (GB), which confers tolerance to osmotic stress. The crystal structure of SoBADH reported here shows tyrosine (Tyr)-160, tryptophan (Trp)-167, Trp-285, and Trp-456 in an arrangement suitable for cation-π interactions with the trimethylammonium group of BAL. Mutation of these residues to alanine (Ala) resulted in significant Km(BAL) increases and Vmax/Km(BAL) decreases, particularly in the Y160A mutant. Tyr-160 and Trp-456, strictly conserved in plant ALDH10s, form a pocket where the bulky trimethylammonium group binds. This space is reduced in ALDH10s with low BADH activity, because an isoleucine (Ile) pushes the Trp against the Tyr. Those with high BADH activity instead have Ala (Ala-441 in SoBADH) or cysteine, which allow enough room for binding of BAL. Accordingly, the mutation A441I decreased the Vmax/Km(BAL) of SoBADH approximately 200 times, while the mutation A441C had no effect. The kinetics with other ω-aminoaldehydes were not affected in the A441I or A441C mutant, demonstrating that the existence of an Ile in the second sphere of interaction of the aldehyde is critical for discriminating against BAL in some plant ALDH10s. A survey of the known sequences indicates that plants have two ALDH10 isoenzymes: those known to be GB accumulators have a high-BAL-affinity isoenzyme with Ala or cysteine in this critical position, while non GB accumulators have low-BAL-affinity isoenzymes containing Ile. Therefore, BADH activity appears to restrict GB synthesis in non-GB-accumulator plants. PMID:22345508

  16. Synthesis of bio-based aldehyde from seaweed polysaccharide and its interaction with bovine serum albumin.

    Science.gov (United States)

    Kholiya, Faisal; Chaudhary, Jai Prakash; Vadodariya, Nilesh; Meena, Ramavatar

    2016-10-01

    Here, we demonstrate a successful synthesis of bio-based aldehyde namely dialdehyde-carboxymethylagarose (DCMA) using carboxymethyagarose (CMA). Further reaction parameters (i.e. reaction temperature, pH and periodate concentration) were optimized to achieve maximum aldehyde content and product yield. The synthesis of DCMA was confirmed by employing FTIR, (1)H NMR, XRD, SEM, AFM, TGA, DSC, EA and GPC techniques. To investigate the aldehyde functionality, DCMA was allowed to interact with BSA and obtained results were found to be comparable with that of synthetic aldehyde (Formaldehyde). Further interaction of DCMA with BSA was confirmed by using UV-vis, FTIR, fluorescent spectroscopy, CD and DLS analysis. Results of this study revealed that bio-based aldehyde behaves like formaldehyde. This study adds value to abundant marine biopolymers and opens the new research area for polymer researchers. PMID:27312639

  17. Detailed description of an SSAC at the facility level for mixed oxide fuel fabrication facilities

    International Nuclear Information System (INIS)

    The purpose of this document is to provide a detailed description of a system for the accounting for and control of nuclear material in a mixed oxide fuel fabrication facility which can be used by a facility operator to establish his own system to comply with a national system for nuclear material accounting and control and to facilitate application of IAEA safeguards. The scope of this document is limited to descriptions of the following SSAC elements: (1) Nuclear Material Measurements; (2) Measurement Quality; (3) Records and Reports; (4) Physical Inventory Taking; (5) Material Balance Closing

  18. Coenzyme Q10 in human blood: Native levels and determinants of oxidation during processing and storage

    OpenAIRE

    Franke, Adrian A.; Morrison, Cynthia M.; Bakke, Jesse L.; Custer, Laurie J.; Li, Xingnan; Cooney, Robert V.

    2010-01-01

    Coenzyme Q10 (Q10) is present in the circulation mainly in its reduced form (ubiquinol-10; UL10), but oxidizes quickly ex vivo to ubiquinone-10 (UN10). Therefore, native UL10:UN10 ratios, used as markers of redox status and disease risk, are difficult to measure. We established an RP-(U)HPLC method with coulometric detection to measure natively circulating UL10 and UN10 concentrations by adding a ubiquinol/ubiquinone mixture as an internal standard immediately after plasma preparation. This a...

  19. DNA-Templated Introduction of an Aldehyde Handle in Proteins

    DEFF Research Database (Denmark)

    Kodal, Anne Louise Bank; Rosen, Christian Bech; Mortensen, Michael Rosholm;

    2016-01-01

    Many medical and biotechnological applications rely on labeling of proteins, but one key challenge is the production of homogeneous and site-specific conjugates. This can rarely be achieved by mere residue-specific random labeling, but requires genetic engineering. Using site-selective DNA......-templated reductive amination we create DNA-protein conjugates with control over labeling stoichiometry without genetic engineering. A guiding DNA strand with a metal-binding functionality facilitates site-selectivity by directing coupling of a second reactive DNA strand to the vicinity of a protein metal......-binding site. Here, we demonstrate DNA-templated reductive amination for His6-tagged proteins and native metal-binding proteins, including IgG1 antibodies. We also use a cleavable linker between the DNA and the protein to remove the DNA and introduce a single aldehyde to proteins. This functions as a handle...

  20. Monolayer structures of alkyl aldehydes: Odd-membered homologues

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, T.K. [BP Institute, Department of Chemistry, University of Cambridge, Cambridge (United Kingdom); Clarke, S.M., E-mail: stuart@bpi.cam.ac.u [BP Institute, Department of Chemistry, University of Cambridge, Cambridge (United Kingdom); Bhinde, T. [BP Institute, Department of Chemistry, University of Cambridge, Cambridge (United Kingdom); Castro, M.A.; Millan, C. [Instituto Ciencia de los Materiales de Sevilla, Departamento de Quimica Inorganica (CSIC-Universidad de Sevilla) (Spain); Medina, S. [Centro de Investigacion, Tecnologia e Innovacion de la Universidad de Sevilla (CITIUS), Sevilla (Spain)

    2011-03-01

    Crystalline monolayers of three aldehydes with an odd number of carbon atoms in the alkyl chain (C{sub 7}, C{sub 9} and C{sub 11}) at low coverages are observed by a combination of X-ray and neutron diffraction. Analysis of the diffraction data is discussed and possible monolayer crystal structures are proposed; although unique structures could not be ascertained for all molecules. We conclude that the structures are flat on the surface, with the molecules lying in the plane of the layer. The C{sub 11} homologue is determined to have a plane group of either p2, pgb or pgg, and for the C{sub 7} homologue the p2 plane group is preferred.

  1. Reduction of Aldehydes and Ketones with Potassium Borohydride as Reductant

    Institute of Scientific and Technical Information of China (English)

    罗慧谋; 李毅群

    2005-01-01

    A series of aldehydes and ketones were reduced by potassium borohydride in an ionic liquid/water ([bmim]PF6/H2O) biphasic system to afford corresponding alcohol with high purity in excellent yields. The ionic liquid/water biphasic system could promote the chemoselectivity and the substituents such as nitro group and chlorine remained intact. Aromatic ketones were not as active as aromatic aldhydes and cyclic ketones owing to their higher steric hindrance. The ionic liquid could be recycled and reused. This protocol has notable advantages of no need of phase transfer catalyst and organic solvents, mild conditions, simple operation, short reaction time, ease work-up, high yields and recycling of the ionic liquid.

  2. Changes in plasma hydrogen sulfide and nitric oxide levels and their clinical significance in children with Kawasaki disease

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-hui; ZHANG Chao-ying; WU Jian-xin; ZHANG Ting

    2011-01-01

    Background Cardiac involvement is the most common complication of Kawasaki disease (KD); however,the underlying mechanisms are not understood.The present study was designed to investigate changes in plasma hydrogen sulfide (H2S) and nitric oxide (NO) levels in the acute and recovery stages of KD children and to examine their clinical significance.Methods Thirty-five KD patients and 32 healthy children were enrolled in the study.KD patients were divided into two subgroups:a non-cardiac involvement group and a cardiac involvement group.Plasma H2S levels were measured using the sulfur-sensitive electrode method and plasma NO levels and NO synthase activity were determined using the nitrate reductase method both before and after intravenous immune globulin (IVIG) therapy.Results Plasma H2S levels significantly decreased in KD patients during the acute phase of the disease and NO levels were significantly increased,compared with the control group (P <0.01).After treatment with IVIG,both plasma H2S and NO levels significantly increased (P <0.01).The plasma levels of H2S were significantly lower in the cardiac involvement group compared with the non-cardiac involvement group (P<0.05).Conclusion H2S and NO may play a role in the pathophysiological process of inflammation during the acute phase of KD.Endogenous H2S may exert protective effects with respect to cardiac complications in KD.

  3. Reduction of blood nitric oxide levels is associated with clinical improvement of the chronic pelvic pain related to endometriosis

    Directory of Open Access Journals (Sweden)

    M.G. Rocha

    2015-04-01

    Full Text Available The objective of this prospective study was to determine the plasma levels of nitric oxide (NO in women with chronic pelvic pain secondary to endometriosis (n=24 and abdominal myofascial pain syndrome (n=16. NO levels were measured in plasma collected before and 1 month after treatment. Pretreatment NO levels (μM were lower in healthy volunteers (47.0±12.7 than in women with myofascial pain (64.2±5.0, P=0.01 or endometriosis (99.5±12.9, P<0.0001. After treatment, plasma NO levels were reduced only in the endometriosis group (99.5±12.9 vs 61.6±5.9, P=0.002. A correlation between reduction of pain intensity and reduction of NO level was observed in the endometriosis group [correlation = 0.67 (95%CI = 0.35 to 0.85, P<0.0001]. Reduction of NO levels was associated with an increase of pain threshold in this group [correlation = -0.53 (-0.78 to -0.14, P<0.0001]. NO levels appeared elevated in women with chronic pelvic pain diagnosed as secondary to endometriosis, and were directly associated with reduction in pain intensity and increase in pain threshold after treatment. Further studies are needed to investigate the role of NO in the pathophysiology of pain in women with endometriosis and its eventual association with central sensitization.

  4. Protocatechuic aldehyde inhibits migration and proliferation of vascular smooth muscle cells and intravascular thrombosis

    International Nuclear Information System (INIS)

    Highlights: ► Protocatechuic aldehyde (PCA) inhibits ROS production in VSMCs. ► PCA inhibits proliferation and migration in PDGF-induced VSMCs. ► PCA has anti-platelet effects in ex vivo rat whole blood. ► We report the potential therapeutic role of PCA in atherosclerosis. -- Abstract: The migration and proliferation of vascular smooth muscle cells (VSMCs) and formation of intravascular thrombosis play crucial roles in the development of atherosclerotic lesions. This study examined the effects of protocatechuic aldehyde (PCA), a compound isolated from the aqueous extract of the root of Salvia miltiorrhiza, an herb used in traditional Chinese medicine to treat a variety of vascular diseases, on the migration and proliferation of VSMCs and platelets due to platelet-derived growth factor (PDGF). DNA 5-bromo-2′-deoxy-uridine (BrdU) incorporation and wound-healing assays indicated that PCA significantly attenuated PDGF-induced proliferation and migration of VSMCs at a pharmacologically relevant concentration (100 μM). On a molecular level, we observed down-regulation of the phosphatidylinositol 3-kinase (PI3K)/Akt and the mitogen-activated protein kinase (MAPK) pathways, both of which regulate key enzymes associated with migration and proliferation. We also found that PCA induced S-phase arrest of the VSMC cell cycle and suppressed cyclin D2 expression. In addition, PCA inhibited PDGF-BB-stimulated reactive oxygen species production in VSMCs, indicating that PCA’s antioxidant properties may contribute to its suppression of PDGF-induced migration and proliferation in VSMCs. Finally, PCA exhibited an anti-thrombotic effect related to its inhibition of platelet aggregation, confirmed with an aggregometer. Together, these findings suggest a potential therapeutic role of PCA in the treatment of atherosclerosis and angioplasty-induced vascular restenosis.

  5. Protocatechuic aldehyde inhibits migration and proliferation of vascular smooth muscle cells and intravascular thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Chang Yoon [The Hotchkiss School, Lakeville, CT (United States); Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Ku, Cheol Ryong [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Cho, Yoon Hee, E-mail: wooriminji@gmail.com [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Eun Jig, E-mail: ejlee423@yuhs.ac [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Endocrinology, Northwestern University Feinberg School of Medicine, Chicago, IL (United States)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer Protocatechuic aldehyde (PCA) inhibits ROS production in VSMCs. Black-Right-Pointing-Pointer PCA inhibits proliferation and migration in PDGF-induced VSMCs. Black-Right-Pointing-Pointer PCA has anti-platelet effects in ex vivo rat whole blood. Black-Right-Pointing-Pointer We report the potential therapeutic role of PCA in atherosclerosis. -- Abstract: The migration and proliferation of vascular smooth muscle cells (VSMCs) and formation of intravascular thrombosis play crucial roles in the development of atherosclerotic lesions. This study examined the effects of protocatechuic aldehyde (PCA), a compound isolated from the aqueous extract of the root of Salvia miltiorrhiza, an herb used in traditional Chinese medicine to treat a variety of vascular diseases, on the migration and proliferation of VSMCs and platelets due to platelet-derived growth factor (PDGF). DNA 5-bromo-2 Prime -deoxy-uridine (BrdU) incorporation and wound-healing assays indicated that PCA significantly attenuated PDGF-induced proliferation and migration of VSMCs at a pharmacologically relevant concentration (100 {mu}M). On a molecular level, we observed down-regulation of the phosphatidylinositol 3-kinase (PI3K)/Akt and the mitogen-activated protein kinase (MAPK) pathways, both of which regulate key enzymes associated with migration and proliferation. We also found that PCA induced S-phase arrest of the VSMC cell cycle and suppressed cyclin D2 expression. In addition, PCA inhibited PDGF-BB-stimulated reactive oxygen species production in VSMCs, indicating that PCA's antioxidant properties may contribute to its suppression of PDGF-induced migration and proliferation in VSMCs. Finally, PCA exhibited an anti-thrombotic effect related to its inhibition of platelet aggregation, confirmed with an aggregometer. Together, these findings suggest a potential therapeutic role of PCA in the treatment of atherosclerosis and angioplasty-induced vascular restenosis.

  6. Relation of middle molecules levels and oxidative stress to erythropoietin requirements in high-flux versus low-flux hemodialysis

    Directory of Open Access Journals (Sweden)

    Hala S El-Wakil

    2013-01-01

    Full Text Available The objective of this study is to investigate the serum beta-2-microglobulin (B2MG and advanced oxidation protein products (AOPP as middle molecule uremic toxins and protein carbonyl (PCO as oxidative stress marker in uremic patients undergoing high-flux versus low-flux hemodialysis (HD and to correlate their levels to the erythropoietin requirements for those patients. Twenty patients on chronic low-flux HD were recruited in the study. At the start of the study, all patients underwent high-flux HD for eight weeks, followed by low-flux HD for two weeks as a washout period. The patients were then subjected to another eight weeks of low-flux HD. Blood samples were obtained at the beginning and at the end of the high-flux period and the low-flux period. The mean erythropoietin dose for patients using high-flux HD was significantly lower than that for low-flux HD (P = 0.0062. Post-high flux, the B2MG and PCO levels were significantly lower than the pre-high-flux levels (P = 0.026 and 0.0005, respectively, but no significant change was observed in AOPP (P = 0.68. Post-low flux, the B2MG, AOPP and PCO were significantly higher than the pre-low-flux levels (P = 0.0002, 0.021 and <0.0001, respectively. Post-low flux, the B2MG and PCO were significantly higher than the post-high-flux levels (P <0.0001, but no significant difference was observed in AOPP (P = 0.11. High-flux HD results in reduction of some of the middle molecule toxins and PCO levels better than low-flux HD, and is associated with a better response to erythropoietin.

  7. Pharmacological activities of cilantro's aliphatic aldehydes against Leishmania donovani.

    Science.gov (United States)

    Donega, Mateus A; Mello, Simone C; Moraes, Rita M; Jain, Surendra K; Tekwani, Babu L; Cantrell, Charles L

    2014-12-01

    Leishmaniasis is a chronic infectious disease caused by different Leishmania species. Global occurrences of this disease are primarily limited to tropical and subtropical regions. Treatments are available; however, patients complain of side effects. Different species of plants have been screened as a potential source of new drugs against leishmaniasis. In this study, we investigated the antileishmanial activity of cilantro (Coriandrum sativum) essential oil and its main components: (E)-2-undecenal, (E)-2-decenal, (E)-2-dodecenal, decanal, dodecanal, and tetradecanal. The essential oil of C. sativum leaves inhibits growth of Leishmani donovani promastigotes in culture with an IC50 of 26.58 ± 6.11 µg/mL. The aliphatic aldehydes (E)-2-decenal (7.85 ± 0.28 µg/mL), (E)-2-undecenal (2.81 ± 0.21 µg/mL), and (E)-2-dodecenal (4.35 ± 0.15 µg/mL), all isolated from C. sativum essential oil, are effective inhibitors of in vitro cultures of L. donovani promastigotes. Aldehydes (E)-2-decenal, (E)-2-undecenal, and (E)-2-dodecenal were also evaluated against axenic amastigotes and IC50 values were determined to be 2.47 ± 0.25 µg/mL, 1.25 ± 0.11 µg/mL, and 4.78 ± 1.12 µg/mL, respectively. (E)-2-Undecenal and (E)-2-dodecenal demonstrated IC50 values of 5.65 ± 0.19 µg/mL and 9.60 ± 0.89 µg/mL, respectively, against macrophage amastigotes. These cilantro compounds showed no cytotoxicity against THP-1 macrophages. PMID:25340465

  8. Quantification of Carnosine-Aldehyde Adducts in Human Urine.

    Science.gov (United States)

    da Silva Bispo, Vanderson; Di Mascio, Paolo; Medeiros, Marisa

    2014-10-01

    Lipid peroxidation generates several reactive carbonyl species, including 4-hydroxy-2-nonenal (HNE), acrolein (ACR), 4-hydroxy-2-hexenal (HHE) and malondialdehyde. One major pathwayof aldehydes detoxification is through conjugation with glutathione catalyzed by glutathione-S-transferases or, alternatively, by conjugation with endogenous histidine containing dipeptides, such as carnosine (CAR). In this study, on-line reverse-phase high-performance liquid chromatography (HPLC) separation with tandem mass spectrometry detection was utilized for the accurate quantification of CAR- ACR, CAR-HHE and CAR-HNE adducts in human urinary samples from non-smokers young adults. Standard adducts were prepared and isolated by HPLC. The results showed the presence of a new product from the reaction of CAR with ACR. This new adduct was completely characterized by HPLC/MS-MSn, 1H RMN, COSY and HSQC. The new HPLC/MS/MS methodology employing stable isotope-labeled internal standards (CAR-HHEd5 and CAR-HNEd11) was developed for adducts quantification. This methodology permits quantification of 10pmol CAR-HHE and 1pmol of CAR-ACR and CAR-HNE. Accurate determinations in human urine sample were performed and showed 4.65±1.71 to CAR-ACR, 5.13±1.76 to CAR-HHE and 5.99±3.19nmol/mg creatinine to CAR-HNE. Our results indicate that carnosine pathways can be an important detoxification route of a, ß -unsaturated aldehydes. Moreover, carnosine adducts may be useful as redox stress indicator. PMID:26461323

  9. Serum levels of soluble Fas, nitric oxide and cytokines in acute decompensated cirrhotic patients

    Institute of Scientific and Technical Information of China (English)

    Christoph Elsing; Sabine Harenberg; Wolfgang Stremmel; Thomas Herrmann

    2007-01-01

    AIM: To evaluate plasma levels of nitrite/nitrate (NOx),soluble Fas (sFas) antigen, tumor necrosis factor alpha(TNF-α) and interleukin-6 (TL-6) in patients with compensated and acute decompensated cirrhosis and to evaluate mediators causing acute decompensation in liver cirrhosis.METHODS: This prospective study was conducted in the medical intensive care unit of an academic tertiary center. Fifty-five patients with acute decompensation (gastrointestinal hemorrhage, encephalopathy, hydropic decompensation) and twenty-five patients with compensated liver cirrhosis were included. Blood samples were taken for analyses of sfas, Nox, TL-6, TNF-α. Liver enzymes and kidney functions were also tested.RESULTS: In patients with acute decompensation, plasma sfas levels were higher than in non-decompensated patients (15305±4646 vs 12458 ± 4322 pg/mL, P <0.05). This was also true for the subgroup of patients with alcoholic liver cirrhosis (P < 0.05). The other mediators were not different and none of the parameters predicted survival, except for ALT (alanine-aminotransferase). In patients with portal-hypertension-induced acute hemorrhage, NOx levels were significantly lower than in patients with other forms of decompensation (70.8 ±48.3 vs 112.9 ± 74.9 pg/mL, P < 0.05). When NOx levels were normalized to creatinine levels, the difference disappeared. IL-6, TNF-α and sfas were not different between bleeders and non-bleeders. In decompensated patients sfas, IL-6 and NOx levels correlated positively with creatinine levels, while IL-6 levels were dependent on Child class.CONCLUSION: In acute decompensated cirrhotic patients sFas is increased, suggesting a role of apoptosis in this process and patients with acute bleeding have lower NOx levels. However, in this acute complex clinical situation, kidney function seems to have a predominant influence on mediator levels.

  10. Inhibition of human alcohol and aldehyde dehydrogenases by aspirin and salicylate: assessment of the effects on first-pass metabolism of ethanol.

    Science.gov (United States)

    Lee, Shou-Lun; Lee, Yung-Pin; Wu, Min-Li; Chi, Yu-Chou; Liu, Chiu-Ming; Lai, Ching-Long; Yin, Shih-Jiun

    2015-05-01

    Previous studies have reported that aspirin significantly reduced the first-pass metabolism (FPM) of ethanol in humans thereby increasing adverse effects of alcohol. The underlying causes, however, remain poorly understood. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), principal enzymes responsible for metabolism of ethanol, are complex enzyme families that exhibit functional polymorphisms among ethnic groups and distinct tissue distributions. We investigated the inhibition profiles by aspirin and its major metabolite salicylate of ethanol oxidation by recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and acetaldehyde oxidation by ALDH1A1 and ALDH2, at pH 7.5 and 0.5 mM NAD(+). Competitive inhibition pattern was found to be a predominant type among the ADHs and ALDHs studied, although noncompetitive and uncompetitive inhibitions were also detected in a few cases. The inhibition constants of salicylate for the ADHs and ALDHs were considerably lower than that of aspirin with the exception of ADH1A that can be ascribed to a substitution of Ala-93 at the bottom of substrate pocket as revealed by molecular docking experiments. Kinetic inhibition equation-based simulations show at higher therapeutic levels of blood plasma salicylate (1.5 mM) that the decrease of activities at 2-10 mM ethanol for ADH1A/ADH2 and ADH1B2/ADH1B3 are predicted to be 75-86% and 31-52%, respectively, and that the activity decline for ALDH1A1 and ALDH2 at 10-50 μM acetaldehyde to be 62-73%. Our findings suggest that salicylate may substantially inhibit hepatic FPM of alcohol at both the ADH and ALDH steps when concurrent intaking aspirin.

  11. Inhibition of human alcohol and aldehyde dehydrogenases by aspirin and salicylate: assessment of the effects on first-pass metabolism of ethanol.

    Science.gov (United States)

    Lee, Shou-Lun; Lee, Yung-Pin; Wu, Min-Li; Chi, Yu-Chou; Liu, Chiu-Ming; Lai, Ching-Long; Yin, Shih-Jiun

    2015-05-01

    Previous studies have reported that aspirin significantly reduced the first-pass metabolism (FPM) of ethanol in humans thereby increasing adverse effects of alcohol. The underlying causes, however, remain poorly understood. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), principal enzymes responsible for metabolism of ethanol, are complex enzyme families that exhibit functional polymorphisms among ethnic groups and distinct tissue distributions. We investigated the inhibition profiles by aspirin and its major metabolite salicylate of ethanol oxidation by recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and acetaldehyde oxidation by ALDH1A1 and ALDH2, at pH 7.5 and 0.5 mM NAD(+). Competitive inhibition pattern was found to be a predominant type among the ADHs and ALDHs studied, although noncompetitive and uncompetitive inhibitions were also detected in a few cases. The inhibition constants of salicylate for the ADHs and ALDHs were considerably lower than that of aspirin with the exception of ADH1A that can be ascribed to a substitution of Ala-93 at the bottom of substrate pocket as revealed by molecular docking experiments. Kinetic inhibition equation-based simulations show at higher therapeutic levels of blood plasma salicylate (1.5 mM) that the decrease of activities at 2-10 mM ethanol for ADH1A/ADH2 and ADH1B2/ADH1B3 are predicted to be 75-86% and 31-52%, respectively, and that the activity decline for ALDH1A1 and ALDH2 at 10-50 μM acetaldehyde to be 62-73%. Our findings suggest that salicylate may substantially inhibit hepatic FPM of alcohol at both the ADH and ALDH steps when concurrent intaking aspirin. PMID:25772736

  12. High levels of γ-H2AX foci and cell membrane oxidation in adolescents with type 1 diabetes

    Energy Technology Data Exchange (ETDEWEB)

    Giovannini, Caterina [Unità di Genetica, Dipartimento di Biologia, Pisa University, Pisa (Italy); Piaggi, Simona [Sezione di Patologia Sperimentale, Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, Pisa University, Pisa (Italy); Federico, Giovanni [Unità di Endocrinologia Pediatrica e Diabete, Dipartimento di Medicina Clinica e Sperimentale Pisa University, Pisa (Italy); Scarpato, Roberto, E-mail: roberto.scarpato@unipi.it [Unità di Genetica, Dipartimento di Biologia, Pisa University, Pisa (Italy)

    2014-12-15

    Highlights: • We aimed to detect signs of very early damage in peripheral cells of T1DM adolescents. • T1DM patients had high levels of oxidized cells and reduced expression of iNOS and NO. • Highly mutagenic lesions were markedly increased in the diabetic group, mainly in females. • The observed damage might increase the risk of cancer in the patients later in life. - Abstract: Oxidative stress caused by an excess of free radicals is implicated in the pathogenesis and development of type 1 diabetes mellitus (T1DM) and, in turn, it can lead to genome damage, especially in the form of DNA double-strand break (DSB). The DNA DSB is a potentially carcinogenic lesion for human cells. Thus, we aimed to evaluate whether the level of oxidative stress was increased in peripheral blood lymphocytes of a group of affected adolescents. In 35 T1DM adolescents and 19 healthy controls we assessed: (1) spontaneous and H{sub 2}O{sub 2}-induced oxidation of cell membrane using a fluorescence lipid probe; (2) spontaneous and LPS-induced expression of iNOS protein and indirect NO determination via cytofluorimetric analysis of O{sub 2}{sup −}; (3) immunofluorescent detection of the basal level of histone H2AX phosphorylation (γ-H2AX foci), a well-validated marker of DNA DSB. In T1DM, the frequencies of oxidized cells, both spontaneous and H{sub 2}O{sub 2}-induced (47.13 ± 0.02) were significantly higher than in controls (35.90 ± 0.03). Patients showed, in general, both a reduced iNOS expression and production of NO. Furthermore, the level of spontaneous nuclear damage, quantified as γ-H2AX foci, was markedly increased in T1DM adolescents (6.15 ± 1.08% of γ-H2AX{sup +} cells; 8.72 ± 2.14 γ-H2AXF/n; 9.26 ± 2.37 γ-H2AXF/np), especially in females. In the present study, we confirmed the role that oxidative stress plays in the disease damaging lipids of cell membrane and, most importantly, causing genomic damage in circulating white blood cells of affected adolescents

  13. Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate

    Science.gov (United States)

    Bucy, Harrison

    Microalgae is currently receiving strong consideration as a potential biofuel feedstock to help meet the advanced biofuels mandate of the 2007 Energy Independence and Security Act because of its theoretically high yield (gallons/acre/year) in comparison to current terrestrial feedstocks. Additionally, microalgae also do not compete with food and can be cultivated with wastewater on non-arable land. Microalgae lipids can be converted into a variety of biofuels including fatty acid methyl esters (e.g. FAME biodiesel), renewable diesel, renewable gasoline, or jet fuel. For microalgae derived FAME, the fuel properties will be directly related to the fatty acid composition of the lipids produced by the given microalgae strain. Several microalgae species under consideration for wide scale cultivation, such as Nannochloropsis, produce lipids with fatty acid compositions containing substantially higher quantities of long chainpolyunsaturated fatty acids (LC-PUFA) in comparison to terrestrial feedstocks. It is expected that increased levels of LC-PUFA will be problematic in terms of meeting all of the current ASTM specifications for biodiesel. For example, it is known that oxidative stability and cetane number decrease with increasing levels of LC-PUFA. However, these same LC-PUFA fatty acids, such as eicosapentaenoic acid (EPA: C20:5) and docosahexaenoic acid (DHA: C22:6) are known to have high nutritional value thereby making separation of these compounds economically attractive. Given the uncertainty in the future value of these LC-PUFA compounds and the economic viability of the separation process, the goal of this study was to examine the oxidative stability and ignition quality of algae-based FAME with varying levels of EPA and DHA removal. Oxidative stability tests were conducted at a temperature of 110°C and airflow of 10 L/h using a Metrohm 743 Rancimat with automatic induction period determination following the EN 14112 Method from the ASTM D6751 and EN 14214

  14. Oxidation Stability of Pig Liver Pâté with Increasing Levels of Natural Antioxidants (Grape and Tea

    Directory of Open Access Journals (Sweden)

    Mirian Pateiro

    2015-01-01

    Full Text Available The present study investigated the effect of the addition of increasing levels of the natural antioxidants tea (TEA and grape seed extracts (GRA on the physiochemical and oxidative stability of refrigerated stored pig pâtés. In addition, a synthetic antioxidant and a control batch were used, thus a total of eight batches of liver pâté were prepared: CON, BHT, TEA (TEA50, TEA200 and TEA1000 and GRA (GRA50, GRA200 and GRA1000. Pâté samples were analyzed following 0, 4, 8 and 24 weeks of storage. Color parameters were affected by storage period and level of antioxidant extract. Samples with TEA200 and GRA1000 levels of extracts showed lower total color difference between 0 and 24 weeks. At the end of storage period, the lower TBARs values were obtained in samples with the highest concentration on natural extract. Overall, the evolution of volatile compounds showed an increase in those ones that arise from the lipid oxidation and samples with TEA1000 extract showed the lowest values.

  15. Air pollution in relation to homocysteine serum level and nitric oxide indicators among traffic policemen in Egypt

    Directory of Open Access Journals (Sweden)

    Mansour N

    2011-01-01

    Full Text Available Background: Environmental pollutants are known to be harmful to health. Traffic policemen are placed at particular risk due to nature of their job. The present study examined the effect of air pollution on vascular inflammatory reactions in traffic policemen of Egypt.Methods: Twenty eight policemen who has worked in Shubra El-Khaima and a matched control from Ashmoon, El-Menoufia (n=20 were recruited. Total homocysteine (tHcy and nitric acid indicators (nitrite and nitrate in serum was determined. Each participant was subjected to personal, occupational and medical history, and clinical examination. Particulate matter (PM2.5, sulphur dioxide (SO2 and nitric oxide (NO2 was recorded at various sites.Results: Significant increase in Hcy plasma level was found in the exposed group compared to control. This elevation in tHcy is associated with significant reduction in nitrite and nitrate serum levels. Conclusion: In traffic policemen, exposure to air pollution was associated with increase in tHcy plasma level and reduction in nitric oxide indicators. This raise the attention to the importance of periodic medical assessment of policemen beside the control measures of air pollution.

  16. Glu504Lys Single Nucleotide Polymorphism of Aldehyde Dehydrogenase 2 Gene and the Risk of Human Diseases

    Directory of Open Access Journals (Sweden)

    Yan Zhao

    2015-01-01

    Full Text Available Aldehyde dehydrogenase (ALDH 2 is a mitochondrial enzyme that is known for its important role in oxidation and detoxification of ethanol metabolite acetaldehyde. ALDH2 also metabolizes other reactive aldehydes such as 4-hydroxy-2-nonenal and acrolein. The Glu504Lys single nucleotide polymorphism (SNP of ALDH2 gene, which is found in approximately 40% of the East Asian populations, causes defect in the enzyme activity of ALDH2, leading to alterations in acetaldehyde metabolism and alcohol-induced “flushing” syndrome. Evidence suggests that ALDH2 Glu504Lys SNP is a potential candidate genetic risk factor for a variety of chronic diseases such as cardiovascular disease, cancer, and late-onset Alzheimer’s disease. In addition, the association between ALDH2 Glu504Lys SNP and the development of these chronic diseases appears to be affected by the interaction between the SNP and lifestyle factors such as alcohol consumption as well as by the presence of other genetic variations.

  17. GENDER DIFFERENCES IN BRAIN SUSCEPTIBILITY TO OXIDATIVE STRESS ARE MEDIATED BY LEVELS OF PARAOXONASE-2 (PON2) EXPRESSION

    OpenAIRE

    Giordano, G.; Tait, L.; Furlong, C E; Cole, T B; Kavanagh, T J; Costa, L.G.

    2013-01-01

    Paraoxonase 2 (PON2), a member of a gene family that also includes PON1 and PON3, is expressed in most tissues, including the brain. In mouse brain, PON2 levels are highest in dopaminergic areas (e.g. striatum), and are higher in astrocytes than in neurons. PON2 is primarily located in mitochondria and exerts a potent antioxidant effect, protecting mouse CNS cells against oxidative stress. The aim of this study was to characterize PON2 expression and functions in the brains of male and female...

  18. [Effects of panthenol and carnitine on aldehyde metabolic enzymes in rats with tetrachloromethane-induced liver injury].

    Science.gov (United States)

    Satanovskaia, V I; Pron'ko, P S; Gaĭshmanova, A V; Miskevich, D A

    2009-01-01

    Tetrachloromethane (2 g/kg, intragastric) produced a decrease in the activity of NAD- and NADH- dependent aldehyde dehydrogenases with high Km for aldehydes in rat liver. Panthenol and L-carnitine administered separately normalized the activity of aldehyde dehydrogenases, while a combination of the drugs did not produce any significant effect. PMID:19441727

  19. Transcriptome analysis of Zymomonas mobilis ZM4 reveals mechanisms of tolerance and detoxification of phenolic aldehyde inhibitors from lignocellulose pretreatment

    OpenAIRE

    Yi, Xia; Gu, Hanqi; Gao, Qiuqiang; Liu, Z. Lewis; Bao, Jie

    2015-01-01

    Background Phenolic aldehydes generated from lignocellulose pretreatment exhibited severe toxic inhibitions on microbial growth and fermentation. Numerous tolerance studies against furfural, 5-hydroxymethyl-2-furaldehyde (HMF), acetate, and ethanol were reported, but studies on inhibition of phenolic aldehyde inhibitors are rare. For ethanologenic strains, Zymomonas mobilis ZM4 is high in ethanol productivity and genetic manipulation feasibility, but sensitive to phenolic aldehyde inhibitors....

  20. Trace Level Determination of Mesityl Oxide and Diacetone Alcohol in Atazanavir Sulfate Drug Substance by a Gas Chromatography Method.

    Science.gov (United States)

    Raju, K V S N; Pavan Kumar, K S R; Siva Krishna, N; Madhava Reddy, P; Sreenivas, N; Kumar Sharma, Hemant; Himabindu, G; Annapurna, N

    2016-01-01

    A capillary gas chromatography method with a short run time, using a flame ionization detector, has been developed for the quantitative determination of trace level analysis of mesityl oxide and diacetone alcohol in the atazanavir sulfate drug substance. The chromatographic method was achieved on a fused silica capillary column coated with 5% diphenyl and 95% dimethyl polysiloxane stationary phase (Rtx-5, 30 m x 0.53 mm x 5.0 µm). The run time was 20 min employing programmed temperature with a split mode (1:5) and was validated for specificity, sensitivity, precision, linearity, and accuracy. The detection and quantitation limits obtained for mesityl oxide and diacetone alcohol were 5 µg/g and 10 µg/g, respectively, for both of the analytes. The method was found to be linear in the range between 10 µg/g and 150 µg/g with a correlation coefficient greater than 0.999, and the average recoveries obtained in atazanavir sulfate were between 102.0% and 103.7%, respectively, for mesityl oxide and diacetone alcohol. The developed method was found to be robust and rugged. The detailed experimental results are discussed in this research paper. PMID:27222607

  1. Hormone replacement therapy increases levels of antibodies against heat shock protein 65 and certain species of oxidized low density lipoprotein

    Directory of Open Access Journals (Sweden)

    Uint L.

    2003-01-01

    Full Text Available Hormone replacement therapy (HRT reduces cardiovascular risks, although the initiation of therapy may be associated with transient adverse ischemic and thrombotic events. Antibodies against heat shock protein (Hsp and oxidized low density lipoprotein (LDL have been found in atherosclerotic lesions and plasma of patients with coronary artery disease and may play an important role in the pathogenesis of atherosclerosis. The aim of the present study was to assess the effects of HRT on the immune response by measuring plasma levels of antibodies against Hsp 65 and LDL with a low and high degree of copper-mediated oxidative modification of 20 postmenopausal women before and 90 days after receiving orally 0.625 mg equine conjugate estrogen plus 2.5 mg medroxyprogesterone acetate per day. HRT significantly increased antibodies against Hsp 65 (0.316 ± 0.03 vs 0.558 ± 0.11 and against LDL with a low degree of oxidative modification (0.100 ± 0.01 vs 0.217 ± 0.02 (P<0.05 and P<0.001, respectively, ANOVA. The hormone-mediated immune response may trigger an inflammatory response within the vessel wall and potentially increase plaque burden. Whether or not this immune response is temporary or sustained and deleterious requires further investigation.

  2. Selective Oxidation of Alcohols Using Photoactive VO@g‑C3N4

    Data.gov (United States)

    U.S. Environmental Protection Agency — A photoactive VO@g-C3N4 catalyst has been developed for the selective oxidation of alcohols to the corresponding aldehydes and ketones. The visible light mediated...

  3. THE EFFECT OF USING VITAMIN E ON MUSCLE DAMAGE, OXIDANT AND ANTIOXIDANT LEVELS OF RUNNERS PERFORMING ENDURANCE TRAINING

    Directory of Open Access Journals (Sweden)

    Serdar BÜYÜKİPEKÇİ

    2012-12-01

    Full Text Available This study was made to research the effect of vitamin E on muscle damage, oxidant and antioxidant levels of runners. 28 students participated in the study as the experiment group at the age of 20,75±1,84 (n=16 and the control group (n=12 at the age of 20,42±1,78 who are physically active, have the similar physical features and education at Erciyes University. In this study, the same exercises were performed on both groups three times a week for thirty days. 400 IU (268 mg vitamin E was given to the athletes in experiment group in every day for 30 days. Nothing was given to the control group. The body weights and the percentage of body fat were measured at the pre and post one month exercise. Total antioxidant capacity, malondialdehyde, creatine kinase and lactate dehydrogenase were measured by making biochemical analyses. While any significant difference on pre-exercise CK and LDH levels, pre and post exercise TAC and MDA levels of experiment and control groups was not found, there was a significant difference on post exercise CK and LDH levels as a result of the intergroup comparison. As for the intragroup comparison, there was a significant increase on post exercise MDA level of both experiment and control group. This result was thought that the antioxidant capacity remains incapable; despite usage of vitamin E counter to oxidative stress increasing connectedly exercise. The reason of this inability in the antioxidant defense system is thought that this is because of the amount of daily vitamin E.

  4. Fe-Catalyzed Oxidative Cleavage of Unsaturated Fatty Acids

    OpenAIRE

    Spannring, P.

    2013-01-01

    The oxidative cleavage of unsaturated fatty acids into aldehydes or carboxylic acids gives access to valuable products. The products can be used as chemical building blocks, as emulsifiers or in the paint or polymer industry. Ozonolysis is applied industrially to cleave the fatty acid oleic acid into the aldehydes nonanal and 9-oxo-nonanoic acid or into pelargonic and azelaic acid. Considerable hazards, including explosion risks, are associated with the use of ozone, and alternative processes...

  5. Covalent Immobilization of Bacillus licheniformis γ-Glutamyl Transpeptidase on Aldehyde-Functionalized Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Meng-Chun Chi

    2013-02-01

    Full Text Available This work presents the synthesis and use of surface-modified iron oxide nanoparticles for the covalent immobilization of Bacillus licheniformis γ-glutamyl transpeptidase (BlGGT. Magnetic nanoparticles were prepared by an alkaline solution of divalent and trivalent iron ions, and they were subsequently treated with 3-aminopropyltriethoxysilane (APES to obtain the aminosilane-coated nanoparticles. The functional group on the particle surface and the amino group of BlGGT was then cross-linked using glutaraldehyde as the coupling reagent. The loading capacity of the prepared nanoparticles for BlGGT was 34.2 mg/g support, corresponding to 52.4% recovery of the initial activity. Monographs of transmission electron microscopy revealed that the synthesized nanoparticles had a mean diameter of 15.1 ± 3.7 nm, and the covalent cross-linking of the enzyme did not significantly change their particle size. Fourier transform infrared spectroscopy confirmed the immobilization of BlGGT on the magnetic nanoparticles. The chemical and kinetic behaviors of immobilized BlGGT are mostly consistent with those of the free enzyme. The immobilized enzyme could be recycled ten times with 36.2% retention of the initial activity and had a comparable stability respective to free enzyme during the storage period of 30 days. Collectively, the straightforward synthesis of aldehyde-functionalized nanoparticles and the efficiency of enzyme immobilization offer wide perspectives for the practical use of surface-bound BlGGT.

  6. Effect of aspartame on oxidative stress and monoamine neurotransmitter levels in lipopolysaccharide-treated mice.

    Science.gov (United States)

    Abdel-Salam, Omar M E; Salem, Neveen A; Hussein, Jihan Seid

    2012-04-01

    This study aimed at investigating the effect of the sweetener aspartame on oxidative stress and brain monoamines in normal circumstances and after intraperitoneal (i.p.) administration of lipopolysaccharide (LPS; 100 μg/kg) in mice. Aspartame (0.625-45 mg/kg) was given via subcutaneous route at the time of endotoxin administration. Mice were euthanized 4 h later. Reduced glutathione (GSH), lipid peroxidation (thiobarbituric acid-reactive substances; TBARS), and nitrite concentrations were measured in brain and liver. Tumor necrosis factor-alpha (TNF-α) and glucose were determined in brain. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were measured in liver. The administration of only aspartame (22.5 and 45 mg/kg) increased brain TBARS by 17.7-32.8%, decreased GSH by 25.6-31.6%, and increased TNF-α by 16.7-44%. Aspartame caused dose-dependent inhibition of brain serotonin, noradrenaline, and dopamine. Aspartame did not alter liver TBARS, nitrite, GSH, AST, ALT, or ALP. The administration of LPS increased nitrite in brain and liver by 26.8 and 37.1%, respectively; decreased GSH in brain and liver by 21.6 and 31.1%, respectively; increased brain TNF-α by 340.4%, and glucose by 39.9%, and caused marked increase in brain monoamines. LPS increased AST, ALT, and ALP in liver tissue by 84.4, 173.7, and 258.9%, respectively. Aspartame given to LPS-treated mice at 11.25 and 22.5 mg/kg increased brain TBARS by 15.5-16.9%, nitrite by 12.6-20.1%, and mitigated the increase in monoamines. Aspartame did not alter liver TBARS, nitrite, GSH, ALT, AST, or ALP. Thus, the administration of aspartame alone or in the presence of mild systemic inflammatory response increases oxidative stress and inflammation in the brain, but not in the liver.

  7. α,β-Unsaturated aldehyde of hyaluronan--Synthesis, analysis and applications.

    Science.gov (United States)

    Buffa, Radovan; Šedová, Petra; Basarabová, Ivana; Moravcová, Martina; Wolfová, Lucie; Bobula, Tomáš; Velebný, Vladimír

    2015-12-10

    Hyaluronic acid (HA) modified with an aldehyde group (HA-CHO or HA-aldehyde) has been extensively used for various biomedical applications. The main advantage of the aldehyde moieties is the ability to react with a wide range of amino compounds under physiological conditions. Reactions of aldehydes with primary amines in water are reversible and equilibrium is thoroughly shifted towards starting aldehyde and amine. This work presents an unique modification of HA: α,β-unsaturated aldehyde of HA (4,5-anhydro-6(GlcNAc)-oxo HA or ΔHA-CHO), which allows the primary amines to be attached to HA more effectively in comparison to the saturated HA-CHO. Higher hydrolytic stability is caused by the conjugation of imine with an adjacent --C=C-- double bond. Two strategies for the preparation of unsaturated HA-aldehyde were developed and chemical structures were studied in details. Cross-linked materials prepared from this precursor are biocompatible and suitable for applications in drug delivery and regenerative medicine. PMID:26428127

  8. Quantification of trace level of fluoride content in uranium oxide produced by deconversion of HEX gas by ion chromatography

    International Nuclear Information System (INIS)

    Fluoride content in nuclear fuel is detrimental due to its corrosion behavior with cladding material. It is essential to monitor and control the fluoride concentration in nuclear material at various processing stages. Deconversion of upgraded HEX gas is carried out to produce uranium oxide. The performance of the deconversion process of HEX gas is evaluated for which trace level of fluoride concentration accompanying uranium oxide is considered as a marker. An analytical method has been developed for testing the uranium oxide produced from deconversion process of HEX gas. The method involves sample pretreatment followed by analysis using ion chromatography. The test method was validated for its performance using in house synthetic uranyl fluoride (UO2F2) standard solutions prepared with different level of fluoride content. The results are in agreement with the expected values with the recovery in the range of 80-95%. This method has been successfully implemented for routine analysis of samples at our lab. Since UO2F2 reference material is not available to validate this method, in house UO2F2 standards were prepared from U3O8 prepared from nuclear grade uranyl nitrate solution. UO2F2 standards were prepared by converting U3O8 to UO2F2 by the addition of HF followed by H2O2 at 200°C on a hot plate. The entire yellow colored UO2F2 was dissolved in nano pure water and recrystallised several times to ensure that all free HF is removed. The crystals dried in air oven at 120° for three hours. Samples containing 1000 mg kg-1 fluoride prepared from this UO2F2, and subsequently from this sample containing 5 mg kg-1 to 35 mg kg-1 fluoride samples were prepared and analysed against fluoride CRM and the fluoride concentration obtained was analysed

  9. Correlation between the serum level of advanced oxidation protein products and the cognitive function in patients with obstructive sleep apnea hypopnea syndrome

    Institute of Scientific and Technical Information of China (English)

    杨秀红

    2013-01-01

    Objective To observe the change of the cognitive function and the serum level of advanced oxidation protein products(AOPP) in patients with obstructive sleep apnea hypopnea syndrome(OSAHS),and then to investigate

  10. The plasma level of nitric oxide and the expression of inducible nitric oxidesynthase in human hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Run Xuan Shao; Jiang Bin Wang; Jia He Guo

    2000-01-01

    AIM To study the relationship between nitric oxide (NO), nitric oxide synthase (NOS) and humanhepatocellular carcinoma (HCC).METHODS Plsama NO2-/NO3- was measured by Griess reaction in 122 patients with chronic hepatitis(CH) and compensated liver cirrhosis (LC), among which 62 patients were complicated with HCC(CH = 28, LC = 34), and the rest 60 patients were not (CH = 29, LC = 31). Thirty healthy persons served asnormal controls (NC). There were no prominent differences among the groups in sex, age and the ratio ofCH to LC. The expression of inducible nitric oxide synthase (iNOS) in HCC (n = 40), CH (n = 30) and LC(n = 30) samples obtained from liver biopsy or operation was compared with that in normal liver tissues byusing immunohistochemistry. Ten normal liver tissue samples obtained from liver operation served as normalcontrols. The samples were fixed in formalin and embeded in paraffin. Anti-iNOS antibody (Santacruzcompany) was served as antibody-Ⅰ in immunohistochemical assay of iNOS in tissue.RESULTS Plasma NO2-/NO3- level in normal was 11.5 μmol/L±4.2μmol/L. The plasma level ofNO2 /NO3- in CH (58.6±17.4 μmol/L) and LC (38.7±10.6μmol/L) accompanied with HCC wasnotably higher than in those patients without HCC (CH: 24.8±9.4 μmol/L; LC: 22.3±8.7μmol/L,t=2.901, 2.756, P<0.01). Plasma NO2-/NO3- level in HCC accompanied with CH was significantlyhigher than in those accompanied with LC ( t = 2.216, P<0.05). Positive rate of iNOS in HCC, CH and LCwas 95%, 93% and 57% respectively. iNOS was not expressed in normal liver tissues. The expression level ofiNOS in HCC (χ2=17.4, P<0.001) and CH (χ2=11.64, P<0.025) was much higher than in LC.CONCLUSION Plasma NO2 / NO3- level significantly increased in patients with HCC and theimmunohistochemical staining of iNOS was positive. This suggests that the liver secrets NO in the higherlevel may participate in the carcinogenesis and progression of HCC.

  11. [Level nitric oxide (NO) and growth of roots of etiolated pea seedlings].

    Science.gov (United States)

    Glian'ko, A K; Ishchenko, A A

    2013-01-01

    Data regarding the interrelation of nitric oxide (NO) content in roots of 3-day-old etiolated pea seedlings and their growth under different concentrations of N-containing compounds were obtained. The concentration of exogenous compounds (sodium nitroprusside SNP, KNO3, NaNO2, L-arginine) rendering an inhibiting effect on the growth of roots were established, and the NO content in roots was determined at these concentration. It was shown that the inhibition of growth and highest NO content in the roots was determined with SNP (4 mM) and NaNO2 (2 mM) during 24 h exposition of seedlings. This dependence was not established in combinations with KNO3 (20 mM) and L-arginine (4 mM). We established that a NO scavenger, hemoglobin (4 μM), fully or partially removed the toxic effect of SNP, nitrate, and nitrite on growth. The effect of NO on the growth and the participation of N-containing compounds in generation of NO in roots of pea seedlings is discussed. PMID:25518555

  12. CYP2E1 epigenetic regulation in chronic, low-level toluene exposure: Relationship with oxidative stress and smoking habit

    International Nuclear Information System (INIS)

    Background: CYP2E1 is a versatile phase I drug-metabolizing enzyme responsible for the biotransformation of most volatile organic compounds, including toluene. Human toluene exposure increases CYP2E1 mRNA and modifies its activity in leucocytes; however, epigenetic implications of this interaction have not been investigated. Goal: To determine promoter methylation of CYP2E1 and other genes known to be affected by toluene exposure. Methods: We obtained venous blood from 24 tannery workers exposed to toluene (mean levels: 10.86 +/− 7 mg/m3) and 24 administrative workers (reference group, mean levels 0.21 +/− 0.02 mg/m3) all of them from the city of León, Guanajuato, México. After DNA extraction and bisulfite treatment, we performed PCR-pyrosequencing in order to measure methylation levels at promoter region of 13 genes. Results: In exposed group we found significant correlations between toluene airborne levels and CYP2E1 promoter methylation (r = − .36, p < 0.05), as well as for IL6 promoter methylation levels (r = .44, p < 0.05). Moreover, CYP2E1 promoter methylation levels where higher in toluene-exposed smokers compared to nonsmokers (p = 0.009). We also observed significant correlations for CYP2E1 promoter methylation with GSTP1 and SOD1 promoter methylation levels (r = − .37, p < 0.05 and r = − .34, p < 0.05 respectively). Conclusion: These results highlight the importance of considering CYP2E1 epigenetic modifications, as well as its interactions with other genes, as key factors for unraveling the sub cellular mechanisms of toxicity exerted by oxidative stress, which can initiate disease process in chronic, low-level toluene exposure. People co-exposed to toluene and tobacco smoke are in higher risk due to a possible CYP2E1 repression. - Highlights: • We investigated gene-specific methylation in persons chronically exposed to toluene. • In a previous study, a reduced CYP2E1 activity was observed in these participants. • CYP2E1 promoter

  13. CYP2E1 epigenetic regulation in chronic, low-level toluene exposure: Relationship with oxidative stress and smoking habit

    Energy Technology Data Exchange (ETDEWEB)

    Jiménez-Garza, Octavio, E-mail: ojimenezgarza@ugto.mx [Health Sciences Division, University of Guanajuato Campus León, Blvd. Puente del Milenio 1001, Fracción del Predio San Carlos, C.P. 37670 León, Guanajuato (Mexico); Baccarelli, Andrea A.; Byun, Hyang-Min [Laboratory of Environmental Epigenetics, Department of Environmental Health, Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA 02115 (United States); Márquez-Gamiño, Sergio [Health Sciences Division, University of Guanajuato Campus León, Blvd. Puente del Milenio 1001, Fracción del Predio San Carlos, C.P. 37670 León, Guanajuato (Mexico); Barrón-Vivanco, Briscia Socorro [Environmental Toxicology and Pollution Laboratory, Nayarit Autonomous University, Av. Ciudad de la Cultura s/n, “Amado Nervo”, Tepic, Nayarit C.P. 63155 (Mexico); Albores, Arnulfo [Department of Toxicology, CINVESTAV, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, 07360 Mexico DF (Mexico)

    2015-08-01

    Background: CYP2E1 is a versatile phase I drug-metabolizing enzyme responsible for the biotransformation of most volatile organic compounds, including toluene. Human toluene exposure increases CYP2E1 mRNA and modifies its activity in leucocytes; however, epigenetic implications of this interaction have not been investigated. Goal: To determine promoter methylation of CYP2E1 and other genes known to be affected by toluene exposure. Methods: We obtained venous blood from 24 tannery workers exposed to toluene (mean levels: 10.86 +/− 7 mg/m{sup 3}) and 24 administrative workers (reference group, mean levels 0.21 +/− 0.02 mg/m{sup 3}) all of them from the city of León, Guanajuato, México. After DNA extraction and bisulfite treatment, we performed PCR-pyrosequencing in order to measure methylation levels at promoter region of 13 genes. Results: In exposed group we found significant correlations between toluene airborne levels and CYP2E1 promoter methylation (r = − .36, p < 0.05), as well as for IL6 promoter methylation levels (r = .44, p < 0.05). Moreover, CYP2E1 promoter methylation levels where higher in toluene-exposed smokers compared to nonsmokers (p = 0.009). We also observed significant correlations for CYP2E1 promoter methylation with GSTP1 and SOD1 promoter methylation levels (r = − .37, p < 0.05 and r = − .34, p < 0.05 respectively). Conclusion: These results highlight the importance of considering CYP2E1 epigenetic modifications, as well as its interactions with other genes, as key factors for unraveling the sub cellular mechanisms of toxicity exerted by oxidative stress, which can initiate disease process in chronic, low-level toluene exposure. People co-exposed to toluene and tobacco smoke are in higher risk due to a possible CYP2E1 repression. - Highlights: • We investigated gene-specific methylation in persons chronically exposed to toluene. • In a previous study, a reduced CYP2E1 activity was observed in these participants. • CYP2E1

  14. Estimation of salivary nitric oxide and uric acid levels in oral squamous cell carcinoma and healthy controls

    Directory of Open Access Journals (Sweden)

    Varsha Salian

    2015-01-01

    Full Text Available Background: Oral squamous cell carcinoma (OSCC being the most common head and neck cancer, involves the interplay of several free radicals and antioxidant molecules. The potential role of salivary nitric oxide (NO and uric acid in cancer development needs to be explored as there are a few studies highlighting their association with each other and with oral cancer. Aims: The present study was designed to measure the NO and uric acid levels in the saliva of patients with OSCC as compared with healthy controls and to highlight any possible correlations between them. Materials and Methods: The present study involved 50 subjects, 25 with OSCC (study and 25 healthy individuals (controls. Saliva samples collected from patients were subjected to NO and uric acid analysis by griess method and uricase method, respectively. Statistical Analysis: The results were analyzed using Student′s t-test and Pearson′s Chi-square test. Results: A significant increase in the salivary levels of NO was seen in study subjects as compared to healthy controls. On the contrary, a significant decrease in salivary uric acid level was observed in the study group as compared to healthy controls. In addition, there exists an inverse correlation between NO and uric acid levels in study and control groups. Conclusion: Salivary levels of NO and uric acid may act as key bimolecular markers in the detection of oral cancer, which could be further confirmed by larger sample size and future studies.

  15. Inhibition of neutral sphingomyelinase decreases elevated levels of inducible nitric oxide synthase and apoptotic cell death in ocular hypertensive rats

    International Nuclear Information System (INIS)

    Endoplasmic reticulum (ER) stress and excessive nitric oxide production via induction of inducible nitric oxide synthase (NOS2) have been implicated in the pathogenesis of neuronal retinal cell death in ocular hypertension. Neutral sphingomyelinase (N-SMase)/ceramide pathway can regulate NOS2 expression, hence this study determined the role of selective neutral sphingomyelinase (N-SMase) inhibition on retinal NOS2 levels, ER stress, apoptosis and visual evoked potentials (VEPs) in a rat model of elevated intraocular pressure (EIOP). NOS2 expression and retinal protein nitration were significantly greater in EIOP and significantly decreased with N-SMase inhibition. A significant increase was observed in retinal ER stress markers pPERK, CHOP and GRP78 in EIOP, which were not significantly altered by N-SMase inhibition. Retinal TUNEL staining showed increased apoptosis in all EIOP groups; however N-SMase inhibition significantly decreased the percent of apoptotic cells in EIOP. Caspase-3, -8 and -9 activities were significantly increased in EIOP and returned to baseline levels following N-SMase inhibition. Latencies of all VEP components were significantly prolonged in EIOP and shortened following N-SMase inhibition. Data confirm the role of nitrative injury in EIOP and highlight the protective effect of N-SMase inhibition in EIOP via down-regulation of NOS2 levels and nitrative stress. - Highlights: • Inhibition of N-SMase decreases NOS2 levels in ocular hypertension. • Inhibition of N-SMase decreases protein nitration in ocular hypertension. • Inhibition of N-SMase decreases caspase activation in ocular hypertension. • Inhibition of N-SMase decreases apoptosis in ocular hypertension

  16. Inhibition of neutral sphingomyelinase decreases elevated levels of inducible nitric oxide synthase and apoptotic cell death in ocular hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Aslan, Mutay, E-mail: mutayaslan@akdeniz.edu.tr [Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya (Turkey); Basaranlar, Goksun [Department of Biophysics, Akdeniz University Faculty of Medicine, Antalya (Turkey); Unal, Mustafa [Department of Ophthalmology, Akdeniz University Faculty of Medicine, Antalya (Turkey); Ciftcioglu, Akif [Department of Pathology, Akdeniz University Faculty of Medicine, Antalya (Turkey); Derin, Narin [Department of Biophysics, Akdeniz University Faculty of Medicine, Antalya (Turkey); Mutus, Bulent [Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario (Canada)

    2014-11-01

    Endoplasmic reticulum (ER) stress and excessive nitric oxide production via induction of inducible nitric oxide synthase (NOS2) have been implicated in the pathogenesis of neuronal retinal cell death in ocular hypertension. Neutral sphingomyelinase (N-SMase)/ceramide pathway can regulate NOS2 expression, hence this study determined the role of selective neutral sphingomyelinase (N-SMase) inhibition on retinal NOS2 levels, ER stress, apoptosis and visual evoked potentials (VEPs) in a rat model of elevated intraocular pressure (EIOP). NOS2 expression and retinal protein nitration were significantly greater in EIOP and significantly decreased with N-SMase inhibition. A significant increase was observed in retinal ER stress markers pPERK, CHOP and GRP78 in EIOP, which were not significantly altered by N-SMase inhibition. Retinal TUNEL staining showed increased apoptosis in all EIOP groups; however N-SMase inhibition significantly decreased the percent of apoptotic cells in EIOP. Caspase-3, -8 and -9 activities were significantly increased in EIOP and returned to baseline levels following N-SMase inhibition. Latencies of all VEP components were significantly prolonged in EIOP and shortened following N-SMase inhibition. Data confirm the role of nitrative injury in EIOP and highlight the protective effect of N-SMase inhibition in EIOP via down-regulation of NOS2 levels and nitrative stress. - Highlights: • Inhibition of N-SMase decreases NOS2 levels in ocular hypertension. • Inhibition of N-SMase decreases protein nitration in ocular hypertension. • Inhibition of N-SMase decreases caspase activation in ocular hypertension. • Inhibition of N-SMase decreases apoptosis in ocular hypertension.

  17. Quercetin induces hepatic lipid omega-oxidation and lowers serum lipid levels in mice.

    NARCIS (Netherlands)

    n den Hil, E.F. Hoek-va; Keijer, J.; Bunschoten, A.; Vervoort, J.J.; Stankova, B.; Bekkenkamp, M.; Herreman, L.; Venema, D.; Hollman, P.C.H.; Tvrzicka, E.; Rietjens, I.M.C.M.; Schothorst, E.M. van

    2013-01-01

    Elevated circulating lipid levels are known risk factors for cardiovascular diseases (CVD). In order to examine the effects of quercetin on lipid metabolism, mice received a mild-high-fat diet without (control) or with supplementation of 0.33% (w/w) quercetin for 12 weeks. Gas chromatography and (1)

  18. Assessment of serum homocysteine, endothelin-1, and nitric oxide levels in behçet′s disease

    Directory of Open Access Journals (Sweden)

    Hodeib Abeer

    2010-01-01

    Full Text Available Background: Some prominent features of Behηet′s disease (BD are arterial and venous thromboses as a result of endothelial dysfunction. Hyperhomocysteinemia is responsible for vascular endothelial injury due to an increased frequency of thrombogenesis. Endothelin-1 (ET-1 is a vasoconstrictor whereas nitric oxide (NO is an endothelial vasorelaxing peptide that is responsible for the inhibition of platelet adhesion. Aim: To evaluate serum levels of homocysteine (Hcy and determine whether hyperhomocysteinemia is considered as a contributing risk factor for venous and arterial thromboses of BD, and to correlate serum levels of ET-1 and NO with disease activity. Materials and Methods: We measured serum levels of Hcy, ET-1, and nitrite (NO2 - in 25 patients who fulfilled the criteria of the International Study Group for BD, and compared them to those of 15 healthy control subjects. Levels of Hcy and ET-1 were measured by using enzyme-linked immunosorbent assay (ELISA, whereas serum nitrite (NO2 - levels were measured by using Griess reaction as an indicator for NO production. All the patients were screened for a history of venous thrombosis and subdivided into thrombotic and nonthrombotic subgroups according to their thrombotic history. Patients with BD were divided into two subgroups, active and inactive, according to their clinical and laboratory findings. Results: There were significant increases in serum levels of Hcy, ET-1, and nitrite in BD patients compared to those in controls. There was a significant increase in serum Hcy levels in thrombotic compared to nonthrombotic subgroups. Positive correlations were detected between the serum ET-1 and nitrite levels with disease activity in BD patients. Conclusions: Hyperhomocysteinemia may play some role in the development of venous and arterial thromboses in BD. Increased NO production might have critical biological activities that are relevant to pathological events in the active period of the

  19. Antimony(v) cations for the selective catalytic transformation of aldehydes into symmetric ethers, α,β-unsaturated aldehydes, and 1,3,5-trioxanes.

    Science.gov (United States)

    Arias Ugarte, Renzo; Devarajan, Deepa; Mushinski, Ryan M; Hudnall, Todd W

    2016-07-01

    1-Diphenylphosphinonaphthyl-8-triphenylstibonium triflate ([][OTf]) was prepared in excellent yield by treating 1-lithio-8-diphenylphosphinonaphthalene with dibromotriphenylstiborane followed by halide abstraction with AgOTf. This antimony(v) cation was found to be stable toward oxygen and water, and exhibited exceptional Lewis acidity. The Lewis acidity of [][OTf] was exploited in the catalytic reductive coupling of a variety of aldehydes into symmetric ethers of type in good to excellent yields under mild conditions using Et3SiH as the reductant. Additionally, [][OTf] was found to selectively catalyze the Aldol condensation reaction to afford α-β unsaturated aldehydes () when aldehydes with 2 α-hydrogen atoms were used. Finally, [][OTf] catalyzed the cyclotrimerization of aliphatic and aromatic aldehydes to afford the industrially-useful 1,3,5 trioxanes () in good yields, and with great selectivity. This phosphine-stibonium motif represents one of the first catalytic systems of its kind that is able to catalyze these reactions with aldehydes in a controlled, efficient manner. The mechanism of these processes has been explored both experimentally and theoretically. In all cases the Lewis acidic nature of the antimony(v) cation was found to promote these reactions. PMID:27326797

  20. Transformations of several monoterpenoids in the presence of aldehydes in supercritical solvents

    Science.gov (United States)

    Anikeev, V. I.; Sivcev, V. P.; Il'ina, I. V.; Korchagina, D. V.; Statsenko, O. B.; Volcho, K. P.; Salakhutdinov, N. F.

    2013-03-01

    The reactivity of verbenol epoxide and isopulegol in supercritical solvents in the presence of aromatic aldehydes was studied using a flow type reactor and a heterogeneous catalyst (Al2O3) or no catalyst. The intramolecular transformations or interactions of reagents with the solvent prevailed in all cases; the yield of the products of intermolecular reactions of terpenoids with aldehydes was up to 1%. The aldehydes did not interact with verbenol epoxide but produced a considerable effect on the distribution of its isomerization products.

  1. Exhaled nitric oxide levels and lung function changes of underground coal miners in Newcastle, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.H.; Salter, A.; Thomas, P.; Leigh, J.; Wang, H. [Tulane University, New Orleans, LA (USA). Dept. of Environmental Health Science

    2010-07-01

    The possibility of exhaled nitric oxide (eNO) in combination with lung function as a marker of airway inflammation produced by coal mining exposure was determined presuming that workers exposed to airborne hazards would possess different concentrations of eNO and decreased lung function indices, relative to control subjects recruited from the same area. The effect of smoking was also considered. A study (exposed) group comprising 186 male subjects (aged 19-58 yr) was recruited from Newcastle coal mining companies with 86 male subjects (aged 20-64 yr) from the same area, but working outside of the coal mining location, serving as controls. The parameters examined were eNO, lung function, and variables derived from an interview-administered questionnaire survey. After adjustment for age, body weight, and smoking status, no significant differences between exposed coal mining workers and controls were found for various lung function parameters. However, the exposed group was shown to have significantly lower concentrations of eNO. In the exposed group, forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1 (%) predicted were found to be significantly different between nonsmokers and smokers. The concentrations of eNO were not significantly different between smoking and nonsmokers within the exposed group. Data suggest that exposure to airborne hazards in coal mining is not significantly associated with lung function changes but is correlated with decreased eNO concentrations in exposed workers. While underground work duration was not found to be significantly associated with eNO concentrations in coal mining workers in this study, the potential for using eNO as a monitoring marker still exists and further studies are needed to establish its importance.

  2. Saliva nitric oxide levels in relation to caries experience and oral hygiene

    Directory of Open Access Journals (Sweden)

    Enas H. Mobarak

    2011-10-01

    Full Text Available The aim of the present study was to determine the relationship between nitric oxide (NO concentration/rate in the unstimulated whole saliva (UWS and stimulated whole saliva (SWS with the decay-missing-filled teeth (DMFT and simplified oral hygiene (OHI-s scores. Forty adults were included in the study. Half of the participants (n = 20 had high DMFT-OHI-s compared to the other half. UWS and SWS flow rates, initial and final pHs were also measured. NO concentrations in the UWS and SWS of high and low DMFT-OHI-s groups were determined using modified Griess reaction and NO rates were calculated. The two groups revealed no significant differences in their salivary flow rates and their initial pH. NO concentrations/rates in the UWS and SWS of high and low DMFT-OHI-s groups were not statistically different (p > 0.05. There was no significant correlation between NO concentration or NO rate and other tested variables (DMFT-OHI-s, initial pH and final pH. However, a significant correlation was found between UWS NO rate and UWS flow rate (r = 0.921, p = 0.0001 and SWS NO rate and between SWS flow rate (r = 0.921, p = 0.0001. It could be concluded that neither NO concentration nor NO rate correlates with the dental status. As the exposure to any salivary component (including NO depends not only on its concentration but also on the rate of production of such concentration, it would be of value when determining individuals’ salivary components to consider their rate values rather than their absolute concentrations.

  3. Upregulating of Fas, integrin beta4 and P53 and depressing of PC-PLC activity and ROS level in VEC apoptosis by safrole oxide.

    Science.gov (United States)

    Zhao, Jing; Miao, Junying; Zhao, Baoxiang; Zhang, Shangli

    2005-10-24

    Previously, we found that safrole oxide could trigger vascular endothelial cell (VEC) apoptosis. In this study, to investigate its mechanism to induce apoptosis in VECs, the activities of nitric oxide synthetase and phosphatidylcholine specific phospholipase C, the level of reactive oxygen species and the expressions of Fas, integrin beta4 and P53 were analyzed. The data showed that safrole oxide induced apoptosis by increasing the expressions of Fas, integrin beta4 and P53, and depressing the activity of Ca(2+)-independent phosphatidylcholine-specific phospholipase C and intracellular reactive oxygen species levels in VECs.

  4. Determination of Sulfur Content at PPB Level in Light Oils by Oxidative Microcoulometry

    Institute of Scientific and Technical Information of China (English)

    Yang Defeng; He Pei

    2002-01-01

    A method for determination of sulfur content at ppb level in light oils is proposed. The key technique of the method includes the design of a new type of pyrolysis tube, which is characterized by large capacity and nested structure, and the optimization of operating conditions. The achievable lowest detection limit is 50ng/g. For the samples in which the sulfur content is less than lmg/L, this method features better precision and accuracy, good linearity and quicker test speed.

  5. Decreased hippocampal homoarginine and increased nitric oxide and nitric oxide synthase levels in rats parallel training in a radial arm maze.

    Science.gov (United States)

    Sase, Ajinkya; Nawaratna, Gayan; Hu, Shengdi; Wu, Guoyao; Lubec, Gert

    2016-09-01

    L-homoarginine (hArg) is derived from enzymatic guanidination of lysine. It was demonstrated that hArg is a substrate for nitric oxide (NO) synthesis, blocks lysine transport and inhibits the uptake of arginine into synaptosomes and modulates GABA responses ex vivo. As there is limited information on its physiological roles in the brain, the aim of the study was to show whether hippocampal or frontal lobe (FL) hArg is paralleling training in the radial arm maze (RAM) or NO formation. Hippocampi and FL of male Sprague-Dawley rats were taken from trained or yoked in a RAM. Then hArg and metabolites, NO and NO synthase (NOS) were determined by standard methods. The animals learned the task in the RAM showing significant reduction of working memory errors. hArg showed decreased levels in both brain regions of trained animals as compared to yoked animals. Nitrate plus nitrite (NOx) concentrations and NOS activity were significantly increased in hippocampi, F(1,36) = 170.5; P ≤ 0.0001 and FL, F(1,36) = 74.67; P ≤ 0.0001 of trained animals as compared to yoked animals. Levels of hArg were negatively correlated with NOx in hippocampus (r = -0.6355; P = 0.0483) but not in FL and with lysine in the FL (r = -0.6650; P = 0.0358). NOx levels were positively correlated with NOS in both the hippocampus (r = 0.7474; P = 0.0129) and FL (r = 0.9563; P ≤  0.0001). These novel findings indicate that hArg is linked to NO formation in hippocampus but not in FL and is paralleling spatial memory in the RAM. PMID:27178025

  6. Decreased hippocampal homoarginine and increased nitric oxide and nitric oxide synthase levels in rats parallel training in a radial arm maze.

    Science.gov (United States)

    Sase, Ajinkya; Nawaratna, Gayan; Hu, Shengdi; Wu, Guoyao; Lubec, Gert

    2016-09-01

    L-homoarginine (hArg) is derived from enzymatic guanidination of lysine. It was demonstrated that hArg is a substrate for nitric oxide (NO) synthesis, blocks lysine transport and inhibits the uptake of arginine into synaptosomes and modulates GABA responses ex vivo. As there is limited information on its physiological roles in the brain, the aim of the study was to show whether hippocampal or frontal lobe (FL) hArg is paralleling training in the radial arm maze (RAM) or NO formation. Hippocampi and FL of male Sprague-Dawley rats were taken from trained or yoked in a RAM. Then hArg and metabolites, NO and NO synthase (NOS) were determined by standard methods. The animals learned the task in the RAM showing significant reduction of working memory errors. hArg showed decreased levels in both brain regions of trained animals as compared to yoked animals. Nitrate plus nitrite (NOx) concentrations and NOS activity were significantly increased in hippocampi, F(1,36) = 170.5; P ≤ 0.0001 and FL, F(1,36) = 74.67; P ≤ 0.0001 of trained animals as compared to yoked animals. Levels of hArg were negatively correlated with NOx in hippocampus (r = -0.6355; P = 0.0483) but not in FL and with lysine in the FL (r = -0.6650; P = 0.0358). NOx levels were positively correlated with NOS in both the hippocampus (r = 0.7474; P = 0.0129) and FL (r = 0.9563; P ≤  0.0001). These novel findings indicate that hArg is linked to NO formation in hippocampus but not in FL and is paralleling spatial memory in the RAM.

  7. Endothelial dysfunction in high fructose containing diet fed rats: Increased nitric oxide and decreased endothelin-1 levels in liver tissue

    Directory of Open Access Journals (Sweden)

    Zeki Arı

    2010-09-01

    Full Text Available Objectives: Dietary high fructose consumption which is closely associated with endothelial dysfunction via insulin re-sistance has recently increased in developed countries. Insulin resistance has a promoter effect on many metabolic disorders such as syndrome X, polycystic ovary syndrome, Type 2 diabetes mellitus etc. Our aim in this study is to understand the impact of increased fructose intake on metabolisms of glucose, insulin and endothelial dysfunction by measuring nitric oxide (NO and endothelin-1 (ET-1 levels in hepatic tissue which is crucial in fructose metabolism.Materials and Methods: We designed an animal study to understand increased fructose intake on hepatic endothe-lium. Twenty adult male albino rats were divided into two groups; the study group (group 1, n=10 received isocaloric fructose enriched diet (fructose-fed rats, containing 18.3% protein, 60.3% fructose and 5.2% fat while the control group received purified regular chow (group 2, n=10 for 2 weeks. After feeding period, blood and hepatic tissue samples were collected and glucose, insulin, NO and ET-1 levels were analysed.Results: We found increased fasting glucose and insulin levels and impaired glucose tolerance in fructose fed rats. Higher NO and lower ET–1 levels were also detected in hepatic tissue samples of the group 1.Conclusion: Increased fructose consumption has deleterious effects on glucose tolerance, insulin resistance and may cause to endothelial dysfunction.

  8. Investigations into the organism level effects of the copper-induced oxidative stress response of Lemna gibba

    Energy Technology Data Exchange (ETDEWEB)

    Wall, V.D.; Klaine, S.J. [Clemson Univ., Pendleton, SC (United States)

    1995-12-31

    The use of biochemical endpoints to indicate exposure to environmental toxicants is becoming an accepted technique to determine chemical bio-availability. However, these biochemical endpoints, or biomarkers, have not fulfilled their potential as indicators of sublethal stress when used in this capacity. Difficulties associated with using biochemical endpoints to assess stress arise in differentiating an ``abnormal`` stress response from a physiologically acceptable one and identifying sublethal stress in a biologically and ecologically significant manner. This research examines organism level effects of the copper-induced oxidative-stress response in Lemna gibba. The growth of Lemna gibba was significantly inhibited by aqueous copper concentrations greater than 0.05 ppm during a 10 day exposure. Although effects were dose dependent, the results indicated a conspicuous decrease in growth rates and increase in malformation and chlorosis at 0.5 ppm copper and higher. There were significantly elevated levels of lipid peroxidation products (expressed as thiobarbituric acid reactive species (TBARS)) at 0.1 ppm copper and higher. A decrease in growth rates without an increase in TBARS suggested a diversion of energy towards defensive mechanisms, primarily, superoxide dismutase, peroxidase, catalase and glutathione. These parameters were investigated and analyzed with respect to the organism-level effects (growth rates) of Lemna gibba. The utility and relevance of these sub-cellular parameters as indicators of chemical induced stress at the organism level will be discussed.

  9. Evaluation of Delta-Aminolevulinic Dehydratase Activity, Oxidative Stress Biomarkers, and Vitamin D Levels in Patients with Multiple Sclerosis.

    Science.gov (United States)

    Polachini, Carla Roberta Nunes; Spanevello, Roselia Maria; Zanini, Daniela; Baldissarelli, Jucimara; Pereira, Luciane Belmonte; Schetinger, Maria Rosa Chitolina; da Cruz, Ivana Beatrice Mânica; Assmann, Charles Elias; Bagatini, Margarete Dulce; Morsch, Vera Maria

    2016-02-01

    Multiple sclerosis (MS) is an autoimmune neurological disorder of unknown etiology. Oxidative stress and alterations in vitamin D levels have been implicated in the pathophysiology of MS. The aim of this study was to investigate δ-aminolevulinate dehydratase (δ-ALA-D) activity as well as the levels of vitamin D, lipid peroxidation levels, carbonyl protein content, DNA damage, superoxide dismutase (SOD) and catalase (CAT) activities, and the vitamin C, vitamin E, and non-protein thiol (NPSH) content in samples from patients with the relapsing-remitting form of MS (RRMS). The study population consisted of 29 RRMS patients and 29 healthy subjects. Twelve milliliters of blood was obtained from each individual and used for biochemical determinations. The results showed that δ-ALA-D and CAT activities were significantly increased, while SOD activity was decreased in the whole blood of RRMS patients compared to the control group (P vitamin C, vitamin E, NPSH, and vitamin D were significantly decreased in RRMS patients in relation to the healthy individuals (P vitamin D levels may contribute to the pathophysiology of MS. PMID:26690779

  10. Increased Cytokine and Nitric Oxide Levels in Serum of Dogs Experimentally Infected with Rangelia vitalii

    OpenAIRE

    Paim, Francine C; Aleksandro S. da Silva; Paim, Carlos Breno V.; Raqueli T. França; Costa, Márcio M.; Duarte, Marta M.M.F.; Sangoi, Manuela B.; Moresco, Rafael N.; Monteiro, Silvia G; Lopes, Sonia Terezinha A.

    2013-01-01

    This study aimed to measure the levels of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), interleukin 6 (IL-6), and nitrite/nitrate (NO x ) in serum of dogs experimentally infected with Rangelia vitalii. Twelve female mongrel dogs were divided into 2 groups; group A (uninfected controls) composed by healthy dogs (n=5) and group B consisting of dogs inoculated with R. vitalii (n=7). Animals were monitored by blood smear examinations, which showed intraeryth...

  11. Cytokine and nitric oxide levels in patients with sepsis--temporal evolvement and relation to platelet mitochondrial respiratory function.

    Directory of Open Access Journals (Sweden)

    Fredrik Sjövall

    Full Text Available BACKGROUND: The levels of nitric oxide (NO and various cytokines are known to be increased during sepsis. These signaling molecules could potentially act as regulators and underlie the enhancement of mitochondrial function described in the later phase of sepsis. Therefore, we investigated the correlation between observed changes in platelet mitochondrial respiration and a set of pro- and anti-inflammatory cytokines as well as NO plasma levels in patients with sepsis. METHODS AND RESULTS: Platelet mitochondrial respiration and levels of TNFα, MCP-1 (monocyte chemotactic protein-1, INFγ (interferon-γ, IL-1β, IL-4, IL-5, IL-6, IL-8, IL-10 and IL-17 and NO were analyzed in 38 patients with severe sepsis or septic shock at three time points during one week following admission to the ICU. Citrate synthase, mitochondrial DNA and cytochrome c were measured as markers of cellular mitochondrial content. All mitochondrial respiratory states increased over the week analyzed (p<0.001. IL-8 levels correlated with maximal mitochondrial respiration on day 6-7 (p = 0.02, r2 = 0.22 and was also higher in non-survivors compared to survivors on day 3-4 and day 6-7 (p = 0.03 respectively. Neither NO nor any of the other cytokines measured correlated with respiration or mortality. Cytochrome c levels were decreased at day 1-2 by 24±5% (p = 0.03 and returned towards values of the controls at the last two time points. Citrate synthase activity and mitochondrial DNA levels were similar to controls and remained constant throughout the week. CONCLUSIONS: Out of ten analyzed cytokines and nitric oxide, IL-8 correlated with the observed increase in mitochondrial respiration. This suggests that cytokines as well as NO do not play a prominent role in the regulation of platelet mitochondrial respiration in sepsis. Further, the respiratory increase was not accompanied by an increase in markers of mitochondrial content, suggesting a possible role for post

  12. Investigation of Homocystein Plasma Level in Cholestatic Rat and Its Effect on Nitric Oxide Secretion in Liver

    Directory of Open Access Journals (Sweden)

    N. Mirazi

    2005-04-01

    Full Text Available Homocystein (Hcy,one of the thio-amino acid is known as a risk factor in some cardiovascular diseases with releasing O2 radical . It has also been reported that; there is oxidative stress effects of Hcy in cholestasis. The aim of this study is to determine plasma Hcy alteration and nitric oxide (NO in liver and its effects on pathologic disfunction.In this study , 150 Spraque – Dawley male rats with 200 ± 20g body weight were used in the experiments and they were randomly divided in three control, SHAM and bile duct ligation (BDL groups (n= 10-12 . In 7th,14th,21st and 28th days cholestasis was observed in BDL group,the animal were anesthetized with ether and then blood samples were taken from heart directly and analysed for cystein , methionine by HPLC and HPLC-UV. Two hours before blood sampling , 40 and 100 mg/kg methionine were injected (I.P .All data are expressed as mean  SEM. Statistical evaluation of data performed by SPSS soft ware using analysis of variance (ANOVA followed by post hoc test. P-values less than 0.05 were considered statistically significant .The results suggest that billirubin and hepatic enzymes were significantly elevated in BDL rats compared with SHAM and controls (P<0.05. Homocystein concentration was significantly rised in 14th day in BDL group (P<0.05. The plasma cystein and methionine level were significantly elevated in BDL rats compared with SHAM and control groups ( p = 0.01 . Plasma nitrate / nitrite ratio were significantly increased in BDL rats compared with SHAM and control rats (P<0.05. With these data we suppose that some of the systemic oxidative stresses in BDL rat model of cholestasis contributes possibly through NO-dependent mechanisms disorders.

  13. Overexpression of Heat Shock Factor Gene HsfA3 Increases Galactinol Levels and Oxidative Stress Tolerance in Arabidopsis.

    Science.gov (United States)

    Song, Chieun; Chung, Woo Sik; Lim, Chae Oh

    2016-06-30

    Heat shock factors (Hsfs) are central regulators of abiotic stress responses, especially heat stress responses, in plants. In the current study, we characterized the activity of the Hsf gene HsfA3 in Arabidopsis under oxidative stress conditions. HsfA3 transcription in seedlings was induced by reactive oxygen species (ROS), exogenous hydrogen peroxide (H2O2), and an endogenous H2O2 propagator, 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB). HsfA3-overexpressing transgenic plants exhibited increased oxidative stress tolerance compared to untransformed wild-type plants (WT), as revealed by changes in fresh weight, chlorophyll fluorescence, and ion leakage under light conditions. The expression of several genes encoding galactinol synthase (GolS), a key enzyme in the biosynthesis of raffinose family oligosaccharides (RFOs), which function as antioxidants in plant cells, was induced in HsfA3 overexpressors. In addition, galactinol levels were higher in HsfA3 overexpressors than in WT under unstressed conditions. In transient transactivation assays using Arabidopsis leaf protoplasts, HsfA3 activated the transcription of a reporter gene driven by the GolS1 or GolS2 promoter. Electrophoretic mobility shift assays showed that GolS1 and GolS2 are directly regulated by HsfA3. Taken together, these findings provide evidence that GolS1 and GolS2 are directly regulated by HsfA3 and that GolS enzymes play an important role in improving oxidative stress tolerance by increasing galactinol biosynthesis in Arabidopsis. PMID:27109422

  14. Simultaneous involvement of a tungsten-containing aldehyde:ferredoxin oxidoreductase and a phenylacetaldehyde dehydrogenase in anaerobic phenylalanine metabolism.

    Science.gov (United States)

    Debnar-Daumler, Carlotta; Seubert, Andreas; Schmitt, Georg; Heider, Johann

    2014-01-01

    Anaerobic phenylalanine metabolism in the denitrifying betaproteobacterium Aromatoleum aromaticum is initiated by conversion of phenylalanine to phenylacetate, which is further metabolized via benzoyl-coenzyme A (CoA). The formation of phenylacetate is catalyzed by phenylalanine transaminase, phenylpyruvate decarboxylase, and a phenylacetaldehyde-oxidizing enzyme. The presence of these enzymes was detected in extracts of cells grown with phenylalanine and nitrate. We found that two distinct enzymes are involved in the oxidation of phenylacetaldehyde to phenylacetate, an aldehyde:ferredoxin oxidoreductase (AOR) and a phenylacetaldehyde dehydrogenase (PDH). Based on sequence comparison, growth studies with various tungstate concentrations, and metal analysis of the enriched enzyme, AOR was shown to be a tungsten-containing enzyme, necessitating specific cofactor biosynthetic pathways for molybdenum- and tungsten-dependent enzymes simultaneously. We predict from the genome sequence that most enzymes of molybdopterin biosynthesis are shared, while the molybdate/tungstate uptake systems are duplicated and specialized paralogs of the sulfur-inserting MoaD and the metal-inserting MoeA proteins seem to be involved in dedicating biosynthesis toward molybdenum or tungsten cofactors. We also characterized PDH biochemically and identified both NAD(+) and NADP(+) as electron acceptors. We identified the gene coding for the enzyme and purified a recombinant Strep-tagged PDH variant. The homotetrameric enzyme is highly specific for phenylacetaldehyde, has cooperative kinetics toward the substrate, and shows considerable substrate inhibition. Our data suggest that A. aromaticum utilizes PDH as the primary enzyme during anaerobic phenylalanine degradation, whereas AOR is not essential for the metabolic pathway. We hypothesize a function as a detoxifying enzyme if high aldehyde concentrations accumulate in the cytoplasm, which would lead to substrate inhibition of PDH.

  15. Coniferyl Aldehyde Ameliorates Radiation Intestine Injury via Endothelial Cell Survival

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ye Ji; Jung, Myung Gu; Lee, Yoonjin; Lee, Haejune [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yunsil [Ewha Woman' s Univ., Seoul (Korea, Republic of); Ko, Younggyu [Korea Univ., Seoul (Korea, Republic of)

    2014-05-15

    Cancer treatments related gastrointestinal toxicity has also been recognized as a significant economic burden. Especially, extensive apoptosis of microvascular endothelial cell of the lamina propria is the primary lesion initiating intestinal radiation damage after abdominal radiation therapy. Coniferyl aldehyde (CA) is phenolic compounds isolated from cork stoppers, and one of the major pyrolysis products of lignin. Shi H. was support for the empirical use of CA as a medicinal food for cardiovascular diseases. CA has positive effect in broad way but there is no consequence in radiation induced intestine damage. Here, we investigate effect of CA on small intestine after abdominal IR to mice in this study. In this study, CA increased the survival rate in C3H mice against 13.5 Gy abdominal IR. We found CA protects small intestine via preventing endothelial cell apoptosis and enhancing their angiogenic activity. CA also showed protective effect on crypt cell survival. Endothelial cell survival may affect crypt cell protection against IR. From this data, we concluded that CA is effective for protection against abdominal radiation injury. CA could ameliorate side-effect of radiation therapy.

  16. Does acute exposure to aldehydes impair pulmonary function and structure?

    Science.gov (United States)

    Abreu, Mariana de; Neto, Alcendino Cândido; Carvalho, Giovanna; Casquillo, Natalia Vasconcelos; Carvalho, Niedja; Okuro, Renata; Ribeiro, Gabriel C Motta; Machado, Mariana; Cardozo, Aléxia; Silva, Aline Santos E; Barboza, Thiago; Vasconcellos, Luiz Ricardo; Rodrigues, Danielle Araujo; Camilo, Luciana; Carneiro, Leticia de A M; Jandre, Frederico; Pino, Alexandre V; Giannella-Neto, Antonio; Zin, Walter A; Corrêa, Leonardo Holanda Travassos; Souza, Marcio Nogueira de; Carvalho, Alysson R

    2016-07-15

    Mixtures of anhydrous ethyl alcohol and gasoline substituted for pure gasoline as a fuel in many Brazilian vehicles. Consequently, the concentrations of volatile organic compounds (VOCs) such as ketones, other organic compounds, and particularly aldehydes increased in many Brazilian cities. The current study aims to investigate whether formaldehyde, acetaldehyde, or mixtures of both impair lung function, morphology, inflammatory and redox responses at environmentally relevant concentrations. For such purpose, C57BL/6 mice were exposed to either medical compressed air or to 4 different mixtures of formaldehyde and acetaldehyde. Eight hours later animals were anesthetized, paralyzed and lung mechanics and morphology, inflammatory cells and IL-1β, KC, TNF-α, IL-6, CCL2, MCP-1 contents, superoxide dismutase and catalalase activities were determined. The extra pulmonary respiratory tract was also analyzed. No differences could be detected between any exposed and control groups. In conclusion, no morpho-functional alterations were detected in exposed mice in relation to the control group. PMID:27102012

  17. Sodium borohydride removes aldehyde inhibitors for enhancing biohydrogen fermentation.

    Science.gov (United States)

    Lin, Richen; Cheng, Jun; Ding, Lingkan; Song, Wenlu; Zhou, Junhu; Cen, Kefa

    2015-12-01

    To enhance biohydrogen production from glucose and xylose in the presence of aldehyde inhibitors, reducing agent (i.e., sodium borohydride) was in situ added for effective detoxification. The detoxification efficiencies of furfural (96.7%) and 5-hydroxymethylfurfural (5-HMF, 91.7%) with 30mM NaBH4 were much higher than those of vanillin (77.3%) and syringaldehyde (69.3%). Biohydrogen fermentation was completely inhibited without detoxification, probably because of the consumption of nicotinamide adenine dinucleotide (NADH) by inhibitors reduction (R-CHO+2NADH→R-CH2OH+2NAD(+)). Addition of 30mM NaBH4 provided the reducing power necessary for inhibitors reduction (4R-CHO+NaBH4+2H2O→4R-CH2OH+NaBO2). The recovered reducing power in fermentation resulted in 99.3% recovery of the hydrogen yield and 64.6% recovery of peak production rate. Metabolite production and carbon conversion after detoxification significantly increased to 63.7mM and 81.9%, respectively. PMID:26342346

  18. Sodium borohydride removes aldehyde inhibitors for enhancing biohydrogen fermentation.

    Science.gov (United States)

    Lin, Richen; Cheng, Jun; Ding, Lingkan; Song, Wenlu; Zhou, Junhu; Cen, Kefa

    2015-12-01

    To enhance biohydrogen production from glucose and xylose in the presence of aldehyde inhibitors, reducing agent (i.e., sodium borohydride) was in situ added for effective detoxification. The detoxification efficiencies of furfural (96.7%) and 5-hydroxymethylfurfural (5-HMF, 91.7%) with 30mM NaBH4 were much higher than those of vanillin (77.3%) and syringaldehyde (69.3%). Biohydrogen fermentation was completely inhibited without detoxification, probably because of the consumption of nicotinamide adenine dinucleotide (NADH) by inhibitors reduction (R-CHO+2NADH→R-CH2OH+2NAD(+)). Addition of 30mM NaBH4 provided the reducing power necessary for inhibitors reduction (4R-CHO+NaBH4+2H2O→4R-CH2OH+NaBO2). The recovered reducing power in fermentation resulted in 99.3% recovery of the hydrogen yield and 64.6% recovery of peak production rate. Metabolite production and carbon conversion after detoxification significantly increased to 63.7mM and 81.9%, respectively.

  19. Control of the Reduction/Oxidation State of the High Level Waste Form in the Defense Waste Processing Facility at the Savannah River Site - 12451

    International Nuclear Information System (INIS)

    The Defense Waste Processing Facility at the Savannah River Site treats and immobilizes High Level Waste into a durable borosilicate glass for safe, permanent storage. Among the parameters important to the overall process is the reduction/oxidation state of the glass. Control strategies for the reduction/oxidation state of the glass have been developed and evolved over the last 20 years to provide a current strategy which is both accurate and robust. A description of the methodologies implemented to control, evaluate, and validate the reduction/oxidation state of the glass is discussed along with the impact of future facility changes (made to pursue a more aggressive program to empty High Level Waste tanks at the Savannah River Site) on the reduction/oxidation state of glass. The reduction/oxidation state of the glass is an important parameter to the operation of the Defense Waste Processing Facility. Control, evaluation, and validation of the reduction/oxidation state of the glass is of particular importance for melter operation. Melter feed which is too oxidizing can negatively impact production, while feed which is too reducing can result in catastrophic failure of the melter. Control strategies for the reduction/oxidation state of the glass have been developed and evolved over the last 20 years to provide a current strategy which is both accurate and robust. (authors)

  20. Uncatalyzed Condensation Reactions between Aromatic Aldehydes and Thiobarbituric Acid in Water

    Institute of Scientific and Technical Information of China (English)

    Bing Qin YANG; Jun LU; Min TIAN

    2003-01-01

    A series of 5-arylidene thiobarbituric acids were prepared from aromatic aldehydes and thiobarbituric acid in water without catalyst conditions in good yields. The structures were characterized by elemental analysis, IR and 1H NMR spectra.

  1. ARA-aldehyde and ABA-trans-diol in apple fruits

    Energy Technology Data Exchange (ETDEWEB)

    Rock, C.D.; Zeevaart, J.A.D. (Michigan State Univ., East Lansing (USA))

    1989-04-01

    We have isolated ABA-aldehyde and ABA-t-diol from postharvest apple fruits, cv. Granny Smith and confirmed their structure by GC-MS. These putative ABA biosynthetic precursors incorporate {sup 18}O to a similar degree as ABA during 48 hours under {sup 18}O{sub 2} atmospheres. The presence of significant amounts of ABA-aldehyde can explain the unique {sup 18}O labeling pattern of ABA in this tissue, where a majority of ABA molecules containing {sup 18}O is labeled in the 1{prime}-hydroxyl group and not in the side chain carboxyl group, the primary site of incorporation for stressed leaves. Exchange of the carbonyl oxygen of ABA-aldehyde with water would decrease {sup 18}O enrichment in the side chain. Results of {sup 18}O{sub 2} experiments and feeding studies using hexadeutero-ABA-aldehyde will be presented and the biosynthetic relationship of these compounds discussed.

  2. Ambient Ionic Liquids Used in the Reduction ofAldehydes and Ketones

    Institute of Scientific and Technical Information of China (English)

    Dan Qian XU; Shu Ping LUO; Bao You LIU; Zhen Yuan XU; Yin Chu SHEN

    2004-01-01

    The sodium borohydride reduction of aldehydes and ketones to corresponding alcohols has been accomplished via the use of ionic liquids. The alcohols are easily obtained with excellent yields and the ionic liquid BMImBF4 could be reused.

  3. Tetrabutylammonium fluoride promoted regiospecific reactions of trimethylsilyl-o-carborane with aldehydes

    International Nuclear Information System (INIS)

    Trimethylsilyl-o-carborane serves as o-carborane carbanion upon fluoride ion promoted reaction with carbonyl compounds. Thus, in the presence of tetrabutylammonium fluoride, trimethylsilyl-o-carborane undergoes facile, unprecedented, carbodesilylation with aromatic and aliphatic aldehydes. (author)

  4. Organocatalytic enantioselective Michael addition reactions of fluoromalonates with α,β-unsaturated aldehydes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new organocatalytic enantioselective Michael addition of α-fluoromalonate to enals has been developed.The process is efficiently catalyzed by readily available chiral diphenylpyrolinol TES ether under mild reaction conditions to afford versatile highly enantioenriched fluorinated aldehydes.

  5. A Direct Transformation of Aryl Aldehydes to Benzyl Iodides Via Reductive Iodination

    Energy Technology Data Exchange (ETDEWEB)

    Ruso, Jayaraman Sembian; Rajendiran, Nagappan; Kumaran, Rajendran Senthil [Univ. of Madras, Chennai (India)

    2014-02-15

    A facile transformation of aryl aldehydes to benzyl iodides through one-pot reductive iodination is reported. This protocol displays remarkable functional group tolerance and the title compound was obtained in good to excellent yield.

  6. Levels of Human Erythrocyte Membrane-Bound and Cytosolic Glycohydrolases Are Associated with Oxidative Stress in Erectile Dysfunction Patients

    Directory of Open Access Journals (Sweden)

    L. Massaccesi

    2014-01-01

    Full Text Available Oxidative stress (OS and production of NO, by endothelium nitric oxide synthetase (eNOS, are involved in the pathophysiology of erectile dysfunction (ED. Moreover, OS induces modifications of the physicochemical properties of erythrocyte (RBC plasma membranes and of the enzyme content of the same membranes. Due to their role in signalling early membrane alterations in OS-related pathologies, several plasma membrane and cytosolic glycohydrolases of human RBC have been proposed as new markers of cellular OS. In RBC, NOS can be activated and deactivated by phosphorylation/glycosylation. In this regulatory mechanism O-β-N-AcetylGlucosaminidase is a key enzyme. Cellular levels of O-GlcNAcylated proteins are related to OS; consequently dysfunctional eNOS O-GlcNAcylation seems to have a crucial role in ED. To elucidate the possible association between RBC glycohydrolases and OS, plasma hydroperoxides and antioxidant total defenses (Lag-time, cytosolic O-β-N-AcetylGlucosaminidase, cytosolic and membrane Hexosaminidase, membrane β-D-Glucuronidase, and α-D-Glucosidase have been studied in 39 ED patients and 30 controls. In ED subjects hydroperoxides and plasma membrane glycohydrolases activities are significantly increased whereas Lag-time values and cytosolic glycohydrolases activities are significantly decreased. These data confirm the strong OS status in ED patients, the role of the studied glycohydrolases as early OS biomarker and suggest their possible use as specific marker of ED patients, particularly in those undergoing nutritional/pharmacological antioxidant therapy.

  7. Strong interfacial polarization in ZnO decorated reduced-graphene oxide synthesized by molecular level mixing.

    Science.gov (United States)

    Jammula, Rama Krishna; Pittala, Suresh; Srinath, Sanyadhanam; Srikanth, Vadali V S S

    2015-07-14

    Globally, there is a great demand for energy storage materials and devices. In this context, charge storage capacitors are of great prominence. Metal oxide-graphene composites are excellent candidates for charge storage materials. This is because the dielectric properties of these composites can be controlled by the nature, dimensions and spatial distribution of the conductive components in these composites. ZnO decorated reduced-graphene oxide (r-GO) is synthesized and studied in this context. ZnO-r-GO composites are synthesized using molecular-level mixing. The composites are named as ZnO-0.1G, ZnO-0.2G and ZnO-0.3G in the order of increasing r-GO content. At 1 kHz, the dielectric permittivity (ε') values of ZnO-0.1G, ZnO-0.2G and ZnO-0.3G are nearly 11 (ε' = 114), 15 (ε' = 153) and 40 (ε' = 400) times greater than that of ZnO (ε' = 10). The strong interfacial polarization (Maxwell-Wagner polarization) in these composites is attributed to the presence of functional groups (which are polar in nature) on the r-GO sheets and also to the presence of lattice and/or topological defects in the r-GO. Temperature dependent electric modulus (M'') studies further confirm the observed interfacial polarization. PMID:26073161

  8. Expression of FOXO6 is Associated With Oxidative Stress Level and Predicts the Prognosis in Hepatocellular Cancer: A Comparative Study.

    Science.gov (United States)

    Chen, Hai-Yong; Chen, Yao-Min; Wu, Jian; Yang, Fu-Chun; Lv, Zhen; Xu, Xiao-Feng; Zheng, Shu-Sen

    2016-05-01

    The aim of this study was to explore the association of Forkhead box O6 (FOXO6) expression with oxidative stress level and prognosis of hepatocellular cancer (HCC).The case group included tissues of HCC from 128 patients who were hospitalized in Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery of First Affiliated Hospital, School of Medicine, Zhejiang University. The control group included normal liver tissues from 74 patients. RT-PCR and Western blot were used to test expressions of FOXO6, heme oxygenase (HO)-1, glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). Dihydroethidium (DHE) was dyed to observe reactive oxygen species (ROS) level. Immunohistochemistry was used to test FOXO6 expression. FOXO6 was silenced in HepG2 cells to detect cell proliferation and apoptosis. The expressions of ROS, HO-1, GPx, SOD, CAT, p27, and cyclin D1 were also detected to further explore the possible mechanism.The expressions of FOXO6, HO-1, GPx, SOD, and CAT in HCC tissue was significantly higher than those in normal and adjacent HCC tissues (P AFP) level, the presence or absence of hepatitis B surface antigen (HbsAg), and differentiation degree were related to FOXO6 expression level (all P AFP, and low degree of differentiation were all risk factors for prognosis in HCC (P <0.05). Compared with the blank group (C group, without transfection) and the negative control (NC) group, the mRNA expressions of ROS, FOXO6, HO-1, SOD, GPx, and CAT were decreased (P <0.05). si-RNA group had significantly decreased proliferation speed during 24 to 72 hours (P <0.05), whereas si-FOXO6 group had remarkably increased G0/G1 staged cells and decreased S-staged cells (P <0.05). The si-FOXO6 group showed notably increased apoptosis rate (P <0.05) and p27 expressions as well as decreased cyclin D1 expressions (P <0.05).FOXO6 was highly expressed in HCC tissue and was related to oxidative stress levels. Furthermore, FOXO6 expression

  9. Parallel Kinetic Resolution of Racemic Aldehydes by Use of Asymmetric Horner-Wadsworth-Emmons Reactions

    DEFF Research Database (Denmark)

    Pedersen, Torben Møller; Jensen, Jakob Feldthusen; Humble, Rikke Eva;

    2000-01-01

    A racemic aldehyde can undergo parallel kinetic resolution (PKR) by simultaneous reaction with two different chiral phosphonates, differing either in the structure of the chiral auxiliary or in the structure of the phosphoryl group (i.e., one (E)- and one (Z)-selective reagent). This strategy all...... allows conversion of a racemic aldehyde to two different, synthetically useful chiral products with essentially doubled material throughput and similar or improved selectivities as compared to conventional kinetic resolution....

  10. Garner’s aldehyde as a versatile intermediate in the synthesis of enantiopure natural products

    OpenAIRE

    Mikko Passiniemi; Koskinen, Ari M P

    2013-01-01

    Since its introduction to the synthetic community in 1984, Garner’s aldehyde has gained substantial attention as a chiral intermediate for the synthesis of numerous amino alcohol derivatives. This review presents some of the most successful carbon chain elongation reactions, namely carbonyl alkylations and olefinations. The literature is reviewed with particular attention on understanding how to avoid the deleterious epimerization of the existing stereocenter in Garner’s aldehyde.

  11. Chromatographic Methods for the Analyses of 2-Halofatty Aldehydes and Chlorohydrin Species of Lysophosphatidylcholine

    OpenAIRE

    Albert, Carolyn J; Anbukumar, Dhanalakshmi S.; Messner, Maria C.; Ford, David A.

    2008-01-01

    Plasmalogens are targeted by hypohalous acids resulting in the production of 2-chlorofatty aldehydes, 2-bromofatty aldehydes and chlorohydrin species of lysophosphatidylcholine. These novel lipids have required the development of techniques for their purification and quantification. Thin layer chromatography, high performance liquid chromatography and gas chromatography of these lipids and their derivatives have provided a battery of tools for their analyses. These lipids have been quantified...

  12. Flavour release of aldehydes and diacetyl in oil/water systems

    DEFF Research Database (Denmark)

    Haahr, Anne-Mette; Bredie, W. L. P.; Stahnke, Louise Heller;

    2000-01-01

    The concentration- and time-dependent release of three C-6-aldehydes, six C-9-aldehydes and diacetyl was studied in model systems. The systems were water, rapeseed oil and oil-in-water emulsions. Dynamic headspace sampling was used to collect the volatile compounds. In the concentration...... compounds was dependent on the chain length, the degree of unsaturation as well as the characteristics of the model system. (C) 2000 Elsevier Science Ltd. All rights reserved....

  13. An Improved Protocol for the Aldehyde Olefination Reaction Using (bmim ( as Reaction Medium

    Directory of Open Access Journals (Sweden)

    Vivek Srivastava

    2013-01-01

    Full Text Available [Ru(CODCl2]/CuCl2·2H2O/LiCl catalytic system works efficiently in ionic liquid media for aldehyde olefination reaction. It offers good yield and selectivity with the added advantage of 5 times recyclability for [Ru(CODCl2] /CuCl2·2H2O/LiCl catalytic system. We also successfully reduced the reaction time from 12 hours to 9 hours for the aldehyde olefination reaction.

  14. Zinc oxide at low supplementation level improves productive performance and health status of piglets.

    Science.gov (United States)

    Morales, J; Cordero, G; Piñeiro, C; Durosoy, S

    2012-12-01

    Use of ZnO at high doses (3000 ppm) for diarrhea prophylaxis in piglets is widely extended in postweaning Spanish diets, in compliance with the national veterinary regulation. However, European feed legislation limits total dietary Zn to a maximum of 150 mg/kg of complete feed. The objective of this study was to compare a new potentiated form of ZnO, HiZox (Animine), at nutritional level (150 ppm) with pharmacological dosage (3000 ppm) of regular ZnO in starter diets on the productive performance and health status of piglets in a medium-low health status farm. A total of 144 pigs at weaning (28 d of age) were distributed in 6 piglets/pen and 12 pens/treatment. In the prestarter phase (28 to 42 d of age), all pigs received the same commercial feed, including 3000 ppm ZnO. In the starter phase (42 to 63 d of age) (T1) included 3000 ppm of regular ZnO (2500 ppm Zn), and (T2) was supplemented with 110 ppm Zn from potentiated ZnO (HiZox). Average daily feed intake, ADG, G:F, and pig-MAP serum concentration, an acute phase protein commonly used as unspecific biomarker of disease or other acute phase reactions, were measured at 42 and 63 d of life. Pen of 6 piglets was the experimental unit and data were analyzed using the GLM procedure of SAS version 9.0. Piglets fed with T2-HiZox had improved ADG and G:F (P < 0.001) compared to piglets fed with T1-ZnO. In addition, at 63 d of age, the T2 group had a lower pig-MAP serum concentration than T1 group (1.71 vs. 0.95 μg/mL; P < 0.05) indicating higher health status in the T2 group. In conclusion, in low-medium sanitary conditions and in compliance with European regulation, HiZox significantly increased piglet growth compared to pharmacological dosage of regular ZnO in the starter phase. This can be explained by a better health of pigs expressed by a lower level of inflammatory protein pig-MAP. PMID:23365402

  15. Probing the density of states of two-level tunneling systems in silicon oxide films using superconducting lumped element resonators

    Energy Technology Data Exchange (ETDEWEB)

    Skacel, S. T. [Physikalisches Institut, Karlsruher Institut für Technologie, Wolfgang-Gaede-Straße 1, D-76131 Karlsruhe (Germany); Institut für Mikro- und Nanoelektronische Systeme, Karlsruher Institut für Technologie, Hertzstraße 16, D-76187 Karlsruhe (Germany); Kaiser, Ch.; Wuensch, S.; Siegel, M. [Institut für Mikro- und Nanoelektronische Systeme, Karlsruher Institut für Technologie, Hertzstraße 16, D-76187 Karlsruhe (Germany); Rotzinger, H.; Lukashenko, A.; Jerger, M.; Weiss, G. [Physikalisches Institut, Karlsruher Institut für Technologie, Wolfgang-Gaede-Straße 1, D-76131 Karlsruhe (Germany); Ustinov, A. V. [Physikalisches Institut, Karlsruher Institut für Technologie, Wolfgang-Gaede-Straße 1, D-76131 Karlsruhe (Germany); Russian Quantum Center, 100 Novaya St., Skolkovo, Moscow Region 143025 (Russian Federation)

    2015-01-12

    We have investigated dielectric losses in amorphous silicon oxide (a-SiO) thin films under operating conditions of superconducting qubits (mK temperatures and low microwave powers). For this purpose, we have developed a broadband measurement setup employing multiplexed lumped element resonators using a broadband power combiner and a low-noise amplifier. The measured temperature and power dependences of the dielectric losses are in good agreement with those predicted for atomic two-level tunneling systems (TLS). By measuring the losses at different frequencies, we found that the TLS density of states is energy dependent. This had not been seen previously in loss measurements. These results contribute to a better understanding of decoherence effects in superconducting qubits and suggest a possibility to minimize TLS-related decoherence by reducing the qubit operation frequency.

  16. Identification of Potential Calorie Restriction-Mimicking Yeast Mutants with Increased Mitochondrial Respiratory Chain and Nitric Oxide Levels

    Directory of Open Access Journals (Sweden)

    Bin Li

    2011-01-01

    Full Text Available Calorie restriction (CR induces a metabolic shift towards mitochondrial respiration; however, molecular mechanisms underlying CR remain unclear. Recent studies suggest that CR-induced mitochondrial activity is associated with nitric oxide (NO production. To understand the role of mitochondria in CR, we identify and study Saccharomyces cerevisiae mutants with increased NO levels as potential CR mimics. Analysis of the top 17 mutants demonstrates a correlation between increased NO, mitochondrial respiration, and longevity. Interestingly, treating yeast with NO donors such as GSNO (S-nitrosoglutathione is sufficient to partially mimic CR to extend lifespan. CR-increased NO is largely dependent on mitochondrial electron transport and cytochrome c oxidase (COX. Although COX normally produces NO under hypoxic conditions, CR-treated yeast cells are able to produce NO under normoxic conditions. Our results suggest that CR may derepress some hypoxic genes for mitochondrial proteins that function to promote the production of NO and the extension of lifespan.

  17. Syzygium cumini reduces oxidative stress and matrix metalloproteinase-2 level in endothelial cells induced by plasma from preeclamptic patients

    Directory of Open Access Journals (Sweden)

    Yumi Abimulyani

    2014-06-01

    Full Text Available Objective: This study aimed to investigate whether an ethanolic extract of Syzygium cumini is able to decrease lipid peroxidation and matrix metalloproteinase (MMP-2 expression in endothelial cells exposed to plasma from preeclamptic patients. Methods: Endothelial cells were obtained from human umbilical vascular endothelial cells. At confluency, endothelial cells were divided into five groups, which included control (untreated, endothelial cells exposed to 2% plasma from preeclamptic patients (PP, endothelial cells exposed to PP in the presence of ethanolic extract of S.cumini (PP+SC at the doses of 100, 200 and 400 ppm. Analysis of malondialdehyde (MDA level as a marker of lipid peroxidation was done colorimetrically. Analysis of MMP-2 level was done by enzyme linked immunosorbent assay (ELISA technically. Results: This increase in MDA was significantly attenuated by both the 200 and 400 ppm treatments of S.cumini extract. Plasma from PP significantly increased MMP-2 levels compared to untreated cells. This increase in MMP-2 was significantly attenuated by the 200 and 400 ppm doses of the extract. Conclusion: In conclusion, Syzygium cumini extract prohibits the increase in oxidative stress and MMP-2 in endothelial cells induced by plasma from preeclamptic patients. Therefore this may provide a natural therapy for attenuating the maternal endothelial dysfunction found in this disease. [J Exp Integr Med 2014; 4(2.000: 89-92

  18. Calculation of contact angles at triple phase boundary in solid oxide fuel cell anode using the level set method

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xiaojun [Institute of Industrial Science, The University of Tokyo (Japan); Hasegawa, Yosuke [Institute of Industrial Science, The University of Tokyo (Japan); CREST, JST (Japan); Kohno, Haruhiko [Department of Mechanical Information Science and Technology, Kyushu Institute of Technology (Japan); Jiao, Zhenjun [Institute of Industrial Science, The University of Tokyo (Japan); CREST, JST (Japan); Hayakawa, Koji [Institute of Industrial Science, The University of Tokyo (Japan); Okita, Kohei [College of Industrial Technology, Nihon University (Japan); Shikazono, Naoki, E-mail: shika@iis.u-tokyo.ac.jp [Institute of Industrial Science, The University of Tokyo (Japan); CREST, JST (Japan)

    2014-10-15

    A level set method is applied to characterize the three dimensional structures of nickel, yttria stabilized zirconia and pore phases in solid oxide fuel cell anode reconstructed by focused ion beam-scanning electron microscope. A numerical algorithm is developed to evaluate the contact angles at the triple phase boundary based on interfacial normal vectors which can be calculated from the signed distance functions defined for each of the three phases. Furthermore, surface tension force is estimated from the contact angles by assuming the interfacial force balance at the triple phase boundary. The average contact angle values of nickel, yttria stabilized zirconia and pore are found to be 143°–156°, 83°–138° and 82°–123°, respectively. The mean contact angles remained nearly unchanged after 100 hour operation. However, the contact angles just after reduction are different for the cells with different sintering temperatures. In addition, standard deviations of the contact angles are very large especially for yttria stabilized zirconia and pore phases. The calculated surface tension forces from mean contact angles were close to the experimental values found in the literature. Slight increase of surface tensions of nickel/pore and nickel/yttria stabilized zirconia were observed after operation. Present data are expected to be used not only for the understanding of the degradation mechanism, but also for the quantitative prediction of the microstructural temporal evolution of solid oxide fuel cell anode. - Highlights: • A level set method is applied to characterize the 3D structures of SOFC anode. • A numerical algorithm is developed to evaluate the contact angles at the TPB. • Surface tension force is estimated from the contact angles. • The average contact angle values are found to be 143o-156o, 83o-138o and 82o-123o. • Present data are expected to understand degradation and predict evolution of SOFC.

  19. Atmospheric oxygen levels, anaerobic methane oxidation, and the coupling of the global COS cycles by sulfate reduction

    Science.gov (United States)

    Wortmann, U. G.; Chernyavsky, B. M.

    2007-12-01

    Changes in the partitioning between the reduced and oxidized reservoirs of carbon and sulfur are the dominant control on atmospheric oxygen levels, and the partitioning itself depends to a large degree on microbial redox processes remineralizing organic matter (OM). However, the controls of organic matter preservation in marine sediments are one of the most complex and controversial issues in contemporary biochemistry. Knowledge how the transition from one electron acceptor to another affects OM remineralization rates is scant even for the transition from aerobic to anaerobic respiration. Much less is known about the transition from anaerobic respiration to fermentation. Although the individual pathways of methane generation are known, our understanding of the complex interactions between different bacterial groups remains limited, resulting in considerable difficulties to resolve these questions in microcosm experiments. Here we show that a dramatic drop in seawater sulfate concentrations during the Early Cretaceous (Wortmann & Chernyavsky, Nature 2007) resulted in a global breakdown of microbial sulfate reduction in the marine subsurface biosphere. This event resulted in a positive excursion of the global δ13C-value, suggesting that organic matter remineralization rates dropped by more than 50%. This implies that the methanogenic microbial community was unable to increase their metabolic rates, despite the increased supply of organic matter. the reduced availability of sulfate for anaerobic methane oxidation did not increase the flux of isotopically light carbon into the ocean/atmosphere system. We therefore speculate that the capacity of marine methanogenic ecosystems to synthesize extracellular enzymes to hydrolyze organic matter is specific to the prevailing type of organic matter. This results in a positive coupling of the metabolic activity of both ecosystems, which in turn is a necessary prerequisite to decouple reduced carbon and sulfur burial, a key

  20. Is the Oxidative DNA Damage Level of Human Lymphocyte Correlated with the Antioxidant Capacity of Serum or the Base Excision Repair Activity of Lymphocyte?

    Directory of Open Access Journals (Sweden)

    Yi-Chih Tsai

    2013-01-01

    Full Text Available A random screening of human blood samples from 24 individuals of nonsmoker was conducted to examine the correlation between the oxidative DNA damage level of lymphocytes and the antioxidant capacity of serum or the base excision repair (BER activity of lymphocytes. The oxidative DNA damage level was measured with comet assay containing Fpg/Endo III cleavage, and the BER activity was estimated with a modified comet assay including nuclear extract of lymphocytes for enzymatic cleavage. Antioxidant capacity was determined with trolox equivalent antioxidant capacity assay. We found that though the endogenous DNA oxidation levels varied among the individuals, each individual level appeared to be steady for at least 1 month. Our results indicate that the oxidative DNA damage level is insignificantly or weakly correlated with antioxidant capacity or BER activity, respectively. However, lymphocytes from carriers of Helicobacter pylori (HP or Hepatitis B virus (HBV tend to give higher levels of oxidative DNA damage (P<0.05. Though sera of this group of individuals show no particular tendency with reduced antioxidant capacity, the respective BER activities of lymphocytes are lower in average (P<0.05. Thus, reduction of repair activity may be associated with the genotoxic effect of HP or HBV infection.

  1. Molecular Response to Toxic Diatom-Derived Aldehydes in the Sea Urchin Paracentrotus lividus

    Directory of Open Access Journals (Sweden)

    Stefano Varrella

    2014-04-01

    Full Text Available Diatoms are dominant photosynthetic organisms in the world’s oceans and represent a major food source for zooplankton and benthic filter-feeders. However, their beneficial role in sustaining marine food webs has been challenged after the discovery that they produce secondary metabolites, such as polyunsaturated aldehydes (PUAs, which negatively affect the reproductive success of many invertebrates. Here, we report the effects of two common diatom PUAs, heptadienal and octadienal, which have never been tested before at the molecular level, using the sea urchin, Paracentrotus lividus, as a model organism. We show that both PUAs are able to induce teratogenesis (i.e., malformations, as already reported for decadienal, the better-studied PUA of this group. Moreover, post-recovery experiments show that embryos can recover after treatment with all three PUAs, indicating that negative effects depend both on PUA concentrations and the exposure time of the embryos to these metabolites. We also identify the time range during which PUAs exert the greatest effect on sea urchin embryogenesis. Finally, we report the expression levels of thirty one genes (having a key role in a broad range of functional responses, such as stress, development, differentiation, skeletogenesis and detoxification processes in order to identify the common targets affected by PUAs and their correlation with morphological abnormalities. This study opens new perspectives for understanding how marine organisms afford protection from environmental toxicants through an integrated network of genes.

  2. Drying of linseed oil paints: the effects of substrate on the emission of aldehydes.

    Science.gov (United States)

    Fjällström, P; Andersson, B; Nilsson, C

    2003-09-01

    The effect of substrate on the emission of aldehydes from linseed oil paint was investigated. Plates of glass, fiberboard, gypsum board, lime mortar and wood lath were painted, and then placed into emission chambers. Samples were collected every eighth hour over 10 days with 2,4-dinitrophenylhydrazin samplers. Analysis was performed with liquid chromatography/UV-detection and mass spectrometry. Paint applied on gypsum board gave the highest total amount of emitted carbonyls, and that on wood lath gave the least. Painted glass had the highest contribution of unsaturated species, and lime mortar, the lowest. Lime mortar also had the highest momentary levels of a single species, 443 nmol/h/m2 of propanal, while fiberboard peaked at only 123 nmol/h/m2 of propanal. In turn, the emission from the painted fiberboard had the slowest decline, and thus at the end of the experiment the highest levels. All substrates gave an emission that peaked within 16 h. PMID:12950591

  3. Accurate determination of aldehydes in amine catalysts or amines by 2,4-dinitrophenylhydrazine derivatization.

    Science.gov (United States)

    Barman, Bhajendra N

    2014-01-31

    Carbonyl compounds, specifically aldehydes, present in amine catalysts or amines are determined by reversed-phase liquid chromatography using ultraviolet detection of their corresponding 2,4-dinitrophenylhydrazones. The primary focus has been to establish optimum conditions for determining aldehydes accurately because these add exposure concerns when the amine catalysts are used to manufacture polyurethane products. Concentrations of aldehydes determined by this method are found to vary with the pH of the aqueous amine solution and the derivatization time, the latter being problematic when the derivatization reaction proceeds slowly and not to completion in neutral and basic media. Accurate determination of aldehydes in amines through derivatization can be carried out at an effective solution pH of about 2 and with derivatization time of 20min. Hydrochloric acid has been used for neutralization of an amine. For complete derivatization, it is essential to protonate all nitrogen atoms in the amine. An approach for the determination of an adequate amount of acid needed for complete derivatization has been described. Several 0.2M buffer solutions varying in pH from 4 to 8 have also been used to make amine solutions for carrying out derivatization of aldehydes. These solutions have effective pHs of 10 or higher and provide much lower aldehyde concentrations compared to their true values. Mechanisms for the formation of 2,4-dinitrophenylhydrazones in both acidic and basic media are discussed. PMID:24411140

  4. Effect of selected aldehydes on the growth and fermentation of ethanologenic Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Zaldivar, J.; Ingram, L.O. [Univ. of Florida, Gainesville (United States). Dept. of Microbiology and Cell Science; Martinez, A. [Univ. of Florida, Gainesville (United States). Dept. of Microbiology and Cell Science]|[Univ. Nacional Autonoma de Mexico (Mexico). Inst. de Biotecnologia

    1999-10-05

    Bioethanol production from lignocellulosic raw-materials requires the hydrolysis of carbohydrate polymers into a fermentable syrup. During the hydrolysis of hemicellulose with dilute acid, a variety of toxic compounds are produced such as soluble aromatic aldehydes from lignin and furfural from pentose destruction. In this study, the authors have investigated the toxicity of representative aldehydes (furfural, 5-hydroxymethlyfurfural, 4-hydroxybenzaldehyde, syringaldehyde, and vanillin) as inhibitors of growth and ethanol production by ethanologenic derivatives of Escherichia coli B (strains K011 and LY01). Aromatic aldyhydes were at least twice as toxic as furfural of 5-hydroxymethylfurfural on a weight basis. The toxicities of all aldehydes (and ethanol) except furfural were additive when tested in binary combinations. In all cases, combinations with furfural were unexpectedly toxic. Although the potency of these aldehydes was directly related to hydrophobicity indicating a hydrophobic site of action, none caused sufficient membrane damage to allow the leakage of intracellular magnesium even when present at sixfold the concentrations required for growth inhibition. Of the aldehydes tested, only furfural strongly inhibited ethanol production in vitro. A comparison with published results for other microorganisms indicates that LY01 is equivalent or more resistant than other biocatalysts to the aldehydes examined in this study.

  5. Detoxification potential and expression analysis of eutypine reducing aldehyde reductase (VrALR) during progressive drought and recovery in Vigna radiata (L.) Wilczek roots.

    Science.gov (United States)

    Sengupta, Debashree; Mudalkar, Shalini; Reddy, Attipalli R

    2012-10-01

    Generation of reactive oxygen species (ROS) in plants is an inevitable consequence of adverse environmental cues and the ability to detoxify deleterious by-products of ROS-mediated oxidation reactions reflect an important defence strategy to combat abiotic stress. Here, we have cloned the eutypine reducing aldehyde reductase gene (VrALR) from Vigna radiata (L.) Wilczek roots. We have expressed and purified the VrALR protein and analyzed its enzyme kinetic parameters and catalytic efficiency with three different substrates to confirm its identity. The functional characterization of this enzyme was unravelled through heterologous expression of the gene in Escherichia coli BL21 and an oxidative stress-sensitive Saccharomyces cerevisiae mutant strain, W3O3-1-A. Finally, the endogenous VrALR enzyme activity and the mRNA expression patterns of the VrALR gene in the roots of V. radiata in response to progressive drought stress in vivo was studied to correlate the ROS-detoxifying role of this important enzyme under the influence of progressive drought stress. Our results, for the first time, demonstrate that eutypine reducing VrALR provides varying degree of stress tolerance in bacteria, yeast systems and also plays a promising protective role against oxidative stress in V. radiata roots during gradual water deprivation. The present study provides an unequivocal evidence to understand the crucial role of aldehyde reductase ROS-detoxifying system which is highly essential for developing stress tolerance in economically important crop plants. PMID:22837052

  6. Oxidative desulfurization of dibenzothiophene with molecular oxygen using emulsion catalysis.

    Science.gov (United States)

    Lü, Hongying; Gao, Jinbo; Jiang, Zongxuan; Yang, Yongxing; Song, Bo; Li, Can

    2007-01-14

    Dibenzothiophene (DBT) is oxidized to the corresponding sulfoxide and sulfone in an emulsion system (W/O) composed of polyoxometalate anion [C(18)H(37)N(CH(3))3](5)[PV(2)Mo(10)O(40)] as both the surfactant and catalyst, using molecular oxygen as the oxidant and aldehyde as the sacrificial agent under mild conditions. PMID:17180229

  7. Lipid Oxidation Promotes Acrylamide Formation in Fat-Rich Systems

    NARCIS (Netherlands)

    Capuano, Edoardo

    2016-01-01

    Evidence from model systems suggests that lipid oxidation can contribute to acrylamide (AA) formation through the generation of secondary lipid oxidation carbonyl products, mainly aldehydes, which are able to degrade asparagine to AA. In this respect, factors affecting the extent of lipid oxidati

  8. Characterizing dose response relationships: Chronic gamma radiation in Lemna minor induces oxidative stress and altered polyploidy level.

    Science.gov (United States)

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-12-01

    The biological effects and interactions of different radiation types in plants are still far from understood. Among different radiation types, external gamma radiation treatments have been mostly studied to assess the biological impact of radiation toxicity in organisms. Upon exposure of plants to gamma radiation, ionisation events can cause, either directly or indirectly, severe biological damage to DNA and other biomolecules. However, the biological responses and oxidative stress related mechanisms under chronic radiation conditions are poorly understood in plant systems. In the following study, it was questioned if the Lemna minor growth inhibition test is a suitable approach to also assess the radiotoxicity of this freshwater plant. Therefore, L. minor plants were continuously exposed for seven days to 12 different dose rate levels covering almost six orders of magnitude starting from 80 μGy h(-1) up to 1.5 Gy h(-1). Subsequently, growth, antioxidative defence system and genomic responses of L. minor plants were evaluated. Although L. minor plants could survive the exposure treatment at environmental relevant exposure conditions, higher dose rate levels induced dose dependent growth inhibitions starting from approximately 27 mGy h(-1). A ten-percentage growth inhibition of frond area Effective Dose Rate (EDR10) was estimated at 95 ± 7 mGy h(-1), followed by 153 ± 13 mGy h(-1) and 169 ± 12 mGy h(-1) on fresh weight and frond number, respectively. Up to a dose rate of approximately 5 mGy h(-1), antioxidative enzymes and metabolites remained unaffected in plants. A significant change in catalase enzyme activity was found at 27 mGy h(-1) which was accompanied with significant increases of other antioxidative enzyme activities and shifts in ascorbate and glutathione content at higher dose rate levels, indicating an increase in oxidative stress in plants. Recent plant research hypothesized that environmental genotoxic stress conditions

  9. Oxidation of Alcohols Catalyzed by Ruthenium Complexes with Iodosylbenzene as Oxidant

    Institute of Scientific and Technical Information of China (English)

    Zi Qiang LEI; Qiao Xiang KANG; Xiang Zhen BAI; Zhi Wang YANG; Qing Hua ZHANG

    2005-01-01

    Five ruthenium complexes such as Phen-Ru-Phen, Phen-Ru-Bipy, Phen-Ru-Quin,Quin-Ru-Quin and Bipy-Ru-Quin (where Phen=1, 10-phenanthroline, Quin=8-hydroxyquinoline,Bipy=2, 2′-bipyridine) were synthesized and used as catalysts for the oxidation of benzylic and primary aliphatic alcohols with iodosylbenzene as oxidant. The oxidations were carried out at room temperature, affording the corresponding aldehydes and ketones with high selectivity.

  10. Safrole oxide induced human umbilical vein vascular endothelial cell differentiation into neuron-like cells by depressing the reactive oxygen species level at the low concentration.

    Science.gov (United States)

    Su, Le; Zhao, Jing; Zhao, Bao Xiang; Miao, Jun Ying; Yin, De Ling; Zhang, Shang Li

    2006-02-01

    Previously, we found that 5-25 microg/ml safrole oxide could inhibit apoptosis and dramatically make a morphological change in human umbilical vein vascular endothelial cells (HUVECs). But the possible mechanism by which safrole oxide function is unknown. To answer this question, in this study, we first investigated the effects of it on the activity of nitric oxide synthetase (NOS), the expressions of Fas and integrin beta4, which play important roles in HUVEC growth and apoptosis, respectively. The results showed that, at the low concentration (10 microg/ml), safrole oxide had no effects on NOS activity and the expressions of Fas and integrin beta4. Then, we investigated whether HUVECs underwent differentiation. We examined the expressions of neuron-specific enolase (NSE) and neurofilament-L (NF-L). Furthermore, we analyzed the changes of intracellular reactive oxygen species (ROS). After 10 h of treatment with 10 microg/ml safrole oxide, some HUVECs became neuron-like cells in morphology, and intensively displayed positive NSE and NF-L. Simultaneously, ROS levels dramatically decreased during HUVECs differentiation towards neuron-like cells. At the low concentration, safrole oxide induced HUVECs differentiation into neuron-like cells. Furthermore, our data suggested that safrole oxide might perform this function by depressing intracellular ROS levels instead of by affecting cell growth or apoptosis signal pathways.

  11. Oxidative Degradation of the Monolayer of 1-Palmitoyl-2-Oleoyl-sn-Glycero-3-Phosphocholine (POPC) in Low-Level Ozone.

    Science.gov (United States)

    Qiao, Lin; Ge, Aimin; Liang, Yimin; Ye, Shen

    2015-11-01

    Ambient ozone is a common pollutant in the atmosphere that has an extremely high oxidative ability, can dramatically change the structure and functionality of biomolecules, and is harmful to public health. However, the knowledge about the influence of low-level ozone is still very limited at a molecular level. In the present study, the monolayer of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC, 16:0-18:1 PC) as well as its binary mixed monolayer with 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC, 16:0 PC), which are widely found in many biological systems, have been systematically investigated in a low-level ozone environment (20 ± 10 ppb), by π-A isotherm, sum frequency generation (SFG) vibrational spectroscopy, and atomic force microscopy (AFM). Our results demonstrate that the POPC monolayer is unstable and the C═C moieties in the oleyl chain are selectively oxidized by the low-level ozone. The oxidized lipids from POPC initially remain and reorientate the hydrophilic portion to the water surface and gradually dissolve into the aqueous solution. One should take great caution when using unsaturated lipid molecules to avoid their possible oxidation in the ambient environment. The present study expands and deepens our insights into the oxidation mechanism of unsaturated lipids at a molecular level.

  12. Health-Beneficial Phenolic Aldehyde in Antigonon leptopus Tea

    Directory of Open Access Journals (Sweden)

    Vanisree Mulabagal

    2011-01-01

    Full Text Available Tea prepared from the aerial parts of Antigonon leptopus is used as a remedy for cold and pain relief in many countries. In this study, A. leptopus tea, prepared from the dried aerial parts, was evaluated for lipid peroxidation (LPO and cyclooxygenase (COX-1 and COX-2 enzyme inhibitory activities. The tea as a dried extract inhibited LPO, COX-1 and COX-2 enzymes by 78%, 38% and 89%, respectively, at 100 g/mL. Bioassay-guided fractionation of the extract yielded a selective COX-2 enzyme inhibitory phenolic aldehyde, 2,3,4-trihydroxy benzaldehyde. Also, it showed LPO inhibitory activity by 68.3% at 6.25 g/mL. Therefore, we have studied other hydroxy benzaldehydes and their methoxy analogs for LPO, COX-1 and COX-2 enzymes inhibitory activities and found that compound 1 gave the highest COX-2 enzyme inhibitory activity as indicated by a 50% inhibitory concentration (IC50 at 9.7 g/mL. The analogs showed only marginal LPO activity at 6.25 g/mL. The hydroxy analogs 6, 7 and 9 showed 55%, 61% and 43% of COX-2 inhibition at 100 g/mL. However, hydroxy benzaldehydes 3 and 12 showed selective COX-1 inhibition while compounds 4 and 10 gave little or no COX-2 enzyme inhibition at 100 g/mL. At the same concentration, compounds 14, 21 and 22 inhibited COX-1 by 83, 85 and 70%, respectively. Similarly, compounds 18, 19 and 23 inhibited COX-2 by 68%, 72% and 70%, at 100 g/mL. This is the first report on the isolation of compound 1 from A. leptopus tea with selective COX-2 enzyme and LPO inhibitory activities.

  13. Residues that influence coenzyme preference in the aldehyde dehydrogenases.

    Science.gov (United States)

    González-Segura, Lilian; Riveros-Rosas, Héctor; Julián-Sánchez, Adriana; Muñoz-Clares, Rosario A

    2015-06-01

    To find out the residues that influence the coenzyme preference of aldehyde dehydrogenases (ALDHs), we reviewed, analyzed and correlated data from their known crystal structures and amino-acid sequences with their published kinetic parameters for NAD(P)(+). We found that the conformation of the Rossmann-fold loops participating in binding the adenosine ribose is very conserved among ALDHs, so that coenzyme specificity is mainly determined by the nature of the residue at position 195 (human ALDH2 numbering). Enzymes with glutamate or proline at 195 prefer NAD(+) because the side-chains of these residues electrostatically and/or sterically repel the 2'-phosphate group of NADP(+). But contrary to the conformational rigidity of proline, the conformational flexibility of glutamate may allow NADP(+)-binding in some enzymes by moving the carboxyl group away from the 2'-phosphate group, which is possible if a small neutral residue is located at position 224, and favored if the residue at position 53 interacts with Glu195 in a NADP(+)-compatible conformation. Of the residues found at position 195, only glutamate interacts with the NAD(+)-adenosine ribose; glutamine and histidine cannot since their side-chain points are opposite to the ribose, probably because the absence of the electrostatic attraction by the conserved nearby Lys192, or its electrostatic repulsion, respectively. The shorter side-chains of other residues-aspartate, serine, threonine, alanine, valine, leucine, or isoleucine-are distant from the ribose but leave room for binding the 2'-phosphate group. Generally, enzymes having a residue different from Glu bind NAD(+) with less affinity, but they can also bind NADP(+) even sometimes with higher affinity than NAD(+), as do enzymes containing Thr/Ser/Gln195. Coenzyme preference is a variable feature within many ALDH families, consistent with being mainly dependent on a single residue that apparently has no other structural or functional roles, and therefore can

  14. The effect of peroxynitrite decomposition catalyst MnTBAP on aldehyde dehydrogenase-2 nitration by organic nitrates: role in nitrate tolerance.

    Science.gov (United States)

    Mollace, Vincenzo; Muscoli, Carolina; Dagostino, Concetta; Giancotti, Luigino Antonio; Gliozzi, Micaela; Sacco, Iolanda; Visalli, Valeria; Gratteri, Santo; Palma, Ernesto; Malara, Natalia; Musolino, Vincenzo; Carresi, Cristina; Muscoli, Saverio; Vitale, Cristiana; Salvemini, Daniela; Romeo, Francesco

    2014-11-01

    Bioconversion of glyceryl trinitrate (GTN) into nitric oxide (NO) by aldehyde dehydrogenase-2 (ALDH-2) is a crucial mechanism which drives vasodilatory and antiplatelet effect of organic nitrates in vitro and in vivo. Oxidative stress generated by overproduction of free radical species, mostly superoxide anions and NO-derived peroxynitrite, has been suggested to play a pivotal role in the development of nitrate tolerance, though the mechanism still remains unclear. Here we studied the free radical-dependent impairment of ALDH-2 in platelets as well as vascular tissues undergoing organic nitrate ester tolerance and potential benefit when using the selective peroxynitrite decomposition catalyst Mn(III) tetrakis (4-Benzoic acid) porphyrin (MnTBAP). Washed human platelets were made tolerant to nitrates via incubation with GTN for 4h. This was expressed by attenuation of platelet aggregation induced by thrombin (40U/mL), an effect accompanied by GTN-related induction of cGMP levels in platelets undergoing thrombin-induced aggregation. Both effects were associated to attenuated GTN-induced nitrite formation in platelets supernatants and to prominent nitration of ALDH-2, the GTN to NO metabolizing enzyme, suggesting that GTN tolerance was associated to reduced NO formation via impairment of ALDH-2. These effects were all antagonized by co-incubation of platelets with MnTBAP, which restored GTN-induced responses in tolerant platelets. Comparable effect was found under in in vivo settings. Indeed, MnTBAP (10mg/kg, i.p.) significantly restored the hypotensive effect of bolus injection of GTN in rats made tolerants to organic nitrates via chronic administration of isosorbide-5-mononitrate (IS-5-MN), thus confirming the role of peroxynitrite overproduction in the development of tolerance to vascular responses induced by organic nitrates. In conclusion, oxidative stress subsequent to prolonged use of organic nitrates, which occurs via nitration of ALDH-2, represents a key event

  15. ROLE OF MANGANESE REDUCTION/OXIDATION (REDOX) ON FOAMING AND MELT RATE IN HIGH LEVEL WASTE (HLW) MELTERS (U)

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C; Michael Stone, M

    2007-03-30

    High-level nuclear waste is being immobilized at the Savannah River Site (SRS) by vitrification into borosilicate glass at the Defense Waste Processing Facility (DWPF). Control of the Reduction/Oxidation (REDOX) equilibrium in the DWPF melter is critical for processing high level liquid wastes. Foaming, cold cap roll-overs, and off-gas surges all have an impact on pouring and melt rate during processing of high-level waste (HLW) glass. All of these phenomena can impact waste throughput and attainment in Joule heated melters such as the DWPF. These phenomena are caused by gas-glass disequilibrium when components in the melter feeds convert to glass and liberate gases such as H{sub 2}O vapor (steam), CO{sub 2}, O{sub 2}, H{sub 2}, NO{sub x}, and/or N{sub 2}. During the feed-to-glass conversion in the DWPF melter, multiple types of reactions occur in the cold cap and in the melt pool that release gaseous products. The various gaseous products can cause foaming at the melt pool surface. Foaming should be avoided as much as possible because an insulative layer of foam on the melt surface retards heat transfer to the cold cap and results in low melt rates. Uncontrolled foaming can also result in a blockage of critical melter or melter off-gas components. Foaming can also increase the potential for melter pressure surges, which would then make it difficult to maintain a constant pressure differential between the DWPF melter and the pour spout. Pressure surges can cause erratic pour streams and possible pluggage of the bellows as well. For these reasons, the DWPF uses a REDOX strategy and controls the melt REDOX between 0.09 {le} Fe{sup 2+}/{summation}Fe {le} 0.33. Controlling the DWPF melter at an equilibrium of Fe{sup +2}/{summation}Fe {le} 0.33 prevents metallic and sulfide rich species from forming nodules that can accumulate on the floor of the melter. Control of foaming, due to deoxygenation of manganic species, is achieved by converting oxidized MnO{sub 2} or Mn

  16. Relationship of endothelial nitric oxide synthase gene polymorphism with blood pressure,lipid profile and blood glucose level

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To study the relationship of the polymorphism of endothelial nitric oxide synthase(eNOS)gene and blood pressure,lipid profiles and blood glucose level.By using PCR-RFLP,the eNOS Glu298Asp gene polymorphism was detected in 184 patients with essential hypertension and 196 matched healthy individuals with normal blood pressure.Taking into account eNOS Glu298Asp polymorphisms,the relationship of blood pressure with triglycerides(TG),total cholesterol(TC),high density lipoprotein(HDL),low density lipoprotein(LDL)and blood glucose level was analyzed.The distribution of eNOS Glu298Asp polymorphism had no significant difference between different blood pressure groups and gender groups,but there was a significant difference between different age groups,diastolic blood pressure groups or BMI groups(P<0.05).Asp/Asp genotype significantly increased the risk of hypertension in individuals with serum TC above 5.4 mmol/L(P=0.03,OR=2.65).eNOSGlu298Asp polymorphism and serum lipid could synergistically modulate the blood pressure,eNOS Asp/Asp genotype could significantly increase the risk of hypertension in individuals with serum TC over 5.4 mmol/L,eNOS Glu298Asp in combination with serum TC could be used to predict the risk of hypertension.

  17. Expression of FOXO6 is Associated With Oxidative Stress Level and Predicts the Prognosis in Hepatocellular Cancer

    Science.gov (United States)

    Chen, Hai-Yong; Chen, Yao-Min; Wu, Jian; Yang, Fu-Chun; Lv, Zhen; Xu, Xiao-Feng; Zheng, Shu-Sen

    2016-01-01

    Abstract The aim of this study was to explore the association of Forkhead box O6 (FOXO6) expression with oxidative stress level and prognosis of hepatocellular cancer (HCC). The case group included tissues of HCC from 128 patients who were hospitalized in Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery of First Affiliated Hospital, School of Medicine, Zhejiang University. The control group included normal liver tissues from 74 patients. RT-PCR and Western blot were used to test expressions of FOXO6, heme oxygenase (HO)-1, glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). Dihydroethidium (DHE) was dyed to observe reactive oxygen species (ROS) level. Immunohistochemistry was used to test FOXO6 expression. FOXO6 was silenced in HepG2 cells to detect cell proliferation and apoptosis. The expressions of ROS, HO-1, GPx, SOD, CAT, p27, and cyclin D1 were also detected to further explore the possible mechanism. The expressions of FOXO6, HO-1, GPx, SOD, and CAT in HCC tissue was significantly higher than those in normal and adjacent HCC tissues (P cancer, which may provide a novel treatment target for HCC therapy. PMID:27227932

  18. Characterization of aldehyde dehydrogenase isozymes in ovarian cancer tissues and sphere cultures

    International Nuclear Information System (INIS)

    Aldehyde dehydrogenases belong to a superfamily of detoxifying enzymes that protect cells from carcinogenic aldehydes. Of the superfamily, ALDH1A1 has gained most attention because current studies have shown that its expression is associated with human cancer stem cells. However, ALDH1A1 is only one of the 19 human ALDH subfamilies currently known. The purpose of the present study was to determine if the expression and activities of other major ALDH isozymes are associated with human ovarian cancer and ovarian cancer sphere cultures. Immunohistochemistry was used to delineate ALDH isozyme localization in clinical ovarian tissues. Western Blot analyses were performed on lysates prepared from cancer cell lines and ovarian cancer spheres to confirm the immunohistochemistry findings. Quantitative reverse transcription-polymerase chain reactions were used to measure the mRNA expression levels. The Aldefluor® assay was used to measure ALDH activity in cancer cells from the four tumor subtypes. Immunohistochemical staining showed significant overexpression of ALDH1A3, ALDH3A2, and ALDH7A1 isozymes in ovarian tumors relative to normal ovarian tissues. The expression and activity of ALDH1A1 is tumor type-dependent, as seen from immunohistochemisty, Western blot analysis, and the Aldefluor® assay. The expression was elevated in the mucinous and endometrioid ovarian epithelial tumors than in serous and clear cell tumors. In some serous and most clear cell tumors, ALDH1A1 expression was found in the stromal fibroblasts. RNA expression of all studied ALDH isozymes also showed higher expression in endometrioid and mucinous tumors than in the serous and clear cell subtypes. The expression of ALDH enzymes showed tumor type-dependent induction in ovarian cancer cells growing as sphere suspensions in serum-free medium. The results of our study indicate that ALDH enzyme expression and activity may be associated with specific cell types in ovarian tumor tissues and vary according to

  19. (−)-EPICATECHIN IMPROVES MITOCHONDRIAL RELATED PROTEIN LEVELS AND AMELIORATES OXIDATIVE STRESS IN DYSTROPHIC DELTA SARCOGLYCAN NULL MOUSE STRIATED MUSCLE

    Science.gov (United States)

    Ramirez-Sanchez, Israel; De los Santos, Sergio; Gonzalez-Basurto, Silvia; Canto, Patricia; Mendoza-Lorenzo, Patricia; Palma-Flores, Carlos; Ceballos-Reyes, Guillermo; Villarreal, Francisco; Zentella-Dehesa, Alejandro; Coral-Vazquez, Ramon

    2014-01-01

    Muscular dystrophies (MD) are a group of heterogeneous genetic disorders characterized by progressive striated muscle wasting and degeneration. Although the genetic basis for many of these disorders has been identified, the exact mechanism for disease pathogenesis remains unclear. The presence of oxidative stress (OS) is known to contribute to the pathophysiology and severity of the MD. Mitochondrial dysfunction is observed in MD and likely represents an important determinant of increased OS. Experimental antioxidant therapies have been implemented with the aim of protecting against disease progression, but results from clinical trials have been disappointing. In this study, we explored the capacity of the cacao flavonoid (−)-epicatechin (Epi) to mitigate OS by acting as a positive regulator of mitochondrial structure/function endpoints and redox balance control systems in skeletal and cardiac muscles of dystrophic, δ-sarcoglycan (δ-SG) null mice. Wild type or δ-SG null 2.5 month old male mice were treated via oral gavage with either water (control animals) or Epi (1 mg/kg, twice/day) for 2 weeks. Results evidence a significant normalization of total protein carbonylation, recovery of reduced/oxidized glutathione (GSH/GSSG ratio) and enhanced superoxide dismutase 2, catalase and citrate synthase activities with Epi treatment. These effects were accompanied by increases in protein levels for thiolredoxin, glutathione peroxidase, superoxide dismutase 2, catalase and mitochondrial endpoints. Furthermore, we evidence decreases in heart and skeletal muscle fibrosis, accompanied with an improvement in skeletal muscle function with treatment. These results warrant the further investigation of Epi as a potential therapeutic agent to mitigate MD associated muscle degeneration. PMID:25284161

  20. The level of nitric oxide regulates lipocalin-2 expression under inflammatory condition in RINm5F beta-cells.

    Science.gov (United States)

    Chang, Seo-Yoon; Kim, Dong-Bin; Ko, Seung-Hyun; Jang, Hyun-Jong; Jo, Yang-Hyeok; Kim, Myung-Jun

    2016-07-15

    We previously reported that proinflammatory cytokines (interleukin-1β and interferon-γ) induced the expression of lipocalin-2 (LCN-2) together with inducible nitric oxide synthase (iNOS) in RINm5F beta-cells. Therefore, we examined the effect of nitric oxide (NO) on LCN-2 expression in cytokines-treated RINm5F beta-cells. Additionally, we observed the effect of LCN-2 on cell viability. First, we found the existence of LCN-2 receptor and the internalization of exogenous recombinant LCN-2 peptide in RINm5F and INS-1 beta-cells. Next, the effects of NO on LCN-2 expression were evaluated. Aminoguanidine, an iNOS inhibitor and iNOS gene silencing significantly inhibited cytokines-induced LCN-2 expression while sodium nitroprusside (SNP), an NO donor potentiated it. Luciferase reporter assay showed that transcription factor NF-κB was not involved in LCN-2 expression. Both LCN-2 mRNA and protein stability assays were conducted. SNP did not affect LCN-2 mRNA stability, however, it significantly reduced LCN-2 protein degradation. The LCN-2 protein degradation was significantly attenuated by MG132, a proteasome inhibitor. Finally, the effect of LCN-2 on cell viability was evaluated. LCN-2 peptide treatment and LCN-2 overexpression significantly reduced cell viability. FACS analysis showed that LCN-2 induced the apoptosis of the cells. Collectively, NO level affects LCN-2 expression via regulation of LCN-2 protein stability under inflammatory condition and LCN-2 may reduce beta-cell viability by promoting apoptosis. PMID:27233602

  1. Lymphocyte oxidative stress/genotoxic effects are related to serum IgG and IgA levels in coke oven workers.

    Science.gov (United States)

    Gao, Meili; Li, Yongfei; Zheng, Aqun; Xue, Xiaochang; Chen, Lan; Kong, Yu

    2014-01-01

    We investigated oxidative stress/genotoxic effects levels, immunoglobulin levels, polycyclic aromatic hydrocarbons (PAHs) levels exposed in 126 coke oven workers and in 78 control subjects, and evaluated the association between oxidative stress/genotoxic effects levels and immunoglobulin levels. Significant differences were observed in biomarkers, including 1-hydroxypyrene levels, employment time, percentages of alcohol drinkers, MDA, 8-OHdG levels, CTL levels and CTM, MN, CA frequency, and IgG, IgA levels between the control and exposed groups. Slightly higher 1-OHP levels in smoking users were observed. For the dose-response relationship of IgG, IgA, IgM, and IgE by 1-OHP, each one percentage increase in urinary 1-OHP generates a 0.109%, 0.472%, 0.051%, and 0.067% decrease in control group and generates a 0.312%, 0.538%, 0.062%, and 0.071% decrease in exposed group, respectively. Except for age, alcohol and smoking status, IgM, and IgE, a significant correlation in urinary 1-OHP and other biomarkers in the total population was observed. Additionally, a significant negative correlation in genotoxic/oxidative damage biomarkers of MDA, 8-OH-dG, CTL levels, and immunoglobins of IgG and IgA levels, especially in coke oven workers, was found. These data suggest that oxidative stress/DNA damage induced by PAHs may play a role in toxic responses for PAHs in immunological functions. PMID:25136686

  2. Lymphocyte Oxidative Stress/Genotoxic Effects Are Related to Serum IgG and IgA Levels in Coke Oven Workers

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    Meili Gao

    2014-01-01

    Full Text Available We investigated oxidative stress/genotoxic effects levels, immunoglobulin levels, polycyclic aromatic hydrocarbons (PAHs levels exposed in 126 coke oven workers and in 78 control subjects, and evaluated the association between oxidative stress/genotoxic effects levels and immunoglobulin levels. Significant differences were observed in biomarkers, including 1-hydroxypyrene levels, employment time, percentages of alcohol drinkers, MDA, 8-OHdG levels, CTL levels and CTM, MN, CA frequency, and IgG, IgA levels between the control and exposed groups. Slightly higher 1-OHP levels in smoking users were observed. For the dose-response relationship of IgG, IgA, IgM, and IgE by 1-OHP, each one percentage increase in urinary 1-OHP generates a 0.109%, 0.472%, 0.051%, and 0.067% decrease in control group and generates a 0.312%, 0.538%, 0.062%, and 0.071% decrease in exposed group, respectively. Except for age, alcohol and smoking status, IgM, and IgE, a significant correlation in urinary 1-OHP and other biomarkers in the total population was observed. Additionally, a significant negative correlation in genotoxic/oxidative damage biomarkers of MDA, 8-OH-dG, CTL levels, and immunoglobins of IgG and IgA levels, especially in coke oven workers, was found. These data suggest that oxidative stress/DNA damage induced by PAHs may play a role in toxic responses for PAHs in immunological functions.

  3. Potent inhibition of aldehyde dehydrogenase-2 by diphenyleneiodonium: focus on nitroglycerin bioactivation.

    Science.gov (United States)

    Neubauer, Regina; Neubauer, Andrea; Wölkart, Gerald; Schwarzenegger, Christine; Lang, Barbara; Schmidt, Kurt; Russwurm, Michael; Koesling, Doris; Gorren, Antonius C F; Schrammel, Astrid; Mayer, Bernd

    2013-09-01

    Aldehyde dehydrogenase-2 (ALDH2) catalyzes vascular bioactivation of the antianginal drug nitroglycerin (GTN) to yield nitric oxide (NO) or a related species that activates soluble guanylate cyclase (sGC), resulting in cGMP-mediated vasodilation. Accordingly, established ALDH2 inhibitors attenuate GTN-induced vasorelaxation in vitro and in vivo. However, the ALDH2 hypothesis has not been reconciled with early studies demonstrating potent inhibition of the GTN response by diphenyleneiodonium (DPI), a widely used inhibitor of flavoproteins, in particular NADPH oxidases. We addressed this issue and investigated the effects of DPI on GTN-induced relaxation of rat aortic rings and the function of purified ALDH2. DPI (0.3 µM) inhibited the high affinity component of aortic relaxation to GTN without affecting the response to NO, indicating that the drug interfered with GTN bioactivation. Denitration and bioactivation of 1-2 µM GTN, assayed as 1,2-glycerol dinitrate formation and activation of purified sGC, respectively, were inhibited by DPI with a half-maximally active concentration of about 0.2 µM in a GTN-competitive manner. Molecular modeling indicated that DPI binds to the catalytic site of ALDH2, and this was confirmed by experiments showing substrate-competitive inhibition of the dehydrogenase and esterase activities of the enzyme. Our data identify ALDH2 as highly sensitive target of DPI and explain inhibition of GTN-induced relaxation by this drug observed previously. In addition, the data provide new evidence for the essential role of ALDH2 in GTN bioactivation and may have implications to other fields of ALDH2 research, such as hepatic ethanol metabolism and cardiac ischemia/reperfusion injury.

  4. Research on Odor Interaction between Aldehyde Compounds via a Partial Differential Equation (PDE Model

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    LuchunYan

    2015-01-01

    Full Text Available In order to explore the odor interaction of binary odor mixtures, a series of odor intensity evaluation tests were performed using both individual components and binary mixtures of aldehydes. Based on the linear relation between the logarithm of odor activity value and odor intensity of individual substances, the relationship between concentrations of individual constituents and their joint odor intensity was investigated by employing a partial differential equation (PDE model. The obtained results showed that the binary odor interaction was mainly influenced by the mixing ratio of two constituents, but not the concentration level of an odor sample. Besides, an extended PDE model was also proposed on the basis of the above experiments. Through a series of odor intensity matching tests for several different binary odor mixtures, the extended PDE model was proved effective at odor intensity prediction. Furthermore, odorants of the same chemical group and similar odor type exhibited similar characteristics in the binary odor interaction. The overall results suggested that the PDE model is a more interpretable way of demonstrating the odor interactions of binary odor mixtures.

  5. Content of the Nitrogen Oxide Metabolites in a Condensate of Exhaling Air in Children with a Bronchial Asthma Control Different Level

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    Eliseeva T.I.

    2010-12-01

    Full Text Available Aim of investigation is establishment of regularity of the nitrogen oxide metabolite content change in the exhaling air condensate (EAC in children with a bronchial asthma control different level, assessed with a use of the ACQ day and week scales (Asthma Control Questionnaire. Materials and Methods. A summarized content of nitrites and nitrates in the exhaling air condensate in 61 infants with a bronchial asthma control different level is analyzed; it is analyzed in a disease dynamics in a part of them. Results. A summarized content of the nitrogen oxide metabolites in the EAC in patients with an absolute and full control of a bronchial asthma, not receiving the glucocorticosteroid therapy, was trustworthy higher than in patients, receiving that therapy. A trustworthy dependence between a summarized content of the nitrogen oxide metabolites in the EAC and a level of a bronchial asthma control in patients, receiving a similar therapy (with the glucocorticosteroid inclusion, is established.

  6. Synthesis and accumulation of aromatic aldehydes in an engineered strain of Escherichia coli.

    Science.gov (United States)

    Kunjapur, Aditya M; Tarasova, Yekaterina; Prather, Kristala L J

    2014-08-20

    Aromatic aldehydes are useful in numerous applications, especially as flavors, fragrances, and pharmaceutical precursors. However, microbial synthesis of aldehydes is hindered by rapid, endogenous, and redundant conversion of aldehydes to their corresponding alcohols. We report the construction of an Escherichia coli K-12 MG1655 strain with reduced aromatic aldehyde reduction (RARE) that serves as a platform for aromatic aldehyde biosynthesis. Six genes with reported activity on the model substrate benzaldehyde were rationally targeted for deletion: three genes that encode aldo-keto reductases and three genes that encode alcohol dehydrogenases. Upon expression of a recombinant carboxylic acid reductase in the RARE strain and addition of benzoate during growth, benzaldehyde remained in the culture after 24 h, with less than 12% conversion of benzaldehyde to benzyl alcohol. Although individual overexpression results demonstrated that all six genes could contribute to benzaldehyde reduction in vivo, additional experiments featuring subset deletion strains revealed that two of the gene deletions were dispensable under the conditions tested. The engineered strain was next investigated for the production of vanillin from vanillate and succeeded in preventing formation of the byproduct vanillyl alcohol. A pathway for the biosynthesis of vanillin directly from glucose was introduced and resulted in a 55-fold improvement in vanillin titer when using the RARE strain versus the wild-type strain. Finally, synthesis of the chiral pharmaceutical intermediate L-phenylacetylcarbinol (L-PAC) was demonstrated from benzaldehyde and glucose upon expression of a recombinant mutant pyruvate decarboxylase in the RARE strain. Beyond allowing accumulation of aromatic aldehydes as end products in E. coli, the RARE strain expands the classes of chemicals that can be produced microbially via aldehyde intermediates. PMID:25076127

  7. Microenvironmental characteristics important for personal exposures to aldehydes in Sacramento, CA, and Milwaukee, WI

    Science.gov (United States)

    Raymer, J. H.; Akland, G.; Johnson, T. R.; Long, T.; Michael, L.; Cauble, L.; McCombs, M.

    Oxygenated additives in gasoline are designed to decrease the ozone-forming hydrocarbons and total air toxics, yet they can increase the emissions of aldehydes and thus increase human exposure to these toxic compounds. This paper describes a study conducted to characterize targeted aldehydes in microenvironments in Sacramento, CA, and Milwaukee, WI, and to improve our understanding of the impact of the urban environment on human exposure to air toxics. Data were obtained from microenvironmental concentration measurements, integrated, 24-h personal measurements, indoor and outdoor pollutant monitors at the participants' residences, from ambient pollutant monitors at fixed-site locations in each city, and from real-time diaries and questionnaires completed by the technicians and participants. As part of this study, a model to predict personal exposures based on individual time/activity data was developed for comparison to measured concentrations. Predicted concentrations were generally within 25% of the measured concentrations. The microenvironments that people encounter daily provide for widely varying exposures to aldehydes. The activities that occur in those microenvironments can modulate the aldehyde concentrations dramatically, especially for environments such as "indoor at home." By considering personal activity, location (microenvironment), duration in the microenvironment, and a knowledge of the general concentrations of aldehydes in the various microenvironments, a simple model can do a reasonably good job of predicting the time-averaged personal exposures to aldehydes, even in the absence of monitoring data. Although concentrations of aldehydes measured indoors at the participants' homes tracked well with personal exposure, there were instances where personal exposures and indoor concentrations differed significantly. Key to the ability to predict exposure based on time/activity data is the quality and completeness of the microenvironmental

  8. Identification and characterization of an antennae-specific aldehyde oxidase from the navel orangeworm.

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    Young-Moo Choo

    Full Text Available Antennae-specific odorant-degrading enzymes (ODEs are postulated to inactivate odorant molecules after they convey their signal. Different classes of insect ODEs are specific to esters, alcohols, and aldehydes--the major functional groups of female-produced, hydrophobic sex pheromones from moth species. Esterases that rapidly inactive acetate and other esters have been well-studied, but less is known about aldehyde oxidases (AOXs. Here we report cloning of an aldehyde oxidase, AtraAOX2, from the antennae of the navel orangeworm (NOW, Amyelois transitella, and the first activity characterization of a recombinant insect AOX. AtraAOX2 gene spans 3,813 bp and encodes a protein with 1,270 amino acid residues. AtraAOX2 cDNA was expressed in baculovirus-infected insect Sf21 cells as a ≈280 kDa homodimer with 140 kDa subunits. Recombinant AtraAOX2 degraded Z11Z13-16Ald and plant volatile aldehydes as substrates. However, as expected for aldehyde oxidases, recombinant AtraAOX2 did not show specificity for Z11Z13-16Ald, the main constituent of the sex pheromone, but showed high activity for plant volatile aldehydes. Our data suggest AtraAOX2 might be involved in degradation of a diversity of aldehydes including sex pheromones, plant-derived semiochemicals, and chemical cues for oviposition sites. Additionally, AtraAOX2 could protect the insect's olfactory system from xenobiotics, including pesticides that might reach the sensillar lymph surrounding the olfactory receptor neurons.

  9. IPOMOEA BATATAS SYRUP DECREASE MALONDIALDEHYDE AND INCREASE NITROUS OXIDE PLASMA LEVELS AMONGST MODERATE SMOKER WORKERS AT DENPASAR

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    I Dewa Ayu Intan Dwi-Primayanti

    2012-09-01

    Full Text Available Objective: Cells and tissues are continuously damaged by reactive oxygen species. Cigarette smoke is one of an exogenous source of free radical containing more than 4000 chemical compounds, that triggering the formation of free radicals related to diseases and aging process. Anthocyanins are potent antioxidants that are widely distributed in fruit, vegetables, red wines and Ipomea batatas. The aim of this study was to determine the effect of Ipomea batatas as a source of antioxidants in decreasing levels of alondialdehyde (MDA and increasing of Nitrous oxide (nitrite/nitrate/NOxplasma in moderate smokers of workers at Denpasar.Method: This was an experimental study with a pretest-posttest control groups design. There are 33 moderate smokers who were divided into three groups, control group (placebo, treatment group with 15 ml purple sweet potato syrup (P1 and 30 ml (P2, for 14 days. All groups were performed the laboratory examinations for MDA and NOx plasma before and after the treatment.Results: This study showed that there were significant differences (p<0.05 both in MDA and NOx plasma levels in the control group, P1 and P2. The decrease of MDAlevels on P1 was 35.39% and on P2 was 49.87%. The increase of NOx plasma levels was 7.78% for P1 and 14.68% for P2.Conclusion: From this study, it can be concluded that Ipomea batatas syrup contains of 8mg/mL anthocyanins, probably play a role in reducing the free radical and thus reducingthe risk of disease and slowing the aging process.

  10. Genome-wide identification and analysis of the aldehyde dehydrogenase (ALDH) gene superfamily in apple (Malus × domestica Borkh.).

    Science.gov (United States)

    Li, Xiaoqin; Guo, Rongrong; Li, Jun; Singer, Stacy D; Zhang, Yucheng; Yin, Xiangjing; Zheng, Yi; Fan, Chonghui; Wang, Xiping

    2013-10-01

    Aldehyde dehydrogenases (ALDHs) represent a protein superfamily encoding NAD(P)(+)-dependent enzymes that oxidize a wide range of endogenous and exogenous aliphatic and aromatic aldehydes. In plants, they are involved in many biological processes and play a role in the response to environmental stress. In this study, a total of 39 ALDH genes from ten families were identified in the apple (Malus × domestica Borkh.) genome. Synteny analysis of the apple ALDH (MdALDH) genes indicated that segmental and tandem duplications, as well as whole genome duplications, have likely contributed to the expansion and evolution of these gene families in apple. Moreover, synteny analysis between apple and Arabidopsis demonstrated that several MdALDH genes were found in the corresponding syntenic blocks of Arabidopsis, suggesting that these genes appeared before the divergence of lineages that led to apple and Arabidopsis. In addition, phylogenetic analysis, as well as comparisons of exon-intron and protein structures, provided further insight into both their evolutionary relationships and their putative functions. Tissue-specific expression analysis of the MdALDH genes demonstrated diverse spatiotemporal expression patterns, while their expression profiles under abiotic stress and various hormone treatments indicated that many MdALDH genes were responsive to high salinity and drought, as well as different plant hormones. This genome-wide identification, as well as characterization of evolutionary relationships and expression profiles, of the apple MdALDH genes will not only be useful for the further analysis of ALDH genes and their roles in stress response, but may also aid in the future improvement of apple stress tolerance.

  11. Characterization of airway inflammation in patients with COPD using fractional exhaled nitric oxide levels: a pilot study

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    Donohue JF

    2014-07-01

    Full Text Available James F Donohue,1 Nancy Herje,2 Glenn Crater,2 Kathleen Rickard2 1Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, NC, USA; 2Aerocrine, Inc., Morrisville, NC, USA Objective: To characterize fractional exhaled nitric oxide (FeNO levels that may be indicative of Th2-mediated airway inflammation in patients with chronic obstructive pulmonary disease (COPD. Methods: This single-visit, outpatient study was conducted in 200 patients aged 40 years and older with COPD. All patients underwent spirometry and FeNO testing. COPD severity was classified according to the Global initiative for chronic Obstructive Lung Disease (GOLD 2010 guidelines. Results: Patients who participated in the study had a mean age of 63.9±11.3 years and a mean smoking history of 46±29 pack years. Patients had a mean forced expiratory volume in 1 second % predicted of 53.9%±22.1%. The percentage of patients classified with COPD severity Stage I, II, III, and IV was 13%, 40%, 39%, and 8%, respectively. In addition, according to current procedural terminology codes, 32% of patients were classified as mixed COPD/asthma, 26% as COPD/emphysema, and 42% as all other codes. The mean FeNO level for all patients was 15.3±17.2 parts per billion (ppb. Overall, 89% of patients had a FeNO <25 ppb, 8% had a FeNO 25–50 ppb, and 3% had a FeNO >50 ppb. The percentages of patients with FeNO in the intermediate or high ranges of FeNO were greatest among patients with mixed COPD/asthma (intermediate, 11.5%; high, 6.6% compared with COPD/emphysema (intermediate, 8%; high, 0 and all other codes (intermediate, 6.3%; high, 1.3%. Conclusion: Increases in FeNO were identified in a subset of patients with COPD, particularly in those previously diagnosed with both COPD and asthma. Since FeNO is useful for identifying patients with airway inflammation who will have a beneficial response to treatment with an inhaled corticosteroid, these data may have important

  12. Development of a novel graphene/polyaniline electrodeposited coating for on-line in-tube solid phase microextraction of aldehydes in human exhaled breath condensate.

    Science.gov (United States)

    Li, Yu; Xu, Hui

    2015-05-22

    In this work, we introduced a novel graphene/polyaniline (G/PANI) electrodeposited coating for on-line in-tube solid phase microextraction (IT-SPME) for the first time. The G/PANI coating was prepared on the internal surface of stainless steel tube by a facile in-situ electrodeposition method. The morphology and formation of the composite coating were confirmed by scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Some important experimental parameters that could affect the extraction and separation such as the coating thickness, internal diameter of tube, sampling flow rate as well as sample volume were optimized. The extraction performance of the IT-SPME coating was evaluated systematically. The coating exhibited enhanced mechanical stability, long lifespan, large specific surface area and good biocompatibility compared with polyaniline coating. The on-line IT-SPME method showed higher enrichment efficiency, faster analysis speed and higher automation level than off-line manual mode. Six aldehydes were determined simultaneously with low limits of detection of 0.02-0.04nmolL(-1) and good linearity (R(2)≥0.9920). The method has been applied successfully for the determination of aldehydes in human exhaled breath condensates with good recovery (70-120%) and satisfied reproducibility (relative standard deviation: 1.1-11.9%). This on-line IT-SPME method provides a promising approach for the determination of trace aldehydes with approving sensitivity in human exhaled breath condensates. PMID:25863926

  13. Isobutyraldehyde production from Escherichia coli by removing aldehyde reductase activity

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    Rodriguez Gabriel M

    2012-06-01

    Full Text Available Abstract Background Increasing global demand and reliance on petroleum-derived chemicals will necessitate alternative sources for chemical feedstocks. Currently, 99% of chemical feedstocks are derived from petroleum and natural gas. Renewable methods for producing important chemical feedstocks largely remain unaddressed. Synthetic biology enables the renewable production of various chemicals from microorganisms by constructing unique metabolic pathways. Here, we engineer Escherichia coli for the production of isobutyraldehyde, which can be readily converted to various hydrocarbons currently derived from petroleum such as isobutyric acid, acetal, oxime and imine using existing chemical catalysis. Isobutyraldehyde can be readily stripped from cultures during production, which reduces toxic effects of isobutyraldehyde. Results We adopted the isobutanol pathway previously constructed in E. coli, neglecting the last step in the pathway where isobutyraldehyde is converted to isobutanol. However, this strain still overwhelmingly produced isobutanol (1.5 g/L/OD600 (isobutanol vs 0.14 g/L/OD600 (isobutyraldehyde. Next, we deleted yqhD which encodes a broad-substrate range aldehyde reductase known to be active toward isobutyraldehyde. This strain produced isobutanol and isobutyraldehyde at a near 1:1 ratio, indicating further native isobutyraldehyde reductase (IBR activity in E. coli. To further eliminate isobutanol formation, we set out to identify and remove the remaining IBRs from the E. coli genome. We identified 7 annotated genes coding for IBRs that could be active toward isobutyraldehyde: adhP, eutG, yiaY, yjgB, betA, fucO, eutE. Individual deletions of the genes yielded only marginal improvements. Therefore, we sequentially deleted all seven of the genes and assessed production. The combined deletions greatly increased isobutyraldehyde production (1.5 g/L/OD600 and decreased isobutanol production (0.4 g/L/OD600. By assessing production by

  14. Quantification of aldehydes emissions from alternative and renewable aviation fuels using a gas turbine engine

    Science.gov (United States)

    Li, Hu; Altaher, Mohamed A.; Wilson, Chris W.; Blakey, Simon; Chung, Winson; Rye, Lucas

    2014-02-01

    In this research three renewable aviation fuel blends including two HEFA (Hydrotreated Ester and Fatty Acid) blends and one FAE (Fatty Acids Ethyl Ester) blend with conventional Jet A-1 along with a GTL (Gas To Liquid) fuel have been tested for their aldehydes emissions on a small gas turbine engine. Three strong ozone formation precursors: formaldehyde, acetaldehyde and acrolein were measured in the exhaust at different operational modes and compared to neat Jet A-1. The aim is to assess the impact of renewable and alternative aviation fuels on aldehydes emissions from aircraft gas turbine engines so as to provide informed knowledge for the future deployment of new fuels in aviation. The results show that formaldehyde was a major aldehyde species emitted with a fraction of around 60% of total measured aldehydes emissions for all fuels. Acrolein was the second major emitted aldehyde species with a fraction of ˜30%. Acetaldehyde emissions were very low for all the fuels and below the detention limit of the instrument. The formaldehyde emissions at cold idle were up to two to threefold higher than that at full power. The fractions of formaldehyde were 6-10% and 20% of total hydrocarbon emissions in ppm at idle and full power respectively and doubled on a g kg-1-fuel basis.

  15. Toxicity of polyunsaturated aldehydes of diatoms to Indo-Pacific bioindicator organism Echinometra mathaei.

    Science.gov (United States)

    Sartori, Davide; Gaion, Andrea

    2016-01-01

    Although it is well known suitability of early developmental stages of sea urchin as recommended model for pollutant toxicity testing, little is known about the sensitivity of Indo-Pacific species Echinometra mathaei to polyunsaturated aldehydes. In this study, the effect of three short chain aldehydes, 2,4-decadienal (DD), 2,4-octadienal (OD) and 2,4-heptadienal (HD), normally found in many diatoms, such as Skeletonema costatum, Skeletonema marinoi and Thalassiosira rotula, was evaluated on larval development of E. mathaei embryos. Aldehydes affected larval development in a dose-dependent manner, in particular HD>OD>DD; the results of this study highlighted the higher sensitivity of this species toward aldehydes compared with data registered for other sea urchin species. In comparison with studies reported in the literature, contrasting results were observed during our tests; therefore, an increasing toxic effect was registered with decreasing the chain length of aldehydes. This work could provide new insights in the development of new toxicological assays toward most sensitive species. PMID:25945412

  16. Energy level alignment of electrically doped hole transport layers with transparent and conductive indium tin oxide and polymer anodes

    Science.gov (United States)

    Fehse, Karsten; Olthof, Selina; Walzer, Karsten; Leo, Karl; Johnson, Robert L.; Glowatzki, Hendrik; Bröker, Benjamin; Koch, Norbert

    2007-10-01

    Using ultraviolet photoemission spectroscopy, we investigated the energy level alignment at the interfaces of typical anodes used in organic electronics, indium tin oxide (ITO) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), with the oligomeric hole transport material N ,N,N',N'-tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD), and studied the influence of electrical interface doping by the strong electron acceptor tetrafluoro tetracyanoquinodimethane (F4-TCNQ). The fundamentally different anode materials with work functions of 4.40eV (ITO) and 4.85eV (PEDOT:PSS) show different hole injection barriers, which also depend on the thickness of the F4-TCNQ interface dopant layer. PEDOT:PSS anodes exhibit a consistently lower hole injection barrier to MeO-TPD compared to ITO by 0.1eV. We attribute this low hole injection barrier to additional charge transfer reactions at the PEDOT:PSS/MeO-TPD interface. In contrast, the deposition of the electron acceptor at the interface helps significantly to lower the hole injection barrier for ITO anodes.

  17. Mechanical and electrical properties of carbon nanotube/Cu nanocomposites by molecular-level mixing and controlled oxidation process.

    Science.gov (United States)

    Lim, Byung K; Mo, Chan B; Nam, Dong H; Hong, Soon H

    2010-01-01

    A molecular-level mixing and controlled oxidation process is proposed as a novel fabrication technique for the production of CNT/Cu nanocomposite powders. The fabricated CNT/Cu2O nanocomposite powders showed microstructures with homogeneous dispersion of implanted CNTs in a Cu2O matrix. The CNT/Cu2O nanocomposite powders were reduced to CNT/Cu nanocomposite powders with H2 gas and then the as-prepared CNT/Cu nanocomposite powders were spark plasma sintered to fabricate CNT/Cu nanocomposites. The mechanical properties of the Cu and the CNT/Cu nanocomposites were characterized by tensile testing before and after hot compression. Before hot compression, the CNT/Cu nanocomposites were brittle, but after hot compression both yield strength and elongation were increased, while the yield strength of the Cu was decreased after hot compression. Hot compression enhanced the ductility and strength of the CNT/Cu nanocomposites due to alignment of Cu grains and CNTs. Electrical conductivity was also enhanced due to a reduced scattering of electrons because of the alignment of the CNTs and Cu grains as well as the annealing effects of the Cu matrix. PMID:20352814

  18. The role of surface and deep-level defects on the emission of tin oxide quantum dots

    International Nuclear Information System (INIS)

    This paper reports on the role of surface and deep-level defects on the blue emission of tin oxide quantum dots (SnO2 QDs) synthesized by the solution-combustion method at different combustion temperatures. X-ray diffraction studies showed the formation of a single rutile SnO2 phase with a tetragonal lattice structure. High resolution transmission electron microscopy studies revealed an increase in the average dot size from 2.2 to 3.6 nm with an increase of the combustion temperature from 350 to 550 °C. A decrease in the band gap value from 3.37 to 2.76 eV was observed with the increase in dot size due to the quantum confinement effect. The photoluminescence emission was measured for excitation at 325 nm and it showed a broad blue emission band for all the combustion temperatures studied. This was due to the creation of various oxygen and tin vacancies/defects as confirmed by x-ray photoelectron spectroscopy data. The origin of the blue emission in the SnO2 QDs is discussed with the help of an energy band diagram. (paper)

  19. Device level optimization of poly(vinylidene fluoride-trifluoroethylene)–zinc oxide polymer nanocomposite thin films for ferroelectric applications

    International Nuclear Information System (INIS)

    Polymer nanocomposite was prepared using poly(vinylidene fluoride-trifluoroethylene) and zinc oxide (ZnO) nanopowder, which are ferroelectric in nature. Nanocomposite was prepared in various concentrations(0.2, 0.4, 0.8, and 1 wt. %) using probe ultra-sonication, followed by spin coating and annealing at 120 °C for 2 h to improve the formation of β-phase. Metal-ferroelectric-metal capacitor was fabricated using this optimized thin film as a ferroelectric layer. Device level optimization was carried out by polarization-electric field (P-E) hysteresis studies of this film, which shows polarization enhancement of composite. Various characterization techniques like atomic force microscopy, Fourier transform infra-red spectroscopy (FT-IR), Differential scanning calorimetry, and X-ray diffraction were used to study the β-phase formation of nancomposite. The capacitance–voltage (C-V) and current-voltage (I-V) characteristics were studied through varying frequency and temperature. C-V measurements show an increase of 79% in the capacitance of polymer nanocomposite, which can be used for the fabrication of ferroelectric devices

  20. Device level optimization of poly(vinylidene fluoride-trifluoroethylene)-zinc oxide polymer nanocomposite thin films for ferroelectric applications

    Science.gov (United States)

    C K, Subash; Valiyaneerilakkal, Uvais; Singh, Kulwant; Varghese, Soney

    2015-11-01

    Polymer nanocomposite was prepared using poly(vinylidene fluoride-trifluoroethylene) and zinc oxide (ZnO) nanopowder, which are ferroelectric in nature. Nanocomposite was prepared in various concentrations(0.2, 0.4, 0.8, and 1 wt. %) using probe ultra-sonication, followed by spin coating and annealing at 120 °C for 2 h to improve the formation of β-phase. Metal-ferroelectric-metal capacitor was fabricated using this optimized thin film as a ferroelectric layer. Device level optimization was carried out by polarization-electric field (P-E) hysteresis studies of this film, which shows polarization enhancement of composite. Various characterization techniques like atomic force microscopy, Fourier transform infra-red spectroscopy (FT-IR), Differential scanning calorimetry, and X-ray diffraction were used to study the β-phase formation of nancomposite. The capacitance-voltage (C-V) and current-voltage (I-V) characteristics were studied through varying frequency and temperature. C-V measurements show an increase of 79% in the capacitance of polymer nanocomposite, which can be used for the fabrication of ferroelectric devices.